Auxiliary system for knee joint rehabilitation and control method

Abstract

The present invention relates to an assistance system for knee joint rehabilitation, the assistance system comprising: a joint assistance unit mounted about a knee joint of a user, comprising a first drive and a second drive for supporting and assisting active or passive movement of the knee joint, wherein the first driver and the second driver are in transmission coupling with each other; the control unit is mounted on the leg and used for controlling the first driver and the second driver based on the motion state of the knee joint so as to assist the knee joint in active or passive motion. Through linkage cooperation of pneumatic drive and line drive, large output force and quick response are provided to assist the knee joint in active or passive movement, the requirements of knee joint postoperative patients and long-term bedridden patients for home rehabilitation are met, and the knee joint rehabilitation device has the advantages of being light in weight, portable, comfortable to wear and the like. The invention further relates to a control method using the knee joint rehabilitation assisting system.

Description

Technical Field

[0001] The present invention relates to the technical field of medical auxiliary rehabilitation, and in particular to an auxiliary system and a control method for knee joint rehabilitation. Background Art

[0002] The knee joint bears the important functions of supporting body weight, walking and exercise. However, due to the frequent high-intensity and high-load exercise state, the knee joint has become the most frequently injured joint; most surviving patients after stroke will also have problems with lower limb dysfunction such as hemiplegia and muscle weakness, which seriously affect their normal work and life. CPM (Continuous Passive Motion) is a technology that achieves slow and continuous joint movement through mechanical devices. It is mainly used for postoperative rehabilitation, prevention of joint stiffness and promotion of functional recovery. Although CPM technology has shown great potential in the field of rehabilitation, the CPM equipment currently used in hospitals and rehabilitation institutions is mostly high-priced imported products. Rigid equipment not only cannot simulate the complexity of joint movement, but may even cause secondary damage due to improper pressure or movement, which limits its popularity and application. Therefore, how to develop an auxiliary device dedicated to knee joint rehabilitation, which can assist patients with knee joint disorders in rehabilitation training, help them restore joint mobility, enhance muscle strength, and improve joint stability, is an urgent problem that needs to be solved. Summary of the invention

[0003] In response to the technical problems existing in the prior art, the first purpose of the present invention is to provide an auxiliary system for knee joint rehabilitation, including a joint auxiliary unit and a control unit, which provides a large output force and a fast response through the linkage of pneumatic drive and linear drive to assist the knee joint in active or passive movement, meet the needs of patients after knee surgery and long-term bedridden patients for home rehabilitation, and also has the advantages of light weight, portability, and comfortable wearing.

[0004] The second object of the present invention is to provide a control method using a knee joint rehabilitation auxiliary system to achieve active or passive rehabilitation training of the knee joint through a preset program control mode or a real-time control mode.

[0005] In order to achieve the above object, the present invention adopts the following technical solution:

[0006] An auxiliary system for knee joint rehabilitation, the auxiliary system comprising: a joint auxiliary unit, which is installed around the user's knee joint, and includes a first driver and a second driver, which are used to support and assist the active or passive movement of the knee joint, wherein the first driver and the second driver are coupled to each other; a control unit installed on the leg, the control unit is used to control the first driver and the second driver based on the movement state of the knee joint to assist the active or passive movement of the knee joint.

[0007] Furthermore, the first driver has a foldable bellows, on which a plurality of expandable and contractible filling parts are formed at certain intervals along the length direction thereof, and an expansion and contraction space for filling gas is formed together inside the foldable bellows.

[0008] Furthermore, an inflatable component is provided in the expansion and contraction space, and the inflatable component includes a plurality of airbag parts arranged in series, one end of each of the plurality of airbag parts is connected in series through an air tube, the end of the air tube extends from the expandable and contractible filling part at the tail end to the outside and is connected to the control unit, and the airbag part is placed in the expandable and contractible filling part to expand or contract it.

[0009] Furthermore, the bottom of the foldable bellows is provided with an opening for receiving the inflatable component.

[0010] Furthermore, the second driver includes at least one tendon line, one end of which is fixed to the expandable filling part at the head end, and the other end of which passes through multiple expandable filling parts in sequence and extends from the expandable filling part at the tail end to the outside, and is then connected to the control unit, which is used to drive the multiple expandable filling parts to fold along the length direction of the foldable bellows.

[0011] Furthermore, an included angle between the expandable and shrinkable filling portion at the head end and the expandable and shrinkable filling portion at the tail end is 20°-180°.

[0012] Furthermore, the control unit includes a shell that is wrapped around the user's legs, and a first air pump and a second air pump are provided on one side of the shell, the first air pump and the second air pump are connected to the first driver through a pipeline, a motor is provided in the shell, the motor is connected to the second driver, and a controller for controlling the action of the first air pump, the second air pump and the motor is provided, and the first air pump, the second air pump and the motor are respectively communicated with the controller.

[0013] Furthermore, the pipeline is provided with a pressure sensor for monitoring gas pressure, and the pressure sensor is communicatively connected to the controller. The leg is provided with at least two angle sensors for real-time monitoring of the flexion and extension angles of the knee joint, and the angle sensors are communicatively connected to the controller.

[0014] A control method utilizing a knee joint rehabilitation auxiliary system, the control method comprising a first control mode, in which: time parameters t1, t2, t3, t4 of four motion states of knee flexion, knee flexion and knee extension are pre-set in the controller, and the motor is set to a constant speed working mode; when the knee joint is in an extended state, it is set to an initial state, and when the knee joint is in a flexed state, the controller sends an instruction to control the motor to pull the tendon line and start the first air pump to extract the gas in the expandable and shrinkable filling part, so that the expandable and shrinkable filling part contracts and folds and drives the knee joint to flex to a preset time t1, and then maintains the flexed state for t2 time; then the controller sends an instruction to control the motor to release the tendon line and start the second air pump to inflate the expandable and shrinkable filling part, so that the expandable and shrinkable filling part expands and stretches and drives the knee joint to stretch to a preset time t3, and then maintains the extended state for t4 time; this cycle is repeated to achieve passive rehabilitation training of the knee joint.

[0015] A control method utilizing a knee joint rehabilitation assisting system, the control method comprising a second control mode, in which: the controller determines the user's knee joint movement state based on real-time data from the pressure sensor and the angle sensor; when it is detected that the knee joint angle is decreasing, it is identified as a knee flexion movement, and the controller sends an instruction to control the motor to pull the tendon line and start the first air pump to extract the gas in the expandable filling part, and when the preset knee flexion angle and air pressure are reached, the motor and the first air pump are stopped; when it is detected that the knee joint angle is increasing, it is identified as a knee extension movement, and the controller sends an instruction to control the motor to release the tendon line and start the second air pump to inflate the expandable filling part, and when the preset knee extension angle and air pressure are reached, the motor and the second air pump are stopped; this cycle is repeated, thereby responding to and assisting the user's active or passive knee joint movement in real time.

[0016] The present invention has the following advantages:

[0017] 1. The present invention can support and assist the active or passive movement of the knee joint through the mutual transmission coupling of the first driver and the second driver in the joint auxiliary unit, and effectively promote the rehabilitation process. The first driver adopts a foldable bellows, which is equipped with multiple expandable filling parts and an inflatable component. The first air pump and the second air pump work together to achieve rapid gas filling and discharge, providing stable support for the knee joint. The foldable bellows achieves variable stiffness through the combination of pneumatic and linear drive, and can adapt to the motion trajectory of the knee joint. Since the articular cartilage will be deformed by force during the movement of the knee joint, the position of the knee joint rotation axis will shift with the rotation of the joint, forming a unique "ebb" motion trajectory. The foldable bellows of the present invention can well match the motion trajectory of the knee joint through the structural design of the soft actuator and the ingenious method of joint driving of the tendon line + airbag part. The second driver is used for the folded state of multiple expandable filling parts, and the tendon line is driven by the motor to generate tension, which pulls the expandable filling parts together during the deflation process. This not only avoids sudden force changes during deflation, but also ensures that the expandable and contractible filling part forms a preset angle when folded, thereby improving the stability of the knee joint during movement. If there is no second driver, the bellows can be stretched or folded only by the pneumatic control of the first driver. However, during the deflation process, due to the lack of tension regulation of the tendon line, the expandable and contractible filling part will suddenly lose support due to the rapid release of gas, resulting in a sudden change in force, which in turn affects the stability and rehabilitation effect of the knee joint. The addition of the second driver effectively solves this problem, so that the entire joint auxiliary unit can provide stable support while ensuring smooth transition and rehabilitation of the knee joint during movement. In addition, the movement and force of the tendon line are linear. In contrast, the force generated by pure pneumatic control is nonlinear, which will cause discomfort to the user and increase the difficulty of control. Therefore, the setting of the second driver improves the performance of the joint auxiliary unit and improves the user's rehabilitation experience and comfort.

[0018] 2. The control unit of the present invention has two control modes. One is to control the actions of the first driver and the second driver according to the motion state of the knee joint, and perform rehabilitation training of knee flexion, knee flexion and knee extension in a reciprocating manner, simulating natural knee joint movement, promoting muscle and joint recovery, achieving precise assistance, supporting preset time parameters of multiple motion states and constant speed working modes of the motor, and meeting personalized rehabilitation needs. The second is to integrate pressure sensors and angle sensors, dynamically judge the motion state of the knee joint according to real-time data, respond to and adjust the driver actions in real time, and improve the flexibility and efficiency of rehabilitation training.

[0019] 3. The joint auxiliary unit and control unit of the present invention constitute a flexible robot, which is applied to rehabilitation equipment to reduce costs and improve structural flexibility and compliance. It eliminates non-driven freedom restrictions, reduces joint alignment problems, and prevents secondary damage to joints caused by rigid equipment. The combination of flexible design and intelligent control makes home-based rehabilitation possible and improves the convenience and accessibility of rehabilitation. By adjusting the air pump pressure and motor control speed, different telescopic performance and driving force can be achieved, and the output force and speed can be flexibly adjusted to provide more possibilities for rehabilitation training. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a schematic diagram of the three-dimensional structure of the auxiliary system for knee joint rehabilitation based on the first control mode of the present invention.

[0021] Figure 2 It is a three-dimensional structural schematic diagram of the joint auxiliary unit of the present invention.

[0022] Figure 3 It is a three-dimensional structural schematic diagram of the joint auxiliary unit of the present invention from another angle.

[0023] Figure 4 It is a three-dimensional cutaway view of the joint assist unit of the present invention.

[0024] Figure 5 It is a three-dimensional cutaway view of the foldable bellows of the present invention.

[0025] Figure 6 It is a three-dimensional structural schematic diagram of the foldable bellows of the present invention during the folding process.

[0026] Figure 7 It is a three-dimensional structural schematic diagram of the control unit of the present invention.

[0027] Figure 8 It is a schematic diagram of the three-dimensional structure of another embodiment of the auxiliary system for knee joint rehabilitation based on the second control mode of the present invention.

[0028] Fig. 9 It is a schematic diagram of the control flow of the auxiliary system for knee joint rehabilitation under the first control mode of the present invention.

[0029] Fig.10 It is a schematic diagram of the control flow of the auxiliary system for knee joint rehabilitation under the second control mode of the present invention.

[0030] Among them, 1 is a joint auxiliary unit, 101 is a first driver, 101a is a foldable bellows, 101a1 is an expandable filling part, 101a2 is an expansion and contraction space, 101a3 is an opening, 101b is an inflatable component, 101b1 is an airbag part, 101b2 is an air tube, 101b3 is a three-way valve, 101b4 is a perforation, 102 is a second driver, 102a is a tendon line, 102b is a through hole, 2 is a control unit, 201 is a shell, 201a is a control switch, 201b is a wire port, 201c is a mounting slot, 202 is a first air pump, 203 is a second air pump, 204 is a controller, 205 is a pressure sensor, 206 is an angle sensor, 3 is a strap, 4 is a knee joint, 5 is a thigh, and 6 is a calf. DETAILED DESCRIPTION

[0031] The following description is essentially only exemplary and is not intended to limit the present invention, its application or use. It will be further understood that the term "include" and / or "comprising" specifies the existence of the features, wholes, steps, operations, elements and / or parts described when used in this specification, but does not exclude the existence of one or more other features, wholes, steps, operations, elements, parts and / or its groups or add one or more other features, wholes, steps, operations, elements, parts and / or its groups. As used in this article, the term "and / or" includes any and all combinations of one or more of the associated listed items. It will be understood that when an element, component and / or part is referred to as "connected to another element, component and / or part", it can be directly connected to another element, component and / or part, or there can be an intermediate element. It will be understood that although the terms "first", "second" and the like can be used to describe various elements, components and / or parts in this article, these elements, components and / or parts should not be limited by these terms. These terms are only used to distinguish an element, component or part from another element, component or part. Therefore, the first element, part or part discussed below can be referred to as the second element, part or part without departing from the teaching of the present invention. Unless otherwise defined, all terms (including technical terms and scientific terms) used in this article have the same meanings as those commonly understood by those of ordinary skill in the field to which the present invention belongs. It will be further understood that terms such as those defined in commonly used dictionaries should be interpreted as having meanings consistent with their meanings in the relevant field and / or the context of this specification, and will not be interpreted in an idealized or overly formal sense, unless clearly defined in this article.

[0032] It should be understood that, in order to clearly show the contents therein, the drawings herein are not drawn to scale, and the same or similar reference numerals indicate the same or similar components or parts. In addition, it should be understood that any embodiments described in this application and the technical features included therein can be combined with each other.

[0033] The present invention will be further described in detail below with reference to the accompanying drawings and specific implementation methods.

[0034] like Figure 1 As shown, an auxiliary system for knee joint rehabilitation mainly includes a joint auxiliary unit 1 and a control unit 2. The joint auxiliary unit 1 is installed around the user's knee joint 4, and includes a first driver 101 and a second driver 102, which are used to support and assist the active or passive movement of the knee joint 4, thereby assisting the user in walking or rehabilitation exercises, wherein the first driver 101 and the second driver 102 are mutually coupled in transmission. The control unit 2 is installed on the leg, which can be installed on the thigh 5 or the calf 6, and controls the first driver 101 and the second driver 102 based on the movement state of the knee joint 4 to assist the active or passive movement of the knee joint 4.

[0035] like Figure 2-6 As shown, the first driver 101 is a flexible driver, which has a foldable bellows 101a, which is constructed based on 3D printing. The foldable bellows 101a is made of TPU98, TPU95, TPU90 or TPU85, preferably TPU95 (thermoplastic polyurethane elastomer 95A hardness). This material not only has good elasticity and wear resistance, but also can achieve good foldability and recovery while ensuring strength, and adapt to the complex movement requirements of the knee joint 4. The foldable bellows 101a is extended along the length direction of the leg, and its bottom is attached to the inner side of the knee joint 4, ensuring that the foldable bellows 101a can fit the contour of the knee joint 4 when extending and contracting, reducing unnecessary friction and resistance. The bottom of the foldable bellows 101a also has at least two straps 3, one of which is fixed to the thigh 5, and the other is fixed to the calf 6, so that the middle position of the foldable bellows 101a corresponds to the knee joint 4 to better simulate the movement path of the knee joint 4. It is understandable that the fixing of the foldable bellows 101a is not limited to the straps 3, and a quick fixing device such as Velcro can also be used, or the foldable bellows 101a can be installed on the knee pad.

[0036] Continue to refer to Figure 2-6, a plurality of expandable and contractible filling parts 101a1 are formed at certain intervals along the length direction of the foldable bellows 101a, and the plurality of expandable and contractible filling parts 101a1 are located at the top of the foldable bellows 101a, and their orientation is opposite to the knee joint 4. When the foldable bellows 101a is in an extended state, the plurality of expandable and contractible filling parts 101a1 extend at certain intervals along the length direction of the foldable bellows 101a, so that the cross section of the foldable bellows 101a is fan-shaped, and the maximum extension angle is 180 degrees. When the foldable bellows 101a is folded, the plurality of expandable and contractible filling parts 101a1 are stacked together in sequence, so that the cross section thereof is generally V-shaped. Among them, the interior of the plurality of expandable and contractible filling parts 101a1 jointly forms an expansion and contraction space 101a2 for filling gas, and the expansion or contraction state of the expandable and contractible filling parts 101a1 can be controlled by inputting or outputting gas therein. When gas is input into the expansion and contraction space 101a2, the expandable and contractible filling portion 101a1 expands accordingly, thereby pushing the foldable bellows 101a to unfold into a fan shape; when the gas is discharged, the expandable and contractible filling portion 101a1 contracts, and at the same time, based on the linear drive of the second driver 102, the foldable bellows 101a is folded into a V shape, so as to realize the reciprocating switching of the foldable bellows 101a between the fan shape and the V shape, thereby providing a stable and adjustable auxiliary support force for the rotational movement of the knee joint 4.

[0037] Next reference Figure 4 and Figure 5An inflatable component 101b is arranged in the expansion and contraction space 101a2, which is used to drive the expandable and contractible filling part 101a1 to realize the expansion and contraction functions. The inflatable component 101b includes a plurality of airbag parts 101b1 arranged in series. The airbag part 101b1 is a sheet-like hollow structure, which matches the shape of the expandable and contractible filling part 101a1. One end of each of the plurality of airbag parts 101b1 has a through hole 101b4, and the air tube 101b2 passes through the plurality of through holes 101b4 to connect the plurality of airbag parts 101b1 in series, and the end of the air tube 101b2 extends from the expandable and contractible filling part 101a1 at the tail end to the outside and is connected to the control unit 2 to form a closed-loop system for gas delivery. The airbag part 101b1 is placed in the expandable and shrinkable filling part 101a1 to expand or shrink it, wherein the air tube 101b2 has a plurality of vents, and the vents correspond to the internal space of the airbag part 101b1. When the control unit 2 is started and the gas is transported through the air tube 101b2, the gas is evenly distributed to each airbag part 101b1 through the vents, thereby driving them to expand or shrink synchronously, ensuring the stability and synchronization of the expandable and shrinkable filling part 101a1 when it is stretched and folded. In this embodiment, the number of the expandable and shrinkable filling parts 101a1 is eight, and the number of the airbag parts 101b1 is also eight. Each airbag part 101b1 is placed in the expandable and shrinkable filling part 101a1, and the gas is transported to the eight airbag parts 101b1 through the air tube 101b2, so that the eight expandable and shrinkable filling parts 101a1 expand or shrink synchronously. The airbag part 101b1 is sewn from 210D TPU composite cloth.

[0038] The bottom of the foldable bellows 101a is provided with an opening 101a3 for receiving the inflatable component 101b. The bottoms of the expandable filling part 101a1 at the head end and the expandable filling part 101a1 at the tail end are both provided with an annular base, one of which is attached to the upper inner side of the knee joint 4, and the other is attached to the lower inner side of the knee joint 4. The opening 101a3 is located between the two annular bases, and the opening 101a3 corresponds to the inner side of the knee joint 4, and is located on the central axis of the foldable bellows 101a. On the one hand, the opening 101a3 serves as a passage for the inflatable component 101b to enter the expansion and contraction space 101a2. On the other hand, it serves as the axis point of the foldable bellows 101a during the movement process, so that the multiple expandable filling parts 101a1 can move axially around the central axis, ensuring that the multiple expandable filling parts 101a1 can maintain consistency with the movement path of the knee joint 4, and provide accurate and stable auxiliary support.

[0039] The included angle between the expandable and shrinkable filling portion 101a1 at the head end and the expandable and shrinkable filling portion 101a1 at the tail end is 20°-180°.

[0040] like Figure 2-6As shown, the second driver 102 includes at least one tendon line 102a, which realizes precise control of multiple expandable and contractible filling parts 101a1 to drive them to fold in the length direction of the foldable bellows 101a. One end of the tendon line 102a is fixed to the expandable and contractible filling part 101a1 at the head end, and the other end of the tendon line 102a passes through multiple expandable and contractible filling parts 101a1 in sequence and extends from the expandable and contractible filling part 101a1 at the tail end to the outside, and then connects to the control unit 2. The upper part of the expandable and contractible filling part 101a1 has a through hole 102b, which provides a channel for the tendon line 102a to penetrate, and the tendon line 102a connects multiple expandable and contractible filling parts 101a1 in series through the through hole 102b. When the control unit 2 receives the instruction, it will start to wind and pull the tendon line 102a. Under the pulling force of the tendon line 102a, the expandable filling part 101a1 at the head end begins to gradually approach the expandable filling part 101a1 at the tail end, and then multiple expandable filling parts 101a1 begin to overlap along the predetermined path of the tendon line 102a until the expected folding state is reached. In this embodiment, the number of tendon lines 102a is two, and the two tendon lines 102a are symmetrically arranged on the upper part of the expandable filling part 101a1 to enhance the stability and reliability of the line drive. The setting of the tendon line 102a not only avoids the sudden change of force of the foldable bellows 101a during the deflation process, but also ensures that the expandable filling part forms a preset angle when folded, thereby improving the stability of the knee joint during movement.

[0041] like Figure 7As shown, the control unit 2 includes a housing 201 wound around the user's leg. The housing 201 has a rectangular structure and is constructed based on a 3D printing mechanism, with a material of PLA1.75. On one side of the housing 201, there are a first air pump 202 and a second air pump 203. Specifically, there are two mounting grooves 201c on one side of the housing 201, and the first air pump 202 and the second air pump 203 are respectively embedded in the two mounting grooves 201c. The first air pump 202 is used to extract the gas in the inflatable assembly 101b to achieve the contraction of the expandable and contractible filling part 101a1, while the second air pump 203 is used to inflate the inflatable assembly 101b to drive the expansion of the expandable and contractible filling part 101a1. The first air pump 202 and the second air pump 203 are connected to the first driver 101 through pipelines. Specifically, the first air pump 202 and the second air pump 203 are connected to the inflatable assembly 101b through an air pipe 101b2. A three-way valve 101b3 is configured on the air pipe 101b2. The first end of the three-way valve 101b3 is connected to the airbag part 101b1 of the inflatable assembly 101b, the second end is connected to the first air pump 202, and the third end is connected to the second air pump 203 to facilitate the adjustment of the gas flow direction and flow rate. A motor (not shown in the figure) is provided inside the housing 201, and the motor is connected to the second driver 102. Specifically, the motor is connected to the tendon line 102a. By driving the motor to pull or release the tendon line 102a, multiple expandable and contractible filling parts 101a1 can be folded or extended. A controller 204 for controlling the actions of the first air pump 202, the second air pump 203, and the motor is provided inside the housing 201. The first air pump 202, the second air pump 203, and the motor are respectively communicatively connected to the controller 204. The controller 204 uses an ESP32-wroom single-chip microcomputer based on Ardiuno as the core processing unit. Among them, there is also a power supply inside the housing 201. The power supply is respectively electrically connected to the first air pump 202, the second air pump 203, the motor, and the controller 204 to supply power to each component in the control unit 2. The power supply is a 7.4V lithium-ion battery. A control panel is also provided on the outside of the housing 201. The control panel is electrically connected to the controller 204. The user can input instructions through the buttons or touch screen on the control panel to achieve the control of the device. In addition, an emergency stop button is provided on the control panel. The emergency stop button is electrically connected to the controller 204. When the user feels uncomfortable, they can press the emergency stop button to turn off the motor, the first air pump 202, and the second air pump 203 to ensure the safety of wearing. There are a wire port 201b and a control switch 201a on the end wall of the housing 201. The wire port 201b is used to receive the tendon line, and the control switch 201a is used to turn on and off the controller 204.

[0042] As Figure 8As shown, a pressure sensor 205 for monitoring gas pressure is provided on the pipeline, and the pressure sensor 205 is connected to the controller 204 for communication. The maximum air pressure of the airbag is 50kPa, and this value is preset as the termination threshold of the pressure sensor 205, that is, when the air pressure in the airbag reaches or exceeds 50kPa, the device will automatically stop working to prevent the patient from being injured due to excessive air pressure. In the early stage of rehabilitation, since the user's muscle tension is usually large, the airbag part 101b1 needs to provide additional pressure to assist the knee joint 4 to straighten. At this time, the control unit 2 will adjust the air pressure in the airbag part 101b1 according to the preset air pressure value and the real-time monitoring data of the pressure sensor 205 to meet the patient's rehabilitation needs. This operation is a passive motion training of the knee joint. As the rehabilitation process progresses, the user will gradually change from passive motion to active motion, and the auxiliary system can be trained through these two impedance methods: one is to increase resistance by pressurizing the airbag part 101b1, and the other is to adjust resistance by controlling the tension of the tendon line 102a. For example, in the knee flexion action, a certain air pressure can be pre-filled into the airbag part 101b1, so that the user needs to use greater force to complete the knee flexion action, thereby achieving the purpose of exercising muscle strength. In addition, the leg is provided with at least two angle sensors 206 for real-time monitoring of the flexion and extension angles of the knee joint 4. The angle sensor 206 is connected to the controller 204 for communication. The angle sensor 206 monitors the flexion and extension angles of the knee joint 4 in real time and transmits the data to the controller 204 in real time. There are two angle sensors 206, one of which is fixed to the thigh 5 and the other is fixed to the calf 6, so as to more accurately understand the angle changes of the knee joint 4 under different motion states, so as to adjust the working mode and parameters of the joint auxiliary unit 1 according to these data. The angle sensor 206 is a gyroscope, and its model is WT9011DCL-BT50.

[0043] like Fig. 9 As shown, a control method using a knee joint rehabilitation auxiliary system is provided, wherein the control method mainly includes a first control mode and a second control mode. Before conducting knee joint 4 rehabilitation training, a pre-assessment step is required in view of the limited knee flexion angle of the user after knee joint 4 surgery. The user needs to wear or stick a bending sensor first. The sensor can record the angle at which the user feels pain when trying to bend the knee joint 4. This data will be used as the terminal angle limit for the operation of the device to ensure that the rehabilitation training is conducted within a safe and painless range.

[0044] In the first control mode, the time parameters t1, t2, t3, and t4 of the four motion states of knee flexion, knee flexion and knee holding, knee extension, and knee extension and knee holding are pre-set in the controller 204. These parameters can be flexibly adjusted according to the user's rehabilitation progress and the doctor's professional advice. The motor is set to a constant speed working mode to ensure that the pulling and releasing process of the tendon line 102a is smooth and controllable.

[0045] When the knee joint 4 is in the extended state, it is set to the initial state. When the knee joint 4 is converted from the extended state to the flexed state, the controller 204 sends an instruction to control the motor to rotate forward to pull the tendon line 102a, and starts the first air pump 202 to extract the gas in the expandable filling part 101a1. The second air pump 203 is turned off, causing the expandable filling part 101a1 to shrink and fold, and store elastic potential energy inside it. The gas in the airbag part 101b1 is squeezed out, thereby driving the knee joint 4 to flex to the preset time t1.

[0046] After reaching t1, the motor stops pulling the tendon line 102a, and the knee joint 4 remains in the flexed state for t2 time to allow the muscles and joints to adapt to this posture.

[0047] The controller 204 then sends an instruction to control the motor to reverse and release the tendon line 102a, and starts the second air pump 203 to inflate the expandable filling part 101a1. The first air pump 202 is turned off, causing the expandable filling part 101a1 to expand and stretch, and the elastic energy stored inside is released, thereby driving the knee joint 4 to stretch to the preset time t3.

[0048] After reaching t3, the motor stops releasing the tendon line 102a, and the knee joint 4 remains in the extended state for t4 time.

[0049] This cycle is repeated until the predetermined rehabilitation training cycle is completed, thereby achieving passive rehabilitation training of the knee joint 4.

[0050] like Fig.10 As shown, in the second control mode, the controller 204 determines the motion state of the user's knee joint 4 according to the real-time data from the pressure sensor 205 and the angle sensor 206. Specifically, the controller 204, as a core processing unit, continuously receives the real-time data from the pressure sensor 205 and the angle sensor 206. The pressure sensor 205 and the angle sensor 206 monitor the air pressure change and the flexion / extension angle of the knee joint 4, respectively, and provide the controller 204 with motion state information.

[0051] When it is detected that the angle of the knee joint 4 is decreasing, it is identified as a knee flexion action. The controller 204 sends a command to control the motor to rotate forward and pull the tendon line 102a to provide the necessary auxiliary force, and starts the first air pump 202 to extract the gas in the expandable filling part 101a1. The second air pump 203 is turned off, so that the expandable filling part 101a1 shrinks and folds, and stores elastic potential energy inside it. The gas in the airbag part 101b1 is squeezed out, further assisting the flexion action of the knee joint 4. When the preset knee flexion angle and air pressure are reached, that is, when the angle sensor 206 detects the specified angle, the pressure sensor 205 detects the specified pressure, or a stop command is received, the motor stops and self-locks, and the first air pump 202 is turned off at the same time to maintain a certain knee flexion angle.

[0052] When the angle of the knee joint 4 is detected to be increasing, it is identified as a knee extension movement. The controller 204 sends a command to control the motor to reverse and release the tendon line 102a, reducing the resistance against the knee extension movement, and starts the second air pump 203 to inflate the expandable and shrinkable filling part 101a1. The first air pump 202 is turned off, so that the expandable and shrinkable filling part 101a1 expands and stretches, and the elastic energy stored inside is released to provide additional support for the knee extension movement. When the preset knee flexion angle and air pressure are reached, that is, when the pressure sensor 205 reaches a certain value, the angle sensor 206 detects a specified angle or receives a stop command, the motor stops and self-locks, and the second air pump 203 is turned off at the same time to maintain a certain knee extension angle.

[0053] The knee flexion and extension movements are cycled in this way, thereby responding to and assisting the active or passive movement of the user's knee joint 4 in real time.

[0054] The above embodiments are preferred implementation modes of the present invention, but the implementation modes of the present invention are not limited to the above embodiments. Any other changes, modifications, substitutions, combinations, and simplifications that do not deviate from the spirit and principles of the present invention should be equivalent replacement methods and are included in the protection scope of the present invention.

Claims

1. An auxiliary system for knee joint rehabilitation, characterized in that: The auxiliary system includes: A joint assist unit, the joint assist unit is mounted around the user's knee joint, and includes a first driver and a second driver, which are used to support and assist the active or passive movement of the knee joint, wherein the first driver and the second driver are transmission-coupled with each other; A control unit installed on the leg, the control unit is used to control the first driver and the second driver based on the movement state of the knee joint to assist the active or passive movement of the knee joint.

2. The auxiliary system for knee joint rehabilitation according to claim 1, characterized in that: The first driver has a foldable bellows, on which a plurality of expandable and contractible filling parts are formed at certain intervals along the length direction thereof, and an expansion and contraction space for filling gas is formed together inside the foldable bellows.

3. The auxiliary system for knee joint rehabilitation according to claim 2, characterized in that: An inflatable component is arranged in the expansion and contraction space, and the inflatable component includes a plurality of airbag parts arranged in series, one end of each of the plurality of airbag parts is connected in series through an air tube, the end of the air tube extends from the expandable and contractible filling part at the tail end to the outside and is connected to the control unit, and the airbag part is placed in the expandable and contractible filling part to expand or contract it.

4. The auxiliary system for knee joint rehabilitation according to claim 3, characterized in that: The bottom of the foldable bellows is provided with an opening for receiving the inflatable component.

5. The auxiliary system for knee joint rehabilitation according to claim 2, characterized in that: The second driver includes at least one tendon line, one end of which is fixed to the expandable filling part at the head end, and the other end of which passes through multiple expandable filling parts in sequence and extends from the expandable filling part at the tail end to the outside, and is then connected to the control unit, which is used to drive the multiple expandable filling parts to fold along the length direction of the foldable bellows.

6. The auxiliary system for knee joint rehabilitation according to claim 2, characterized in that: The included angle between the expandable and shrinkable filling portion at the head end and the expandable and shrinkable filling portion at the tail end is 20°-180°.

7. The auxiliary system for knee joint rehabilitation according to claim 1, characterized in that: The control unit includes a shell that is wrapped around the user's legs, and a first air pump and a second air pump are arranged on one side of the shell. The first air pump and the second air pump are connected to the first driver through a pipeline. A motor is arranged in the shell, and the motor is connected to the second driver. A controller for controlling the action of the first air pump, the second air pump and the motor is also arranged. The first air pump, the second air pump and the motor are respectively connected to the controller for communication.

8. The auxiliary system for knee joint rehabilitation according to claim 7, characterized in that: The pipeline is provided with a pressure sensor for monitoring gas pressure, and the pressure sensor is communicatively connected to the controller. The leg is provided with at least two angle sensors for real-time monitoring of the flexion and extension angles of the knee joint, and the angle sensors are communicatively connected to the controller.

9. A control method using the knee joint rehabilitation auxiliary system according to any one of claims 1 to 8, characterized in that: The control method comprises a first control mode, in which: Presetting the time parameters t1, t2, t3, t4 of four motion states of knee flexion, knee flexion and holding, knee extension and knee extension and holding in the controller, and setting the motor to a constant speed working mode; When the knee joint is in an extended state, it is set as an initial state. When the knee joint is in a flexed state, the controller sends an instruction to control the motor to pull the tendon line and start the first air pump to extract the gas in the expandable filling part, so that the expandable filling part shrinks and folds and drives the knee joint to flex to a preset time t1, and then maintains the flexed state for t2 time; Then, the controller sends an instruction to control the motor to release the tendon line and start the second air pump to inflate the expandable filling part, so that the expandable filling part expands and stretches and drives the knee joint to stretch for a preset time t3, and then maintains the knee extension state for a time t4; This cycle is repeated to achieve passive rehabilitation training of the knee joint.

10. A control method using the knee joint rehabilitation auxiliary system according to any one of claims 1 to 8, characterized in that: The control method includes a second control mode, in which: The controller determines the user's knee joint movement state based on real-time data from the pressure sensor and the angle sensor; When it is detected that the knee joint angle is decreasing, it is identified as a knee flexion action, and the controller sends an instruction to control the motor to pull the tendon line and start the first air pump to extract the gas in the expandable filling part, and when the preset knee flexion angle and air pressure are reached, the motor and the first air pump are stopped; When it is detected that the knee joint angle is increasing, it is identified as a knee extension action, and the controller sends an instruction to control the motor to release the tendon line and start the second air pump to inflate the expandable filling part, and when the preset knee extension angle and air pressure are reached, the motor and the second air pump are stopped; This cycle repeats itself, thereby responding to and assisting the user's active or passive movement of the knee joint in real time.

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