Two degrees of freedom EMG-controlling prosthetic hand real-time control apparatus and control method
Technical field
The invention belongs to information and control technology field, relate to a kind of technology that myoelectric information control is manually done evil through another person, specifically is two degrees of freedom EMG-controlling prosthetic hand real-time control apparatus and control method.
Background technology
Electromyographic signal (Electromyography, abbreviation EMG) is a kind of bioelectrical signals of following musculation, is the signal of telecommunication root of musculation, has wherein contained the various information of musculation, comprises and the corresponding limb action pattern of musculation.Surface electromyogram signal (SurfaceElectromyography, abbreviation SEMG) then be on the EMG of shallow-layer muscle and the nerve trunk electrical activity at the comprehensive effect of skin surface.Because SEMG has the non-intruding characteristic on measuring, the individuality that is implemented detection is had no pain and characteristics easily, obtained application widely at numerous areas such as clinical medicine, sports medical science.
Obtain SEMG on the residual arm of hand amputee by surperficial power-collecting electrode, SEMG is carried out pattern information handle the action pattern that can obtain hand, can reach the do evil through another person purpose of control of myoelectricity man power according to the mode treatment result.The control that SEMG is the amputee by deformed limb and mechanical prosthetic hand connects, and realizes the bridge of its control intention.For the people with disability of the limbs disappearance day after tomorrow, still have limbs control consciousness generally speaking as the sound healthy people of limbs, medically be referred to as " phantom limb sense ".The wearer of EMG-controlling prosthetic hand utilizes this sensation just, controls the musculation of deformed limb by the mode that similar healthy people controls limb action, and then reaches the purpose to the control of doing evil through another person.So the myoelectricity powered artificial hand has action nature, characteristics that bionical performance is good, has been subjected to increasing concern.
The EMG-controlling prosthetic hand of single-degree-of-freedom is generally controlled powered artificial hand by the SEMG that picks up a pair of Antagonistic muscle of amputee's stump (as wrist protractor and wrist musculus flexor), with the positive and negative rotation of drive motors opening of realizing doing evil through another person with close up.As, when the SEMG of wrist protractor intensity reaches preset threshold, control motor forward rotation, vice versa.Thisly control the method for a motor positive and inverse respectively with the two-way electromyographic signal, reliable operation is used widely.The I of Tsing-Hua University type single-degree-of-freedom EMG-controlling prosthetic hand as people's developments such as, royal people become.Multi-freedom artificial limb need extract multivariant action pattern information usually from the SEMG of few passage, discrimination is difficult to reach 100%.1978, people such as Herberts developed multi-functional EMG-controlling prosthetic hand, utilized amputee's hallucination and based on the many action patterns identification of SEMG, controlled one and did evil through another person and finish the action of 3 degree of freedom, and the accuracy rate of action is 57%.After people's such as Denning improvement, the recognition correct rate that 3DOF is done evil through another person brings up to 72%.After 2000, the discrimination of multi-freedom degree muscle-electric artificial hand reaches more than 85%, but owing to still have certain misclassification rate, still has with a certain distance from practicality.At present, commercial multiple freedom degrees hand-prosthesis generally adopts sequential control mode (or switch switching mode) to realize the control of multi-freedom artificial limb, as, control is opened during the wrist protractor contraction, and control was closed up when the wrist musculus flexor shrank, wrist protractor, realization control sequence switching when the wrist musculus flexor shrinks (clenching fist) simultaneously, at this moment, wrist protractor control wrist is left-handed, and the dextrorotation of wrist musculus flexor control wrist realizes multivariant control by that analogy.Though utilize this method can realize the control of multi-freedom artificial limb, this method is because exist inconvenient operation, lack shortcomings such as real-time and bionical poor performance, thus on market, use and few.
Summary of the invention
Purpose of the present invention is exactly at the deficiencies in the prior art, provide a kind of accuracy rate height, bionical performance good, can control the control device of two degrees of freedom EMG-controlling prosthetic hand in real time, make its control device of finishing four actions of doing evil through another person, the control method of this device is provided simultaneously.
The present invention realizes four of the two degrees of freedom EMG-controlling prosthetic hand actions of doing evil through another person by receiving the corresponding SEMG of three vastus meat (extensor carpi ulnaris m., flexor carpi ulnaris m. and extensor digitorum).Four actions refer to opening of doing evil through another person, close up, wrist is stretched, wrist is bent; During no sports consciousness, three vastus meat are in relaxed state, do evil through another person and are failure to actuate.
The technical scheme of control device of the present invention: comprise that three myoelectricities that are contained on the residual arm pick up electric transducer, each myoelectricity picks up the elementary amplifying circuit that electric transducer comprises three power-collecting electrodes and the localityization that is connected with the power-collecting electrode signal, and three power-collecting electrodes are respectively anelectrode, negative electrode and ground electrode.The outfan of three elementary amplifying circuits connects with the input of corresponding back level amplification filtering circuit respectively, and the outfan of level amplification filtering circuit is connected with the input of A/D change-over circuit after three.Two motors of two degrees of freedom EMG-controlling prosthetic hand connect with corresponding drive circuit respectively.Single-chip microcomputer is connected with the outfan of A/D change-over circuit, the input end signal of drive circuit respectively.
The drive circuit that myoelectricity among the present invention picks up electric transducer, back level amplification filtering circuit, A/D change-over circuit, single-chip microcomputer, motor all adopts existing single-degree-of-freedom EMG-controlling prosthetic hand corresponding devices.
The control method of this two degrees of freedom EMG-controlling prosthetic hand real-time control apparatus: three myoelectricities pick up the SEMG that electric transducer is gathered extensor carpi ulnaris m., flexor carpi ulnaris m. and extensor digitorum's correspondence from human body respectively, in input single-chip microcomputer after amplification, filtering, the A/D conversion process; Single-chip microcomputer judges the SEMG power after handling, and exports four tunnel control signals, drives the motor of two degrees of freedom electrically powered hand through drive circuit, finishes four actions of two degrees of freedom electrically powered hand.
Single-chip microcomputer judges it is power combination by three road SEMG of extensor carpi ulnaris m., flexor carpi ulnaris m., extensor digitorum's correspondence to the SEMG after handling is strong and weak, and artificial hand controlled is opened, closed up, wrist is stretched, wrist is bent four actions.The strong and weak combination of three road SEMG with the corresponding relation of four actions is: the SEMG of extensor digitorum is strong, and the motor of control two degrees of freedom EMG-controlling prosthetic hand is done evil through another person and opened; Extensor carpi ulnaris m. SEMG is strong, flexor carpi ulnaris m. SEMG is strong, and the motor of control two degrees of freedom EMG-controlling prosthetic hand is done evil through another person and closed up; Extensor carpi ulnaris m. SEMG is strong, a little less than the flexor carpi ulnaris m. SEMG, the motor of control two degrees of freedom EMG-controlling prosthetic hand is done and is stretched the wrist action; Flexor carpi ulnaris m. SEMG is strong, a little less than the extensor carpi ulnaris m. SEMG, the motor of control two degrees of freedom EMG-controlling prosthetic hand is done and is bent the wrist action; The SEMG of extensor digitorum is weak, extensor carpi ulnaris m. SEMG weak, a little less than the flexor carpi ulnaris m. SEMG, do evil through another person and be failure to actuate.
The strong and weak evaluation algorithm of SEMG can be by to the adding up of SEMG amplitude, or absolute value adds up, or method such as variance size is judged that effectively these methods all are existing conventional method (for example using in the control of single-degree-of-freedom EMG-controlling prosthetic hand).
The hand multi-locomotion mode identification that the present invention is based on SEMG is to realize by the signal power of judging SEMG, the accuracy of identification reaches 100%, action control is reliable, avoid the multi-freedom degree muscle-electric artificial hand of conventional commercial need be by switching the situation just can reach the control of multiple freedom degrees hand-prosthesis, realized the do evil through another person real-time control of four actions of two degrees of freedom under the highly reliable discrimination, the bionical ability of multiple freedom degrees hand-prosthesis control is greatly improved.
Description of drawings
Fig. 1 is the structural representation of apparatus of the present invention;
Fig. 2 is for picking up the structure chart of electric transducer among Fig. 1.
The specific embodiment
With reference to the description of drawings embodiments of the present invention.
The present invention as depicted in figs. 1 and 2, two degrees of freedom EMG-controlling prosthetic hand real-time control apparatus comprises that three myoelectricities at extensor carpi ulnaris m., flexor carpi ulnaris m., the extensor digitorum pairing skin surface place that is positioned over the residual arm of people with disability respectively pick up electric transducer 1.Each myoelectricity picks up 8, three power-collecting electrodes 7 of elementary amplifying circuit that electric transducer 1 comprises three power-collecting electrodes 7 and the localityization that is connected with power-collecting electrode 7 signals and is respectively anelectrode, negative electrode and ground electrode.Power-collecting electrode 7, elementary amplifying circuit 8 that myoelectricity picks up electric transducer 1 structurally are incorporate, power-collecting electrode 7 is rectangle gold plated copper electrodes, its size and shape is with conventional to be applied to the electrode that SEMG picks up the same, elementary amplifying circuit 8 adopts conventional instrumentation amplifier, elementary amplifying circuit 8 places after the power-collecting electrode, is packaged together by a plastic casing.Elementary amplifying circuit 8 and the power-collecting electrode 7 integrated signal to noise ratios that help improving SEMG.The outfan of three elementary amplifying circuits 8 connects with the input of corresponding back level amplification filtering circuit 2 respectively, and the outfan of level amplification filtering circuit 2 is connected with the input of A/D change-over circuit 3 after three.Two motors 6 of two degrees of freedom EMG-controlling prosthetic hand connect with corresponding drive circuit 5 respectively.Single-chip microcomputer 4 is connected with the outfan of A/D change-over circuit 3, the input end signal of drive circuit 5 respectively.The drive circuit 5 of the back level amplification filtering circuit 2 in this device, A/D change-over circuit 3, single-chip microcomputer 4, motor all adopts existing single-degree-of-freedom EMG-controlling prosthetic hand corresponding devices.
By myoelectricity pick up SEMG that electric transducer 1 picks up through amplifying circuit, Filtering Processing circuit, the collection of A/D translation data, single-chip microcomputer finish the opening of the motion of doing evil through another person, close up, wrist is stretched, wrist is bent four action pattern state recognition algorithms, and do evil through another person according to the action pattern information-driven that obtains, reach the do evil through another person control of corresponding four actions of two degrees of freedom.Form one and have the bionical neural EMG-controlling prosthetic hand of two degrees of freedom that a kind of like this control approach of control motor was handled and controlled → do evil through another person to brain → nerve → forearm muscle → surface electromyogram signal → single-chip machine information.
In the work of two degrees of freedom EMG-controlling prosthetic hand, the power of three road SEMG and the corresponding relation of doing evil through another person between action pattern are as shown in table 1, and it has reflected a kind of determination methods, are exactly in fact aforementioned SCM Based four action pattern state recognitions.Open, close up, wrist is stretched, wrist is bent four action pattern state recognition algorithms and meant different strong, the weak combination by three road SEMG of extensor carpi ulnaris m., flexor carpi ulnaris m., extensor digitorum's correspondence, obtain doing evil through another person open, close up, wrist is stretched, wrist is bent four action pattern status informations.The corresponding relation such as the table 1 of the strong and weak combination of three road SEMG and four actions:
The strong and weak composite type of signal | Surface electromyogram signal (SEMG) | Recognition result |
Extensor carpi ulnaris m. | Flexor carpi ulnaris m. | Extensor digitorum |
1 | By force | A little less than | - | Stretch wrist |
2 | A little less than | By force | - | Bend wrist |
3 | By force | By force | - | Close up |
4 | A little less than | A little less than | By force | Open |
5 | A little less than | A little less than | A little less than | Attonity |
Table 1
Work process is described:
When the people with disability who wears the two degrees of freedom EMG-controlling prosthetic hand needs the artificial hand controlled action, because the phantom limb sense that the people with disability had, only need as being intended to control, healthy people finish corresponding action, EMG-controlling prosthetic hand will be according to three road SEMG of corresponding hand motion, on judgement, base of recognition, artificial hand controlled is finished corresponding action: turn over sports consciousness on the wrist, do evil through another person and finish wrist synchronously and stretch action; Turn over sports consciousness under the wrist, do evil through another person and finish wrist action in the wrong synchronously; The five fingers stretching consciousness, the hand of doing evil through another person opens; The sports consciousness of clenching fist, the hand of doing evil through another person closes up; Hand loosens consciousness, does evil through another person and does not do any action.Avoid the multi-freedom degree muscle-electric artificial hand of conventional commercial need be, realized the do evil through another person real-time control of four actions of two degrees of freedom by switching the situation just can reach the control of multiple freedom degrees hand-prosthesis.