JP4071511B2 - Grip shape design system - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a grip-shaped design system. In particular, the present invention relates to a system suitable for designing a grip shape according to the usage situation of the elderly and the disabled.
[0002]
[Technical background]
The grips (grips) that humans hold with their hands are assigned to mass-produced products such as walking sticks and umbrellas, and cannot be created for each individual. Custom-made grips are not used because the craftsmen manually create them for each individual because they are expensive.
An elderly person or a person with an injury to the hand needs a grip that matches the person's athletic ability, but because it is expensive and few people create it manually, the necessary grip shape is required. The current situation is that it cannot be obtained.
[0003]
[Problems to be solved by the invention]
An object of the present invention is to provide a grip shape design system that can easily obtain a grip shape that matches the use situation of an individual.
[0004]
[Means for Solving the Problems]
In order to achieve the above object, the present invention is a grip-shaped design system, which is an operation input means for inputting coordinate values and bending angles of finger and palm joints, which are time-series data of an operation grasped by a user. A three-dimensional model for creating a three-dimensional model of the hand by adding data of finger thickness and palm thickness measured in advance to the set data of the broken line of the hand obtained from the data from the motion input means Characterized in that it comprises model creating means, spatial polygon surface creating means for obtaining a polygonal surface of the space inside the palm of the grasped hand from the three-dimensional model, and curved surface approximating means for approximating the spatial polygon surface by a curved surface. To do.
Furthermore, it is also possible to provide a mold creating means for obtaining a male surface of the mold with the obtained grip shape as a female surface.
A program for causing a computer system to construct each function of the grip-shaped design system and a recording medium storing the program are also the present invention.
[0005]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a diagram illustrating a configuration example of a grip shape design system 100 according to an embodiment of the present invention. As shown in FIG. 1, this system includes a globe 140 that can detect the position of a hand and the angle of a joint such as a finger, a magnetic field generator 130 for detecting the position of the globe, a magnetic field generator 130, and a globe 140. The controller 120 is configured to control and receive position information from the globe 140, and an interface 150 to receive angle information from the globe 140.
The table of FIG. 2 shows the specifications of Cyber Glove (T) sold by Solid Ray Laboratory Co., Ltd., which is used as a glove 140 for detecting hand movements in this system. Anything can be used as long as it can detect the movement of the hand as well as the cyber glove.
[0006]
As shown in FIG. 2, the cyber glove can measure a three-dimensional position as a position measurement, with a radius of 76 cm from the magnetic field generator 130 with an accuracy of 0.08 cm for each of X, Y, and Z. Can be detected. Up to four magnetic position sensors can be attached to the globe.
In Cyber Glove, the angle is detected by converting the distortion rate into voltage using an optical fiber, and 18 or more angles can be detected linearly in real time. As an example of the 18 detection angles,
1. 1. Bending angle at the base of thumb 2. Bending angle to the palm of thumb 3. Bending angle of thumb joint 4. Open and close thumb and index finger 5. Bending angle of index finger to palm 6. Bending angle of index finger joint Bending angle to the palm of middle finger 8. Bending angle of middle finger joint Open and close index and middle fingers10. 10. Bending angle of ring finger to palm Bending angle of ring finger joint 12. Open / close middle finger and ring finger Bending angle of little finger to palm 14. Bending angle of little finger joint 15. Opening and closing ring finger and little finger 16. 16. Opening and closing the little finger and thumb facing each other. Wrist movement up and down 18. It is possible to detect the movement of the wrist from side to side. The detected angle data can be sent to the computer system 110 via the interface 150, for example, serially.
[0007]
How the grip shape can be obtained in the system configuration shown in FIGS. 1 and 2 will be described with reference to the flowchart of FIG.
In order to obtain a grip shape with this system, first, for example, a rubber bag containing a soft jelly-like substance is prepared. Any other rubber bag can be used as long as it changes shape according to the gripping action of the user (subject). Also, the length and thickness of the user's (subject's) hand and palm are measured and input to the computer system in advance.
This rubber bag is placed on a desk and the user (subject) reaches out and holds it. Thereafter, the user performs a series of operations of holding the gripped rubber bag with force and returning it to the desk.
In this series of operations, the user wears the data glove, so when the finger or palm is moved, the information about the coordinate value of the joint of the finger palm and the bending angle of the joint at the moment is converted into serial data. Sequentially written to a file in the computer system (S202).
[0008]
This data includes, for example, the coordinate values x, y, z of the first joint of the index finger at a certain instant t and the bending space angles a, b, c are the coordinates (0, 0) of the wrist center where the position sensor is installed. , 0) and relative displacement from the angle (0, 0, 0). The same applies to the other 17 joints.
For this reason, at time t,
About joint 1: Marks (x ₁ , y ₁ , z ₁ ), (a ₁ , b ₁ , c ₁ )
. . . . . .
For joint n: coordinates (x _n , y _n , z _n ), angle (a _n , b _n , c _n )
. . . . . .
Regarding the joint 18: mark (x ₁₈ , y ₁₈ , z ₁₈ ), angle (a ₁₈ , b ₁₈ , c ₁₈ )
It is. It is recorded in the same way at different times t.
The relative position and angular displacement of each of the 18 joints at each time is written in a file as ASCII data. The user can read the contents of the file visually.
The obtained time-series data records time-series changes in the coordinates and angles of the contact portions of the broken line, assuming that the finger of the hand is a set of broken lines (see S202).
[0009]
Next, finger thickness and palm thickness data, which has been input to the computer of the individual user, is added to a set of broken lines representing the hand (S204). Thereby, the state of the user's finger or palm can be accurately reproduced. FIG. 4 shows only the finger at this stage as a three-dimensional image. 4A is a front view, FIG. 4B is a side view, and FIG. 4C is a plan view. In this way, hand movement can be reproduced as a three-dimensional model.
[0010]
From the obtained three-dimensional model of the hand, the space inside the palm that has been completely grasped can be defined as a set of polygonal surfaces having a polygonal line as an end point (S206). FIG. 5 shows this stage as a three-dimensional image. FIG. 5 shows that a set of polygon faces is generated inside the finger. 5A is a front view, FIG. 5B is a side view, and FIG. 5C is a plan view. FIG. 6 shows only the defined polygon surface. 6A is a front view, FIG. 6B is a side view, and FIG. 6C is a plan view.
The set of polygon surfaces defined in this way is approximated as a curved surface group (S208). As the grip surface, those having corners as shown in FIG. 6 are inappropriate, and a smooth curved surface suitable as a grip (grip) surface is obtained.
[0011]
In this way, it is possible to obtain a “grip” shape that conforms to the curved surface formed by the inside of the palm of the user in a state in which it is completely grasped. The shape of the “grip” can be formed from a material such as wood or plastic by NC processing, for example, using existing CAD / CAM technology. FIG. 7 shows an example of two grips (grips) created in this way.
Thus, a grip having a shape optimal for the user can be obtained.
[0012]
If a mold is necessary for producing the grip, a convex male surface having the grip curved surface as a female surface can be created to obtain a grip mold (S210). Using this mold, a grip can be made of plastic or the like.
By attaching the grip created in this way to a cane or the like, a cane or the like that is easy for the user to grip is created.
[0013]
<Usefulness of obtained time-series data>
For example, a case where a user whose right index finger is incapacitated due to cerebral blood flow, etc., is asked to wear a data glove and perform an operation of gripping a cane or gripping a cup with the right hand. In this user, since the index finger is inconvenient, another finger (for example, the middle finger) that moves freely is moved to touch the “grip” (that is, the rubber bag). Then, the other finger sequentially touches the “grip”, and the handicapped index finger finally touches the “grip” or remains untouched.
In this system, time series data is recorded, so in such users,
Item 1: State where finger palm is completely separated from “gripping” Item 2: Transition of state where free finger sequentially touches “gripping” Item 3: State where “gripping” is completely grasped Such time-series finger / palm motion data is obtained.
By using this motion data, it is possible to know which finger is incapacitated and the level of inconvenience. Therefore, in the above item 2, the fingertip that first touches the “gripper” surely secures the “gripper”. As described above, for example, by attaching a small non-slip rubber plate or the like to the portion of the “grip”, it is possible to help ensure the “grip”. With the existing method, only data relating to item 3 was obtained.
[0014]
【The invention's effect】
By using the configuration of the present invention as described above, it is possible to obtain an optimum grip shape corresponding to the user's individual exercise ability and obtain a grip having the shape by using CAD / CAM. .
[Brief description of the drawings]
FIG. 1 is a diagram showing a system configuration of an embodiment of the present invention.
FIG. 2 is a table showing the specifications of the cyber glove used in the embodiment.
FIG. 3 is a flowchart showing a processing flow for obtaining a grip shape;
FIG. 4 is a diagram illustrating a three-dimensional image of detected hand movements.
FIG. 5 is a diagram illustrating a state in which the inside of a palm is defined as a set of polygonal surfaces based on hand movements.
FIG. 6 is a diagram showing a set of defined polygon surfaces.
FIG. 7 is a diagram showing a grip created by CAD / CAM based on the shape of the obtained grip.
[Explanation of symbols]
100 grip shape design system 110 computer system 120 controller 130 magnetic field generator 140 globe 150 interface

Claims (4)

A grip-shaped design system,
Action input means for inputting coordinate values and bending angles of finger and palm joints, which are time-series data of actions gripped by the user;
A three-dimensional model that creates data of a three-dimensional model of a hand by adding pre-measured finger thickness and palm thickness data to the set data of the broken line of the hand obtained from the data from the motion input means Creating means;
A spatial polygon surface creation means for obtaining a polygonal surface of the space inside the palm in the gripped state from the three-dimensional model;
A grip shape design system comprising: curved surface approximation means for approximating the spatial polygon surface by a curved surface. In the grip shape design system according to claim 1,
Furthermore, the grip shape design system characterized by comprising a mold creating means for obtaining a male surface of a mold, wherein the obtained grip shape is a female surface. A recording medium storing a program for causing a computer system to construct each function of the grip-shaped design system according to claim 1. A program for causing a computer system to construct each function of the grip-shaped design system according to claim 1.

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