U.S. patent application number 13/265206 was filed with the patent office on 2012-02-16 for two-part endoscope surgical device.
This patent application is currently assigned to M.S.T. MEDICAL SURGERY TECHNOLOGIES LTD.. Invention is credited to Mordehai Sholev.
Application Number | 20120041263 13/265206 |
Document ID | / |
Family ID | 43010736 |
Filed Date | 2012-02-16 |
United States Patent
Application |
20120041263 |
Kind Code |
A1 |
Sholev; Mordehai |
February 16, 2012 |
TWO-PART ENDOSCOPE SURGICAL DEVICE
Abstract
The present invention provides a two-part robotic device for
positioning of a hand tool, comprising: a. a fixed base unit
constantly fix to its position; b. a detachable body unit
reversibly coupled to said fixed base unit, coupled to said current
medical instrument; wherein said fixed base unit is adapted to
provide independent movement to said hand tool, said independent
movement selected from the group consisting of rotation and
translation, and further wherein said detachable body unit is
removable and replaceable from said fixed base unit such that upon
exchange of said hand tool for a second hand tool, said second hand
tool is placed in substantially the same location as the location
of said hand tool prior to said exchange.
Inventors: |
Sholev; Mordehai; (Amikam,
IL) |
Assignee: |
M.S.T. MEDICAL SURGERY TECHNOLOGIES
LTD.
Yoqneam
IL
|
Family ID: |
43010736 |
Appl. No.: |
13/265206 |
Filed: |
April 22, 2010 |
PCT Filed: |
April 22, 2010 |
PCT NO: |
PCT/IL10/00330 |
371 Date: |
October 19, 2011 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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61171848 |
Apr 23, 2009 |
|
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61324324 |
Apr 15, 2010 |
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Current U.S.
Class: |
600/118 |
Current CPC
Class: |
A61B 34/30 20160201;
A61B 2034/2051 20160201; A61B 1/00128 20130101; A61B 90/50
20160201; A61B 90/98 20160201; A61B 1/00149 20130101; A61B 1/313
20130101; A61B 2090/508 20160201 |
Class at
Publication: |
600/118 |
International
Class: |
A61B 1/00 20060101
A61B001/00 |
Claims
1-42. (canceled)
43. A two-part robotic device for positioning of a hand tool,
comprising: a. a fixed base unit constantly fix to its position; b.
a detachable body unit reversibly coupled to said fixed base unit,
coupled to said current medical instrument; wherein said fixed base
unit is adapted to provide independent movement to said hand tool,
said independent movement selected from the group consisting of
rotation and translation, and further wherein said detachable body
unit is removable and replaceable from said fixed base unit such
that upon exchange of said hand tool for a second hand tool, said
second hand tool is placed in substantially the same location as
the location of said hand tool prior to said exchange.
44. The two-part robotic device according to claim 43, wherein said
hand tool is a medical instrument.
45. The two-part robotic device according to claim 44, wherein said
medical instrument is selected from the group consisting of
endoscope, laparoscope, forceps, and any combination thereof.
46. The two-part robotic device according to claim 44, wherein said
detachable body unit is an endoscope positioning device comprising
means for providing to said endoscope at least 7 degrees of freedom
(DOF) selected from the group consisting of at least 6 rotation
movements (1007, 1009, 1010, 1011, 1012, 1013, 1601, 1602), at
least 1 translation movement (1008) and any combination
thereof.
47. The two-part robotic device according to claim 43, wherein said
detachable body unit comprises: a. k consecutive arm sections, each
comprising n coaxial input shafts adapted to be rotated around an
input axis of rotation by m sources of torque, wherein n, m, and k
are positive integers, and further wherein said hand tool is
coupled to one of said k consecutive arm sections; and, b. at least
k-1 constant velocity couplers coupling each pair of said k
consecutive arm sections together, each of said constant velocity
couplers comprising: i. n coaxial input transmission means, each of
which is coupled to one of said n input shafts, said input
transmission means defining a first plane substantially
perpendicular to said input axis of rotation; ii. n coaxial second
transmission means rotatably connected to said n input transmission
means, said second transmission means rotating in a second plane,
said second plane substantially perpendicular to said first plane;
iii. n coaxial output transmission means rotatably connected to
said n second transmission means, said output transmission means
rotating in a third plane; said third plane being substantially
perpendicular to said second plane; and, iv. n coaxial output
shafts, each of which is coupled to one of said n output
transmission means, said n output shafts being adapted to rotate
around an output axis of rotation such that (i) turning a given
input shaft at a constant velocity will provide a constant velocity
at the corresponding output shaft; and (ii) the angle between said
input axis of rotation and said output axis of rotation varies in
said second plane in an angular range of about 0 to about 360
degrees.
48. The two-part robotic device according to claim 43, wherein said
fixed base unit comprises: a. k consecutive arm sections, each
comprising n coaxial input shafts adapted to be rotated around an
input axis of rotation by m sources of torque, where n, m, and k
are positive integers, wherein said current instrument is coupled
to one of said k consecutive arm sections; b. at least k-1 constant
velocity couplers coupling each two of said k consecutive arm
sections together, each of said constant velocity couplers
comprising: i. n coaxial input transmission means, each of which is
coupled to one of said n input shafts, wherein said input
transmission means define a first plane substantially perpendicular
to said input axis of rotation; ii. n coaxial second transmission
means rotatably connected to said n input transmission means, said
second transmission means rotating in a second plane substantially
perpendicular to said first plane; iii. n coaxial output
transmission means rotatably connected to said n second
transmission means, said output transmission means rotating in a
third plane substantially perpendicular to said second plane; c. n
coaxial output shafts, each of which is coupled to one of said n
output transmission means, said n output shafts adapted to rotate
around an output axis of rotation; such that (i) turning a given
input shaft at a constant velocity will provide a constant velocity
at the corresponding output shaft and (ii) the angle between said
input axis of rotation and said output axis of rotation varies in
said second plane in an angular range of about 0 to about 360
degrees.
49. The two-part robotic device according to claim 43, wherein said
input transmission means, second transmission means, and said
output transmission means are selected from the group consisting of
gearwheels, wheels, crown gears, bevel gears, spur gears, belts,
and any combination thereof.
50. The two-part robotic device according to claim 43, additionally
comprising a. an axial support member (601) adapted to provide
axial support to said n output shafts in said third plane; and, b.
a circular track (618) centered on the axis of rotation of said
second transmission means, said axial support member being adapted
to fit into said track and slide within it.
51. The two-part robotic device according to claim 43, additionally
comprising a radial support member (604) adapted to provide radial
support to said n output shafts, said radial support member being
adapted to rotate in said second plane.
52. The two-part robotic device according to claim 43, wherein the
gear ratio between said input and output shafts is between about 10
and about 0.1.
53. The two-part robotic device according to claim 43, additionally
comprising n coaxial auxiliary shafts in rotating communication
with said n second transmission means, said n coaxial auxiliary
shafts rotating in said second plane, and said n coaxial auxiliary
shafts capable of either being driven by said input shafts or
driving said input shafts.
54. The two-part robotic device according to claim 43, additionally
comprising locking means adapted for preventing relative movement
between one or more of said input axis shafts and said constant
velocity joint, wherein said constant velocity joint is caused to
rotate as a body with said locked input axis shafts.
55. The two-part robotic device according to claim 43, additionally
comprising locking means for preventing relative movement between
one or more of said output axis shafts and said constant velocity
joint, wherein said constant velocity joint is caused to rotate as
a body with said locked output axis shafts.
56. The two-part robotic device according to claim 44, wherein said
device is adapted for use in sinus surgery.
57. The two-part robotic device according to claim 56, wherein said
sinus surgery is FESS.
58. A method for changing a medical instrument in use during
performance of laparoscopic surgery, said method comprising steps
of: a. providing a two-part robotic device comprising: i. a fixed
base unit, constantly fix to its position; and, ii. a detachable
body unit reversibly coupled to said fixed base unit, comprising
said medical instrument; b. coupling said detachable body unit to
said fixed base; c. providing independent movements to said current
medical instrument selected from the group consisting of rotation
and translation; thereby performing said laparoscopic surgery; d.
detaching said detachable body unit from said fixed base unit; and,
e. replacing said medical instrument in said detachable body unit
thereby changing said current medical instrument.
59. The method according to claim 58, additionally comprising step
of altering the modality of a laparoscopic surgery.
60. The method according to claim 59, wherein said step of
replacing additionally comprises steps of: a. providing a two-part
robotic device comprising: i. a fixed base unit, constantly fix to
its position; ii. a first detachable body unit reversibly coupled
to said fixed base unit, comprising said current medical
instrument; said first detachable body unit is adapted for
laparoscopic surgery of a first modality; b. coupling said first
detachable body unit to said fixed base; c. providing independent
movements to said current medical instrument selected from a group
consisting of rotation and translation; thereby performing said
laparoscopic surgery of said first modality with said first
detachable body unit; d. providing a second detachable body unit
adapted for laparoscopic surgery of a second modality; e.
decoupling said first detachable body unit from said fixed base; f.
coupling said second detachable body unit for laparoscopic surgery
of a second modality; g. performing laparoscopic surgery of said
second modality with said second detachable body unit; thereby
altering the modality of said laparoscopic surgery.
61. The two-part robotic device according to claim 44, additionally
comprising an interface between a surgeon and an automated
assistant, said interface comprising: a. at least one array
comprising N RF transmitters, where N is a positive integer; b. one
RF receiver provided with at least one directional antenna; c.
means for attaching said RF transmitter array to at least one
surgical tool; and, d. a computerized operating system adapted to
record the received signal strength (RSS) received by each antenna
of said RF receiver and to calculate therefrom the position of each
of said N RF transmitters, and further adapted to provide
automatically the results of said calculation to the human operator
of said interface; wherein said computerized operating system
calculates at least one of the parameters chosen from the group
consisting of (a) the angle from which the signal had been
received; (b) the spatial location of said at least one surgical
tool; (c) the path of said at least one surgical tool; (d) the
spatial location of the point of insertion of said at least one
surgical tool into the body of a patient; (e) the spatial location
of the tip of said at least one surgical tool; (f) matching each RF
transmitter code with each calculated spatial location of said at
least one surgical tool and/or said tip of said at least one
surgical tool, and further wherein said computerized operating
system performs said calculations and provides automatically the
results of said calculations to the human operator of said
interface.
62. The two-part robotic device of claim 61, additionally
comprising an endoscopic device and an interface for locating said
endoscopic device.
63. The two-part robotic device of claim 61, additionally
comprising an interface for locating the endoscope, wherein said
endoscopic device comprises optical imaging means, and further
wherein said computerized operating system calculates at least one
of the parameters chosen from the group consisting of (a) the
spatial location of said at least one surgical tool; (b) the path
of said at least one surgical tool; (c) the spatial location of the
point of insertion of said at least one surgical tool into the body
of a patient; (d) the spatial location of the tip of said at least
one surgical tool; (e) matching each RF transmitter code with each
calculated spatial location of said at least one surgical tool
and/or said tip of said at least one surgical tool; (f) the
predicted appearance of said at least one surgical tool within said
optical image; and (g) distinguishing among at least two surgical
tools appearing in said optical image in the case that more than
one surgical tool appears in said optical image; and further
wherein said computerized operating system provides automatically
the results of said calculation to the human operator of said
interface.
64. The two-part robotic device of claim 61, additionally
comprising an interface for locating said endoscope, further
comprising: a. an automated assistant for said endoscopic device;
and, b. means for interfacing said computerized operating system to
said automated assistant; wherein said computerized operating
system calculates at least one of the parameters chosen from the
group consisting of (a) the spatial location of said at least one
surgical tool; (b) the path of said at least one surgical tool; (c)
the spatial location of the point of insertion of said at least one
surgical tool into the body of a patient; (d) the spatial location
of the tip of said at least one surgical tool; (e) matching each RF
transmitter code with each calculated spatial location of said at
least one surgical tool and/or said tip of said at least one
surgical tool; (f) a desired new location for said endoscopic
device; (g) command protocol means for directing said automated
assistant via said interface to maneuver said endoscopic device to
a desired new location, and further wherein said computerized
operating system provides automatically the results of said
calculation to the human operator of said interface.
65. The two-part robotic device of claim 47, additionally
comprising an interface for locating the endoscope, wherein said
endoscopic device comprises optical imaging means, and further
wherein said computerized operating system calculates at least one
of the parameters chosen from the group consisting of (a) the
spatial location of said at least one surgical tool; (b) the path
of said at least one surgical tool; (c) the spatial location of the
point of insertion of said at least one surgical tool into the body
of a patient; (d) the spatial location of the tip of said at least
one surgical tool; (e) matching each RF transmitter code with each
calculated spatial location of said at least one surgical tool
and/or said tip of said at least one surgical tool; (f) the
predicted appearance of said at least one surgical tool within said
optical image; (g) if more than one of said at least one surgical
tools appears simultaneously in said optical image, distinguishing
among said more than at least surgical tools appearing in said
optical image; (h) a desired new location for said optical imaging
means; (i) a command protocol for directing said automated
assistant via said interface to maneuver said endoscopic device to
a desired new location, and further wherein said computerized
operating system provides automatically the results of said
calculation to the human operator of said interface.
66. The two-part robotic device of claim 47, additionally
comprising an interface for locating the endoscope, wherein said
computer controller additionally transmits a command protocol to
said automated assistant via said interface to maneuver said
endoscopic device to a desired new location.
67. The two-part robotic device of claim 43, additionally
comprising an interface for locating the endoscope, wherein said
interface is adapted for manual operation, whereby each of said N
transmitters transmits in response to a command signal from the
human operator of the interface.
68. The two-part robotic device of claim 43, additionally
comprising an interface for locating the endoscope, wherein said
interface is adapted for automatic operation, whereby each of said
N transmitters transmits continuously.
69. The two-part robotic device of claim 43, additionally
comprising an interface for locating the endoscope, wherein said
interface is adapted for automatic operation, whereby each of said
N transmitters transmits continuously, and further wherein said
computer transmits said calculated parameters for each of said N
transmitters in response to a command signal from the human
operator of the interface.
70. The two-part robotic device of claim 43, additionally
comprising an interface for locating the endoscope, wherein said
antenna array comprises at least one directional antenna.
71. The two-part robotic device of claim 43, additionally
comprising an interface for locating the endoscope, wherein said
receiver array is adapted to determine the angle whose vertex is
the location of said antenna array and which is subtended by the
line connecting any two of said N transmitters.
72. The two-part robotic device of claim 43, additionally
comprising an interface for locating the endoscope, wherein said
interface comprises M receivers, M is an integer higher than 1; and
further wherein said M receivers are adapted to determine the
location of each of said N transmitters by triangulation.
73. The two-part robotic device of claim 43, additionally
comprising an interface for locating the endoscope, wherein said
transmitters transmit in the 430 MHz ISM band.
74. The two-part robotic device of claim 43, additionally
comprising an interface for locating the endoscope, wherein said
transmitters transmit a modulated signal, said modulation chosen
from the group consisting of (a) frequency modulation, (b)
amplitude modulation.
75. The method according to claim 58, additionally comprising an
interface for locating the endoscope, wherein said modulation
occurs at a frequency of about 1.5 kHz.
76. The method according to claim 58, wherein each of said N RF
transmitters is modulated at a different frequency.
77. The two-part robotic device of claim 60, additionally
comprising an interface for locating the endoscope, wherein said N
modulation frequencies are chosen from the band of frequencies
spanning the range of from about 1.0 kHz to about 1.5 kHz.
78. The two-part robotic device of claim 43, additionally
comprising an interface for locating the endoscope, wherein said
receiver is a single conversion receiver.
79. The method according to claim 58, additionally comprising step
of calculating positional parameters of a laparoscopic surgical
tool.
80. The method according to claim 79, wherein said step of
calculating additionally comprises steps of: a. obtaining an
interface for a laparoscope, said interface comprising (i) at least
one array comprising N RF transmitters, where N is a positive
integer, (ii) one RF receiver provided with at least one
directional antenna; (iii) a computerized operating system adapted
to record the received signal strength RSS received by each antenna
of said RF receiver and to calculate therefrom the position of each
of said N RF transmitters, and further adapted to provide
automatically the results of said calculation to the human operator
of said interface; b. obtaining a surgical tool; c. attaching said
RF transmitter array to said surgical tool; d. measuring the
received signal strength (RSS) from said N RF transmitters received
at each of said directional antenna of said RF receivers; e.
calculating spatial parameters relating to each of said N
transmitters according to a predetermined protocol; wherein said
step of calculating said parameters of each of said N transmitters
yields positional parameters of said laparoscope surgical tool,
said positional parameters is selected from a group consisting of
(a) the angle from which the signal had been received; (b) the
spatial location of said at least one surgical tool; (c) the path
of said at least one surgical tool; (d) the spatial location of the
point of insertion of said at least one surgical tool into the body
of a patient; (e) the spatial location of the tip of said at least
one surgical tool; (f) matching each RF transmitter code with each
calculated spatial location of said at least one surgical tool
and/or said tip of said at least one surgical tool, and further
wherein said computerized operating system provides automatically
the results of said calculation to the human operator of said
interface.
81. The method according to claim 80, for controlling the position
of an endoscopic device, additionally comprising the steps of: a.
obtaining an interface between a surgeon and an automated
assistant, said interface comprising (i) at least one array
comprising N RF transmitters, where N is a positive integer, (ii)
one RF receiver provided with at least one directional antenna;
(iii) a computerized operating system adapted to record the
received signal strength RSS received by each antenna of said RF
receiver and to calculate therefrom the position of each of said N
RF transmitters, and further adapted to provide automatically the
results of said calculation to the human operator of said
interface; (iv) an automated assistant for said endoscopic device;
and, (v) means for interfacing said computerized operating system
to said automated assistant; b. obtaining a surgical tool; c.
attaching said RF transmitter array to said surgical tool; d.
measuring the received signal strength (RSS) from said N RF
transmitters received at each of said directional antenna of said
RF receivers; e. calculating spatial parameters relating to each of
said N transmitters according to a predetermined protocol; f.
calculating a desired new position for said endoscopic device; g.
sending a command from said computerized operating system to said
automated assistant via said interfacing means to maneuver said
endoscopic device to said desired new location; and, h. maneuvering
said endoscopic device to said desired new location; wherein said
step of calculating said parameters of each of said N transmitters
yields positional parameters of said laparoscope surgical tool,
said positional parameters is selected from a group consisting of
(a) the angle from which the signal had been received; (b) the
spatial location of said at least one surgical tool; (c) the path
of said at least one surgical tool; (d) the spatial location of the
point of insertion of said at least one surgical tool into the body
of a patient; (e) the spatial location of the tip of said at least
one surgical tool; (f) matching each RF transmitter code with each
calculated spatial location of said at least one surgical tool
and/or said tip of said at least one surgical tool, and further
wherein said computerized operating system provides automatically
the results of said calculation to the human operator of said
interface.
82. The method of claim 81, wherein said endoscopic device
comprises optical imaging means, and further comprising additional
steps of a. determining said position of said surgical tool
relative to the image frame according to a predetermined protocol;
and, b. maneuvering said optical imaging means such that said
surgical tool appears at a predetermined location within said image
frame.
83. The method of claim 78, wherein each of said N transmitters
transmits in response to a signal from the human operator of said
interface.
84. The method of claim 78, wherein each of said N transmitters
transmits continuously.
85. The two-part robotic device of claim 61, additionally
comprising an interface for locating the endoscope, wherein said
receiver is a single conversion receiver.
Description
FIELD OF THE INVENTION
[0001] The present invention relates to a method and apparatus for
laparoscopic surgery using a two-part device composed of a base
unit and a detachable body unit. The invention furthermore relates
to the guiding of such laparoscopic instruments and procedures, and
in particular to interfaces that allow identification of the
spatial position of a laparoscope during endoscopic surgery.
BACKGROUND OF THE INVENTION
[0002] In laparoscopic surgery, the surgeon performs the operation
through one or more small incisions using long instruments, while
observing the internal anatomy with an endoscope camera. The
laparoscope is often provided with some form of gantry or holding
unit to hold the external portion of the device in place. This
gantry is often a somewhat cumbersome apparatus and is in general
associated with a particular laparoscopic device. Each form of
surgical laparoscope will have its own gantry which must be
installed before use.
[0003] For example U.S. Pat. No. 5,878,193 provides a robotic
system that moves a surgical instrument in response to the
actuation of a control panel that can be operated by the surgeon.
The robotic system has an end effector that is adapted to hold a
surgical instrument such as an endoscope. The end effector is
coupled to a robotic arm assembly which can move the endoscope
relative to the patient. The system includes a computer which
controls the movement of the robotic arm in response to input
signals received from the control panel. The robotic system is
mounted to a cart which can be wheeled to and from an operating
table.
[0004] An example of laparoscopic surgery is Functional Endoscopic
Sinus Surgery (FESS) used to relieve blockages and discomfort in
the nasal sinuses--a commonly performed operation.
[0005] During laparoscopic surgery it is often required to shift
the spatial placement of the endoscope in order to present the
surgeon with an optimal view. Conventional laparoscopic surgery
makes use either of human assistants who manually shift the
instrumentation or alternatively of robotic automated assistants.
Automated assistants utilize interfaces that enable the surgeon to
direct the mechanical movement of the assistant, achieving a shift
in the camera view. U.S. Pat. No. 6,714,841 discloses an automated
camera endoscope in which the surgeon is fitted with a head mounted
light source that transmits his head movements to a sensor, forming
an interface that converts said movements to directions for the
mechanical movement of the automated assistant. Alternative
automated assistants incorporate a voice operated interface, a
directional key interface, or other navigational interfaces. The
main disadvantage of the above interfaces is that they are based on
cumbersome operations for starting and stopping movement directions
that requires the surgeon's constant attention.
[0006] Arshak's article "A Model for Estimating the Real Time
Positions of a Moving Object in Wireless Telemetry Applications
Using RF Sensors" (Arshak, K.; Adepoju, F. Sensors Applications
Symp. 2007, 1-6) relates to a method for locating a transmitting
object using multiple receiving antenna sensors located at various
place surrounding the transmitting device. The receiver antennas
are assumed to be omni-directional and the location of the
transmitter is achieved through distance estimation (i.e.,
triangulation) from each of the receiving antennae.
[0007] The distance from the transmitter is estimated by measuring
the received signal strength (RSS) of the received signal, where
the estimated RSS (in dB) is given by the following equation:
RSS=PT-PL(d.sub.0)-10.eta. log.sub.10(d/d.sub.i)+X.sub..sigma.
where PT is the transmitted power, PL(d.sub.0) is the path loss for
a reference distance d.sub.0, .eta. is the pass loss exponent, d is
the distance between the transmitter and the receiver, and
X.sub..sigma. is a Gaussian random variable.
[0008] Therefore, the signal received is proportional to PT and the
.eta..sup.th power of distance to the transmitter. In free space,
.eta. is normally equal to 2. The location of the transmitter can
thus be determined by using the above equation to calculate the
distance to each of the receiving antennas and triangulating.
Arshak states in the article that other methods such as time of
arrival, time differences of arrival and angle of arrival are not
feasible in dense, multipath environments. If, however, the
transmission power is unknown, unstable or inaccurate, or if the
propagation factor is unknown, then Arshak's method cannot be used.
An efficient method for enabling the relative position of the
transmitter (and thus the medical instrument) to be determined
therefore remains a long-felt need.
[0009] Research has suggested that these systems divert the
surgeon's focus from the major task at hand. Therefore technologies
based on various kinds of positioning systems have been developed
to simplify interfacing control. These technologies still fail to
address another complicating interface aspect of laparoscopic
surgery, however, as they do not allow the surgeon to signal both
to the automated assistant and to surgical colleagues on which
surgical instrument his attention is focused.
[0010] Hence, a system for laparoscopic surgery providing multiple
laparoscopic tools while employing a single external holding device
is a long felt need, especially in the field of sinus surgery.
Additionally there is a further long-felt need for a device that
would allow the surgeon to identify to the laparoscopic computing
system as well as to surgical colleagues to which surgical
instrument attention is to be directed, thereby directing the view
provided by the endoscope to the selected area of interest.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] In order to understand the invention and to see how it may
be implemented in practice, a plurality of embodiments will now be
described, by way of non-limiting example only, with reference to
the accompanying drawings, in which
[0012] FIG. 1 presents a Universal Joint, also known as the U-joint
or Cardan joint;
[0013] FIG. 2 presents a constant-velocity or CV joint;
[0014] FIG. 3 presents a Thompson joint, this being a type of
double Cardan joint;
[0015] FIG. 4 presents a plan view of an embodiment of the variable
coupling of the present invention;
[0016] FIG. 5 presents an isometric view of an embodiment of the
variable coupling of the present invention;
[0017] FIG. 6 presents an isometric view of a second embodiment of
the variable coupling of the present invention;
[0018] FIG. 7 presents a different isometric view of the second
embodiment of the variable coupling of the present invention;
[0019] FIG. 8 presents a series of three of the variable couplings
of the present invention in series;
[0020] FIG. 9 presents a two-wheel-drive bicycle with front and
rear suspension and no chain, based on the coupling of the instant
invention;
[0021] FIG. 10 presents a robotic arm based on the coupling of the
current invention;
[0022] FIG. 11 presents a laparoscopic instrument based on the
coupling of the current invention;
[0023] FIG. 12 presents another laparoscopic instrument based on
the coupling of the current invention;
[0024] FIG. 13 presents another laparoscopic instrument based on
the coupling of the current invention;
[0025] FIG. 14 presents another laparoscopic instrument based on
the coupling of the current invention;
[0026] FIG. 15 presents a laparoscopic instrument based on the
coupling of the current invention in use during surgery;
[0027] FIG. 16 presents a laparoscopic instrument based on the
coupling of the current invention in use during surgery;
[0028] FIGS. 17-18 present a laparoscopic instrument based on the
coupling of the current invention in use during surgery;
[0029] FIG. 19 shows the main and the preferred embodiment of the
present invention which incorporates the positioning elements of
FIGS. 15-18;
[0030] FIG. 20 illustrates a second embodiment of the present
invention in which two consecutive tubular members are
employed;
[0031] FIG. 21 shows a cross section of the tubular sections shown
in FIG. 20;
[0032] FIG. 22 illustrates an embodiment of the device in use;
[0033] FIG. 23 illustrates various possible motions of the
device;
[0034] FIG. 24 illustrates various possibilities for operation of
the device;
[0035] FIG. 25 illustrates a general schematic view of (a) surgical
tool positioning system that detects the location of a surgical
tool at the time the surgeon activates the surgical tool
transmitter (manual mode) and (b) surgical tool positioning system
that detects the location of surgical tools continuously
(continuous automatic mode);
[0036] FIG. 26 schematically illustrates (a) sequential transmit
operation, (b) periodic transmit operation, with unequal rates for
left and right transmitters and (c) simultaneous transmit operation
with different frequencies;
[0037] FIG. 27 schematically illustrates a view of the antenna
pattern;
[0038] FIG. 28 shows block diagrams of (a) the location system, (b)
an antenna set, (c) the internal receiver and (d) the
controller/sequencer;
[0039] FIG. 29 shows system control software operation flow;
[0040] FIG. 30 shows the antenna switching pattern during (a)
periodic transmit operation and (b) sequential transmit
operation;
[0041] FIG. 31 shows examples of planar and spatial antenna
structures;
[0042] FIG. 32 shows examples of the use of the location system in
(a) abdominal laparoscopic surgery and (b) knee endoscopic
surgery;
[0043] FIG. 36 shows aspects of the invention particularly suited
for sinus surgery;
[0044] FIG. 42 shows an additional embodiment of the invention as
used during sinus surgery;
[0045] FIG. 43 illustrates the various degrees of freedom available
to an end effector attached to the invention;
[0046] FIG. 44 illustrates means for rotating an end effector in a
plane about the long axis of the output shaft (DOF.sub.1);
[0047] FIG. 45 illustrates means for effecting motion about degree
of freedom DOF.sub.2 and the bearing that allows motion about
degree of freedom DOF.sub.3 independent of motion about degree of
freedom DOF.sub.2;
[0048] FIG. 46 illustrates the relationships between means for
effecting motion about degree of freedom DOF.sub.2 and means for
effecting motion about degree of freedom DOF.sub.3;
[0049] FIG. 47 illustrates modeling of the motion of a surgical
device attached to the invention as the motion of a bead rotating
in space;
[0050] FIG. 48 presents an illustration of the drive means for
effecting motion about degree of freedom DOF.sub.4;
[0051] FIG. 49 presents an illustration of the drive means for
effecting motion about degrees of freedom DOF.sub.5 and
DOF.sub.6;
[0052] FIG. 50 presents a detailed illustration of means for
effecting translational motion about degree of freedom DOF.sub.5;
and
[0053] FIG. 51 presents a detailed illustration of means for
effecting translational motion about degree of freedom
DOF.sub.6.
SUMMARY OF THE INVENTION
[0054] It is an object of the invention to provide a laparoscope
composed of a set of detachable parts. A base unit attaches to a
fixed location such as the floor, the side of an operating table,
or the like. A body unit attaches to this base unit and is provided
with a laparoscope and associated devices, such as surgical tools,
camera, fiber optics, light sources, and the like. The body unit
attaches easily to the base unit and is supported by it during
surgery. It may be detached and replaced with another body unit
suitable for different procedures. The device utilizes a novel
torque-transmitting joint that allows a large number of degrees of
freedom to be transmitted while allowing the several sections of
the device to be rotated and translated through additional degrees
of freedom. In this way a simple and modular means for performing a
wide variety of surgical procedures is attained.
[0055] It is thus an object of the present invention to disclose a
two-part robotic device for positioning of a hand tool, comprising
(a) a fixed base unit constantly fix to its position; and (b) a
detachable body unit reversibly coupled to said fixed base unit,
coupled to said current medical instrument. It is within the
essence of the invention wherein said fixed base unit is adapted to
provide independent movement to said hand tool, said independent
movement selected from the group consisting of rotation and
translation, and further wherein said detachable body unit is
removable and replaceable from said fixed base unit such that upon
exchange of said hand tool for a second hand tool, said second hand
tool is placed in substantially the same location as the location
of said hand tool prior to said exchange. It is a further object of
the present invention to disclose such a two-part robotic device,
wherein said hand tool is a medical instrument.
[0056] It is another object of the present invention to provide the
two-part robotic device as defined above, wherein said medical
instrument is selected from a group consisting of endoscope,
laparoscope, forceps, or any combination thereof.
[0057] It is another object of the present invention to provide the
two-part robotic device as defined above, wherein said detachable
unit is an endoscope positioning device adapted to provide said
endoscope at least 7 DOF selected from a group consisting of at
least 6 rotation movements (1007, 1009, 1010, 1011, 1012, 1013,
1601, 1602), at least 1 translation movement (1008) or any
combination thereof.
[0058] It is another object of the present invention to provide the
two-part robotic device as defined above, wherein said detachable
unit comprises: [0059] a. k consecutive arm sections, each
comprising n coaxial input shafts adapted to be rotated around an
input axis of rotation by in sources of torque, where n and m and k
are positive integers; said current instrument is coupled to one of
said k consecutive arm sections; [0060] b. at least k-1 constant
velocity couplers coupling each two of said k consecutive arm
sections together, each of said constant velocity coupler
comprising: [0061] i. n coaxial input transmission means, each of
which is coupled to one of said n input shafts; said input
transmission means defining a first plane substantially
perpendicular to said input axis of rotation; [0062] ii. n coaxial
second transmission means rotatably connected to said n input
transmission means; said second transmission means rotating in a
second plane, such that said second plane is substantially
perpendicular to said first plane; [0063] iii. n coaxial output
transmission means rotatably connected to said n second
transmission means; said output transmission means rotating in a
third plane; said third plane being substantially perpendicular to
said second plane; [0064] c. n coaxial output shafts, each of which
is coupled to one of said n output transmission means, said n
output shafts being adapted to rotate around an output axis of
rotation; such that (i) turning a given input shaft at a constant
velocity will provide a constant velocity at the corresponding
output shaft; and, (ii) the angle between said input axis of
rotation and said output axis of rotation varies in said second
plane in an angular range of about 0 to about 360 degrees.
[0065] It is another object of the present invention to provide the
two-part robotic device as defined above, wherein said fixed base
unit comprises: [0066] a. k consecutive arm sections, each
comprising n coaxial input shafts adapted to be rotated around an
input axis of rotation by m sources of torque, where n and m and k
are positive integers; said current instrument is coupled to one of
said k consecutive arm sections; [0067] b. at least k-1 constant
velocity couplers coupling each two of said k consecutive arm
sections together, each of said constant velocity coupler
comprising: [0068] i. n coaxial input transmission means, each of
which is coupled to one of said n input shafts; said input
transmission means defining a first plane substantially
perpendicular to said input axis of rotation; [0069] ii. n coaxial
second transmission means rotatably connected to said n input
transmission means; said second transmission means rotating in a
second plane, such that said second plane is substantially
perpendicular to said first plane; [0070] iii. n coaxial output
transmission means rotatably connected to said n second
transmission means; said output transmission means rotating in a
third plane; said third plane being substantially perpendicular to
said second plane; [0071] c. n coaxial output shafts, each of which
is coupled to one of said n output transmission means, said n
output shafts being adapted to rotate around an output axis of
rotation; such that (i) turning a given input shaft at a constant
velocity will provide a constant velocity at the corresponding
output shaft; and, (ii) the angle between said input axis of
rotation and said output axis of rotation varies in said second
plane in an angular range of about 0 to about 360 degrees.
[0072] It is another object of the present invention to provide the
two-part robotic device as defined above, wherein said input
transmission means, second transmission means, and said output
transmission means are selected from a group consisting of
gearwheels, wheels, crown gears, bevel gears, spur gears, belts, or
any combination thereof.
[0073] It is another object of the present invention to provide the
two-part robotic device as defined above, additionally comprising
[0074] a. an axial support member (601) adapted to provide axial
support to said n output shafts in said third plane; and, [0075] b.
a circular track (618) centered on the axis of rotation of said
second transmission means, said axial support member being adapted
to fit into said track and slide within it.
[0076] It is another object of the present invention to provide the
two-part robotic device as defined above, additionally comprising a
radial support member (604) adapted to provide radial support to
said n output shafts, said radial support member being adapted to
rotate in said second plane.
[0077] It is another object of the present invention to provide the
two-part robotic device as defined above, wherein the gear ratio
between said input and output shafts is between about 10 and about
0.1.
[0078] It is another object of the present invention to provide the
two-part robotic device as defined above, additionally comprising n
coaxial auxiliary shafts in rotating communication with said n
second transmission means, said n coaxial auxiliary shafts rotating
in said second plane, and said n coaxial auxiliary shafts capable
of either being driven by said input shafts or driving said input
shafts.
[0079] It is another object of the present invention to provide the
two-part robotic device as defined above, additionally comprising
locking means adapted for preventing relative movement between one
or more of said input axis shafts and said constant velocity joint,
wherein said constant velocity joint is caused to rotate as a body
with said locked input axis shafts.
[0080] It is another object of the present invention to provide the
two-part robotic device as defined above, additionally comprising
locking means for preventing relative movement between one or more
of said output axis shafts and said constant velocity joint,
wherein said constant velocity joint is caused to rotate as a body
with said locked output axis shafts.
[0081] It is another object of the present invention to provide the
two-part robotic device as defined above, adapted for use in sinus
surgery.
[0082] It is another object of the present invention to provide the
two-part robotic device as defined above, wherein said sinus
surgery is FESS.
[0083] It is another object of the present invention to provide a
method for altering a current medical instrument in use whilst
performing a laparoscopic surgery. The method comprises steps of:
[0084] a. providing a two-part robotic device comprising: [0085] i.
a fixed base unit, constantly fix to its position; [0086] ii. a
detachable body unit reversibly coupled to said fixed base unit,
comprising said current medical instrument; [0087] b. coupling said
detachable body unit to said fixed base; [0088] c. providing
independent movements to said current medical instrument selected
from a group consisting of rotation and translation; thereby
performing said laparoscopic surgery; [0089] d. detaching said
detachable body unit from said fixed base unit; and, [0090] e.
replacing said current medical instrument in said detachable body
unit thereby altering said current medical instrument.
[0091] It is a further object of the present invention to provide a
method of altering the modality of a laparoscopic surgery. The
method comprises steps of: [0092] a. providing a two-part robotic
device comprising: [0093] iii. a fixed base unit, constantly fix to
its position; [0094] iv. a first detachable body unit reversibly
coupled to said fixed base unit, comprising said current medical
instrument; said first detachable body unit is adapted for
laparoscopic surgery of a first modality; [0095] b. coupling said
first detachable body unit to said fixed base; [0096] c. providing
independent movements to said current medical instrument selected
from a group consisting of rotation and translation; thereby
performing said laparoscopic surgery of said first modality with
said first detachable body unit; [0097] d. providing a second
detachable body unit adapted for laparoscopic surgery of a second
modality; [0098] e. decoupling said first detachable body unit from
said fixed base; [0099] f. coupling said second detachable body
unit for laparoscopic surgery of a second modality; [0100] g.
performing laparoscopic surgery of said second modality with said
second detachable body unit; thereby altering the modality of said
laparoscopic surgery.
[0101] It is a further object of the present invention to disclose
an interface between a surgeon and an automated assistant,
comprising (a) at least one array comprising N RF transmitters,
where N is a positive integer; (b) one RF receiver, provided with
at least one directional antenna; (c) means for attaching said RF
transmitter array to at least one surgical tool; and, (d) a
computerized operating system adapted to record the received signal
strength (RSS) received by said RF receiver and to calculate
therefrom the position of each of said N RF transmitters, and
further adapted to provide automatically the results of said
calculation to the human operator of said interface. It is within
the essence of the invention wherein said computerized operating
system calculates at least one of the parameters chosen from the
group consisting of (a) the angle from which the signal had been
received; (b) the spatial location of said at least one surgical
tool; (c) the path of said at least one surgical tool; (d) the
spatial location of the point of insertion of said at least one
surgical tool into the body of a patient; (e) the spatial location
of the tip of said at least one surgical tool; (f) matching each RF
transmitter code with each calculated spatial location of said at
least one surgical tool and/or said tip of said at least one
surgical tool, and further wherein said computerized operating
system provides automatically the results of said calculation to
the human operator of said interface.
[0102] It is a further object of this invention to disclose such an
interface, further comprising an endoscopic device.
[0103] It is a further object of this invention to disclose such an
interface, wherein said endoscopic device comprises optical imaging
means, and further wherein said computerized operating system
calculates at least one of the parameters chosen from the group
consisting of (a) the spatial location of said at least one
surgical tool; (b) the path of said at least one surgical tool; (c)
the spatial location of the point of insertion of said at least one
surgical tool into the body of a patient; (d) the spatial location
of the tip of said at least one surgical tool; (e) matching each RF
transmitter code with each calculated spatial location of said at
least one surgical tool and/or said tip of said at least one
surgical tool; (f) the predicted appearance of said at least one
surgical tool within said optical image; (g) if more than one of
said at least one surgical tools appears simultaneously in said
optical image, distinguishing among said more than at least
surgical tools appearing in said optical image, and further wherein
said computerized operating system provides automatically the
results of said calculation to the human operator of said
interface.
[0104] It is a further object of this invention to disclose such an
interface, further comprising (a) a automated assistant for said
endoscopic device; and (b) means for interfacing said computerized
operating system to said automated assistant: It is within the
essence of the invention wherein said computerized operating system
calculates at least one of the parameters chosen from the group
consisting of (a) the spatial location of said at least one
surgical tool; (b) the path of said at least one surgical tool; (c)
the spatial location of the point of insertion of said at least one
surgical tool into the body of a patient; (d) the spatial location
of the tip of said at least one surgical tool; (e) matching each RF
transmitter code with each calculated spatial location of said at
least one surgical tool and/or said tip of said at least one
surgical tool; (f) a desired new location for said endoscopic
device; (g) command protocol means for directing said automated
assistant via said interface to maneuver said endoscopic device to
a desired new location, and further wherein said computerized
operating system provides automatically the results of said
calculation to the human operator of said interface.
[0105] It is a further object of this invention to disclose such an
interface, wherein said endoscopic device comprises optical imaging
means, and further wherein said computerized operating system
calculates at least one of the parameters chosen from the group
consisting of (a) the spatial location of said at least one
surgical tool; (b) the path of said at least one surgical tool; (c)
the spatial location of the point of insertion of said at least one
surgical tool into the body of a patient; (d) the spatial location
of the tip of said at least one surgical tool; (e) matching each RF
transmitter code with each calculated spatial location of said at
least one surgical tool and/or said tip of said at least one
surgical tool; (f) the predicted appearance of said at least one
surgical tool within said optical image; (g) if more than one of
said at least one surgical tools appears simultaneously in said
optical image, distinguishing among said more than at least
surgical tools appearing in said optical image; (h) a desired new
location for said optical imaging means; (i) a command protocol for
directing said automated assistant via said interface to maneuver
said endoscopic device to a desired new location, and further
wherein said computerized operating system provides automatically
the results of said calculation to the human operator of said
interface.
[0106] It is a further object of this invention to disclose such an
interface, wherein said computer controller additionally transmits
a command protocol to said automated assistant via said interface
to maneuver said endoscopic device to a desired new location.
[0107] It is a further object of this invention to disclose such an
interface, wherein said interface is adapted for manual operation,
whereby each of said N transmitters transmits in response to a
command signal from the human operator of the interface.
[0108] It is a further object of this invention to disclose such an
interface, wherein said interface is adapted for automatic
operation, whereby each of said N transmitters transmits
continuously.
[0109] It is a further object of this invention to disclose such an
interface, wherein said interface is adapted for automatic
operation, whereby each of said N transmitters transmits
continuously and further wherein said computer transmits said
calculated parameters for each of said N transmitters in response
to a command signal from the human operator of the interface.
[0110] It is a further object of this invention to disclose such an
interface, wherein said antenna array comprises at least one
directional antenna.
[0111] It is a further object of this invention to disclose such an
interface, wherein said transmitters transmit in the 430 MHz ISM
band.
[0112] It is a further object of this invention to disclose such an
interface, wherein M =1, and further wherein said receiver array is
adapted to determine the angle whose vertex is the location of said
antenna array and which is subtended by the line connecting any two
of said N transmitters.
[0113] It is a further object of this invention to disclose such an
interface, wherein said interface comprises M receivers, M is an
integer higher than 1; and further wherein said M receivers are
adapted to determine the location of each of said N transmitters by
triangulation.
[0114] It is a further object of this invention to disclose such an
interface, wherein said transmitters transmit a modulated signal,
said modulation chosen from the group consisting of (a) frequency
modulation, (b) amplitude modulation.
[0115] It is a further object of this invention to disclose such an
interface, wherein said modulation occurs at a frequency of about
1.5 kHz.
[0116] It is a further object of this invention to disclose such an
interface, wherein each of said N RF transmitters is modulated at a
different frequency.
[0117] It is a further object of this invention to disclose such an
interface, wherein said N modulation frequencies are chosen from
the band of frequencies spanning the range of from about 1.0 kHz to
about 1.5 kHz.
[0118] It is a further object of this invention to disclose such an
interface, wherein receiver is a single conversion receiver.
[0119] It is a further object of this invention to disclose a
method for calculating positional parameters of a laparoscopic
surgical tool, comprising the steps of (a) obtaining an interface
for a laparoscope, said interface comprising (i) at least one array
comprising N RF transmitters, where N is a positive integer, (ii)
one RF receiver provided with at least one directional antenna;
(iii) a computerized operating system adapted to record the
received signal strength RSS received by each antenna of said RF
receiver and to calculate therefrom the position of each of said N
RF transmitters, and further adapted to provide automatically the
results of said calculation to the human operator of said
interface; (b) obtaining a surgical tool; (c) attaching said RF
transmitter array to said surgical tool; (d) measuring the received
signal strength (RSS) from said N RF transmitters received at each
of said directional antenna of said RF receivers; and (e)
calculating spatial parameters relating to each of said N
transmitters according to a predetermined protocol. It is in the
essence of the invention wherein said step of calculating said
parameters of each of said N transmitters yields positional
parameters of said laparoscope surgical tool, said positional
parameters is selected from a group consisting of (a) the angle
from which the signal had been received; (b) the spatial location
of said at least one surgical tool; (c) the path of said at least
one surgical tool; (d) the spatial location of the point of
insertion of said at least one surgical tool into the body of a
patient; (e) the spatial location of the tip of said at least one
surgical tool; (f) matching each RF transmitter code with each
calculated spatial location of said at least one surgical tool
and/or said tip of said at least one surgical tool, and further
wherein said computerized operating system provides automatically
the results of said calculation to the human operator of said
interface.
[0120] It is a further object of this invention to disclose a
method for controlling the position of an endoscopic device,
comprising the steps of (a) obtaining an interface between a
surgeon and an automated assistant, said interface comprising (i)
at least one array comprising N RF transmitters, where N is a
positive integer, (ii) one RF receiver provided with at least one
directional antenna; (iii) a computerized operating system adapted
to record the received signal strength RSS received by each antenna
of said RF receiver and to calculate therefrom the position of each
of said N RF transmitters, and further adapted to provide
automatically the results of said calculation to the human operator
of said interface; (iv) an automated assistant for said endoscopic
device; and, (v) means for interfacing said computerized operating
system to said automated assistant; (b) obtaining a surgical tool;
(c) attaching said RF transmitter array to said surgical tool; (d)
measuring the received signal strength (RSS) from said N RF
transmitters received at each of said directional antenna of said
RF receivers; (e) calculating spatial parameters relating to
location of each of said N transmitters; (f) calculating a desired
new position for said endoscopic device; (g) sending a command from
said computerized operating system to said automated assistant via
said interfacing means to maneuver said endoscopic device to said
desired new location; and, (h) maneuvering said endoscopic device
to said desired new location
[0121] It is in the essence of the invention wherein said step of
calculating said parameters of each of said N transmitters yields
positional parameters of said laparoscope surgical tool, said
positional parameters is selected from a group consisting of (a)
the angle from which the signal had been received; (b) the spatial
location of said at least one surgical tool; (c) the path of said
at least one surgical tool; (d) the spatial location of the point
of insertion of said at least one surgical tool into the body of a
patient; (e) the spatial location of the tip of said at least one
surgical tool; (0 matching each RF transmitter code with each
calculated spatial location of said at least one surgical tool
and/or said tip of said at least one surgical tool, and further
wherein said computerized operating system provides automatically
the results of said calculation to the human operator of said
interface.
[0122] It is a further object of this invention to disclose such an
interface, wherein said endoscopic device comprises optical imaging
means, and further comprising the additional steps of (a)
determining said position of said surgical tool relative to the
image frame; and (b) maneuvering said optical imaging means such
that said surgical tool appears at a predetermined location within
said image frame.
[0123] It is a further object of this invention to provide such a
method, wherein each of said N transmitters transmits in response
to a signal from the human operator of said interface.
[0124] It is a further object of this invention to provide such a
method, wherein each of said N transmitters transmits
continuously.
[0125] The device of the present invention has many technological
advantages, among them simplification of the communication
interface between surgeon and automated assistants; seamless
interaction with conventional computerized automated endoscope
systems; simplicity of construction; reliability; and
user-friendliness. Additional features and advantages of the
invention will become apparent from the following drawings and
description.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0126] The following description is provided to enable any person
skilled in the art to make use of said invention and sets forth the
best modes contemplated by the inventor of carrying out this
invention. Various modifications, however, will remain apparent to
those skilled in the art, since the generic principles of the
present invention have been defined specifically to provide a
two-part endoscopic surgical device which is composed of a
positioning section (namely the endoscope/laparoscope) and a fixed
section (e.g., tubular arm) coupled to the bed of the patient. The
core concept of the present invention lies, in the fact that the
positioning section may be removed entirely from the fixed section
e.g. for replacement, repair, cleaning, etc. It will be apparent to
one skilled in the art that there are several embodiments of the
invention that differ in details of construction, without affecting
the essential nature thereof, and therefore the invention is not
limited by that which is illustrated in the figures and described
in the specification, but only as indicated in the accompanying
claims, with the proper scope determined only by the broadest
interpretation of said claims.
[0127] The present invention provides a two-part robotic device
used for exchanging the current medical instrument in used during
laparoscopic surgery. The device comprises (a) a fixed base unit;
and (b) a detachable body unit reversibly coupled to said fixed
base unit, comprising said current medical instrument.
[0128] It is emphasized that the detachable body unit is removable
and replaceable from said fixed base unit such that said current
medical instrument is altered.
[0129] The present invention provides a method for exchanging a
current medical instrument in used whilst performing a laparoscopic
surgery. The method comprises steps of: [0130] (a) providing a
two-part robotic device comprising: [0131] (i) a fixed base unit;
[0132] (ii) a detachable body unit reversibly coupled to said fixed
base unit, comprising said current medical instrument; [0133] (b)
coupling said detachable body unit to said fixed base; [0134] (c)
performing said laparoscopic surgery; [0135] (d) detaching said
detachable body unit from said fixed base unit; and, [0136] (e)
replacing said current medical instrument in said detachable body
unit thereby exchanging said current medical instrument.
[0137] In the following detailed description, numerous specific
details are set forth in order to provide a thorough understanding
of embodiments of the present invention. However, those skilled in
the art will understand that such embodiments may be practiced
without these specific details. Reference throughout this
specification to "one embodiment" or "an embodiment" means that a
particular feature, structure, or characteristic described in
connection with the embodiment is included in at least one
embodiment of the invention.
[0138] As used herein, the term "gear ratio" in a transmission with
an input shaft and an output shaft refers to the ratio of angular
velocity of the output shaft to that of the input shaft.
[0139] As used herein, the term "transmission means" refers to
means for transferring torque from one rotating element to another,
such as gearwheels, wheels, crown gears, and the like.
[0140] As used herein, the terms "endoscope" and "laparoscope"
refer interchangeably to a fiber optical device that consists of a
flexible tube. Glass or plastic filaments allow total internal
reflection of light for viewing. This medical device is used in
laparoscope, endoscope, laparoscopic and endoscopic surgeries. It
is also in the scope of the invention wherein the terms refer also
to any means for looking within body cavities, especially inside
the human body and mammalian body for medical reasons using an
instrument; and especially to means for minimally invasive
diagnostic medical procedure, such as rigid or flexible endoscopes,
fiberscopes, means for robotic surgery, trocars, surgical working
tools and diagnosing means etc.
[0141] As used herein, the terms "endoscopic surgery" and
"laparoscopic surgery" interchangeably refer to a modern surgical
technique in which operations upon the body of a patient, e.g.,
within the abdomen, are performed through small incisions (usually
0.5 to 1.5 cm) as compared to larger incisions needed in
traditional surgical procedures. Laparoscopic surgery includes
e.g., operations within the abdominal, pelvic or joint cavities.
Endoscopic surgery involves, inter alia, operations in the
gastrointestinal tract, e.g., in the esophagus, stomach and
duodenum (esophagogastroduodenoscopy), small intestine, colon
(colonoscopy, proctosigmoidoscopy), bile duct, endoscopic
retrograde cholangiopancreatography (ERCP), duodenoscope-assisted
cholangiopancreatoscopy, intraoperative cholangioscopy, the
respiratory tract, the nose (rhinoscopy), the lower respiratory
tract (bronchoscopy), the urinary tract (cystoscopy), the female
reproductive system, the cervix (colposcopy), the uterus
(hysteroscopy), the Fallopian tubes (falloscopy), normally closed
body cavities (through a small incision), the abdominal or pelvic
cavity (laparoscopy), the interior of a joint (arthroscopy) organs
of the chest (thoracoscopy and mediastinoscopy), the amnion during
pregnancy (amnioscopy), the fetus (fetoscopy), plastic surgery,
panendoscopy, laryngoscopy, esophagoscopy; and various non-medical
uses for endoscopy. The term also refers to any manipulation of
laparoscopes and endoscopes as defined above into the body of a
patient.
[0142] As used herein, the term "degrees of freedom" (DOF) refers
hereinafter to a set of independent displacements that specify
completely the displaced position of the endoscope or laparoscope
as defined above. In three dimensional space, there are six DOF,
three DOF of linear displacement and three rotational DOFs, namely,
moving up and down, moving left and right, moving forward and
backward, tilting up and down, turning left and right, tilting side
to side. The present invention refers to a system essentially
comprising means for providing a total of at least seven DOF (i.e.
DOF for components of a multiple-component system, wherein at least
a portion of the DOF of a given component are independent of those
of the other components of the system) selected from any of those
that will be described hereinafter.
[0143] As used herein, the term "distal portion" refers to the end
of the endoscope designed to be located within the body of the
patient while the endoscope is in use, and the term "proximal
portion" to the end of the endoscope designed to be located outside
the body of the patient while the endoscope is in use.
[0144] As used herein, the term "base unit" refers to a rigid unit
attached to a fixed point in space such as the floor, ceiling,
surgical table, or the like. The base is adapted to attach to a
laparoscope and transmit various necessary elements to and from it
including torques, light, voltages, video signals, and fluids.
[0145] As used herein, the term "body unit" refers to a
laparascopic surgical instrument adapted to attach to a base unit.
The base unit provides physical support to the body unit, which
must be able to maneuver in several dimensions and with several
degrees of freedom. The base unit transmits various necessary
elements to the body unit such as torques, voltages, fluids, etc.
The body unit generally comprises a laparoscopic instrument and
various positioning devices used to change its position and
direction.
[0146] As used herein, the term "automated assistant" refers to any
mechanical device (including but not limited to a robotic device)
that can maneuver and control the position of a surgical or
endoscopic instrument, and that can in addition be adapted to
receive commands from a remote source.
[0147] As used herein, the term "antenna gain" refers to the ratio
of the radiation intensity of an antenna in a given direction to
the intensity that would be produced by a hypothetical ideal
antenna that radiates equally in all directions (isotropically) and
has no losses.
[0148] As used herein, when referring to transmission of
information to a human, the term "provide" refers to any process
(visual, tactile, or auditory) by which an instrument, computer,
controller, or any other mechanical or electronic device can report
the results of a calculation or other operation to a human
operator.
[0149] As used herein, the term "automatic" or "automatically"
refers to any process that proceeds without the necessity of direct
intervention or action on the part of a human being.
[0150] Laparoscopic surgery, also called minimally invasive,
surgery (MIS), bandaid surgery, keyhole surgery, or pinhole surgery
is a modern surgical technique in which operations in the abdomen
are performed through small incisions (usually 0.5-1.5 cm) as
compared to larger incisions needed in traditional surgical
procedures. The key element in laparoscopic surgery is the use of a
laparoscope, which is a device adapted for viewing the scene within
the body, at the distal end of the laparoscope. Either an imaging
device is placed at the end of the laparoscope, or a rod lens
system or fiber optic bundle is used to direct this image to the
proximal end of the laparoscope. Also attached is a light source to
illuminate the operative field, inserted through a 5 mm or 10 mm
cannula or trocar to view the operative field. The abdomen is
usually insufflated with carbon dioxide gas to create a working and
viewing space. The abdomen is essentially blown up like a balloon
(insufflated), elevating the abdominal wall above the internal
organs like a dome. Within this space, various medical procedures
can be carried out. Thus more advanced laparoscopes perform more
than visual inspection, for instance performing various surgical
procedures such as hernia repair, prostatectomy, liver resection,
gastrectomy, and the like.
[0151] Generally the laparoscope is held fixed in some fashion,
either by an assistant, or on a mechanical support such as a
gantry, stand, or the like. For each laparoscopic procedure, in
general a different laparoscope is required. Due to the specialized
nature of these instruments, the support fixture for the device is
generally specific to the device and provided with it as a unit. In
order to save space, expense, and complexity, the present invention
provides a base unit that is rigidly supported. This base unit in
turn provides rigid support to the laproscope. The laparoscope is
detachable from the base unit in a modular fashion. Thus other
laparoscopic instruments can be attached to the same base station
for carrying out different surgeries. The base station is provided
with the necessary fixtures to allow operation of a variety of
laparoscopes, as will be detailed in the following.
[0152] For the performance of increasingly complex medical
procedures, a system for transmitting a large number of mechanical
degrees of freedom to the proximal end of a laparoscope is
desirable. The present invention solves this problem within the
constraints dictated by the nature of laparoscopic surgery, namely
a small incision diameter, a large distance between actuators
(outside the body) and actuated elements (within the body), and the
desire to provide the laparoscope with as many independent degrees
of freedom as possible.
[0153] The present invention provides a rigidly mounted base
station and a detachable body unit comprising a laparoscopic
surgical device. The main advantage in such a detachable body unit
lies in the fact that the fixed unit remains in place while the
detachable body (comprising the medical tool to be used) can be
altered quickly and easily.
[0154] Another key problem to be solved in laparoscopic surgeries
is providing the laparoscope with sufficient degrees of freedom. In
the device of the current invention this is solved using a novel
N-DOF (n degrees of freedom) torque transmitter based on a coaxial
constant-velocity joint. This joint will be described in the
following.
[0155] First we'll describe the coaxial constant-velocity joint and
then the coupling of such joint in a laparoscope for providing said
N-DOF. Lastly, the two-part robotic device comprising a medical
instrument (e.g. an endoscope integrated within it said coaxial
constant-velocity joints).
[0156] The N-DOF torque transmitter is provided with a series of
arms that contain multiple coaxial cylinders, each of which can
rotate independently. A novel joint allows two such cylindrical
devices to be mated while transmitting the rotations of the coaxial
members, allowing the two cylindrical devices to be pivoted with
respect to one another. The notion of concentric cylindrical
members is simple enough to forego detailed discussion, and thus in
the following we concentrate on the design of the joint joining two
such cylindrical members.
[0157] In many mechanical systems there arises the need to transfer
torque from an input shaft to an output shaft. A wide variety of
gear systems have been devised for this purpose. In a number of
important cases the output shaft must vary the direction of its
axis with respect to the input shaft. This is the case for example
in a front-wheel-drive car. The engine must provide torque to the
wheels, to move the car forward. However the front wheels must also
be allowed to change their axis of rotation, to allow steering of
the car.
[0158] The so-called universal joint, aka U-joint, Cardan joint,
Hardy-Spicer joint, or Hooke's joint is often employed for purposes
of allowing variation of the output axis direction. This is a joint
in a rigid rod that allows the rod to `bend`, and is commonly used
in shafts that transmit rotary motion. It consists of a pair of
ordinary hinges located close together, but oriented at 90.degree.
relative to each other. See FIG. 1a-1d for illustrations of this
common joint. The concept of the universal joint is based on the
design of gimbals, which have been in use since antiquity.
[0159] There are several known drawbacks to the simple U-joint.
When the two shafts are at an angle other than 180.degree.
(straight), the driven shaft does not rotate with constant angular
speed in relation to the drive shaft; as the angle approaches
90.degree. the output rotation gets jerkier (and furthermore, when
the shafts reach the 90.degree. perpendicular situation, they lock
and will not operate at all). We note that our measurement of angle
between output and input shaft is consonant with standard
mathematical practice. Namely, when the input and output shaft are
parallel in the `unbent` configuration, the angle between them is
180.degree.. As the output shaft is bent, this angle decreases
until reaching 90.degree. when the shafts are perpendicular, and
0.degree. when the output shaft is bent back upon the input
shaft.
[0160] Joints have been developed utilizing a floating intermediate
shaft and centering elements to maintain equal angles between the
driven and driving shafts, and the intermediate shaft. This
overcomes the problem of differential angles between the input and
output shafts.
[0161] The CV joint or constant velocity joint finds actual use in
automotive applications. As shown in FIG. 2 this is a joint
connecting the input axle 201 to the output axle 205. The splines
204 spin the spokes 209 which in turn spin the plurality of ball
bearings 202 on the inner ball race 203. These balls are confined
between the ball cage 206 and the outer socket 207, which has
depressions 210 into which the balls fit. Since the balls are
confined by both axles, they transfer the torque from the input
axle 201 to the output axle 205. An isometric view is given in FIG.
2b. The two main failures are wear and partial seizure. Furthermore
it will be appreciated that extreme angles between input and output
shafts of around 90 or less will not be capable of transferring
torque at all, and in practice a continuous angle of about
100.degree. degrees is the highest deviation from the straight
100.degree. configuration obtainable with a CV joint.
[0162] The double Cardan or double U-joint allows for a constant
velocity to be attained at the output shaft, unlike the single
U-joint. An improvement on this is two Cardan joints assembled
coaxially where the cruciform-equivalent members of each are
connected to one another by trunnions and bearings which are
constrained to continuously lie on the homokinetic plane of the
joint. This is the basis of US patent application 20060217206.
Therein is disclosed a constant velocity coupling and control
system therefore, the so-called `Thompson coupling`, as shown in
FIG. 3. A recent innovation, the Thompson coupling is a further
development of the double Cardan-joint, which doesn't rely on
friction or sliding elements (as the CV joint does) to maintain a
strict geometric relationship within the joint, and which is
capable of transmitting torque under axial and radial loads with
low frictional losses. This coupling has all loads carried by
roller bearings, with no sliding or skidding surfaces whatsoever.
It can tolerate axial and radial loads without degradation, with no
wearing components except replaceable bearings and trunnions, and
is less bulky than a double Cardan joint. However as will be
appreciated from FIG. 3, this is a rather complex affair.
Furthermore the maximum allowable angles are still restricted to a
small range around 180.degree., e.g. to an instantaneous minimum
allowable angle of 155.degree. and minimum continuous angle of
168.degree..
[0163] According to a preferred embodiment of the present
invention, a method is provided that allows the transfer of torque
from an input shaft to an output shaft, whose axis of rotation may
be varied continuously from nearly 0 degrees to nearly 360 degrees
with respect to the axis of rotation of the input shaft.
[0164] With reference to FIG. 4 a representative embodiment of the
invention is detailed. The input shaft 401 is rotated due to torque
from some external source. This torque is transmitted to spur gear
402. Spur gear 402 engages crown gear 403, which therefore rotates
and transmits torque to spur gear 404. It will be appreciated by
one skilled in the art that the spur and crown gears could be
replaced with bevel gears. This simple arrangement is well known in
the form of the bevel gear reversing mechanism. The key inventive
step of the present invention is to allow the output shaft 405 to
rotate not only about its own longitudinal axis but also about the
axis 406. This is accomplished in the embodiment shown by coupling
the output shaft 405 to axis 406 with a coupling that allows
relative rotation of the output shaft 405 around axis 406. It will
be appreciated that with this device, the output shaft 405 can be
rotated in nearly a full circle around the axis 406 with no
variation in the torque provided.
[0165] In FIG. 5 the same embodiment is shown in plan view. Torque
is transmitted from an external source to input shaft 401 and from
there to gearwheel 402. Gearwheel 402 engages crown gear 403, which
therefore rotates and applies torque to gearwheel 404. The output
shaft 405 is thus caused to rotate. The crux of the invention lies
in the extra degree of freedom allowed to the output shaft 405,
namely that it may also rotate about the axis of the crown gear
403, this being the key provision of the invention. Axis 406 is
preferentially but not necessarily largely collinear with the
rotational axis of the planetary gear 403. Since the sizes of the
gearwheels 402, 404 may be varied, the coupling as a whole can be
made to provide a gear reduction or enlargement, with
correspondingly greater or smaller output torque, and
correspondingly smaller or greater rate of angular rotation.
[0166] It should be noted that due to the symmetry of the device,
torque can also be transmitted in the opposite direction, from what
we have called the output shaft to what we have called the input
shaft. The terms `output` and `input` are therefore somewhat
misleading since either can be used for output or input.
Furthermore it will be appreciated that the change of the axis of
rotation of output with respect to input is a relative one, and
that therefore the input axis of rotation can be moved instead of
the output axis of rotation, or both may be allowed to rotate with
respect to a stationary coordinate system. This is more than simply
a matter of nomenclature; the effect can be used for instance to
transmit feedback. For example, an actuator can be used to move a
certain object, and a sensor can be attached to this object such
that the degree of movement achieved is transmitted back to the
operator of the device. A felicitous coaxial arrangement for such
an implementation requiring several simultaneous degrees of freedom
is described in the following.
[0167] It is within the scope of the invention to allow for
multiple coaxial input and output shafts to be employed
simultaneously. With reference to FIG. 6 an example of such an
embodiment is given in isometric view. The input shafts 611,612,613
are all collinear. They may be independent or dependent, as will be
determined by the configuration of keyways and shafts such as
617,618 that can couple two input shafts or two output shafts such
that they rotate together. The output shafts 614,615,616 are
rigidly coupled to output couplings 604,603,602 respectively and
therefore rotate with them. These output couplings are caused to
rotate by means of crown couplings 605,606,607 respectively. The
crown couplings are caused to rotate by means of input couplings
608,609,610 respectively. These input couplings are rigidly
attached to input shafts 611,612,613 and therefore rotate with
them. The key provision of the invention lies in the `extra` degree
of freedom available to the output shafts 614,615,616 which can
rotate along with output couplings 604,603,602 around the axis 620.
The axial support pin 601 fits into track 618 and travels with the
output shafts, supporting them against axial loading. The radial
support pin 621 supports the output shafts against radial
loading.
[0168] A further provision of the invention is for locking of
individual axes. In FIG. 6 one sees that bolts 622 have been
introduced which lock the outermost input shaft to the body of the
coupling. Therefore any attempt to rotate this input shaft will
result in a rotation of the entire coupling. Similar bolts can be
added to the output shafts as well, allowing the coupling to be
rotated around the axis of the output shaft. Finally, the crown
couplings 605,606,607 can also be locked to the base 623 of the
device. By so doing, the direction of the output shafts can be
changed, as can the disposition (in the sense of angular
orientation) of the entire joint itself.
[0169] It is within provision of the invention that the
aforementioned bolts be replaced with coupling elements such as
linear actuators, electromagnets, and the like. It will be obvious
to one skilled in the art that such coupling elements can be so
constructed that they couple or decouple electronically, allowing a
further level of control over the device.
[0170] In FIG. 7 one sees and alternative embodiment of the device
with modified mechanical dimensions. In this figure the modularity
of the coupling is evident; the output shafts have been removed
from the device and can now be replaced by a different output shaft
(suitable for a different surgery, for instance). The output shaft
(not seen) attaches to the output flange 701.
[0171] A similar embodiment is shown in FIG. 8, where both input
and output shafts have been removed. This would allow (for
instance) the coupling as a whole to be cleaned.
[0172] In FIG. 9a,b isometric views of an embodiment of the joint
are shown. A gear lock bar 910 is seen. This gear lock bar serves
to lock certain gears of the device in place, in place of the bolt
622 of FIG. 6. The gear lock bar allows (for example) a surgeon to
lock the output shaft into a desired direction.
[0173] In FIG. 10 an exploded view of the joint of a joint of the
device of the current invention is shown. Input concentric
cylinders 902 attach to the input flange 903. This flange is
rigidly coupled to coupling orientation gears 904, 905. Bolts 906
can be used to couple the flange to a rigid surface. The input
bevel gears 907 communicate torque to the crown gears 909, which in
turn communicate this torque to the output bevel gears 911. These
output bevel gears 911 are in communication with the output
concentric cylinders 913. Bearing/stay 908 keep the crown gears 909
in place. The gear lock 910 allows the angle of the output shaft
with respect to the input shaft to be locked. It should be
emphasized that the input and output shafts 902, 913 can be
detached from their respective flanges (902,912) if necessary,
allowing different sections of the device to be removed or
replaced.
[0174] In FIG. 11a the gear lock release is seen; a button 950 is
depressed to release the gear lock and allow the output shaft 952
to be rotated with respect to the input shaft 951. In FIG. 11b
another view is given allowing one to note the large angular range
of the output shaft, moving from position 952a to position
952b.
[0175] In FIG. 12a-d the shaft lock is shown in greater detail. The
shaft lock 910 can either allow or disallow free rotation of the
shaft gear 905, thereby allowing or disallowing repositioning of
output axis with respect to the input axis.
[0176] It will be noted by the astute observer that the output axis
of rotation of the instant invention can rotate in a single plane
only if one does not use the aforementioned provision of bolts or
output shaft lock(s) to allow for rotation of the coupling
mechanism itself. However as will be clear to one versed in the
art, this restriction can be removed by the simple expedient of
providing one or more further identical joints of the instant
invention in series with the first, as shown in FIG. 13, where
three joints 801,802,803 have been coupled in series. An embodiment
with two or more joints in series provides a nearly full range of
motion of the output shaft, in all directions relative to the input
shaft. The only restriction on the angles is that the various
shafts cannot physically overlap any other shaft, thus eliminating
certain configurations from the realm of possibility. It will be
appreciated however that the disallowed positions form a small
proportion of the total universe of possibilities. This is
especially relevant when considering that the possible input-output
angles of e.g. single or double Cardan joints are restricted to
small angles of around 168 degrees or less.
[0177] It will be appreciated that the gear ratio between input and
output shafts can be varied by variation of the size of the wheels
or gearwheels of the couplings. In particular, if the input and
output gearwheels have radii r.sub.1, r.sub.3 then the total gear
ratio will be r.sub.1/r.sub.3.
[0178] The constant velocity joint of the instant invention
comprises: [0179] i. An input shaft adapted to be rotated around an
input axis of rotation (the longitudinal axis of the shaft) by a
sources of torque. [0180] ii. An input transmission means, coupled
to one of said input shaft, said input transmission means defining
a first plane substantially perpendicular to said input axis of
rotation. The input transmission means may for instance be a spur
gear. [0181] iii. A second transmission means rotatably connected
to said input transmission means;
[0182] said second transmission means defining a second plane, such
that said second plane is substantially perpendicular to said first
plane. The second transmission means may comprise for instance a
crown gear meshing with the first spur gear. [0183] iv. An output
transmission means rotatably connected to said second transmission
means;
[0184] said output transmission means defining a third plane; said
third plane being substantially perpendicular to said second plane.
The output transmission means may comprise for instance a spur gear
meshing with the second transmission crown gear. [0185] v. An
output shaft, coupled to said output transmission means, adapted to
rotate around an output axis of rotation, said axis of rotation
being free itself to rotate.
[0186] It will be noted that the angle between said first input
axis of rotation and said final output axis of rotation may vary in
an angular range of about 0 to about 360 degrees.
[0187] The transmission means may be selected from a group
consisting of gearwheels, wheels, crown gears, bevel gears, or
other means for transmitting rotational motion, or combinations
thereof.
[0188] In one embodiment of the invention an axial support member
(601) is provided, to provide axial support to the output shafts.
Also a circular track (618) centered on the axis of rotation of
said second transmission means is provided, said axial support
member being adapted to fit into said track and slide within
it.
[0189] In one embodiment of the invention a radial support member
(604) is further provided to provide radial support to the output
shaft, said radial support member being adapted to rotate in said
second plane.
[0190] In one embodiment of the invention several coaxial input
shafts are coupled individually to several coaxial output shafts,
allowing independent transmission of torque from input to output on
several shafts simultaneously.
[0191] It should be appreciated that the output shafts may be
coupled to a wide variety of devices, such as graspers, cutters,
splicers, welders, force-feedback devices, robotic hands, and the
like. In particular the use of force-feedback devices to provide a
`return signal` by means of one or more shafts will be found
especially useful in microsurgery, robotics, and the like wherein
it is desirable to have some feedback concerning the `feel` of the
work being done.
[0192] It should be pointed out that amongst other advantages of
the instant invention is the fact that the torque-providing
elements that turn the input shafts may be located rather distant
from the location where the torque is applied. This is especially
important in such fields as arthroscopy, microsurgery, and
robotics, wherein it is generally desirable that the point at which
delicate operations occur are as compact as possible. Also the
presence of motors on or near joints can cause unwanted extra
weight, moments of inertia, and the like. The instant invention
allows many sources of torque to be transmitted in parallel in a
minimum of space limited only by the shaft wall thicknesses, and at
a distance from the actual operations of the output shafts that is
in principle unlimited. No motors are required at the location of
the joint itself, as in many current applications.
[0193] It should be further appreciated that the instant invention
allows for the actuating motors to be located in a central
protected location such as the abdomen of a robot, the center
portion of a tank, etc. This further allows for a single motor to
activate several input shafts independently. If for example it is
discovered that in a particular application certain actions
requiring rotation of shaft A preclude other actions requiring
rotation of shaft B, a single motor can be used to provide the
torque necessary for these actions, and switched from input shaft A
to input shaft B by a suitable gearbox as will be obvious to one
skilled in the art.
[0194] In one embodiment of the invention access is given to the
crown gears of the device, in effect changing the device into a
three-terminal or `T` or `Y` device. In particular the central or
crown gears 605, 606, 607 (FIG. 6) may be connected to input/output
shafts of their own. Now more complex operations may be allowed,
wherein further couplings are connected to this center shaft, or
further torque sources, or further output devices such as graspers,
cutters, and the like, or sensors.
[0195] We now turn to the incorporation of this coupling device
into a laparoscopic instrument of improved design. In the prior art
one finds a large number of laparoscopic positioning systems such
as those shown in FIG. 14. These will in general allow a small
number of degrees of freedom, the maximum found in a search of the
patent literature being five degrees of freedom.
[0196] To improve upon this situation while keeping the simple
tubular design of the laparoscope intact, we incorporate the
aforementioned coupling device into an endoscope/laparoscope
maneuvering system as shown in FIG. 15a,b.
[0197] The cylindrical members (consecutive arm sections) 995, 996,
997 and 998 contain a plurality of concentric cylinders, each able
to rotate independently and thereby activate an independent degree
of freedom. By means of these concentric cylindrical members, the
couplings (i.e., the constant velocity couplers) 1002, 1003, 1004,
1005 and 1006 serve to rotate/translate the device (namely the
endoscope/laparoscope 1001b or the camera 1001a) in the directions
DOF.sub.1 (1007), DOF.sub.2 (1008), DOF.sub.3 (1009), DOF.sub.4
(1010), DOF.sub.5 (1011), DOF.sub.6 (1012) and DOF.sub.7 (1013), in
which DOF.sub.1 represents the ability of the system to move the
endoscope or laparoscope forward and backwards in direction
represented by numerical reference 1007, DOF.sub.2 represents the
ability of the system to move the endoscope or laparoscope in a
zoom movement i.e. in and out of the patient body through the
penetration point (represented by numerical reference 1008),
DOF.sub.3 represents the ability of the system to move the
endoscope or laparoscope to the right and left in direction
represented by numerical reference 1009, DOF.sub.4 represents the
ability of the system to fine tune the endoscope or laparoscope
movements to the right and to the left in direction represented by
numerical reference 1010, DOF.sub.5 represents the ability of the
system to fine tune the endoscope or laparoscope movements forward
and backwards in direction represented by numerical reference 1011,
DOF.sub.6 represents the ability of the system to rotate the camera
1001b with respect to the endoscope's 1001a long axis. This degree
of freedom is necessary to keep the horizon of the image when using
endoscope with "angled edge," and DOF.sub.7 represents the ability
of the robot to rotate the endoscope 1001b about its long axis.
[0198] Views of the same device from the opposite direction are
shown in FIGS. 16a,b. Isometric views are shown in FIGS. 17a,b.
Further side views are shown in FIG. 18a,b with a pencil included
for scale.
[0199] FIG. 19 shows the main and the preferred embodiment of the
present invention which incorporates the positioning elements of
FIGS. 15-18 upon a standardized tubular arm 1901. As described
above, the core concept of the present invention lies in the fact
that the positioning section 1902 may be removed entirely from the
fixed section (tubular arm) 1901 e.g. for replacement, repair,
cleaning, etc.
[0200] In FIG. 20 illustrates a more complete embodiment, where two
consecutive tubular members 1901, 1902 are employed. The lower
tubular member 1902 may for instance be fixed to the floor,
ceiling, surgical table, or the like. This tubular member is in
certain embodiments endowed with one or more cylindrical motors
(which will be further explained in FIG. 22) within the body of the
cylinder, adapted to turn a set of the concentric
torque-transmitting elements described above.
[0201] The second tubular member 1901 transmits these torques to
the medical tool to which he is coupled. It is within provision of
the invention that one of these multiple torques can be used to
rotate the upper tubular member 1901 about the coupling element
2004. It is also within provision of the invention that these two
arms may be detached from one another. The upper tubular member
1901 may also be provided with one or more internal cylindrical
members such as shafts or motors to power the various operations of
the laparoscope, including the various possible movements of the
laparoscope positioning section 2003, and any surgical instruments
attached to the end of the laparoscope tube 2005.
[0202] It is emphasized that the number of the consecutive tubular
members is not limited to two.
[0203] In FIG. 21 a cross section of the tubular sections shown in
FIG. 20 is shown. In the cross section of FIG. 21 one can see the
two motors 2101, 2102 of the lower arm and the two motors 2103,
2104 of the upper arm. Each of the motors is adapted to provide
movement in a specific direction. For example, motor 2104 may be
adapted to provide left and right movement; motor 2103 may be
adapted to provide forward and backwards movement; motor 2102 may
be adapted to provide zoom in and zoom out movements; and, motor
2101 may be adapted to provide rotational movements.
[0204] In FIG. 22 an embodiment of the device is shown in use. The
lower arm 2201 is shown fixed to the operating table 2202. The
upper arm 2203 may rotate about the coupler between the upper and
lower arms, while the seven degrees of freedom of the laparoscope
positioning section 2204 allow the laparoscope 2205 to be moved
controllably in many ways, as may be required during surgical
procedures.
[0205] In actual use such a laparoscope as described above may be
operated either manually by a human being, or robotically,
according to a programmed set of instructions, by a robotic
mechanism obeying human commands, remotely, or the like.
[0206] A robotic mechanism is shown in FIG. 23a,b, In FIG. 23a,b,
various possible motions of the device are illustrated.
[0207] In FIGS. 24a and 24b various possibilities for operation of
the device are shown. In FIG. 24a a surgeon is shown operating
using the device. As will be obvious to one skilled in the art the
actuation may be carried out using a variety of means such as
joystick control, keyboard control, voice control, manual control,
power-assisted control, or the like. In FIG. 24b the device is
shown without a surgeon, who may in principle control the movements
of the device remotely, or in principle the device may be operated
entirely algorithmically.
[0208] It is within the scope of the invention that the base and
body units of the invention provide various desirable elements to
allow complex surgical procedures to be carried out, such as one or
more fluid channels, one or more electrical conductors, one or more
fiber optic channels, and the like. The fluid channels may provide
e.g. CO.sub.2 for inflating a body cavity, saline solution for
flushing, vacuum for aspirating blood, pus, or other bodily fluids,
and the like. The electrical conductors may conduct voltages to
operate various motors or actuators, conduct information from
sensors such as video cameras or piezoelectric gauges, and the
like. The fiber optic channels may conduct visual information from
the body or may provide light within the body cavity. It is within
provision of the invention that these various elements be conducted
in tubes threaded within the tubular structures of the current
invention, or attached to the outsides thereof.
[0209] One skilled in the art will realize that the device
described above has the potential to facilitate surgery by freeing
one hand of the surgeon that would otherwise have to grip the
laparoscope.
[0210] It is further within the scope of the present invention to
provide a two-part robotic laparoscopic device useful for
functional endoscopic sinus surgery (FESS). If the nasal sinuses
become blocked for example by nasal polyps, growths, allergies or
infection, causing great discomfort. The first line of treatment
for sinus blockages is medical therapy, however in some cases this
is unsuccessful and surgery is required. Sinus blockages are a
common problem and sinus surgery is one of the most frequently
performed, failure to treat sinus blockages can result in facial
pain, headaches and rarely, complications. Reference is now made to
FIGS. 36a-c, 37 and 41, illustrating several embodiments of sinus
surgery. FESS, allows the procedure to be performed as day
operation, accessing the sinuses by inserting an endoscope through
the nose and removing blockages in a relatively non-invasive
manner, resulting in easier and quicker recovery and lower risks
than traditional sinus surgery. Thus FESS is a precise, minimally
invasive way to open your sinuses and treat chronic sinus
infections. The present invention is provided to enable access of
all areas of the sinus and naval cavity with the endoscope,
ensuring better treatment of the blockages.
[0211] As described above, according to another embodiment of the
present invention to improve upon the interface between surgeon and
automated assistants by communicating the surgeon's current
instrument of choice, supplying location data to the image
processing computing software thereby directing the endoscope to
focus on said choice. The technology relies on marrying a
conventional laparoscopic system with data obtained from small RF
transmitters attached to a surgical tool.
[0212] The present invention provides an interface between a
surgeon and an automated assistant, comprising (a) at least one
array comprising N RF transmitters, where N is a positive integer;
(b) one RF receiver, said receiver provided with at least one
directional antenna; (c) means for attaching said RF transmitter
array to at least one surgical tool; and, (d) a computerized
operating system adapted to record the relative signal strength
received by said RF, receiver and to calculate therefrom the
position of each of said N RF transmitters, and further adapted to
provide automatically the results of said calculation to the human
operator of said interface. It is within the essence of the
invention wherein said computerized operating system calculates at
least one of the parameters chosen from the group consisting of (a)
the spatial location of said at least one surgical tool; (b) the
path of said at least one surgical tool; (c) the spatial location
of the point of insertion of said at least one surgical tool into
the body of a patient; (d) the spatial location of the tip of said
at least one surgical tool; (e) matching each RF transmitter code
with each calculated spatial location of said at least one surgical
tool and/or said tip of said at least one surgical tool, and
further wherein said computerized operating system provides
automatically the results of said calculation to the human operator
of said interface.
[0213] In one of the preferred embodiments of the invention, any
desired surgical instrument is fitted with an RF transmitter, and
selection is achieved by depressing its button.
[0214] The invention discloses two methods of operation: a manual
method, in which a transmitter emits an RF signal only when the
surgeon presses a button located e.g., on one of the arms (either
left or right--but not both simultaneously), the system then
indicating the direction of that arm, and an automatic method, in
which all transmitters continuously emit RF signals and the system
tracks the direction of all transmitters simultaneously. When the
surgeon presses a button of one of the transmitters, the system
output is the direction and location of the specific
transmitter.
[0215] The automatic mode has some advantages over the manual mode
because the system can make use of history track files in order to
filter the data and apply prediction algorithms. The continuous
stream of data also allows the software to compute additional
important data such as the insertion point of each tool, and the
predicted tools location on the image.
[0216] System operation will be explained for both MANUAL
(sequential), and AUTOMATIC (periodic or simultaneous) modes. In
order to simplify the explanation a system used to locate the
positions and directions of only 2 surgical tools is described, but
the method described can be used with minor changes to locate the
position of any number of surgical tools used in any laparoscopic
surgeries.
[0217] Reference is now made to FIG. 25a which schematically
describes the surgical tool positioning MANUAL system according to
one embodiment of the invention. An antenna 31 is set and a
receiver is preferably mounted on, or near, the robotic camera
holder. Two identical transmitters, i.e., (i) transmitter 11
mounted on surgical tool 10; and (ii), transmitter 21 mounted on
surgical tool 20 are provided. A control and processing function
controller 40 is further provided, being either a laptop PC or an
embedded controller.
[0218] As described above, in the MANUAL system the transmitter
emits RF signal only when the surgeon presses upon the surgical
instrument the surgeon desires to track. Once the transmitter
transmits a signal, the receiver communicates with the controller
and instructs the tracking of the medical instrument desired by the
surgeon.
[0219] Reference is now made to FIG. 25b which schematically
describes the surgical tools positioning AUTOMATIC system according
to yet another embodiment of the invention.
[0220] As described above, in the AUTOMATIC system the transmitter
continuously emits RF signals. Therefore, the receiver constantly
communicates with the controller.
[0221] The transmitters 11 and 21 can operate in one of three
modes: (a) sequential/manual mode, as shown in FIG. 26a, upon the
surgeon's pressing an appropriate button (manual mode); (b)
periodic/automatic mode as shown in FIG. 26b, in which the
transmitters attached to the two tools provide pulsed signals at
different pulse rates; or (c) simultaneous/automatic mode, as shown
in FIG. 26c, in which the two transmitters transmit simultaneously
and continuously, but at different radio frequencies. In all three
modes, the receiver can detect and process individual reception
from any one of the two tools and identify which transmission
belongs to which tool.
[0222] Reference is now made to FIGS. 27a,b, 28a through 28d, and
29, in which further details of the system operation are
illustrated. The receiver receives sequentially the signal of each
tool through the antenna set, the antenna set comprising at least
one (preferably) multiple directional antennas array as shown in
FIG. 31a, where at least one of the antenna is connected to the
receiver. In order to locate the transmitter, at least two
directional patterns are required as illustrated in FIG. 32a. The
figure illustrates a typical antenna's pattern as a function of the
signal's angle and of the intensity.
[0223] Alternatively, the transmitted signal may be modulated (in
different embodiments of the invention, either (a) frequency
modulation or (b) amplitude modulation or (c) both FM and AM
simultaneously). Thus, in order to identify the arm from which the
transmission is being received, each transmitter has a different
modulation frequency. Hence an easier detection of the arm is
enabled. In general once the correct transmitter has been
identified, the following mathematical analysis is performed:
[0224] The direction of each transmitter (and hence the desired
instrument) is calculated by using a single receiver having at
least 3 directional antennas. [0225] The received signal strength
(RSS) is a function of the distance (d) between the receiver and
the transmitter (i.e., the instrument); the strength of the
transmitted signal (P); the path loss exponent (n); and the
antenna's gain (Gr). [0226] Since all the antennae are co-located,
the ratio of the RSS will be the ratio between the antennas'
gain.
[0227] Therefore, by knowing how the gain ratio varies with the
angle--one can calculate the angle from which the signal has been
transmitted.
[0228] The above mentioned mathematical analysis id performed based
on the following facts:
[0229] The method uses several directional antenna that are
co-located as a set of receiving antenna; and the transmitter is
assumed to be located somewhere around the receiving antenna
set.
[0230] As described, the method is adapted to find only the
direction of the transmit antenna by comparing the received power
from all antenna in the set. As commonly known, the received power
depend on the transmit power (PT), the distance from receiving to
transmit antenna (d) and on the receiving antenna gain (Gr(i)) in
the direction of the transmitter. Since the set of antenna are
co-located (the transmit power (PT), the distance from receiving to
transmit antenna (d) et cetera are eliminated) and the ratio of the
receiving signal strength (RSS) is as follows:
RSS(antenna(i))-RSS(antenna(k))=G.sub.r(antenna(i))-G.sub.r(antenna(k))
[0231] As can be seen, the difference in the RSS does not depend
upon the transmit power PT (since the PT received by each antenna
is the same), and it does not depend upon the distance (since the
received antenna are co-located).
[0232] From the difference set of RSS, the difference in the gain
between the receiving antennas is known.
[0233] Since the receiving antennas are directional, the gain
pattern is dependent only upon the angular positioning of the
transmitter (and hence the instrument). Therefore, the angular
position and hence the direction can be resolved unambiguously from
the gain difference, and it is therefore possible to calculated the
angle from which the signal has been transmitted from a measurement
of how the gain ratio varies with the angle (see FIG. 27b). As
illustrated in FIG. 27b, once the RSS difference is known, the
angle from which the signal is being sent (i.e., the angular
location of the transmitter and hence the instrument) can be
calculated.
[0234] It should be noted that the above mentioned calculation is
much less sensitive to multipath environment found whilst applying
the methods in laparoscopic surgeries.
[0235] According to another embodiment of the invention, the
antenna array has more than two patterns, allowing the system to
identify the direction of the tool with a finer resolution.
Reference is now made to FIG. 31b, in which a non-limiting example
of an additional embodiment is illustrated, in which the antenna
array comprises four directional patterns: left, right, forward and
aft. From the direction from which the strongest reception is
received, the system is able to identify the sector in space in
which the tool is located. Moreover, from interpolation of the
received power from all antenna patterns, even finer directional
resolution is possible.
[0236] The receiver detects the received signal power for each
antenna in the array and reports it to the controller. The
controller then resolves the directions of the two tools relative
to antenna 31. Transmitters and 21 shown in FIG. 28a may transmit
in a wide range of frequencies; a typical frequency is the ISM band
of 430 MHz. Transmission is done at very low power, generally below
about 1 mW. The transmitted signal is modulated (in different
embodiments of the invention, either (a) frequency modulation or
(b) amplitude modulation or (c) both FM and AM simultaneously). In
a preferred embodiment, the modulation is performed at an audio
rate of about 1.5 kHz. The transmitter uses a built-in antenna. In
order to identify the arm from which the transmission is being
received, each transmitter has a different modulation frequency. In
a preferred embodiment of the invention, the frequencies are
located within the band encompassing the range of from about 1.0
kHz to about 1.5 kHz.
[0237] The signal for each transmitter is received by all antennas
in the array (see FIG. 28b above). The antennas in the array
typically comprise three very short dipoles mounted on the edge of
an equal edge three-legged star or circle, as shown in FIGS. 31a
and 31b. The diameter of the circle or three-legged star is about 8
to 12 cm for operation at about 430 MHz. The use of the antenna
array to identify the beam pattern is illustrated schematically in
FIG. 28b. The antenna pattern is formed by combining the signal
received by each antenna with different delays and signal weights.
In order to set the pattern, in a typical embodiment, each antenna
output is split into several equal power signals and a sample of
each antenna signal is combined into one directional output. Which
output is being measured is selected by an external switch.
[0238] The receiver receives the signal in sequence from each
directional pattern and detects the signal power in any pattern for
the signals from both tools; from the power ratio the signal
direction is calculated. For example, for a two pattern antenna
(left and right) if the signal from left antenna is much stronger
than from right one, then the signal must have arrived from the
left and vice versa. In parallel, the signal modulation as
transmitted is detected and the modulation frequency is measured.
Since each transmitter has a different modulation frequency,
identification of the transmitter from which a particular signal
originates is straightforward.
[0239] The receiver may be of any type, but in order to reduce the
cost, size and power consumption, in a preferred embodiment, the
receiver is a single conversion receiver that converts the input
signal to base band. The receiver block diagram is shown in FIG.
28c. The receiver operation is as follows: the RF input is filtered
around the transmitter frequency band then passed through a
variable attenuator controlled by the system controller. Next, it
is then amplified and then down converted using a Quadrate mixer
and a local oscillator. The mixer outputs are the IF baseband: I
(in phase) and Q (Quadrate) outputs, which are filtered by two low
pass filters (e.g., about 30 kHz) then amplified. The base band
signal powers are then detected. The DC power relative to the
signal power is selected in sequence. The analog signal is then
passed to an analog to digital converter (ADC), following which the
total received power is computed digitally.
[0240] In an additional embodiment of the invention (not
illustrated), the base band signal is analog to digital converted,
so that the power of both the I and the Q channel is converted to a
digital value. The local oscillator frequency is locked by the PLL
to the XTAL reference oscillator, controlled by the system
controller. In order to ensure that received signal is within a
limited range the receiver gain is adjusted automatically (AGC).
Finally, as shown in FIG. 28d, the digital signal power is
transferred to the system controller, where the controller
calculates from the time of reception from which tool it is
received and from which antenna pattern, using the power the
controller compute the tool direction for each of the two
tools.
[0241] The controller includes a timer based sequencer, preferably
built into the microprocessor timing unit, that switches the
receiver antenna, and in case of multiple frequency transmission,
sets the receiver frequency sequentially. The operation sequence of
the system is illustrated schematically in FIG. 29, which shows the
system control software operation flow:
[0242] [1] The AD signal is averaged to detect the average
amplitude, averaging being done over one dwell duration ("X"
indicates the output after averaging);
[0243] [2] Signal presence is detected when X is above a
predetermined threshold;
[0244] [3] Average amplitude X is saved in a vector array (Aver_A
(n), n={1,2, . . . N)) if signal is present, the storage being done
on the appropriate antenna number place in the array;
[0245] [4] If for a given antenna, signal is present on N
successive dwell durations, the signal direction is calculated;
[0246] [5] The modulation (in the particular embodiment
illustrated, AM) is detected from the signal power input;
[0247] [6] The modulation frequency is measured; and,
[0248] [7] From the measured frequency, the arm type, is detected;
in the case of weak signal or simultaneous transmission, the module
reports "can't decide," indicating a garbage signal.
[0249] In embodiments in which the transmitter operates
periodically, both transmitters operate for a fraction of the time
then switch off, then switch on again and so on with a constant or
random cycle periodicity, each transmitter transmitting with a
different transmission pulse cycle time in order to ensure that
transmissions will not overlap at all times but only at times
separated by t.sub.1t.sub.2, where t.sub.1 and t.sub.2 are the
pulse cycle times of the two transmitters. In parallel, the
receiver sequentially switches the receiver channel among the
different antennas and dwells on each antenna for a fixed dwell
time. From the level of signal received, the system determines
whether or not a signal is present. If a single signal is present
either from the right arm or left arm transmitter, the direction of
the signal is calculated from the signal strength received from
different antennas, and the arm is identified from the internal
modulation frequency. In case of coincident simultaneous transmit
the receiver cannot identify the signal modulation therefore the
measurement is rejected. In an additional embodiment, the system
tracks the transmission period cycle of each arm and predicts the
simultaneous transmission times in order better to identify which
arm's signal is being detected.
[0250] In order to ensure that the direction of a single
transmission can be calculated (if only a single transmission is
received), the "transmit on" duration is at least (N+1) X dwell
intervals, where N is the number of antenna outputs. This ensures
that the transmission is received during at least N successive
dwell times, allowing the system to calculate its direction. For
example if the receiver antenna is switched in sequence staying on
for 10 ms (i.e., a 10 ms antenna dwell time) in each pattern out of
two patterns, then the total antenna switch time cycle is 20 ms,
and the transmitter switch on time is required to last for at least
30 msec. For example, in one embodiment of the invention, the
transmit on/off cycle times are 120 ms and 150 ms for the left and
right arm transmitter respectively. Each transmitter is on for 30
ms and off for the rest of the time The antenna switch versus
transmit periodic operation is shown in FIG. 30a.
[0251] In the case of sequential transmission, each transmitter
should be on for at least (N+1) X dwell intervals (receiver antenna
dwell time). The antenna switch versus transmit sequential
operation is shown in FIG. 30b.
[0252] In embodiments in which the two transmitters operate at
different frequencies, the receiver scans all antenna patterns at
the first frequency, then switches to the second frequency and
scans all antenna patterns again, then returns to the first
frequency, and so on.
[0253] Reference is now made to FIG. 31a, which illustrates an
embodiment of the invention in which the directional antenna array
has a planar structure. The short dipoles at each segment 72a,b,c
are covered to protect the wires and the circuits from humidity and
mechanical fractures. The arms 73a,b,c are made of any appropriate
flexible material.
[0254] Reference is now made to FIG. 31b, which illustrates an
embodiment of the invention in which the directional antenna array
has a non-planar spatial structure. The fourth short dipole at
segment 72d is not located in the plane that contains segments
72a,b,c. This arrangement allows the system to compute the spatial
direction of the RF transmitter.
[0255] Reference is now made to FIG. 31c, which shows the antenna
located on an automated automated assistant maneuvering system
according to one embodiment of the invention.
[0256] Reference is now made to FIGS. 32a,b,c, which illustrate in
a non-limiting manner some types of surgeries in which the location
system disclosed in the present invention can be utilized.
[0257] FIG. 32a shows an example of using the location system in
abdominal laparoscopic surgery.
[0258] FIG. 32b shows an example of using the location system in
knee endoscopic surgery.
[0259] In FIG. 33a-c another aspect of the invention is shown
particularly suited for sinus surgery.
[0260] Reference is now made to FIG. 34, which illustrates an
additional embodiment 420 of the invention herein disclosed.
Surgical device 4201 is held in position by robot end effector,
which comprises a plurality of shaft tubes 4204 (in the embodiment
illustrated, there are 5 shaft tubes 4204a-4204e) connected in
series by a set of joints 4205. One of said joints (in the
embodiment shown, 4205a) connects the first shaft tube 4204a to the
body of the instrument, while another (in the embodiment shown,
4206) is attached the final shaft tube (in the embodiment shown,
4204e) and comprises means (e.g. a closeable slot or hole) to hold
the surgical device in a position fixed relative to the final shaft
tube. Motor means for effecting movement of the shaft tubes is
contained within motor box 4202, and the controller mechanisms are
contained with controller box 4203.
[0261] Reference is now made to FIG. 35, which illustrates the
various DOF and an external view of the means for connecting
medical device 4300 to the control unit according to an embodiment
430 of the invention. According to this embodiment, 6 independent
DOF are available to the medical device (FIG. 35a): (1) rotation
4311 of the entire connecting means about the z-axis; (2)
translation 4312 of the medical device along a predetermined axis
within the x-y plane; (3) rotation 4313 of the medical device about
the axis defined by 4312; (4) rotation 4314 of the medical device
about an axis perpendicular to that defined by 4312; (5) rotation
4315 of the medical device about the z-axis; and (6) translation
4316 of the instrument along the z-axis. Motion about DOF 4312-4316
is accomplished without gross movement of the entire connecting
means. As described in detail below, independent motions along
these DOF are enabled by a system of n joints 4301 (in the
embodiment shown, n=3; in other embodiments, n may be any positive
integer) terminating in end joint 4303 and connected by a series of
n shafts 4302. As illustrated in FIGS. 35b, 4311 and 4312 can be
considered a vector in the x-y plane and an angle in the x-y plane
relative to the x-axis, respectively. Thus, 4311 and 4312 define
the location of a point in space through which the longitudinal
axis of the medical device (which is located parallel to the
z-axis) passes. This point in space can be thought of alternatively
as the center of a bead 4320 through which the medical device
passes. As shown in FIG. 35c, rotations 4313 and 4314 can be
considered rotations of the bead about two mutually perpendicular
axes in the x-y plane. FIG. 35d illustrates how translation 4315
and rotation 4316 are defined relative to the point 4320.
[0262] Reference is now made to FIG. 36, which illustrates means by
which motion about DOF 4311 are accomplished according to one
embodiment of the invention. Rotation is possible through any
arbitrary angle 4311 about rotation axis 4311x, as illustrated
schematically in FIG. 36a. The motions are enabled by a system of
gears, as illustrated schematically in FIG. 36b. The first gear
4330 is mated to input shaft 4302i. Intermediate gear 4331 is mated
to first gear 4330 and which in turn mated to a second gear 4332
that is rigidly connected to one end of output shaft 4302o and
rotates around an axis substantially coincident with the
longitudinal axis of the output shaft. A plurality of bolts 4333
fix output shaft 4302o to joint 4301a.
[0263] Reference is now made to FIG. 37, which illustrates means
for enabling motion about DOF 4312 and 4313. Illustrated in FIG.
37a is shaft 4302a, which connects joints 4301a and 4301b. Also
illustrated is internal tube 4313a which contacts shaft 4302a via
bearing 4313c. As illustrated in FIG. 37b, this bearing allows
joint 4301a to rotate freely about the longitudinal axis of
external tube 4313b (see FIG. 38). Disposed about at least part of
the outer surface of tube 4313a is a threaded portion 4312b, while
a threaded portion 4312a is disposed about at least part of the
inner surface of shaft 4302a; the two threaded regions are in
contact such that controlled rotational motion of 4302a relative to
4313a is possible. The threaded regions are shown in more detail in
FIG. 37c. When output gear 4332, which is rigidly connected to one
end of tube 4313a, rotates, threaded portion 4312a necessarily
rotates as well. A plurality of protrusions 4312c disposed about
the outer surface of tube 4313a and substantially parallel to its
longitudinal axis fit into matching grooves 4312d disposed about
the inner surface of shaft 4301a (the protrusions and grooves are
shown in detail in FIGS. 37d and 37e). Because of this
protrusion/slot interface, rotation of output gear 4340 cannot lead
to rotation of tube 4301a.
[0264] Reference is now made to FIG. 38, which illustrates means
for enabling motion about rotational DOF 4313 and the spatial
relationships between the components responsible for this motion
and those responsible for independent motion about DOF 4312. Once
again, the portion connecting joints 4301a and 4301b is
illustrated. Output gear 4350 is rigidly connected to one end of
external tube 4313b (FIG. 38a) and rotates about an axis
substantially coincident with the longitudinal axis of the tube. As
illustrated in FIG. 38b, tubes 4313a and 4313b are located within
shaft 4302a, with longitudinal axes substantially coincident. FIGS.
38c and 38d illustrate translation along 4312 and the consequent
motions of tubes 4313a and 4313b. As illustrated in FIG. 38e, the
outer surface of internal tube 4313a and inner surface of external
tube 4313b are not circular, but are rather designed to prevent
free rotation of the inner tube with respect to the outer tube. In
a preferred embodiment, the outer surface of inner tube 4313a has a
substantially polygonal cross-section, and the inner surface of
outer tube 4313b is machined substantially to match the shape of
4313a. In a more preferred embodiment, the substantially polygonal
cross-section is substantially hexagonal. Other shapes are
possible, e.g. facing off a portion of a substantially circular
cross-section to provide a single planar surface, with the planar
surfaces of the inner and outer tubes corresponding to prevent the
possibility of free rotation of the inner tube. By this means,
rotation of 4313b through an angle .theta. necessarily leads to
rotation of 4313a through the same angle. As illustrated in the
figure, rotation through any arbitrary angle .theta. is possible
for any value of the translational extension 4312.
[0265] Reference is now made to FIG. 39, which illustrates the
relative motions of DOF 4313-4316. As shown in FIG. 39a, all of the
axes of rotation of the distal link meet at point 4320. The
rotation axes relative to the long axis of medical device 4300 are
illustrated in FIG. 39b.
[0266] Reference is now made to FIG. 40, which illustrates means
for enabling independent motion about DOF 4314. Input gear 4314b is
rigidly connected to one end of internal tube 4314a, with its axis
of rotation substantially coincident with the longitudinal axis of
4314a. Input gear 4314b is mated to intermediate bevel gear 4314c,
which in general is not in the same plane. In the preferred
embodiment illustrated in the figure, the two gears rotate about
axes that are substantially perpendicular. Intermediate spur gear
4314d is substantially rigidly connected to, and rotates about
substantially the same axis as, 4314c, although, as illustrated in
the figure, the ratio between the two gears is not necessarily
equal to 1. Intermediate spur gear 4314d is mated to distal link
4314e via interaction with a toothed portion of said distal link.
Thus, rotation of internal tube 4314a causes rotation of input gear
4314b, leading to rotation of intermediate bevel gear 4314c and
hence rotation of intermediate spur gear 4314d, causing rotation of
distal link 4314e.
[0267] Reference is now made to FIG. 41, which presents a general
illustration of means for effecting motion about DOF 4315 and 4316.
The motions relative to the connection means are shown in FIG. 41a,
and the means for effecting motion of the medical device are
illustrated in FIG. 41b. Means for effecting motion about DOF 4315
comprise worm drive 4315a and worm gear 4315b. As illustrated in
FIG. 41c, worm gear 4315b is substantially ring-like in design,
with the gear teeth disposed about the outer circumference of the
ring. The inner circumference of the ring comprises a protrusion
that is adapted to fit into a matching slot in the outer
circumference of, and substantially parallel to the longitudinal
axis of, rack 4316a. Rack 4316a is adapted to hold medical device
4300. Means for effecting such holding are well known in the art;
as a non-limiting example, rack 4316a may comprise a bore along its
longitudinal axis, wherein said bore is of the proper diameter
(possibly with stopping down) to provide a snug fit to medical
device 4300. Rotation of worm drive 4315a about its axis leads to
rotation of worm gear 4315b about its longitudinal axis, causing
rotation of rack 4316a about its longitudinal axis, and thus
causing medical device 4300 within to rotate in proportion to the
amount of rotation of the worm drive. Translational motion about
DOF 4316 is effected by rack-and-pinion means 4316a and 4316b. When
pinion gear 4316b rotates, the rack translates along its
longitudinal axis in proportion to the amount of rotation of the
pinion gear, causing medical device 4300 to translate with it.
[0268] Reference is now made to FIG. 42, which presents a more
detailed illustration of means for effecting rotational motion
about DOF 4315. Worm gear and drive 4315a and 4315b are mated to
rack 4316a as described above. Worm gear 4315a is rigidly connected
to spur gear 4315d. Spur gear 4315d is mated to a second spur gear
4315c; in preferred embodiments of the invention, the axes of
rotation of gears 4315d and 4315c are substantially parallel. Spur
gear 4315c is rigidly connected to, and turns about substantially
the same axis as, intermediate gear 4315e. Intermediate gear 4315e
is mated to input gear 4315f; as illustrated in the figure, input
gear 4315f is disposed such that it may rotate in a plane different
from the plane of rotation of intermediate gear 4315e. In preferred
embodiments of the invention, the rotation axes of gears 4315e and
4315f are substantially perpendicular. Input gear 4315f is rigidly
connected to one end of internal tube 4315g and rotates about an
axis substantially coincident with the longitudinal axis of 4315g.
The sequence of steps that leads to rotational motion about DOF
4315 is thus as follows: rotation of internal tube 4315g drives
rotation of input gear 4315f, which drives simultaneous rotation of
intermediate gear 4315e and spur gear 4315c. Rotation of spur gear
4315c drives rotation of spur gear 4315d and hence of worm drive
4315a. Rotation of worm drive 4315a drives rotation of worm gear
4315b, which due to its inability to rotate relative to rack 4316a,
causes rotation of rack 4316a and hence of medical device 4300
located within. This rotational motion is thus independent of any
other motion of the device or of the connecting means as a
whole.
[0269] Reference is now made to FIG. 43, which illustrates in more
detail means for effecting translational motion about DOF 4316.
Pinion 4315b (the pinion is not visible in this view) is fixed in
place relative to the gear assembly, but is free to rotated about
its principal axis, and is mated to spur gear 4316c. Spur gear
4316c is connected by a fixed axle to a second spur gear 4316d such
that the two gears rotate in tandem. The second spur gear 4316d is
mated to intermediate gear 4316e. In preferred embodiments of the
invention, the axis of rotation of intermediate gear 4316e is
substantially parallel to the axle connecting spur gears 4316c and
4316d. In some embodiments of the invention, intermediate gear
4316e is rigidly connected to, and turns in tandem with, a second
intermediate gear with a gear ratio other than 1:1. Intermediate
gear 4316e (or the second intermediate gear in those embodiments
that comprise it) is mated to input gear 4316f. In preferred
embodiments of the invention, the axis of rotation of input gear
4316f is substantially perpendicular to that of intermediate gear
4316e. Input gear 4316f is rigidly connected to internal tube 4316g
and rotates about an axis substantially coincident with the
longitudinal axis of internal tube 4316g. Thus, translational
motion of medical device 4300 is effected as follows: rotation of
internal tube 4316g and hence of input gear 4316f drives rotation
of intermediate gear 4316e. Rotation of intermediate gear 4316e
then drives rotation of spur gear 4316d. Since spur gear 4316c is
physically connected to spur gear 4316d, rotation of the latter
necessarily causes rotation of the former at the same angular
velocity. Rotation of spur gear 4316c then drives rotation of
pinion 4316b, which forces translational motion of rack 4316a and
hence of the medical device contained within.
* * * * *