Wire-driven variable stiffness hand function rehabilitation device

Abstract

The present application belongs to the technical field of rehabilitation medical apparatus and instruments, and particularly relates to a wire-driven variable stiffness hand function rehabilitation device, which comprises a palm mounting block and a control module. The front side of the palm mounting block is provided with a finger execution assembly, and the top surface of the palm mounting block is provided with a variable stiffness driving assembly. The finger execution assembly comprises a fingertip sleeve, an open ring, a fixed spring plate and a driving rope. The variable stiffness driving assembly comprises a variable stiffness driving module, a sliding spring plate and a guide rail assembly. The bottom surface of the palm mounting block is fixedly provided with a Bowden cable. The core wire of the Bowden cable is connected with the driving rope. The other end of the Bowden cable is connected with a Bowden cable driving module. The variable stiffness driving module and the Bowden cable driving module are connected with the control module. Through the collaborative design of the wire driving and the variable stiffness structure, the mechanical properties of the human finger flexion and extension are simulated, the weightless traction of the finger flexion and the dynamic regulation and control of the extensor muscle simulation stiffness are realized, and the personalized training needs of patients in different rehabilitation stages are adapted.

Description

Technical Field

[0001] This invention belongs to the field of rehabilitation medical device technology, specifically relating to a line-driven variable stiffness hand function rehabilitation device, which is suitable for rehabilitation training of patients with hand motor dysfunction. It can dynamically adjust the simulated stiffness of finger extensor muscles according to different rehabilitation stages to achieve personalized and precise hand rehabilitation training. Background Technology

[0002] In the field of rehabilitation medicine, hand function rehabilitation training is an important rehabilitation method for patients with hand motor dysfunction caused by stroke, spinal cord injury, peripheral nerve injury, etc. By simulating the flexion and extension movements of human fingers, it gradually restores the muscle strength, joint flexibility, and motor coordination of the patient's hand. The tension and stiffness of the extensor muscles on the back of the fingers are key biomechanical factors affecting finger flexion and extension movements. Patients at different stages of rehabilitation have significant differences in the tolerance and force exertion of their hand muscles, requiring training with different simulated extensor muscle stiffness.

[0003] Currently, existing hand function rehabilitation devices have the following shortcomings: 1) Limitations in stiffness adjustment: Traditional rehabilitation devices often use fixed values ​​for the simulated stiffness of finger extensor muscles, or the adjustment of finger tension is cumbersome and the stiffness adaptability is poor. They cannot adjust the simulated stiffness of finger extensor muscles in real time and dynamically according to the patient's rehabilitation progress, making it difficult to meet the needs of personalized rehabilitation training. Although the wire-driven device solves the weight-bearing problem, it lacks an effective variable stiffness structure and has poor stiffness adaptability.

[0004] 2) Wearing and weight-bearing issues: Some rehabilitation devices adopt an integrated wearable design of motor and drive structure, which puts a lot of weight on the hands, easily causing fatigue in the patient's hands and affecting the naturalness of finger flexion and extension movements.

[0005] 3) Low mechanical matching degree: The existing variable stiffness rehabilitation device lacks coordinated design between the stiffness adjustment structure and the line drive traction structure. The adjustment of the extensor muscle simulated stiffness is not synchronized with the traction of the finger bending movement, which cannot accurately simulate the natural mechanical characteristics of human finger flexion and extension, thus limiting the rehabilitation training effect.

[0006] Therefore, developing a line-driven hand function rehabilitation device that is easy to wear, has low hand load, and can achieve simulated stiffness adjustment of finger extensor muscles is of great application value and promotion significance in the field of rehabilitation medicine, effectively matching the training needs of patients at different rehabilitation stages. Summary of the Invention

[0007] To address the technical problems of existing hand function rehabilitation devices, such as cumbersome stiffness adjustment, poor adaptability, high wearing load, and low mechanical matching, this invention provides a line-driven variable stiffness hand function rehabilitation device. This device achieves low-load flexion and extension traction of the fingers through a line-driven structure, and combines a gear and rack control spring plate displacement adjustment structure to achieve control of the simulated stiffness of the finger extensor muscles. Simultaneously, it considers the ease of wearing the device and its structural stability, meeting the personalized training needs of patients at different rehabilitation stages.

[0008] The objective of this invention is achieved through the following technical solution. According to the present invention, a line-driven variable stiffness hand function rehabilitation device includes a palm mounting block for wearing on the palm and a control module. The front side of the palm mounting block is provided with a finger execution component corresponding to the finger, and the top surface is provided with a variable stiffness drive component corresponding to the finger execution component. The finger execution component includes a fingertip sleeve worn on the fingertip, several open rings distributed on the fingers, a fixed spring plate whose one end is fixed to the top of the fingertip sleeve and the other part slides through the top of the open ring, and a drive rope connected to the bottom of the fingertip sleeve and the open ring. The variable stiffness drive component includes a variable stiffness drive module fixedly disposed on the top surface of the palm mounting block, a sliding spring plate connected to the variable stiffness drive module for telescopic movement, and a guide rail assembly fixedly disposed on the top surface of the palm mounting block for sliding guidance of the sliding spring plate. The sliding spring plate can slide back and forth on the top of the open ring and the fingertip sleeve. A Bowden wire is fixedly disposed on the bottom surface of the palm mounting block. The core wire of the Bowden wire is connected to the drive rope, and the other end of the Bowden wire is connected to the Bowden wire drive module. The variable stiffness drive module and the Bowden wire drive module are connected to the control module.

[0009] Compared with the prior art, the advantages of the present invention are: The line-driven variable stiffness hand function rehabilitation device of the present invention, through the synergistic design of line drive and variable stiffness structure, can simulate the mechanical characteristics of human finger flexion and extension, realize the weightless traction of finger flexion and extension and the dynamic control of extensor muscle simulated stiffness, adapt to the personalized training needs of patients at different rehabilitation stages, and is suitable for rehabilitation training of patients with different degrees of hand motor dysfunction. The structure is lightweight and easy to wear, and can be widely used in rehabilitation medical institutions and home rehabilitation training scenarios.

[0010] The control module enables coordinated control of the variable stiffness drive component and the Bowden line drive module. The stiffness adjustment is precisely matched with the traction force and frequency of finger flexion and extension, which can simulate the natural mechanical characteristics of human finger flexion and extension and improve the effect of rehabilitation training.

[0011] Furthermore, the tops of the fingertip sleeve and the opening ring are both provided with matching square grooves. The square groove on the fingertip sleeve is a blind square groove with the opening facing backward, and the square groove on the opening ring is a through square groove that runs from front to back. The fixing spring plate passes through each square groove, and the fixing spring plate slides freely in the through square groove, with one end of the fixing spring plate fixed in the blind square groove.

[0012] Furthermore, the bottom of the fingertip sleeve is provided with a through hole I, and the bottom of the open ring is provided with a through hole II. One end of the drive rope passes through through hole II and through hole I in sequence, and is connected to the core wire of the Bowden wire together with the other end of the drive rope. When in use, the drive rope fits against the fingertip.

[0013] Furthermore, a hand support seat is provided on the bottom surface of the hand mounting block.

[0014] The hand support block fits snugly to the human hand, preventing patients from exerting force.

[0015] Furthermore, a Bowden wire fixing block is provided at the bottom of the palm mounting block. After the Bowden wire is interference-fitted into the groove of the Bowden wire fixing block, the Bowden wire fixing block is inverted and fixed on the bottom surface of the palm mounting block to fix the Bowden wire.

[0016] Furthermore, a notch is provided on one side of the palm mounting block to make the cross-sectional shape of the palm mounting block U-shaped so that the palm can be placed into the palm mounting block.

[0017] Furthermore, the variable stiffness drive module includes a micro motor mounted on the top surface of the palm mounting block, a gear connected to the shaft of the micro motor, and a rack meshing with and sliding within the guide rail assembly, the rack being connected to a sliding spring plate.

[0018] Compared with the prior art, the advantages of the present invention are: By using a micro motor to drive a gear and rack structure to extend and retract a sliding spring plate, the thickness of the spring plate on the back of the finger can be changed, enabling continuous and precise adjustment of the simulated stiffness of the finger extensor muscles. The control module can precisely control the speed and angle of the micro motor to meet the stiffness requirements of different rehabilitation stages.

[0019] Although the variable stiffness driven micro motor is installed in the palm of the hand, it is small in size, light in weight, and has no extra redundant structure, resulting in very low hand load.

[0020] Furthermore, the guide rail assembly includes a pair of rack guide rails I and rack guide rail II, which are fixed on the palm mounting block. The rack and sliding spring plate are slidably disposed between rack guide rails I and rack guide rail II.

[0021] The above description is merely an overview of the technical solution of the present invention. In order to better understand the technical means of the present invention and to implement it in accordance with the contents of the specification, and to make the purpose, features and advantages of the present invention more obvious and understandable, preferred embodiments are described below in detail with reference to the accompanying drawings. Attached Figure Description

[0022] Figure 1 This is an overall wearing example diagram of an embodiment of a line-driven variable stiffness hand function rehabilitation device according to the present invention; Figure 2a for Figure 1 Side view of the variable stiffness process; Figure 2b for Figure 1 A three-dimensional diagram of the variable stiffness process; Figure 2c , 2d These are the schematic diagram of the variable stiffness principle and its equivalent diagram; Figure 3a for Figure 1 A schematic diagram of the end face of the middle fingertip sleeve; Figure 3b for Figure 1 Side view of the middle fingertip sleeve; Figure 4 for Figure 1 Schematic diagram of the structure of the open-ended ring; Figure 5 for Figure 1 Schematic diagram of the middle palm mounting block; Figure 6a for Figure 1 Top view of the assembled medium stiffness component; Figure 6b for Figure 1 Schematic diagram of the end face of the medium stiffness variable component after assembly; Figure 6c for Figure 1 A three-dimensional schematic diagram of the assembled medium stiffness component; Figure 7a for Figure 1 Schematic diagram of the end face of the center guide rail assembly; Figure 7b for Figure 1 Top view of the center guide rail assembly; Figure 8a for Figure 1 Schematic diagram of the structure of the motor support block I; Figure 8b for Figure 1 Schematic diagram of the structure of the motor support block II; Figure 9a for Figure 1 Schematic diagram of the structure of the middle Boden line fixing block; Figure 9bfor Figure 1 A schematic diagram of the middle hand support base.

[0023] Figure label: 1-Fingertip sleeve, 101-Fingertip hole, 102-Blind square groove, 103-Threaded hole, 104-Through hole I; 2-Open ring, 21-Finger hole, 22-Square groove, 23-Wire hole II; 3-Fixed spring plate, 4-Sliding spring plate, 5-Rack and pinion guide rail I, 6-Rack and pinion guide rail II, 7-Rack, 8-Gear, 9-Micro motor, 10-Motor support block I, 11-Palm mounting block, 12-Motor support block II, 13-Drive rope, 14-Bowden wire fixing block, 15-Bowden wire, 16-Hand support seat, 17-Bowden wire drive module, 18-Control module. Detailed Implementation

[0024] 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 some embodiments of the present invention, and not all embodiments. 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.

[0025] An embodiment of the present invention provides a line-driven variable stiffness hand function rehabilitation device, such as... Figures 1 to 9b As shown, the device includes a finger actuation component, a palm mounting component, a variable stiffness drive component, a Bowden wire drive module, and a control module. The finger actuation component provides basic tension by simulating the extensor muscles on the back of the finger using a spring plate. The Bowden wire drive module achieves finger flexion via Bowden wire traction. The variable stiffness drive component uses a rack and pinion mechanism to extend and retract the spring plate, adjusting the simulated stiffness of the extensor muscles. The palm mounting component supports the palm. The control module 18 is connected to the variable stiffness drive component and the Bowden wire drive module, and outputs control signals to regulate the device's actions and stiffness parameters. The device is described with the fingertip as the front end during use. Figure 1 , Figure 2b These are all schematic diagrams simulating the placement of a hand.

[0026] The finger execution component includes a fingertip sleeve 1, an open ring 2, a fixing spring plate 3, and a drive rope 13. This invention provides four sets of finger execution components for rehabilitation training of all fingers except the thumb. The size of each finger execution component corresponds to the size of each finger. The following description uses one finger execution component as an example. Both the fingertip sleeve 1 and the open ring 2 are lightweight structures adapted to fit the human finger and can be worn at different positions on the finger. The fingertip sleeve 1 is used to fit the fingertip, and the open ring 2 is used to fit the entire finger. In this embodiment, five open rings 2 are provided on the same finger execution component, and in use, the five open rings 2 are sequentially fitted onto the finger. The fingertip sleeve 1 has a fingertip hole 101, the inner diameter of which gradually increases from front to back to facilitate fitting the fingertip. The open ring 2 has a finger hole 21, with an opening on one side. Both the fingertip sleeve 1 and the open ring 2 have matching square grooves. The square groove on the fingertip sleeve 1 is a blind square groove 102 with the opening facing backward, and the square groove on the open ring 2 is a through square groove 22 that runs from front to back. A fixing spring plate 3 passes through each square groove. One end of the fixing spring plate 3 is fixed to the fingertip sleeve 1, and the rest can slide freely in the through square groove 22 of the open ring 2. Specifically, the end of the fixing spring plate 3 is inserted into the blind square groove 102. The upper side wall of the fingertip sleeve 1 has a threaded hole 103 that passes through the blind square groove 102. A screw is used to pass through the through hole on the outside of the threaded hole 103 and then through the through hole on the fixing spring plate 3 in the blind square groove 102, and then connects with the threaded hole on the inside of the threaded hole 103, thereby fixing the fixing spring plate 3 to the fingertip sleeve 1. The rest of the fixing spring plate 3 can slide back and forth in the through square groove 22 on each open ring 2. The fixed spring plate 3 is made of elastic steel plate, simulating the extensor muscles on the back of the human finger. During use, the fixed spring plate 3 is located on the back of the finger, providing basic tension to keep the finger open without traction. The fingertip sleeve 1 has a wire-passing hole I 104 at its bottom away from the blind square groove 12, and the open ring 2 has a wire-passing hole II 23 at its bottom away from the square groove 22. One end of the drive rope 13 passes sequentially through each wire-passing hole II 23 and wire-passing hole I 104, and together with the other end of the drive rope 13, connects to the core wire of the Bowden wire. During use, the drive rope 13 conforms to the fingertip, achieving a close-fitting arrangement for wire traction.

[0027] In this embodiment, both the fingertip sleeve 1 and the open ring 2 are made of lightweight soft material, possessing a certain degree of elastic deformation capability to adapt to different finger thicknesses. The square groove dimensions of the fingertip sleeve 1 and the open ring 2 are adapted to the fixed spring plate 3, ensuring that the fixed spring plate 3 is inserted in place and slides smoothly. The material of the fixed spring plate 3 is 65Mn elastic steel plate. The diameter of the through hole (including through hole I 104 and through hole II 23) is adapted to the drive rope 13. The drive rope 13 is passed through the through hole, and both ends of the drive rope 13 are fixedly connected to the core wire at one end of the Bowden wire 15 to ensure effective transmission of traction force. In use, the hand first passes through the palm mounting block 11, and each finger passes through the open ring 2 and the fingertip sleeve 1 in the corresponding finger actuator component in sequence, making it simple and convenient to wear.

[0028] By sliding the open ring 2 against the fixed spring plate 3, the position of the open ring 2 can be adjusted according to the length of the patient's fingers.

[0029] The hand mounting assembly includes a hand mounting block 11, a Bowden wire fixing block 14, and a hand support base 16. The hand is worn inside the hand mounting block 11, which has a through cavity. After the hand passes through the hand mounting block 11, the fingers can be inserted into the finger actuator. A variable stiffness drive component is provided on the outer side of the hand mounting block 11 near the back of the hand. The Bowden wire fixing block 14 secures the Bowden wire sleeve on the outer side of the hand mounting block 11 near the palm, placing the Bowden wire at the bottom of the hand mounting block 11 to prevent tangling and ensure smooth wire-driven traction. The hand support base 16 is provided on the outer side of the hand mounting block 11 near the palm. Placing the hand support base 16 on a tabletop supports the hand and prevents the hand from exerting force.

[0030] In this embodiment, the mounting positions on the surface of the palm mounting block 11 are standardized bolt holes. The bolt holes on the top of the palm mounting block 11 (near the back of the hand) can be adapted to the gear guide rail of the variable stiffness drive assembly, and the gear guide rail can be fixed to the palm mounting block 11 by bolts to ensure a firm connection. The bolt holes on the bottom of the palm mounting block 11 (near the palm) are fixed to the Bowden wire fixing block 14 by bolts. The Bowden wire fixing block 14 is generally Z-shaped. The Bowden wire is interference-fitted into the groove of the Bowden wire fixing block 14, and then the Bowden wire fixing block 14 is upside down on the bottom surface of the palm mounting block 11 and fixed with bolts. The hand support base 16 can be fixed to the palm mounting block 11 by bolts, and then placed on a table to support the hand for rehabilitation work.

[0031] In this embodiment, a notch is provided on one side of the palm mounting block 11, making the cross-sectional shape of the palm mounting block 11 U-shaped, which facilitates the insertion of the palm into the palm mounting block 11, and the thumb can extend out from the notch to ensure free movement. The device of the present invention can be arranged in pairs, with the palm mounting component, variable stiffness drive component, and finger actuation component of the paired device arranged symmetrically.

[0032] The variable stiffness drive assembly includes a sliding spring plate 4, rack guide rail I 5, rack guide rail II 6, rack 7, gear 8, micro motor 9, and motor support block. The number of variable stiffness drive assemblies is equal to the number of finger actuation assemblies, and they correspond one-to-one in the front-rear direction. The dimensions of the sliding spring plate 4 and rack 7 in each variable stiffness drive assembly correspond to the dimensions of the corresponding finger actuation assembly, ensuring that the sliding spring plate 4 can match the corresponding fixed spring plate 3. The positions of the gear 8 and micro motor 9 are set according to the dimensions of the rack 7. An example is given below. The motor support block can be set as a corresponding motor support block I 10 or motor support block II 12 in different variable stiffness drive assemblies, such as... Figure 8a , Figure 8b As shown, the motor support block has bolt holes for fixing to the palm mounting block 11 and bolt holes for fixing to the micro motor 9. The difference between motor support block I 10 and motor support block II 12 is that the structure containing the bolt holes for fixing to the micro motor 9 on motor support block I 10 is detachably mounted on motor support block I 10, while the structure containing the bolt holes on motor support block II 12 is integrally mounted. The motor support block is bolted to the palm mounting block 11, and the micro motor 9 is bolted to the corresponding motor support block. Rack guide rail I 5 and rack guide rail II 6 are arranged in pairs to form a guide rail assembly, such as... Figure 7a , Figure 7b As shown, rack guide rails I5 and II6 are both fixed to the palm mounting block 11 by bolts. The rack 7 is positioned between rack guide rails I5 and II6 and can slide back and forth between them. Gear 8 is directly connected to the shaft of the micro motor 9. The micro motor 9 is mounted on the palm mounting block 11 via a corresponding motor support block. Gear 8 meshes with the rack 7. The motor support block is located on one side of the guide rail assembly to support and fix the micro motor 9. Gaps are left between adjacent guide rail assemblies to accommodate the corresponding motor support blocks.

[0033] The sliding spring plate 4 is bolted to the rack 7 on the side closest to the finger during use. When the micro motor 9 rotates forward, the rack 7 extends the sliding spring plate 4 towards the finger. The sliding spring plate 4 pushes against the fixed spring plate 3 and passes through the square groove on the open ring 2 and the fingertip sleeve 1, increasing the thickness of the spring plate on the back of the finger. That is, the thickness of the spring plate is increased by the thickness of the sliding spring plate 4 on top of the thickness of the fixed spring plate 3. When the micro motor 9 rotates in reverse, the rack 7 retracts the sliding spring plate 4 along the square groove of the open ring 2 and the fingertip sleeve 1 towards the wrist, reducing the thickness of the spring plate on the back of the finger. The guide rail assembly not only guides the forward and backward sliding of the rack 7 but also guides the sliding of the sliding spring plate 4.

[0034] Both the fixed spring plate 3 and the sliding spring plate 4 are elastic steel plates, possessing suitable rigidity and elasticity to simulate the mechanical characteristics of the extensor muscles of the human finger. This device equates the spring plate on the back of the finger to a cantilever beam structure. Both beams (fixed spring plate 3 and sliding spring plate 4, respectively) are fixed only at one end, and the two beams are attached vertically but not bonded together. The stiffness can be adjusted by changing the extension length of the lower beam (sliding spring plate 4). The schematic diagram and its equivalent diagram are shown below. Figure 2c , 2d As shown, the thicknesses of the upper beam (fixed spring plate 3) and the lower beam (sliding spring plate 4) are h1 and h2 respectively, and their widths are both b. They are made of the same material with an elastic modulus of E. The length L of the upper beam remains constant, while the length of the lower beam is... It can be changed, and Because the overall beam bending angle is large, the small deformation assumption no longer holds, and the beam member is modeled based on the large deformation assumption. The beam undergoes significant large deformation under load, so the entire beam is divided into 32 elements, and a following local coordinate system (rotating coordinate system) is established at each node: The MCP joint region is divided into 10 units: ; Take one unit for the transition segment between the MCP and PIP joints: ; The PIP joint region is divided into 10 units: ; The DIP joint region is divided into 10 units: ; Take one unit from the tip of your finger. .in It is the length of each unit. .

[0035] make .

[0036] No. The unit in the first Deformation vector in a local coordinate system Load vector Position vector The rotation matrix between coordinate systems is: Cumulative turning angle .

[0037] Single beam segment: The cross-sectional area and moment of inertia of the upper beam are respectively The cross-sectional area and moment of inertia of the lower beam are respectively .

[0038] The lower beam extends from the left end and remains in contact with the upper beam throughout. The moment of inertia of the overlapping section is: Then the overlap length between the lower beam and the upper beam is Time The overlap length between the upper and lower beams within each unit is: Coverage ratio: Therefore, the first Units: Treating each element as a cantilever beam attached to the previous element, and combining this with Euler-Bernoulli beam theory, we obtain the... The unit in the first Stiffness matrix in local coordinate systems: Force Pulling the drive rope causes the fingers wearing the exoskeleton to bend, and the equivalent load on the spring plate is equivalent to a follow-up load that is always perpendicular to the end of the spring plate. The end-effector concentrated force is expressed in the global coordinate system as: Therefore, the first The unit in the first External load vector in a local coordinate system .make ,so Since the load acts at the end and there is no additional end moment, the end moment is... For the first Nodes .

[0039] The local equilibrium relationship of the element is as follows: Therefore, the first The unit in the first The deformation vector in each local coordinate system is: Joint angle: When the coincident length of the fixed spring plate and the sliding spring plate When the thickness increases, the overlapping area is equivalent to changing from a single-layer spring plate to a double-layer spring plate that jointly bears the bending force. As the length of the overlap between the fixed spring plate and the sliding spring plate increases, the equivalent bending stiffness of the overlapping region also increases; When decreasing, As the size of the sliding spring plate decreases, the area of ​​the single-layer spring plate increases, resulting in a reduction in the overall equivalent bending stiffness. Therefore, by adjusting the position of the sliding spring plate relative to the fixed spring plate, the local bending stiffness and overall bending stiffness of the spring plate assembly along the dorsal side of the finger can be altered.

[0040] The drive cord is positioned on the palmar side of the fingers or below the exoskeleton. When the drive cord is under tension, it causes the exoskeleton and fingers to flex. Due to the different overlap lengths of the fixed and sliding spring plates, the local bending resistance of the spring plate assembly near the MCP, PIP, and DIP joints varies, thus altering the distribution of rotational angles at each joint under the same driving force. As the overlap length increases, the resistance of the spring plate assembly to finger flexion increases, resulting in a different joint bending angle under the same driving force. As the overlapping area between the sliding spring plate and the fixed spring plate increases, the corresponding length decreases; when the overlapping length decreases, the resistance of the spring plate assembly to finger flexion decreases, and the joint flexion angle under the same driving force decreases. The size increases accordingly as the overlapping area between the sliding spring plate and the fixed spring plate increases.

[0041] Therefore, this invention achieves continuous or graded adjustment of the elastic support stiffness on the dorsal side of the finger exoskeleton by adjusting the overlap length of the fixed spring plate and the sliding spring plate with a slider, thereby adapting to the needs of different patients, different rehabilitation stages and different training intensities for finger flexion resistance and motor assistance.

[0042] When the micro motor 9 rotates forward, the gear 8 connected to it rotates forward, causing the sliding spring plate 4 connected to the rack 7 to extend along the square groove of the open ring 2, increasing the thickness of the spring plate on the back of the finger and increasing the simulated stiffness of the finger actuation component; when the micro motor 9 rotates in reverse, the gear 8 connected to it rotates in reverse, causing the sliding spring plate 4 connected to the rack 7 to retract along the square groove of the open ring 2, decreasing the thickness of the spring plate on the back of the finger and decreasing the simulated stiffness of the finger actuation component.

[0043] With the plate width and material remaining constant, changing the extension length of the lower beam can achieve a change in overall stiffness. For the same finger bending angle, greater stiffness requires a larger linear drive force.

[0044] Bowden wire drive module 17 is located outside the device and is connected to the end of Bowden wire 15 away from drive rope 13 to realize weightless wire drive traction of the hand. Bowden wire 15 is fixed to drive rope 13 after passing through the wire groove of palm mounting block 11. Bowden wire drive module 17 pulls Bowden wire 15 to drive drive rope 13 to pull finger actuator, thereby pulling the finger to realize bending action and ensure the naturalness of the action.

[0045] In this embodiment, the Bowden line drive device 17 adopts an external electric traction structure, which can adjust the traction force and traction frequency. The Bowden line 15 is made of wear-resistant flexible Bowden line, which is fixed to the lower part of the palm mounting block 11 and connected one-to-one with the drive rope 13 to ensure independent traction of a single finger. The drive rope 13 is made of flexible nylon rope.

[0046] When the finger is bent online, the fingertip sleeve 1 and the open ring 2 are put on the finger. The external Bowden line drive module 17 pulls the Bowden line 15, and applies tension to the finger through the drive rope 13 to overcome the elastic force of the extensor muscle simulation structure (i.e., the cantilever beam structure), so that the finger can complete the bending action.

[0047] When the finger is reset, when the Bowden wire drive module 17 releases the traction force on the Bowden wire 15, the fixed spring plate 3, under the action of its own elastic restoring force, pulls the finger back to the open state, completing one finger flexion and extension rehabilitation training; throughout the training process, the control module 18 can adjust the stiffness parameters of the variable stiffness drive component and the traction parameters of the Bowden wire drive module 17 in real time according to the training feedback, so as to achieve dynamic adaptation.

[0048] In this embodiment, the control module 18 uses an STM32 microcontroller and is connected to the micro motor 9 and Bowden wire drive device 17 via wires. It can output control signals to adjust the speed and angle of the micro motor 9, as well as the traction force and length of the Bowden wire drive module 17, thereby controlling the extension length of the sliding spring plate 4 to achieve variable stiffness. This controls the bending degree of the finger actuator and the sliding spring plate 4, realizing coordinated control of variable stiffness drive and wire drive traction. Simultaneously, rehabilitation training parameters can be preset to meet personalized training needs. The wires of the micro motor 9 are led out through the palm mounting block 11 and connected to the control module 18.

[0049] Compared with the prior art, the present invention has the following advantages: 1) Precise and continuous stiffness adjustment: The micro motor 9 drives the gear and rack structure to move the sliding spring plate 4, changing the thickness of the spring plate on the back of the finger, so as to realize the continuous and precise adjustment of the simulated stiffness of the finger extensor muscles. The control module 18 can precisely control the speed and angle of the micro motor 9 to meet the stiffness requirements of different rehabilitation stages.

[0050] 2) Easy to wear and low weight: The palm mounting block 11 with support and the lightweight finger actuator are worn in a way that fits the human hand. The Bowden wire drive module 17 is located outside the device, so the weight is not applied to the palm. Although the variable stiffness driven micro motor 9 is installed in the palm, it is small in size and light in weight, and there is no extra redundant structure, so the hand load is extremely low. The external traction design of the Bowden wire further ensures the naturalness of finger flexion and extension movements.

[0051] 3) Coordinated matching of line drive and variable stiffness: The control module 18 can realize the coordinated control of the variable stiffness drive component and the Bowden line drive module 17. The stiffness adjustment is precisely matched with the traction force and frequency of finger flexion and extension, which can simulate the natural mechanical characteristics of human finger flexion and extension and improve the rehabilitation training effect.

[0052] The line-driven variable stiffness hand function rehabilitation device of the present invention, through the synergistic design of line drive and variable stiffness structure, can simulate the mechanical characteristics of human finger flexion and extension, realize the weightless traction of finger flexion and extension and the dynamic control of extensor muscle simulated stiffness, adapt to the personalized training needs of patients at different rehabilitation stages, and is suitable for rehabilitation training of patients with different degrees of hand motor dysfunction. The structure is lightweight and easy to wear, and can be widely used in rehabilitation medical institutions and home rehabilitation training scenarios.

[0053] In other embodiments, improvements can be made based on the above embodiments. The variable stiffness drive module, such as the micro motor 9, gear 8, rack 7, etc., used to drive the sliding spring plate 4 to slide, can be replaced with a variable stiffness drive module such as a hydraulic cylinder, pneumatic cylinder, or linear motor. One end of the sliding spring plate 4 is connected to the output end of the hydraulic cylinder or pneumatic cylinder. The extension and retraction of the hydraulic cylinder or pneumatic cylinder can be controlled by the control module, thereby controlling the extension and retraction of the sliding spring plate 4.

[0054] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A line-driven variable stiffness hand function rehabilitation device, comprising a hand mounting block (11) for fitting onto the palm and a control module (18), characterized in that: The front side of the palm mounting block (11) is provided with a finger execution component corresponding to the finger, and the top surface is provided with a variable stiffness drive component corresponding to the finger execution component. The finger execution component includes a fingertip sleeve (1) that is fitted onto the fingertip, several open rings (2) distributed on the finger, a fixed spring plate (3) with one end fixed to the top of the fingertip sleeve (1) and the rest sliding through the top of the open ring (2), and a drive rope (13) connected to the bottom of the fingertip sleeve (1) and the open ring (2). The variable stiffness drive component includes a variable stiffness drive module fixedly installed on the top surface of the palm mounting block (11) and a variable stiffness drive module. The drive module is connected to a sliding spring plate (4) for telescopic movement, and a guide rail assembly is fixedly installed on the top surface of the palm mounting block (11) to guide the sliding spring plate (4) to slide. The sliding spring plate (4) can slide back and forth on the top of the open ring (2) and the fingertip sleeve (1). A Bowden wire (15) is fixedly installed on the bottom surface of the palm mounting block (11). The core wire of the Bowden wire (15) is connected to the drive rope (13). The other end of the Bowden wire (15) is connected to the Bowden wire drive module (17). The variable stiffness drive module, the Bowden wire drive module (17) and the control module (18) are connected.

2. The linearly driven variable stiffness hand function rehabilitation device according to claim 1, characterized in that: The top of the fingertip sleeve (1) and the open ring (2) are both provided with matching square grooves. The square groove on the fingertip sleeve (1) is a blind square groove (102) with the opening facing backward, and the square groove on the open ring (2) is a through square groove (22) that runs from front to back. The fixed spring plate (3) runs through each square groove. The fixed spring plate (3) slides freely in the through square groove (22) and one end of the fixed spring plate (3) is fixed in the blind square groove (102).

3. The linearly driven variable stiffness hand function rehabilitation device according to claim 1, characterized in that: The bottom of the fingertip sleeve (1) is provided with a through hole I (104), and the bottom of the open ring (2) is provided with a through hole II (23). One end of the drive rope (13) passes through the through hole I (104) and the through hole II (23), and together with the other end of the drive rope (13), it is connected to the core wire of the Bowden wire (15). When in use, the drive rope (13) fits against the fingertip.

4. The linearly driven variable stiffness hand function rehabilitation device according to claim 1, characterized in that: A hand support seat (16) is provided on the bottom surface of the palm mounting block (11).

5. The linearly driven variable stiffness hand function rehabilitation device according to claim 1, characterized in that: A Bowden wire fixing block (14) is provided at the bottom of the palm mounting block (11). After the Bowden wire (15) is interference-fitted into the groove of the Bowden wire fixing block (14), the Bowden wire fixing block (14) is upside down on the bottom surface of the palm mounting block (11) and fixed to achieve the fixation of the Bowden wire (15).

6. The linearly driven variable stiffness hand function rehabilitation device according to claim 1, characterized in that: A notch is provided on one side of the palm mounting block (11) so that the cross-sectional shape of the palm mounting block (11) is U-shaped so that the palm can be placed into the palm mounting block (11).

7. The linearly driven variable stiffness hand function rehabilitation device according to claim 1, characterized in that: The variable stiffness drive module includes a micro motor (9) set on the top surface of the palm mounting block (11), a gear (8) connected to the shaft of the micro motor (9), and a rack (7) meshing with and sliding in the guide rail assembly. The rack (7) is connected to the sliding spring plate (4).

8. The linearly driven variable stiffness hand function rehabilitation device according to claim 1, characterized in that: The guide rail assembly includes a pair of rack guide rails I (5) and rack guide rail II (6). The rack guide rails I (5) and rack guide rail II (6) are fixed on the palm mounting block (11). The rack (7) and the sliding spring plate (4) are slidably arranged between the rack guide rails I (5) and rack guide rail II (6).

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