Myoelectric control ankle joint rehabilitation system

Abstract

The invention relates to a myoelectric control ankle joint rehabilitation system which comprises a flexible ankle joint rehabilitation exoskeleton and a self-adaptive impedance control component, and a foot support of the flexible ankle joint rehabilitation exoskeleton is connected with an upper fixing assembly through a middle supporting assembly. The flexible ankle joint rehabilitation exoskeleton drives a foot support to rotate through a dorsiflexion motor, a plantar flexion motor, an introversion / extroversion motor and an abduction / adduction motor, so that an ankle joint completes one of dorsiflexion, plantar flexion, introversion, extroversion, abduction and adduction motions; the self-adaptive impedance control component is used for constructing a human body active motion intention by acquiring electromyographic signals of calf muscles so as to control the motion of the flexible ankle joint rehabilitation exoskeleton and performing self-adaptive adjustment on the impedance of the flexible ankle joint rehabilitation exoskeleton in combination with human body passive motion information. An exoskeleton wearable design is adopted, so that the device has the characteristics of convenience and lightness, and an active and passive combined training mode is also adopted, so that the ankle joint rehabilitation effect is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of medical devices, and in particular to an ankle joint rehabilitation system controlled by myoelectricity. Background Art

[0002] Ankle injury is one of the common types of sports injuries in daily life. This injury may cause clinical symptoms such as hemiplegia, ligament injury, and atrophy of ankle-related muscles. Ankle injuries are common among women who often wear high heels, the elderly, and athletes. Fall injuries, sprains, etc. can cause ankle injuries.

[0003] At present, most ankle rehabilitation equipment is traditional strap-type rehabilitation equipment, sitting or lying rehabilitation equipment, etc. Since patients do not participate much in the ankle rehabilitation training using traditional ankle rehabilitation equipment, the ankle rehabilitation effect is poor and the rehabilitation cycle is long. In addition, the sitting or lying rehabilitation equipment will cause inconvenience to the patient's daily life.

[0004] Therefore, there is an urgent need for a highly adaptable and flexible ankle rehabilitation device to improve the effect of rehabilitation treatment for patients and help them recover their walking ability faster. Summary of the invention

[0005] 1. Technical issues to be resolved

[0006] In view of the above-mentioned shortcomings and deficiencies of the prior art, the present invention provides a myoelectrically controlled ankle joint rehabilitation system, which solves the technical problems of poor rehabilitation effect and low patient participation of traditional ankle joint rehabilitation equipment.

[0007] (II) Technical solution

[0008] In order to achieve the above object, the main technical solutions adopted by the present invention include:

[0009] The embodiment of the present invention provides a myoelectrically controlled ankle joint rehabilitation system, comprising: a flexible ankle joint rehabilitation exoskeleton and an adaptive impedance control component;

[0010] The flexible ankle joint rehabilitation exoskeleton includes: a footrest, an upper fixing component, an intermediate supporting component, a transmission component, a dorsiflexion motor, a plantar flexion motor, an abduction / adduction motor, and an inversion / eversion motor;

[0011] The footrest and the upper fixing assembly are used to fix and support the lower limbs of the human body;

[0012] The middle support component is connected to the footrest and the upper fixing component respectively, and a carbon fiber plate is provided on the middle support component to enable the flexible ankle joint rehabilitation exoskeleton to complete three-degree-of-freedom movement;

[0013] The dorsiflexion motor, plantar flexion motor and inversion / eversion motor are all arranged in the upper fixed assembly and connected to the footrest through the driving rope in the transmission assembly, and are used to drive the ankle joint to perform one of dorsiflexion, plantar flexion, inversion and eversion when the driving rope is retracted or released;

[0014] The abduction / adduction motor is arranged in the middle support assembly and connected to the footrest through a connecting shaft in the transmission assembly, so as to drive the ankle joint to perform abduction or adduction movement when the connecting shaft rotates;

[0015] The adaptive impedance control component is used to control the movement of the flexible ankle joint rehabilitation exoskeleton by acquiring the human body's active movement intention constructed by the electromyographic signal of the calf muscle, and adaptively adjust the impedance of the flexible ankle joint rehabilitation exoskeleton in combination with the human body's passive movement information.

[0016] Optionally, the upper fixing assembly includes: a front fixing plate, a rear fixing plate, a first motor mounting plate, a second motor mounting plate, an inward / outward motor support plate, a first transmission plate, a second transmission plate, a third transmission plate, and a fourth transmission plate;

[0017] The front fixing plate and the rear fixing plate are connected by elastic straps on the strap holes, and are used to fix and support the lower legs of the human body;

[0018] A first transmission plate and a second transmission plate are arranged on both sides of the first motor mounting plate and connected to the front fixing plate, and the dorsiflexion motor is mounted on the first motor mounting plate;

[0019] A third transmission plate and a fourth transmission plate are arranged on both sides of the second motor mounting plate and are connected to the rear fixing plate, the plantar flexion motor is mounted on the second motor mounting plate, and the varus / valgus motor is mounted on the second motor mounting plate through two varus / valgus motor support plates;

[0020] The first transmission plate, the second transmission plate, the third transmission plate and the fourth transmission plate are all riveted with bearings.

[0021] Optionally, the transmission assembly includes: a first drive rope, a second drive rope, a third drive rope, a fourth drive rope, a first wire wheel, a second wire wheel, a third wire wheel, a fourth wire wheel, a first drive rod, a second drive rod and a connecting shaft;

[0022] One end of the first driving rope is connected to the first connecting hole of the foot support, and the other end of the first driving rope is connected to the first wire wheel arranged on the rotating shaft of the dorsiflexion motor;

[0023] One end of the second driving rope is connected to the second connecting hole of the foot support, and the other end of the second driving rope is connected to the second wire wheel arranged on the rotating shaft of the plantar flexion motor;

[0024] The first driving rod sequentially passes through the bearing on the first transmission plate, the third wire wheel, the bearing on the third transmission plate and the left rotating shaft of the inversion / outversion motor to engage with the gears, and the third wire wheel is connected to the third connecting hole of the foot support through the third driving rope;

[0025] The second driving rod sequentially passes through the bearing on the second transmission plate, the fourth wire wheel, the bearing on the fourth transmission plate and the right rotating shaft of the inversion / outversion motor to engage with the gears, and the fourth wire wheel is connected to the fourth connecting hole of the foot support through the fourth driving rope;

[0026] One end of the connecting shaft is connected with the rotating shaft of the abduction / adduction motor by transition fit and is locked by a fastening screw, and the other end is fixedly connected with the foot support.

[0027] The first driving rod and the second driving rod rotate in opposite directions under the drive of the inward / outward turning motor.

[0028] Optionally, the intermediate support assembly includes: a first lower support plate, a second lower support plate, a third lower support plate, a first carbon fiber plate, a second carbon fiber plate, a third carbon fiber plate, a first upper support plate, a second upper support plate and a third upper support plate;

[0029] The first lower support plate is arranged on the left side of the footrest, the first lower support plate is staggeredly connected with the first upper support plate through the first carbon fiber plate, and the first upper support plate is also movably connected with the upper fixing assembly through the waist-shaped hole;

[0030] The second lower support plate is arranged on the right side of the footrest, the second lower support plate is staggeredly connected with the second upper support plate through the second carbon fiber plate, and the second upper support plate is also movably connected with the upper fixing assembly through the waist-shaped hole;

[0031] The third lower support plate is provided with an extension / retraction motor. The third lower support plate is staggeredly connected to the third upper support plate through a third carbon fiber plate. The third upper support plate is also connected to the upper fixing assembly.

[0032] Optionally, the myoelectrically controlled ankle rehabilitation system includes: a wireless transmission module, a single-chip microcomputer, and a motor driver;

[0033] The wireless transmission module is connected to the single chip microcomputer and is used to transmit the control signal of the adaptive impedance control unit to the single chip microcomputer;

[0034] The single-chip microcomputer is connected to the motor driver and is used to generate a motor control instruction and send it to the motor driver when receiving the control signal of the adaptive impedance control component. The motor driver drives the dorsiflexion motor, plantar flexion motor, inversion / eversion motor and abduction / adduction motor to rotate to drive the flexible ankle joint rehabilitation exoskeleton to complete the ankle joint dorsiflexion / plantar flexion movement, inversion / eversion movement and abduction / adduction movement.

[0035] Optionally, the adaptive impedance control component includes: a signal detection module, an electromyographic signal processing module, an ankle joint angle prediction module, a motor control module and an adaptive impedance adjustment module;

[0036] The signal detection module is used to collect the electromyographic signals of the calf muscles and the passive motion information of the human body;

[0037] The electromyographic signal processing module is connected to the signal detection module and is used to pre-process and extract features of the electromyographic signal to obtain multiple feature values ​​of the electromyographic signal;

[0038] The ankle joint angle prediction module is connected to the electromyographic signal processing module and is used to input multiple characteristic values ​​into a pre-trained neural network model to predict the ankle joint angle and obtain the ankle joint angle prediction result;

[0039] The motor control module and the ankle joint angle prediction module are used to convert the human active movement intention constructed based on the ankle joint angle prediction result into the robot movement model to obtain the motor control signal;

[0040] The adaptive impedance adjustment module is connected to the motor control module and the signal detection module respectively, and is used to adjust the inertia, stiffness and damping model parameters of the flexible ankle joint rehabilitation exoskeleton in real time based on the human body's active movement intention and the human body's passive movement information.

[0041] Optionally, the information detection unit includes: a fabric electrode, a pressure sensor, an acceleration sensor and an angular displacement sensor;

[0042] The fabric electrodes can be adjusted according to the wearer's calf muscle distribution information to collect the electromyographic signals of the tibialis anterior, gastrocnemius, gastrocnemius lateralis, peroneus longus and soleus muscles;

[0043] The pressure sensor is used to collect the pressure signal of footsteps;

[0044] The acceleration sensor is used to collect the acceleration signal of the ankle;

[0045] The angular displacement sensor is used to collect the angle signal of the ankle.

[0046] Optionally, the electromyographic signal processing module includes: an empirical mode decomposition unit, a noise reduction unit, an electromyographic signal reconstruction unit and a feature extraction unit connected in sequence;

[0047] The empirical mode decomposition unit is used to decompose the electromyographic signal based on the empirical mode decomposition algorithm to obtain multiple intrinsic mode functions;

[0048] The noise reduction unit is used to remove noise and interference in each intrinsic mode function based on a soft threshold algorithm;

[0049] The electromyographic signal reconstruction unit is used to reconstruct the intrinsic mode function after removing noise and interference to obtain the electromyographic signal after noise reduction;

[0050] The feature extraction unit is used to perform time domain, frequency domain and nonlinear analysis on the denoised electromyographic signal to obtain a plurality of time domain eigenvalues, a plurality of frequency domain eigenvalues ​​and a plurality of nonlinear eigenvalues.

[0051] Optionally, the method steps of the denoising unit for denoising the intrinsic mode function include:

[0052] Compare the coefficient of each eigenmode function with the set threshold;

[0053] If the comparison result shows that the coefficient of the intrinsic mode function is less than the set threshold, the coefficient of the intrinsic mode function is modified to 0;

[0054] If the comparison result shows that the coefficient of the intrinsic mode function is not less than the set threshold, the coefficient of the intrinsic mode function is retained.

[0055] Optionally, the adaptive impedance control unit further includes: an information storage module, an information display module and a neural network construction module;

[0056] The information storage module is connected to the signal detection module and is used to store the pressure signal and the angle signal;

[0057] The information display module is connected to the signal detection module and is used to display the pressure signal and the angle signal;

[0058] The neural network construction module is connected with the signal detection module and the electromyographic signal processing module, and is used to construct an initial neural network model based on multiple eigenvalues, and to obtain a neural network model by training the initial neural network model through electromyographic signals and angle signals and verifying the accuracy of the initial neural network model.

[0059] (III) Beneficial effects

[0060] The beneficial effects of the present invention are: compared with traditional ankle joint rehabilitation equipment, the present invention adopts a flexible exoskeleton wearable design, making it more ergonomic in force structure. In particular, the middle support component also adopts a carbon fiber plate for support connection, so that the flexible ankle joint rehabilitation exoskeleton can maintain no movement in other degrees of freedom when moving in one or more degrees of freedom, and reduce the weight of the patient during rehabilitation training.

[0061] At the same time, the flexible ankle joint rehabilitation exoskeleton of the present invention also uses multiple motors as the active power source of the exoskeleton, and can accurately assist patients in performing dorsiflexion / plantar flexion, inversion / eversion and abduction / adduction movements under the control instructions generated by the adaptive impedance control component based on the active movement intention of the human body.

[0062] In addition, the adaptive impedance control unit of the present invention adopts a technical solution to adaptively adjust the impedance of the flexible ankle joint rehabilitation exoskeleton based on the human body's active movement intention and the human body's passive movement information, thereby achieving seamless connection between active excitation and interactive assistance of the flexible ankle joint rehabilitation exoskeleton, enabling the patient's ankle joint to undergo active and passive training, and improving the ankle joint rehabilitation effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0063] Figure 1 A schematic diagram of the structure of an ankle joint rehabilitation system controlled by electromyography provided by one embodiment of the present invention;

[0064] Figure 2 A left view of a flexible ankle joint rehabilitation exoskeleton provided by an embodiment of the present invention;

[0065] Figure 3 A right side view of a flexible ankle joint rehabilitation exoskeleton provided by an embodiment of the present invention;

[0066] Figure 4 An exploded view of a first motor mounting plate in a flexible ankle joint rehabilitation exoskeleton provided in an embodiment of the present invention;

[0067] Figure 5 An exploded view of a second motor mounting plate in a flexible ankle joint rehabilitation exoskeleton provided in an embodiment of the present invention;

[0068] Figure 6 This is a schematic diagram of the foot support structure of a flexible ankle joint rehabilitation exoskeleton provided in one embodiment of the present invention.

[0069] [Description of Reference Numerals]

[0070] 100: footrest; 101: first connection hole; 102: second connection hole; 103: third connection hole; 104: fourth connection hole; 105: strap hole;

[0071] 201: front fixing plate; 202: rear fixing plate; 203: first motor mounting plate; 204: second motor mounting plate; 205: first transmission plate; 206: second transmission plate; 207: third transmission plate; 208: fourth transmission plate; 209: inward / outward motor support plate;

[0072] 301: first lower support plate; 302: second lower support plate; 303: third lower support plate; 304: first carbon fiber plate; 305: second carbon fiber plate; 306: third carbon fiber plate; 307: first upper support plate; 308: second upper support plate; 309: third upper support plate

[0073] 401: first drive rope; 402: second drive rope; 403: third drive rope; 404: fourth drive rope; 405: first line wheel; 406: second line wheel; 407: third line wheel; 408: fourth line wheel; 409: first drive rod; 410: second drive rod; 411: connecting shaft; 412: bearing;

[0074] 500: Dorsiflexion motor;

[0075] 600: plantar flexion motor;

[0076] 700: Inward / outward motor;

[0077] 800: Abduction / adduction motor. DETAILED DESCRIPTION

[0078] In order to better explain the present invention and facilitate understanding, the present invention is described in detail below through specific implementation modes in conjunction with the accompanying drawings.

[0079] It should be noted that all directional indications in the embodiments of the present invention (such as up, down, left, right, front, back, etc.) are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0080] like Figure 1-6 As shown, an embodiment of the present invention proposes an electromyographically controlled ankle rehabilitation system, which includes: a flexible ankle rehabilitation exoskeleton and an adaptive impedance control component. The flexible ankle rehabilitation exoskeleton includes: a footrest 100, an upper fixing component, an intermediate support component, a transmission component, a dorsiflexion motor 500, a plantar flexion motor 600, an abduction / adduction motor 700, and an inversion / valgus motor 800; the footrest 100 and the upper fixing component are used to fix and support the lower limbs of the human body; the intermediate support component is respectively connected to the footrest 100 and the upper fixing component, and a carbon fiber plate is provided on the intermediate support component to enable the flexible ankle rehabilitation exoskeleton to complete three-degree-of-freedom movement; the dorsiflexion motor The motor 500, the plantar flexion motor 600 and the inversion / valgus motor 800 are all arranged in the upper fixed assembly and connected to the footrest 100 through the driving rope in the transmission assembly, and are used to drive the ankle joint to perform one of dorsiflexion, plantar flexion, inversion and eversion when the driving rope is retracted and released; the abduction / adduction motor 700 is arranged in the middle support assembly and connected to the footrest 100 through the connecting shaft 411 in the transmission assembly, and is used to drive the ankle joint to perform abduction or adduction when the connecting shaft 411 rotates. The adaptive impedance control component is used to control the movement of the flexible ankle joint rehabilitation exoskeleton by acquiring the human active movement intention constructed by the electromyographic signal of the calf muscle, and adaptively adjust the impedance of the flexible ankle joint rehabilitation exoskeleton in combination with the human passive movement information.

[0081] The flexible ankle rehabilitation exoskeleton adopts a wearable design, making it more ergonomic in its force structure. In particular, its middle support component also uses a carbon fiber plate for support connection, so that when the flexible ankle rehabilitation exoskeleton moves in one or more degrees of freedom, it can maintain no movement in other degrees of freedom, and reduce the weight of the patient during rehabilitation training.

[0082] At the same time, the flexible ankle rehabilitation exoskeleton also uses multiple motors as the active power source of the exoskeleton, and can accurately assist patients in dorsiflexion / plantar flexion, inversion / eversion and abduction / adduction movements under the control instructions generated by the adaptive impedance control component based on the active movement intention of the human body.

[0083] In addition, the adaptive impedance control unit adopts a technical solution to adaptively adjust the impedance of the flexible ankle rehabilitation exoskeleton based on the human body's active movement intention and the human body's passive movement information, thereby achieving seamless connection between active excitation and interactive assistance of the flexible ankle rehabilitation exoskeleton, enabling the patient's ankle joint to undergo active and passive training, and improving the ankle rehabilitation effect.

[0084] In order to better understand the above technical solution, exemplary embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. Although exemplary embodiments of the present invention are shown in the accompanying drawings, it should be understood that the present invention can be implemented in various forms and should not be limited by the embodiments described herein. On the contrary, these embodiments are provided to enable a clearer and more thorough understanding of the present invention and to fully convey the scope of the present invention to those skilled in the art.

[0085] First, the upper fixing assembly of the flexible ankle joint rehabilitation exoskeleton includes: a front fixing plate 201, a rear fixing plate 202, a first motor mounting plate 203, a second motor mounting plate 204, an inversion / valgus motor 800 support plate 209, a first transmission plate 205, a second transmission plate 206, a third transmission plate 207 and a fourth transmission plate 208.

[0086] The front fixing plate 201 and the rear fixing plate 202 are respectively installed on the front and rear sides of the calf joint and connected by elastic bands arranged on the bandage holes 105 of the front fixing plate 201 and the rear fixing plate 202. The front fixing plate 201 and the rear fixing plate 202 are fixed at the calf knee joint with a certain distance, and are tightened by the elastic band to adapt to the calf diameters of different patients. The calf is wrapped with elastic fabric between the front fixing plate 201 and the rear fixing plate 202 to protect the calf joint from being crushed by the front fixing plate 201 and the rear fixing plate 202.

[0087] A first transmission plate 205 and a second transmission plate 206 are provided on both sides of the first motor mounting plate 203 and connected to the front fixing plate 201 . The dorsiflexion motor 500 is mounted on the first motor mounting plate 203 .

[0088] A third transmission plate 207 and a fourth transmission plate 208 are provided on both sides of the second motor mounting plate 204 and connected to the rear fixing plate 202. The plantar flexion motor 600 is mounted on the second motor mounting plate 204. The inversion / valgus motor 800 is mounted on the second motor mounting plate 204 through two inversion / valgus motor support plates 209.

[0089] The first transmission plate 205, the second transmission plate 206, the third transmission plate 207 and the fourth transmission plate 208 are all riveted with bearings 412. The bearings 412 on the first transmission plate 205 and the bearings 412 on the third transmission plate 207 are arranged on a central axis, and the bearings 412 on the second transmission plate 206 and the bearings 412 on the fourth transmission plate 208 are arranged on a central axis.

[0090] Secondly, the transmission assembly of the flexible ankle joint rehabilitation exoskeleton includes: a first driving rope 401, a second driving rope 402, a third driving rope 403, a fourth driving rope 404, a first wire wheel 405, a second wire wheel 406, a third wire wheel 407, a fourth wire wheel 408, a first driving rod 409, a second driving rod 410 and a connecting shaft 411;

[0091] One end of the first driving rope 401 is connected to the first connection hole 101 of the foot support 100, and the other end of the first driving rope 401 is connected to the first wire pulley 405 set on the rotating shaft of the dorsiflexion motor 500. One end of the second driving rope 402 is connected to the second connection hole 102 of the foot support 100, and the other end of the second driving rope 402 is connected to the second wire pulley 406 set on the rotating shaft of the plantar flexion motor 600.

[0092] In a specific embodiment, when the dorsiflexion motor 500 rotates forward, the first wire wheel 405 rotates forward and drives the first driving rope 401 to contract, and the plantar flexion motor 600 rotates reversely to drive the second driving rope 402 set on the second wire wheel 406 to be lowered, and the contraction of the first driving rope 401 and the lowering of the second driving rope 402 can drive the footrest 100 to rotate and assist the ankle joint to complete the dorsiflexion movement. When the dorsiflexion motor 500 rotates reversely, the first wire wheel 405 rotates forward and drives the first driving rope 401 to be lowered, and the plantar flexion motor 600 rotates forward to drive the second driving rope 402 set on the second wire wheel 406 to contract, and the lowering of the first driving rope 401 and the contraction of the second driving rope 402 can drive the footrest 100 to rotate and assist the ankle joint to complete the plantar flexion movement. Among them, the angle range of the dorsiflexion movement is 20° to 0°, and the required tension is 25.25N; the angle range of the plantar flexion movement is -50° to 0°, and the required tension is 25.16N.

[0093] The first driving rod 409 sequentially passes through the bearing 412 on the first transmission plate 205, the third wire wheel 407, and the bearing 412 on the third transmission plate 207 to mesh with the left rotating shaft of the inversion / external motor 800, and the third wire wheel 407 is connected to the third connecting hole 103 of the foot support 100 through the third driving rope 403. The second driving rod 410 sequentially passes through the bearing 412 on the second transmission plate 206, the fourth wire wheel 408, and the bearing 412 on the fourth transmission plate 208 to mesh with the right rotating shaft of the inversion / external motor 800, and the fourth wire wheel 408 is connected to the fourth connecting hole 104 of the foot support 100 through the fourth driving rope 404. Among them, the first driving rod 409 and the second driving rod 410 rotate in opposite directions under the drive of the inversion / external motor 800.

[0094] In a specific embodiment, the inversion / external motor 800 drives the first driving rod 409 and the second driving rod 410 to rotate in the opposite direction, and at the same time, the third wire wheel 407 on the first driving rod 409 and the fourth wire wheel 408 on the second driving rod 410 rotate in the opposite direction, thereby completing the fourth driving rope 404 lowering when the third driving rope 403 is contracted and the fourth driving rope 404 contracting when the third driving rope 403 is lowered, and further driving the footrest 100 to rotate to assist the ankle joint in inversion / external movement. The angle range of the inversion / external movement is -12° to 12°, the tension required for the inversion movement is 18.46N, and the tension required for the external movement is 12.93N.

[0095] One end of the connecting shaft 411 is connected to the rotating shaft of the abduction / adduction motor 700 by transition fit and is locked with a fastening screw, and the other end is fixedly connected to the footrest 100. The rotation of the rotating shaft of the abduction / adduction motor 700 drives the connecting shaft 411 to rotate, and the rotation of the connecting shaft 411 drives the footrest 100 to rotate to assist the ankle joint machine in abduction / adduction movement. Among them, the angle range of abduction / adduction movement is -10° to 10°, the torque required to complete the abduction movement is 11.438N, and the torque required to complete the eversion movement is 12.93N.

[0096] Furthermore, the middle support component of the flexible ankle rehabilitation exoskeleton includes: a first lower support plate 301, a second lower support plate 302, a third lower support plate 303, a first carbon fiber plate 304, a second carbon fiber plate 305, a third carbon fiber plate 306, a first upper support plate 307, a second upper support plate 308 and a third upper support plate 309.

[0097] The first lower support plate 301 is arranged on the left side of the footrest 100, and the first lower support plate 301 is staggeredly connected to the first upper support plate 307 through the first carbon fiber plate 304, and the first upper support plate 307 is also movably connected to the upper fixed assembly through the waist-shaped hole. The second lower support plate 302 is arranged on the right side of the footrest 100, and the second lower support plate 302 is staggeredly connected to the second upper support plate 308 through the second carbon fiber plate 305, and the second upper support plate 308 is also movably connected to the upper fixed assembly through the waist-shaped hole. The waist-shaped hole design on the upper part of the first upper support plate 307 and the second upper support plate 308 is designed so that when the distance between the upper fixed assembly changes with the different diameters of the patient's calves, it can be accurately installed and adapted to the leg size of most patients. The third lower support plate 303 is provided with an abduction / adduction motor 700, and the third lower support plate 303 is staggeredly connected to the third upper support plate 309 through the third carbon fiber plate 306, and the third upper support plate 309 is also connected to the upper fixed assembly. The first carbon fiber plate 304, the second carbon fiber plate 305 and the third carbon fiber plate 306 are all connected by waist-shaped holes, so as to be able to adjust the installation position and installation angle of the first carbon fiber plate 304, the second carbon fiber plate 305 and the third carbon fiber plate 306 within a certain range, so that the first carbon fiber plate 304, the second carbon fiber plate 305 and the third carbon fiber plate 306 can better realize three-degree-of-freedom movement.

[0098] Then, the adaptive impedance control component includes: a signal detection module, an electromyographic signal processing module, an ankle joint angle prediction module, a motor control module and an adaptive impedance adjustment module. The signal detection module is used to collect electromyographic signals of calf muscles and human passive motion information; the electromyographic signal processing module is connected to the signal detection module, and is used to pre-process and extract features of the electromyographic signals to obtain multiple characteristic values ​​of the electromyographic signals; the ankle joint angle prediction module is connected to the electromyographic signal processing module, and is used to input multiple characteristic values ​​into a pre-trained neural network model to predict the ankle joint angle and obtain the ankle joint angle prediction result; the motor control module and the ankle joint angle prediction module are used to convert the human active motion intention constructed based on the ankle joint angle prediction result into a robot motion model to obtain the motor control signal; the adaptive impedance adjustment module is respectively connected to the motor control module and the signal detection module, and is used to adjust the inertia, stiffness and damping model parameters of the flexible ankle joint rehabilitation exoskeleton in real time based on the human active motion intention and human passive motion information.

[0099] Further explanation, the information detection unit includes: a fabric electrode, a pressure sensor, an acceleration sensor and an angular displacement sensor; the fabric electrode can be adjusted according to the wearer's calf muscle distribution information to collect the electromyographic signals of the tibialis anterior, gastrocnemius internalis, gastrocnemius externalis, peroneus longus and soleus muscles; the pressure sensor is used to collect the pressure signal of the footstep; the acceleration sensor is used to collect the acceleration signal of the ankle; the angular displacement sensor is used to collect the angle signal of the ankle.

[0100] The fabric motor is divided into a reference electrode and a working electrode. The reference electrode should be located at the bone protrusion or the tendon of the muscle that does not participate in the test movement, in order to exclude the voltage that is not generated by the human body and provide a reference voltage. The working electrode should be located in the middle of the muscle belly, along the direction of the muscle spindle, and avoid the following three positions: First, the tendon, where the number of muscle fibers is the least and the shape is thin, and the electromyographic signal collected by the tendon is relatively weak; second, the edge of the muscle, the electrode placed at the edge is very likely to collect the electromyographic signal of the adjacent muscle, which confuses the muscle analysis; third, the muscle movement point, that is, the threshold point for inducing surface electromyographic signals, the muscle movement point is relatively sensitive and the collection process is easily disturbed.

[0101] To further illustrate, the electromyographic signal processing module includes: an empirical mode decomposition unit, a noise reduction unit, an electromyographic signal reconstruction unit and a feature extraction unit which are connected in sequence.

[0102] The empirical mode decomposition unit is used to decompose the electromyographic signal based on the empirical mode decomposition algorithm. The number of decomposition layers is 6, and 6 intrinsic mode functions are obtained. Each intrinsic mode function represents a different frequency component.

[0103] The noise reduction unit is used to remove noise and interference in each intrinsic mode function based on the soft threshold algorithm. The coefficient of each intrinsic mode function is compared with the set threshold; if the comparison result shows that the coefficient of the intrinsic mode function is less than the set threshold, the coefficient of the intrinsic mode function is modified to 0; if the comparison result shows that the coefficient of the intrinsic mode function is not less than the set threshold, the coefficient of the intrinsic mode function is retained.

[0104] The electromyographic signal reconstruction unit is used to reconstruct the intrinsic mode function after removing noise and interference to obtain the electromyographic signal after noise reduction.

[0105] The feature extraction unit is used to analyze the denoised EMG signal in time domain, frequency domain and nonlinearity and extract features. Eleven time domain features that can reflect the important information of surface EMG signals are selected, including mean absolute value (MAV), root mean square value (RMS), waveform length (WL), slope sign changes (SSC), autoregressive coefficient (AR), signal energy (SSI), Willison amplitude (WAMP), mean absolute slope (MAVS), integrated electromyography (IEMG), standard deviation (STD), and zero crossing number (Zero Crossing). Three frequency domain features that provide information about the signal spectrum include mean power frequency (MPF), median frequency (MF), and total power (TP). Two nonlinear eigenvalues ​​that can accurately reflect the complexity and diversity of muscle activity include sample entropy (SampEn) and fuzzy entropy (FuzzyEn).

[0106] Further description, the adaptive impedance control unit also includes: an information storage module, an information display module and a neural network construction module; the information storage module is connected to the signal detection module, and is used to store pressure signals and angle signals; the information display module is connected to the signal detection module, and is used to display pressure signals and angle signals; the neural network construction module is connected to the signal detection module and the electromyographic signal processing module, and is used to construct an initial neural network model based on multiple eigenvalues, and obtain a neural network model by training the initial neural network model through electromyographic signals and angle signals and verifying the accuracy of the initial neural network model.

[0107] In addition, the myoelectrically controlled ankle rehabilitation system also includes: a wireless transmission module, a single-chip microcomputer and a motor driver;

[0108] The wireless transmission module is connected to the single chip microcomputer and is used for transmitting the control signal of the adaptive impedance control unit to the single chip microcomputer.

[0109] The single chip microcomputer is respectively connected to motor driver 1, motor driver 2, motor driver 3 and motor driver 4, and is used to generate motor control instructions and send them to the corresponding motor drivers when receiving the control signal of the adaptive impedance control component. Motor driver 1 drives the dorsiflexion motor 500, motor driver 2 drives the plantar flexion motor 600, motor driver 3 drives the inversion / valgus motor 800 and motor driver 4 drives the abduction / adduction motor 700. The dorsiflexion motor 500 and the plantar flexion motor 600 work together to drive the flexible ankle rehabilitation exoskeleton to complete the ankle dorsiflexion / plantar flexion movement, the inversion / valgus motor 800 works to drive the flexible ankle rehabilitation exoskeleton to complete the ankle inversion / valgus movement, and the abduction / adduction motor 700 works to drive the flexible ankle rehabilitation exoskeleton to complete the ankle abduction / adduction movement.

[0110] In summary, the flexible ankle rehabilitation exoskeleton of the present invention adopts an exoskeleton wearable design, and is connected by three carbon fiber plates as support, making the exoskeleton more comfortable to wear. The carbon fiber plates have the characteristics of high strength and rigidity, which can ensure that the dorsiflexion motor 500, the plantar flexion motor 600, the abduction / adduction motor 700 and the inversion / valgus motor 800 drive the footrest 100 to rotate while ensuring that specific degrees of freedom move while other degrees of freedom do not move. The adaptive impedance control unit of the present invention adopts a technical solution to adaptively adjust the impedance of the flexible ankle rehabilitation exoskeleton based on the active movement intention and passive movement information of the human body, so as to achieve seamless docking of active excitation and interactive assistance of the flexible ankle rehabilitation exoskeleton, so that the patient's ankle joint can be actively trained and passively trained.

[0111] In the description of the present invention, it should be understood that the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0112] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0113] In the present invention, unless otherwise clearly specified and limited, when a first feature is “on” or “below” a second feature, it may be that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediate medium. Moreover, when a first feature is “above”, “above” or “above” a second feature, it may be that the first feature is directly above or obliquely above the second feature, or it may simply mean that the first feature is higher in level than the second feature. When a first feature is “below”, “below” or “below” a second feature, it may be that the first feature is directly below or obliquely below the second feature, or it may simply mean that the first feature is lower in level than the second feature.

[0114] In the description of this specification, the description of the terms "one embodiment", "some embodiments", "embodiment", "example", "specific example" or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, unless they are contradictory.

[0115] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present invention. A person skilled in the art may alter, modify, replace and modify the above embodiments within the scope of the present invention.

Claims

1. A myoelectrically controlled ankle joint rehabilitation system, characterized in that: include: Flexible ankle rehabilitation exoskeleton and adaptive impedance control components; The flexible ankle joint rehabilitation exoskeleton includes: a footrest, an upper fixing component, an intermediate supporting component, a transmission component, a dorsiflexion motor, a plantar flexion motor, an abduction / adduction motor, and an inversion / eversion motor; The footrest and the upper fixing assembly are used to fix and support the lower limbs of the human body; The middle support component is connected to the footrest and the upper fixing component respectively, and a carbon fiber plate is provided on the middle support component to enable the flexible ankle joint rehabilitation exoskeleton to complete three-degree-of-freedom movement; The dorsiflexion motor, plantar flexion motor and inversion / eversion motor are all arranged in the upper fixed assembly and connected to the footrest through the driving rope in the transmission assembly, and are used to drive the ankle joint to perform one of dorsiflexion, plantar flexion, inversion and eversion when the driving rope is retracted or released; The abduction / adduction motor is arranged in the middle support assembly and connected to the footrest through a connecting shaft in the transmission assembly, so as to drive the ankle joint to perform abduction or adduction movement when the connecting shaft rotates; The adaptive impedance control component is used to control the movement of the flexible ankle joint rehabilitation exoskeleton by acquiring the human body's active movement intention constructed by the electromyographic signal of the calf muscle, and adaptively adjust the impedance of the flexible ankle joint rehabilitation exoskeleton in combination with the human body's passive movement information.

2. The myoelectrically controlled ankle joint rehabilitation system according to claim 1, characterized in that: The upper fixing assembly includes: a front fixing plate, a rear fixing plate, a first motor mounting plate, a second motor mounting plate, an inward / outward motor support plate, a first transmission plate, a second transmission plate, a third transmission plate, and a fourth transmission plate; The front fixing plate and the rear fixing plate are connected by elastic straps on the strap holes, and are used to fix and support the lower legs of the human body; A first transmission plate and a second transmission plate are arranged on both sides of the first motor mounting plate and connected to the front fixing plate, and the dorsiflexion motor is mounted on the first motor mounting plate; A third transmission plate and a fourth transmission plate are arranged on both sides of the second motor mounting plate and are connected to the rear fixing plate, the plantar flexion motor is mounted on the second motor mounting plate, and the varus / valgus motor is mounted on the second motor mounting plate through two varus / valgus motor support plates; The first transmission plate, the second transmission plate, the third transmission plate and the fourth transmission plate are all riveted with bearings.

3. The myoelectrically controlled ankle joint rehabilitation system according to claim 2, characterized in that: The transmission assembly includes: a first drive rope, a second drive rope, a third drive rope, a fourth drive rope, a first wire wheel, a second wire wheel, a third wire wheel, a fourth wire wheel, a first drive rod, a second drive rod and a connecting shaft; One end of the first driving rope is connected to the first connecting hole of the foot support, and the other end of the first driving rope is connected to the first wire wheel arranged on the rotating shaft of the dorsiflexion motor; One end of the second driving rope is connected to the second connecting hole of the foot support, and the other end of the second driving rope is connected to the second wire wheel arranged on the rotating shaft of the plantar flexion motor; The first driving rod sequentially passes through the bearing on the first transmission plate, the third wire wheel, the bearing on the third transmission plate and the left rotating shaft of the inversion / outversion motor to engage with the gears, and the third wire wheel is connected to the third connecting hole of the foot support through the third driving rope; The second driving rod sequentially passes through the bearing on the second transmission plate, the fourth wire wheel, the bearing on the fourth transmission plate and the right rotating shaft of the inversion / outversion motor to engage with the gears, and the fourth wire wheel is connected to the fourth connecting hole of the foot support through the fourth driving rope; One end of the connecting shaft is connected with the rotating shaft of the abduction / adduction motor by transition fit and is locked by a fastening screw, and the other end is fixedly connected with the foot support. The first driving rod and the second driving rod rotate in opposite directions under the drive of the inward / outward turning motor.

4. The myoelectrically controlled ankle joint rehabilitation system according to claim 1, characterized in that: The middle support assembly includes: a first lower support plate, a second lower support plate, a third lower support plate, a first carbon fiber plate, a second carbon fiber plate, a third carbon fiber plate, a first upper support plate, a second upper support plate and a third upper support plate; The first lower support plate is arranged on the left side of the footrest, the first lower support plate is staggeredly connected with the first upper support plate through the first carbon fiber plate, and the first upper support plate is also movably connected with the upper fixing assembly through the waist-shaped hole; The second lower support plate is arranged on the right side of the footrest, the second lower support plate is staggeredly connected with the second upper support plate through the second carbon fiber plate, and the second upper support plate is also movably connected with the upper fixing assembly through the waist-shaped hole; The third lower support plate is provided with an extension / retraction motor. The third lower support plate is staggeredly connected to the third upper support plate through a third carbon fiber plate. The third upper support plate is also connected to the upper fixing assembly.

5. The myoelectrically controlled ankle joint rehabilitation system according to claim 1, characterized in that: include: Wireless transmission module, single chip microcomputer and motor driver; The wireless transmission module is connected to the single chip microcomputer and is used to transmit the control signal of the adaptive impedance control unit to the single chip microcomputer; The single-chip microcomputer is connected to the motor driver and is used to generate a motor control instruction and send it to the motor driver when receiving the control signal of the adaptive impedance control component. The motor driver drives the dorsiflexion motor, plantar flexion motor, inversion / eversion motor and abduction / adduction motor to rotate to drive the flexible ankle joint rehabilitation exoskeleton to complete the ankle joint dorsiflexion / plantar flexion movement, inversion / eversion movement and abduction / adduction movement.

6. The myoelectrically controlled ankle joint rehabilitation system according to claim 1, characterized in that: The adaptive impedance control component includes: a signal detection module, an electromyographic signal processing module, an ankle joint angle prediction module, a motor control module and an adaptive impedance adjustment module; The signal detection module is used to collect the electromyographic signals of the calf muscles and the passive motion information of the human body; The electromyographic signal processing module is connected to the signal detection module and is used to pre-process and extract features of the electromyographic signal to obtain multiple feature values ​​of the electromyographic signal; The ankle joint angle prediction module is connected to the electromyographic signal processing module and is used to input multiple characteristic values ​​into a pre-trained neural network model to predict the ankle joint angle and obtain the ankle joint angle prediction result; The motor control module and the ankle joint angle prediction module are used to convert the human active movement intention constructed based on the ankle joint angle prediction result into the robot movement model to obtain the motor control signal; The adaptive impedance adjustment module is connected to the motor control module and the signal detection module respectively, and is used to adjust the inertia, stiffness and damping model parameters of the flexible ankle joint rehabilitation exoskeleton in real time based on the human body's active movement intention and the human body's passive movement information.

7. The myoelectrically controlled ankle joint rehabilitation system according to claim 6, characterized in that: The information detection unit includes: a fabric electrode, a pressure sensor, an acceleration sensor and an angular displacement sensor; The fabric electrodes can be adjusted according to the wearer's calf muscle distribution information to collect the electromyographic signals of the tibialis anterior, gastrocnemius, gastrocnemius lateralis, peroneus longus and soleus muscles; The pressure sensor is used to collect the pressure signal of footsteps; The acceleration sensor is used to collect the acceleration signal of the ankle; The angular displacement sensor is used to collect the angle signal of the ankle.

8. The myoelectrically controlled ankle joint rehabilitation system according to claim 6, characterized in that: The electromyographic signal processing module includes: an empirical mode decomposition unit, a noise reduction unit, an electromyographic signal reconstruction unit and a feature extraction unit which are connected in sequence; The empirical mode decomposition unit is used to decompose the electromyographic signal based on the empirical mode decomposition algorithm to obtain multiple intrinsic mode functions; The noise reduction unit is used to remove noise and interference in each intrinsic mode function based on a soft threshold algorithm; The electromyographic signal reconstruction unit is used to reconstruct the intrinsic mode function after removing noise and interference to obtain the electromyographic signal after noise reduction; The feature extraction unit is used to perform time domain, frequency domain and nonlinear analysis on the denoised electromyographic signal to obtain a plurality of time domain eigenvalues, a plurality of frequency domain eigenvalues ​​and a plurality of nonlinear eigenvalues.

9. The myoelectrically controlled ankle joint rehabilitation system according to claim 8, characterized in that: The method steps of the denoising unit for denoising the intrinsic mode function include: Compare the coefficient of each eigenmode function with the set threshold; If the comparison result shows that the coefficient of the intrinsic mode function is less than the set threshold, the coefficient of the intrinsic mode function is modified to 0; If the comparison result shows that the coefficient of the intrinsic mode function is not less than the set threshold, the coefficient of the intrinsic mode function is retained.

10. The myoelectrically controlled ankle joint rehabilitation system according to claim 7, characterized in that: The adaptive impedance control unit also includes: an information storage module, an information display module and a neural network construction module; The information storage module is connected to the signal detection module and is used to store the pressure signal and the angle signal; The information display module is connected to the signal detection module and is used to display the pressure signal and the angle signal; The neural network construction module is connected with the signal detection module and the electromyographic signal processing module, and is used to construct an initial neural network model based on multiple eigenvalues, and to obtain a neural network model by training the initial neural network model through electromyographic signals and angle signals and verifying the accuracy of the initial neural network model.

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