JP2002065641A - System for measuring finger movement - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a system for measuring an available movement of fingers in high accuracy and high sampling grade. SOLUTION: This system of measuring the movements of fingers 1 is equipped with plural light sources 11 attached to the fingers, a high-speed camera 12 for photographing the light sources 11 and a device for processing signals 13 for calculating a three-dimensional position of a finger by processing the signals outputted from the high-speed camera 12. The light source 11 is provided with a fixing member 111 that sandwiches the finger for fixing it, a pin member 112 extending toward the top side of finger and an LED 113 covered with a spherical glass cover, and plural light sources 11 attached to each one of fingers are sequentially lighted by pair as a group. The high-speed camera 12 photographs the light sources sequentially lit by a group one after another, and the device for processing signals 13 calculates an image data of each finger from the signals outputted from the high-speed camera 12, thereby determining a three-dimensional position of each finger.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a finger movement measuring system, and more particularly to a finger movement measuring system for measuring finger movement with high accuracy and a high sampling rate, while taking advantage of a commercially available optical motion capture device. The present invention relates to a finger movement measurement system that can be realized by improving the above.

[0002]

2. Description of the Related Art Hitherto, as a method for observing the movement of a human finger, the following methods have been proposed, some of which have been commercialized.

That is, as a first technique, a technique has been proposed in which the movement of a human finger is visually observed, a continuous photograph or a video camera is used to extract a basic movement pattern (for example, (1) Okada Tokutsuji: Analysis of finger movement and manual work, Biomechanism 3, University of Tokyo Press, Tokyo, (1975) 133 pages,
(2) Toru Omata: Manipulation of Primitive Object Rotating with Multi-Fingered Hand, Journal of the Robotics Society of Japan, Vol.14, No.6 (1996) 853
page).

As a second technique, a glove is worn, and a joint angle of a finger is detected from a change in the amount of light of an optical fiber laid on the glove, a signal from a strain gauge, or the like (for example, (1) Hiroo Iwata : Application to virtual reality,
Measurement and Control, Vol. 36, No. 9, (1997) p. 639, (2) http: //
www.virtex.com) has been proposed.

Further, as a third technique, a short pin whose tip emits light is attached to the back side of the finger, and the light spot (marker)
Method of tracking coordinates with two CCD cameras to obtain coordinates (Harumasa Isa, Masaharu Takano, Ken Sasaki: Development of a measurement system for manipulating human fingers, Journal of the Japan Society of Precision Engineering, Vol.64, No.8 (1998)
1127) has been proposed. Such a third technique is characterized by using a pin to place a marker away from the finger in order to prevent the marker from being hidden (occlusion) due to overlapping of fingers.

On the other hand, instead of a narrow measurement range like a finger,
A so-called motion capture system is commercially available as a device for observing and analyzing the motion of the entire human body, and has begun to be generally introduced into hospitals, rehabilitation facilities, sports research institutes, broadcasting / video studios, and the like. As a measuring method of such a device, there are a fourth method and a fifth method described below.

That is, as a fourth technique, a technique is known in which a large number of reflection markers are attached to a human body, and the movement of the markers is photographed by a high-speed CCD camera from multiple directions (for example, (1) Mochimaru Masaaki: Trends in body movement measurement technology, measurement and control, Vol. 36, No. 9 (1997) p. 609, (2) Kazuo Fukui: Motion Capture, Journal of the Institute of Image Information and Television Engineers, Vol.5
1, No. 8 (1997) p. 1120, (3) Hiroaki Ogawa: Latest Trend of Motion Capture, NIKKEI COMPUTER GRAPHICS, 3 (1999) 60
Page and (4) A.Macleod, JRW Morris and M.Lyster: High
Accurate Video Coordinate Generation for Automatic
3D Trajectory Calculation, SPIE Vol.1356 Image-Ba
sed Motion Measurement, (1990) p. 12). In the fourth method, pixel data obtained by capturing a marker is stored in a memory for each sampling time, and the association of the marker and the calculation of the three-dimensional position are performed offline after the measurement is completed. Therefore, real-time measurement is difficult. However, the characteristic is that the sampling rate of the measurement coincides with the sampling rate of the high-speed CCD camera.

[0008] As a fifth technique, a large number of LEDs are attached to a human body, and these LEDs are sequentially turned on one by one to form a PS.
A method of shooting with a D camera is known (Technical Pr
oduct Description OPTOTRAK, Northen Digital Inc, O
ntario, (1991) p.1). Such a fifth method eliminates the need for associating a light spot on an image with an actual marker.
The feature is that reliable light spot identification can be performed.

[0009]

However, the above-mentioned first to fifth conventional techniques have the following problems, respectively. That is, the first method has a disadvantage that a finger hidden from the observation direction cannot be observed and only qualitative data can be obtained.

[0010] The second technique has a drawback that the glove must be worn, giving the subject a sense of restraint, hindering natural movement, and hindering the sense of force and touch. There is also a problem that the position and orientation of the object to be manipulated cannot be measured at the same time. In particular, it has been reported that 50% or more of the work performed by human hands requires a force sensation, and it is a serious disadvantage that the force and tactile sensations are disturbed.

In the third method, since a general-purpose CCD camera is used, the image sampling rate is 30 Hz.
In addition to the above, a method of sequentially processing and discarding the data of 256 gray scales stored in the frame memory on the image processing board and discarding the data, the following processing is performed during the image processing related to the light spot tracking. Has the drawback that the image cannot be captured. Therefore, the biggest problem is that the sampling rate of the three-dimensional position measurement of all the light spots is about 1 Hz, and that only slow steering operation can be observed. If the number of cameras is 2
Since it is a table and an optical fiber whose tip is cut into a conical shape is used as a light spot, there is also a problem that the photographable range (posture of a photographable hand) is limited by the limit of light quantity and directivity. In consideration of the above problems, in order to push the third method to a practical level of performance, a user using a system using three or more high-speed cameras and a high-speed image processing board is required. It is necessary to develop, and it is considered that the development time, cost, and the like for that need become large.

Further, the fourth technique has a possibility that the measurement of a finger can be performed at a high sampling rate.
When the photographing range is narrow as in the measurement of a finger, occlusion frequently occurs, and there is a problem that erroneous recognition such as replacement of a marker or jumping occurs. For this reason, there is no report that such a fourth technique was used for finger measurement.

Finally, the fifth method has an advantage that it is not necessary to associate a light spot on an image with an actual marker, but the relative positions of the three PSD cameras are fixed on a straight line. In addition, since the directivity of the LED used is limited to ± 60 ° with respect to the front, when measuring a finger whose posture changes in a complicated manner, the PSD camera often cannot detect the light spot of the LED. There is a problem that it occurs.

SUMMARY OF THE INVENTION The present invention has been made to solve the problems of the related art, and has as its object to provide a finger movement measuring system capable of measuring finger movement with high accuracy and a high sampling rate. .

[0015]

In order to solve the above-mentioned problems, the present invention provides a plurality of light sources attached to a finger, a high-speed camera for imaging the light sources, and an output signal from the high-speed camera. A signal processing device for processing to calculate a three-dimensional position of the finger, wherein the light source comprises: a fixing member for holding the finger to fix the light source; and a back side of the finger from the fixing member. And a LE attached to an end of the pin and covered with a spherical glass cover.
D, and a plurality of light sources attached to each finger are sequentially turned on as a set, and the high-speed camera sequentially captures images of the light sources sequentially turned on for each set, and performs the signal processing. The apparatus provides a finger movement measurement system, wherein image data of each finger is calculated from an output signal of the high-speed camera, and a three-dimensional position of each finger is calculated.

According to the invention, since the light source is fixed by holding the finger with the fixing member, there is no need to wear gloves as in the related art, and the natural movement of the finger is not hindered. In addition, there is an advantage that the force sense and the tactile sense are not hindered. Further, since the LED is attached to the end of the pin member extending from the fixing member toward the back side of the finger, occlusion due to overlapping of the fingers can be prevented. In addition, since the LED is covered with a spherical diffusion glass cover, it becomes a substantially omnidirectional light source, and even if the posture of the finger changes complicatedly, it becomes possible to take an image with a camera, and the measurable range is expanded. You. Further, since a plurality of light sources attached to each finger are set as one set and sequentially turned on for each set, and the light sources sequentially turned on for each set are sequentially imaged by a high-speed camera, all the light sources are turned on once. Occlusion can be prevented as compared with the case where the image is picked up at the same time, and measurement at a higher sampling rate can be performed as compared with the case where each light source is turned on one by one. In this specification, the phrase "high-speed camera" is used to mean a camera having a sampling frequency higher than 30 Hz.

Preferably, the apparatus further comprises a calibration jig for calculating the three-dimensional position, wherein the calibration jig is substantially T-shaped by a first member and a second member extending from a substantially center of the first member. And a reflection marker attached to both ends of the first member.

According to such an invention, the entire rod can be translated while the second member is gripped and rotated, and more accurate calibration can be performed.

Further, the present invention provides a light source characterized by being formed from an LED covered with a spherical diffusion glass cover so as to have a substantially non-directional property.

In the light source according to the present invention, the LED is covered with a spherical glass cover so as to be a substantially non-directional light source. Therefore, if such a light source is used for measuring the movement of a finger, it is possible to take an image with a camera even if the posture of the finger changes in a complicated manner, and there is an advantage that the measurable range is expanded.

According to the present invention, there is provided a leaf spring formed so as to pinch a finger by a restoring force so as not to hinder the sense of force and touch, a pin member extending from the leaf spring toward the back side of the finger, A light source attached to an end of the pin member.

According to the light source with the fixture according to the present invention, the light source is fixed by pinching the finger by the restoring force of the leaf spring. Therefore, if such a light source is used for measuring the movement of the finger, there is an advantage that the natural movement of the finger is not hindered and the force sense and the tactile sense are not hindered. Further, since the light source is attached to the end of the pin member, occlusion due to overlapping of fingers can be prevented.

Further, the present invention includes a plurality of light sources attached to a finger, and a high-speed camera for imaging the light sources. The high-speed camera includes a plurality of light sources attached to each finger as a set. An imaging system is provided, which sequentially captures images of light sources sequentially turned on for each set.

When the imaging system according to the present invention is used for measuring the movement of a finger, occlusion can be prevented as compared with the case where all light sources are imaged at once, and compared with the case where each light source is turned on one by one. Measurement at a high sampling rate becomes possible.

Further, the present invention provides a method for controlling each finger based on image data obtained by sequentially imaging a plurality of light sources attached to each finger as a set and sequentially lighting the light sources for each set. The present invention provides a signal processing device wherein, after dividing image data for each finger, image data corresponding to each finger is connected.

According to the signal processing device of the present invention, the image data of each finger is provided in a connected state. Therefore, such image data of each finger can be easily applied to a commercially available optical motion capture device, and it is possible to measure a change in the three-dimensional position of each finger.

[0027]

An embodiment of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a schematic configuration diagram of a finger motion measurement system according to an embodiment of the present invention. As shown in FIG. 1, the measurement system 1 according to the present embodiment includes four fingers (in the present embodiment, four fingers excluding the little finger).
(A total of 16 light sources, 4 for each finger) attached to the light source 11 and a sampling frequency 20 for imaging the light source 11
A high-speed CCD camera 12 of 0 Hz and a signal processing device 13 for processing an output signal from the high-speed CCD camera 12 to calculate a three-dimensional position of the finger are provided.

As shown in FIG. 2, the light source 11 is formed of a leaf spring.
A pin member 112 extending from the fixing member 111 toward the back of the finger, an LED marker 113 attached to an end of the pin member 112 and covered with a spherical diffusion glass cover. It has. As described above, in the light source 11 according to the present embodiment, in order to prevent occlusion due to overlapping of fingers, the LED marker is installed at a position (30 to 65 mm) away from the finger via the pin member 112, and furthermore, In order to prevent occlusion by the member 112, the diameter of the pin member 112 is φ1 mm.
And set as thin as possible. In addition, the wiring is flexible and thin, and attention is paid so that the influence on the subject is reduced. Since the fixing member 111 holds and fixes the finger with the restoring force of the leaf spring, although a certain degree of restraint feeling is inevitable,
Since the surface of the finger is not covered, there is an advantage that the sense of touch and force of the finger is not impaired.

FIG. 3 shows the appearance of the LED marker 113. The LED marker 113 uses an LED as a light spot, and its glass cover is processed into a spherical shape to make it substantially non-directional. In the above-mentioned processing, after making a rough shape by hand manually using a file, the front part is finished by rotating while pressing against a hemispherical mold (surface roughness Ra = 60 μm to 200 μm) containing abrasive grains. Since the surface portion has terminal pins, it is finished by hand using sandpaper under a stereoscopic microscope. Furthermore, a white paint is applied to the surface of the glass cover in order to enhance the light diffusivity.

FIG. 4 shows measurement conditions when the directivity of the LED marker 113 is evaluated. As shown in FIG.
The marker 113 is rotated every 5 °, and this is
Images were taken with the camera 12 at a constant binarization level, and the directivity was evaluated from the angle range in which images could be taken. Further, for comparison with the LED marker 113 according to the present embodiment, the directivity of the marker by the LED and the optical fiber before processing was calculated under the same conditions, and the relative evaluation was performed. Table 1 shows the evaluation results.

[Table 1] As shown in Table 1, LE of this embodiment subjected to spherical processing
The D marker 113 has a wider directivity than the other markers, and substantially complete nondirectionality is realized under the measurement conditions shown in FIG. By using such an omnidirectional LED marker 113, a high-speed CCD
The camera 12 can reliably image the marker 113, and the measurable range (measurable finger posture) is expanded.

High-speed CCD camera 12 according to this embodiment
The signal processing device 13 is configured by using a commercially available optical motion capture device and improving it. That is, in the present embodiment, a typical Oxford Metrics Vicon370 as an optical motion capture device.
System high-speed CCD camera, marker association function,
In order to measure the movement of the human finger, which is likely to cause jumping or hiding of markers, using the 3D position calculation function etc. as it is,
Its hardware and software are additionally improved.

Here, as in the fifth method described above, L
The Vicon 370 system (light by image processing) is used to turn on the ED markers 113 one by one and perform reliable light spot identification by eliminating the need to associate light spots on an image with actual markers. If applied directly to the point identification method), the sampling frequency of each LED marker 113 will be 12.5 Hz, which is the sampling frequency of the camera 200 Hz divided by the number 16 of LED markers, and the advantage of using the high-speed CCD camera 12 will be lost. become. For this reason, in this embodiment, four LEs attached to each finger are used.
The D marker 113 is set as one set, and is turned on sequentially for each set (each finger) to perform time sharing. As a result, only four LED markers 113 of each finger are imaged in one frame of the high-speed CCD camera 12, so that all markers (16) are imaged in one frame. Switching and jumping of the markers 113 caused by overlapping (hiding) between the 113 are significantly prevented. The sampling frequency of each marker 113 is 200H
50 obtained by dividing z by the number of fingers 4 to which the marker 113 is attached.
Although reduced to Hz, this is sufficient for observing daily human finger movements. When the LED markers 113 are sequentially turned on for each set, as shown in FIG. 1, synchronization with each high-speed CCD camera 12 output from the data station 131 of the Vicon 370 system constituting the signal processing device 13 is performed. A circuit 132 is provided which utilizes a signal and sequentially distributes the signal to the LED driving circuit of each finger.

As shown in FIG. 1, in the Vicon 370 system constituting the signal processing device 13, the pixel information data (TVD file) 133 of the marker is processed by the dedicated software 134, and the three-dimensional position coordinate data (C3D file) of the marker is processed. 135 has been created. In the present embodiment, the TV
After dividing the D-file for each frame (frame), software 136 is developed which connects every four frames and reconstructs four TVD files for each finger (see FIG. 5). I have. By processing the reconstructed four TVD files with the dedicated software 134 again, four C3D files 135 for each finger can be obtained. In this way, the marker association function and the three-dimensional position calculation function of the commercially available motion capture device (Vicon370 system) are effectively used as they are.

In the case of a commercially available motion capture device (Vicon370 system), before measurement, an attached calibration unit 2 in which a reflection marker 21 is arranged in advance as shown in FIG. 6 is installed near the center of the measurement space. Defines the world coordinate system. After photographing such a calibration unit 2, the marker rod 3 in which two reflective markers 31 as shown in FIG. 6 are fixed at a known constant distance (500 mm) is gripped and uniformly placed in the measurement space. It swings around and captures the movement of the reflection marker 31 at this time. By the above operation, the camera parameters (from the position of the image of the reflection marker imaged on the screen of the camera, the position of the reflection marker in the three-dimensional space are calculated so that the distance between the two reflection markers 31 is calculated to a known value. (Coefficients in the coordinate conversion formula for calculating the coordinates) are calibrated. These calibration tools 2 and 3 included with the Vicon370 system
Since the movement of the entire human body is to be measured, the diameters of the reflection markers 21 and 31 and the distance between the markers 31 of the rod 3 are both set to large values. For this reason, when targeting a small measurement space of about 500 mm 3, such as a finger measurement, the estimation error of the camera parameter may increase.

Therefore, in this embodiment, as shown in FIG. 7, a small reflective marker 41 having a diameter of 5 mm is used to enable accurate calibration even in a small measurement space such as the measurement of a finger.
51, and the calibration unit 4 and the marker rod 5 are configured using the 51. Here, the reflection markers 41 and 51 are provided on commercially available glass beads,
"Scotchlite high-brightness reflective sheet white" manufactured by M. Co., Ltd. is cut into small strips (both ends are thin and the central part swells) and cut and attached. Marker rod 5
A rod formed in a substantially T-shape by a first member 52 and a second member 53 extending from a substantially center of the first member 52;
Reflection markers 51 attached to both ends of first member 52
And Therefore, it is possible to translate the entire marker rod 5 while gripping and rotating the second member 53, thereby enabling more accurate calibration.

[0036]

The characteristics of the present invention will be further clarified by showing examples.

Example 1 The accuracy of measuring the static position and angle of the finger motion measuring system 1 according to the present invention described above was verified. FIG. 8 shows the camera arrangement conditions. First, two LED markers were set at a fixed distance interval using a caliper as a calibration reference, and the system 1 measured the positions of the two markers and calculated the distance. In addition, three LED markers are placed one at the center of a circle with a radius of 50 mm and two on the circumference,
After the center angle of the sector formed by these markers was set at a fixed angle using the protractor as a calibration reference, the system 1 measured the positions of the three markers to calculate the center angle. Here, the measurement was repeated 50 times while changing the location in a space of 250 × 250 × 150 mm for each set distance and set angle. Tables 2 and 3 show the measurement results of the distance and the angle, respectively.

[Table 2]

[Table 3] As shown in Tables 2 and 3, the measured values of the system 1 and the measured values of the measuring instruments (calipers, protractor) used as the calibration standards are as follows.
The agreement is within 0.2 mm and within 0.1 °, respectively, indicating that the system 1 has relatively high position and angle measurement accuracy. Thus, the effectiveness of the spherical LED marker and the small space calibration tool developed for finger measurement according to the present invention could be confirmed.

(Embodiment 2) As shown in FIG. 9, the lengths L ₂ and L _{3 of} the second link and the third link are known, and the change in the angle θ ₃ of the third joint is encoded by an encoder (resolution of 0.1). 025
A pseudo finger link model that can be detected by (°) was created. Note that, in order to calibrate the relative positional relationship between the marker and the link, the marker P
₃₃ were installed. In such a pseudo finger link model, if the third link is rotated while the second link is fixed, and the trajectories drawn by the markers P ₃₁ , P ₃₂ , and P ₃₃ are measured, the link length L ₃ can be calibrated. it can. Table 4 shows the results of estimating L ₃ having four lengths in this manner.

[Table 4] As shown in Table 4, it is found that the measurement system 1 according to the present invention has a high trajectory measurement accuracy, and as a result, a high calibration accuracy of 1 mm or less can be realized under the condition that all the markers move in the same plane. Was.

Further, the third link of the pseudo finger model shown in FIG. 9 is pulled with a thread and rotated, and the markers P ₃₁ , P
_32, the position of P ₂ measured by the present system 1, T, the position of J _3, J ₂ determined using the relative positional relationship between the marker and the link is known, the angle formed by the TJ ₃ and J ₃ J ₂ From the joint angle θ ₃
Was calculated. FIG. 10 shows the result of comparing the change in the joint angle θ _{3 with} the change in angle obtained by the encoder. As shown in FIG. 10, when the rotation speed is relatively high (about 48 rpm), the rotation speed is 0.1 ° and when the rotation speed is low (about 7.6).
rpm) with an accuracy of about 0.3 °, confirming that the measurement system 1 according to the present invention has high dynamic joint angle measurement accuracy. The angular resolution of the glove-type measuring device according to the second conventional technique described above is nominally 0.5 °, and it can be confirmed that an external measurement can provide a dynamic accuracy equal to or higher than that of the occlusion measurement. This is one of the important features of the measurement system 1 according to the present invention, as well as the prevention of the measurement.

(Embodiment 3) Measurement system 1 according to the present invention
Was used to measure the human chopstick movements. Manipulating chopsticks requires complex finger coordination and cannot be achieved without advanced control capabilities. Therefore, if such an operation can be quantitatively analyzed at a high sampling rate, there is a possibility that it will contribute to research on the mechanism and control of the robot hand in the future. In addition, since four fingers are used and two objects (chopsticks) move simultaneously, occlusion is likely to occur, and no example of quantitatively measuring the operation of chopsticks is found. Therefore, the measurement of the chopstick operation is considered to be a good test bench for verifying the measurement ability of the measurement system 1 according to the present invention. In the second embodiment described above, the measurement system for the multi-fingers of the system 1 according to the present invention, the possibility of coping with changes in the posture of the fingers, the ability to prevent occlusion, and the like could not be verified. Investigation is also one of the objects of the present embodiment.

The camera arrangement condition in the present embodiment is shown in FIG.
It was the same as that shown in. The chopsticks are 223mm long,
The one having a diameter of 4 mm was used. In addition, one on each end of each chopstick
Attach four LED markers in total,
Attitude (excluding rotation around the axis) can be measured at the same time. Using the chopsticks having such a configuration, the chopsticks were continuously opened and closed without moving the wrist, and the movement of each finger and the chopsticks at that time was measured by the measurement system 1. Also, assuming that each finger is a cylinder (diameter uses the measured value of the finger), software that displays CG of these movements on the basis of the measured finger tip position, joint position, and chopstick position / posture is a PC work. Created on the station. FIG. 11 shows a CG display screen and a general-purpose video camera (sampling frequency 30H).
An example of the result of comparing the raw image of z) with the time axis is shown. As shown in FIG. 11, although qualitative, the measurement system 1 reliably moves the multi-finger and the object without being hindered by occlusion and without being affected by a complicated posture change of the finger. It turned out that measurement was possible.

FIGS. 12A to 12D show the second and third joint angles θ ₂ , θ 2 of each finger obtained by the present measurement system 1.
₃ shows an example of a time transition (see FIG. 1). As shown in FIG. 12, (1) the four fingers perform a periodic cooperative movement, (2) the movement of the index finger θ ₂ , θ ₃ , the middle finger θ ₂ , and the movement of the thumb θ ₃ are different. That these joints play an important role in chopstick manipulation,
(3) Although the movement of θ ₂ of the ring finger was small, knowledge such as slight movement without standing still was obtained for this subject. These findings can be obtained by visual observation or the like, but it is a feature of the measurement system 1 that quantitative data of joint angles can be obtained on a common time axis for each finger. It can be said that there is a possibility that a universal knack in a complicated maneuvering operation can be obtained by collecting statistical data and performing statistical processing.

[0043]

As described above, according to the finger measuring operation system of the present invention, the light source is fixed by holding the finger with the fixing member, so that the glove is worn as in the prior art. There is an advantage that there is no necessity, the natural movement of the finger is not hindered, and the force sense and tactile sense are not hindered. Also, since the LED is attached to the end of the pin member extending from the fixing member toward the back of the finger,
It is possible to prevent occlusion due to overlapping of fingers. In addition, since the LED is covered with a spherical diffusion glass cover, it becomes a substantially omnidirectional light source, and even if the posture of the finger changes complicatedly, it becomes possible to take an image with a camera, and the measurable range is expanded. You. Further, since a plurality of light sources attached to each finger are set as one set and sequentially turned on for each set, and the light sources sequentially turned on for each set are sequentially imaged by a high-speed camera, all the light sources are turned on once. Occlusion can be prevented as compared with the case where the image is picked up at the same time, and measurement at a higher sampling rate can be performed as compared with the case where each light source is turned on one by one.

As described above, according to the measurement system of the present invention, since the movement of the finger can be measured with high accuracy and a high sampling rate, the following effects can be expected.

That is, first, it is expected that a guideline for designing a mechanism and a control system of a robot hand having the same level of dexterity and flexibility as humans can be derived. In the future, robots
It is expected to perform work performed by humans in environments that coexist with humans, such as in homes and hospitals, as well as in factories. For this reason, many researches on multi-fingered robot hands, which have versatility in various environments like human hands and can perform dexterous and flexible work, have been carried out from the viewpoint of mechanism and control. Among them, in the field of research on control, kinematics and
A method of theoretically conducting a dynamic analysis and then deriving a control law,
The method is broadly classified into a method of observing the motion of a human finger and extracting a control law therefrom. In the former case, it is necessary to verify the validity of the theoretical model in comparison with the movement of the human finger. On the other hand, in the latter case, it has been common practice to extract the basic movement pattern by observing the movement of the human hand with visual observation, a continuous photograph, a video camera, or the like. The problem is that observations cannot be made and only qualitative data can be obtained. Against this background,
Quantitative measurement of human finger motion is currently an important issue. The present invention solves such a problem, and is expected to be a powerful tool in research in the field of robot hands.

Second, in the field of medicine and rehabilitation, it is expected that the severity and healing status of finger movement disorders can be accurately and easily grasped. Medicine,
In the field of rehabilitation, it is common practice to provide a relatively large marker to a thigh, a knee, or the like, and to photograph it with a motion capture device to analyze human walking. However, there are no reports of quantitative movement analysis of fingers in the fields of medicine and rehabilitation. This is because when a finger is measured with a motion capture device, the measurement range is narrow and markers are easily concentrated, so that the markers are easily replaced or jumped, and it is difficult to obtain accurate data.
ADVANTAGE OF THE INVENTION According to this invention, the quantitative motion analysis of a human finger is attained, and it is expected that the level of clinical treatment and basic research in the fields of medicine and rehabilitation for finger movement disorders will be greatly increased.

Third, it can be expected that human sports skills and performance skills can be improved based on scientific training. As a recent sports training method, using a motion capture device to capture the human body motion into a computer, theoretically analyze the torque and floor reaction force generated at the joints, and how to improve the form to obtain better records Scientific considerations have been made to see if it is possible. However, despite the fact that there is no sporting event that does not use fingers at all, accurate measurement of finger movements is difficult, so the analysis targets are arms,
In fact, it is limited to legs and torso. The present invention
It is expected to break this situation and contribute to the establishment of a scientific sports training method based on comprehensive motion analysis including fingers. Also, in the field of art, if the present invention makes it possible to observe and analyze the movements of human fingers in playing musical instruments such as violins and pianos, the realization of training methods to improve scientific performance techniques will be realized in the future. Can be expected.

Finally, fourth, in the field of computer graphics (CG), it is expected that input of human motion data to a computer will be facilitated. In the production of CG images in computer games, the production of special images in SFX movies, etc., recently, actual motions of human beings are measured with a motion capture device, and the motion data is taken into a computer to perform various processings. It is becoming common sense to create realistic images that remind viewers of the sensation of a real human being there. However, since the measurement of the movement of the finger cannot be performed, the current state is that the part is drawn as before, relying on the imagination of the CG maker. ADVANTAGE OF THE INVENTION According to this invention, CG production of a real finger part becomes easy, As a result, improvement of the technical level of the amusement field, such as a game and a movie, can be expected in the future.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a finger motion measurement system according to an embodiment of the present invention.

FIG. 2 is a schematic configuration diagram showing a light source of the motion measurement system shown in FIG.

FIG. 3 is an LE of the motion measuring system shown in FIG. 1;
3 shows the appearance of a D marker.

FIG. 4 shows measurement conditions when the directivity of the LED marker shown in FIG. 3 is evaluated.

FIG. 5 is a conceptual diagram showing a concept of reconstructing a TVD file in the motion measurement system shown in FIG.

FIG. 6 shows a conventional calibration tool.

FIG. 7 shows a calibration tool of the motion measurement system shown in FIG.

FIG. 8 shows a camera arrangement condition in the embodiment.

FIG. 9 is a schematic configuration diagram of a pseudo finger link model used in the second embodiment.

FIG. 10 shows an example of an experimental result of Example 2.

FIG. 11 shows an example of an experimental result of Example 3.

FIG. 12 shows another example of the experimental results of Example 3.

[Explanation of symbols]

 Reference Signs List 1 finger movement measurement system 11 light source 12 high-speed CCD camera 13 signal processing device 111 fixing member 112 pin member 113 LED marker

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2F065 AA04 AA31 BB05 BB29 CC16 DD00 DD06 EE00 FF04 FF61 GG07 GG13 HH02 JJ03 JJ05 JJ26 LL19 LL49 NN02 QQ00 SS02 SS13 4C038 VA04 VB13 VC01 5B012 CA16CB

Claims (6)

[Claims] 1. A plurality of light sources attached to each finger, a high-speed camera that images the light sources, and a signal processing device that processes an output signal from the high-speed camera to calculate a three-dimensional position of the finger. A measurement system comprising: a light source, a fixing member that clamps the finger to fix the light source, a pin member extending from the fixing member toward the back of the finger, and an end of the pin member. LED, which is attached and covered with a spherical diffusion glass cover, and is sequentially turned on for each set as a plurality of light sources attached to each finger, and the high-speed camera is sequentially set for each set. The light source is sequentially imaged, the signal processing device calculates image data for each finger from an output signal of the high-speed camera, and calculates a three-dimensional position for each finger. Motion measurement system. 2. A calibration jig for calculating the three-dimensional position, wherein the calibration jig is substantially T-shaped by a first member and a second member extending from a substantially center of the first member. A rod formed on the
The finger movement measurement system according to claim 1, further comprising: reflection markers attached to both ends of the first member. 3. A light source comprising an LED covered with a spherical diffusion glass cover so as to have a substantially non-directional property. 4. A leaf spring formed so as to pinch a finger by a restoring force so as not to disturb the sense of force and touch, a pin member extending from the leaf spring toward the back side of the finger, And a light source attached to the end. 5. A light source comprising: a plurality of light sources attached to a finger; and a high-speed camera for imaging the light sources, wherein the high-speed camera includes a plurality of light sources attached to each finger as a set. An imaging system, which sequentially captures images of sequentially lit light sources. 6. Image data corresponding to each finger based on image data obtained by sequentially photographing light sources sequentially lit for each group with a plurality of light sources attached to each finger as a set. A signal processing device for connecting the image data corresponding to each finger after the division.