Hand exoskeleton robot based on progressive rehabilitation and method thereof

Abstract

The invention relates to a hand exoskeleton robot based on progressive rehabilitation and a method thereof, solves the problems of single rehabilitation mode, insufficient control precision, heavy structure and the like in the prior art, realizes complete-cycle rehabilitation training and provides a personalized rehabilitation scheme. A hand exoskeleton robot based on progressive rehabilitation comprises a driving module, a skeleton mechanism, a sensing module and a control module. The driving module is used for providing linear driving force; the skeleton mechanism comprises a rigid assembly and a flexible connecting structure which can move relatively, and is used for converting the linear driving force into bending movement of fingers; the sensing module comprises a first sensor used for detecting the joint angle and a second sensor used for monitoring output force. And the control module adjusts the output of the driving module through cascade closed-loop control based on feedback signals of the first sensor and the second sensor.

Description

Technical Field

[0001] This invention belongs to the field of exoskeleton rehabilitation technology, and relates to a hand exoskeleton robot based on progressive rehabilitation and its control method. Background Technology

[0002] Hands are essential tools in daily life; however, accidents, strokes, and other factors often cause hand injuries, leading to finger dysfunction and severely impacting patients' self-care abilities and quality of life. Many patients, even after receiving hand function rehabilitation treatment, may still have residual hand function deficits upon discharge, requiring ongoing rehabilitation intervention. Currently, hand rehabilitation exoskeletons can be used to train the hand for rehabilitation purposes.

[0003] Existing hand rehabilitation exoskeletons can be divided into three categories: mechanical rigid hand exoskeletons, pneumatic flexible exoskeletons, and lasso-driven flexible exoskeletons. Among them, mechanical rigid exoskeletons are complex and bulky, making them extremely inconvenient for patients with pre-existing hand function impairments to wear daily, so they are usually only used as professional rehabilitation equipment in hospitals; pneumatic flexible exoskeletons are lighter, but they have non-linear characteristics and time delays, making it difficult to achieve precise position control; as for rope / lasso-driven flexible exoskeletons, although they can provide greater tensile and bending forces, they can lead to uneven force distribution on the hand, easily causing damage to the skin and finger joints.

[0004] In addition, existing exoskeletons typically use DC brushed motors and encoders as motor drives, which can only achieve passive trajectory repetitive training, resulting in rehabilitation exercises that are not close to real-life scenarios and affecting the actual rehabilitation effect.

[0005] Therefore, there is an urgent need to develop a rehabilitation robot device with high versatility and adaptability to improve the comfort and effectiveness of rehabilitation training. Summary of the Invention

[0006] To address the aforementioned technical problems, this invention proposes a hand exoskeleton robot based on progressive rehabilitation, which solves the problems of single rehabilitation mode, insufficient control precision, and bulky structure in existing technologies, realizes full-cycle rehabilitation training, and provides personalized rehabilitation solutions.

[0007] The technical solution of the present invention to solve the above problems is: a hand exoskeleton robot based on progressive rehabilitation, which is characterized by including a drive module, a skeletal mechanism, a sensing module and a control module.

[0008] The drive module provides a linear driving force; the skeletal mechanism, including a relatively movable rigid component and a flexible connection structure, converts the linear driving force into a bending motion of the fingers; the sensing module includes a first sensor for detecting joint angles and a second sensor for monitoring output force; the control module adjusts the output of the drive module through cascade closed-loop control based on feedback signals from the first and second sensors.

[0009] Furthermore, the first sensor is a flexible bending sensor, which is attached to the inner side of the skeletal structure; the second sensor is a force sensor, which is installed at the output end of the drive module.

[0010] Furthermore, the aforementioned drive module includes a push rod motor, and the second sensor is coaxially arranged with the push rod motor; the skeletal mechanism includes a sliding binding and at least one pair of flexible plates, which achieve bending movement through a guide; the upper part of the sliding binding is provided with a guide to guide the movement direction of the flexible plates, and the lower part is provided with a binding member to fix it to the patient's finger.

[0011] The resilient plate can be made of materials that can be bent and repositioned, such as metal or carbon fiber.

[0012] Furthermore, the aforementioned resilient plate includes an outer metal plate and an inner metal plate, and the guide includes a skeletal joint; the skeletal joint is fixed to the inner metal plate, and the skeletal joint is provided with a guide groove or guide roller, which guides the movement direction of the outer metal plate; the outer metal plate and the inner metal plate are connected at their tail ends by fingertip joints.

[0013] The guide rollers can be paired rollers or paired miniature bearings to reduce contact friction, enhance the mechanical strength and structural life of the overall system, and are suitable for long-term, repeated rehabilitation training.

[0014] Furthermore, one end of the output shaft of the aforementioned push rod motor drives the outer metal plate to move, while the other end is connected to a force sensor; the flexible bending sensor is installed on the inner metal plate.

[0015] Furthermore, the aforementioned control module includes an outer loop controller and an inner loop controller, wherein: the outer loop controller generates a target displacement signal based on angle or force error; and the inner loop controller adjusts the output of the drive module based on displacement error.

[0016] Furthermore, the outer loop controller is a proportional-integral-derivative PID controller, and its input is the feedback signal from the first sensor or the second sensor; the inner loop controller is a position PID controller, and its input is the actual displacement signal of the drive module.

[0017] Furthermore, the aforementioned skeletal structure includes a metacarpal plate, which is fixed to the wrist by a binding assembly. A push rod motor and a force sensor are mounted on the metacarpal plate using motor brackets and force sensor brackets, respectively. The push rod motor is integrated into the wrist, eliminating the need for a transmission structure, thus facilitating maintenance and reducing the burden on the patient's hand.

[0018] Furthermore, the aforementioned control module supports at least three rehabilitation modes: passive mode, based on preset angle trajectory control; assist mode, based on the patient's active force signals to provide proportional assistance; and resistance mode, applying constant resistance to strengthen muscle strength.

[0019] In addition, the present invention also proposes a control method for the above-mentioned hand exoskeleton robot, which is characterized by including the following steps:

[0020] (1) The joint bending angle of the exoskeleton is detected in real time by the first sensor;

[0021] (2) The output force of the drive module is monitored in real time by the second sensor;

[0022] (3) Select control strategies based on rehabilitation models:

[0023] Passive rehabilitation mode: Based on the preset target angle and the joint bending angle fed back by the first sensor, a target displacement signal is generated through the outer ring angle controller;

[0024] Assist / Resistance Mode: Based on the target force and the output force fed back by the second sensor, a target displacement signal is generated through an outer loop force controller;

[0025] (4) Obtain the actual displacement of the drive module through the motor potentiometer, and adjust the output of the drive module through the inner loop position controller based on the deviation between the target displacement signal and the actual displacement.

[0026] (5) Repeat steps (1)-(4) to achieve closed-loop control of joint angle or output force.

[0027] Advantages of this invention:

[0028] 1) This invention supports at least three rehabilitation modes and supports the entire rehabilitation process from early postoperative muscle strength protection to later functional reconstruction, without the need to replace equipment.

[0029] 2) The overall system of the present invention is lightweight, which reduces the burden on the patient's hands.

[0030] 3) The motor of this invention is integrated into the wrist, without a transmission structure, which facilitates maintenance.

[0031] 4) The sliding binding of the present invention can be adjusted according to the finger size of different patients, thereby improving the adaptability of the device and the personalized rehabilitation effect.

[0032] 5) The flexible bending sensor of the present invention and the motor potentiometer form a closed-loop control, avoiding trajectory deviation caused by traditional rigid transmission.

[0033] 6) This invention uses rollers to reduce contact friction, thereby enhancing the overall mechanical strength and structural lifespan of the system, making it suitable for long-term, repeated rehabilitation training.

[0034] 7) The force sensor data and joint angle signal of the present invention are fused to monitor the finger joint position and motor output load in real time, preventing excessive tendon traction caused by overload.

[0035] 8) The force sensor installed in this invention can analyze the patient's intention to exert force through micro-force signals, thereby realizing resistance training and assisted grasping.

[0036] 9) The present invention has a simple structure and relatively low manufacturing cost, which can effectively reduce the economic burden on patients. Attached Figure Description

[0037] Figure 1 A schematic diagram illustrating the wearing of the hand exoskeleton robot based on progressive rehabilitation provided by this invention;

[0038] Figure 2 This is a structural diagram of a metal skeleton assembly;

[0039] Figure 3 This is a schematic diagram of the motor drive assembly structure;

[0040] Figure 4 The diagram shows the cascade closed-loop control of the exoskeleton's bending angle.

[0041] Figure 5 This is a cascade closed-loop control diagram for the motor output force.

[0042] Among them, 1-bone joint, 2-outer metal plate, 3-flexible bending sensor, 4-sliding binding, 5-finger joint, 6-inner metal plate, 7-motor bracket, 8-adapter nut, 9-force sensor, 10-force sensing bracket, 11-push rod motor, 12-metacarpal plate, 13-roller. Detailed Implementation

[0043] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention. Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention.

[0044] This invention proposes a hand exoskeleton robot based on progressive rehabilitation, comprising a drive module, a skeleton mechanism, a sensing module, and a control module. The drive module provides linear driving force; the skeleton mechanism includes relatively movable rigid components and flexible connection structures for converting the linear driving force into finger flexion movements; the sensing module includes a first sensor for detecting joint angles and a second sensor for monitoring output force; the control module, based on feedback signals from the first and second sensors, adjusts the output of the drive module through cascaded closed-loop control.

[0045] As a preferred embodiment of the present invention, see [link to previous document]. Figure 1 The first sensor is a flexible bending sensor 3, which is attached to the inner side of the skeletal structure; the second sensor is a force sensor 9, which is installed at the output end of the drive module.

[0046] As a preferred embodiment of the present invention, see [link to previous document]. Figure 1 and Figure 3 The drive module includes a push rod motor 11, and the second sensor is coaxially arranged with the push rod motor 11; the skeletal mechanism includes a sliding restraint 4 and at least one pair of flexible plates, which achieve bending movement through guides; see also Figure 1 and Figure 2 The sliding binding 4 has a guide at the top to guide the movement of the flexible plate, and a binding at the bottom to fix it to the patient's finger. The guide is a guide groove or a pair of guide rollers, through which the flexible plate passes. A motor potentiometer is installed on the push rod motor 11 to monitor the position of the motor output shaft in real time.

[0047] The resilient plate can be made of materials that can be bent and reset, such as metal or carbon fiber.

[0048] Specifically, see Figure 1The aforementioned skeletal structure includes a metacarpal plate 12, which is fixed to the wrist by a binding assembly. A push rod motor 11 and a force sensor 9 are respectively mounted on the metacarpal plate 12 using a motor bracket 7 and a force sensor bracket 10. The push rod motor 11 is integrated into the wrist, without a transmission structure, which facilitates maintenance and reduces the burden on the patient's hand.

[0049] Specifically, see Figure 1 and Figure 3 The aforementioned resilient plate includes an outer metal plate 2 and an inner metal plate 6, and the guide includes a skeletal joint 1; the skeletal joint 1 is fixed on the inner metal plate 6, and the skeletal joint 1 is provided with a guide groove or guide roller, which guides the movement direction of the outer metal plate 2; the outer metal plate 2 and the inner metal plate 6 are connected at their tail ends by fingertip joints 5.

[0050] In some embodiments of the present invention, the guide roller may be a pair of rollers 13 or a pair of miniature bearings to reduce contact friction, enhance the mechanical strength and structural life of the overall system, and be suitable for long-term, repeated rehabilitation training.

[0051] Specifically, see Figure 1 One end of the output shaft of the aforementioned push rod motor 11 is connected to the outer metal plate 2 via an adapter nut 8, driving the outer metal plate 2 to move. The displacement of the adapter nut drives the bending movement of the exoskeleton fingers. The other end is connected to a force sensor 9. The flexible bending sensor 3 is installed on the inner surface of the inner metal plate 6. The bending sensor can be replaced by a gyroscope or other sensors capable of measuring bending angles.

[0052] This invention applies a push rod motor 11 to a rehabilitation exoskeleton, enabling the motor to drive the push rod to complete reciprocating linear motion, and the adapter nut 8 to drive the outer metal plate 2 to extend and retract to complete finger bending, thereby realizing rehabilitation training for patients.

[0053] The drive push rod motor 11 drives the adapter nut 8, causing the outer metal plate 2 connected to it to extend and retract. Since one end of the inner metal plate 6 is fixed to the outer metal plate 2 at the fingertip, and the other end is fixed relative to the metacarpal plate 12, the extension and retraction of the outer metal plate 2 is converted into a bending motion, which is transmitted to the inner metal plate 2 through the fingertip joint 5. The roller 13 connected to the bone joint 1 restricts the bending shape of the outer metal plate 2, achieving the bending motion of the metal skeleton and ultimately completing the hand rehabilitation movement. During the process of the exoskeleton driving the finger bending, such as... Figure 1 The bending of the inner metal plate 2 will cause the flexible bending sensor 3 to bend.

[0054] In a preferred embodiment of the present invention, the control module includes an outer loop controller and an inner loop controller, wherein: the outer loop controller generates a target displacement signal based on angle or force error; and the inner loop controller adjusts the output of the drive module based on displacement error.

[0055] As a preferred embodiment of the present invention, see [link to previous document]. Figure 4 and Figure 5 The outer loop controller is a proportional-integral-derivative PID controller, and its input is the feedback signal from the first sensor or the second sensor; the inner loop controller is a position PID controller, and its input is the actual displacement signal of the drive module.

[0056] The control module supports at least three rehabilitation modes: passive mode, based on preset angle trajectory control; assist mode, based on the patient's active force signals to provide proportional assistance; and resistance mode, applying constant resistance to strengthen muscle strength.

[0057] See Figure 4 and Figure 5 The present invention also proposes a control method for the above-mentioned hand exoskeleton robot, comprising the following steps:

[0058] (1) The joint bending angle of the exoskeleton is detected in real time by the first sensor;

[0059] (2) The output force of the drive module is monitored in real time by the second sensor;

[0060] (3) Select control strategies based on rehabilitation models:

[0061] Passive rehabilitation mode: Based on the preset target angle and the joint bending angle fed back by the first sensor, a target displacement signal is generated through the outer ring angle controller;

[0062] Assist / Resistance Mode: Based on the target force and the output force fed back by the second sensor, a target displacement signal is generated through an outer loop force controller;

[0063] (4) Obtain the actual displacement of the drive module through the motor potentiometer, and adjust the output of the drive module through the inner loop position controller based on the deviation between the target displacement signal and the actual displacement.

[0064] (5) Repeat steps (1)-(4) to achieve closed-loop control of joint angle or output force.

[0065] This invention achieves high-precision passive rehabilitation through cascade closed-loop control of motor position and flexible bending sensor 3 angle: the inner loop adjusts the output shaft position of the geared motor in real time based on the motor potentiometer to drive the exoskeleton to complete the preset theoretical joint angle; the outer loop directly captures the patient's actual joint angle through the flexible bending sensor 3, dynamically calculates the deviation from the theoretical value, and corrects the target position of the motor in reverse, forming an iterative closed loop of "mechanical transmission-physiological feedback".

[0066] This invention achieves assisted bending and resistance training through closed-loop control of the output force of the exoskeleton: the system uses force sensors to collect data in real time and combines PID control algorithms to dynamically adjust the torque of the drive motor. When the patient actively flexes and extends their fingers, it automatically provides proportional assistance to help the patient smoothly complete the grasping action; when it is necessary to strengthen muscle strength, it dynamically increases the reverse tension so that the fingers bear precise and controllable adaptive resistance throughout the flexion and extension process.

[0067] As can be seen, this invention uses an exoskeleton to mechanically drive the fingers to complete preset trajectory movements, allowing patients to achieve passive rehabilitation without actively exerting force. When the patient attempts to actively flex, the robot can detect the mechanical intent in real time and provide proportional assistance to achieve assisted bending. Furthermore, when the patient actively moves, the robot can also apply directional resistance to induce adaptive muscle hyperplasia, achieving resistance training. Through these functions, the robot can realize a progressive rehabilitation process of "passive rehabilitation - assisted bending - resistance training," effectively improving the limitations of existing exoskeletons and achieving more personalized and efficient rehabilitation training.

[0068] In summary, this invention proposes a hand exoskeleton robot based on progressive rehabilitation. This robot uses a closed-loop control system to drive flexible plates and force sensors to output tension to the exoskeleton, and employs flexible bending sensors to achieve a closed-loop control of joint angle and position. This allows the wearer to achieve a progressive rehabilitation process of "passive rehabilitation - assisted bending - resistance training." Furthermore, by adjusting the driving tension, additional force can be provided to the wearer's hand to assist in grasping and pinching movements. This invention realizes a progressive rehabilitation process from passive isometric rehabilitation to active isotonic rehabilitation to active resistance rehabilitation, and provides additional force to the wearer's hand as a force-enhancing exoskeleton.

[0069] The above description is merely an embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any equivalent structural or procedural transformations made based on the content of the present invention specification and drawings, or direct or indirect applications in other related system fields, are similarly included within the scope of protection of the present invention.

Claims

1. A hand exoskeleton robot based on progressive rehabilitation, characterized in that, include: The drive module is used to provide linear drive force; A skeletal structure, comprising relatively movable rigid components and flexible connection structures, is used to convert the linear driving force into flexing motion of the fingers; The sensing module includes a first sensor for detecting joint angles and a second sensor for monitoring output force. The control module adjusts the output of the drive module through cascade closed-loop control based on the feedback signals from the first and second sensors.

2. The hand exoskeleton robot based on progressive rehabilitation according to claim 1, characterized in that: The first sensor is a flexible bending sensor (3), which is attached to the inner side of the skeletal structure; The second sensor is a force sensor (9), which is installed at the output end of the drive module.

3. The hand exoskeleton robot based on progressive rehabilitation according to claim 2, characterized in that: The drive module includes a push rod motor (11), and the second sensor is coaxially arranged with the push rod motor (11); The skeletal structure includes a sliding binding (4) and at least one pair of flexible plates that allow bending motion via guides; the upper part of the sliding binding (4) is provided with guides to guide the movement direction of the flexible plates, and the lower part is provided with bindings to fix the patient's fingers.

4. The hand exoskeleton robot based on progressive rehabilitation according to claim 3, characterized in that: The resilient plate includes an outer metal plate (2) and an inner metal plate (6), and the guide includes a skeletal joint (1); The skeletal joint (1) is fixed on the inner metal plate (6). The skeletal joint (1) is provided with a guide groove or guide roller, which guides the movement direction of the outer metal plate (2). The outer metal plate (2) and the inner metal plate (6) are connected at their tail ends by fingertip joints (5).

5. The hand exoskeleton robot based on progressive rehabilitation according to claim 4, characterized in that: One end of the output shaft of the push rod motor (11) drives the outer metal plate (2) to move, and the other end is connected to the force sensor (9); The flexible bending sensor (3) is mounted on the inner metal plate (6).

6. The hand exoskeleton robot based on progressive rehabilitation according to claim 5, characterized in that: The control module includes an outer loop controller and an inner loop controller, wherein: The outer loop controller generates a target displacement signal based on angle or force error; The inner loop controller adjusts the output of the drive module based on the displacement error.

7. The hand exoskeleton robot based on progressive rehabilitation according to claim 6, characterized in that: The outer loop controller is a proportional-integral-derivative PID controller, and the input is the feedback signal from the first sensor or the second sensor; The inner loop controller is a position PID controller, and the input is the actual displacement signal of the drive module.

8. A hand exoskeleton robot based on progressive rehabilitation according to claim 7, characterized in that: The skeletal structure includes a metacarpal plate (12), which is fixed to the wrist by a binding assembly. A push rod motor (11) and a force sensor (9) are mounted on the metacarpal plate (12) using a motor bracket (7) and a force sensor bracket (10), respectively.

9. A hand exoskeleton robot based on progressive rehabilitation according to claim 8, characterized in that: The control module supports at least three rehabilitation modes: Passive mode, based on preset angle trajectory control; Assist mode provides proportional assistance based on the patient's active exertion signals; Resistance mode applies constant resistance to strengthen muscles.

10. A control method for a hand exoskeleton robot as described in claim 9, characterized in that, Includes the following steps: (1) The joint bending angle of the exoskeleton is detected in real time by the first sensor; (2) The output force of the drive module is monitored in real time by the second sensor; (3) Select control strategies based on rehabilitation models: Passive rehabilitation mode: Based on the preset target angle and the joint bending angle fed back by the first sensor, a target displacement signal is generated through the outer ring angle controller; Assist / Resistance Mode: Based on the target force and the output force fed back by the second sensor, a target displacement signal is generated through an outer loop force controller; (4) Obtain the actual displacement of the drive module through the motor potentiometer, and adjust the output of the drive module through the inner loop position controller based on the deviation between the target displacement signal and the actual displacement. (5) Repeat steps (1)-(4) to achieve closed-loop control of joint angle or output force.

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