Full degree of freedom lower limb bionic artificial limb

Abstract

The application provides a full-degree-of-freedom lower limb bionic artificial limb, which is used for solving the problem that it is difficult to simultaneously consider multi-structure cooperative linkage control, high bionic motion performance and long-term self-powered performance in the prior art. The full-degree-of-freedom lower limb bionic artificial limb comprises a foot plate, a supporting arm, an ankle assembly and a power generation assembly; the foot plate and the supporting arm are connected through the ankle assembly; the ankle assembly comprises a mounting plate, a turning shaft, a flexion and extension frame, a connecting arm and a power part which are vertically and fixedly connected in the supporting arm; the power part is configured to drive the turning shaft or the flexion and extension frame and the turning shaft to rotate cooperatively, so as to control the state of the foot plate to be one of plantar flexion, dorsal flexion, internal rotation, external rotation, internal collection or external expansion; the power generation assembly is configured on the supporting arm and is suitable for generating vibration of the power generation assembly in the process of walking with wind power and / or walking and storing the electric energy generated by the vibration of the power generation assembly in the power source. The artificial limb can realize high bionic motion through cooperative linkage control and long-term self-powered supply, and the endurance is improved.

Description

Technical Field

[0001] This invention belongs to the field of medical device prosthetics technology, and in particular relates to a fully free-degree-of-freedom lower limb bionic prosthesis. Background Technology

[0002] Lower limb prostheses are the core assistive devices for lower limb amputees to restore their walking ability, rebuild limb motor function, and return to normal life. With the rapid development of rehabilitation medicine and bionic mechanical technology, the market and patients have increasingly higher requirements for the bionicity, mobility, endurance, and environmental adaptability of lower limb prostheses.

[0003] Currently available lower limb prostheses are mostly rigid structures with single or few degrees of freedom. Their overall structural design is fixed, and their movement modes are limited, making it difficult to replicate the multi-dimensional movement characteristics of the human ankle and foot. In actual use, they can only achieve simple plantar flexion and dorsiflexion reciprocating movements, failing to perform the multi-dimensional bionic movements such as internal rotation, external rotation, adduction, and abduction necessary for normal walking, standing, turning, and climbing. This results in stiff walking posture and poor coordination for patients, and they are prone to uneven force distribution and center of gravity shift when walking on uneven or sloping surfaces. Not only is the bionic effect extremely poor, significantly reducing walking comfort, but it also greatly increases the risk of falls, failing to meet the diverse needs of patients for daily commuting, outdoor walking, and light exercise. At the same time, the drive structure of existing prostheses is mostly a single power output mode, unable to achieve multi-structure coordinated control, making it difficult to accurately switch various movement states of the foot, resulting in low posture adjustment accuracy and insufficient dynamic adaptability.

[0004] Furthermore, the current power supply method of prostheses relies heavily on external batteries for pre-stored power. The battery capacity is limited and the battery life is short. Patients need to frequently disassemble and recharge them, resulting in extremely poor usability. Moreover, in outdoor scenarios without charging, the power is easily depleted and the device stops working, causing the intelligent adjustment function of the prosthesis to fail or even become unusable. As a result, it is difficult to achieve continuous self-powered operation and cannot meet the current needs of amputees for high-performance, highly adaptable, long-lasting, and highly convenient lower limb prostheses. Summary of the Invention

[0005] In view of the shortcomings of the prior art described above, the purpose of this invention is to provide a fully free lower limb bionic prosthesis to solve the problem in the prior art of achieving high bionic motion performance and long-term autonomous power supply performance by simultaneously achieving multi-structure collaborative linkage control.

[0006] To achieve the above and other related objectives, the present invention provides a fully free-degree-of-freedom lower limb bionic prosthesis, comprising: Footboard, support arm, ankle assembly, and power generation assembly; The footplate and the support arm are connected via the ankle assembly; The ankle assembly includes a mounting plate, a flipping shaft, a flexion-extension frame, a connecting arm, and a power unit that are vertically and fixedly connected within the support arm; The two ends of the flipping shaft are rotatably connected to the mounting plate via mounting brackets, and a first bevel gear is provided on the flipping shaft; The extension frame is U-shaped. The two ends of the U-shaped opening of the extension frame are rotatably connected to the flipping shaft through bearings. A connecting hole is provided in the middle of the extension frame and facing the opening direction. The connecting arm is rotatably connected to the connecting hole through bearings. The upper end of the connecting arm has a second bevel gear that meshes with the first bevel gear, and the lower end is fixedly connected to the foot plate near the rear end. The power unit is configured to drive the flipping shaft or the flexor frame and the flipping shaft to rotate together, so as to control the foot state to be one of plantar flexion, dorsiflexion, internal rotation, external rotation, adduction or abduction; The power generation component is configured on the support arm and is adapted to generate vibrations in the presence of wind and / or during movement, and to store the electrical energy generated by the deformation caused by the vibrations in the power source.

[0007] Optionally, the power unit includes a first power source, a second power source, a first ring transmission unit, and a second ring transmission unit, wherein the first power source and the second power source are electrically connected to the power source. The ankle assembly is configured to have a first working state and a second working state; When in the first working state, the output power of the first power source is transmitted to the flipping shaft through the first ring transmission unit, so that the first bevel gear rotating with the flipping shaft drives the second bevel gear to rotate, thereby driving the connecting arm to move the foot plate to extend or retract. When in the second working state, the first power source and the second power source work together to transmit the output power to the flipping shaft and the flexion-extension frame through the first ring unit and the second ring transmission unit, respectively. The synergistic effect allows the foot plate to perform plantar flexion, dorsiflexion, internal rotation or external rotation.

[0008] Optionally, the power generation assembly includes a generating cylinder, a tube body, and a power generation section; The support arm is provided with a through hole extending from the front end to the rear end of the foot plate, and the through hole is located above the mounting plate; The generating cylinder is fixedly connected to the through hole, and has openings at both ends to form a hollow cavity, with the diameter of the middle section being larger than the diameter of the side sections at both ends; The tube is disposed inside the generating cylinder, and the outer wall of the tube and the inner wall of the hollow cavity of the generating cylinder form a vibration space; The power generation unit is configured inside the pipe body and is adapted to cause the pipe body to vibrate inside the generating cylinder when wind enters from one end of the pipe body and flows out from the other end, and / or during travel. The power generation unit performs vibration piezoelectric energy conversion and stores the electrical energy output in the power supply.

[0009] Optionally, the tube body is corrugated so that as the wind travels from one end of the tube body to the other, vortices are generated at the crests of the corrugations and then escape into the troughs, thereby increasing the power generation of the power generation unit through the generation and detachment of the corrugated structure and the fluid vortices.

[0010] Optionally, the power generation unit includes a flexible piezoelectric film, a first electrode, a second electrode, a first outer layer, and a second outer layer; The flexible piezoelectric film is disposed in the middle layer of the tube body, the first electrode and the second electrode are respectively located above and below the flexible piezoelectric film, and the first outer layer and the second outer layer are respectively located outside the first electrode and the second electrode; The power source is electrically connected to the first electrode and the second electrode.

[0011] Optionally, the flexible piezoelectric film material is made of one of aluminum nitride, zinc oxide, polyvinylidene fluoride (PVDF), and cadmium oxide (CdO). The first electrode is made of one of the following materials: aluminum, molybdenum, magnesium, and silver. The second electrode is made of one of the following materials: Cd, Pb, Ag, Al, Cu, Cr, and Au. The first outer layer and the second outer layer are made of flexible materials, which are polymeric organic plastics or polymeric organosilicon compounds.

[0012] Optionally, the power generation component further includes elastic parts, and multiple sets of elastic parts are provided between the outer walls of both ends of the tube and the inner wall of the generating cylinder, and the multiple elastic parts are arranged in a circumferential array along the central axis of the tube; The elastic part includes a relief cylinder, the central axis of which is perpendicular to the central axis of the generating cylinder. The relief cylinder is fixedly connected to the inner wall of the generating cylinder, and the relief cylinder is provided with a relief hole along its own axial direction. A sliding rod, which is perpendicular to the central axis of the tube and fixedly connected to the outer wall of the tube, is configured to slide axially along the clearance hole when an external force is applied; An elastic element is provided, which is adapted to reset the sliding rod from the inner wall of the generating cylinder toward the central axis of the tube.

[0013] Optionally, it also includes a center of gravity adjustment component, which includes a hollow tube that is vertically and fixedly connected inside the support arm and is configured above the power generation component. Rotate the screw, which is rotatably connected inside the hollow tube; A counterweight, wherein the counterweight is threadedly engaged with the rotating screw; At least two protruding strips are arranged in a circumferential array around the central axis of the rotating screw, and a concave groove is formed on the inner sidewall of the hollow tube to slide and adapt to the protruding strips. The power source is adjusted, and the output power of the power source is transmitted to the rotating screw through a gear pair, so that the counterweight can move up and down along the concave groove inside the hollow tube.

[0014] Optionally, it also includes a limiting component for limiting the maximum plantar flexion, maximum dorsiflexion, maximum internal rotation, maximum external rotation, maximum adduction, or maximum abduction angle of the foot relative to the mounting plate; The limiting component includes a first limiting groove, a second limiting groove, a first limiting block, and a second limiting block; The first limiting block is configured on the output end of the first annular transmission unit, and the first limiting groove is disposed on the mounting bracket on one side of the mounting plate to limit the rotation angle of the first limiting block. The second limiting block is configured on the output end of the second annular transmission unit, and the second limiting groove is provided on the mounting bracket on the other side of the mounting plate to limit the rotation angle of the second limiting block.

[0015] Optionally, it also includes a sensing control component, which is configured to acquire road surface information and road surface smoothness in real time in the path ahead while walking, and plan the position of the next foot step according to the way the user moves their legs.

[0016] As described above, the fully free-degree-of-freedom lower limb bionic prosthesis of the present invention has at least the following beneficial effects: Driven by the power unit, the flipping shaft rotates, and the flexion-extension frame and flipping shaft rotate in tandem. This enables multi-structure linkage control to achieve biomimetic movements in all dimensions, including plantar flexion, dorsiflexion, internal rotation, external rotation, adduction, and abduction. This results in fast response speed and high adjustment precision for various foot postures, dynamically adapting to different road conditions and walking conditions. When walking, turning, climbing, or traversing uneven surfaces, the foot can adjust its posture in real time according to the road surface, ensuring even force distribution and stable center of gravity. This makes it suitable for various scenarios such as daily commuting, outdoor walking, and light exercise. When walking while wearing the prosthesis, the ankle component adaptively adjusts the foot posture using the multi-degree-of-freedom transmission structure of the power unit, ensuring both bionic walking and walking safety. The vibrations generated during walking and the ambient wind force synchronously drive the power generation component on the support arm to generate and store energy, continuously supplying power to the ankle component's power unit. This forms a bionic motion execution, environmental mechanical energy harvesting and storage, and power unit operation, enabling the prosthesis to achieve long-term self-sustaining power supply. This meets the needs of patients for long-distance outdoor travel, thereby solving the shortcomings of limited battery capacity and short battery life, reducing the need for frequent disassembly and charging, and improving the convenience of daily use. Attached Figure Description

[0017] Figure 1 The diagram shown is a three-dimensional structural schematic of the present invention. Figure 2 The diagram shows a three-dimensional structural schematic of the ankle assembly and center of gravity adjustment assembly of the present invention in combination; Figure 3 The diagram shown is an exploded view of the ankle component of the present invention. Figure 4 Shown is an exploded view of the ankle assembly of the present invention from another perspective; Figure 5 The diagram shown is a three-dimensional structural schematic of the power generation component of the present invention. Figure 6 The image shown is a cross-sectional view of the power generation component of the present invention. Figure 7 The diagram shown is a cross-sectional view of the power generation section of the present invention. Figure 8 The diagram shown is a three-dimensional structural schematic of the elastic part of the present invention. Figure 9 The diagram shown is an exploded view of the center-of-gravity adjustment component of this invention.

[0018] Component designation explanation Footplate 1, Support arm 2, Through hole 21, Fixing frame 22, Ankle assembly 3, Mounting plate 31, Flipping shaft 32, First bevel gear 321, Bending and extending frame 33, Rotating sleeve 331, Connecting hole 332, Connecting arm 34, Second bevel gear 341, Power unit 35, First power source 351, Second power source 352, First ring transmission unit 353, First flipping pulley 3531, Second flipping pulley 3532, Flipping belt 3533, Second ring transmission unit 354, First bending and extending pulley 3541, Second bending and extending pulley 3542, Bending and extending belt 3543, Mounting frame 36, Power generation assembly 4 41. Generating cylinder 42. Tube body 43. Generating part 43. Flexible piezoelectric film 431. First electrode 432. Second electrode 433. First outer layer 434. Second outer layer 435. Vibration space 44. Elastic part 45. Avoidance cylinder 451. Avoidance hole 4511. Sliding rod 452. Elastic element 453. Center of gravity adjustment assembly 5. Hollow tube 51. Rotating screw 52. Counterweight block 53. Protruding strip 54. Concave groove 55. Adjustment power source 56. First gear 57. Second gear 58. Limiting assembly 6. First limiting groove 61. Second limiting groove 62. First limiting block 63. Second limiting block 64. Ankle guard 7. Detailed Implementation

[0019] The following specific embodiments illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification.

[0020] Please see Figures 1 to 9 It should be understood that the structures, proportions, sizes, etc., depicted in the accompanying drawings are merely for illustrative purposes to aid those skilled in the art and to facilitate understanding. They are not intended to limit the scope of the invention and therefore have no substantial technical significance. Any modifications to the structure, changes in proportions, or adjustments to size, without affecting the effectiveness and purpose of the invention, should still fall within the scope of the technical content disclosed herein. Furthermore, the terms "upper," "lower," "left," "right," "middle," and "one" used in this specification are merely for clarity and not intended to limit the scope of the invention. Changes or adjustments to their relative relationships, without substantially altering the technical content, should also be considered within the scope of the invention.

[0021] The following embodiments are for illustrative purposes only. These embodiments can be combined and are not limited to the content shown in any single embodiment below.

[0022] In this embodiment, please refer to Figures 1 to 9 This invention provides a fully free-degree-of-freedom lower limb bionic prosthesis, comprising: Foot plate 1, support arm 2, ankle assembly 3, and power generation assembly 4; The foot plate 1 and the support arm 2 are connected by the ankle assembly 3; an ankle cover 7 is provided on the outside of the ankle assembly 3. The ankle cover can be made of silicone. The ankle cover 7 is corrugated, and both ends of the ankle cover 7 are fixedly connected to the support arm 2 and the foot plate 1, respectively. This makes it suitable for movements of internal rotation, external rotation, plantar flexion, dorsiflexion, abduction and adduction gait, and also prevents dust and gravel from entering the ankle assembly 3 and interfering with the normal use of the ankle assembly 3.

[0023] The ankle assembly 3 includes a mounting plate 31, a flipping shaft 32, a flexion and extension frame 33, a connecting arm 34, and a power unit 35 that are vertically and fixedly connected to the support arm 2; The two ends of the flipping shaft 32 are rotatably connected to the mounting plate 31 via the mounting bracket 36, and the flipping shaft 32 is provided with a first bevel gear 321; The bending and stretching frame 33 is U-shaped. The two ends of the U-shaped opening of the bending and stretching frame 33 are rotatably connected to the flipping shaft 32 through bearings. A connecting hole 332 is provided in the middle position of the bending and stretching frame 33 and facing the opening direction. The connecting arm 34 is rotatably connected to the connecting hole 332 through bearings. The upper end of the connecting arm 34 has a second bevel gear 341 that meshes with the first bevel gear 321, and the lower end is fixedly connected to the foot plate 1 near the rear end. The power unit 35 is configured to drive the flipping shaft 32 to rotate, and the flexor frame 33 and the flipping shaft 32 to rotate in coordination, so as to control the foot plate 1 to be in one of plantar flexion, dorsiflexion, internal rotation, external rotation, adduction or abduction. The power generation component 4 is configured on the support arm 2 and is suitable for generating vibration of the power generation component 4 during wind and / or walking, and storing the electrical energy generated by the deformation caused by the vibration in the power source. The power source may be located inside the support arm 2 and may be a battery with a charging interface.

[0024] Driven by the power unit 35, the flipping shaft 32 rotates, and the flexion and extension frame 33 and the flipping shaft 32 rotate in tandem. This enables multi-structure linkage control to achieve full-dimensional bionic movements such as plantar flexion, dorsiflexion, internal rotation, external rotation, adduction, and abduction. As a result, the footplate 1 can switch between various postures quickly and with high adjustment precision, dynamically adapting to different road conditions and walking conditions. When walking, turning, climbing, or traversing uneven surfaces, the footplate 1 can adjust its posture in real time according to the road surface, with uniform force and stable center of gravity, adapting to the needs of daily commuting, outdoor walking, and light exercise. When walking while wearing the prosthesis, the ankle component 3 adaptively adjusts the posture of the foot plate 1 using the multi-degree-of-freedom transmission structure of the power unit 35, ensuring both bionic walking and walking safety. The vibrations generated during walking and the ambient wind force synchronously drive the power generation component 4 on the support arm 2 to generate and store energy, continuously supplying power to the power unit 35 of the ankle component 3. This forms a bionic motion execution, environmental mechanical energy harvesting and storage, and power unit 35, enabling the prosthesis to achieve long-term self-sustaining power supply, matching the needs of patients for long-distance outdoor travel, thereby solving the shortcomings of limited battery capacity and short battery life, reducing the need for patients to frequently disassemble and recharge, and improving the convenience of daily use.

[0025] In this embodiment, please refer to Figures 1 to 4 The power unit 35 includes a first power source 351, a second power source 352, a first ring transmission unit 353, and a second ring transmission unit 354. The first power source 351 and the second power source are electrically connected to the power source. The first power source 351 and the second power source 352 include, but are not limited to, motors. In different gaits of the foot 1, such as plantar flexion, dorsiflexion, pronation, or supination, the output speeds of the first power source 351 and the second power source 352 may be the same or different according to the gait requirements. The first annular transmission unit 353 includes a first tumbling pulley 3531, a second tumbling pulley 3532, and a tumbling belt 3533. The first tumbling pulley 3531 is coaxially fixedly engaged with the output shaft of the first power source 351. The second tumbling pulley 3532 is coaxially fixedly engaged with the tumbling shaft 32. The tumbling belt 3533 drives the first tumbling pulley 3531 and the second tumbling pulley 3532. One end of the bending and stretching frame 33 is fixedly provided with a rotating sleeve 331, which is rotatably connected to the flipping shaft 32. The second annular transmission unit 354 includes a first bending and stretching pulley 3541, a second bending and stretching pulley 3542, and a bending and stretching belt 3543. The first bending and stretching pulley 3541 is coaxially fixedly engaged with the output shaft of the second power source 352, and the second bending and stretching pulley 3542 is coaxially fixedly engaged with the rotating sleeve 331. The bending and stretching belt 3543 drives the first bending and stretching pulley 3541 and the second bending and stretching pulley 3542. The bending and stretching belt 3543 and the flipping belt 3543 can be synchronous belts. The synchronous belt can be made of fiberglass / steel wire / Kevlar to improve its strength. The first annular transmission unit 353 and the second annular transmission unit 354 can be provided with existing belt tensioning structures.

[0026] The ankle component 3 is configured to have a first working state and a second working state; When in the first working state, the output power of the first power source 351 is transmitted to the flipping shaft 32 through the first ring transmission unit, so that the first bevel gear 321, which rotates with the flipping shaft 32, drives the second bevel gear 341 to rotate, thereby driving the connecting arm 34 to move the foot plate 1 to extend or retract; wherein, retraction or extension is respectively the foot plate 1 rotating towards the middle of the body or the foot plate 1 rotating towards the sides of the body on the horizontal plane; The specific working process in the first working state is as follows: the second power source 352 stops and locks, the position of the flexion and extension frame 33 is fixed, the first power source 351 is driven by the first ring transmission unit 353 to rotate the flipping shaft 32, the first bevel gear 321 follows the rotation of the flipping shaft 32, meshing and driving the second bevel gear 341 and the connecting arm 34 to rotate around its own central axis, and the rotation of the connecting arm 34 drives the foot plate 1 to complete the inward adduction towards the midline of the human body and the outward abduction away from the midline of the human body in the horizontal plane.

[0027] In the second working state, the first power source 351 and the second power source 352 work together to transmit output power to the flipping shaft 32 and the flexor frame 33 through the first annular unit and the second annular transmission unit 354, respectively. The synergistic effect allows the foot plate 1 to perform plantar flexion, dorsiflexion, internal rotation, or external rotation. For example, when performing plantar flexion / dorsiflexion, the second power source 352 drives the flexor frame 33 to rotate, and the second bevel gear 341 also rotates, thereby driving the connecting arm 34 to rotate. At this time, the first power source 351 drives the flipping shaft 32 to rotate to dynamically respond to rotational compensation of its own rotation, thus enabling plantar flexion / dorsiflexion.

[0028] The specific working process in the second working state is as follows: The second power source 352 works, and drives the rotating sleeve 331 through the second ring transmission unit 354 to drive the flexion frame 33 to rotate around the flipping shaft 32 as the fulcrum. When the flexion frame 33 rotates, it will drive the connecting arm 34 and the second bevel gear 341 to rotate synchronously. At this time, the second bevel gear 341 will passively generate a self-rotation tendency. The controller collects the rotation angle signal of the flexion frame 33 in real time. The first power source 351 outputs a matching compensation speed according to the rotation amount, and drives the flipping shaft 32 and the first bevel gear 321 to actively rotate synchronously, which cancels the passive self-rotation of the second bevel gear 341 caused by the rotation of the flexion frame 33, so that the foot plate 1 completes the plantar flexion (toe down) and dorsiflexion (toe up) actions. Based on pitch and sway compensation, the output speed difference of the first power source 351 is further altered, causing the first bevel gear 321 to generate additional active driving force, which drives the connecting arm 34 to rotate as a whole. This, combined with the pitch and sway motion, synthesizes a complex internal and external rotation ankle movement of the foot plate 1. The speeds of the first power source 351 and the second power source 352 can be matched in real time with the same speed or with different speeds according to the walking conditions (slopes, uneven ground, steps), adapting to different walking conditions.

[0029] In this embodiment, please refer to Figures 5 to 7 The power generation component 4 includes a generator cylinder 41, a tube body 42, and a power generation section 43; The support arm 2 is provided with a through hole 21 extending from the front end to the rear end of the foot plate 1, and the through hole 21 is located above the mounting plate 31; The generating cylinder 41 is fixedly connected to the through hole 21, and has openings at both ends to form a hollow cavity, with the diameter of the middle section being larger than the diameter of the side sections at both ends; The tube body 42 includes a middle section and an end section, which are fixedly connected. The end section is made of a rigid material, and the middle section is made of a flexible material. The tube body 42 is disposed inside the generating cylinder 41, and the outer wall of the tube body 42 and the inner wall of the hollow cavity of the generating cylinder 41 form a vibration space 44. The power generation unit 43 is configured inside the pipe body 42 and is adapted to cause the pipe body 42 to vibrate inside the generator cylinder 41 when wind enters from one end of the pipe body 42 and flows out from the other end, and / or during travel. The power generation unit 43 performs vibration piezoelectric energy conversion and stores the electrical energy output in the power supply.

[0030] A one-way valve can be installed in the rear end section of the pipe body 42; filter screens can be installed in the openings of the front and rear end sections of the pipe body 42 to prevent stone particles from entering, and the inside of the pipe body 42 can be rinsed with water after a period of use to prevent dust accumulation.

[0031] During prosthetic walking, external airflow enters through one end of the generator cylinder 41 of the support arm 2, flows along the axis of the generator cylinder 41 and exits from the other end, forming a continuous airflow. The airflow washes over the flexible middle section of the tube body 42. When the airflow passes through the variable diameter cavity of the generator cylinder 41, which is narrow at both ends and thick in the middle, the airflow velocity and wind pressure change abruptly, and the airflow generates periodic pulsating force on the flexible tube body 42. The tube body 42 obtains free swaying and micro-deformation mobility inside the generator cylinder 41 by relying on the vibration space 44. The flexible tube body 42 is continuously vibrated by the impact of the airflow pulsation. The power generation part 43 inside the tube body 42 undergoes reciprocating bending deformation synchronously with the tube wall. Relying on the piezoelectric positive effect, the mechanical energy of the airflow is converted into alternating current electrical energy, which is rectified and stabilized and stored in the battery.

[0032] In this embodiment, please refer to Figure 6 The tube 42 is corrugated so that when the wind travels from one end of the tube 42 to the other, vortices are generated at the crests of the corrugations and then detach and enter the troughs. This allows the corrugated structure and the generation and detachment of fluid vortices to increase the power generation of the power generation unit 43.

[0033] When the user moves, the prosthesis and the wind speed generate relative motion speed. The wind flows in through one end of the corrugated tube 42 and out through the other end, which makes the tube 42 vibrate and convert the vibration piezoelectric energy to generate electrical energy output. During the flow, vortices are continuously generated at the crests of the corrugations and then detach and enter the troughs. When the frequency of the vortex shedding is consistent with a certain axial natural frequency of the corrugated tube 42, the corrugated tube structure and the generation and shedding process of the fluid vortex are dynamically coupled, which ultimately causes strong vibration of the corrugated tube 42 and increases the power generation of the generator 43.

[0034] In this embodiment, please refer to Figure 7 The power generation unit 43 includes a flexible piezoelectric film 431, a first electrode 432, a second electrode 433, a first outer layer 434, and a second outer layer 435. The flexible piezoelectric film 431 is disposed in the middle layer of the tube body 42, the first electrode 432 and the second electrode 433 are respectively located above and below the flexible piezoelectric film 431, and the first outer layer 434 and the second outer layer 435 are respectively located outside the first electrode 432 and the second electrode 433. The power source is electrically connected to the first electrode 432 and the second electrode 433.

[0035] During vibration, the flexible piezoelectric film 431 generates significant strain, producing oppositely polarized charges on the surfaces of the first electrode 432 and the second electrode 433 through the positive piezoelectric effect, thus forming an alternating voltage output. This alternating voltage is connected to a rectifier circuit via wires. The rectifier circuit includes at least a full-wave bridge rectifier circuit and a filter capacitor. The full-wave bridge rectifier circuit converts the alternating voltage into a pulsating DC voltage, and the filter capacitor smooths the pulsating DC voltage into a stable DC voltage. Preferably, the filter capacitor is a flexible film capacitor to ensure overall flexibility under bending conditions. The rectifier circuit may also include a DC / DC converter to adjust the voltage to the level required by the battery. The DC power processed by the rectifier circuit is input into the energy storage battery for storage. The energy storage battery is electrically connected to the first power source 351 and the second power source 352, providing power to the first power source 351 and the second power source 352 to drive the first power source 351 and the second power source 352 to work.

[0036] In this embodiment, the flexible piezoelectric film 431 is made of one of the following materials: aluminum nitride, zinc oxide, polyvinylidene fluoride (PVDF), and cadmium oxide (CdO). The first electrode 432 is made of one of aluminum, molybdenum, magnesium and silver, or other metallic conductive materials; The second electrode 433 is made of one of the following materials: Cd, Pb, Ag, Al, Cu, Cr and Au, or other metallic conductive materials. The first outer layer 434 and the second outer layer 435 are made of flexible materials, which are polymeric organic plastics or polymeric organosilicon compounds.

[0037] In this embodiment, please refer to Figure 5 , Figure 6 and Figure 8 The power generation component 4 also includes an elastic part 45. Multiple sets of elastic parts 45 are provided between the outer walls of both ends of the tube body 42 and the inner wall of the generating cylinder 41. The multiple elastic parts 45 are arranged in a circumferential array along the central axis of the tube body 42. The elastic part 45 includes a relief cylinder 451, the central axis of the relief cylinder 451 is perpendicular to the central axis of the generating cylinder 41, the relief cylinder 451 is fixedly connected to the inner wall of the generating cylinder 41, and the relief cylinder 451 is provided with a relief hole 4511 along its own axial direction. A sliding rod 452 is perpendicular to the central axis of the tube body 42 and fixedly connected to the outer wall of the tube body 42. The sliding rod 452 is configured to slide axially along the clearance hole 4511 when an external force is applied. The elastic element 453 is adapted to reset the sliding rod 452 from the inner wall of the generating cylinder 41 toward the central axis of the tube body 42. The elastic element 453 includes a spring, which is sleeved on the sliding rod 452 and its two ends can be fixedly connected to the tube body 42 and the clearance cylinder 451 respectively.

[0038] The specific working process of the above embodiment is as follows: when the airflow acts on the corrugated tube 42 to generate vortex impact, and / or when the walking vibration causes the tube 42 to vibrate, the tube 42 will generate radial displacement. Specifically, the displacement of the tube 42 to one side will push the sliding rod 452 in the corresponding direction to slide into the avoidance cylinder 451, compressing the internal elastic element 453; the elastic element 453 on the opposite side will extend synchronously.

[0039] The sliding rod 452 slides linearly along the clearance cylinder 451. The clearance cylinder 451 restricts the sliding rod 452 to only move radially, limiting the torsion and tilting of the tube body 42. When the external excitation force weakens or changes direction, the compressed elastic element 453 releases its elastic force, pushing the sliding rod 452 to reset, so that the tube body 42 returns to the initial position of the cavity center.

[0040] When under wind-driven excitation: the vortex continuously and alternately impacts the tube body 42, the tube body 42 swings back and forth slightly in the radial range, and the elastic elements 453 are alternately compressed and rebounded, continuously amplifying the vibration amplitude of the tube body 42 and strengthening the deformation of the internal power generation part 43. During walking and / or vibration: the tube body 42 is suspended by the circumferential array elastic part 45, and always maintains a gap with the inner wall of the generating cylinder 41, ensuring that the tube body 42 has sufficient radial movement margin, and the power generation part 43 can continuously generate effective deformation and stabilize power generation output.

[0041] In this embodiment, please refer to Figure 2 and Figure 9 It also includes a center of gravity adjustment component 5, which includes a hollow tube 51, which is vertically and fixedly connected to the support arm 2 and is configured above the power generation component 4. Rotate screw 52, ​​which is rotatably connected inside the hollow tube 51; Counterweight 53, wherein the counterweight 53 is threadedly engaged with the rotating screw 52; At least two protrusions 54 are arranged in a circumferential array around the central axis of the rotating screw 52, ​​and a concave groove 55 is formed on the inner sidewall of the hollow tube 51 in the circumferential direction to slide and adapt to the protrusions 54. The power source 56 is adjusted, including but not limited to a motor. The output power of the power source 56 is transmitted to the rotating screw 52 through a gear pair, so that the counterweight 53 can move up and down along the concave groove 55 in the hollow tube 51. The gear pair includes a first gear 57 and a second gear 58. The second gear 58 is coaxially fixedly engaged with the output shaft of the power source 56. The first gear 57 is rotatably mounted on the fixed frame 22 and meshes with the second gear 58 for transmission. The fixed frame 22 fixes the hollow tube 51 to the support arm 2.

[0042] The center of gravity adjustment component 5 is located inside the support arm 2 and above the power generation component 4. The power source 56 outputs torque through the gear pair consisting of the first gear 57 and the second gear 58, which drives the rotating screw 52 inside the hollow tube 51 to rotate. The outer circumferential protrusion 54 of the counterweight 53 slides with the inner concave groove 55 of the hollow tube 51 to form a circumferential anti-rotation limit, which converts the rotational motion of the screw into the linear motion of the counterweight 53 along the vertical direction of the hollow tube 51, thereby continuously adjusting the height of the counterweight 53 and dynamically changing the overall center of gravity position of the prosthesis.

[0043] The convex strip 54 and concave groove 55 cooperate to prevent the counterweight 53 from spinning freely with the screw. The threaded pair has a self-locking capability. After the counterweight 53 is adjusted to the correct position, it can maintain a stable position and reduce standby power consumption. The fixing frame 22 that carries the second gear 58 also fixes the hollow tube 51, resulting in a high degree of structural integration. The center of gravity height can be adjusted in real time and can cooperate with the multi-degree-of-freedom posture adjustment of the ankle component 3 to adapt to various walking conditions such as flat ground, slopes, and uneven surfaces. It balances the force on the wearer, improves gait, and reduces the risk of falling. The components are arranged vertically in layers along the support arm 2. The center of gravity component, power generation component 4, and ankle transmission mechanism do not occupy each other's assembly space, which facilitates the realization of a compact bionic design for the prosthesis.

[0044] In this embodiment, please refer to Figure 3 and Figure 4 It also includes a limiting component 6, which is used to limit the maximum plantar flexion, maximum dorsiflexion, maximum internal rotation, maximum external rotation, maximum adduction, or maximum abduction angle of the foot plate 1 relative to the mounting plate 31; The limiting component 6 includes a first limiting groove 61, a second limiting groove 62, a first limiting block 63, and a second limiting block 64; wherein the rotatable angle of the first limiting groove 61 is greater than the rotatable angle of the second limiting groove 62. The first limiting block 63 is configured on the output end of the first annular transmission unit 353, and the first limiting groove 61 is disposed on the mounting bracket 36 on one side of the mounting plate 31 to limit the rotation angle of the first limiting block 63. The first limiting block 63 is disposed on the side of the second flipping pulley 3532. The second limiting block 64 is configured on the output end of the second annular transmission unit 354, and the second limiting groove 62 is disposed on the mounting bracket 36 on the other side of the mounting plate 31 to limit the rotation angle of the second limiting block 64. The second limiting block 64 is disposed on the side of the second bending pulley 3542.

[0045] The first power source 351 drives the first ring transmission unit 353 to operate. The second flipping pulley 3532, the flipping shaft 32, and the first bevel gear 321 rotate synchronously. The first limiting block 63 fixed on the side of the second flipping pulley 3532 rotates together. When the first limiting block 63 rotates to the end face of the groove wall of the first limiting groove 61, mechanical abutment occurs, and the second flipping pulley 3532 can no longer rotate in the same direction. This limits the maximum forward and reverse rotation angle of the flipping shaft 32 and constrains the rotation range of the first bevel gear 321. Ultimately, it limits the extreme rotation angles of the foot plate 1 inward rotation, outward rotation, inward retraction, and outward extension, preventing the rotation angle of the foot plate 1 from exceeding the physiological safety range of the human body.

[0046] The second power source 352 drives the second annular transmission unit 354 to operate. The second flexion-extension pulley 3542, the rotating sleeve 331, and the U-shaped flexion-extension frame 33 swing synchronously around the flipping shaft 32. The second limiting block 64 rotates synchronously with the second flexion-extension pulley 3542. When the second limiting block 64 touches the groove walls at both ends of the second limiting groove 62, it is blocked, and the flexion-extension frame 33 cannot continue to swing in the same direction. This limits the maximum rotation angle of the flexion-extension frame 33, thereby limiting the lifting and lowering stroke of the connecting arm 34, and achieving a hard limit on the maximum plantar flexion and maximum dorsiflexion angle of the foot plate 1.

[0047] In this embodiment, a sensing control component is also included. The sensing control component is configured to acquire road surface information and road surface flatness in real time in the path ahead while walking, and plan the position of the next step of the foot 1 according to the way the user moves his legs.

[0048] The sensing and control components include an inertial measurement unit, several pressure sensors, angle sensors, a controller, and an image recognition unit. The inertial measurement unit is mounted on the connecting arm 34 to measure the three-dimensional linear and angular motion of the foot plate 1 and calculate the foot posture. Several pressure sensors are evenly arranged on the footplate 1 to measure the force and pressure distribution in different areas of the sole. Based on capacitive, piezoresistive, or piezoelectric sensing technology, the pressure distribution of the sole is analyzed, gait is recognized, and athletic performance is optimized. An angle sensor is mounted on the connecting arm 34 to measure the angle change of the foot plate 1; The image recognition unit is used to acquire road surface information and road surface smoothness in the path trajectory ahead when walking. The image recognition unit is connected to the front of the connecting arm 34, or the outside of the trouser leg facing forward, with a slightly downward viewing angle and a downward angle of about 10°-20°. At the same time, it captures the outline of the road surface 1-3 meters ahead, keeping it in the same direction as the human line of sight. The image recognition unit includes a depth camera and a lidar. The depth camera acquires the road surface information of the foot 1 in the current direction of travel, and the lidar acquires the road surface smoothness of the foot 1 in real time. After being processed by the controller, the unevenness of the road surface, the position coordinate information of the target object, and the spatial shape data in the path trajectory that the foot 1 will pass through are predicted. The target object refers to the bumps, potholes, and slopes of the road surface. The inertial measurement unit, the pressure sensor, the angle sensor, the image recognition unit, the ankle assembly 3, and the center of gravity adjustment assembly 5 are electrically connected to the controller.

[0049] During the journey, a depth camera captures the outline of the road surface ahead, and a lidar scanner acquires three-dimensional elevation data of the road surface. The controller integrates these two types of data to identify targets such as potholes, bumps, and slopes ahead, calculates the road surface smoothness, obstacle coordinates, and spatial geometry, and predicts the road conditions for the next 1-3 meters of the journey. The inertial measurement unit collects the three-dimensional linear acceleration and angular velocity of the footplate 1, and calculates the real-time spatial attitude and movement speed of the footplate 1. An angle sensor directly measures the real-time angle change of the footplate 1 relative to the mounting plate 31, calibrates the attitude calculation results of the inertial unit, and reduces attitude drift error. The pressure sensor on the sole of the foot collects the pressure distribution of the foot plate in different zones, distinguishes between the support phase and the swing phase, identifies the current gait stage (heel landing, full foot support, toe push-off), and judges the degree of force balance. The controller integrates forward-looking information about the road ahead, real-time movement of foot 1, plantar pressure information, and the way the user moves their legs to predict the road conditions and plan the landing posture of foot 1. The controller works in conjunction with ankle component 3 and center of gravity adjustment component 5 to adjust the angle of foot 1 and the height of the prosthesis's center of gravity before foot 1 lands, thereby achieving active adaptive gait control.

[0050] Working principle: During walking, the depth camera and lidar detect the road surface 1-3 meters ahead at a 10°~20° downward angle, identify potholes, bumps, and slopes, and obtain three-dimensional information on the road surface flatness. The inertial measurement unit and angle sensor are located on the connecting arm 34 to measure the three-dimensional motion and posture angle of the foot plate 1 in real time. Multiple pressure sensors are evenly distributed on the foot plate 1 to collect the pressure distribution of the sole of the foot to identify the gait. The controller integrates the forward-looking information of the road ahead, the real-time motion of the foot plate 1, the sole pressure information, and the way the user moves their legs to predict the road conditions and plan the landing posture of the foot plate 1. The controller coordinates with the ankle component 3 to be in the first or second working state, and works in coordination with the center of gravity adjustment component to pre-adjust the angle of the foot plate 1 and the height of the prosthesis's center of gravity before the foot plate 1 lands, thereby achieving active adaptive gait control.

[0051] In summary, this invention drives the flipping shaft 32 to rotate via the power unit 35, and the flexion-extension frame 33 and the flipping shaft 32 rotate in tandem. This enables multi-structure linkage control to achieve biomimetic movements in all dimensions, including plantar flexion, dorsiflexion, internal rotation, external rotation, adduction, and abduction. As a result, the footplate 1 can switch between various postures quickly and with high adjustment accuracy, dynamically adapting to different road conditions and walking conditions. When walking, turning, climbing, or traversing uneven surfaces, the footplate 1 can adjust its posture in real time according to the road surface, with uniform force and stable center of gravity, adapting to the needs of daily commuting, outdoor walking, and light exercise. When walking while wearing the prosthesis, the ankle component 3 adaptively adjusts the posture of the foot plate 1 using the multi-degree-of-freedom transmission structure of the power unit 35, ensuring both bionic walking and walking safety. Vibrations generated during walking and ambient wind simultaneously drive the power generation component 4 on the support arm 2 to generate and store energy, continuously supplying power to the power unit 35 of the ankle component 3. This process of bionic motion execution, environmental mechanical energy harvesting and storage, and powering the power unit 35 enables long-term self-sustaining power supply for the prosthesis, meeting the needs of patients for long-distance outdoor travel. It also solves the shortcomings of limited battery capacity and short battery life, reduces the need for frequent disassembly and charging, and improves the convenience of daily use. Therefore, this invention effectively overcomes the various shortcomings of existing technologies and has high industrial application value.

[0052] The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit the invention. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in the present invention should still be covered by the claims of the present invention.

Claims

1. A fully free-degree-of-freedom lower limb bionic prosthesis, characterized in that, include: Footboard, support arm, ankle assembly, and power generation assembly; The footplate and the support arm are connected via the ankle assembly; The ankle assembly includes a mounting plate, a flipping shaft, a flexion-extension frame, a connecting arm, and a power unit that are vertically and fixedly connected within the support arm; The two ends of the flipping shaft are rotatably connected to the mounting plate via mounting brackets, and a first bevel gear is provided on the flipping shaft; The extension frame is U-shaped. The two ends of the U-shaped opening of the extension frame are rotatably connected to the flipping shaft through bearings. A connecting hole is provided in the middle of the extension frame and facing the opening direction. The connecting arm is rotatably connected to the connecting hole through bearings. The upper end of the connecting arm has a second bevel gear that meshes with the first bevel gear, and the lower end is fixedly connected to the foot plate near the rear end. The power unit is configured to drive the flipping shaft or the flexor frame and the flipping shaft to rotate together, so as to control the foot state to be one of plantar flexion, dorsiflexion, internal rotation, external rotation, adduction or abduction; The power generation component is configured on the support arm and is adapted to generate vibrations in the presence of wind and / or during movement, and to store the electrical energy generated by the deformation caused by the vibrations in the power source.

2. The fully free-degree-of-freedom lower limb bionic prosthesis according to claim 1, characterized in that: The power unit includes a first power source, a second power source, a first ring transmission unit, and a second ring transmission unit, wherein the first power source and the second power source are electrically connected to the power source. The ankle assembly is configured to have a first working state and a second working state; When in the first working state, the output power of the first power source is transmitted to the flipping shaft through the first ring transmission unit, so that the first bevel gear rotating with the flipping shaft drives the second bevel gear to rotate, thereby driving the connecting arm to move the foot plate to extend outward or retract inward; When in the second working state, the first power source and the second power source work together to transmit the output power to the flipping shaft and the flexion-extension frame through the first ring unit and the second ring transmission unit, respectively. The synergistic effect allows the foot plate to perform plantar flexion, dorsiflexion, internal rotation or external rotation.

3. The fully free-degree-of-freedom lower limb bionic prosthesis according to claim 1, characterized in that: The power generation assembly includes a generator cylinder, a tube body, and a power generation section; The support arm is provided with a through hole extending from the front end to the rear end of the foot plate, and the through hole is located above the mounting plate; The generating cylinder is fixedly connected to the through hole, and has openings at both ends to form a hollow cavity, with the diameter of the middle section being larger than the diameter of the side sections at both ends; The tube is disposed inside the generating cylinder, and the outer wall of the tube and the inner wall of the hollow cavity of the generating cylinder form a vibration space; The power generation unit is configured inside the pipe body and is adapted to cause the pipe body to vibrate inside the generating cylinder when wind enters from one end of the pipe body and flows out from the other end, and / or during travel. The power generation unit performs vibration piezoelectric energy conversion and stores the electrical energy output in the power supply.

4. The fully free-degree-of-freedom lower limb bionic prosthesis according to claim 3, characterized in that: The tube is corrugated so that as the wind travels from one end of the tube to the other, vortices are generated at the crests of the corrugations and then escape into the troughs. This allows the corrugated structure and the generation and detachment of fluid vortices to increase the power generation of the power generation unit.

5. The fully free-degree-of-freedom lower limb bionic prosthesis according to claim 3, characterized in that: The power generation unit includes a flexible piezoelectric thin film, a first electrode, a second electrode, a first outer layer, and a second outer layer; The flexible piezoelectric film is disposed in the middle layer of the tube body, the first electrode and the second electrode are respectively located above and below the flexible piezoelectric film, and the first outer layer and the second outer layer are respectively located outside the first electrode and the second electrode; The power source is electrically connected to the first electrode and the second electrode.

6. The fully free-degree-of-freedom lower limb bionic prosthesis according to claim 5, characterized in that: The flexible piezoelectric film material is made of one of the following: aluminum nitride, zinc oxide, polyvinylidene fluoride (PVDF), and cadmium oxide (CdO). The first electrode is made of one of the following materials: aluminum, molybdenum, magnesium, and silver. The second electrode is made of one of the following materials: Cd, Pb, Ag, Al, Cu, Cr, and Au. The first outer layer and the second outer layer are made of flexible materials, which are polymeric organic plastics or polymeric organosilicon compounds.

7. The fully free-degree-of-freedom lower limb bionic prosthesis according to claim 3, characterized in that: The power generation component also includes elastic parts, and multiple sets of elastic parts are provided between the outer walls of both ends of the tube and the inner wall of the generating cylinder, and the multiple elastic parts are arranged in a circumferential array along the central axis of the tube; The elastic part includes a relief cylinder, the central axis of which is perpendicular to the central axis of the generating cylinder. The relief cylinder is fixedly connected to the inner wall of the generating cylinder, and the relief cylinder is provided with a relief hole along its own axial direction. A sliding rod, which is perpendicular to the central axis of the tube and fixedly connected to the outer wall of the tube, is configured to slide axially along the clearance hole when an external force is applied; An elastic element is provided, which is adapted to reset the sliding rod from the inner wall of the generating cylinder toward the central axis of the tube.

8. The fully free-degree-of-freedom lower limb bionic prosthesis according to claim 1, characterized in that: It also includes a center of gravity adjustment component, which includes a hollow tube that is vertically and fixedly connected inside the support arm and is configured above the power generation component; Rotate the screw, which is rotatably connected inside the hollow tube; A counterweight, wherein the counterweight is threadedly engaged with the rotating screw; At least two protruding strips are arranged in a circumferential array around the central axis of the rotating screw, and a concave groove is formed on the inner sidewall of the hollow tube to slide and adapt to the protruding strips. The power source is adjusted, and the output power of the power source is transmitted to the rotating screw through a gear pair, so that the counterweight can move up and down along the concave groove inside the hollow tube.

9. The fully free-degree-of-freedom lower limb bionic prosthesis according to claim 2, characterized in that: It also includes a limiting component for limiting the maximum plantar flexion, maximum dorsiflexion, maximum internal rotation, maximum external rotation, maximum adduction, or maximum abduction angle of the foot relative to the mounting plate; The limiting component includes a first limiting groove, a second limiting groove, a first limiting block, and a second limiting block; The first limiting block is configured on the output end of the first annular transmission unit, and the first limiting groove is disposed on the mounting bracket on one side of the mounting plate to limit the rotation angle of the first limiting block. The second limiting block is configured on the output end of the second annular transmission unit, and the second limiting groove is provided on the mounting bracket on the other side of the mounting plate to limit the rotation angle of the second limiting block.

10. The fully free-degree-of-freedom lower limb bionic prosthesis according to any one of claims 1-9, characterized in that: It also includes a perception control component, which is configured to acquire road surface information and road surface smoothness in real time in the path ahead while walking, and plan the position of the next foot step according to the way the user moves his legs.

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