U.S. patent application number 10/153327 was filed with the patent office on 2002-10-10 for system and method for sample positioning in a robotic system.
Invention is credited to McNeil, John.
Application Number | 20020146347 10/153327 |
Document ID | / |
Family ID | 23630157 |
Filed Date | 2002-10-10 |
United States Patent
Application |
20020146347 |
Kind Code |
A1 |
McNeil, John |
October 10, 2002 |
System and method for sample positioning in a robotic system
Abstract
A system and method for positioning a sample, or cargo, with
respect to a device in a robotic system is provided. The system
includes a macro positioning system for "gross" movement of the
sample between stations and a micro positioning system for
precisely locating the sample in a predetermined location at a
station with respect to a device that will interact with the
sample. The macro positioning system provides a positioning
mechanism for the general movement of a sample along a pathway
between various destinations or stations wherein the sample is
"grossly" positioned with respect to the station. Once at the
station, the micro positioning subsystem disposed between a sample
carrier and the station provides a positioning mechanism for
"precisely" positioning the sample in a predetermined location at
the station with respect to a device that will interact with, or
perform some function on, the sample. The system and method provide
for multiple sample carrying robots having autonomous navigation
thereby providing flexibility and stacker-like queuing for near
100% device utilization.
Inventors: |
McNeil, John; (La Jolla,
CA) |
Correspondence
Address: |
WOODCOCK WASHBURN LLP
ONE LIBERTY PLACE, 46TH FLOOR
1650 MARKET STREET
PHILADELPHIA
PA
19103
US
|
Family ID: |
23630157 |
Appl. No.: |
10/153327 |
Filed: |
May 22, 2002 |
Related U.S. Patent Documents
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
|
|
10153327 |
May 22, 2002 |
|
|
|
09411748 |
Oct 1, 1999 |
|
|
|
6429016 |
|
|
|
|
Current U.S.
Class: |
422/63 ; 422/65;
422/67; 436/43; 436/47; 436/48 |
Current CPC
Class: |
G01N 2035/0491 20130101;
G01N 2035/0494 20130101; G01N 2035/00782 20130101; Y10T 436/114165
20150115; G01N 35/0099 20130101; G01N 2035/0489 20130101; Y10T
436/113332 20150115; G05D 2201/0216 20130101; Y10T 436/11 20150115;
Y10T 436/114998 20150115; Y10T 436/115831 20150115; G05D 1/0291
20130101 |
Class at
Publication: |
422/63 ; 422/65;
422/67; 436/43; 436/47; 436/48 |
International
Class: |
G01N 035/00 |
Claims
What is claimed is:
1. A positioning system for automated sample movement and
positioning comprising: a macro positioning subsystem for moving
one or more transporters carrying a sample between one or more
stations having a device; and a micro positioning subsystem
disposed between said transporters and said station for precisely
locating said transporters, and thus said sample, with respect to
said device thereby allowing accurate interaction of said device
with said sample.
2. The positioning system of claim 1, wherein said macro
positioning subsystem comprises: a predetermined track system
connecting each of said stations; a plurality of transporters
disposed along said track system; and a navigational system for
controlling the movement of said transporters along said track
system.
3. The positioning system of claim 2, further comprising one or
more sidings, wherein said plurality of robots running on said
track system and said sidings comprise a queuing system which
provides stacker-like queuing of said robots for near full device
utilization.
4. The positioning system of claim 2, further comprising a
controller disposed on-board said robot for controlling said
navigational system.
5. The positioning system of claim 1, wherein said micro
positioning subsystem comprises: a first locating structure formed
on one of said transporter and said station; and a second locating
structure formed on the other one of said transporter and said
station for cooperating with said first locating structure to
precisely locate said transporter and thus said sample with respect
to said device at said station.
6. The positioning system of claim 5, wherein said first locating
structure comprises one or more projections formed on said
transporter and said second locating structure comprises one or
more recesses formed in said station, wherein said projections
cooperate with said one or more recesses to precisely locate said
transporter with respect to said device.
7. The positioning system of claim 5, wherein said first locating
structure comprises one or more projections formed on said station
and said second locating structure comprises one or more recesses
formed in said transporter, and wherein said projections cooperate
with said one or more recesses to precisely locate said transporter
with respect to said device.
8. The positioning system of claim 5, wherein said first locating
structure comprises three projections and said second locating
structure comprises three recesses.
9. The positioning system of claim 5, wherein said first locating
structure and said second locating structure extend in a direction
substantially perpendicular to a plane defined by a working
surface.
10. The positioning system of claim 5, wherein said first locating
structure and said second locating structure extend in a direction
substantially parallel to a plane defined by said working
surface.
11. The positioning system of claim 2, wherein said track system
comprises one of a rail follower system, a line follower system, a
slot follower system, a light follower system, a magnetic follower
system, and a channel follower system.
12. The positioning system of claim 1, wherein said transporter
provides for autonomous navigation.
13. The positioning system of claim 1, wherein said transporter
further comprises: a body; a track engagement mechanism for
engaging said track system; a sample holding device disposed on
said body for holding said sample; an on-board controller for
executing one or more navigational instructions; a memory for
storing said navigational instructions; a propulsion mechanism for
propelling said transporters along said track system; and a power
supply for driving said propulsion mechanism.
14. The system of claim 1 further comprising an error correction
system and a collision avoidance system controlled on-board said
transporter, wherein said error correction system corrects a
positioning of a lost robot along said pathways and wherein said
collision avoidance system provides for avoidance of one or more of
side, rear-end, and front-end collisions.
15. A system for the manipulation of chemical reaction matrices
comprising: a chemical reaction matrix; a transporter having a
locating fixture thereupon, said transporter for moving said matrix
among one or more locations; and at each of said locations; and a
cooperating location fixture which cooperates with said locating
fixture to locate said matrix in a predetermined location in
space.
16. The system of claim 15 wherein said locating fixture comprises
one or more projections.
17. The system of claim 15 wherein the cooperating locating fixture
comprises an array of depressions adapted to receive said
projections.
18. The system of claim 17 wherein said projections are
self-centering in said depressions.
19. The system of claim 15 wherein said matrix is a multi-well
plate.
20. The system of claim 15 further comprising a digital controller,
wherein said transporter is under operative control of said digital
controller.
21. The system of claim 20 wherein said digital controller is
located onboard said transporter.
22. The system of claim 15 further comprising a track system,
wherein the transporter moves along predetermined pathways among
said locations defined by said track system.
23. The system of claim 15 wherein preselected claimed or
biological reactions take place at at least some of said
locations.
24. The system of claim 15 further comprising a robotic reagent
delivery apparatus at at least one of said locations.
25. The system of claim 15 wherein the matrix is reproducibly in
register at each of said locations to an accuracy of about 5
mm.
26. The system of claim 15 wherein the matrix is reproducibly in
register at each of said locations to an accuracy of about 1
mm.
27. The system of claim 16 wherein the matrix is reproducibly in
register at each of said locations to an accuracy of 0.5 mm.
28. The system of claim 15 wherein the matrix is reproducibly in
register at each of said locations to an accuracy of 0.1 mm.
29. A method for moving and positioning samples in a robotic system
comprising: (a) providing predetermined pathways connecting one or
more stations; (b) disposing one or more sample carrier
transporters along said pathways; (c) activating a macro
positioning system to move each of said transporters along said
pathways to a predetermined station; (d) macro positioning each
said transporters with respect to one of said stations; (e)
activating a micro positioning system disposed between said
transporter and said station; (f) micro positioning a sample on
said transporter with respect to a device at said station; and (g)
performing a function on said sample using said device.
30. The method according to claim 29, further comprising providing
a track system connecting said stations thereby defining said
predetermined pathways.
31. The method according to claim 29, further comprising
identifying said transporter at said station as a transporter to be
worked on by said device.
32. The method according to claim 29, further comprising
deactivating said micro positioning system once said device has
completed interacting with said sample, and continuing said
movement of said transporter along said pathways.
33. The method according to claim 29, further comprising avoiding
collision between transporters using a collision avoidance system
disposed between.
34. The method according to claim 33, further comprising avoiding
one or more of a side collision, a rear-end collision, and a front
collision using one or more indicator devices and one or more
sensors to indicate and sense a robot position relative to another
robot.
35. The method according to claim 29, further comprising
establishing a communications link between said transporter and
said station and exchanging identification data and navigational
instructions.
36. The method according to claim 35, further comprising
identifying said transporter as being a registered transporter for
interaction with a device at said station using an identification
system disposed between said transporter and said station.
37. The method according to claim 29, further comprising correcting
errors in the location of said transporters at a station or within
said system using an error recovery system.
38. The method according to claim 37, further comprising one or
more of loading a set of default instructions from said on-board
controller and loading a new set of navigational instructions from
one of said stations.
39. A navigation system located on-board a transporter for
controlling the movement of said transporter around a pathway of a
robotic system comprising: a controller located on-board said
transporter; a communications system for establishing a
communications link between said transporter and a station; an
identification system for identifying whether said transporter is
at a correct station; an error recovery system located on-board
said transporter for correcting the positioning of said
transporter; and a collision avoidance system located on-board said
transporter for avoiding collisions as between transporters.
40. The navigation system of claim 39 wherein scheduling
instructions are passed to the on-board controller from a central
controller via said communication link between said station and
said transporter.
41. The navigation system of claim 39 wherein navigational
instructions are passed to the robot via the track system wherein
said central controller sends a plurality of navigational
instructions down the track system and the robot and on-board
controller samples and selects instructions based one or a shortest
and a less congested route between two stations.
42. The navigation system of claim 39 wherein the robot makes all
the navigational decisions.
43. A storage system for the storage of a sample in a robotic
system comprising: a vertical support structure; a plurality of
storage devices forming levels one on top of the other supported by
said support structure; a track system disposed between and
connecting said levels; and a plurality of sample carrying robots
disposed along said track system for interacting with one or more
of said storage devices.
44. The storage system of claim 43 wherein said track system
comprises a substantially vertical portion disposed along said
support structure, wherein said robots climb up said track system
in a direction that is substantially vertical.
45. The storage system of claim 44 wherein each of said robots
comprises; a body; a gimbaled platform attached to said body; a
sample plate disposed on said platform; and an opening formed in a
bottom of said body for sliding said plate between said platform
and a storage mechanism.
46. The storage system of claim 44 further comprising a track
gripping mechanism.
47. The storage system of claim 46 wherein said track gripping
mechanism comprises one of a magnetic attraction, a cog rail, pins,
rods, hooks.
48. The storage system of claim 43 wherein said track system
comprises a ramp system that connects each of said shelves.
49. The storage system of claim 48 wherein said ramp system
comprises one or more spiral ramps, wherein each spiral in said
ramp raises said track to a next level.
50. The storage system of claim 43 further comprising a device for
transferring said sample between said robot and said storage
device.
51. A method of storing samples in a robotic system comprising:
providing a plurality of vertically stacked storage devices;
disposing a track system vertically connecting each of said storage
devices; running one or more sample carrying robots along said
track system between said storage devices; and interacting between
at least one of said robot and at least one of said storage
device.
52. The method of claim 51 further comprising running along a
linear track system disposed substantially vertical.
53. The method of claim 52 further comprising gripping said track
system using a track gripping mechanism disposed between said robot
and said track system.
54. The method of claim 51 further comprising running along a
ramped track system.
Description
FIELD OF THE INVENTION
[0001] The present invention relates in general to automated
systems for positioning a sample, or cargo. More particularly, the
present invention relates to a robotic positioning system and
method that include a gross positioning system for movement of the
sample between workstations and a precision positioning system for
precisely locating the sample at the workstation with respect to a
device that will interact with the sample.
BACKGROUND OF THE INVENTION
[0002] Various industries require automated systems for the general
movement of goods between workstations and a more precise
positioning system for precisely locating the goods at each
workstation for manipulation of the goods by a device at the
workstation. For example, for pharmaceutical research and clinical
diagnostics, there are several basic types of automation systems
used. Each of these conventional approaches is essentially a
variant on a method to move liquid or dry samples from one
container to another, and to perform other operations on theses
samples, such as optical measurements, washing, incubation, and
filtration. Some of the most common automated liquid handling
systems include systems such as those manufactured by Beckman,
Tecan, and Hamilton.
[0003] These conventional automation systems share the
characteristic that sample transfer and manipulation operations are
carried out by workstations, or devices, of some kind. These
workstations can be used separately for manual use, or
alternatively, can be joined together in automated systems so the
automation provider can avoid having to implement all possible
workstation functions. Another shared characteristic is that
samples are often manipulated on standardized "microtiter plates."
These plates come in a variety of formats, but typically contain 96
"wells" in an 8 by 12 grid on 9 mm centers. Plates at even
multiples or fractions of densities are also used.
[0004] In a first automation system, various workstations are
linked together with one or more plate carrying robots. These
robots can be a cylindrical or articulated arm robots, and can be
located on a track to extend their range. A variant on this design
is a system with one or more Cartesian robots operating over a work
surface. In the Cartesian case, the robots can carry plates and
also perform liquid transfer operations. These systems are
controlled by a central control system with a scheduler. Most
schedulers schedule the operations of one protocol performed many
times, making sure that all time constraints are met, including,
for example, incubation periods. The primary advantage of such a
system is complete hands free operation. Accordingly, these systems
can run for hours or days at a time with no human intervention.
However, these types of systems have several disadvantages.
[0005] For example, individual devices can only be kept busy 30-70%
of the time due to scheduling and collision avoidance constraints.
In addition, the system has an upper limit on scalability. This
second disadvantage comes about due to upper limits in achievable
servo system dynamic range. All plate and liquid transfer operation
require precision of about 0.1-0.5 mm. To do meaningful work, a
work area of at least one square meter is typically needed. Servo
systems that can achieve this dynamic range are expensive and
relatively large. To increase the useable work area, dynamic range
must be increased, without compromising the accuracy of the system.
For these reasons, the largest linear dimension typically used is
three meters. Smaller plates can increase the amount of work that
can be accomplished in a given area, however, the necessary size of
the high dynamic range servos prevents plates being used that are
much smaller than the current standard.
[0006] A second basic type of automation can be created by using
plate stackers. For example, an input stacker is placed on one side
of a device such as a liquid transfer system or optical plate
reader, and an output stacker is placed on the other. Plates are
fed from the bottom of the input stacker to the device by conveyer
belt or pick-and-place arm. When the device finishes an operation,
the plate is similarly placed on the bottom of the output stacker.
Stackers often use removable cartridges so that approximately 20
plates at a time can be carried from device to device. The
cartridges are usually carried manually, however at least one
system exists that uses an articulated arm robot to move the
stackers between devices. Plate incubation is achieved by simply
setting the stack in an incubator. The primary advantages of this
automation approach are that the devices can be utilized nearly
100% of the time, and that it is relatively inexpensive to
implement. However, this type of system has several disadvantages,
including that the system is usually not fully automatic, that the
plates cannot be processed with identical timing because the stacks
are first in, last out, and that system flexibility is severely
limited because stacks of plates must all be run through the same
processing steps.
[0007] Another basic type of automation system is an extension of
the above stacker type system wherein multiple devices are placed
in a row on a lengthened conveyer. Although this system offers even
more potential throughput, this type of system results in even less
system flexibility. A further difficulty is that this type of
system cannot accommodate incubation periods as there are no first
in, first out stackers.
[0008] What is needed by various automation industries, such as the
pharmaceutical discovery, clinical diagnostics, and manufacturing
industries, is a sample positioning system and method that overcome
the drawbacks in the prior art. Specifically, a system and method
for providing a gross positioning system for moving samples between
various stations coupled with a precision positioning system at
each station for precisely locating the samples with respect to a
device that will interact with the samples. Therefore, a need
exists for an accurate sample positioning system and method that
overcome the drawbacks of the prior art.
SUMMARY OF THE INVENTION
[0009] The present invention is directed to a system and method for
positioning a sample, or cargo, with respect to a device in a
robotic system. The system and method of the present invention
provide both flexibility and scalability due to the benefit of
queuing and the reduction in required dynamic range of the servos
(e.g., actuators). The system and method of the present invention
provide the flexibility of robots having autonomous navigation and
stacker-like queuing for near 100% device utilization.
[0010] The system of the present invention includes a macro
positioning system for "gross" movement of the sample between
stations and a micro positioning system for precisely locating the
sample at a station with respect to a device that will interact
with the sample. The macro positioning system provides a
positioning mechanism for the general movement of a sample along
pathways formed between various destinations, or stations, wherein
the sample is "grossly" positioned with respect to the station.
Once at the station, the micro positioning subsystem disposed
between a sample carrier, or robot, and the station provides a
positioning mechanism for "precisely" positioning the sample in a
predetermined location at the station with respect to a device that
will interact with, or perform some function on, the sample. The
system and method combine technologies for macro positioning
between stations, micro positioning at each station, and device
interaction with the sample at each station in a robotics system
for accurately positioning a sample with respect to a device that
will interact with the sample.
[0011] The macro position system preferably includes some type of
track system disposed between and connecting the various stations,
and thus defining the pathways. The track system of the present
invention can comprise any standard track system, including for
example, a grid-type, miniature railroad type, line follower-type,
slot-follower, light or laser-follower, magnetic-follower. The
track system defines one or more pathways and intersections
connecting the various pathways which allow the robots to travel
between the various stations.
[0012] The system includes one or more carriers, transporters, or
robots that carry a sample, or cargo, around the pathways. Each
robot includes a body, a track engagement mechanism, a sample
holding device, a power supply, and a propulsion mechanism for
propelling the robot along the pathways. Preferably, the robots of
the present invention have an on-board controller which provides
for autonomous navigation of the individual robots between the
various stations in the system. Multiple robots running on a track
system provides system flexibility and stacker-like queuing for
near 100% device utilization. Autonomous navigation of the robots
allows greater system flexibility because each robot individually
controls its own navigation thereby reducing required dynamic range
of the servos. The robots are programmed to negotiate the track
system and travel to predetermined destinations within the robotic
system, where they interact with a device. In addition, the system
and robots provide for collision avoidance, error recovery, robot
to station communications/identification, and provide more
flexibility and stacker-like queuing for near full device
utilization.
[0013] The micro positioning system of the present invention is
preferably disposed between the robot and the stations and is used
to precisely locate the robot, and thus the sample, in a
predetermined location in space. The micro positioning system
includes a locating fixture on one of the robot and the station and
a cooperating location fixture on the other of the robot and the
station. Preferably, the location fixture includes one or more
projection extending from the robot and the cooperating location
fixture includes one or more depressions formed at the station. The
projections fit within the depression to form a self-centering and
precision fit.
[0014] A further embodiment within the scope of the present
invention is directed to a method of positioning a sample, or
cargo, in a robotic system with respect to a device located at a
station in the system. The method includes providing for the gross
positioning or movement of a sample along pathways formed between
various stations and also for the precision positioning of the
sample in a predetermined location in space relative to a device at
the station in order for the device to be able to interact with the
sample. The method comprises providing a plurality of predetermined
pathways connecting one or more stations, disposing one or more
robots along the pathways, activating a macro position system,
which is preferably located on-board the robot, to move the robots
around the pathways, "grossly" positioning the robots with respect
to a station, activating a micro positioning system, which is
preferably disposed between the robot and the station, micro
positioning the robot, and thus a sample on the robot, in a
predetermined location in space with respect to a device at the
station, and interacting with, or performing some function on, the
sample with the device based on the identification.
[0015] Preferably, the method of the present invention also
comprises using some type of track system between the stations thus
defining the pathways and providing a mechanism for the robots to
travel along. In addition, the method preferably further comprises
establishing a communications link and identifying the robot to
determine whether the robot is at a correct location. Furthermore,
the method can further comprise recovering lost robots using an
error recovery system and avoiding collisions between robots using
a collision avoidance system.
[0016] The system and method of the present invention provide for
improved scalability both toward large and small systems, unlimited
flexibility, allowing any sample to be processed following any
protocol, stacker-like queuing for near 100% device utilization,
and completely hands free operation.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] The foregoing and other aspects of the present invention
will become apparent from the following detailed description of the
invention when considered in conjunction with the accompanying
drawings. For the purpose of illustrating the invention, there is
shown in the drawings an embodiment that is presently preferred, it
being understood, however, that the invention is not limited to the
specific methods and instrumentalities disclosed. In the
drawings:
[0018] FIG. 1 is a schematic diagram of an exemplary layout of the
positioning system in accordance with the present invention;
[0019] FIGS. 2A, 2B, 2C are graphical representations of an
exemplary queuing system in accordance with the present
invention;
[0020] FIG. 3 is a schematic diagram of an exemplary grid type
track system for movement of the robots between stations in
accordance with the present invention;
[0021] FIG. 4 is a schematic diagram of an intersection of an
exemplary slot follower type track system for movement of the
robots between stations in accordance with the present
invention;
[0022] FIG. 5A is a plan view of an intersection for an exemplary
channel type track system for movement of the robots between
stations in accordance with the present invention;
[0023] FIG. 5B is a cross-sectional view of the channel type track
system of FIG. 5A taken along line 5B-5B;
[0024] FIG. 6 is a flow chart of an exemplary method of navigation
in accordance with the present invention;
[0025] FIG. 7 is a block diagram of an exemplary central controller
connected to the stations in accordance with the present
invention;
[0026] FIG. 8A is a top view of an exemplary robot of the system of
FIG. 1;
[0027] FIG. 8B is a side view of the exemplary robot of FIG.
8A;
[0028] FIG. 8C is a top view of the exemplary robot of FIG. 8A with
the sample holding device removed for clarity;
[0029] FIG. 9A is a top view of another exemplary robot of the
system of FIG. 1 with the sample holding device removed for
clarity;
[0030] FIG. 9B is a side view of the exemplary robot of FIG.
9A;
[0031] FIG. 9C is a top view of the exemplary robot of FIG. 9A with
the controller removed for clarity;
[0032] FIG. 10 is a block diagram of an exemplary robot controller
to be used with a robot of FIG. 8 and FIG. 9;
[0033] FIG. 11A is a top view of an exemplary robot micro
positioning system in accordance with the present invention;
[0034] FIG. 11B is a side view of the micro positioning system of
FIG. 11A;
[0035] FIG. 12 is a block diagram of an exemplary robot
identification and communication system in accordance with the
present invention;
[0036] FIG. 13A is a schematic diagram of an exemplary device of
the system of FIG. 1;
[0037] FIG. 13B is a schematic diagram of another exemplary device
of the system of FIG. 1;
[0038] FIG. 14 is a schematic diagram showing an exemplary vertical
storage device in accordance with the present invention;
[0039] FIG. 15 is a flow chart of an exemplary method of robot
identification and error correction in accordance with the present
invention;
[0040] FIGS. 16A and 16B are schematic diagrams showing an
exemplary track merger collision avoidance system in accordance
with the present invention;
[0041] FIGS. 17A and 17B are schematic diagrams showing an
exemplary rear-end collision avoidance system in accordance with
the present invention;
[0042] FIG. 18 is a flowchart of an exemplary method of side and
rear-end collision avoidance in accordance with the present
invention;
[0043] FIG. 19 is a schematic diagram of another exemplary
collision avoidance system in accordance with the present
invention; and
[0044] FIG. 20 is a flow chart of another exemplary method of
collision avoidance in accordance with the collision avoidance
system of FIG. 19.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0045] The present invention is directed to a highly accurate
system and method for the movement and positioning of a sample in a
robotic system. The system and method of positioning the sample, or
cargo, within the robotic system use a gross positioning subsystem
(hereinafter also referred to as "macro positioning system") in
combination with a precision positioning subsystem (hereinafter
also referred to as "micro positioning system"). The macro
positioning system provides a positioning mechanism for the general
movement of a sample along a pathway between various destinations,
or stations, wherein the sample is "grossly" positioned with
respect to the station. Once at the station, the micro positioning
system provides a positioning mechanism for "precisely" positioning
the sample in a predetermined location at the station with respect
to a device that will interact with, or perform some function on,
the sample.
[0046] The subject invention combines technologies for macro
positioning between stations, micro positioning at each station,
and device interaction with the sample at each station in a
robotics system for accurately positioning a sample to be worked on
with respect to a device that will perform the work. This provides
for near unlimited range of the system with very precise final
positioning at each destination at relatively low cost. Preferably,
the micro positioning system positions the sample with respect to
the device to a magnitude in the order of about 10.times. or better
than the macro positioning system.
[0047] Furthermore, the present invention can provide for
autonomous navigation wherein the robots make all navigational
decisions, including turning, speed, collision avoidance, and error
recovery. System flexibility and scalability result in part as a
by-product of being able to afford many sample moving robots, hence
they can sit around waiting in line for a device to be free (thus
providing stacker-like queuing for near full device
utilization).
[0048] FIGS. 1, 3, 4, and 5 illustrate several exemplary
embodiments of the macro positioning system 2, which provides for
the gross movement of one or more sample carriers 3 (hereinafter
also referred to as "transporters" or "robots"), between one or
more destinations 4 (hereinafter also referred to as "stations" or
"workstations"). As shown in FIG. 1, the present invention has
predetermined pathways 5 defined between the one or more stations 4
in the system 1. As shown in FIGS. 1, 3, 4, and 5, each of the
following embodiments preferably has some kind of track system 6
disposed between the various stations 4 that one or more robots 3
travel along and follow.
[0049] The present invention is not limited to a macro positioning
system 2 having a track system 6. For example, the robots 3 could
be constructed to navigate the pathways 5 guided by any standard
navigational means, including fixed beacons disposed about the
desired pathway of a given application, a G.P.S., etc.
[0050] As shown in FIG. 1, the track system 6 defines one or more
predetermined pathways 5 disposed between the various stations 4.
Each station has a device 8, such as a plate washer, pipettes, a
reader, etc., for interacting in some way with the robot 3 and/or a
sample 9 thereon. Intersections 10 are formed along the various
pathways 11 where the pathways diverge and converge, and where
devices are located. One or more siding 11 can be provided at each
station 4 for allowing a robot 3 to exit a pathway 5 onto the
siding 11. The siding 11 for a device 8 allows other robot 3
traffic to pass while the robot 3 and device 8 interact. As shown
in FIG. 1, each siding 11 may comprise a relatively short siding
11a, a longer siding 11b allowing a queue of robots to wait for a
slow device, or a relatively very long siding 11c which can hold a
very long queue for slower devices. An indicator device (not shown)
can be provided at each intersection 10 and at each station 4 which
can be detected by a sensor device (not shown) on each robot, for
determining when a robot 3 is at an intersection 10 or station
4.
[0051] As shown in FIGS. 2A through 2C, the robotic system can be
viewed as a queuing system, where queue congestion grows
asymptotically as device demand approaches robot capacity, as shown
in FIG. 2A. The value of capacity (e.g., the number of robots)
grows with increased congestion resulting form devices having to
wait for another robot, as shown in FIG. 2B. A standard queue
function, such as in an M/M/S queue, can be used to represent the
probability of a device having to wait and to approximate the value
of more robot carrying devices as a function of congestion, as
shown in FIG. 2C. The system and method of the present invention
address this problem by providing the flexibility of multiple
robots traveling on a track system thereby providing stacker-like
queuing for near 100% device utilization, as well as robots having
autonomous navigation.
[0052] The system 1 can include a cross-connection pathway 12 for
coupling the main system 1 to one or more subsystems (not shown).
The cross-connection pathway 12 can connect the main system 1 to a
subsystem that is a few meters away, or even in another building
that may be hundreds of meters or kilometers away. Alternatively,
the cross-connection pathway 12 can also connection one or more
subsystems positioned above or below the main system 1, such as,
for example in a stackable type arrangement.
[0053] The system 1 includes a sample, or cargo, holding device 13,
such as a plate or matrices, for holding the sample 9 on the robot.
As shown in FIG. 1, for example, liquid transfer devices 8a move
liquid from a storage plate 13 on one robot to another. This can be
accomplished by sending the two robots 3 to the two appropriate
parallel tracks 6a, 6b which travel under the same device 8, such
as a pipette or pin transfer device.
[0054] The system 1 layout described above with respect to FIG. 1
is two dimensional (e.g., the system is contained within a plane
defined by the X, Y coordinates). Alternatively, the system 1 could
be built on multiple levels, or in three dimensions for even more
operations per cubic meter of lab space (e.g., the system could be
contained within a space defined by the X, Y, and Z
coordinates).
[0055] The topology of all the embodiments shown in FIGS. 1, 3, 4,
and 5 is preferably designed such that every intersection 10 has a
fork design, with only left and right choices. Accordingly, as
shown, a single pathway 5 splits into two pathways (e.g.,
diverges). The track system 6 is preferably arranged such that
travel on any given section or pathway 5 is generally only in one
direction, like for example, an automobile freeway system.
Accordingly, to return to the same position, a robot 3 would make a
complete circuit around one of the loops in the system 1.
Preferably, the topology is further limited so that only two
pathways 5 ever come together (e.g., converge into one path) at
once.
[0056] The system can also provide for reverse direction of the
robots (e.g., backing up). Preferably, this reverse direction
capability is provided at at least the local regions where the
robots are precisely positioned. For the grid-type track system, as
described more fully herein below with reference to FIG. 3, this is
relatively easy to implement by, for example, having the on-board
controller simply change the "back" to the "front" and reversing
the direction of rotation of the wheels. For the slot and channel
type track systems, this can be accomplished, for example, by
disposing a pair of side rails along side the main pathway, or a
rear-end guide pin, to prevent the robot from jack-knifing as it
attempts to reverse directions.
[0057] FIG. 3 shows a grid-type, or array-type, track system 6c
which is designed to create an arbitrarily large work surface on
which robots 3 carrying plates 13 having a sample 9 are set to be
moved between workstations 4 having devices 8 which interact in
some way with the sample 9. Plates 13 are moved from one location 4
to another location 4, and to devices 8 and bulk storage 90, by
robots 3 which can travel in X or Y directions along the grid
system 6c. Interaction between the cargo 9 (e.g., cargo
manipulation), such as, for example, liquid or dry sample handling,
can be accomplished by devices 8 at each station 4 or similar
robots 3 which carry devices 8, such as pipettes or pin transfer
tools. Because these robots 3 are inexpensive, a variety of pipette
and pin sizes can be accommodated by multiple dedicated robots.
[0058] FIG. 3 shows the basic layout of these robots 3 on the grid
6c. Rails 14 are provided upon which the robots 3 run. As shown,
each robot has a set of "X" wheels 15a and a set of "Y" wheels 15b.
If the robot 3 is centered on a grid location and either changing
direction or interacting with a plate, both sets of wheels are
raised and the robot rests on its micro positioning subsystem 60,
such as, for example, indexing feet, as described herein below in
more detailed with respect to FIGS. 11A and 11B. If the robot 3
wants to move on the "X" direction, it lowers its "X" wheels 15a
and rolls in that direction. If it wants to change to travel in the
"Y" direction, it raises the "X" wheels 15a while at an
intersection 10 (plate grid location), then lowers the "Y" wheels
15b. Note that this also realigns the robot ensuring that the new
wheel set will properly engage.
[0059] In another embodiment of the track system (not shown), the
robots can run on miniature railroad tracks, such as, for example,
model train tracks. Intersections can be detected by a mechanical,
electrical, or IR sensor. The intersections can be switched either
by conventional moving switches, or by open switches, such as those
used by trolleys. In the first case, the switches are either thrown
by a mechanical arm on the robot as it approaches, or by a signal
(e.g., an IR or an electrical signal) to a track mounted switch
actuator. In the second case, a turning force is applied to the
wheels as they pass over a switch causing the wheels to turn
thereby causing the robot to go one way or the other.
[0060] In another embodiment (not shown), the track system can
comprise a line follower-type track system. In this embodiment, the
robots follow lines of contrasting color to the work surface in the
infrared. This can be accomplished, for example, using three
reflective sensors. The computer steers left or right depending on
which sensors detect the line. When an intersection is detected,
the robot steers through it by ignoring the sensor on the side it
does not want to go. This causes the robot to follow the edge of
the line in the direction it wants to go. It does this for a
predetermined distance and then it resumes normal line tracking.
Preferably, this embodiment includes a power supply on-board the
robot to power the robot, such as rechargeable batteries. A robot
having an on-board power supply can return to a charging station
periodically for recharge or battery swap.
[0061] In another embodiment of the track system, the track system
comprises a slot or channel follower-type track system. In these
embodiments, the robots follow a slot with a pin, similar to a slot
car, or run in a channel as wide as the robot.
[0062] FIGS. 4 and 5 shows methods or negotiating an intersections
10 for two types of track systems 6. As shown in FIG. 4, guide
slots 19a and 19b can be provided in addition to the main slot 16,
which forks into left slot 17, and right slot 18. Upon detection of
an intersection 10, an auxiliary pin (not shown) can be lowered
from the robot on either the left or right side of the robot body,
depending on the direction desired. This pin forces the robot to
follow the desired path through the intersection 10. Optionally,
the pin in the main slot 16 may be removed or lifted during travel
through the intersection to allow for tolerances in following the
auxiliary slot 19a or 19b. In a second alternative embodiment (not
shown), wherein the robot follows a slot type track system 6d, with
a pin, another method of choosing a direction is by causing the
wheels of the car to turn, pushing the pin to the side of the slot
desired to turn.
[0063] FIGS. 5A and 5B show a channel type track system 6e. As
shown in FIG. 5B, where the robot (not shown) runs in a channel 20
as wide as its body width, the top of the channel walls 21 is
preferably at least partially above the work surface level 22. To
choose a direction at an intersection 10, an arm (not shown)
connected to the robot body can be lowered which hooks over a left
21a or right wall 21b to force the robot to hug the side wall 21 in
the direction of choice.
[0064] FIG. 6 is a flowchart showing an exemplary method for
navigation in accordance with the present invention. As shown in
FIG. 6, the robot gets instructions, such as, for example, a
left/right list, to the new destination, or station, at step 100.
The propulsion system is activated causing the robot to drive, or
move, forward, at step 105. The robot continues along the pathway
as long as it does not sense an intersection. When the robot senses
that it has come to an intersection, at step 110, it then
determines whether there are more navigation instructions, at step
115. If there are more instructions the robot inserts/executes the
next set of instructions, at step 120, and then continues to drive
forward, back at step 105. The process of steps 100 through 120 are
repeated until it is determined that there are no more
instructions, at step 115. When the end of the list is reached, the
next intersection is assumed to be the destination, where the robot
stops and attempts to communicate with the device it is at.
[0065] Once no more instructions are detected, or a station is
detected, at step 115, the robot attempts to establish
communications with a device, at step 125. The robot determines, at
step 130, whether or not a communications link is established. If
no communications link is established, then the robot activates an
error correction, such as, for example, initiating a preprogramed
error recovery instruction, at step 135, and drives forward, at
step 105.
[0066] If a communications link is established and operating at
step 130, then the robot identifies itself to the device, at step
140. At step 145, it is determined whether the robot is at the
correct location. If the robot is not at the correct location, the
robot gets new instructions from a central controller, at step 150,
and then drives forward, at step 105.
[0067] If it is determined that the robot is at the correct
location, at step 145, then the device interacts with the robot
and/or sample on the robot, such as for example performing one or
more operations and/or manipulates a sample on the robot, at step
147. After the device has completed its interaction with the robot,
the robot gets new instructions, at step 150. The process then
continues, at step 105, and the robot drives forward.
[0068] Preferably the robot is capable of autonomous navigation.
Autonomous means that the controller that controls the movement of
the robot along the pathways as it travels around the system is
located on-board the robot. For example, the robot makes all the
navigational decisions, including when to turn, where to turn, what
route to take, what speed to travel at, when to stop, etc. In
addition, the navigational system provides for error correction and
collision avoidance, which are also preferably controlled on-board
the robot. Autonomous navigation of the robot provides system
flexibility and reduces system costs. Alternatively, the controller
for controlling the movement of the robot can be located in other
locations within the system, such as in the stations or devices, as
part of the central controller, etc. An intersection can be
detected by, for example, an optical, electrical, or mechanical
switch.
[0069] FIG. 7 is a schematic diagram of an exemplary central
controller 30 in accordance with the present invention. As shown,
each station 4 is coupled to the central controller 30 having a
microprocessor 31. The microprocessor 31 preferably generates the
routing information and can perform tracking and other processing
functions. Each station 4 can be connected to and communicate with
the central controller 30 using standard wired or wireless
techniques. This allows the central controller 30 to send
navigational instructions to each robot 3 via a communications link
or interface between the station 4 and the robot 3. The robots can
follow one or more protocols as defined by the central controller
30.
[0070] As shown, the microprocessor 31 can reside in a conventional
computer, such as a standard personal computer, which can comprise
the central controller 30 (e.g., 100 MHZ, 32 Mbyte DRAM, monitor,
keyboard, ports, hard drive, floppy drive, CD-ROM drive).
Alternatively, a microprocessor can reside within each station
4.
[0071] The microprocessor 31 is coupled to each station 4 via
conventional cables and/or printed circuit boards (PCBs) that can
be connected into slots on the computer, such as an ISA slot or a
PCI slot. Other conventional means for coupling the stations to the
microprocessor 31 can be employed, such as, for example, a standard
Ethernet, USB, or wireless connection.
[0072] The microprocessor 31 preferably provides navigational
instructions to the robots for the movement of the robots,
schedules the operation of the devices, and runs software held in
read only memory (ROM) 32. The processor 31 is connected via a bus
33 to the ROM 32, a random access memory (RAM) 34, another memory
such as an erasable programmable ROM (EPROM) 35, and an
input/output (I/O) controller 36. The RAM 34 is large enough to
hold at multiple protocols, robot and sample identification data,
and navigational instructions for each robot. The I/O controller 36
is connected to the appropriate circuitry and drivers (not shown)
for issuing commands and instructions to the stations 4.
[0073] FIGS. 8A, 8B, 8C, 9A, 9B, and 9C show two exemplary robot 3
embodiments in accordance with the present invention. As shown, the
robot 3 includes a body 40, a sample holding device 13, a micro
positioning system 60, a propulsion mechanism 42, and track
engagement mechanism 43. Preferably, the body 40 includes a
sub-frame 40a. Each robot 3 also includes a controller 44, a drive
system 45, and a power supply 46. The robot can include various
displays (not shown) and/or indicators (not shown) for showing a
state of the robot 3. Preferably, the robots 3 has an on-board
controller 44, an on-board drive system 45, and an on-board backup
power supply 46. For example, the on-board drive system 45 can be a
motor and gear system, and the on-board backup power supply 46 can
be a battery or a capacitor. In addition, the robot 3 can include
an identification system, a collision avoidance system, and an
error correction system.
[0074] The sample, or cargo, holding device 13 is used for hold one
or more samples 9, or individual pieces of a cargo, on the robot 3
for interaction with one or more of the devices 8. The sample
holding device 13 is preferably attached to or placed on top 41 of
the robot body 40, such as on top of the sub-frame 40a. For
example, an exemplary sample holding device for a typical
liquid-type handing system, as shown in FIG. 1 and in more detail
in FIGS. 7A and 7B, comprises a plate 13 having one or more wells
52, or cavities, formed therein.
[0075] The plate 13 can be, for example, any standard microtiter
plate format, such as a 96-well plate, a 384-well plate, a 1536
well plate, etc. The wells 52 may be varying depths, such as
shallow or deep well. The wells 52 may have a variety of shapes
based on the application and the samples that they will carry and
the wells can have a flat, a U-shaped, or a V-shaped bottom.
Preferably, the well plates 13 meet SBS standards, are made from
optically quality polystyrene to allow direct sample observation,
and have raised rims (not shown) to prevent cross-contamination.
Alternatively, the sample holding device 13 can include any other
size or type of container or platform depending on the particular
application, such as standard or non-standard sizes of, for
example, a vial, a test tube, a pallet, a cup, a beaker, a
matrices, etc.
[0076] This robotic sample positioning system 1 is conceived to be
implemented in multiple scales. For example, in a first embodiment
of the invention, the scale can be designed to work with standard
size microtiter plates. These standard plates are approximately 125
mm by 85 mm. The wells of a 96-well plate are on about 9 mm centers
and hold from about 200 .mu.l to about 1500 .mu.l depending on the
plate depth. This system could work with standard devices currently
available, such as, for example, plate washers, pipettes, plate
readers, etc. In another embodiment of the invention, the scale
could be significantly smaller. For example, a 96-well plate could
be approximately 16 mm by 12 mm, with wells on about 1 mm centers.
These wells would hold approximately 1 l. Liquid could be
transferred by a device, such as a micro-pin tool or a
piezo-pipette.
[0077] The robot 3 includes a propulsion system 42 for propelling
the robot 3 about the system 1 along the various pathways 5. Any
known technique for propelling a device can be used to propel the
robot 3 around the pathways 5 of the system 1. For example,
exemplary robot propulsion systems 42 can include an electric
propulsion system, such as an electric motor, a pneumatic
propulsion system, such as a fan or air powered firing pins, a
magnetic propulsion system, etc. Preferably, the robot propulsion
system 42 is located on-board the robot 3, as shown in FIGS. 9A and
9B. Motion control can include technologies, such as PWM servos,
motors with once per revolution encoders from rough speed
regulation and Nitinol thermally activated memory metals. The
motion controller can include a Motor Mind B and Mini SSCII (Serial
Servo Controller) manufactured by Solutions Cubed of Chico, Calif.
Alternatively, the propulsion system can be located along the
pathway such that it engages and propels the robot along the
pathway.
[0078] The robot 3 includes a power supply 46, which can comprise a
standard DC or AC supply, a battery, or a capacitor (not shown).
Preferably, during normal operating conditions the robot 3 is
powered via a standard DC or AC supply and has an on-board power
supply 46a for those periods of time wherein the normal power
supply may be temporarily interrupted or lost, as for example, when
the robot 3 is making turns or experiences a dirty stretch of track
6. The on-board power supply 46a preferably has sufficient power to
allow the robot to travel at least about 10 cm. The robots 3 can
derive power from the track 6 that they ride upon.
[0079] The track engagement mechanism 43 is attached to the body 40
and can include, for example, wheels, rollers, sliders, slots,
pins, etc. The track engagement mechanism 43 is used for engaging
the track system 6 thereby holding the robot 3 on the track system
6 and also for engaging the track system 6 thereby allowing the
robot 3 to move forward around the various pathways 5.
[0080] FIG. 10 is a block diagram showing an exemplary controller
44. Preferably, the robots 3 have on-board control computers. The
on-board computers are used to control and operate the robot,
including the autonomous navigation of the robot. Preferably, the
onboard computer includes a programming port 55 with the ability to
load programs remotely, a non-volatile RAM for both the program
loaded itself, with room for some program accessible RAM, an I/O
control pins which can drive PWM servos 56 (such as, for example,
remote control model airplane servos), perform bi-directional
serial communication 57, and one or more actuators 54. Also, the
robot controller is preferably self contained in a small package.
For example, one such computer is the Basic Stamp.TM. (model I or
II) manufactured by Parralax, Inc. FIG. 8 also shows the controller
connected to a motor controller 58 which is in turn connected to a
motor 59 for driving the propulsion mechanism 42, which in turn
drives the track engagement mechanism through a drive mechanism
(not shown), such as a set of gears or a pulley system.
[0081] Preferably, the controller 44 performs various functions,
including moving forward, activating the micro positioning system,
activating the robot identification process, operating the
collision avoidance system, operating the error correction system,
lighting or turning off indicator lamp(s), providing an audible
signal via the speaker, etc. A benefit of autonomous navigation is
that the proper movement of the robot between stations can occur
within each individual robot device, so that each robot has a high
dynamic range which keeps the cost of the system low and also
allows scalability of the system. This also enhances the
flexibility and versatility of the robot devices of the present
invention.
[0082] FIGS. 11A and 11B show an exemplary micro positioning
subsystem 60. The micro positioning subsystem 60 is disposed
between the robot 3 and the station 4, or device. As shown in FIG.
9, when a robot 3 reaches its destination, it precisely locates
itself in a predetermined location in space relative to the device
8 using the micro positioning subsystem 60. Preferably, the micro
positioning system 60 includes a locating fixture 61 on the robot 3
and a cooperating locating fixture 62 at each station 4.
Preferably, the micro positioning system 60 includes one or more
projections 61, or feet, extending from an underside 63 of the
robot body 40 and one or more depressions 62, or recesses, formed
in a top surface 64 of the working surface level 22 at a
station.
[0083] Preferably the number and shape of the locating fixture 61
and the cooperating locating fixture 62 are coordinated to match
one another. In addition, some tolerance is preferred between the
top end 65 of the depression 62 and the distal end 66 of the
projection 61, this tolerance allows for the gross positioning of
the robot 3 with respect to the station 4 and device 8 and also
assists in the locating, or lead-in, of the projections 61 into the
depressions 62. It is also preferred to round, or taper, the edges
of both the distal end 66 of the projections 61 and the top edge 65
of the depressions 62 openings in order to provide a smooth lead-in
thereby assisting in the locating of the projections 61 into the
depressions 62. Once the projections 61 are completely inserted
into the depressions 62, the distal end 66 of each projection 61
and the bottom 67 of each depression 62 preferably form a tight
clearance thereby providing for the precision positioning of the
robot 3 with respect to the station 4 and device 8.
[0084] As shown in FIGS. 11A and 11B, this can be accomplished by
the robot 3 lifting itself onto three hemispherical feet 61
attached to the robot body 40, preferably extending from an under
surface 63 of the robot 3, such as the under surface of a sub-frame
40a. These projections 61 drop, engage, or fit into three
conical-shaped depressions 62 formed in the top 64 of the working
surface level 22 at the station 4 and under the robot 3.
Preferably, these depressions 62 are indexed to the device 8 which
will interact with the robot 3. Preferably, the sub-frame 40a is
also the point of attachment for the plate or sample holding device
13.
[0085] This preferred micro positioning system 60 having three
points of contact for micro positioning the robot acts to precisely
locates the robot 3, and thus the plate 13, or sample device, in
six degrees of freedom, relative to the device 8, allowing accurate
manipulation of its samples 9, or cargo, depending on the station 4
the robot 3 is at. Preferably, the micro positioning system locates
the sample 10.times. or better than the macro positioning system.
For example, in an exemplary robotic system involving biometric
samples contained in standard 96-well plates, the robot can be
positioned near, for example, a pipette device, within about 5 mm
to about 1 mm, and then the samples can be precisely located in a
predetermined location in space with respect to the station to
within about 0.5 mm to 0.1 mm or better.
[0086] Alternatively, the components of the micro position system
60 can be reversed, as between the robot 3 and the station 4. For
example, the locating fixture 61, or projections can extend upward
from the top 64 of the working level surface 22 proximate the
station 4 and the device 8, and the cooperating locating fixture
62, or depressions, can be formed in an undersurface 63 of the
robot body 40. In this embodiment, the robot 3 could lower itself
onto the projections 61 such that the projections 61 fit within the
depressions 62, or alternatively, a portion of the working surface
could raise up, such as for example a piston actuated platform, to
lift the robot or plate, thereby engaging the micro positioning
system. In addition, other precision positioning devices can be
used, such as, for example, G.P.S. positioning, laser and light
positioning, acoustic positioning, magnetic positioning, etc.
[0087] In addition, the micro positioning system 60 can be adapted
based on the particular system and robot design for a given
application. For example, in an embodiment (not shown) having a
robot in a channel, or slot, design, the micro positioning system
could comprise one or more bars or rods that extend outward and
cooperate with, for example, the side walls of the channel or
slot.
[0088] As shown in FIG. 12, the system can include an
identification and communications system 70. Preferably, because it
is desirable to keep the robots 3 simple and easy to manufacture,
the robots 3 are constructed such that they do not require constant
communications with the devices 8 or the central controller 30.
However, in this type of embodiment, the robots 3 preferably
provide for communications when they are docked at a station 4.
[0089] Preferably, when the robot 3 reaches its final destination
(e.g., by detection of the last entry in the navigation
instructions or binary list or by detection of a station) an
attempt can be made to identify the robot 3 and to determine
whether the robot 3 is at the correct location 4. Any known
identification and communications technology can be used to
identify the robot 3 and to determine if it at the correct location
4, including, for example, by directional infrared link, short
range RF, RFID, by electrical contact through the indexing feet 61,
1-D or 2-D bar code, etc.
[0090] An exemplary identification and communications system is
shown in FIG. 12. As shown, the identification and communications
system 70 is disposed between the robot 3 and the station 4 and/or
device 8. As shown, the robot 3 includes an integrated circuit 71
having processing and memory functions disposed therein. The
integrated circuit 71 can control an indicator device 72 disposed
on an outer surface of the robot body 40. The station 4 or device 8
can include a sensor device 73 and an integrated circuit 74 having
processing and memory functions disposed therein. The indicator
device 72 illuminates or activates the sensor device 73.
[0091] Once the sensor device 73 has been activated, the
microprocessor 31 at the central controller 30, or a similar system
at the station 4, processes and compares the signal form the
indicator device 72 to stored robot identification data stored in a
memory. As shown, the integrated circuit 74 is coupled to a gain
stage 75 through an optional filtering device 76. Gain is applied
to the output of the sensor device 73 and the output from the gain
stage 75 is provided to a comparator 77 which compares the received
identification data with stored identification data. The results of
the comparison are provided to a microprocessor 78 which determines
if the robot 3 is at the correct location 4, and based on the
comparison activates the device 8 or sends a new set of
navigational instructions to the robot 3.
[0092] Several exemplary examples that can comprise the indicator
device 72 and the sensor device 73 described herein above, include,
for example, an LED indicator and a light sensor; an infrared
indicator and infrared sensor; a communications port provided at
both the robot and the station or device for establishing one of a
wired and a wireless connection between the robot and the station;
an imager/camera for capturing a graphical representation; an RFID
tag having a transporter and a reader; an optical recognition
system; a magnetic storage strip and reader, 1-D or 2-D bar code,
an integrated chip or embedded memory chip, a key and corresponding
slot, etc. Preferably, the indicating device 72 is located on the
robot 3 and the sensing device 73 is on located at the station 4.
An exemplary identification system that can be used with the
present invention is the Infrared Proximity Detector Kit (IRPD)
manufactured by LYNXMOTION, of Pekin, Ill. However, the location of
the indicating device and a sensing device can be interchangeable
as between the robot and station.
[0093] Once the identification of the robot 3 has been successfully
completed, and it is determined that the robot 3 is at the correct
location 4, the device 8 is activated and begins to interact with
the robot 3 thereby performing some function or manipulation on the
sample 9 contained in the sample holding device 13. For example, in
an exemplary embodiment involving biometric samples contained in a
96-well plate, the robot is grossly positioned near, for example a
pipette device (e.g., within about 5 mm to about 1 mm) and then
precisely located in a predetermined location in space with respect
to the station 4 (e.g., within about 0.5 to about 0.1 mm or
better), thereby virtually assuring that the sample 9 will be
substantially centered or aligned with respect to the device 8.
Under these conditions, the device 8 is activated and is free to
perform some function on the sample 9, such as transferring,
loading, unloading, monitoring, reading, accessing, etc. The
devices themselves can communicate with each other and a central
control system by standard networking technologies, such as TCP/IP.
Note that the tolerance scale of the macro positioning system and
micro positioning system is scalable with the rest of the system.
For example, in a micro-robotic system, the tolerances may be even
smaller, thereby keeping in scale with the rest of the robotic
system.
[0094] Identification data can be stored on-board the robot 3 and
transmitted to some type of sensor 73 on the station 4, or
alternatively, the robot 3 can be a dumb device having some
identifying feature that is read by the station and then compared
to a stored identification characteristic in a memory of the
station or a central database controlled by the central controller
30.
[0095] Optionally, the robot 3 of the present invention can be
equipped with a passive feedback mechanism (not shown) which, for
example, could be provided as an indicator or combination of
indicators that provide, on a near real-time basis, an indication
to an operator that the system is operating and functioning
properly. For example, the feedback system might detect if a robot
stops moving along the pathway, if a robot is moving the wrong way
on the pathway, if a robot is lost, if a robot is not being
positioned properly with respect to a device, etc.
[0096] In addition, the system can include position indicators (not
shown) that show the location in the system of the robots.
Preferably, the indicators are visible and/or audible, such as, an
indicator lamp (e.g., a light emitting diode (LED)) that lights,
for example, when a robot is lost, and an aural indicator via a
speaker, such as a beep or other tone, that sounds periodically
until the robot or an operator corrects the robot and puts it back
on the correct pathway. Alternatively, a display device, such as a
video display or an LCD, can be provided for viewing or displaying
a status or condition of the system.
[0097] Referring back to FIG. 1, the system 1 includes one or more
devices 8 for interacting with the robots 3. Devices 8 are
components of the system that are preferably fixed in location, as
shown in FIG. 12. Alternatively, a device 8 can be mounted on a
robot 3 wherein the device 8 can be transported around the system 1
to interact with, for example a sample, or cargo, storage devices.
Devices 8 can perform various functions, such as, for example,
transferring liquid from one plate to another (with pipettes or
transfer pins), reading some attribute of the sample like
fluorescence or optical density, manipulating samples in some other
way, etc. In all sample carrying robot embodiments discussed
herein, these devices 8 are located at the destinations 4 that the
robots 4 carry their samples 9 to.
[0098] Devices 8 access plates 13 holding samples 9 either in place
on the robot, or by transferring them to the device by a simple
pick and place arm (not shown) built with, for example, PWM servos
or Nitinol thermally activated memory metals. This arm could be
fixed relative to the device, or alternatively, the arm can be
mounted on the robot itself Optional lids on the plates (not shown)
could be manipulated by the same pick and place arm, or by an arm
on the robot itself, which would hold the lid out of the way during
access.
[0099] FIGS. 13A and 13B show exemplary devices 8 for an exemplary
liquid handling system in accordance with the present invention.
One or more devices 8 can be positioned at a station 4 for
interaction with a sample 9 carried on the robot 3. Preferably
there is one device 8 at each station 8, as shown in FIGS. 1 and
12, and the device 8 is adapted for the precision interaction with
the robot 3.
[0100] For example, in an exemplary liquid handling system, an
exemplary device 8 can be any standard device, including, for
example, a plate washer device, a pipette device, a plate reader
device, etc. The device 8 interacts by manipulating or performing
some function on the samples 9. The device 8 can include any device
for interacting with a sample 9 depending on the application. Each
device 8 are designed for precision interaction with the samples 9
carried on the robot 3.
[0101] FIG. 13A shows an exemplary pipette device 80. As shown, the
pipette's device 80 includes a plurality of pipettes having a body
81, a manifold 82, an actuator mechanism 83, and a tip 84. The
pipette device 80 is activated once the robot 3 has been properly
positioned and identified. The device 8 then interacts with the
samples 9 to perform a preselected function or operation on the
samples 9, such as filling, taking a sample, analyzing a sample,
etc.
[0102] FIG. 13B shows an exemplary plate washer device 85. As
shown, the plate washer device 85 includes a manifold 86 having a
plurality of nozzles 87 extending therefrom. A washing agent (not
shown) is sprayed from the nozzles 87 into the wells 52 of the
sample holding device 13 to clean it. After the wash cycle is
complete, the nozzles 87 can pull the wash agent from the wells 52
of the sample holding device 13.
[0103] The sample positioning system 1 of the present invention is
preferably fast enough that significant plate 13 and sample 9
storage is required to feed the process and to incubate samples
during the processes. Several potential means are available for
this.
[0104] As shown in FIG. 1 and FIG. 14, the system 1 can also
include a storage system 90 for the storage of various cargo and
samples 9. The storage system can be oriented horizontally (e.g.,
along the X-axis), as shown in FIG. 1, or alternatively, the
storage system can be oriented vertically (e.g., along the Y-axis),
as shown in FIG. 14.
[0105] As shown in FIG. 14, samples are stored in one or more
storage devices 91 located on levels which are preferably
positioned close together one on top of the other (e.g.,
vertically). The storage devices 91 can comprise any standard
storage mechanism, such as for example shelves, racks, bins,
containers, etc. These shelves 91 are supported by a support
structure 96.
[0106] The support structure 96 can also supports a track 92. A
robot can run on this track 92 both horizontally, as shown by robot
3a, and vertically, as shown by robot 3b. As shown, the robot has a
gimbaled platform 93 for the plate 13a, 13b to rest upon. Robot 3a
shows the gimbal 93 in the horizontal position, while robot 3b
shows the gimbal in the vertical position. In the vertical case,
the plate 13b is still level and can be slid into or out of a shelf
91 through an opening 94 formed in the base 95 of the robot 3.
[0107] The robot 3 can be made to run vertically by several means.
For example, if the robots 3 are very small, simple magnetic
attraction to the track 92 will normally be sufficient. Larger
robots may require a track gripping mechanism, such as for example,
a cog rail, pins, rods, hooks, etc. for gripping the track.
[0108] In an alternative embodiment (not shown), the storage
locations can be arranged in shelves with tracks running between
shelves on each level. The robots get to the desired level for drop
off or pick up by navigating up ramps, such as for example a spiral
ramp. Each turn of the spiral raises the track to the next shelf.
At each turn a standard forking intersection is reached, which the
robot navigates in the usual style. Thus, storage locations are
like any other device. Plates or samples can be loaded or unloaded
from the robots by, for example, an arm built into either the robot
or the storage location which sweeps the plate from the robot
storage location, or vice versa. This arm does not need
proportional control and could be actuated by Nitinol or solenoid.
Similar downward traveling ramps can also be provided.
[0109] The robotic positioning system of the present invention can
also include an error recovery system. For example, all stations,
or destinations, can be marked with a separate sensor. When a robot
arrives at what it thinks is its destination, it announces itself
and its sample ID to the station. The station can be told to expect
a certain list of samples. If the station is expecting this sample,
in addition to performing its operation, it gets navigation
instructions for the robot's next task from central control and
passes these to the robot. If it is not expecting this sample, it
checks with central control and gets new navigation instructions
for the robot which lead it from wherever it ended up in error to
the correct location in the system. It gives the robot these
instructions and sends it on its way.
[0110] If communication fails or the robot is not identified for
some other reason, the robot assumes that it is lost and can follow
its emergency instructions. These instructions can, for example, be
a simple set of instructions that direct the robot to stop at all
future intersections to see if they are devices which it can
communicate with. If the intersection has no device, it makes, for
example, a left turn and continues to the next intersection. As
soon as it finds any device with which it can communicate, that
device requests new navigation instructions from a central control
on behalf of the lost robot. Alternatively, if the robot is not
identified, it can activate an indicator and an operator could be
notified to place the robot back onto the correct pathway.
[0111] FIG. 15 is a flowchart showing an exemplary robot
identification process with error correction. As shown in FIG. 15,
the internal on-board computer indicates that the robot is at a
station, or destination, at step 200. The robot then attempts to
establish. communications with the station, at step 205. The robot
determines whether a communications link has been successfully
established at step 210. If it is determined, at step 210, that no
communications link is established, then the robot executes a
default set of navigational instructions and turns right, at step
215. The robot then travels forward at step 220, to the next
station/intersection is detected, at which time the robot again
attempts, at step 205, to establish a communications link with the
station.
[0112] If it is determined that a successful communications link
was established, at step 210, then the robot transmits its own
identification to the station, at step 225 for identification. The
robot can also transmit an identification code of the cargo or
sample that it is carrying to the station, at step 225. The station
then determines whether the identifications of the robot and/or the
sample match an expected identification code, at step 230. The
stored identification codes can be stored in a memory at the
station or in a central database.
[0113] If the identification codes do not match at step 230, then
the station can get new navigational instructions from the central
controller, at step 235 and passes/loads these new instructions
into the robot and the robot moves forward, at step 240, in order
to attempt to correct the location of the robot. The robot
continues forward until its on-board navigational system again
indicates that it is at a station, at step 200. If the
identification codes do match at step 230, then the station
interacts with the robot, at step 245, such as performing some
action or functions on the cargo, or samples. Once the station has
completed its interaction with the robot at step 245, the process
proceeds to step 235, 240 and then 200 as described herein
above.
[0114] The system of the present invention can include a collision
avoidance system 165. The collision avoidance system 165 acts to
prevent the robots 3 from colliding with one another as they move
around the pathways 5. The collision avoidance system 165 can be
disposed between individual robots 3, or alternatively, it can be
disposed between the robots and a position along the pathways 5,
such as proximate an intersection 10 and/or a station 4.
[0115] The collision avoidance system 165 can include an indicator
or transmitter device 166, a sensor or receiver device 167, and an
integrated circuit 168 having processing and memory functions
disposed therein. The indicator 166 and sensor 167 can be any
standard type of compatible indicator device and sensor device,
including, for example, an optical system, an acoustic system, an
electromagnetic system, an electrical system, a RF system, etc.
Although not required, it is preferred that the collision avoidance
be handled locally by the individual robots, thereby not requiring
a central control management for the tracking of detailed position
and prevention of collisions.
[0116] FIGS. 16A, 16B, 17A and 17B show exemplary collision
avoidance systems 165 designed to prevent one robot from colliding
with another robot. The collision avoidance systems 165 preferably
at least accounts for potential collisions at merging pathways in
the system and for rear-end collisions.
[0117] For example, FIGS. 16A and 16B show several exemplary
embodiments of collision avoidance systems 165a for merging
pathways. In a first track merger collision avoidance system shown
in FIG. 16A, each robot can have one or more indicator device 166,
such as, for example, an IR LEDs, positioned on the right side of
the robot body 40 pointing out to the right (166a and 166b of FIG.
16A). Each robot can also have a detector device 167, such as, for
example, an IR sensor, positioned on the left side of the robot
body 40 pointing to left (167a and 167b of FIG. 16A). If a robot's
left looking sensor 167a, 167b is activated, it assumes that
another robot is approaching an intersection 10. In this
embodiment, the detecting robot slows or stops until the signal
clears, thus allowing the robot on its left side to have the right
of way. As shown in FIG. 16A, robot 3c is on pathway 5a on the
right and Robot 3d is on pathway 5b on the left. Robot 3c stops, or
slows, because its sensor 167b sees robot 3d's indicator 166a.
Parallel paths with traffic moving in opposite directions do not
cause a problem because the robots pass either indicator to
indicator or sensor to sensor, causing no detection. Problems with
parallel paths moving in the same direction can be avoided by
providing a barrier (not shown) to block the sensor from the
indicator, by separating the parallel pathways by a sufficient
distance to avoid sensing of the indicator, or alternatively, the
robot on the left will stop or slow momentarily until the robot on
the right travels down its pathways and is no longer detected.
[0118] FIG. 16B shows another track merger collision avoidance
system. As shown in FIG. 16B, the collision avoidance system 165
can include, for example, electronic devices 169, 170 disposed
along the left side of one or more of the pathway 5a, 5b. As shown,
the electronic devices 169, 170 can include, for example, an IR LED
indicator 169 and a receiver 170 pair disposed across path 5b to
detect the presence of robot 3d. Robot 3d is detected by the robot
3d blocking or interrupting, for example a light path 171 between
indicator 169 and sensor 170. When a robot 3d is detected on the
left fork 5b as shown, the electronics can illuminate an indicator
172, such as an LED, positioned along the right fork 5a pointing
toward any oncoming robots, such as robot 3c shown. If a robot does
come down that right path 5a, a rear-end collision detection sensor
173 disposed on the front of the robot 3c can be activated causing
robot 3c to stop, thinking it is about to hit a robot from behind.
Robot 3c remains stopped until indicator 172 is turned off, which
only happens when the other robot 3d clears the left fork 5b, as
indicated by light path 171 being re-established between indicator
169 and sensor 170.
[0119] An exemplary rear-end collision avoidance system 165b is
shown in FIG. 17A and 17B. As shown in the exemplary system of FIG.
17A and 17B, rear-end collision avoidance can be accomplished by
positioning an indicator device 175, such as an IR LED, on the rear
of each robot body 40 and positioning one or more sensor devices
176a, 176b, such as IR sensors, on the front of each robot body 40.
This embodiment can provide multiple distance warnings.
[0120] In FIG. 17A the robot is at medium distance and sensor 176a
can detect LED 175 through a pinhole opening 177, as illustrated by
beam line 178a. Robot 3d slows down in response to this signal. In
FIG. 17B, robot 3d is at close range allowing sensor 176b to detect
LED 704. In response to this signal, robot 3d stops, or slows
further. Multiple levels and even analog ranges are possible to
measure by extending this system. In addition, this system can also
be used by the track itself, for merging collision avoidance, or
alternatively by a device along the track to stop a robot.
[0121] FIG. 18 is flowchart combining the exemplary merging
pathways collision avoidance system of FIGS. 16A and 16B and the
exemplary rear-end collision avoidance system of FIGS. 17A and 17B.
As shown in FIG. 18, the electronics check the sensor input bits,
at step 300. At step 305 it is determined whether or not the near
sensor has been activated. If it is determined, at step 305, that
the near sensor has been activated, then the electronics set the
speed to stop, at step 310. After a predetermined period of time,
the electronics again check the sensor input bits, at step 300.
[0122] If it is determined that the near sensor has not been
activated, then the electronics proceed to step 315, where it is
determined whether or not the far sensor has been activated. If it
is determined, at step 315, that the far sensor has been activated,
then the electronics set the speed to slow, at step 320. After a
predetermined period of time, the electronics again check the
sensor input bits, at step 300.
[0123] If it is determined, at step 315, that the far sensor has
not been activated, then the electronics proceed to step 325, where
it is determined whether or not the side sensor has been activated.
If it is determined, at step 325, that the side sensor has been
activated, then the electronics set the speed to stop, at step 330.
After a predetermined period of time, the electronics again check
the sensor input bits, at step 300.
[0124] If it is determined, at step 325, that the far sensor has
not been activated, then the electronics proceed to step 335, where
the electronics set the speed of the robot to fast. After a
predetermined period of time, the electronics again check the
sensor input bits, at step 300.
[0125] The grid-type track system, described herein above with
reference to FIG. 3, can have a different overall collision
avoidance system (not shown) then the embodiments described herein
above. The rear-end avoidance system can be identical to the system
describe herein above with reference to FIGS. 17A and 17B, but
front-end and side collisions can be handled differently.
[0126] FIG. 19 shows an exemplary collision avoidance system for
use with a grid-type track system 6c. As shown in FIG. 19, each
robot 3 can be configured with one or more computer controlled
indicators 180, such as, for example, colors of LEDs, positioned on
all four sides of the robot body 40, as well as one or more sensors
181 that can distinguish between these colors. Preferably, the
sensors 181 are aligned such that they cannot see further than
about one grid block, or alternatively, the indicators can only
project out than about one grid block. In addition, preferably two
indicators and two sensors are disposed on each side and are
located at opposite ends of each side. A robot's "front" 183, as
used here, always means the leading side in the direction of
travel.
[0127] For example, if a robot 3f is heading West, as indicated by
directional arrow 182, the West side is the front 183. Robots
control their lights such that the "front" light is always a first
color, for example red, and the "side" lights are a second color,
for example green. The "back" lights are preferably a third color
and a separate system, as described in the rear-end collision
avoidance section and shown in FIGS. 17A and 17B.
[0128] The collision avoidance technique used by all robots is
preferably designed having a protocol that gives right-of-way to
predetermined directions of traffic, such as for example, north and
west bound robots. For example, the following rules can be
used:
[0129] If moving North and see red, go straight;
[0130] If moving South and see red, turn West for one block;
[0131] If moving West and see red, go straight;
[0132] If moving East and see red, turn North for one block;
and
[0133] If see green, stop until green is gone.
[0134] Using the above exemplary protocol for the robots 3e, 3f,
and 3g of FIG. 19 would yield the following results. Robot 3e,
which is shown traveling East, would see the red lights of robot
3f, which is shown traveling West. Accordingly, robot 3e would turn
north for one block. Robot 3f would also see the red lights of
robot 3e and since it is traveling West, robot 3f would continue to
travel straight (e.g., West). Robot 3g, which is shown traveling
North, would see the green lights of robot 3f, which is again
traveling West. Accordingly, robot 3g would stop until it no longer
sensed the green lights of robot 3f.
[0135] FIG. 20 is a flowchart of the exemplary side and front
collision avoidance system of FIG. 19. As shown in FIG. 20, the
electronics check all sensor input bits, at step 400. At step 405
it is determined whether or not the sensor detects the color green
in front. If it is determined, at step 405, that the color green
has been detected, then the electronics set the speed to stop, at
step 410. After a predetermined period of time, the electronics
again check all sensor input bits, at step 400.
[0136] If it is determined that the color green has not been
detected, then the electronics proceed to step 415, where it is
determined whether or not the robot is heading South. If it is
determined, at step 415, that the robot is heading South, then it
is determined whether or not the sensor detects the color red in
front, at step 420. If it is determined, at step 420, that the
color red has been detected, then the robot turns West for one
block, at step 425. After a predetermined period of time, the
electronics again check all sensor input bits, at step 400.
[0137] If it is determined, at step 420, that the color red has not
been detected, then the electronics set the robot speed to fast and
continues the robot straight (e.g., in the same direction that it
was traveling), at step 450. The robot continues to travel straight
for a predetermined period of time, and then the electronics again
check all sensors at step 400.
[0138] If it is determined, at step 415, that the robot is not
heading South, then the electronics proceed to step 430, where it
is determined whether or not the robot is heading East. If it is
determined, at step 430, that the robot is heading East, then it is
determined whether or not the sensor detects the color red in
front, at step 435. If it is determined, at step 435, that the
color red has been detected, then the robot turns North for one
block, at step 440. After a predetermined period of time, the
electronics again check all sensor input bits, at step 400.
[0139] If it is determined, at step 435, that the color red has not
been detected, then the electronics set the robot speed to fast and
continues the robot straight (e.g., in the same direction that it
was traveling), at step 450. The robot continues to travel straight
for a predetermined period of time, and then the electronics again
check all sensors at step 400.
[0140] If it is determined, at step 430, that the robot is not
heading East, then the electronics proceed to step 450, where the
electronics set the robot speed to fast and continues the robot
straight (e.g., in the same direction that it was traveling). After
a predetermined period of time, the electronics again check all
sensor input bits, at step 400.
[0141] The present invention comprising a system and method of
accurately positioning a sample to be worked on or manipulated
using a macro positioning subsystem and a micro positioning
subsystem in a robotic system, has significant value in those
situations where there are compelling needs for the gross movement
and locating of samples between various stations coupled with the
need for precision locating of the sample at each station with
respect to a device at each station.
[0142] Although illustrated and described herein with reference to
certain specific embodiments, it will be understood by those
skilled in the art that the invention is not limited to the
embodiments specifically disclosed herein. Those skilled in the art
also will appreciate that many other variations of the specific
embodiments described herein are intended to be within the scope of
the invention as defined by the following claims.
* * * * *