CN105945945A - Finger module dividing method based on analysis of moving functions of human hand - Google Patents

Abstract

The invention relates to a finger module division method based on the analysis of the human hand motion function, which relates to a finger module division method, in particular to a finger module division method based on the human hand motion function analysis. The invention aims to solve the problems of complicated degrees of freedom of human hands and difficult simulation. The specific steps of the present invention are: Step 1, establishing the grasping posture library of the human hand; Step 2, analyzing the motion characteristics of the joint itself; Step 3, analyzing the motion characteristics between the joints; Step 4, analyzing the correlation proportional coefficient; Step 5, analyzing the anatomy of the human hand Learning and the frequency of use of each finger in different grasps. The invention belongs to the field of robots.

Description

Finger module division method based on analysis of human hand motion function

technical field

The invention relates to a finger module division method, in particular to a finger module division method based on human hand motion function analysis, and belongs to the field of robots.

Background technique

As the most complex part of the human body, the human hand shows a high degree of dexterity in daily life. This is mainly reflected in the fact that in daily life, human hands can change different postures to complete the grasping of various types of objects. In order to simulate the grasping ability of human hands, various humanoid dexterous hands have emerged in the field of robotics. Since the human hand is a model for imitating the human hand design, in order to simulate the dexterous grasping and operating capabilities of the human hand, the research focus of the dexterous hand design has always been the development of a highly integrated mechatronics system based on the maximum degree of freedom of simulating the human hand. Typical Such as HIT-DLR II, etc., but as far as the current technological level is concerned, it is impossible to completely simulate the freedom of human hands under the strict size and weight restrictions of human hands. From the perspective of control, the human hand is composed of five fingers. According to the distribution of the degrees of freedom of the human hand, each of the four fingers contains at least four degrees of freedom, and the thumb contains at least five degrees of freedom. However, in terms of fingertip position control In other words, each finger is a redundant serial robot, not to mention that the whole hand is composed of a thumb and four fingers, so such a redundant and complex control system will bring difficulties to control. Therefore, the simplification of the degrees of freedom is particularly important, no matter from the structural design of the human-like hand or the control.

Recent studies in neuroscience have shown that although the human hand has so many degrees of freedom to complete the complex grasping tasks in daily life, the corresponding grasping poses in so many grasping tasks can be linearly combined through a small number of characteristic poses , and the recurrence error can be kept within an acceptable range. As a result, the actual degrees of freedom of the human hand in performing the grasping task can be reduced to a few.

From an anatomical point of view, it is very difficult or even impossible to drive a certain joint completely independently because the driving tendons of the human hand joints are intertwined and interact with each other. Therefore, due to the special anatomical relationship between the movements of the various joints of the human hand, there is a certain correlation between the movements of the joints. Combining studies in neuroscience and anatomy provides a theoretical basis for the simplification of degrees of freedom.

Contents of the invention

In order to solve the problems of complicated degrees of freedom and difficult simulation of human hands, the present invention further proposes a finger module division method based on the analysis of human hand motion functions.

The technical scheme that the present invention takes for solving the above problems is: the concrete steps of the method of the present invention are as follows:

Step 1. Establish a human grasping pose library;

Step 2. Analyze the motion characteristics of the joint itself;

Step 3. Analyze the motion characteristics between joints;

Step 4, analyzing the correlation proportional coefficient;

Step 5. Analyze the anatomy of the human hand and the frequency of use of each finger in different grasps.

The beneficial effects of the present invention are: the present invention realizes the simplification of the degree of freedom of the human hand on the basis of reproducing the movement function of the human hand as much as possible, and can also be used for the simplification of grasping control of various imitation human hands. At the same time, this method of simplification of degrees of freedom can also be used in the structure design of human-like hand in the theory of posture coordination, which can reduce the coefficient ratio of metacarpophalangeal joints and interphalangeal joints in feature poses, and also include Interphalangeal joints, so as to reproduce the grasping function of human hands more comprehensively, to realize the independent drive of metacarpophalangeal joints and interphalangeal joints, and reproduce the dexterity of human grasping.

Description of drawings

Fig. 1 is a principle diagram of the present invention, and Fig. 2 is a schematic diagram of a specific implementation process of the present invention.

detailed description

Specific embodiment one: illustrate this embodiment in conjunction with Fig. 1 and Fig. 2, the specific steps of the finger module division method based on human hand motion function analysis described in this embodiment are as follows:

Step 1. Establish a human grasping pose library;

Step 2. Analyze the motion characteristics of the joint itself;

Step 3. Analyze the motion characteristics between joints;

Step 4, analyzing the correlation proportional coefficient;

Step 5. Analyze the anatomy of the human hand and the frequency of use of each finger in different grasps.

In this embodiment, the human hand joints are divided into a thumb module and a four-finger module, and the four-finger module is divided into a metacarpophalangeal abduction-adduction joint module, a metacarpophalangeal extension-flexion joint module, an interphalangeal extension-flexion joint module, and a far finger extension-flexion joint module. Flexion joint module. Anatomically, there is a strong coupling relationship between the extension-flexion of the distal phalanx of the four fingers and the extension-flexion of the interphalangeal joint, which has become a consensus on the simplified design of the current imitation human hand. The default is to couple the drive with the interphalangeal joint, so the joint motion characteristics of the four-finger distal phalanx are not analyzed. At the same time, anatomically, the thumb has more independent and richer functional muscles than the rest of the fingers, so the movement of the thumb is more independent than that of the other four fingers. Generally, the thumb is designed and driven as an independent module in the design and control of the human-like structure It has also become a consensus in the field of robots, so the present invention also uses the thumb as a module separate from the remaining four fingers.

In this embodiment, the four fingers are divided into five modules, namely module A, module B, module C, module D, and module E; where module A includes the metacarpophalangeal joint of the index finger, and module B includes the interphalangeal joint of the index finger and Distal phalangeal joints, interphalangeal joints and distal phalangeal joints of the middle finger, module C includes the base joints of the middle finger and metacarpophalangeal joints of the ring finger, module D includes the metacarpophalangeal joints and far phalanx joints of the ring finger, interphalangeal joints and far phalanx joints of the little finger , module E includes the metacarpophalangeal joint of the little finger, the active joint of module B is the interphalangeal joint of the index finger, and the other joints are coupled with the active joints according to a certain transmission ratio, the active joint of module C is the metacarpophalangeal joint of the middle finger, and the other joints are coupled according to a certain transmission ratio. The transmission ratio is coupled with the active joint, the active joint of module D is the interphalangeal joint of the little finger, and the other joints are coupled with the active joint according to a certain transmission ratio.

Specific embodiment two: this embodiment is described in conjunction with Fig. 1 and Fig. 2, the method for dividing finger modules based on the analysis of human hand motion function in this embodiment is characterized in that: in step 1, a human hand grasping gesture library is established to reflect the human hand's grasping posture. The specific steps are as follows:

Step 1 (1), select 10 subjects, and each subject grasps 6 objects of different shapes and sizes. During the grasping process, the position of the wrist of the human hand is fixed and cannot be translated, but the wrist can be adjusted in different postures to grasp objects. crawling;

Step 1 (2), each subject adjusts the wrist to different postures to complete the grasping of 6 objects located in 27 relative positions relative to the front, middle, back, left, middle and right, and upper, middle, and lower of the human hand. Each object is grasped twice ;

Step 1 (3), establishing a human hand grasping gesture library, which includes 27×2×6×10=3240 grasping gestures.

Other components and connections are the same as those in the first embodiment.

Specific embodiment three: This embodiment is described in conjunction with Fig. 1 and Fig. 2. In the second step of the finger module division method based on the analysis of human motion function in this embodiment, the analysis of the kinematic characteristics of the joint itself is used to omit the consistency of joint angles in different grasps. degrees of freedom, on this basis, only the four-finger metacarpophalangeal joint abduction-adduction, metacarpophalangeal joint extension-flexion and interphalangeal joint extension-flexion joint kinematics characteristics analysis, in the constructed human grasping posture library Basically, compared with other types of joint degrees of freedom, it can be concluded that in different grasps, the abduction-adduction joint angles of the four fingers of the human hand do not change much, and the consistency is strong. Therefore, the abduction-adduction joint angle of the four fingers of the human hand The degree of freedom of the joints is omitted, and the extension-flexion joints of the four fingers of the human hand and the extension-flexion joints of the interphalangeal joints are reserved. Metacarpophalangeal joint abduction-adduction, therefore, the number of coupling modules corresponding to metacarpophalangeal extension-flexion joint should be less than that of interphalangeal extension-flexion joint. Other components and connections are the same as those in the first embodiment.

Specific embodiment four: this embodiment is described in conjunction with Fig. 1 and Fig. 2, the finger module division method based on the analysis of human motion function described in this embodiment is characterized in that: in step 3, the analysis of the kinematic characteristics between joints is used to use the remaining joints The degrees of freedom were divided into modules. Under the correlation analysis of the reserved joint degrees of freedom, one pair and two pairs of joints with high correlation were determined in the metacarpophalangeal extension-flexion joints and interphalangeal extension-flexion joints. Other components and connections are the same as those in the first embodiment.

Specific embodiment five: this embodiment is described in conjunction with Fig. 1 and Fig. 2, the finger module division method based on the analysis of human hand movement function described in this embodiment, it is characterized in that: in the step 4, analyze relevant proportional coefficients and be used to determine the value of each module Active degrees of freedom, when the active degrees of freedom in each coupling module are the joints corresponding to the red dots, the coupling coefficients of the three coupling driving modules have a small difference, so the red dots in each coupling module are selected as the active joints of the coupling driving modules. degrees of freedom.

6. The finger module division method based on the analysis of human hand movement function according to claim 1, characterized in that: in step 5, analyze the anatomy of the human hand and the frequency of use of each finger in different grasps for the analysis basis of the reference correlation proportional coefficient The active degrees of freedom of the coupled modules are finally determined on .

According to the common sense of anatomy, the index finger and little finger of the human hand are independently driven by more independent functional muscles than the middle finger and ring finger. Therefore, according to the common sense of human anatomy, the active degrees of freedom of modules B and D in Figure 2(4) are consistent with the active degrees of freedom determined by the correlation proportional coefficient analysis, so the status quo is maintained. Judging from the frequency of use of each finger in different grasps, the index finger and middle finger of the four fingers are used more frequently than the middle finger and ring finger. Therefore, the active degrees of freedom of module C in Fig. 2(4) are consistent with the active degrees of freedom determined by the correlation proportional coefficient analysis, so the status quo is maintained. And because there is a strong coupling relationship between the extension-flexion of the distal phalanx of the four fingers and the extension-flexion of the interphalangeal joint in anatomy, the outer phalangeal joints of the four fingers are incorporated into the coupling module to obtain the final joint modularization result .

Other components and connections are the same as those in the first embodiment.

The present invention breaks the traditional method of dividing a single finger into a module. The whole process of hand joint division into modules is shown in FIG. 1 , and the detailed result of joint division into modules is shown in FIG. 2 . As shown in Figure 1, firstly, through a large number of human grasping experiments, a human grasping gesture library that fully reflects the grasping ability of human hands is constructed.

Due to the complexity of human hand joints, it is difficult to use for unified analysis, and from an anatomical point of view, the same type of joints are often driven by the same functional muscle. In terms of functional muscle drive alone, different types of joint drives are relatively independent. Therefore, the human hand joints are divided into a thumb module and a four-finger module, and the four-finger module is divided into a metacarpophalangeal joint module, an interphalangeal joint module, and a far finger joint module.

On the basis of the human hand grasping posture library, the kinematic characteristics of each finger joint are analyzed, and the division method of finger joint modules is obtained. In order to analyze the kinematic characteristics of human hand joints more comprehensively, the kinematic characteristics of the joints are divided into the kinematic characteristics of the joint itself and the kinematic characteristics between the joints. It can be quantified by descriptive statistics such as joint variance. If the joint angle varies greatly in different grasps, it indicates that the joint exhibits different joint angles in different grasps. The embodiment of ability, from the perspective of reproducing the grasping posture of the human hand, should retain the joint degrees of freedom with large joint angle changes in different grasps. In contrast, the joint freedom with small joint angle changes in different grasps should be ignored Spend. Therefore, the kinematic characteristics of the joint itself are taken as the basis for simplification of the degrees of freedom of the human hand joints.

The motion characteristics between joints reflect the correlation of the angle changes of each joint in different grasping motions, which can be quantified through correlation analysis and other situations. According to the correlation analysis results, the joint pair with high motion correlation is selected as the coupling drive module . Realize the module division of human hand joint degrees of freedom.

After analyzing the motion characteristics of the joint itself and the motion characteristics between the joints, the coupling drive module is obtained. Due to the single-input and multiple-output form of the coupling drive module, whether it is structural design or control, it is necessary to obtain the active control in the coupling drive module. degrees of freedom to realize the coupled movement of the coupled drive module. Therefore, select an appropriate active degree of freedom in the coupling module, and ensure that the coupling proportional coefficients in each coupling module are similar as much as possible according to the joint coupling drive correlation proportional coefficient after the active degree of freedom is selected, in order to make the coupling energy in each module The same set of coupling drive mechanism is used to simplify the mechanical design as much as possible. At the same time, the anatomical basis of the human hand and the actual frequency of use of each joint in different grasps can also be referred to to finally determine the active degrees of freedom in the coupling module.

The above description is only a preferred embodiment of the present invention, and does not limit the present invention in any form. Although the present invention has been disclosed as above with preferred embodiments, it is not intended to limit the present invention. Anyone familiar with this field Those skilled in the art, without departing from the scope of the technical solution of the present invention, may use the technical content disclosed above to make some changes or modify equivalent embodiments with equivalent changes, but as long as they do not depart from the technical solution of the present invention, according to the technical content of the present invention Within the spirit and principles of the present invention, any simple modifications, equivalent replacements and improvements made to the above embodiments still fall within the scope of protection of the technical solutions of the present invention.

Claims (6)

1. based on the finger module division method of human hand motion function analysis, it is characterized in that: the concrete steps of the finger module division method based on human hand motion function analysis are as follows: Step 1. Establish a human grasping pose library; Step 2. Analyze the motion characteristics of the joint itself; Step 3. Analyze the motion characteristics between joints; Step 4, analyzing the correlation proportional coefficient; Step 5. Analyze the anatomy of the human hand and the frequency of use of each finger in different grasps. 2. according to claim 1, based on the finger module division method of human hand motion function analysis, it is characterized in that: in the step 1, set up the hand grasping gesture storehouse to be used for reflecting the hand grasping ability, and its concrete steps are: Step 1 (1), select 10 subjects, and each subject grabs 6 objects of different shapes and sizes. During the grasping process, the wrist position of the human hand is fixed and cannot be translated, but the wrist can be adjusted in different postures to carry out objects. the fetch; Step 1 (2), each subject adjusts the wrist to different postures to complete the grasping of 6 objects located in 27 relative positions relative to the front, middle, back, left, middle and right, and upper, middle, and lower of the human hand. Each object is grasped twice ; Step 1 (3), establishing a human hand grasping gesture library, which includes 27×2×6×10=3240 grasping gestures. 3. according to claim 1, the finger module division method based on the analysis of the human hand motion function is characterized in that: in the step 2, the analysis of the kinematic characteristics of the joint itself is used to omit the degree of freedom of joint angles in different grasps, and on this basis, Only the four-finger metacarpophalangeal joint abduction-adduction, metacarpophalangeal joint extension-flexion and interphalangeal joint extension-flexion are analyzed for joint motion characteristics. Compared with different grasps, the abduction and adduction joint angle of the four fingers of the human hand does not change much, and the consistency is strong. Therefore, the degrees of freedom of the abduction and adduction joints of the four fingers of the human hand are omitted, and the four fingers of the human hand are retained. Metacarpophalangeal extension-flexion joints, interphalangeal extension-flexion joints, the order of joint angle changes in different grasps is: metacarpophalangeal extension-flexion joints are greater than interphalangeal extension-flexion joints are much greater than metacarpophalangeal abduction-adduction, so , the number of coupling modules corresponding to the metacarpophalangeal extension-flexion joint should be less than that of the interphalangeal extension-flexion joint. 4. according to claim 1, based on the finger module division method of human hand motion function analysis, it is characterized in that: in the step 3, analyze the kinematic characteristics between joints for dividing the joint degrees of freedom reserved into modules, and to retain the joint degrees of freedom Under the correlation analysis, one pair and two pairs of joints with high correlation were identified in the metacarpophalangeal extension-flexion joints and interphalangeal extension-flexion joints, respectively. 5. according to claim 1, based on the finger module division method of human hand movement function analysis, it is characterized in that: in the step 4, analyzing the relevant proportional coefficient is used to determine the active degree of freedom of each module, when the active degree of freedom in each coupling module When is the joint corresponding to the red point, the coupling coefficients of the three coupled drive modules have very little difference, so the red point in each coupled drive module is selected as the active degree of freedom of the coupled drive module. 6. according to claim 1, based on the finger module division method of human hand motion function analysis, it is characterized in that: in the step 5, analyze the anatomy of the hand and the frequency of use of each finger in different grabs for the analysis basis of the reference correlation proportional coefficient The active degrees of freedom of the coupled modules are finally determined on .