U.S. patent application number 15/310569 was filed with the patent office on 2017-03-23 for system and method for measuring finger movements.
This patent application is currently assigned to UNIST (ULSAN NATIONAL INSTITUTE OF SCIENCE AND TECHNOLOGY). The applicant listed for this patent is UNIST (ULSAN NATIONAL INSTITUTE OF SCIENCE AND TECHNOLOGY). Invention is credited to Joonbum BAE, Jeongsoo LEE, Yeongyu PARK.
Application Number | 20170079560 15/310569 |
Document ID | / |
Family ID | 54480164 |
Filed Date | 2017-03-23 |
United States Patent
Application |
20170079560 |
Kind Code |
A1 |
BAE; Joonbum ; et
al. |
March 23, 2017 |
SYSTEM AND METHOD FOR MEASURING FINGER MOVEMENTS
Abstract
A system for and a method of measuring motions of a thumb and
fingers of a user who wears a glove are provided. The method
includes attaching first ends of first and second flexible wires to
positions of the glove respectively corresponding to middle and
proximal phalanxes of each finger, and connecting second ends of
the first and second flexible wires to a sensing module so that the
first and second flexible wires can move forward and backward while
maintaining tension thereof in accordance with a motion of the
finger. The method further includes, by the sensing module,
measuring moved distances of the first and second flexible wires,
such that rotary angles at corresponding joints in the thumb and
fingers are calculated based on the measured moved distances.
Inventors: |
BAE; Joonbum; (Ulsan,
KR) ; PARK; Yeongyu; (Incheon, KR) ; LEE;
Jeongsoo; (Goyang-si, Gyeonggi-do, KR) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
UNIST (ULSAN NATIONAL INSTITUTE OF SCIENCE AND TECHNOLOGY) |
Ulsan |
|
KR |
|
|
Assignee: |
UNIST (ULSAN NATIONAL INSTITUTE OF
SCIENCE AND TECHNOLOGY)
Ulsan
KR
|
Family ID: |
54480164 |
Appl. No.: |
15/310569 |
Filed: |
April 30, 2015 |
PCT Filed: |
April 30, 2015 |
PCT NO: |
PCT/KR2015/004398 |
371 Date: |
November 11, 2016 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
A61B 5/1121 20130101;
A61B 5/1114 20130101; A61B 5/1071 20130101; A61B 5/11 20130101;
A61B 5/6806 20130101 |
International
Class: |
A61B 5/11 20060101
A61B005/11; A61B 5/107 20060101 A61B005/107 |
Foreign Application Data
Date |
Code |
Application Number |
May 12, 2014 |
KR |
10-2014-0056528 |
Claims
1. A system (100) for measuring motions of a thumb and fingers, the
system comprising: a glove (10) which is worn by a user; first and
second flexible wires (20) which are movable in accordance with
motions of a thumb and fingers, comprise first ends attached to the
glove and have predetermined lengths; and a sensing module (30)
which comprises first and second linear potentiometers respectively
connecting with second ends of the first and second flexible wires
and comprising elastic members for maintaining tension of the
flexible wires, wherein the first end of the first flexible wire is
attached to a position on the glove corresponding to a position
between a first joint and a second joint of a finger, and the first
end of the second flexible wire is attached to a position on the
glove corresponding to a position between the second joint and a
third joint of the finger, wherein angles at the first and second
joints are calculated based on changed distances of the attached
positions measured by the flexible wires and the linear
potentiometers of the sensing module in accordance with a motion of
the finger.
2. The system according to claim 1, wherein the first and second
flexible wires and the sensing module are provided in each of a
thumb and fingers.
3. The system according to claim 1, wherein the sensing module is
placed on a position of the glove corresponding to a back of a
hand.
4. The system according to claim 1, wherein the elastic member of
the sensing module comprises a linear spring.
5. The system according to claim 1, wherein the first, second and
third joints respectively correspond to a proximal interphalangeal
(PIP) joint, a metacarpophalangeal (MCP) joint and a distal
interphalangeal (DIP) joint.
6. A method of measuring motions of a thumb and fingers of a user
who wears a glove, the method comprising: attaching first ends of
first and second flexible wires to positions of the glove
respectively corresponding to middle and proximal phalanxes of each
finger; connecting second ends of the first and second flexible
wires to a sensing module so that the first and second flexible
wires can move forward and backward while maintaining tension
thereof in accordance with a motion of the finger; and by the
sensing module, measuring moved distances of the first and second
flexible wires, wherein rotary angles at corresponding joints in
the thumb and fingers are calculated based on the measured moved
distances.
7. The method according to claim 6, wherein the sensing module is
placed on a position of the glove corresponding to a back of a
hand.
8. The method according to claim 6, wherein each tension of the
first and second flexible wires is constantly maintained by an
elastic member provided in the sensing module.
9. The method according to claim 8, wherein the elastic member
comprises a linear spring.
10. The method according to claim 6, wherein the moved distances of
the first and second flexible wires are respectively measured by
first and second linear potentiometers provided in the sensing
module.
11. The method according to claim 6, wherein the sensing module
comprises a frame made of nylon and by rapid prototyping
technology.
12. The system according to claim 2, wherein the sensing module is
placed on a position of the glove corresponding to a back of a
hand.
13. The system according to claim 2, wherein the elastic member of
the sensing module comprises a linear spring.
14. The system according to claim 2, wherein the first, second and
third joints respectively correspond to a proximal interphalangeal
(PIP) joint, a metacarpophalangeal (MCP) joint and a distal
interphalangeal(DIP) joint.
15. The method according to claim 7, wherein the moved distances of
the first and second flexible wires are respectively measured by
first and second linear potentiometers provided in the sensing
module.
16. The method according to claim 8, wherein the moved distances of
the first and second flexible wires are respectively measured by
first and second linear potentiometers provided in the sensing
module.
17. The method according to claim 9, wherein the moved distances of
the first and second flexible wires are respectively measured by
first and second linear potentiometers provided in the sensing
module.
Description
TECHNICAL FIELD
[0001] The present invention relates to a system and method of
measuring motions of a thumb and fingers, and more particularly to
a system and method of measuring motions of a thumb and fingers,
which informs relation between positions varied depending on the
motions of a thumb and fingers.
BACKGROUND ART
[0002] A hand is one of abundant sources in terms of tactile
sensing, and it is impossible to achieve elaborate and complicated
manipulation without the hand. To develop a wearable system for the
hand, an unconstrained hand motion has to be previously analyzed.
Accordingly, extensive researches about a simple system for
measuring motions of a thumb and fingers have been carried out.
[0003] First, a similarity approach using an optical linear encoder
(OLE) has been tried, but the encoder attached to a thumb and
fingers and a thick and wide wire cable for the optical encoder may
interfere with a natural motion of the thumb and fingers.
[0004] Further, a 3D magnetic position sensor has been used in
measuring angles at joints of a thumb and fingers, and thus
three-dimensionally measured motions of the thumb and fingers.
However, required peripheral devices may obstruct the unconstrained
hand motion.
[0005] In addition, an optical fiber sensor has been also used in
measuring the angles. The optical fiber sensor is mounted to a
glove for the purpose of easy wearing, but the optical sensor has
to be carefully bent to measure the angles at the joints. Besides,
the mobility of the optical sensor is extremely limited by required
peripheral devices such as a laser diode and an optical power
system.
[0006] By the way, a flexible resistor is commercially available
and shows good performance with respect resolution and
repeatability. However, the flexible resistor is economically
inefficient and difficult to combine with another system such as a
hand exoskeleton system.
[0007] Like this, the optical encoder, the magnetic position
sensor, the optical fiber sensor, the flexible resistor, and the
like have been used, but not regarded as a compact and simple
measuring system--capable of measuring unconstrained motions of a
thumb and fingers--due to a limited space of a hand.
DISCLOSURE
Technical Problem
[0008] The present invention is conceived to solve the foregoing
problems, and an aspect of the present invention is to provide a
system for measuring motions of a thumb and fingers, which can
relatively easily measure angles at joints of a thumb and fingers
within a limited space of the thumb and fingers, and is lightweight
and compact enough not to hinder a natural motion of a hand, and a
method of using the same.
Technical Solution
[0009] In accordance with one aspect of the present invention,
there is provided a system for measuring motions of a thumb and
fingers, the system including: a glove which is worn by a user;
first and second flexible wires which are movable in accordance
with motions of a thumb and fingers, include first ends attached to
the glove and have predetermined lengths; and a sensing module
which includes first and second linear potentiometers respectively
connecting with second ends of the first and second flexible wires
and including elastic members for maintaining tension of the
flexible wires, wherein the first end of the first flexible wire is
attached to a position on the glove corresponding to a position
between a first joint and a second joint of a finger, and the first
end of the second flexible wire is attached to a position on the
glove corresponding to a position between the second joint and a
third joint of the finger, wherein angles at the first and second
joints are calculated based on changed distances of the attached
positions measured by the flexible wires and the linear
potentiometers of the sensing module in accordance with a motion of
the finger.
[0010] The first and second flexible wires and the sensing module
may be provided in each of a thumb and fingers.
[0011] The sensing module may be placed on a position of the glove
corresponding to a back of a hand.
[0012] The elastic member of the sensing module may include a
linear spring, and the first, second and third joints respectively
correspond to a proximal interphalangeal (PIP) joint, a
metacarpophalangeal (MCP) joint and a distal interphalangeal(DIP)
joint.
[0013] In accordance with one aspect of the present invention,
there is provided a method of measuring motions of a thumb and
fingers of a user who wears a glove, the method including:
attaching first ends of first and second flexible wires to
positions of the glove respectively corresponding to middle and
proximal phalanxes of each finger; connecting second ends of the
first and second flexible wires to a sensing module so that the
first and second flexible wires can move forward and backward while
maintaining tension thereof in accordance with a motion of the
finger; and by the sensing module, measuring moved distances of the
first and second flexible wires, wherein rotary angles at
corresponding joints in the thumb and fingers are calculated based
on the measured moved distances.
[0014] The sensing module may be placed on a position of the glove
corresponding to a back of a hand.
[0015] Each tension of the first and second flexible wires is
constantly maintained by an elastic member provided in the sensing
module, and the elastic member may include a linear spring.
[0016] The moved distances of the first and second flexible wires
may be respectively measured by first and second linear
potentiometers provided in the sensing module.
[0017] The sensing module may include a frame made of nylon and by
rapid prototyping technology, but there are no limits to the
material and technology as long as they have similar effects.
Advantageous Effects
[0018] In the system and method of measuring flexion/extension
motions of thumb and finger motion according to an embodiment of
the present invention, it is possible to relatively easily measure
angles at joints of a thumb and fingers within a limited space of
the thumb and fingers, and it is lightweight and compact enough not
to hinder a natural motion of a hand.
DESCRIPTION OF DRAWINGS
[0019] FIG. 1 is an anatomical schematic view of a hand,
[0020] FIG. 2 is a cross-section view of a thumb and fingers,
[0021] FIG. 3 is a conception view of a system according to the
present invention,
[0022] FIG. 4 illustrates a system designed according to the
present invention,
[0023] FIG. 5 illustrates a system designed according to the
present invention,
[0024] FIG. 6 illustrates a test device,
[0025] FIG. 7 is a graph of showing a relationship between a DIP
joint and a PIP joint,
[0026] FIG. 8 illustrates a sensing module designed according to an
embodiment of the present invention,
[0027] FIG. 9 is a photograph of a wearable sensing glove according
to an embodiment of the present invention, and
[0028] FIG. 10 shows a program interface according to an embodiment
of the present invention.
REFERENCE NUMERALS
[0029] 100 System for measuring motions of a finger and thumbs
[0030] 10 user wearable glove 20 first and second flexible
wires
[0031] 30 sensing module 40 cylindrical guide
BEST MODE
[0032] Embodiments of the present invention will be described in
detail with reference to the accompanying drawings. Prior to the
description, it will be appreciated that terms and words used in
the following description and claims have to be interpreted by not
the limited meaning of the typical or dictionary definition, but
the meaning and concept corresponding to the technical idea of the
present invention on the assumption that the inventor can properly
define the concept of the terms in order to describe his/her own
invention in the best way.
[0033] Further, embodiments described in this specification and
elements shown in the drawings are nothing but preferable examples,
and do not represent the entirety of the present technical idea.
Accordingly, it will be appreciated that they may be replaced by
various equivalents and modifications on the filing date of the
present invention. Prior
[0034] The present invention proposes a system for measuring
motions of a thumb and fingers, which employs a linear
potentiometer, a flexible wire and a linear spring. The flexible
wires are attached to backsides of a thumb and fingers. As the
flexible wire moves corresponding to motions of a thumb and
fingers, angles at joints are calculated by measuring change in the
length of the flexible wire. The linear potentiometer, which has
the linear spring for maintaining tension of the wire, is used in
measuring the angles at the joints. A proximal interphalangeal
(PIP) motion is dependent on a distal interphalangeal (DIP) joint,
and therefore only two linear potentiometers are applied to each of
the thumb and fingers. This compact sensing module with ten linear
potentiometers and springs is attached to a glove. By just wearing
such a glove, the motions of the thumb and fingers are easily
measured by an easy program interface.
[0035] Skeleton Structure Of Hand
[0036] A hand consists of bones, muscles and ligaments of joints,
which are complicatedly combined and determine a direction and
range of a hand motion. To accurately measure motions of a thumb
and fingers, it is required to understand an anatomical structure
of a hand. Below, the anatomical structure of the hand will be
described in brief.
[0037] The hand motion is carried out by 19 bones, 19 joints and 29
muscles. As shown in FIG. 1, each of the fingers except the thumb
includes three bones, i.e. a distal phalanx, a middle phalanx and a
proximal phalanx and three joints, i.e. a proximal interphalangeal
(PIP) joint, a metacarpophalangeal (MCP) joint and a distal
interphalangeal (DIP) joint. The thumb includes two bones, i.e. a
distal phalanx and a proximal phalanx, and two joints, i.e. an
interphalangeal (IP) joint, and an MCP joint. Metacarpal phalanx
bones meet a wrist at carpometacarpal (CMC) joints. The IP joint
including the PIP and DIP joints has one degree of freedom for
flexion/extension motions, and the MCP joint has two degrees of
freedom for flexion/extension and abduction/adduction motions.
[0038] To control an object with a hand, the motion of
flexion/extension is typically more required than the motion of
abduction/adduction. Accordingly, there is a great need of a system
for measuring flexion/extension motions of a thumb and fingers
without hindering natural motions of the thumb and fingers.
[0039] System Elements
[0040] FIG. 2 shows a cross-section of a finger for a
flexion/extension motion. In each of the fingers, the lengths
C.sub.1, C.sub.2 and C.sub.3 of the phalanxes are previously
measured. When angles of .theta..sub.1, .theta..sub.2 and
.theta..sub.3 between joints are measured, a tip position of the
finger is expressed as follows.
I=C.sub.1 cos(.theta..sub.1)+C.sub.2 cos(.theta..sub.2)+C.sub.3
cos(.theta..sub.3) [Equation 1]
y=C.sub.1 sin(.theta..sub.1)+C.sub.2 sin(.theta..sub.2)+C.sub.3
sin(.theta..sub.3) [Equation 2]
[0041] As shown in the Equations 1 and 2, only three angles at the
joints are needed to describe the flexion/extension motion of each
finger. However, a limited space of the thumb makes it difficult to
measure the angles at the joints of the finger. Further, a system
for measuring the angle has to be lightweight and compact enough
not to hinder natural motions of a hand.
[0042] As described above, there have been many tries for
accurately measuring the joints of the thumb and fingers. That is,
in the similarity approach using the optical linear encoder (OLE),
the encoder attached to the thumb and fingers and the thick and
wide wire cable for the optical encoder may interfere with a
natural motion of the thumb and fingers. In the 3D magnetic
position sensor 3 for measuring the angles at the joints of the
thumb and fingers, required peripheral devices may obstruct the
unconstrained hand motion. In the method of using the optical fiber
sensor, the optical sensor has to be carefully bent to measure the
angles at the joints, and by required peripheral devices such as a
laser diode and an optical power system extremely limits the
mobility of the optical sensor. In the method of using the flexible
resistor, it is economically inefficient and difficult to combine
with another system such as a hand exoskeleton system.
[0043] According to the present invention, a linear potentiometer
with a flexible wire and a linear spring is used for measuring
flexion/extension motions of a thumb and fingers. FIG. 3 shows
basic concept of the present invention. For better understanding,
an example of only one joint is shown in FIG. 3.
[0044] As shown in FIG. 3(a), the flexible wire (e.g. a fishing
line, etc.) is attached to a glove at a specific position (e.g.
`A`) in a thumb and fingers by tying or the like method. Since the
joint motions of the thumb and fingers joint motion are regarded as
rotary motions with respect to specific joints (e.g. `B` inside the
thumb or finger), the motion with respect to one joint can be
expressed as shown in FIG. 3(b). As the thumb or finger is crooked,
wrinkles at the joint of the thumb or finger are stretched out and
thus the attached line moves. The moved distance .DELTA.L is
calculated as follows.
.DELTA.L.sub.1=r.sub.1.theta..sub.1 [Equation 3]
[0045] where, r.sub.1 is a diameter of the joint in the thumb or
finger, and .theta..sub.1 is an angle at the joint.
[0046] The diameter of the joint in the thumb or finger may be
directly measured. The length change .DELTA.L.sub.1 is equal to
.DELTA.P and measured by the linear potentiometer length installed
as shown in FIG. 3(c). Thus, the angle at the joint is calculated
as follows.
.theta. 1 = .DELTA. P r 1 [ Equation 4 ] ##EQU00001##
[0047] When the thumb of finger is spread out to the initial
position, the thumb or finger wire is also returned to the initial
position by the spring installed in the potentiometer. If the
spring is not given, the flexible wire is loosed as shown in FIG.
3(d) and therefore the flexion of the thumb or finger can be
measured only once by the system. In other words, the spring serves
to keep constant tension of the flexible wire in accordance with
motions of the thumb or finger.
[0048] Prior to description of multi-joint joint cases, dependency
of between the joints of the finger has to be discussed. The DIP
joint motion is not independently movable, and dependent on the PIP
joint. A relationship between the DIP and PIP joints is
approximated as follows.
.theta. DIP = 2 3 .theta. PIP [ Equation 5 ] ##EQU00002##
[0049] where, .theta..sub.DIP and .theta..sub.PIP are angles at the
DIP and PIP joints, respectively.
[0050] However, a more accurate relationship is required to measure
angles at two joints by measurement at only one PIP joint. By the
accurate relationship between the DIP joint and the PIP joint,
measurements are carried out only twice with regard to one finger
having three degrees of freedom. The accurate relationship between
the DIP joint and the PIP joint is experimentally obtained, and
this will be described later.
[0051] Taking the dependency between the DIP joint and the PIP
joint, the present invention is designed as shown in FIG. 4. Like a
case of one joint, the angles at the respective joints are measured
by the linear potentiometer. Based on such a relationship, the
angle at the DIP joint can be obtained by the angle at the PIP
joint. Accordingly, only two potentiometers are used in measuring
the angles at the PIP and MCP joints, respectively.
[0052] If the finger is crooked from FIG. 4(a) to FIG. 4(b), the
moved distances .DELTA.L.sub.1 and .DELTA.L.sub.2 of the tied
positions are measured by two installed linear potentiometers as
follows.
.DELTA.P.sub.1=.DELTA.L.sub.1 [Equation 6]
.DELTA.P.sub.2=.DELTA.L.sub.1+.DELTA.L.sub.2 [Equation 7]
[0053] The angles at the joints are calculated as follows.
.theta. 1 = .DELTA. L 1 r 1 [ Equation 8 ] .theta. 2 = .DELTA. L 2
r 2 [ Equation 9 ] ##EQU00003##
[0054] Therefore, the angles at the joints are obtained by the
potentiometers as follows.
.theta. 1 = .DELTA. P 1 r 1 [ Equation 10 ] .theta. 2 = .DELTA. P 2
- .DELTA. P 1 r 2 [ Equation 11 ] ##EQU00004##
[0055] According to the present invention, only the changed
distances of the tied positions, which can be measured by the
flexible wire and the linear potentiometer, are required. One of
the advantages in the present invention is that the flexible wire
is bendable and thus there are no needs of aligning the wire with
the finger. Therefore, a sensing module 30, which includes the
potentiometer with the spring, is placed on a back of a hand, and a
flexible wire 20 is tied on a glove 10 and connected to the sensing
module 30 as shown in FIG. 5. For measurements at the PIP and MCP
joints, two flexible wires 20 are used for each of the thumb and
fingers, and respectively connected to the middle phalanx and
proximal phalanx. In addition, a thin cylindrical guide 40 is
mounted to the glove so that the wire can be properly bent.
[0056] Test
[0057] To test the performance of the system according to the
present invention, measured values of the present invention were
compared with the measured values of a small wireless inertial
measurement unit (IMU) sensor attached to the thumb and fingers.
The IMU sensor, which is capable of an angle at orthogonal 3-axial
joint, was used in measuring only the flexion/extension motion, and
then compared with the measurements of the potentiometer.
[0058] Before applying the system according to the present
invention to a human's hand, the concept of the present invention
was tested using a wooden hand. By the test using the wooden hand,
uncertainties of a glove or human hand (e.g. extension of a glove,
dependent rotation at each joint, etc.) were decreased.
[0059] The IMU sensor and the flexible wire were attached to the
wooden hand as shown at the left side in FIG. 6. The IMU sensor was
directly bonded to the wooden finger, and the flexible wire was
used to connect the wooden finger (between the DIP and PIP joints)
and the linear potentiometer having the restoring linear spring.
The potentiometer was placed on the back of the wooden hand. In the
test, the index finger was crooked at only the PIP joint but not
moved at the MCP joint. The signal measured by the potentiometer
was converted by the Equation 9 into the angle at the PIP joint.
The test results showed that two measured values were matched with
each other having an average error of 0.65 degrees.
[0060] As mentioned above, the dependency between the DIP and PIP
joints will be discussed below, and relation between them will be
derived. The motions of the thumb and fingers are generated by
combination of flexor digitorum profundus (FDP) and flexor
digitorum superficialis (FDS) muscles. Since the FDP simultaneously
generates motions at both the PIP and DIP joints, the motions at
these joints are coupled. The relation between these motions is
known as a linear relation, but a more accurate relation is
experimentally obtained as follows.
[0061] The angles at the DIP and PIP joints were measured many
times by the IMU sensor with respect to different participants.
FIG. 7 shows representative results. In the experiments, the
participants were requested to freely bend and extend their own
thumb and fingers without any constraint. The relation was derived
by a curve-fitting method. Average data from the experiments were
fitted by first-order and second-order as follows.
.theta..sub.DIP=0.989.theta..sub.PIP-0.230 [Equation 12]
.theta..sub.DIP=0.006.theta..sub.PIP.sup.2+0.674.theta..sub.PIP+0.104
[Equation 13]
[0062] where, .theta..sub.DIP and .theta..sub.PIP are angles at the
DIP and PIP joints, respectively.
[0063] Root mean square errors (RMSE) of first-order and
second-order cases were 3.104 degrees and 2.251 degrees,
respectively. The curved-fitting results showed that the angles at
the DIP and PIP joints are not linearly coupled, and the
second-order fitting is better than the first-order fitting.
However, this is significantly different from the well-known
first-order approximation based on the Equation 5.
[0064] A simulator for measuring angles at joints of a finger is
shown at the right side in FIG. 6. Three IMU sensors were attached
to an index finger and measured the angles at the DIP, PIP and MCP
joints. Two wires were respectively tied on the proximal phalanx
and middle phalanx of the glove and connected to two
potentiometers. In the experiment, a palm was kept flat and the
index finger was bent forward and backward many times as a typical
flexion/extension motion.
[0065] The values measured in the potentiometers were converted by
the Equations 10 and 11 into angles. All the values obtained by the
experiments generally showed that two measuring methods
considerably coincided with each other. However, the two measuring
methods were a little different in measuring the angle at the DIP
joint. This difference may be caused by errors accumulated in
measuring the angle at the PIP joint and modeling the relation
between the DIP and PIP joints.
[0066] Realization of the Invention
[0067] According to the present invention, ten potentiometers are
needed for measuring flexion/extension motions of a thumb and four
fingers. To make a compact and lightweight sensing module that does
not hinder a natural motion of a hand, a small linear potentiometer
having a stroke of 20 mm were used (see FIG. 8). As shown in FIG.
8(a), two potentiometers were arranged vertically to reduce the
size of the sensing module. The flexible wire was tied on each
level of the potentiometer, and connected to the glove through a
small hole in a frame. As shown in FIG. 8(a), the linear spring
designed based on a manual was installed to return the
potentiometer to the initial position when the thumb and fingers
are extended.
[0068] FIG. 8(b) shows the backside of the sensing module. The
potentiometer and the spring were installed through the backside of
the sensing module. The frame of the sensing module may be made of
various materials/by various methods. In this embodiment, the frame
of the sensing module was made of nylon and by rapid prototyping
technology. The frame has a size of 45.times.61.times.17.4 mm and a
weight of 39 g, which is compact enough not to hinder a hand
motion. The sensing module is attached to the glove, and a user
wears the glove as shown in FIG. 9.
[0069] The measured angles at the joints were shown in FIG. 10. In
this program, a stiff link body was modeled on a human's hand that
has fourteen degrees of freedom--a thumb having two degrees of
freedom and four fingers each having three degrees of freedom. This
program provides an intuitive interface about a wearable sensing
glove.
[0070] Although a few exemplary embodiments of the present
invention have been shown and described, it will be appreciated by
those skilled in the art that changes may be made in these
embodiments without departing from the principles and spirit of the
invention, the scope of which is defined in the appended claims and
their equivalents.
* * * * *