A knee joint rehabilitation training-oriented auxiliary system and method

Abstract

The application relates to a knee joint rehabilitation training auxiliary system and method, which comprises a central control module connected with a surface electromyogram sensor, a man-machine interaction interface and a mechanical driving module; an angle encoder is connected with the man-machine interaction interface; the surface electromyogram sensor is used for acquiring the surface electromyogram of the user's leg in real time; the angle encoder is used for acquiring the actual joint bending angle of the user in real time; the man-machine interaction interface is used for acquiring the training mode information, training time and ideal joint bending angle input by the user, and displaying the actual joint bending angle of the user; the training mode information comprises an active training mode or a passive training mode; the central control module is used for calculating a motor speed signal according to the training mode information, training time, actual joint bending angle of the user, surface electromyogram of the user's leg and ideal joint bending angle input by the user; and the mechanical driving module is used for assisting the user in rehabilitation training according to the motor speed signal, so that the knee joint rehabilitation training of the user can be assisted.

Description

Technical Field

[0001] This invention belongs to the field of rehabilitation training technology, specifically relating to an auxiliary system and method for knee joint rehabilitation training. Background Technology

[0002] The demand for elderly care, disability assistance, rehabilitation, and sports rehabilitation is increasing rapidly in the future. Intelligent rehabilitation assistive systems, characterized by bio-mechanical-electrical integration, combine knowledge from biomedicine, information science, mechanics, electronics, and automatic control to solve technological challenges such as human movement intention recognition and intelligent interactive control methods. This can effectively promote technological progress and conceptual change in rehabilitation medicine and mechatronics, providing theoretical and technical support for the prevention and treatment of age-related diseases, and contributing to healthy aging and healthy growth.

[0003] The knee joint is a vital part of the human body, bearing the majority of the body's weight during daily activities such as walking. It plays a crucial role in daily life and is frequently injured during exercise. Furthermore, the recovery of knee function after total knee replacement surgery requires specific rehabilitation training. Therefore, this patent designs an intelligent wearable rehabilitation training aid for knee joint rehabilitation, enabling both active and passive rehabilitation training.

[0004] Current situation: At present, there are some assistive devices available both domestically and internationally to help patients complete knee joint rehabilitation training, such as rehabilitation robots, rehabilitation exercise machines, backrest-type knee joint exercise machines, rehabilitation activity therapy devices, and wearable knee joint physiotherapy devices.

[0005] Common lower limb rehabilitation robots, through body posture information acquisition and mechanical control modules, can intelligently assist patients in completing professional active and passive rehabilitation training simultaneously targeting major lower limb joints such as the knee, hip, and ankle. They are powerful and can realistically simulate the process of daily walking. However, these devices are bulky, expensive, and require the assistance of professional therapists, typically targeting hospitals and rehabilitation centers, thus limiting their accessibility to a wider consumer base.

[0006] To reduce the cost and complexity of equipment, assistive devices specifically designed for knee joint rehabilitation training have emerged on the market, such as rehabilitation exercise machines, backrest-type knee joint exercisers, and rehabilitation activity therapy devices. These devices target only the movement of a single joint, thus their mechanical structures are typically simpler, and their costs are relatively lower. However, these rehabilitation devices require a base or device for fixation during use, making them inconvenient to move and generally only suitable for hospitals or physiotherapy centers. Furthermore, this type of device currently only enables simple active rehabilitation training modes and lacks intelligent interactive control.

[0007] Recently, wearable knee rehabilitation training devices have emerged. These devices wrap around the outside of the thigh and calf, using a motor at the joint to provide torque for knee flexion. They are convenient to use without the need for a fixed base or device, and their applications are more diverse. However, to drive knee flexion, these devices need to provide a very large torque at the knee joint, resulting in high motor power, large size, and high cost. In addition, the related mechanical structure is complex to achieve deceleration and torque increase, causing many inconveniences during use. Summary of the Invention

[0008] This invention relates to an auxiliary system and method for knee joint rehabilitation training, aiming to provide patients who need knee joint rehabilitation with a system that is cheaper and easier to use than rehabilitation robots, can provide greater assistance to the knee joint, and has active and passive rehabilitation training modes.

[0009] One aspect of the present invention provides an auxiliary system for knee joint rehabilitation training, specifically including: a surface electromyography signal sensor, a human-computer interaction interface, an angle encoder, a central control module, and a mechanical drive module;

[0010] The central control module is connected to the surface electromyography signal sensor, the human-machine interface, and the mechanical drive module, respectively; the angle encoder is connected to the human-machine interface.

[0011] The surface electromyography (EMG) sensor is used to acquire surface EMG signals of the user's legs in real time.

[0012] The angle encoder is used to obtain the user's actual joint bending angle in real time.

[0013] The human-computer interaction interface is used to obtain training mode information, training time and ideal joint bending angle input by the user, and to display the user's actual joint bending angle; the training mode information includes: active training mode or passive training mode.

[0014] The central control module is used to calculate the motor speed control signal based on the training mode information, training time, actual joint bending angle of the user, surface electromyography signal of the user's leg, and ideal joint bending angle input by the user.

[0015] The mechanical drive module is used to assist users in rehabilitation training based on motor speed control signals.

[0016] Furthermore, the central control module includes: a knee flexion movement intention calculation unit, a knee flexion movement control algorithm unit, and a motor speed control unit;

[0017] The knee flexion movement intention calculation unit is used to calculate the user's knee flexion movement intention based on surface electromyography signals;

[0018] The knee flexion motion control algorithm unit is used to control the user's actual knee flexion motion intention during the training time based on the training mode information input by the user and the user's knee flexion motion intention.

[0019] The motor speed control unit is used to calculate the motor speed control signal based on the user's actual knee flexion movement intention, the user's actual joint flexion angle, and the user's input ideal joint flexion angle.

[0020] Furthermore, the step of calculating the user's knee flexion movement intention based on surface electromyography signals includes:

[0021] K = envelope(sEMG)

[0022] Wherein, sEMG represents surface electromyography signal, K represents the intention of knee flexion movement, and envelope represents the signal envelope function.

[0023] Furthermore, the control of the user's actual knee flexion movement intention includes:

[0024]

[0025] Among them, K true This indicates the user's true intention to flex their knee.

[0026] Furthermore, the motor speed control signal includes:

[0027]

[0028] Where F represents the motor speed control signal, the larger the value, the higher the output speed of the motor, and the positive and negative signs represent the direction of the motor speed; θ1 represents the actual joint bending angle of the user; θ0 represents the ideal joint bending angle input by the user; V0 represents the rated speed of the motor; W represents the mechanical structure deceleration torque increase parameter, and its value ranges from 1 to 50 depending on the actual deceleration mechanical structure selected.

[0029] Furthermore, the mechanical drive module includes a thigh support mechanism and a calf support mechanism; the thigh support mechanism and the calf support mechanism are hinged together by an angle encoder. The thigh support mechanism includes a threaded rod, a thigh placement pad, and brushless motors disposed on both sides of the thigh placement pad. One end of the thigh placement pad is provided with a thigh retractable hinge bracket. The calf support mechanism includes a calf support pad and ball screws disposed on both sides of the calf support pad. One end of the calf support pad is provided with a calf retractable hinge bracket. One end of the threaded rod is hinged to the brushless motor through a gear, and the other end of the threaded rod passes through the ball screw and is threadedly engaged with the ball screw. The thigh retractable hinge bracket and the calf retractable hinge bracket are slidably connected to both sides of the angle encoder, and the brushless motor is connected to the central control module.

[0030] Furthermore, the thigh pad and calf support pad are provided with multiple through holes running vertically through the thigh and calf.

[0031] Furthermore, the surfaces of both the thigh pad and the calf support pad are concave curved surfaces.

[0032] Furthermore, the surfaces of the thigh pad and calf support pad are provided with sponge and a synthetic fiber fabric outside the sponge.

[0033] Furthermore, the thigh pad and the calf support pad are each provided with multiple straps.

[0034] Another aspect of the present invention provides an assistive method for knee joint rehabilitation training, the method being applied to the aforementioned assistive system for knee joint rehabilitation training, comprising:

[0035] S1: Obtain the training mode information, training time, and ideal joint bending angle input by the user; the training mode information includes: active training mode or passive training mode;

[0036] S2: Real-time acquisition of surface electromyography (EMG) signals from the user's legs using a surface EMG signal sensor;

[0037] S3: Uses an angle encoder to obtain the actual joint bending angle of the user's leg in real time;

[0038] S4: Determine the user's knee flexion intention based on surface electromyography signals;

[0039] K = envelope(sEMG)

[0040] Wherein, sEMG represents surface electromyography signal, K represents the intention of knee flexion movement, and envelope represents the signal envelope function.

[0041] S5: Based on the training mode information input by the user and the user's knee flexion movement intention, control the user's actual knee flexion movement intention during the training time.

[0042]

[0043] Among them, K true This indicates the user's true intention to flex their knee.

[0044] S6: Calculate the motor speed control signal based on the user's actual knee flexion movement intention, the user's actual joint flexion angle, and the user's input ideal joint flexion angle;

[0045] S7: Drives the mechanical drive module according to the motor speed control signal to assist the user in knee joint rehabilitation training.

[0046] The present invention has at least the following beneficial effects

[0047] The device is designed as a wearable device, making it convenient to use and expanding its application scenarios. It achieves intelligent interaction between the patient and the device in both active and passive rehabilitation training modes through bio-mechanical-electrical integration technology. The innovative mechanical structure enhances the device's assistive effect on the patient's knee joint. It provides selectable active and passive rehabilitation training modes for knee joint rehabilitation. Furthermore, the device uses a brushless motor to drive knee joint rotation, which is cheaper than the stepper motors used in rehabilitation robots. The ball screw used in this invention has a unidirectional power transmission characteristic, meaning that power can only be transmitted from the brushless motor to the lower leg support, and not vice versa. This allows for mechanical self-locking of the knee joint angle even when the brushless motor is not powered, saving power consumption. Attached Figure Description

[0048] Figure 1 This is a system block diagram of the present invention;

[0049] Figure 2 This is a schematic diagram of the mechanical control module of the present invention;

[0050] Among them, 1. Thigh support mechanism, 2. Lower leg support mechanism, 3. Angle encoder, 11. Thigh placement pad, 12. Brushless motor, 13. Thigh telescopic hinge bracket, 14. Threaded rod, 21. Lower leg support pad, 22. Ball screw, 23. Lower leg telescopic hinge bracket. Detailed Implementation

[0051] The following specific examples illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the illustrations provided in the following embodiments are only schematic representations of the basic concept of the present invention. Unless otherwise specified, the following embodiments and features can be combined with each other.

[0052] The accompanying drawings are for illustrative purposes only and are schematic diagrams, not actual pictures. They should not be construed as limiting the invention. To better illustrate the embodiments of the invention, some parts in the drawings may be omitted, enlarged, or reduced, and do not represent the actual product dimensions. It is understandable to those skilled in the art that some well-known structures and their descriptions may be omitted in the drawings.

[0053] In the accompanying drawings of the embodiments of the present invention, the same or similar reference numerals correspond to the same or similar components. In the description of the present invention, it should be understood that if terms such as "upper," "lower," "left," "right," "front," and "rear" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, they are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, the terms used to describe positional relationships in the drawings are only for illustrative purposes and should not be construed as limiting the present invention. For those skilled in the art, the specific meaning of the above terms can be understood according to the specific circumstances.

[0054] Please see Figure 1 One aspect of the present invention provides an auxiliary system for knee joint rehabilitation training, comprising: a surface electromyography (sEMG) sensor, a human-computer interaction interface, an angle encoder 3, a central control module, and a mechanical drive module.

[0055] The surface electromyography (EMG) sensor is used to acquire surface EMG signals of the user's legs in real time.

[0056] The angle encoder 3 is used to acquire the user's actual joint bending angle in real time.

[0057] The human-computer interaction interface is used to obtain training mode information, training time and ideal joint bending angle input by the user, and to display the user's actual joint bending angle; the training mode information includes: active training mode or passive training mode.

[0058] The central control module is used to calculate the motor speed control signal based on the training mode information, training time, actual joint bending angle of the user, surface electromyography signal of the user's leg, and ideal joint bending angle input by the user.

[0059] The mechanical drive module is used to assist users in rehabilitation training based on motor speed control signals.

[0060] The central control module can be implemented based on STM32 and Arduino controllers, or electronic components can be selected and assembled through PCB design to realize the functions required by the electronic control part of this invention.

[0061] Human-computer interaction interfaces can take many forms, such as remote control handles, display control interfaces, etc. The central control module and the human-computer interaction interface can communicate through wired or wireless means.

[0062] The human-computer interaction interface is used to receive rehabilitation training instructions input by users (including patients, doctors, physiotherapists, etc.). The interface includes a physical display screen and physical buttons, prompting users to input rehabilitation training plans (including training mode, number of training sessions, total training time, duration of a single cycle, etc.), and feeding back information from the device during the training process to the user through the display screen or voice prompts.

[0063] Furthermore, the central control module includes: a knee flexion movement intention calculation unit, a knee flexion movement control algorithm unit, and a motor speed control unit;

[0064] The knee flexion movement intention calculation unit is used to calculate the user's knee flexion movement intention based on surface electromyography signals;

[0065] The knee flexion motion control algorithm unit is used to control the user's actual knee flexion motion intention during the training time based on the training mode information input by the user and the user's knee flexion motion intention.

[0066] The motor speed control unit is used to calculate the motor speed control signal based on the user's actual knee flexion movement intention, the user's actual joint flexion angle, and the user's input ideal joint flexion angle.

[0067] Furthermore, the step of calculating the user's knee flexion movement intention based on surface electromyography signals includes:

[0068] K = envelope(sEMG)

[0069] Wherein, sEMG represents surface electromyography signal, K represents the intention of knee flexion movement, and envelope represents the signal envelope function.

[0070] Furthermore, the control of the user's actual knee flexion movement intention includes:

[0071]

[0072] Among them, K true This indicates the user's true intention to flex their knee.

[0073] Furthermore, the motor speed control signal includes:

[0074]

[0075] Where F represents the motor speed control signal, the larger the value, the higher the output speed of the motor, and the positive and negative signs represent the direction of the motor speed; θ1 represents the actual joint bending angle of the user; θ0 represents the ideal joint bending angle input by the user; V0 represents the rated speed of the motor; W represents the mechanical structure deceleration torque increase parameter, and its value ranges from 1 to 50 depending on the actual deceleration mechanical structure selected.

[0076] Please see Figure 2 Furthermore, the mechanical drive module includes: a thigh support mechanism 1 and a calf support mechanism 2; the thigh support mechanism 1 and the calf support mechanism 2 are hinged together by an angle encoder 3. The thigh support mechanism 1 includes: a threaded rod 14, a thigh placement pad 11, and brushless motors 12 disposed on both sides of the thigh placement pad 11. One end of the thigh placement pad 11 is provided with a thigh retractable hinge bracket 13. The calf support mechanism 2 includes: a calf support pad 21 and ball screws 22 disposed on both sides of the calf support pad 21. One end of the calf support pad 21 is provided with a calf retractable hinge bracket 23. One end of the threaded rod 14 is hinged to the brushless motor 12 through a gear, and the other end of the threaded rod 14 passes through the ball screw 22 and is threadedly engaged with the ball screw 22. The thigh retractable hinge bracket 13 and the calf retractable hinge bracket 23 are slidably connected to both sides of the angle encoder 3, and the brushless motor 12 is connected to the central control module.

[0077] Through specific mechanical structure design, it has the physical function of limiting the rotation angle of the knee joint, with a rotation range of 1° to -101°.

[0078] Furthermore, the thigh pad 11 and calf support pad 21 are provided with multiple through holes running vertically through the body. Providing through holes in the thigh pad 11 and calf support pad 21 makes the user more comfortable during exercise, as the increased number of through holes allows for better breathability.

[0079] Furthermore, the surfaces of both the thigh support pad 11 and the calf support pad 21 are concave curved surfaces. The concave curved surfaces can better conform to the shape of the user's legs, making it easier to fix the user's legs.

[0080] Furthermore, the surfaces of the thigh support pad 11 and the calf support pad 21 are provided with sponge and a synthetic fiber fabric covering the sponge. The sponge construction makes the surface softer and more comfortable to the user, enhancing the user experience.

[0081] Furthermore, the thigh placement pad 11 and the calf support pad 21 are each equipped with multiple straps. By setting multiple straps to fix the user's thigh and calf to the thigh placement pad 11 and the calf support pad 21 respectively, the safety during rehabilitation training is improved.

[0082] Another aspect of the present invention provides an assistive method for knee joint rehabilitation training, the method being applied to an assistive system for knee joint rehabilitation training, comprising:

[0083] S1: Obtain the training mode information, training time, and ideal joint bending angle input by the user; the training mode information includes: active training mode or passive training mode;

[0084] S2: Real-time acquisition of surface electromyography (EMG) signals from the user's legs using a surface EMG signal sensor;

[0085] S3: Uses an angle encoder to obtain the actual joint bending angle of the user's leg in real time;

[0086] S4: Determine the user's knee flexion intention based on surface electromyography signals;

[0087] K = envelope(sEMG)

[0088] Wherein, sEMG represents surface electromyography signal, K represents the intention of knee flexion movement, and envelope represents the signal envelope function.

[0089] S5: Based on the training mode information input by the user and the user's knee flexion movement intention, control the user's actual knee flexion movement intention during the training time.

[0090]

[0091] Among them, K true This indicates the user's true intention to flex their knee.

[0092] S6: Calculate the motor speed control signal based on the user's actual knee flexion movement intention, the user's actual joint flexion angle, and the user's input ideal joint flexion angle;

[0093] S7: Drives the mechanical drive module according to the motor speed control signal to assist the user in knee joint rehabilitation training.

[0094] In this invention, the assistive system for knee joint rehabilitation training requires the user to input the training mode, ideal knee flexion angle, number of training sessions, training cycle, and training time through a human-computer interaction interface. The central control module then drives the drive module to move according to the user's input training mode, thereby achieving knee joint rehabilitation training. Specifically, the system calculates the user's knee flexion movement intention by judging the user's input training mode and the surface electromyography (EMG) signals collected by the surface EMG sensor. Based on the user's knee flexion movement intention, the user's actual joint flexion angle, and the user's input ideal joint flexion angle, the system calculates the motor speed control signal to control the mechanical control module.

[0095] The device is designed as a wearable device, making it convenient to use and expanding its application scenarios. It achieves intelligent interaction between the patient and the device in both active and passive rehabilitation training modes through bio-mechanical-electrical integration technology. The innovative mechanical structure enhances the device's assistive effect on the patient's knee joint. It provides selectable active and passive rehabilitation training modes for knee joint rehabilitation. The device uses a thigh placement pad 11 to drive knee joint rotation, which is cheaper than the stepper motor used in rehabilitation robots. The ball screw 22 used in this invention has a unidirectional power transmission characteristic, meaning that power can only be transmitted from the thigh placement pad 11 to the calf support, and not vice versa. This allows for mechanical self-locking of the knee joint angle even when the thigh placement pad 11 is not powered, saving power consumption.

[0096] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A knee joint rehabilitation training oriented auxiliary system, characterized in that, include: Surface electromyography signal sensor, human-machine interface, angle encoder (3), central control module, mechanical drive module; The central control module is connected to the surface electromyography signal sensor, the human-machine interface and the mechanical drive module respectively; the angle encoder (3) is connected to the human-machine interface; The surface electromyography (EMG) sensor is used to acquire surface EMG signals of the user's legs in real time. The angle encoder (3) is used to obtain the user's actual joint bending angle in real time; The human-computer interaction interface is used to obtain training mode information, training time and ideal joint bending angle input by the user, and to display the user's actual joint bending angle. The training mode information includes: active training mode or passive training mode; The central control module is used to calculate the motor speed control signal based on the training mode information, training time, actual joint bending angle of the user, surface electromyography signal of the user's leg, and ideal joint bending angle input by the user. The mechanical drive module is used to assist the user in rehabilitation training based on the motor speed control signal. The central control module includes: a knee flexion movement intention calculation unit, a knee flexion movement control algorithm unit, and a motor speed control unit; The knee flexion movement intention calculation unit is used to calculate the user's knee flexion movement intention based on surface electromyography signals; The knee flexion motion control algorithm unit is used to control the user's actual knee flexion motion intention during the training time based on the training mode information input by the user and the user's knee flexion motion intention. The motor speed control unit is used to calculate the motor speed control signal based on the user's actual knee flexion movement intention, the user's actual joint flexion angle, and the user's input ideal joint flexion angle. The process of calculating the user's knee flexion movement intention based on surface electromyography signals includes: in, This represents surface electromyography (EMG) signals, where K represents the intention to flex the knee joint. Represents the signal envelope function; The control of the user's actual knee flexion movement intentions includes: in, This indicates the user's true intention to flex their knee. The motor speed control signal includes: in, This indicates the motor speed control signal; This indicates the user's actual joint bending angle; This represents the ideal joint bending angle input by the user; Indicates the rated speed of the motor. This represents the deceleration and torque amplification parameters of the mechanical structure.

2. The assistive system for knee joint rehabilitation training according to claim 1, characterized in that, The mechanical drive module includes: a thigh support mechanism (1) and a calf support mechanism (2); the thigh support mechanism (1) and the calf support mechanism (2) are hinged by an angle encoder (3). The thigh support mechanism (1) includes: a threaded rod (14), a thigh placement pad (11), and brushless motors (12) arranged on both sides of the thigh placement pad (11). One end of the thigh placement pad (11) is provided with a thigh telescopic hinge bracket (13). The calf support mechanism (2) includes: a calf support pad (21) and a... Ball screws (22) are located on both sides of the calf support pad (21); a calf telescopic hinge bracket (23) is provided at one end of the calf support pad (21); one end of the threaded rod (14) is hinged to the brushless motor (12) through a gear; the other end of the threaded rod (14) passes through the ball screw (22) and is threadedly engaged with the ball screw (22); the thigh telescopic hinge bracket (13) and the calf telescopic hinge bracket (23) are slidably connected to both sides of the angle encoder (3); the brushless motor (12) is connected to the central control module.

3. The assistive system for knee joint rehabilitation training according to claim 2, characterized in that, The thigh pad (11) and calf support pad (21) are provided with multiple through holes running vertically through the thigh.

4. The assistive system for knee joint rehabilitation training according to claim 2, characterized in that, The surfaces of the thigh pad (11) and the calf support pad (21) are both concave curved surfaces.

5. The assistive system for knee joint rehabilitation training according to claim 2, characterized in that, The surfaces of the thigh pad (11) and calf support pad (21) are provided with sponge and synthetic fiber fabric outside the sponge.

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