CN104665962A - Wearable function-enhanced manipulator system as well as assisting fingers and control method thereof - Google Patents

Abstract

The invention provides a wearable function-enhanced manipulator system and assisting fingers thereof. Assisting fingers adopt rope drive; force sensing is formed by using a spring connected with a driving rope; an annular electromyography acquiring array is worn on a forearm of a user and is used for estimating motion and force information of the wrist and fingers of the user, and estimating the behavior intention of the user according to the extracted position and the force information, so that a corresponding decision is made for assisting or enhancing the activity function of the fingers; a passive arm mechanism shares forces borne by the wrist and the fingers of a human body and can realize the actions of assisting and enhancing the function of the fingers under the condition that normal activities of the human body are not influenced. Meanwhile, the invention provides a control method for the manipulator system. The wearable function-enhanced manipulator system has the advantages of compact structure, light weight, good flexibility and good safety; the functions of the fingers can be enhanced to the maximum extent, and natural hands of the user are enabled to engage other tasks; the wearable function-enhanced manipulator system has better use potential in the industry, agriculture, household demand, entertainment and other aspects.

Description

Wearable function strengthens machine hand system and assisted finger thereof and control method

Technical field

The present invention relates to wearable robot system, specifically a kind of wearable function based on myoelectricity interface strengthens machine hand system and assisted finger thereof and control method, to strengthen singlehanded function.

Background technology

Wearable device and man-machine coordination robotics day by day become study hotspot in the last few years, by means of the function etc. that people natively has, Wearable device such as exoskeleton robot can make man-machine compatibility, be widely used in power-assisted, rehabilitation, the fields such as amusement, strengthen or have expanded Personal Skills, and man-machine coordination operation is more closely with practical.

There is Wearable device miscellaneous at present, strength support is mainly provided or assists.But not only provided power-assisted but can man-machine coordination to complete the equipment of a certain task actually rare, although single power assistive device or rehabilitation equipment serve power-assisted effect, also likely limit the performance of other functions, other power assistive device is because volume is large, can bring inconvenience to the activity space of people, thus, the wearable device of dexterous type, both demand fulfillment power-assisted demand, also the requirement of demand fulfillment man-machine coordination, also need volume little in addition, energy consumption, cost is low.

Through finding existing technical literature retrieval:

Chinese utility model patent publication number: CN 202537871 U, title: a kind of hand and wrist exoskeleton rehabilitation training device.This ectoskeleton equipment is mainly used in rehabilitation, and equipped with booster, but power assisting device is only fixed on forearm, can produce extra heavy burden, do not utilize life-time service to the ancon of people.

Chinese utility model patent publication number: CN 200954207 Y, title: a kind of based on ectoskeletal arm rehabilitation device.Provide a kind of exercising apparatus for recovery of upper limb, but mechanism is complicated, portability is poor, and control mode is single, the behavior of real-time assessment human body cannot be intended to, can not provide man-machine coordination decision-making, be unfavorable for user operation.

Summary of the invention

The present invention is directed to the deficiency that prior art exists, provide a kind of wearable function based on myoelectricity control strategy to strengthen machine hand system and assisted finger thereof and control method, not only for power-assisted, and for man-machine coordination operation.

The present invention is achieved by the following technical solutions.

According to an aspect of the present invention, provide a kind of assisted finger, comprise imitation human finger, finger base, motor a2, motor a3, motor a4, wherein, described imitation human finger adopts and drives rope to drive, and has clamping DOF, bend and stretch degree of freedom and reclaim degree of freedom three degree of freedom; Described motor a4 directly drives with imitation human finger and is connected, for realizing the recovery degree of freedom of imitation human finger; The rotating shaft of described motor a4 is connected with decelerator, the output shaft of described decelerator is connected with one for realizing the rotating shaft of imitation human finger clamping DOF, described imitation human finger to be restricted connection rotating shaft and drive motors a2 successively by driving, and described rotating shaft drives with drive motors a2 and is connected; Described imitation human finger passes through to drive rope to drive with motor a3 and is connected, for realizing the bending degree of freedom of imitation human finger;

Described imitation human finger is connected in finger base; Described finger base comprises panel installed surface c2, wrist adapter c3 and modularized joint interface c1, wherein:

Described panel installed surface c2 is provided with control panel, described control panel and motor a2, motor a3, motor a4 control connection;

Described wrist adapter c3 is provided with user's wrist;

Described modularized joint interface c1 is provided with Three Degree Of Freedom modularized joint;

Annexation or the driving relationship of described modularized joint interface c1, panel installed surface c2, wrist adapter c3 and imitation human finger are specially: described modularized joint interface c1 is provided with joint adpting flange, and described Three Degree Of Freedom modularity is fastenedly connected by joint adpting flange and finger base; Described user's wrist is provided with at least one user's wrist geometry adaptable interface, by the adaptive different user demands of adjustment interface radius; Described panel installed surface c2 is provided with the screwed hole connected for control panel; Described imitation human finger is connected with Three Degree Of Freedom modularized joint by driving rope, pretension parts and finger adpting flange, makes it move.

Preferably, described motor a2, motor a3 and motor a4 are respectively equipped with code-disc, for controlling the position of imitation human finger.

Preferably, the drive pulley p1 that restricts is provided with between described rotating shaft and drive motors a2; The drive pulley p2 that restricts is provided with between described imitation human finger and drive motors a3; Rope drive pulley p1 and rope drive pulley p2 walked around respectively by described driving rope, and forms closed-loop path respectively;

Described rope drive pulley p1 and rope drive pulley p2 is separately fixed in rotating shaft.

Preferably, described assisted finger also comprises: position sensor and force transducer, wherein:

Each finger-joint of described apery and finger thereof being equipped with a position sensor, for detecting finger-joint positional information, and then obtaining the angle of bend of each finger-joint;

Described force transducer comprise with drive restrict the spring that is connected and for detection springs be out of shape produce the linear potentiometer of current potential, obtained the deflection of spring by the current potential detected, and then obtain the size of each finger-joint power/moment.

Preferably, described imitation human finger comprises symmetrically arranged two bar linkage structures, and wherein, each root bar linkage structure includes first connecting rod and second connecting rod, is connected between described first connecting rod and second connecting rod by articulated manner.

According to a second aspect of the invention, provide a kind of wearable function and strengthen machine hand system, before comprising self adaptation, arm coupling b1, upper arm link b2, forearm link b4, annular myoelectricity gather array and above-mentioned assisted finger, wherein:

Before described self adaptation, arm coupling b1 is connected with upper arm link b2 by ball-joint, described upper arm link b2 is connected with forearm link b4 by linkwork b3, and described forearm link b4 is connected with the wrist adapter c3 of assisted finger finger base by ball-joint interface b5;

Described annular myoelectricity gathers array and is arranged in forearm link;

The adjustable in length of described upper arm link b2 and forearm link b4.

Preferably, the rotating shaft of described linkwork b3 is provided with code-disc, for recording human body ancon positional information, for structure people and the coordination system provide input information.

According to a third aspect of the present invention, provide the control method that a kind of wearable function strengthens machine hand system, adopt Isometric (isometric contraction) control mode based on myoelectricity, under but user hand does not move and there is muscle contraction situation, by the electromyographic signal that annular myoelectricity collection array acquisition arrives, through pattern recognition, judge user motion intention, realize preliminary gesture and control.

Preferably, also comprise the steps: by assessing and continuous estimation the rigidity of imitation human finger, the impedance Control and the continuous position that realize imitation human finger control, and the angle of bend of each finger-joint that the code-disc of each finger-joint power/moment obtained with force transducer and motor a2, motor a3 and motor a4 controls, build specific man-machine coordination control strategy.

Preferably, described impedance Control is specially: the electromyographic signal that the force information obtained by force transducer and annular myoelectricity gather array acquisition carries out information fusion, to obtain corresponding rigidity sequence, and pointing rigidity for controlling, realizing man-machine coordination and controlling;

Described continuous position controls to be specially: based on the continuous estimation of electromyographic signal, build based on the linear relationship between finger-joint angle of bend and electromyographic signal.

The operation principle of invention is: assisted finger adopts tendon (driving rope) to drive, and collapsible, each joint position sensor, for detecting joint position information; And the Force sensor utilizing the spring that is connected of restricting with driving to make deformation based to measure, it estimates each joint power/moment size according to the distortion of spring; Annular myoelectricity gathers array and is worn on user forearm, for estimated service life person's wrist and the motion of finger and the information of power, and the behavior intention to user is assessed according to the position of extracting and force information, thus make corresponding decision-making, auxiliary or enhancing finger movement function.Passive type arm mechanism comprises: arm coupling, upper arm link, forearm link before self adaptation; for sharing human body wrist and pointing the power of bearing; be connected with wrist adapter by ball-joint; forearm and upper arm is connected by articulated manner; thus when not affecting human normal activity, the effect of power-assisted and enhancing finger function can be played.

Compared with prior art, the present invention has following beneficial effect:

1, imitation human finger adopts rope to drive, and has three degree of freedom, is realized, reduce the weight and volume of finger, have light, dexterous feature by modularized joint interface c1, is applicable to wearing for a long time.

2, three degree of freedom is allocated as follows: a clamping DOF, for gripping objects; A finger flex degree of freedom, for adapting to different contour of object and increasing the space pointed; One is reclaimed degree of freedom, so that when finger does not work, the forearm along people folds, and minimizing takes up room.

3, the adjustable length of upper arm link and forearm link, to adapt to the long user's request of different elbow.

4, wearable function strengthens machine hand system compact conformation, and lightweight, compliance, safety is good, can strengthen hand function to greatest extent, thus the natural hand of user can be made to be engaged in other tasks.

5, wearable function strengthens machine hand system, adopts myoelectricity control mode, and the electromyographic signal that the force information obtained by force transducer and myoelectricity gather array acquisition carries out information fusion, realizes man-machine coordination and controls, be convenient to user control operation.

6, the present invention is with a wide range of applications in industry, agricultural, domestic, amusement etc.

Accompanying drawing explanation

By reading the detailed description done non-limiting example with reference to the following drawings, other features, objects and advantages of the present invention will become more obvious:

Fig. 1 is that the wearable function of the present invention strengthens machine hand system overall structure schematic diagram;

Fig. 2 is wrist-elbow boosting mechanism figure;

Fig. 3 is the motor setting up structure figure realizing Three Degree Of Freedom;

Fig. 4 is finger base exploded view;

Fig. 5 is the monotroded bar structural representation of imitation human finger;

Fig. 6 is for driving rope wiring diagram;

Fig. 7 is that position sensor, force transducer and annular myoelectricity gather array functional figure;

Fig. 8 always schemes based on the control mode of myoelectricity;

Fig. 9 adopts the Isometric control method flow chart based on myoelectricity;

Figure 10 is continuous position control method flow chart.

In figure: 1 is first connecting rod, 2 is second connecting rod, a1 is first connecting rod drive pulley, a2 is motor a2, a3 is motor a3, a4 is motor a4, a5 is motor a2 driver, a6 is motor a4 controller, a7 is motor a3 controller, a8 is that myoelectricity gathers array, b1 is arm coupling b1 before self adaptation, b2 is upper arm link b2, b3 is linkwork b3, b4 is forearm link b4, b5 is ball-joint interface b5, p1 is rope drive pulley p1, p2 restricts drive pulley p2 respectively, c1 is modularized joint interface c1, c2 is panel installed surface c2, c3 is wrist adapter c3, d1 is that rope drives pre-bearing up pulley, j1 is finger first joint, j2 is finger second joint, j3 is finger the 3rd joint.

Detailed description of the invention

Below embodiments of the invention are elaborated: the present embodiment is implemented under premised on technical solution of the present invention, give detailed embodiment and concrete operating process.It should be pointed out that to those skilled in the art, without departing from the inventive concept of the premise, can also make some distortion and improvement, these all belong to protection scope of the present invention.

Embodiment 1

Present embodiments provide a kind of assisted finger, comprise imitation human finger, finger base, motor a2, motor a3, motor a4, wherein, described imitation human finger adopts and drives rope to drive, and has clamping DOF, bend and stretch degree of freedom and reclaim degree of freedom three degree of freedom; Described motor a4 directly drives with imitation human finger and is connected, for realizing the recovery degree of freedom of imitation human finger; The rotating shaft of described motor a4 is connected with decelerator, the output shaft of described decelerator is connected with one for realizing the rotating shaft of imitation human finger clamping DOF, described imitation human finger to be restricted connection rotating shaft and drive motors a2 successively by driving, and described rotating shaft drives with drive motors a2 and is connected; Described imitation human finger passes through to drive rope to drive with motor a3 and is connected, for realizing the bending degree of freedom of imitation human finger;

Described imitation human finger is connected in finger base; Described finger base comprises panel installed surface c2, wrist adapter c3 and modularized joint interface c1, wherein:

Described panel installed surface c2 is provided with control panel, described control panel and motor a2, motor a3, motor a4 control connection;

Described wrist adapter c3 is provided with user's wrist;

Described modularized joint interface c1 is provided with Three Degree Of Freedom modularized joint;

Annexation or the driving relationship of described modularized joint interface c1, panel installed surface c2, wrist adapter c3 and imitation human finger are specially: described modularized joint interface c1 is provided with joint adpting flange, and described Three Degree Of Freedom modularity is fastenedly connected by joint adpting flange and finger base; Described user's wrist is provided with at least one user's wrist geometry adaptable interface, by the adaptive different user demands of adjustment interface radius; Described panel installed surface c2 is provided with the screwed hole connected for control panel; Described imitation human finger is connected with Three Degree Of Freedom modularized joint by driving rope, pretension parts and finger adpting flange, makes it move.

Further, described motor a2, motor a3 and motor a4 are respectively equipped with code-disc, for controlling the position of imitation human finger.

Further, the drive pulley p1 that restricts is provided with between described rotating shaft and drive motors a2; The drive pulley p2 that restricts is provided with between described imitation human finger and drive motors a3; Rope drive pulley p1 and rope drive pulley p2 walked around respectively by described driving rope, and forms closed-loop path respectively;

Described rope drive pulley p1 and rope drive pulley p2 is separately fixed in rotating shaft.

Further, described assisted finger also comprises: position sensor and force transducer, wherein:

Each finger-joint of described apery and finger thereof being equipped with a position sensor, for detecting finger-joint positional information, and then obtaining the angle of bend of each finger-joint;

Described force transducer comprise with drive restrict the spring that is connected and for detection springs be out of shape produce the linear potentiometer of current potential, obtained the deflection of spring by the current potential detected, and then obtain the size of each finger-joint power/moment.

Further, described imitation human finger comprises symmetrically arranged two bar linkage structures, and wherein, each root bar linkage structure includes first connecting rod and second connecting rod, is connected between described first connecting rod and second connecting rod by articulated manner.

In the present embodiment:

Imitation human finger adopts rope to drive, and has three degree of freedom, is realized, reduce the weight and volume of finger by modularized joint interface c1, light, dexterous.

Three degree of freedom is allocated as follows: a clamping DOF, for gripping objects; A finger flex degree of freedom, for adapting to different contour of object and increasing the space pointed; One is reclaimed degree of freedom, so that when finger does not work, the forearm along people folds, and minimizing takes up room.

The implementation of three degree of freedom is as follows: motor a4 Direct driver is pointed, and is mainly used in folding finger and expands the space pointed; Connection reducer in the rotating shaft of a4 motor, reducer output shaft connects a rotating shaft for clamping DOF, and realized by rope drive pulley p1, drive motors is a2; Motor a3 connects pulley p2, for the curvature movement pointed, three described motors is all equipped with code-disc, for controlling the position pointed.

Finger base as shown in Figure 4, comprises panel installed surface c2, wrist adapter c3, modularized joint interface c1.

Force transducer comprises spring and potentiometer, and spring is connected to and drives on rope, and the actuator of force transducer is spring, the current potential produced by the distortion of potentiometer detection springs, and then obtains the deflection of spring, obtains the size of the power/moment of imitation human finger.

Drive the winding mode of rope as shown in Figure 6, often kind of winding mode all forms a closed-loop path, completes a kind of motion of imitation human finger.

The first connecting rod of each root bar linkage structure of imitation human finger is connected by articulated manner with second connecting rod, static line drive pulley in rotating shaft, is realized the motion of bar linkage structure by the coiling of rope drive pulley.

Embodiment 2

Present embodiments provide a kind of wearable function and strengthen machine hand system, the assisted finger that before comprising self adaptation, arm coupling b1, upper arm link b2, forearm link b4, annular myoelectricity collection array and embodiment 1 provide, wherein:

Before described self adaptation, arm coupling b1 is connected with upper arm link b2 by ball-joint, described upper arm link b2 is connected with forearm link b4 by linkwork b3, and described forearm link b4 is connected with the wrist adapter c3 of assisted finger finger base by ball-joint interface b5;

Described annular myoelectricity gathers array and is arranged in forearm link;

The adjustable in length of described upper arm link b2 and forearm link b4.

Further, the rotating shaft of described linkwork b3 is provided with code-disc, for recording human body ancon positional information, for structure people and the coordination system provide input information.

The wearable function that the present embodiment provides strengthens machine hand system, its control method, adopt Isometric (isometric contraction) control mode based on myoelectricity, under but user hand does not move and there is muscle contraction situation, by the electromyographic signal that annular myoelectricity collection array acquisition arrives, through pattern recognition, judge user motion intention, realize preliminary gesture and control.

Further, also comprise the steps: by assessing and continuous estimation the rigidity of imitation human finger, the impedance Control and the continuous position that realize imitation human finger control, and the angle of bend of each finger-joint that the code-disc of each finger-joint power/moment obtained with force transducer and motor a2, motor a3 and motor a4 controls, build specific man-machine coordination control strategy.

Further, described impedance Control is specially: the electromyographic signal that the force information obtained by force transducer and annular myoelectricity gather array acquisition carries out information fusion, to obtain corresponding rigidity sequence, and pointing rigidity for controlling, realizing man-machine coordination and controlling;

Described continuous position controls to be specially: based on the continuous estimation of electromyographic signal, build based on the linear relationship between finger-joint angle of bend and electromyographic signal.

The control method that the present embodiment provides comprises following three kinds of control models:

-simple gesture control model:

By the gesture identification of electromyographic signal, obtain user's hand gesture, as the control signal of mechanical finger, realize simple switching manipulation, as folding, the actions such as pitching.Its control principle as shown in Figure 9.

In Fig. 9, signal segmentation method is, the electromyographic signal detected is divided into the folded window of 200ms length, and increasing lengths is 50ms; Feature extraction adopts time domain autoregression characteristic model parameter, or the feature such as wavelength WL (Waveform Length), average absolute value MAV (Mean Absolute Value).Feature Dimension Reduction adopts PCA PCA (Principal Component Analysis), and sorting algorithm adopts Fisher face LDA (Linear Discriminative Analysis).

-continuous position control model:

This pattern is based on the continuous estimation of electromyographic signal, and its model is based on the movement angle in joint and electromyographic signal linear approximate relationship.Control flow as shown in Figure 10.In figure, formula is followed successively by:

$\mathrm{IEMG}=\underset{t_l}{\overset{t_l+t_0}{\mathrm{\Σ}}}\left|{\mathrm{EMG}}_t\right|$

$\mathrm{AIEMG}\left(k\right)=\frac{1}{N}\underset{t=0}{\overset{N-1}{\mathrm{\Σ}}}\left|\mathrm{IEMG}\left(t\right)\right|$

$V\left(m\right)=\frac{1}{L}\underset{t=1}{\overset{L}{\mathrm{\Σ}}}\mathrm{AIEMG}\left(m\right)$

$\widehat{\mathrm{\θ}}=\frac{V\left(m\right)-V_{\mathrm{ij}}^{\min }}{V_{\mathrm{ij}}^{\max }-V_{\mathrm{ij}}^{\min }}{\mathrm{\θ}}_{\mathrm{ij}}^{\max }$

In conjunction with Figure 10, the N in formula represents the sampling number in a frame, and t represents at t sampled point, and k represents a kth average frame. represent the limit of sports record position of finger-joint on three degree of freedom respectively, i represents joint classification, and j represents corresponding joint motions classification, t ₁for window time interval, t ₀for zero computing time.

-force control mode:

Power Controlling model is based on muscle-Li Hill model, and power algorithm for estimating is as follows:

$F=F^t=F_{\max }[F_A\left(l_m\right)*F_V\left({\hat{V}}_m\right)*a\left(t\right)+{\hat{F}}_p\left(l_m\right)]\cos \mathrm{\φ}$

Wherein:

F ^t: the power that tendon produces;

A (t): muscle drive volume;

F _max: muscle equal length shrinks maximum, force;

F _a(l _m): active force and muscle relation;

muscle-length velocity relation;

φ: tendon and meat fiber angle;

F _a: active force;

L _m: muscle length;

F _v: muscle-speed power;

movement velocity;

by power and muscle relation;

by power.

Below control method is further described:

User has dressed wearable function and has strengthened machine hand system, and when human body produces motion, produce electromyographic signal, signal passes to computer by wireless blue tooth thereupon, and signal processing realizes through following several mode:

(1) by pattern recognition, obtain human body gesture, can be used for carrying out the operations such as such as folding;

(2) by continuous locomotion evaluation, obtain human finger articulated position and speed, build the relative space position relation of robot finger and human finger, by the identification of human eye to object, realize capturing the singlehanded task that can not complete, as one hand grabs basketball, football etc.

(3) by extracting the impedance information of electromyographic signal, realize the impedance Control of robot finger, thus coordinate the change of human arm direct impedance, coordinate man-computer cooperation.

(4) by the fusion of electromyographic signal and robot finger's positional information and force information, build human computer cooperation system, be that human body behavior intention is understood by robot, realize the intellectuality of robot.

The wearable function that the present embodiment provides strengthens machine hand system, solve in commercial production and depend on merely the problem that hand causes wrist muscle fatigue for a long time, by adopting passive type boosting mechanism (before self adaptation arm coupling b1, upper arm link b2, forearm link b4), make hand load balancing to human body upper arm, the operating pressure of effective alleviation hand, owing to adopting passive type power-assisted, without the need to power supply, thus decrease the weight and volume of robot arm system ontology, make the lightweight of whole robot arm system.

Above specific embodiments of the invention are described.It is to be appreciated that the present invention is not limited to above-mentioned particular implementation, those skilled in the art can make various distortion or amendment within the scope of the claims, and this does not affect flesh and blood of the present invention.

Claims (10)

1. an assisted finger, is characterized in that, comprises imitation human finger, finger base, motor a2, motor a3, motor a4, and wherein, described imitation human finger adopts and drives rope to drive, and has clamping DOF, bend and stretch degree of freedom and reclaim degree of freedom three degree of freedom; Described motor a4 directly drives with imitation human finger and is connected, for realizing the recovery degree of freedom of imitation human finger; The rotating shaft of described motor a4 is connected with decelerator, the output shaft of described decelerator is connected with one for realizing the rotating shaft of imitation human finger clamping DOF, described imitation human finger to be restricted connection rotating shaft and drive motors a2 successively by driving, and described rotating shaft drives with drive motors a2 and is connected; Described imitation human finger passes through to drive rope to drive with motor a3 and is connected, for realizing the bending degree of freedom of imitation human finger;

Described imitation human finger is connected in finger base; Described finger base is provided with panel installed surface c2, wrist adapter c3 and modularized joint interface c1, wherein:

Described panel installed surface c2 is provided with control panel, described control panel and motor a2, motor a3, motor a4 control connection;

Described wrist adapter c3 is provided with user's wrist;

Described modularized joint interface c1 is provided with Three Degree Of Freedom modularized joint;

Described modularized joint interface c1 is provided with joint adpting flange, and described Three Degree Of Freedom modularity is fastenedly connected by joint adpting flange and finger base; Described user's wrist is provided with at least one user's wrist geometry adaptable interface; Described imitation human finger is connected with Three Degree Of Freedom modularized joint by driving rope, pretension parts and finger adpting flange.

2. assisted finger according to claim 1, is characterized in that, described motor a2, motor a3 and motor a4 are respectively equipped with code-disc, for controlling the position of imitation human finger.

3. assisted finger according to claim 1, is characterized in that, is provided with the drive pulley p1 that restricts between described rotating shaft and drive motors a2; The drive pulley p2 that restricts is provided with between described imitation human finger and drive motors a3; Rope drive pulley p1 and rope drive pulley p2 walked around respectively by described driving rope, and forms closed-loop path respectively;

Described rope drive pulley p1 and rope drive pulley p2 is separately fixed in rotating shaft.

4. assisted finger according to claim 1, is characterized in that, described assisted finger also comprises: position sensor and force transducer, wherein:

Each finger-joint of described apery and finger thereof being equipped with a position sensor, for detecting finger-joint positional information, and then obtaining the angle of bend of each finger-joint;

Described force transducer comprise with drive restrict the spring that is connected and for detection springs be out of shape produce the linear potentiometer of current potential, obtained the deflection of spring by the current potential detected, and then obtain the size of each finger-joint power/moment.

5. assisted finger according to any one of claim 1 to 4, it is characterized in that, described imitation human finger comprises symmetrically arranged two bar linkage structures, wherein, each root bar linkage structure includes first connecting rod and second connecting rod, is connected between described first connecting rod and second connecting rod by articulated manner.

6. wearable function strengthens a machine hand system, it is characterized in that, before comprising self adaptation, arm coupling b1, upper arm link b2, forearm link b4, annular myoelectricity gather array and the assisted finger according to any one of claim 1 to 5, wherein:

Before described self adaptation, arm coupling b1 is connected with upper arm link b2 by ball-joint, described upper arm link b2 is connected with forearm link b4 by linkwork b3, and described forearm link b4 is connected with the wrist adapter c3 of assisted finger finger base by ball-joint interface b5;

Described annular myoelectricity gathers array and is arranged in forearm link;

The adjustable in length of described upper arm link b2 and forearm link b4.

7. wearable function according to claim 6 strengthens machine hand system, and it is characterized in that, the rotating shaft of described linkwork b3 is provided with code-disc, for recording human body ancon positional information.

8. the control method of a wearable function enhancing machine hand system, it is characterized in that, adopt the isometric contraction control mode based on myoelectricity, under but user hand does not move and there is muscle contraction situation, by the electromyographic signal that annular myoelectricity collection array acquisition arrives, through pattern recognition, judge user motion intention, realize preliminary gesture and control.

9. wearable function according to claim 8 strengthens the control method of machine hand system, it is characterized in that, also comprise the steps: by assessing and continuous estimation the rigidity of imitation human finger, the impedance Control and the continuous position that realize imitation human finger control, and the angle of bend of each finger-joint that the code-disc of each finger-joint power/moment obtained with force transducer and motor a2, motor a3 and motor a4 controls, build specific man-machine coordination control strategy.

10. wearable function according to claim 9 strengthens the control method of machine hand system, it is characterized in that, described impedance Control is specially: the electromyographic signal that the force information obtained by force transducer and annular myoelectricity gather array acquisition carries out information fusion, to obtain corresponding rigidity sequence, and point rigidity for controlling, realize man-machine coordination and control;

Described continuous position controls to be specially: based on the continuous estimation of electromyographic signal, build based on the linear relationship between finger-joint angle of bend and electromyographic signal.