A hybrid haptic stimulation system for providing feedback to an amputee on prosthetic wrist movement information

Abstract

The application discloses a hybrid tactile stimulation system for feeding back artificial limb wrist movement information for amputees, which realizes data interaction with a myoelectric artificial limb and provides real-time sensory feedback of wrist movement for the user. The myoelectric artificial limb comprises a receiving cavity, myoelectric collection electrodes and a wrist joint motor with an encoder. The hybrid tactile stimulation system comprises a myoelectric signal analog-digital conversion module, a motor driving module, a main control module, a tactile stimulation module and a multi-channel hybrid tactile stimulation electrode array module. The application compensates for the deficiency of vibration tactile in real-time through hybrid tactile stimulation, especially electric tactile, provides effective transition sensory information, and reduces the discomfort caused by electric stimulation. The innovative design not only enhances the possession and control ability of the user to the artificial limb, but also shortens the time for learning to control the artificial limb, improves the use efficiency of the artificial limb, improves the movement function of the amputees and improves the use rate of the artificial limb in daily life.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of haptic stimulation devices, and particularly relates to a hybrid haptic stimulation system for feeding back wrist movement information of a prosthetic limb to an amputee. BACKGROUND

[0002] Prostheses are an effective rehabilitation method for patients with limb disabilities. According to surveys, about 74% of people with limb disabilities are willing to consider using prostheses. However, the abandonment rates of myoelectric prosthetic hands in children and adults are 35% and 23% respectively, and one of the main reasons is the lack of somatosensory feedback.

[0003] Currently, some technologies have been improved to address the lack of sensory feedback in prostheses. Sensory substitution technology converts environmental information received by damaged senses into stimuli, which act on healthy senses, thereby delivering original environmental information to users. These technologies can be divided into two categories according to the interface with the nerve: invasive technology, such as directly stimulating nerves through implantable interfaces; and non-invasive technology, such as galvanic and vibrotactile haptics, which produce sensory feedback by activating different receptors on the skin.

[0004] Using haptic feedback to replace the movement sensation of amputees on prostheses is one of the current research methods for sensory feedback of prostheses. With the development of sensing, neural interface and other technologies, haptic feedback systems can achieve more accurate, natural and personalized tactile sensation transmission. It provides amputees with the ability to perceive the external environment and the position of the prosthesis, helping them to control the movement of the prosthesis more accurately, thereby enhancing their experience of using the prosthesis. Although current haptic feedback systems have made some progress, the human tactile system is very complex, and we still need more in-depth research to find more efficient feedback methods.

[0005] Current research on haptic feedback of prosthetic limb movement information for amputees still has the following problems:

[0006] 1) The singularity of haptic feedback information. Existing prosthetic haptic feedback systems usually rely on a single type of haptic stimulation (such as vibrotactile or galvanic haptic), which is insufficient in terms of feedback throughput. This single mode of feedback cannot fully transmit the diverse information required for prosthetic limb movement, limiting the accurate control of prosthetic limb movement.

[0007] 2) User adaptability and comfort. Although vibrotactile and galvanic haptic feedback are widely used in many prosthetic control systems, the response time of vibrotactile feedback is relatively long (sometimes up to 400 ms), which performs poorly in fast dynamic movement tasks. Continuous galvanic haptic feedback is difficult for many users to adapt to in the long term due to its "stinging" or "burning" sensation, which limits its widespread application.

[0008] 3) The correlation between tactile stimulation and control accuracy has not been systematically studied. Most existing research focuses on the subject's ability to perceive tactile stimulation, rather than in combination with fine motor control tasks for prostheses, which reduces the effectiveness of the prosthetic tactile feedback technology. Because the purpose of prosthetic sensory feedback is to improve motor control, the testing of prosthetic motor control tasks is an important part of the evaluation of prosthetic sensory feedback. Therefore, this limitation hinders the development of tactile technology for prosthetic motion information feedback. SUMMARY

[0009] The purpose of the present application is to provide a hybrid tactile stimulation system for feedback of prosthetic wrist motion information for amputees, which interacts with myoelectric prostheses to provide sensory feedback for the user's wrist.

[0010] The myoelectric prosthesis includes a receiving cavity, a myoelectric collection electrode, and a wrist joint motor with an encoder.

[0011] The hybrid tactile stimulation system includes a myoelectric signal analog-to-digital conversion module, a motor drive module, a main control module, a tactile stimulation module, and a multi-channel hybrid tactile stimulation electrode array module.

[0012] The multi-channel hybrid tactile stimulation electrode array module includes n miniature vibration motors, n electro-tactile stimulation electrodes, an FPC connector, and a flexible circuit board, where n is a positive integer.

[0013] The miniature vibration motor is used to generate vibration stimulation on the user's upper arm.

[0014] The electro-tactile stimulation electrode is attached to the user's upper arm of the myoelectric prosthesis to generate electro-tactile stimulation on the user's upper arm.

[0015] The FPC connector connects the n miniature vibration motors and the n electro-tactile stimulation electrodes to the tactile stimulation module through a wire, thereby achieving multi-channel output of hybrid tactile stimulation.

[0016] One surface of the flexible circuit board is spaced apart by n miniature vibration motors, and the other surface is spaced apart by n electro-tactile stimulation electrodes.

[0017] The myoelectric collection electrode acquires two-channel myoelectric signals from a pair of antagonistic muscles in the user's forearm.

[0018] The myoelectric signal analog-to-digital conversion module performs analog-to-digital conversion on the two-channel myoelectric signals to obtain corresponding digital signals, and generates a prosthetic motion control instruction based on the corresponding digital signals of the two-channel myoelectric signals.

[0019] The myoelectric signal analog-to-digital conversion module generates a motor drive signal and sends it to the main control module.

[0020] The main control module receives the motor driving signal, and controls the wrist joint motor with an encoder in the myoelectric prosthesis to move according to the prosthesis motion control instruction.

[0021] When the myoelectric prosthesis moves, the encoder of the wrist joint motor with an encoder feeds back the motor rotation angle to monitor the prosthesis motion posture information in real time, and transmits the prosthesis motion posture information to the main control module.

[0022] The main control module encodes the prosthesis motion posture information into a tactile stimulation pattern, and controls the tactile stimulation module to output a tactile stimulation sequence on the multi-channel hybrid tactile stimulation electrode array module.

[0023] Further, the system further comprises a power conversion isolation module.

[0024] The power conversion isolation module supplies power to the myoelectric collection electrode, the myoelectric signal analog-digital conversion module, the motor driving module, the wrist joint motor with an encoder, the main control module, the tactile stimulation module, and the multi-channel hybrid tactile stimulation electrode array module.

[0025] The power conversion isolation module isolates the power supply of the myoelectric collection electrode and the myoelectric signal analog-digital conversion module from the power supply of the motor driving module, the wrist joint motor with an encoder, the main control module, the tactile stimulation module, and the multi-channel hybrid tactile stimulation electrode array module.

[0026] Further, the prosthesis motion control instruction includes the steering and rotation speed of the myoelectric prosthesis wrist joint.

[0027] Further, the movement type of the myoelectric prosthesis includes wrist flexion and wrist extension.

[0028] Further, the positions of the micro-vibration motors on the flexible circuit board correspond to the positions of the electro-tactile stimulation electrodes.

[0029] Further, the voltage amplitude range received by the micro-vibration motor is [0, 3.3V].

[0030] Further, the stimulation intensity range of the electro-tactile stimulation electrode is [0, 8mA].

[0031] Further, the amplitude range of the tactile stimulation sequence output by the tactile stimulation module is [b, 3.3V], the modulation frequency range is [20Hz, 200Hz], the amplitude range of the electro-tactile stimulation sequence is [c, d], and the modulation frequency range is [0, 200Hz], wherein b is the vibration sensation threshold, c is the electro-tactile sensation threshold, and d is the electro-tactile pain threshold.

[0032] Further, the parameters of the vibration stimulation include vibration frequency, vibration duration, vibration intensity, and vibration interval duration.

[0033] Further, the stimulation waveform of the electrohaptic stimulation includes a double-phase rectangular pulse.

[0034] The parameters of the electrohaptic stimulation include a stimulation frequency, a stimulation amplitude, a stimulation pulse width, and a stimulation delay.

[0035] The technical effect of the present application is self-evident. The present application integrates an electrohaptic stimulation system and a vibration haptic stimulation system into one system, which can output stimulation signals of two modalities in parallel. The system can not only match more types of actions of a prosthetic hand and information, but also can fully amplify the advantages of the two modalities in information transmission and avoid their disadvantages. For example, an electrohaptic stimulation signal is used to transmit information about the movement process of a prosthetic hand (to avoid the problem of long response time of vibration haptic stimulation in fast dynamic movement), and a vibration haptic stimulation signal is used to transmit position information of the prosthetic hand (to avoid the discomfort caused by long duration of continuous electrohaptic stimulation).

[0036] The present application uses a mixed modality haptic substitution feedback method, which effectively improves the comfort and accuracy of induced sensation by reasonably allocating the feedback strategies of vibration haptic and electrohaptic stimulation. At the same time, the present application adopts a compact structure design, places a vibration motor on the back of a stimulation electrode, increases the stimulation modalities without increasing the area of the stimulation interface, and uses a high-precision flexible stimulation electrode array instead of commonly used disposable hydrogel stimulation electrodes, which increases the number of uses of the electrodes and reduces the area of the electrodes, thereby increasing the accuracy and resolution of the stimulation, and has good adaptability and stability.

[0037] The present application provides a small and portable multifunctional prosthetic mixed haptic stimulation-control system. When a person with amputation performs rehabilitation training and prosthetic fitting, the real-time movement information of the prosthetic joint is detected and converted into haptic stimulation to induce the subject to produce various sensations, so that the subject can immediately adjust the myoelectric signal of the residual limb to improve the fine motor control effect of the prosthetic hand, thereby enhancing the subject's sense of possession of the prosthetic hand, saving the user's time to learn to control the prosthetic hand, enhancing the subject's motor function, and improving the prosthetic usage rate in daily life.

[0038] The mixed haptic stimulation-control system provided by the present application is a supplement to the original myoelectric prosthetic function, which is combined with the control function of the myoelectric prosthetic in function to form a closed loop of control-sensation-control, and the whole system is packaged in a compact myoelectric prosthetic device.

[0039] The mixed haptic stimulation-control system provided by the present application is embedded in the receiving cavity of the myoelectric prosthetic in structure, which is convenient to carry and wear. In addition, low-power components and circuit design are used to improve the use time of the system and provide better user experience.

[0040] The application can be applied in the fields of virtual reality, medical rehabilitation, human-computer interaction and the like. BRIEF DESCRIPTION OF DRAWINGS

[0041] Figure 1 A working schematic diagram of the mixed tactile stimulation system according to the application;

[0042] Figure 2 A module schematic diagram of the entire system according to the application;

[0043] Figure 3 A mixed tactile stimulation array module schematic diagram according to the application and distributed on two surfaces of a flexible circuit board; Figure 3 (a) is a schematic diagram of one surface of the flexible circuit board on which a micro-vibration motor array is placed; Figure 3 (b) is a schematic diagram of one surface of the flexible circuit board on which an electro-tactile stimulation electrode array is placed;

[0044] Figure 4 Selection of the micro-vibration motor used in the application;

[0045] Figure 5 A mapping relationship schematic diagram of the sensory substitution method used in the application, Figure 5 (a) is an example diagram of the position of the prosthesis corresponding to the stimulation position when the prosthesis wrist performs flexion and extension action; Figure 5 (b) is an example diagram of the target position of the prosthesis corresponding to the movement state;

[0046] Figure 6 A mixed tactile stimulation strategy schematic diagram used in the application;

[0047] In the figure, the myoelectricity collection electrode 1, the myoelectricity signal analog-digital conversion module 2, the motor driving module 3, the wrist joint motor with an encoder 4, the main control module 5, the tactile stimulation module 6, the multi-channel mixed tactile stimulation electrode array module 7, the prosthesis movement posture information 8, the micro-vibration motor 9, the FPC connector 10. DETAILED DESCRIPTION

[0048] The application will be further described below in conjunction with the embodiments, but should not be understood as limiting the above-mentioned subject matter of the application to the following embodiments. According to the ordinary technical knowledge and conventional means in the art, various substitutions and changes can be made without departing from the above-mentioned technical idea of the application, and all should be included in the protection scope of the application.

[0049] Example 1:

[0050] Referring to Figures 1 to 6 A mixed tactile stimulation system for feeding back the movement information of the prosthesis wrist of an amputee, the mixed tactile stimulation system performing data interaction with the myoelectricity prosthesis and providing the user with the sensory feedback of the wrist.

[0051] The myoelectric artificial limb comprises a receiving cavity, a myoelectric collection electrode 1, and a wrist joint motor 4 with an encoder.

[0052] The hybrid tactile stimulation system comprises a myoelectric signal analog-digital conversion module 2, a motor driving module 3, a main control module 5, a tactile stimulation module 6, and a multi-channel hybrid tactile stimulation electrode array module 7.

[0053] The multi-channel hybrid tactile stimulation electrode array module 7 comprises n micro-vibration motors 9, n electro-tactile stimulation electrodes, an FPC connector 10, and a flexible circuit board, where n is a positive integer.

[0054] The micro-vibration motor 9 is used to generate vibration stimulation on the user's upper arm.

[0055] The electro-tactile stimulation electrode is attached to the user's upper arm of the myoelectric artificial limb, and is used to generate electro-tactile stimulation on the user's upper arm.

[0056] The FPC connector 10 connects the n micro-vibration motors and the n electro-tactile stimulation electrodes with the tactile stimulation module 6 through a wire, so as to realize multi-channel output of hybrid tactile stimulation.

[0057] One surface of the flexible circuit board is spaced apart from the n micro-vibration motors 9, and the other surface is spaced apart from the n electro-tactile stimulation electrodes.

[0058] The myoelectric collection electrode 1 acquires two-channel myoelectric signals of a pair of antagonistic muscles of the user's forearm.

[0059] The myoelectric signal analog-digital conversion module 2 performs analog-digital conversion on the two-channel myoelectric signals to obtain corresponding digital signals, and generates an artificial limb motion control instruction based on the corresponding digital signals of the two-channel myoelectric signals.

[0060] The myoelectric signal analog-digital conversion module 2 generates a motor driving signal and sends the motor driving signal to the main control module 5.

[0061] After receiving the motor driving signal, the main control module 5 controls the motor driving module 3 to control the wrist joint motor 4 with an encoder in the myoelectric artificial limb to act according to the artificial limb motion control instruction.

[0062] When the myoelectric artificial limb moves, the encoder of the wrist joint motor 4 with an encoder feeds back the motor rotation angle to monitor the artificial limb motion posture information 8 in real time, and transmits the artificial limb motion posture information 8 to the main control module 5.

[0063] The main control module 5 encodes the artificial limb motion posture information 8 into a tactile stimulation mode, and controls the tactile stimulation module 6 to output a tactile stimulation sequence on the multi-channel hybrid tactile stimulation electrode array module 7.

[0064] Embodiment 2:

[0065] A hybrid tactile stimulation system for amputees to feedback prosthesis wrist movement information, the main technical content is seen in embodiment 1, further, the system further comprises a power conversion isolation module.

[0066] The power conversion isolation module supplies power for the myoelectric collection electrode 1, the myoelectric signal analog-digital conversion module 2, the motor driving module 3, the wrist joint motor with encoder 4, the main control module 5, the tactile stimulation module 6, and the multi-channel hybrid tactile stimulation electrode array module 7.

[0067] The power conversion isolation module isolates the power supply of the myoelectric collection electrode 1 and the myoelectric signal analog-digital conversion module 2 from the power supply of the motor driving module 3, the wrist joint motor with encoder 4, the main control module 5, the tactile stimulation module 6, and the multi-channel hybrid tactile stimulation electrode array module 7.

[0068] Embodiment 3:

[0069] A hybrid tactile stimulation system for amputees to feedback prosthesis wrist movement information, the main technical content is seen in any one of embodiments 1 to 2, further, the prosthesis movement control instruction includes the steering and rotation speed of the myoelectric prosthesis wrist joint.

[0070] Embodiment 4:

[0071] A hybrid tactile stimulation system for amputees to feedback prosthesis wrist movement information, the main technical content is seen in any one of embodiments 1 to 3, further, the movement type of the myoelectric prosthesis includes wrist flexion and wrist extension.

[0072] Embodiment 5:

[0073] A hybrid tactile stimulation system for amputees to feedback prosthesis wrist movement information, the main technical content is seen in any one of embodiments 1 to 4, further, the position of the micro-vibration motor 9 on the flexible circuit board corresponds to the position of the electro-tactile stimulation electrode.

[0074] Embodiment 6:

[0075] A hybrid tactile stimulation system for amputees to feedback prosthesis wrist movement information, the main technical content is seen in any one of embodiments 1 to 5, further, the voltage amplitude range received by the micro-vibration motor 9 is [0, 3.3V].

[0076] Embodiment 7:

[0077] A hybrid tactile stimulation system for amputees to feedback prosthesis wrist movement information, the main technical content is seen in any one of embodiments 1 to 6, further, the electro-tactile stimulation electrode stimulation intensity range is [0, 8mA].

[0078] Embodiment 8:

[0079] A hybrid tactile stimulation system for feedback of prosthetic wrist movement information to amputees, the main technical content is seen in any one of embodiments 1 to 7, further, the amplitude range of the tactile stimulation sequence output by the tactile stimulation module 6 is [b, 3.3V], the modulation frequency range is [20Hz, 200Hz], the amplitude range of the electro-tactile stimulation sequence is [c, d], the modulation frequency range is [0, 200Hz], wherein b is the vibration sensation threshold, c is the electro-tactile sensation threshold, and d is the electro-tactile pain threshold.

[0080] Embodiment 9:

[0081] A hybrid tactile stimulation system for feedback of prosthetic wrist movement information to amputees, the main technical content is seen in any one of embodiments 1 to 8, further, the parameters of the vibration stimulation include vibration frequency, vibration duration, vibration intensity, and vibration interval duration.

[0082] Embodiment 10:

[0083] A hybrid tactile stimulation system for feedback of prosthetic wrist movement information to amputees, the main technical content is seen in any one of embodiments 1 to 9, further, the stimulation waveform of the electro-tactile stimulation includes a biphasic rectangular pulse.

[0084] The parameters of the electro-tactile stimulation include stimulation frequency, stimulation amplitude, stimulation pulse width, and stimulation delay.

[0085] Embodiment 11:

[0086] Referring to Figures 1 to 6 A hybrid tactile stimulation system for feedback of prosthetic wrist movement information to amputees, the hybrid tactile stimulation system interacts with the myoelectric prosthesis to provide sensory feedback to the user's wrist.

[0087] The myoelectric prosthesis includes a receiving cavity, a myoelectric collection electrode 1, and a wrist joint motor 4 with an encoder.

[0088] The hybrid tactile stimulation system includes a myoelectric signal analog-to-digital conversion module 2, a motor drive module 3, a main control module 5, a tactile stimulation module 6, and a multi-channel hybrid tactile stimulation electrode array module 7.

[0089] The multi-channel hybrid tactile stimulation electrode array module 7 includes n micro-vibration motors 9, n electro-tactile stimulation electrodes, an FPC connector 10, and a flexible circuit board, where n is a positive integer.

[0090] The micro-vibration motor 9 is used to generate vibration stimulation on the user's upper arm.

[0091] The micro-vibration motor is selected from a rotor motor with a diameter of 10 mm, a thickness of 2.7 mm, a rated rotating speed of 11000±2500 rpm, a rated operating voltage of 3.0 V, and a rated current of 80 mA.

[0092] The micro-vibration motor is driven by a PWM square wave, and a user can change the duty cycle of the PWM applied to the motor, thereby changing the effective voltage across the motor, and ultimately changing the vibration intensity of the motor. Each motor can achieve independent parameter control.

[0093] The electrohaptic stimulation electrode is attached to the upper arm of the myoelectric prosthesis user, and is used to generate electrohaptic stimulation on the user's upper arm.

[0094] The electrohaptic stimulation is output by the thin film electrode in combination with the hydrogel, and the stimulation waveform is a biphasic rectangular pulse, and the parameters include stimulation frequency, stimulation amplitude, stimulation pulse width, and stimulation delay.

[0095] The FPC connector 10 connects the n micro-vibration motors and the n electrohaptic stimulation electrodes to the haptic stimulation module 6 through the flat cable, thereby realizing multi-channel output of mixed haptic stimulation.

[0096] One surface of the flexible circuit board is spaced apart from the n micro-vibration motors 9, and the other surface is spaced apart from the n electrohaptic stimulation electrodes.

[0097] The multi-channel mixed haptic stimulation electrode array module 7 is a 2-layer flexible circuit board made of a material with good bending property, with a board thickness of 0.12 mm±0.03 mm, a yellow cover film, and a copper surface, which can be closely attached to the user's skin.

[0098] The size of the flexible circuit board meets the arm circumference length range of the upper limbs of adult human body, and the single size is 112.5 mm*73 mm.

[0099] As shown in Figure 3 The flexible stimulation electrode array is mainly composed of a micro-vibration motor 9, an electrohaptic stimulation electrode, an FPC connector 10, and a flexible circuit board, and is composed of a silicon substrate, a thin film electrode, and a micro-vibration motor, which has the advantages of simple structure, stable output signal, and accurate frequency response. Each stimulation electrode is spaced apart by 26 mm, which meets the two-point threshold that can be perceived by the human body.

[0100] The myoelectric collection electrode 1 acquires two-channel myoelectric signals of a pair of antagonistic muscles of the user's forearm.

[0101] The myoelectric signal analog-digital conversion module 2 performs analog-digital conversion on the two-channel myoelectric signals to obtain corresponding digital signals, and generates a prosthesis movement control instruction based on the corresponding digital signals of the two-channel myoelectric signals.

[0102] The generation of the prosthesis motion control instruction is as follows: comparing the amplitudes of the two channel signals, if the amplitude of channel A is higher than that of channel B by a certain threshold, a positive rotation instruction of the motor is generated, otherwise a reverse rotation instruction of the motor is generated, and the specific threshold is adjusted according to the intensity of the user's electromyographic signal.

[0103] The electromyographic signal analog-digital conversion module 2 generates a motor driving signal and sends the motor driving signal to the main control module 5.

[0104] The electromyographic signal analog-digital conversion module 2 judges the amplitude difference of the two channel electromyographic signals, generates a prosthesis motion control instruction, and sends a motor driving signal to the main control module 5.

[0105] The electromyographic signal analog-digital conversion module 2 uses an STM32F103RCT6 chip, which has multiple peripherals built-in, including an analog-digital converter, a timer, an interrupt controller, a digital interface integrated circuit, and various communication interfaces, which can help users achieve more flexible and complex functions. It is an embedded system with high performance, low cost, low power consumption, etc., which can provide control signals for the design.

[0106] After receiving the motor driving signal, the main control module 5 makes the motor driving module 3 control the wrist joint motor 4 with an encoder in the electromyographic prosthesis to act according to the prosthesis motion control instruction.

[0107] The motor driving module 3 is realized by a direct current motor driving chip L293B, which contains four independent drivers, and the motor supply voltage can reach up to 36V, which can provide an output current of 1A. In this design, in order to realize the forward and reverse rotation of the motor, drivers 1 and 2 are combined into a group of driving hands. The logic part of this module is powered by 5V, and the logic input can be provided by the IO pin 3.3V of the single-chip microcomputer. The opening time of the module is 750ns, and the closing time is 200ns, which fully meets the PWM control of the motor.

[0108] When the electromyographic prosthesis moves, the encoder of the wrist joint motor 4 with an encoder feeds back the motor rotation angle to monitor the prosthesis motion posture information 8 in real time, and transmits the prosthesis motion posture information 8 to the main control module 5.

[0109] The main control module 5 encodes the prosthesis motion posture information 8 into a tactile stimulation pattern, controls the tactile stimulation module 6 to output a tactile stimulation sequence on the multi-channel mixed tactile stimulation electrode array module 7.

[0110] The vibration stimulation part realizes the gating of the vibration channel through the 74LVC1G157GW multiplexer chip. When a high level is provided to the Select end of the chip, the PWM signal of the Input end is output to the Y end, thereby reaching the gate of the AO3400. Therefore, during the high level of the PWM wave, the 3.3V voltage of the drain is provided to the vibration motor connected to the source, thereby realizing the function of controlling the motor output stimulation.

[0111] The working process of the mixed tactile stimulation and motor control system is as follows:

[0112] 1) The multi-channel flexible stimulation electrode array is placed on the upper arm of the user, and the user wears the myoelectric prosthesis.

[0113] 2) The myoelectric acquisition electrodes are placed at the positions of a pair of antagonistic muscles on the forearm of the user. The flexion and extension movements of the wrist of the myoelectric prosthesis are realized through the amplitude of the myoelectric signals of the two muscles.

[0114] 3) The encoder reads the motor rotation angle information in real time to monitor the posture information of the prosthesis in real time, and transmits the information to the main control module.

[0115] 4) The main control module controls the tactile stimulation module through a specific communication method, selects the stimulation output channel, and sets the stimulation parameters. The vibration stimulation parameters include vibration frequency, vibration time, vibration intensity, and vibration interval time. The stimulation waveform of the electro-tactile stimulation is a double-phase rectangular pulse, and the parameters include stimulation frequency, stimulation amplitude, stimulation pulse width, and stimulation delay.

[0116] 5) After receiving the output signal, the multi-channel flexible vibration stimulation electrode array generates a specific mixed tactile stimulation acting on the upper arm of the user of the prosthesis.

[0117] 6) After the user's upper limb feels the tactile stimulation, the user performs the corresponding action or records the corresponding action of the current stimulation. The main control module detects the motor rotation state in real time and adjusts the stimulation parameters according to the motor rotation state, returns to step 4), and continues until the current action is completed.

[0118] Embodiment 12:

[0119] A mixed tactile stimulation system for feeding back the wrist movement information of the prosthesis of an amputee, the main technical content of which is shown in Embodiment 11. Further, the system further comprises a power conversion isolation module.

[0120] The power conversion isolation module supplies power for the myoelectric acquisition electrode 1, the myoelectric signal analog-digital conversion module 2, the motor driving module 3, the wrist joint motor 4 with an encoder, the main control module 5, the tactile stimulation module 6, and the multi-channel mixed tactile stimulation electrode array module 7.

[0121] The power conversion isolation module is a module that provides power support, uses the 8V rechargeable battery provided by the prosthesis, and obtains the corresponding voltage for power supply through the designed voltage conversion module: the power supply voltage of the myoelectric signal analog-digital conversion module, the main control module and the Bluetooth communication module is 3.3V, the power supply voltage of the myoelectric collection electrode and the driving module is 5V, and the vibration motor is selected to be powered by 3.3V voltage within the rated working voltage range. The size of the electro-tactile stimulation is controlled by a constant current source. Since the impedance of the human body is floating, in order to ensure that the current size within the preset range can be provided, a voltage of 70V needs to be provided. Therefore, the system designs multiple voltage conversion circuits, which are 8V to 12V, 12V to 70V, 12V to 5V and 5V to 3.3V.

[0122] The chip used in the 8V to 12V circuit is TPS61089RNRR, and the maximum output current of 7A can meet the power supply requirements of the system.

[0123] The 12V to 70V circuit adopts the DCDC switching power supply mode, and the circuit topology is a Boost circuit with feedback. The voltage level of this circuit is relatively high, and the system uses MCP1650S chip. The chip can lift the voltage to more than 100V, and the allowed output is 5W, and the working static current is 120μA, which meets the design needs.

[0124] The 12V to 5V uses a high-performance Buck-type DCDC chip TPS563201 produced by Texas Instruments. The input voltage range of this chip is 2.95V to 17V, and the output voltage can be adjusted according to the external circuit, usually between 0.8V and 6V. In this circuit, two sets of resistance values connected to the VFB interface are set to set the output voltage to 5V, and the maximum output current can reach 3A.

[0125] The chip used in the 5V to 3.3V circuit is TLV70433, which is a low-dropout linear regulator chip with low-dropout and low quiescent current characteristics. It can be used to convert input voltage from 3.5V to 28V to output voltage from 1.2V to 5.5V. The circuit using TLV70433 is very simple and easy to design, which can reduce the number of components and cost in the system.

[0126] The power conversion isolation module isolates the power supply of the myoelectric collection electrode 1, the myoelectric signal analog-digital conversion module 2, the motor driving module 3, the wrist joint motor with encoder 4, the main control module 5, the tactile stimulation module 6, and the multi-channel mixed tactile stimulation electrode array module 7.

[0127] The power isolation function is realized by the isolation module URB2412YMD-10WR3, which realizes 12V-12V DCDC isolation, and the output power can reach 10W. The power supply and the subsequent application circuit part are separated by using the power isolation module, the isolation voltage is as high as 1500VDC, and the system safety is improved.

[0128] The myoelectric artificial limb further comprises a rechargeable battery.

[0129] The battery voltage is 8V, which is rechargeable and is the power supply of the whole system.

[0130] Embodiment 13:

[0131] A hybrid tactile stimulation system for feeding back artificial limb wrist movement information to amputees, the main technical content of which is seen in any one of embodiments 11 to 12, further, the artificial limb movement control instruction comprises the steering and rotating speed of the myoelectric artificial limb wrist joint.

[0132] The motor drive module is realized by a DC motor drive chip L293B, which contains 4 independent drivers, and the motor supply voltage can be as high as 36V, which can provide an output current of 1A. In this design, in order to realize the forward and reverse rotation of the motor, drivers 1 and 2 are combined into a group of driving hands. The logic part of the module is powered by 5V, and the logic input can be provided by the IO pin 3.3V of the single-chip microcomputer. The opening time of the module is 750ns, and the closing time is 200ns, which fully meets the PWM control of the motor.

[0133] Embodiment 14:

[0134] A hybrid tactile stimulation system for feeding back artificial limb wrist movement information to amputees, the main technical content of which is seen in any one of embodiments 11 to 13, further, the movement type of the myoelectric artificial limb includes wrist flexion and wrist extension, and the angle range is 0° to 60°.

[0135] Embodiment 15:

[0136] A hybrid tactile stimulation system for feeding back artificial limb wrist movement information to amputees, the main technical content of which is seen in any one of embodiments 11 to 14, further, the position of the micro-vibration motor 9 on the flexible circuit board corresponds to the position of the electro-tactile stimulation electrode.

[0137] The surface of the flexible circuit board is plated with a layer of copper film.

[0138] The multi-channel hybrid tactile stimulation electrode array module 7 is a 2-layer flexible circuit board made of a material with good bending property, which can closely adhere to the user's skin.

[0139] The thickness of the flexible circuit board is 0.12mm, and the surface is plated with a layer of copper film, a yellow covering film, and the surface is made of copper material.

[0140] The size of the flexible circuit board conforms to the arm circumference length range of the upper limbs of adult human body, and a single size is 112.5mm*73mm.

[0141] Embodiment 16:

[0142] A hybrid tactile stimulation system for amputees to feedback prosthesis wrist movement information, the main technical content is seen in any one of embodiments 11 to 15, further, the voltage amplitude range received by the micro-vibration motor 9 is [0, 3.3V].

[0143] Embodiment 17:

[0144] A hybrid tactile stimulation system for amputees to feedback prosthesis wrist movement information, the main technical content is seen in any one of embodiments 11 to 16, further, the stimulation intensity range of the electro-tactile stimulation electrode is [0, 8mA].

[0145] Embodiment 18:

[0146] A hybrid tactile stimulation system for amputees to feedback prosthesis wrist movement information, the main technical content is seen in any one of embodiments 11 to 17, further, the amplitude range of the tactile stimulation sequence output by the tactile stimulation module 6 is [b, 3.3V], the modulation frequency range is [20Hz, 200Hz], the amplitude range of the electro-tactile stimulation sequence is [c, d], the modulation frequency range is [0, 200Hz], wherein b is the vibration sensation threshold, c is the electro-tactile sensation threshold, and d is the electro-tactile pain threshold.

[0147] The measurement method of the vibration sensation threshold is to increase the vibration amplitude by a certain gradient from 0 until the subject starts to report feeling the stimulation, and the amplitude at this time is recorded as the sensation threshold.

[0148] The measurement method of the electro-tactile sensation threshold is to increase the electric stimulation amplitude by a certain gradient from 0 until the subject starts to report feeling the stimulation, and the amplitude at this time is recorded as the sensation threshold. Continue to increase the electric stimulation amplitude until the subject starts to report discomfort, and the amplitude at this time is recorded as the pain threshold.

[0149] Embodiment 19:

[0150] A hybrid tactile stimulation system for amputees to feedback prosthesis wrist movement information, the main technical content is seen in any one of embodiments 11 to 18, further, the parameters of the vibration stimulation include vibration frequency, vibration duration, vibration intensity, and vibration interval duration.

[0151] Embodiment 20:

[0152] A hybrid tactile stimulation system for feedback of prosthetic wrist movement information to amputees, the main technical content is seen in any one of embodiments 11 to 19, further, the stimulation waveform of the electro-tactile stimulation includes a biphasic rectangular pulse.

[0153] The parameters of the electro-tactile stimulation include stimulation frequency, stimulation amplitude, stimulation pulse width, and stimulation delay.

[0154] Embodiment 21:

[0155] A hybrid tactile stimulation system for feedback of prosthetic wrist movement information to amputees, the main technical content is seen in any one of embodiments 11 to 20, further, the system is embedded in a myoelectric prosthesis and electrically connected to the myoelectric prosthesis, and provides different modes of hybrid tactile stimulation according to the kinematic parameters of the prosthesis, helping the user to obtain sensory feedback while manipulating the prosthesis.

[0156] When the 4 positions of wrist flexion and extension are mapped to the electro-tactile stimulation induced by different channels of the hybrid tactile electrode array, the static position sensation and dynamic isokinetic movement sensation are established according to the timing established by the stimulation position.

[0157] The flexible hybrid tactile electrode array includes 4 micro-vibration motors and 4 electro-tactile stimulation electrodes, which are respectively denoted as vibration channels: VCH1, VCH2, VCH3, VCH4, and electro-stimulation channels: ECH1, ECH2, ECH3, ECH4. The vibration and electro-stimulation of the same channel number are at the same position of the electrode array. The two electrodes on the dorsal side of the upper arm correspond to the wrist extension direction of the prosthetic wrist, while the two electrodes on the palmar side correspond to the wrist flexion direction. The greater the angle of movement, the more distant the activated stimulation channel is from the central axis.

[0158] The movement posture information of the myoelectric prosthesis is mapped to different modes of tactile stimulation. When the myoelectric prosthesis movement posture information position is E30, the stimulation channels are VCH1 and ECH1, when the position is E15, the stimulation channels are VCH2 and ECH2, when the position is F15, the stimulation channels are VCH3 and ECH3, and when the position is F30, the stimulation channels are VCH4 and ECH4. E and F represent wrist extension and wrist flexion respectively, and 15 and 30 represent movement angles of 15° and 30° respectively. The stimulation channel changes with the change of the prosthesis angle.

[0159] In the mapping mode of the hybrid tactile stimulation channel and the isokinetic movement information of the prosthesis, the electro-tactile stimulation frequency of each channel is fixed, ranging between [0, 200Hz], and the stimulation intensity is fixed, ranging between [0, 8mA]. The vibration stimulation duration is 2 seconds, and the stimulation frequency and intensity are fixed. When the prosthesis stays at the target position, the electro-tactile stimulation will last for 0.5 seconds and then turn off, while the vibration tactile stimulation will last for 2 seconds and then turn off.

[0160] The design of this hybrid haptic feedback mode can utilize the real-time nature of electrohaptics to provide immediate position information to the subject, especially during the process of prosthetic movement. For example, during the process of wrist flexion from E30 to F30, the real-time response of electrohaptics can allow the subject to perceive the passing of key positions such as E15 and F15, thereby avoiding missing the feedback of intermediate positions due to the long response time of vibrotactile and reducing the confusion of position perception.

[0161] When the prosthetic stays at the target position, the electrohaptics is turned off after 500 ms, which can effectively reduce the discomfort and interference with the electromyographic signal caused by long-term electrical stimulation. Then, the vibrotactiles continue to provide position confirmation information, which not only avoids the disadvantage of poor real-time performance of vibrotactiles, but also fully utilizes the advantages of vibrotactiles in comfort and small interference with electromyographic signals.

[0162] Embodiment 22:

[0163] A hybrid haptic stimulation system for providing wrist movement information of a prosthetic to an amputee, the main technical content of which is seen in any one of embodiments 11 to 21, further, a wrist joint proprioception reconstruction method based on sensory substitution, the content of which is as follows:

[0164] This method realizes the reconstruction of the angle and speed of wrist flexion and extension in different ways; the four positions of wrist flexion and extension are mapped to the haptics induced by different channels of electrohaptic electrodes, and on this basis, the isokinetic movement sensation is established; three speeds of wrist flexion and extension are mapped to the haptics induced by different frequencies of vibration electrodes, and on this basis, the variable speed movement sensation is established.

[0165] When the electromyographic prosthetic movement posture information position is ST, it belongs to the initial position without stimulation, the position is E30, the electrohaptic channel 1 is stimulated, the position is E15, the electrohaptic channel 2 is stimulated, the position is F15, the electrohaptic channel 3 is stimulated, and the position is F30, the electrohaptic channel 4 is stimulated. E and F represent wrist extension and wrist flexion respectively, and 15 and 30 represent movement angles of 15° and 30° respectively. The stimulated channel changes with the change of the angle of the prosthetic;

[0166] When the electromyographic prosthetic movement posture information is wrist flexion, the electrohaptic stimulation is sequentially performed in the channel in a clockwise direction, and the greater the angle, the farther the stimulated channel is from the central axis; the vibrotactile stimulation simultaneously activates channel 3 and channel 4.

[0167] When the electromyographic prosthetic movement posture information is wrist extension, the electrohaptic stimulation is sequentially performed in the channel in an anticlockwise direction, and the greater the angle, the farther the stimulated channel is from the central axis; the vibrotactile stimulation simultaneously activates channel 1 and channel 2.

[0168] When the myoelectric prosthesis motion posture information is high speed, the vibration stimulation is correspondingly set to high frequency, when the myoelectric prosthesis motion posture information is medium speed, the vibration stimulation is correspondingly set to medium frequency, and when the myoelectric prosthesis motion posture information is low speed, the vibration stimulation is correspondingly set to low frequency.

[0169] Embodiment 23:

[0170] Referring to Figures 1 to 6 A hybrid tactile stimulation system for feeding the wrist motion information of a prosthesis to an amputee, the system comprising a master control module, a motor drive module, a tactile stimulation module, a hybrid tactile stimulation electrode array module, embedded in a myoelectric prosthesis to provide sensory feedback to the user.

[0171] The myoelectric prosthesis comprises a receiving cavity, an encoder-equipped wrist joint motor, a myoelectric signal analog-to-digital conversion module, a myoelectric collection electrode, and a rechargeable battery.

[0172] The myoelectric signal analog-to-digital conversion module is electrically connected to the motor drive module to set the drive motor to forward or reverse rotation, adjust the rotation speed, etc., to control the corresponding motion of the prosthesis.

[0173] The master control module is electrically connected to the tactile stimulation module, selects the tactile stimulation channel according to the motor operating state and sets the stimulation parameters, and generates hybrid tactile stimulation acting on the upper arm of the prosthesis user.

[0174] The master control module controls n vibration output channels and n electro-tactile stimulation output channels of the stimulator, and each vibration output channel is connected to a vibration motor.

[0175] The vibration electrode array comprises n micro vibration motors fixed at predetermined positions on a flexible printed board at certain intervals, and the back surface is an electro-tactile stimulation electrode.

[0176] The tactile stimulation array is electrically connected to the tactile stimulator through a wire and an FPC connector, and is in close contact with the user's upper arm, outputting hybrid tactile stimulation.

[0177] The hybrid tactile stimulation-control system comprises the following components: a master control module, a motor drive module, a tactile stimulation module, a hybrid tactile stimulation electrode array module, and a power conversion isolation module, having the advantages of miniaturization and portability.

[0178] The working process of the tactile stimulation and motor control system is as follows:

[0179] 1) Place a multi-channel flexible stimulation electrode array on the user's upper arm, and wear the myoelectric prosthesis on the limb;

[0180] 2) The electromyography acquisition electrode is placed in the position of a pair of antagonistic muscles of the forearm of the user, and the flexion and extension movement of the wrist of the electromyography prosthesis is realized through the amplitude of the electromyography signals of the two muscles.

[0181] 3) The encoder reads the motor rotation angle information in real time to monitor the motion posture information of the prosthesis, and transmits the information to the master control module.

[0182] 4) The master control module controls the tactile stimulation module through a specific communication method, selects a stimulation output channel and sets stimulation parameters; the vibration stimulation parameters include vibration frequency, vibration duration, vibration intensity, and vibration interval duration; the stimulation waveform of the electro-tactile stimulation is a double-phase rectangular pulse, and the parameters include stimulation frequency, stimulation amplitude, stimulation pulse width, and stimulation delay.

[0183] 5) After receiving the output signal, the multi-channel flexible vibration stimulation electrode array generates a specific mixed tactile stimulation acting on the upper arm of the prosthesis user.

[0184] 6) After the user's upper limb feels the tactile stimulation, the corresponding action is performed or the corresponding action at the moment is recorded, the master control module detects the motor rotation state in real time and adjusts the stimulation parameters according to the motor rotation state, and returns to step 4) until the current action is completed.

[0185] The wrist motion posture type of the prosthesis includes wrist flexion and wrist extension, and the angle range is 0° to 60°.

[0186] The multi-channel mixed tactile stimulation electrode array module 7 is a 2-layer flexible circuit board made of a material with good bending property, which can closely adhere to the user's skin.

[0187] The flexible circuit board has a thickness of 0.12mm, and a surface plated with a layer of copper film, a yellow covering film, and a copper material on the surface.

[0188] The size of the flexible circuit board meets the arm circumference length range of adult upper limbs, and the single size is 112.5mm*73mm.

[0189] The system uses an 8V rechargeable battery for power supply, and the battery is embedded in the prosthesis receiving cavity. The stimulation intensity range of the micro-vibration motor is [0, 3.3V].

[0190] The amplitude range of the vibration stimulator output is [sensation threshold, 3.3V], and the modulation frequency range is [20, 200Hz]. The amplitude range of the electro-tactile stimulation sequence is [sensation threshold, pain threshold], and the modulation frequency range is [0, 200Hz].

[0191] A wrist joint proprioception reconstruction method based on sensory substitution:

[0192] The wrist proprioception reconstruction method based on the sense substitution is characterized in that: the wrist flexion and extension angle and speed are reconstructed through different ways; four positions of the wrist flexion and extension are mapped as the tactile sensation induced by the different channels of the electrohaptic electrode, and the isokinetic movement sensation is established on this basis; three speeds of the wrist flexion and extension are mapped as the tactile sensation induced by the different frequencies of the vibration electrode, and the variable speed movement sensation is established on this basis.

[0193] When the myoelectric prosthesis prosthesis movement posture information position is ST, it belongs to the initial position without stimulation, the position is E30, the electrohaptic channel 1 is stimulated, the position is E15, the electrohaptic channel 2 is stimulated, the position is F15, the electrohaptic channel 3 is stimulated, and the position is F30, the electrohaptic channel 4 is stimulated. E and F respectively represent wrist extension and wrist flexion, and 15 and 30 respectively represent movement angles of 15° and 30°. The stimulated channel changes with the change of the prosthesis angle;

[0194] When the myoelectric prosthesis prosthesis movement posture information is wrist flexion, the electrohaptic stimulation is sequentially performed in the channel in a clockwise direction, and the greater the angle, the farther the stimulated channel from the central axis; the vibration tactile stimulation simultaneously activates the channel 3 and the channel 4.

[0195] When the myoelectric prosthesis prosthesis movement posture information is wrist extension, the electrohaptic stimulation is sequentially performed in the channel in an anticlockwise direction, and the greater the angle, the farther the stimulated channel from the central axis; the vibration tactile stimulation simultaneously activates the channel 1 and the channel 2.

[0196] When the myoelectric prosthesis prosthesis movement posture information is high speed, the vibration stimulation is correspondingly set to high frequency, when the myoelectric prosthesis prosthesis movement posture information is medium speed, the vibration stimulation is correspondingly set to medium frequency, and when the myoelectric prosthesis prosthesis movement posture information is low speed, the vibration stimulation is correspondingly set to low frequency.

[0197] Embodiment 24:

[0198] Referring to Figures 1 to 6 A hybrid tactile stimulation system for feeding the wrist movement information of a prosthesis to an amputee, the system comprising a main control module, a motor drive module, a tactile stimulation module, a hybrid tactile stimulation electrode array module, embedded in a myoelectric prosthesis to provide sensory feedback to the user.

[0199] The hybrid tactile stimulation system is embedded in the internal receiving cavity of the myoelectric prosthesis during use, and the stimulation output part is closely connected with the user's arm, which is the core component of generating tactile stimulation.

[0200] The main control module uses STM32F103RCT6 as the main control chip, which is an embedded system with high performance, low cost, low power consumption and other advantages, and can provide control signals for the design.

[0201] The vibration stimulation part in the mixed tactile stimulation module is realized by 74LVC1G157GW multiplexer chip to select the vibration channel, when the high level is provided to the Select end of the chip, the PWM signal of the Input end is output to the Y end, so as to reach the gate of AO3400, so that the 3.3V voltage of the drain is provided to the vibration motor connected to the source, to realize the function of controlling the motor output stimulation.

[0202] The power conversion isolation module is a module for providing power support, using a rechargeable battery provided by the prosthesis for power supply, and each part of the circuit obtains corresponding voltage for power supply through the designed voltage conversion module.

[0203] The myoelectric prosthesis comprises a receiving cavity, a wrist joint motor with an encoder, a myoelectric signal analog-digital conversion module and a myoelectric collection electrode.

[0204] The motor driving module controls the steering and rotating speed of the wrist joint motor with an encoder in the myoelectric prosthesis, to realize the movement of the myoelectric prosthesis.

[0205] The main control module is electrically connected with the tactile stimulation module, and sets stimulation parameters according to the working state of the motor: adjusts the intensity, frequency and mode of the vibration and electro-tactile stimulation, which can be realized by buttons, switches or programmable electronic control systems, to generate mixed tactile stimulation acting on the upper arm of the prosthesis user.

[0206] The mixed tactile stimulation electrode array is made of flexible circuit board, which is composed of silicon substrate, thin film electrode and micro vibration motor, can perfectly fit the user's upper arm, and is safe and portable, has higher integration and more systematization than discrete vibration devices.

[0207] The flexible electrode array is electrically connected with the tactile stimulator through the wire and FPC connector, and contacts with the user's upper arm to transmit tactile stimulation.

[0208] The vibration electrode array uses 2 layers of flexible circuit board, with a board thickness of 0.12mm±0.03mm, a yellow cover film, a copper material on the surface, and a single size of 112.5mm*73mm, which meets the arm circumference length range of adult upper limbs.

[0209] The micro vibration motor selects a rotor motor with a diameter of 10mm, a thickness of 2.7mm, a rated rotating speed of 11000±2500rpm, a rated working voltage of 3.0V and a rated current of 80mA.

[0210] The micro vibration motor is driven by PWM square wave, the user can change the duty cycle of the PWM acting on the motor, and then change the effective voltage across the motor, to finally achieve the purpose of changing the vibration intensity of the motor. Each motor can realize independent regulation and control of parameters.

[0211] The working flow of the vibration stimulation and motor control system is as follows:

[0212] 1) Place a multi-channel flexible stimulation electrode array on the user's upper arm, and wear the myoelectric prosthesis on the limb;

[0213] 2) Place myoelectric acquisition electrodes at the position of a pair of antagonistic muscles on the user's forearm, and realize the flexion and extension movement of the wrist of the myoelectric prosthesis through the amplitude of the myoelectric signals of the two muscles;

[0214] 3) The encoder reads the motor rotation angle information in real time to monitor the prosthesis motion posture information in real time, and transmits the information to the master control module;

[0215] 4) The master control module controls the tactile stimulation module through a specific communication method, selects the stimulation output channel and sets the stimulation parameters; the vibration stimulation parameters include vibration frequency, vibration duration, vibration intensity, vibration interval duration; the stimulation waveform of the electro-tactile stimulation is a double-phase rectangular pulse, and the parameters include stimulation frequency, stimulation amplitude, stimulation pulse width, and stimulation delay.

[0216] 5) After the multi-channel flexible vibration stimulation electrode array receives the output signal, a specific mixed tactile stimulation acting on the upper arm of the prosthesis user is generated;

[0217] 6) After the user's upper limb feels the tactile stimulation, the corresponding action of the stimulation is performed or the corresponding action of the stimulation at the moment is recorded, the master control module detects the motor rotation state in real time and adjusts the stimulation parameters according to it, returns to step 4), until the current action is completed.

[0218] The wrist motion posture type of the prosthesis includes wrist flexion and wrist extension, and the angle range is 0° to 60°.

[0219] The system is powered by an 8V rechargeable battery, which is embedded in the prosthesis receiving cavity, and the stimulation intensity of the micro-vibration motor ranges from [0, 3.3V].

[0220] The amplitude range of the vibration stimulator output is [sensation threshold, 3.3V], and the modulation frequency range is [20, 200Hz]. The amplitude range of the electro-tactile stimulation sequence is [sensation threshold, pain threshold], and the modulation frequency range is [0, 200Hz].

[0221] A wrist joint proprioception reconstruction method based on sensory substitution:

[0222] 1) When the myoelectric prosthesis prosthesis movement posture information position is ST, it belongs to the initial position without stimulation, the position is E30, the electric tactile channel 1 is stimulated, the position is E15, the electric tactile channel 2 is stimulated, the position is F15, the electric tactile channel 3 is stimulated, and the position is F30, the electric tactile channel 4 is stimulated. E and F represent wrist extension and wrist flexion respectively, and 15 and 30 represent movement angles of 15° and 30° respectively. The stimulated channel changes with the change of the prosthesis angle.

[0223] 2) When the myoelectric prosthesis prosthesis movement posture information is wrist flexion, the electric tactile stimulation is sequentially performed in the channel in clockwise order, and the greater the angle, the farther the stimulated channel from the central axis; the vibration tactile stimulation simultaneously activates channel 3 and channel 4.

[0224] 3) When the myoelectric prosthesis prosthesis movement posture information is wrist extension, the electric tactile stimulation is sequentially performed in the channel in counterclockwise order, and the greater the angle, the farther the stimulated channel from the central axis; the vibration tactile stimulation simultaneously activates channel 1 and channel 2.

[0225] 4) When the myoelectric prosthesis prosthesis movement posture information is high speed, the vibration stimulation is correspondingly set to high frequency, when the myoelectric prosthesis prosthesis movement posture information is medium speed, the vibration stimulation is correspondingly set to medium frequency, and when the myoelectric prosthesis prosthesis movement posture information is low speed, the vibration stimulation is correspondingly set to low frequency.

[0226] Example 25:

[0227] Referring to Figures 1 to 6 A hybrid tactile stimulation system for providing prosthesis wrist movement information feedback to amputees, the system comprises a master control module, a motor drive module, a tactile stimulation module, a hybrid tactile stimulation electrode array module, and is embedded in a myoelectric prosthesis to provide sensory feedback to the user.

[0228] The hybrid tactile stimulation system is embedded in the internal receiving cavity of the myoelectric prosthesis during use, and the stimulation output part is closely connected with the user's arm, which is the core component of generating tactile stimulation.

[0229] The power consumption of the hybrid tactile stimulation system when not connected to the hybrid tactile stimulation electrode array, not connected to the Bluetooth, and not driven to move the prosthesis is 178.2mW, and the power consumption when not connected to the hybrid tactile stimulation electrode array and connected to the Bluetooth is 191.4mW, which has the advantage of low power consumption.

[0230] The size of the vibration stimulation-circuit board of the vibration stimulation-control system is 69.7mm*41.9mm, and the size of the vibration electrode array is 112.5mm*73mm, which has the advantages of miniaturization and portability.

[0231] The master module uses STM32F103RCT6 as the master chip of the system, has multiple peripherals built-in, including analog-to-digital converter, timer, interrupt controller, digital interface integrated circuit and various communication interfaces, and can help users to realize more flexible and complex functions. It is an embedded system with high performance, low cost, low power consumption and other advantages, which can provide control signals for the design.

[0232] The vibration stimulation part in the mixed haptic stimulation module realizes the gating of the vibration channel through the 74LVC1G157GW multiplexer chip. When a high level is provided to the Select end of the chip, the PWM signal at the Input end will be output to the Y end, thereby reaching the gate of the AO3400. Therefore, at the high level of the PWM wave, the 3.3V voltage at the drain will be provided to the vibration motor connected to the source, realizing the function of controlling the motor output stimulation.

[0233] The power conversion isolation module is a module that provides power support. It uses the 8V rechargeable battery provided by the prosthesis for power supply. Each part of the circuit obtains the corresponding voltage for power supply through the designed voltage conversion module: the power supply voltage of the myoelectric signal analog-to-digital conversion module, the master module and the Bluetooth communication module is 3.3V, the power supply voltage of the myoelectric collection electrode and the driving module is 5V, and the vibration motor is powered by 3.3V voltage within the rated working voltage range. The size of the electrohaptic stimulation is controlled by a constant current source. Since the impedance of the human body is floating, in order to ensure that the current size within the preset range can be provided, a voltage of 70V needs to be provided. Therefore, multiple voltage conversion circuits are designed for the system, including 8V to 12V, 12V to 70V, 12V to 5V and 5V to 3.3V.

[0234] The 8V to 12V circuit uses the TPS61089RNRR chip, which has a maximum output current of 7A, which can meet the power supply requirements of the system.

[0235] The 12V to 70V circuit adopts the DCDC switching power supply mode, and the circuit topology is a Boost circuit with feedback. The voltage level of this circuit is relatively high, and the system uses the MCP1650S chip, which can lift the voltage to more than 100V, and the allowed output is 5W, and the working static current is 120μA, which meets the design needs.

[0236] The 12V to 5V uses a high-performance Buck-type DCDC chip TPS563201 produced by Texas Instruments. The input voltage range of this chip is 2.95V to 17V, and the output voltage can be adjusted according to the external circuit, usually between 0.8V and 6V. In this circuit, two sets of resistance values connected to the VFB interface are set to set the output voltage to 5V, and the maximum output current can reach 3A.

[0237] The chip used in the 5V to 3.3V circuit is TLV70433, which is a low dropout linear regulator chip with low dropout and low quiescent current characteristics, and can be used to convert from 3.5V to 28V input voltage to 1.2V to 5.5V output voltage. The circuit using TLV70433 is very simple and easy to design, which can reduce the number of components and cost in the system.

[0238] Further, the power conversion isolation module also provides isolation function, separates the power supply and application circuit, improves the system safety. The power isolation function is realized by URB2412YMD-10WR3 isolation module, which realizes 12V-12V DCDC isolation, and the output power can reach 10W, and the isolation voltage can reach 1500VDC.

[0239] The myoelectric prosthesis comprises a receiving cavity, an encoder-equipped wrist joint motor, an electromyographic signal analog-to-digital conversion module, and electromyographic acquisition electrodes.

[0240] The motor drive module controls the steering and speed of the encoder-equipped wrist joint motor 4 in the myoelectric prosthesis to realize the movement of the myoelectric prosthesis.

[0241] The main control module is electrically connected with the tactile stimulation module, and the stimulation parameters are set according to the working state of the motor: adjusting the intensity, frequency and mode of vibration and electro-tactile stimulation parameters, which can be realized by buttons, switches or programmable electronic control system, to produce mixed tactile stimulation acting on the upper arm of the prosthesis user.

[0242] The mixed tactile stimulation electrode array is made of flexible circuit board, which is composed of silicon substrate, thin film electrode and micro vibration motor, can perfectly fit the user's upper arm, and is safe and portable, has higher integration and more systematization than discrete vibration devices.

[0243] The flexible electrode array is electrically connected with the tactile stimulator through the wire and FPC connector, and is in contact with the user's upper arm to transmit tactile stimulation.

[0244] The vibration electrode array uses 2 layers of flexible circuit board with a thickness of 0.12mm±0.03mm, yellow cover film, copper material on the surface, and a single size of 112.5mm*73mm, which meets the arm circumference length range of adult upper limbs.

[0245] The micro vibration motor selects a rotor motor with a diameter of 10mm, a thickness of 2.7mm, a rated speed of 11000±2500rpm, a rated working voltage of 3.0V, and a rated current of 80mA.

[0246] The micro-vibration motor uses PWM square wave drive, the user can change the duty cycle of the PWM acting on the motor, and then change the effective voltage across the motor, and finally achieve the purpose of changing the vibration intensity of the motor. Each motor can realize independent regulation of parameters.

[0247] The circuit system is as shown in the figure. Figure 2 The rechargeable battery is converted into voltage to supply power to each module. The prosthesis module includes a motor for controlling the movement of the prosthesis and an encoder for providing the movement angle information of the prosthesis, and an electromyographic signal analog-to-digital conversion module for driving the motor movement. The tactile stimulation generation module receives the prosthesis movement posture information transmitted by the electromyographic signal analog-to-digital conversion module and the control data transmitted by the upper computer through the Bluetooth communication module to generate a stimulation output signal.

[0248] When the 4 positions of wrist flexion and extension are mapped to the electrohaptic induced by different channels through the electrohaptic electrode array, the static position feeling and dynamic constant speed movement feeling are established according to the timing established according to the stimulation position. When the 3 speeds of wrist flexion and extension are mapped to the vibration induced by different frequencies through the vibration electrode array, the dynamic variable speed movement feeling is established according to the timing established according to the stimulation frequency and channel change.

[0249] Embodiment 26:

[0250] Referring to Figures 1 to 6 A hybrid tactile stimulation system for feedback of the movement of the wrist joint of the prosthesis for amputees, the system is embedded in the electromyographic prosthesis and electrically connected with the electromyographic prosthesis, and provides different modes of hybrid tactile stimulation according to the kinematic parameters of the prosthesis, helping the user to obtain sensory feedback while operating the prosthesis.

[0251] The system is embedded in the electromyographic prosthesis and electrically connected with the electromyographic prosthesis, and provides different modes of tactile stimulation according to the kinematic parameters of the prosthesis, helping the user to obtain sensory feedback while operating the prosthesis.

[0252] The hybrid tactile stimulation-control system comprises the following components: a master control module, a motor drive module, a vibration stimulation module, a vibration electrode array module, and a power conversion isolation module, which has the advantages of miniaturization and portability.

[0253] The hybrid tactile stimulation-control system is embedded in the receiving cavity inside the electromyographic prosthesis during use, and the stimulation output part is closely connected with the user's arm, which is the core component of generating tactile sensation.

[0254] The electromyographic prosthesis comprises a receiving cavity, a wrist joint motor with an encoder, an electromyographic signal analog-to-digital conversion module, and electromyographic acquisition electrodes.

[0255] The motor drive module controls the steering and rotating speed of the wrist joint motor 4 with an encoder in the myoelectric prosthesis, so as to realize the movement of the myoelectric prosthesis.

[0256] The master control module is electrically connected with the tactile stimulation module, and sets stimulation parameters according to the working state of the motor, such as the intensity, frequency and mode of the vibration and electro-tactile stimulation, which can be realized by buttons, switches or programmable electronic control systems, so as to generate mixed tactile stimulation acting on the upper arm of the user of the prosthesis.

[0257] The mixed tactile stimulation electrode array is made of a flexible circuit board, and is composed of a silicon substrate, a thin film electrode and a micro vibration motor, can be perfectly attached to the upper arm of the user, and is safe and portable, and has higher integration and more systematization than discrete vibration devices.

[0258] The flexible electrode array is electrically connected with the tactile stimulator through a wire and an FPC connector, and is in contact with the upper arm of the user to transmit the tactile stimulation.

[0259] The vibration electrode array uses a 2-layer flexible circuit board with a board thickness of 0.12mm±0.03mm, a yellow cover film and a copper material on the surface, and a single size of 112.5mm*73mm, which meets the arm circumference length range of the upper limbs of adults.

[0260] The micro vibration motor is selected to be a rotor motor with a diameter of 10mm, a thickness of 2.7mm, a rated rotating speed of 11000±2500rpm, a rated working voltage of 3.0V and a rated current of 80mA.

[0261] The micro vibration motor is driven by a PWM square wave, and the user can change the duty cycle of the PWM acting on the motor, and then change the effective voltage across the motor, so as to finally change the vibration intensity of the motor. Each motor can realize independent regulation and control of parameters.

[0262] On the basis of the mixed tactile stimulation-control system for movement sensory feedback and active control of the wrist of the myoelectric prosthesis, a sensory feedback method for mapping the wrist flexion and extension movement of the myoelectric prosthesis by using multi-channel mixed tactile stimulation is designed.

[0263] When the four positions of wrist flexion and extension are mapped as electro-tactile stimulation induced by different channels of the electro-tactile electrode array, the static position sensation and the dynamic constant speed movement sensation are established according to the time sequence established according to the stimulation positions. When the three speeds of wrist flexion and extension are mapped as vibration tactile stimulation induced by different frequencies of the vibration electrode array, the dynamic variable speed movement sensation is established according to the time sequence established according to the stimulation frequency and channel change.

[0264] The flexible hybrid tactile electrode array includes 4 micro-vibration motors and 4 electro-tactile stimulation electrodes, which are respectively denoted as vibration channels: VCH1, VCH2, VCH3, VCH4. Electro-stimulation channels: ECH1, ECH2, ECH3, ECH4. The vibration and electro-stimulation of the same channel number are at the same position of the electrode array. The two electrodes on the dorsal side of the upper arm correspond to the wrist extension direction of the prosthetic hand, while the two electrodes on the palmar side correspond to the wrist flexion direction. The greater the angle of movement, the more distant the activated stimulation channel is from the central axis.

[0265] The prosthetic movement posture information of the myoelectric prosthesis is mapped with different modes of tactile stimulation. When the myoelectric prosthesis movement posture information position is E30, the stimulation channel is ECH1, the position is E15, the stimulation channel is ECH2, the position is F15, the stimulation channel is ECH3, and the position is F30, the stimulation channel is ECH4. E and F represent wrist extension and wrist flexion respectively, and 15 and 30 represent movement angles of 15° and 30° respectively. The stimulation channel changes with the change of the prosthesis angle.

[0266] When the myoelectric prosthesis moves in the wrist extension direction from 0° to 30°, two channels VCH1 and VCH2 are activated. When the myoelectric prosthesis moves in the wrist flexion direction from 0° to 30°, two channels VCH3 and VCH4 are activated.

[0267] In the mapping mode of the electro-tactile stimulation channel and the constant speed movement information of the prosthesis, the vibration stimulation duration of each channel is 0.5 seconds, the stimulation frequency is fixed, and the range is between [10, 200Hz], the stimulation intensity is fixed, and the range is between [0, 8mA].

[0268] In the mapping mode of the vibration stimulation frequency and the variable speed movement information of the prosthesis, when the myoelectric prosthesis performs wrist flexion and extension movement, each channel adopts a continuous vibration mode, and the vibration stimulation frequency changes with the change of the movement speed. When moving at high speed, the vibration stimulation frequency corresponds to a high frequency of 200Hz. When moving at medium speed, the vibration stimulation frequency corresponds to a medium frequency of 100Hz. When moving at low speed, the vibration stimulation frequency corresponds to a low frequency of 50Hz.

Claims

1. A hybrid haptic stimulation system for feeding back prosthesis wrist motion information to an amputee, characterized in that, The mixed tactile stimulation system interacts with the myoelectric prosthesis to provide the user with sensory feedback of the wrist. The myoelectric prosthesis comprises a receiving cavity, a myoelectric collection electrode (1), and a wrist joint motor (4) with an encoder. The mixed tactile stimulation system comprises a myoelectric signal analog-digital conversion module (2), a motor driving module (3), a main control module (5), a tactile stimulation module (6), and a multi-channel mixed tactile stimulation electrode array module (7). The multi-channel mixed tactile stimulation electrode array module (7) comprises n micro-vibration motors (9), n electric tactile stimulation electrodes, an FPC connector (10), and a flexible circuit board, wherein n is a positive integer. The micro-vibration motor (9) is used to generate vibration stimulation on the user's upper arm. The electric tactile stimulation electrode is attached to the user's upper arm of the myoelectric prosthesis to generate electric tactile stimulation on the user's upper arm. The FPC connector (10) connects the n micro-vibration motors and the n electric tactile stimulation electrodes with the tactile stimulation module (6) through a wire to realize multi-channel output of mixed tactile stimulation. One surface of the flexible circuit board is spaced apart with n micro-vibration motors (9), and the other surface is spaced apart with n electric tactile stimulation electrodes. The myoelectric collection electrode (1) acquires two-channel myoelectric signals of a pair of antagonistic muscles of the user's forearm. The myoelectric signal analog-digital conversion module (2) performs analog-digital conversion on the two-channel myoelectric signals to obtain corresponding digital signals, and generates a prosthesis motion control instruction based on the corresponding digital signals of the two-channel myoelectric signals. The myoelectric signal analog-digital conversion module (2) generates a motor driving signal and sends it to the main control module (5). After receiving the motor driving signal, the main control module (5) controls the motor driving module (3) to control the wrist joint motor (4) with an encoder in the myoelectric prosthesis to move according to the prosthesis motion control instruction. When the myoelectric prosthesis moves, the encoder of the wrist joint motor (4) with an encoder feeds back the motor rotation angle to monitor the prosthesis motion posture information (8) in real time and transmit the prosthesis motion posture information (8) to the main control module (5). The main control module (5) encodes the prosthesis motion posture information (8) into a tactile stimulation pattern to control the tactile stimulation module (6) to output a tactile stimulation sequence on the multi-channel mixed tactile stimulation electrode array module (7).

2. A hybrid haptics stimulation system for providing feedback on wrist motion information of a prosthetic for an amputee according to claim 1, characterized in that The system further comprises a power conversion isolation module. The power conversion isolation module supplies power to the myoelectric collection electrode (1), the myoelectric signal analog-digital conversion module (2), the motor driving module (3), the wrist joint motor (4) with an encoder, the main control module (5), the tactile stimulation module (6), and the multi-channel mixed tactile stimulation electrode array module (7). The power conversion isolation module isolates the power supply of the myoelectric collection electrode (1) and the myoelectric signal analog-digital conversion module (2) from the power supply of the motor driving module (3), the wrist joint motor (4) with an encoder, the main control module (5), the tactile stimulation module (6), and the multi-channel mixed tactile stimulation electrode array module (7).

3. The hybrid haptics stimulation system for providing amputees with information about the movement of the wrist of a prosthesis according to claim 1, characterized in that The prosthesis motion control instruction includes the steering and rotation speed of the myoelectric prosthesis wrist joint.

4. The hybrid haptics stimulation system of claim 1, wherein, The movement type of the myoelectric artificial limb includes wrist flexion and wrist extension.

5. The hybrid haptics stimulation system of claim 1, wherein, The positions of the micro-vibration motors (9) on the flexible circuit board correspond to the positions of the electrohaptic stimulation electrodes.

6. The hybrid haptics stimulation system of claim 1, wherein, The micro-vibration motor (9) receives a voltage amplitude range of [0, 3.3V].

7. The hybrid haptics stimulation system of claim 1, wherein, The stimulation intensity of the electrohaptic stimulation electrode ranges from [0, 8mA].

8. The hybrid haptics stimulation system of claim 1, wherein, The amplitude of the haptic stimulation sequence output by the haptic stimulation module (6) ranges from [b, 3.3V], the modulation frequency ranges from [20Hz, 200Hz], the amplitude of the electrohaptic stimulation sequence ranges from [c, d], and the modulation frequency ranges from [0, 200Hz], wherein b is the vibration sensation threshold, c is the electrohaptic sensation threshold, and d is the electrohaptic pain threshold.

9. The hybrid haptics stimulation system for providing amputees with information about the movement of the wrist of a prosthesis according to claim 1, characterized in that The parameters of the vibration stimulation include vibration frequency, vibration duration, vibration intensity, and vibration interval duration.

10. The hybrid haptics stimulation system for providing amputees with information about the movement of the wrist of a prosthesis according to claim 1, characterized in that The stimulation waveform of the electrohaptic stimulation includes a biphasic rectangular pulse. The parameters of the electrohaptic stimulation include stimulation frequency, stimulation amplitude, stimulation pulse width, and stimulation delay.

Images