Bionic coupling dynamic adjustable ankle foot orthosis and biomechanical regulation and control method thereof

Abstract

The invention discloses a bionic coupling dynamic adjustable ankle foot orthosis and a biomechanical regulation and control method thereof, and relates to the technical field of rehabilitation medical instruments. Comprising an energy storage and release assembly, the upper end of the energy storage and release assembly is fixedly connected with an upper fixedly-connected shell, and when a wearer walks, gait adjustment is dynamically assisted through circulation of energy storage when the heel touches the ground and energy release when the tiptoe touches the ground; the rotary link shell is detachably connected with the lower end of the energy storage and release assembly; the adjusting piece group is arranged in the rotary linking shell; the connecting strip-shaped plate piece is connected with the adjusting piece set; the energy storage and release assembly can sense the gait phase in real time by means of the phase change characteristic of a memory alloy spring through a combined structure of the memory alloy spring and a winding tubular support, energy is accurately stored when the heel of a wearer touches the ground, energy is stably released when the tiptoe touches the ground, and dynamic adjustment of the orthosis is achieved; energy recovery and auxiliary driving dynamic coupling in the gait cycle can be completed, physical output of a wearer during walking is effectively reduced, and the dynamic requirement of natural gaits of the human body is met.

Description

Technical Field

[0001] This invention relates to the field of rehabilitation medical device technology, specifically to a biomimetic coupled dynamic adjustable ankle-foot orthosis and its biomechanical control method. Background Technology

[0002] Ankle-foot orthoses are key assistive devices in the rehabilitation process of patients with lower limb dysfunction. Their core function is to correct abnormal ankle postures, improve gait stability, and reduce the load on the ankle joint and surrounding joints during walking through external mechanical support structures, thus providing necessary assistance for the recovery of gait function.

[0003] With the deepening of rehabilitation medicine concepts and the upgrading of clinical needs, traditional ankle-foot orthoses have gradually revealed many technical limitations in practical applications, making it difficult to meet patients' needs for dynamic rehabilitation and daily use. Specific problems are as follows:

[0004] 1. Traditional orthoses often employ a fixed, rigid structure design, providing only static support in a single mode and failing to respond to the dynamic changes in the ankle joint during the gait cycle. In dynamic movement scenarios (such as walking and climbing stairs), patients often experience gait stiffness and decreased motor coordination due to excessive restriction of the ankle joint's range of motion, directly impacting the effectiveness of rehabilitation training. Furthermore, prolonged immobilization may even lead to secondary injuries such as muscle atrophy and joint adhesions.

[0005] 2. Because different areas of the sole (forefoot, arch, and heel) experience significant differences in pressure during the gait cycle, traditional designs cannot achieve a balanced pressure distribution. After prolonged use, patients are prone to excessive local pressure on the sole, which can lead to foot fatigue, pain, and in severe cases, even pressure sores, affecting the continuity of treatment.

[0006] 3. While some existing technologies incorporate biomimetic concepts, they often focus on single functional modules without considering the overall biomechanical characteristics of the ankle and foot system for synergistic optimization. For example, they cannot simulate the dynamic process of "energy storage and release" in the Achilles tendon during gait in a normal human body, resulting in low energy utilization of the orthosis. This requires patients to expend more energy when walking, increasing the burden of daily use.

[0007] 4. Traditional orthotics generally suffer from a noticeably mechanical appearance and poor breathability of materials. On the one hand, the cold, mechanical structure can easily trigger psychological resistance in patients (especially children and young patients); on the other hand, the non-breathable material design leads to stuffiness and sweat accumulation in the feet during wear, resulting in poor comfort. Furthermore, most orthotics are not adjustable, making it difficult to fit different patients' leg circumferences and foot sizes, further reducing patients' willingness to wear them and affecting adherence to and effectiveness of rehabilitation treatment. Summary of the Invention

[0008] The purpose of this invention is to provide a biomimetic coupled dynamic adjustable ankle-foot orthosis and its biomechanical control method. By designing a biomimetic joint range-of-motion mechanism, a gradient modulus footpad, and a human-computer interaction structure, the orthosis can adapt to dynamic movements and limit the range of motion of the joints, while achieving a balanced distribution of plantar pressure and improving user compliance.

[0009] To achieve the above objectives, the technical solution of this application is: a biomimetic coupled dynamically adjustable ankle-foot orthosis, comprising:

[0010] The upper breathable elastic support strap is detachably connected to the leg support.

[0011] The upper fixed connection shell is fixedly connected to the leg support;

[0012] The energy storage and release component is fixedly connected to the upper fixed connection shell. When the wearer walks, it dynamically assists in adjusting the gait by storing energy when the heel hits the ground and releasing energy when the toes hit the ground.

[0013] The rotating connecting housing is detachably connected to the lower end of the energy storage and release component;

[0014] The adjusting assembly is built into the rotary link housing;

[0015] Connecting strip-shaped plates, which are connected to the adjusting assembly;

[0016] The lower soft foot is covered with a bandage, located on the footrest, and is detachably connected to the connecting strip plate;

[0017] The biomimetic cushioning pad is located inside the footrest, and the bottom of the footrest has anti-slip texture.

[0018] In a preferred embodiment of the present invention, the energy storage and release component comprises a shape memory alloy spring and a support tube wound around the spring, wherein the phase transition temperature of the shape memory alloy spring is 28℃±2℃ and the stored energy density is ≥0.8J / cm³. 3 It provides 15-30N of thrust when releasing energy.

[0019] As a preferred embodiment of the present invention, the adjusting component assembly includes a rotating shaft and a sliding screw. A sliding groove is provided on the corresponding rotating connecting housing. By cooperating with the sliding screw and the sliding groove, the dorsiflexion angle of the ankle joint is limited to 0-15° and the plantarflexion angle is limited to 0-30°. The sliding groove has millimeter-level graduations, with each graduation corresponding to a 1.5° angle adjustment.

[0020] As a preferred embodiment of the present invention, the biomimetic cushioning pad is designed to resemble the paw pads of a domestic cat; the modulus of the biomimetic cushioning pad is gradient-distributed along the arch direction, with 8±2MPa in the forefoot area, 3±0.5MPa in the arch area, and 6±1MPa in the heel area; the porosity is zoned, with 30±5% in the forefoot area, 65±8% in the arch area, and 40±5% in the heel area.

[0021] In a preferred embodiment of the present invention, the sliding groove is formed on the arc-shaped plate, the arc-shaped plate is located on the inner wall of the housing of the adjusting component assembly, the housing of the adjusting component assembly is fixed on the rotating link housing, and a limiting screw is provided on the inner side of the arc-shaped plate, the limiting screw being located on both sides of the connecting strip plate.

[0022] As a preferred embodiment of the present invention, the support tube and the rotating connecting housing are connected by a quick-release interface, and the surface of the leg support is provided with a pressure-sensing film.

[0023] This invention also provides a biomechanical control method for a biomimetic coupled dynamically adjustable ankle-foot orthosis, comprising:

[0024] Dynamic force field matching steps:

[0025] a) Gait phase is detected in real time by a heel pressure sensor, and heel strike is determined when the pressure threshold exceeds a preset threshold;

[0026] b) Trigger the compression and energy storage of the shape memory alloy spring;

[0027] c) Maintain potential energy during the transition period of the center of gravity;

[0028] d) Detect changes in Achilles tendon tension to determine when the toes leave the ground, releasing spring potential energy to provide 15-30N of propulsive force;

[0029] Foot pressure optimization steps:

[0030] e) Obtain the optimal modulus distribution based on the plantar pressure model;

[0031] f) Manufacturing partitioned porous structure footpads using 3D printing;

[0032] Joint protection steps:

[0033] g) In the standing phase, the sliding screw is locked in the P1 slot of the sliding groove to limit backbend;

[0034] h) Move the sliding screw to the P3 slot to release the plantar flexion degree of freedom.

[0035] As a preferred embodiment of the present invention, there is a delay compensation of 50-200ms between the energy storage trigger in step b) and the energy release trigger in step d), which is used to filter out abnormal gait fluctuations.

[0036] As a preferred embodiment of the present invention, the plantar pressure model is as follows:

[0037]

[0038] k1 and k2 are weighting coefficients used to balance the Gaussian distribution term based on the heel pressure center and the integral term based on the gradient modulus of the arch direction; x0 is the coordinate of the heel pressure center; σ x The standard deviation of the lateral pressure distribution on the sole of the foot; G(ξ) is a Gaussian function used to describe the distribution of lateral plantar pressure with the heel pressure center as the core; G(ξ) is the gradient modulus function along the arch direction, where ξ is the integral variable along the arch direction. This involves integrating the gradient modulus along the arch direction from the starting point to position y to reflect the influence of the change in modulus along the arch direction on plantar pressure.

[0039] As a preferred embodiment of the present invention, the backbend limiting angle is determined by the formula θ_b = 15° - β·s. 2 The values ​​are dynamically obtained, where θ_b is the actual backbend limit angle (in degrees), β is the gait adaptation coefficient, β∈[0.02,0.05], and s is the displacement of the sliding screw.

[0040] By adopting the above technical solution, the present invention can achieve the following technical effects:

[0041] 1. By combining the shape memory alloy spring with the support tube, the phase change characteristics of the shape memory alloy spring can be used to sense the gait phase in real time. It can accurately store energy when the wearer's heel strikes the ground and stably release energy when the toes strike the ground. This not only enables the orthosis to be dynamically adjustable, but also completes the dynamic coupling of energy recovery and auxiliary drive in the gait cycle, effectively reducing the wearer's physical exertion when walking and adapting to the dynamic needs of the human body's natural gait.

[0042] 2. Relying on the adjustable rotating connecting shell and internal adjustment components, it can specifically limit the dorsiflexion and plantarflexion angles of the wearer's ankle joint, ensure the coordinated coupling of multiple force fields in the walking gait, avoid joint damage caused by abnormal range of motion, and significantly improve the stability and safety of the wearer during walking.

[0043] 3. The footrest features an elastic gradient structure designed to mimic the paw pads of a domestic cat, which evenly distributes pressure on the soles of the feet, effectively relieving foot fatigue and preventing joint damage. At the same time, the bottom of the footrest uses a cat paw-like anti-slip texture to further optimize the ergonomic experience, enhance ground friction when walking, and reduce the risk of slipping.

[0044] 4. The design of the upper and lower two breathable soft straps can improve the gait stability of the wearer while walking, and also has good breathability and fit, reducing stuffiness and discomfort during wear, greatly improving the user experience, thereby increasing the user's compliance with long-term wear and ensuring the rehabilitation assistance effect. Attached Figure Description

[0045] To more clearly illustrate the technical solutions in the embodiments of this application, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0046] Figure 1 This is a schematic diagram of a biomimetic coupled dynamic adjustable ankle-foot orthosis.

[0047] Figure 2 A partial schematic diagram of a biomimetic coupled dynamic adjustable ankle-foot orthosis;

[0048] Figure 3 A schematic diagram of the anti-slip texture and biomimetic cushioning pad structure;

[0049] Figure 4 This is a schematic diagram of the principle of a biomimetic coupled dynamic adjustable ankle-foot orthosis.

[0050] Figure 5 A flowchart illustrating the biomechanical control method for a biomimetic coupled dynamically adjustable ankle-foot orthosis.

[0051] The numbers in the diagram are explained as follows: 1. Anti-slip texture; 2. Bionic cushioning pad; 3. Foot support; 4. Soft foot wrap below; 5. Rotating shaft; 6. Connecting strip plate; 7. Rotary link housing; 8. Adjustment assembly; 9. Memory alloy spring; 10. Support tube; 11. Upper fixed connection housing; 12. Upper breathable elastic fixing strap; 13. Leg support; 14. Limiting screw; 15. Arc plate; 16. Sliding screw; 17. Sliding groove; 18. Fixing screw assembly; 19. Fixing sheet metal part. Detailed Implementation

[0052] It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0053] 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 some embodiments of the present invention, and not all embodiments. The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the present invention or its application or use. 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.

[0054] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of exemplary embodiments according to the invention. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0055] Unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps set forth in these embodiments do not limit the scope of the invention. It should also be understood that, for ease of description, the dimensions of the various parts shown in the drawings are not drawn to actual scale. Techniques, methods, and devices known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and devices should be considered part of the specification. In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters in the following figures denote similar items; therefore, once an item is defined in one figure, it need not be further discussed in subsequent figures.

[0056] In the description of this invention, it should be understood that the orientation or positional relationship indicated by directional terms such as "front, back, up, down, left, right", "horizontal, vertical, horizontal" and "top, bottom" is generally based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing this invention and simplifying the description. Unless otherwise stated, these directional terms do not indicate or imply that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on the scope of protection of this invention. The directional terms "inner" and "outer" refer to the inner and outer contours relative to the outline of each component itself.

[0057] For ease of description, spatial relative terms such as "above," "on top of," "on the upper surface of," "above," etc., are used herein to describe the spatial positional relationship of a device or feature as shown in the figures to other devices or features. It should be understood that spatial relative terms are intended to encompass different orientations in use or operation beyond the orientation of the device as described in the figures. For example, if the device in the figures were inverted, a device described as "above" or "on top of" other devices or structures would subsequently be positioned as "below" or "under" other devices or structures. Thus, the exemplary term "above" can include both "above" and "below." The device may also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatial relative descriptions used herein will be interpreted accordingly.

[0058] It should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to mechanical connections or electrical connections; they can refer to direct connections or indirect connections through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0059] Example 1:

[0060] like Figure 1-3 As shown, this embodiment provides a biomimetic coupled dynamic adjustable ankle-foot orthosis, including a dynamic force field generation module, a joint dynamic limiting module, a gradient pressure distribution module, and a breathable strap system.

[0061] The dynamic force field generation module includes a shape memory alloy spring 9 and a support tube 10. The phase transition temperature of the shape memory alloy spring is set to 28℃±2℃ to adapt to a temperature environment close to that of the human body surface for efficient operation. This module is configured such that during the wearer's walking gait, when the heel strikes the ground, the spring undergoes a phase transition under compression, converting mechanical energy into stored internal energy; when the gait enters the toe-off phase, the spring undergoes a reverse phase transition, releasing the stored internal energy as mechanical energy to provide propulsion assistance to the wearer. The support tube 10 not only provides winding support for the spring, but its lower end is also connected to the rotating link housing 7 via a standardized quick-release interface for easy disassembly and maintenance. To further improve adaptability, the inner surface of the leg support 13 also integrates an ultra-thin pressure-sensing film (not shown in the figure) for real-time monitoring of the pressure distribution applied to the calf.

[0062] The joint dynamic limiting module includes a rotating connecting housing 7 and an adjusting component assembly 8 encapsulated within it. The adjusting component assembly 8 mainly includes a rotating shaft 5, a connecting strip plate 6, a sliding screw 16, and a sliding groove 17 with millimeter-level graduations. Preferably, the sliding groove 17 is located on an arc-shaped plate 15, and a fixing sheet metal part 19 is fixed to the arc-shaped plate 15 by a fixing screw assembly for reinforcement. The limiting screw is located between the side wall of the arc-shaped plate and the side wall of the adjusting component assembly housing, used to reinforce the connecting strip plate and prevent its breakage. By moving the sliding screw 16 in the sliding groove 17, the range of motion of the ankle joint's dorsiflexion and plantarflexion can be limited. Each graduation corresponds to a 1.5° angle adjustment. This module is preset to limit the dorsiflexion angle to a maximum of 15° and the plantarflexion angle to a maximum of 30°, thereby ensuring effective coupling of multiple force fields during the gait cycle while preventing injury caused by excessive joint movement, significantly improving walking stability.

[0063] The core of the gradient pressure distribution module is the footrest 3 and its internal biomimetic cushioning pad 2. This cushioning pad is designed based on the paw pad structure of a domestic cat and is manufactured using SLS 3D printing technology. Its elastic modulus is not uniform but is designed with gradient variations according to the physiological weight-bearing characteristics of different areas of the human foot: the forefoot area has the highest modulus, set at 8±2MPa, to provide the support needed during push-off; the arch area has the lowest modulus, at 3±0.5MPa, to achieve good cushioning and deformation adaptation; the heel area has a moderate modulus, at 6±1MPa, to effectively absorb the impact force during heel strike. To achieve this gradient modulus, the porosity of the material in each area is also different: approximately 30±5% in the forefoot area, approximately 65±8% in the arch area, and approximately 40±5% in the heel area. This biomimetic design achieves a balanced distribution of foot pressure, effectively relieving foot fatigue and preventing joint damage. Furthermore, the bottom outer surface of the footrest 3 is designed with anti-slip texture 1 mimicking the pattern of a cat's paw pad, further enhancing stability and ergonomics during walking.

[0064] The breathable strap system is used to securely and comfortably fix the entire orthosis to the user's limb. It includes an upper breathable elastic fixation strap 12, an ergonomically designed leg support 13, and a lower soft foot wrap 4. The upper strap 12 and the leg support 13 are detachably connected via Velcro or snaps, allowing for quick adjustment according to the user's calf circumference and length. The lower foot wrap 4 is made of highly breathable mesh fabric, fully covering the user's foot and reliably connected to the foot support 3. While ensuring stable fixation, it greatly avoids stuffiness and discomfort in the feet during exercise, improving wearing comfort and user compliance.

[0065] This orthosis adopts a modular design concept. The main functional modules (such as the dynamic force field module, joint limiting module, and foot support module) are connected through standardized mechanical interfaces (such as quick-release interfaces and standard threaded connectors). This not only facilitates the wearing and removal of the device, but also supports rapid customized adjustments and replacements according to the individual needs of patients.

[0066] Example 2:

[0067] like Figure 4 As shown, a biomechanical regulation method based on the orthosis described in Example 1 is presented. This method achieves intelligent assistance and protection for the user's gait through the coordinated operation of various modules of the orthosis. The method mainly includes the following steps:

[0068] S1: Dynamic force field matching step, which aims to provide energy assistance at the appropriate time during the gait cycle.

[0069] a) Gait phase detection: A miniature pressure sensor integrated under the bionic cushioning pad 2 in the heel detects heel pressure in real time. When the detected pressure value exceeds a preset threshold (e.g., 20N), the control system determines that the gait has entered the "heel strike" phase.

[0070] b) Energy Storage Trigger: Once the heel strikes the ground, the shape memory alloy spring 9 begins to compress. Due to its unique phase change characteristics, the spring absorbs and stores energy during this process, with an energy storage density of ≥0.8 J / cm³. 3 .

[0071] c) Potential energy maintenance: During the transition of the center of gravity in the gait (i.e., the middle of the stance), the state of the spring is locked so that the stored potential energy is maintained.

[0072] d) Energy release trigger: The start of the "toe-off" phase is determined by a pressure sensor integrated into the forefoot or a miniature sensor (such as a strain gauge) used to monitor Achilles tendon tension. Once triggered, the shape memory alloy spring 9 rapidly releases its stored potential energy, providing approximately 15-30N of propulsive force to the ankle joint to assist in the push-off.

[0073] It should be noted that there is a programmable delay compensation of 50-200ms between the energy storage trigger (b) and the energy release trigger (d). This delay is used to filter out any abnormal minor fluctuations that may occur in the gait (such as pressure changes caused by slight unevenness of the ground), prevent false triggering, and ensure the accuracy and robustness of the movement.

[0074] S2: Plantar pressure optimization step, which optimizes the plantar pressure distribution from a static structural perspective through the gradient modulus design of the biomimetic cushioning pad 2.

[0075] e) Calculate the optimal modulus distribution: Based on the established mathematical model of the plantar pressure field, calculate and optimize the optimal modulus required for each region of the cushioning pad. This model can be expressed as:

[0076]

[0077] k1 and k2 are weighting coefficients used to balance the Gaussian distribution term based on the heel pressure center and the integral term based on the gradient modulus of the arch direction; x0 is the coordinate of the heel pressure center; σ x The standard deviation of the lateral pressure distribution on the sole of the foot; G(ξ) is a Gaussian function used to describe the distribution of lateral plantar pressure with the heel pressure center as the core; G(ξ) is the gradient modulus function along the arch direction, where ξ is the integral variable along the arch direction. This involves integrating the gradient modulus along the arch direction from the starting point to position y to reflect the influence of the change in modulus along the arch direction on plantar pressure. The gradient modulus function G(ξ) satisfies: G(ξ)=8-5·(ξ / L)[unit: MPa], where L is the total length of the arch direction from the heel to the forefoot, and ξ∈[0,L]. This function ensures a smooth transition of the modulus from the heel to the forefoot.

[0078] f) Manufacturing execution: Based on the obtained optimal modulus distribution parameters, selective laser sintering (SLS) 3D printing technology is used to manufacture a biomimetic buffer pad 2 with a partitioned pore structure by precisely controlling the laser power and scanning path, thereby achieving the gradient modulus required by the design.

[0079] S3: Joint protection step, which uses a joint dynamic limiting module to intelligently limit ankle joint range of motion at different stages of gait.

[0080] g) Standing Phase Limit: When the pressure sensor determines that the load-bearing phase has begun, the micro stepper motor (or manual adjustment followed by locking) moves and locks the sliding screw 16 into the P1 slot of the sliding groove 17. This position, based on a preset or dynamic calculation, limits the backbend angle to a safe range (e.g., 15°). The backbend limiting angle θ_b is not a completely fixed value and can be determined using the formula θ_b = 15° - β·s. 2 Dynamic fine-tuning is performed, which allows the limiting angle to be adjusted slightly adaptively according to the actual situation.

[0081] h) Swing phase release: When the swing phase (foot off the ground) is detected, the control sliding screw 16 moves to the P3 slot of the sliding groove 17. This position releases the restriction on the plantar flexion angle, allowing greater plantar flexion freedom, thereby avoiding unnecessary resistance to the joint during the swing leg and ensuring a natural and smooth gait.

[0082] In summary, the embodiments of the present invention, through the combination of biomimetic design and intelligent sensing control technology, provide an adjustable ankle-foot orthosis solution and its control method that not only provides dynamic power assistance but also optimizes pressure distribution, intelligently protects joints, and offers high comfort.

[0083] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application.

Claims

1. A biomimetic coupled dynamic adjustable ankle-foot orthosis, characterized in that, include: The upper breathable elastic support strap is detachably connected to the leg support. The upper fixed connection shell is fixedly connected to the leg support; The energy storage and release component is fixedly connected to the upper fixed connection shell. When the wearer walks, it dynamically assists in adjusting the gait by storing energy when the heel hits the ground and releasing energy when the toes hit the ground. The rotating connecting housing is detachably connected to the lower end of the energy storage and release component; The adjusting assembly is built into the rotary link housing; Connecting strip-shaped plates, which are connected to the adjusting assembly; The lower soft foot is covered with a bandage, located on the footrest, and is detachably connected to the connecting strip plate; The biomimetic cushioning pad is located inside the footrest, and the bottom of the footrest has anti-slip texture.

2. The biomimetic coupled dynamic adjustable ankle-foot orthosis according to claim 1, characterized in that, The energy storage and release component includes a shape memory alloy spring and a support tube wound around the spring. The phase transition temperature of the shape memory alloy spring is 28℃±2℃, and the stored energy density is ≥0.8J / cm³. 3 It provides 15-30N of thrust when releasing energy.

3. The biomimetic coupled dynamic adjustable ankle-foot orthosis according to claim 1, characterized in that, The adjustment assembly includes a rotating shaft and a sliding screw. A sliding groove is provided on the corresponding rotating link housing. By cooperating with the sliding screw and the sliding groove, the dorsiflexion angle of the ankle joint is limited to 0-15° and the plantarflexion angle is limited to 0-30°. The sliding groove has millimeter-level graduations, with each graduation corresponding to a 1.5° angle adjustment.

4. The biomimetic coupled dynamic adjustable ankle-foot orthosis according to claim 1, characterized in that, The biomimetic cushioning pad is designed to mimic the paw pads of a domestic cat. The modulus of the biomimetic cushioning pad is gradient-distributed along the arch direction, with 8±2MPa in the forefoot area, 3±0.5MPa in the arch area, and 6±1MPa in the heel area. The porosity is zoned, with 30±5% in the forefoot area, 65±8% in the arch area, and 40±5% in the heel area.

5. The biomimetic coupled dynamic adjustable ankle-foot orthosis according to claim 3, characterized in that, The sliding groove is formed on the arc-shaped plate, which is located on the inner wall of the housing of the adjusting component assembly. The housing of the adjusting component assembly is fixed on the rotating link housing. Limiting screws are provided on the inner side of the arc-shaped plate, and the limiting screws are located on both sides of the connecting strip plate.

6. The biomimetic coupled dynamic adjustable ankle-foot orthosis according to claim 2, characterized in that, The support tube is connected to the rotating connecting housing via a quick-release interface, and the surface of the leg support is provided with a pressure-sensitive diaphragm.

7. A biomechanical control method for a biomimetic coupled dynamically adjustable ankle-foot orthosis, characterized in that, include: Dynamic force field matching steps: a) Gait phase is detected in real time by a heel pressure sensor, and heel strike is determined when the pressure threshold exceeds a preset threshold; b) Trigger the compression and energy storage of the shape memory alloy spring; c) Maintain potential energy during the transition period of the center of gravity; d) Detect changes in Achilles tendon tension to determine when the toes leave the ground, releasing spring potential energy to provide 15-30N of propulsive force; Foot pressure optimization steps: e) Obtain the optimal modulus distribution based on the plantar pressure model; f) Manufacturing partitioned porous structure footpads using 3D printing; Joint protection steps: g) In the standing phase, the sliding screw is locked in the P1 slot of the sliding groove to limit backbend; h) Move the sliding screw to the P3 slot to release the plantar flexion degree of freedom.

8. The biomechanical control method for a biomimetic coupled dynamic adjustable ankle-foot orthosis according to claim 7, characterized in that, Furthermore, there is a 50-200ms delay compensation between the energy storage trigger in step b) and the energy release trigger in step d), which is used to filter out abnormal gait fluctuations.

9. The biomechanical control method for a biomimetic coupled dynamic adjustable ankle-foot orthosis according to claim 7, characterized in that, The plantar pressure model is as follows: k1 and k2 are weighting coefficients used to balance the Gaussian distribution term based on the heel pressure center and the integral term based on the gradient modulus of the arch direction; x0 is the coordinate of the heel pressure center; σ x The standard deviation of the lateral pressure distribution on the sole of the foot; G(ξ) is a Gaussian function used to describe the distribution of lateral plantar pressure with the heel pressure center as the core; G(ξ) is the gradient modulus function along the arch direction, where ξ is the integral variable along the arch direction. This involves integrating the gradient modulus along the arch direction from the starting point to position y to reflect the influence of the change in modulus along the arch direction on plantar pressure.

10. The biomechanical control method for a biomimetic coupled dynamic adjustable ankle-foot orthosis according to claim 7, characterized in that, Furthermore, the backbend limiting angle is determined by the formula θ_b = 15° - β·s. 2 The values ​​are dynamically obtained, where θ_b is the actual backbend limit angle (in degrees), β is the gait adaptation coefficient, β∈[0.02,0.05], and s is the displacement of the sliding screw.

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