Ankle joint assistance for a lower leg exoskeleton

Abstract

The present application relates to the technical fields of bionic ankle joint driving mechanism, and specifically provides a lower leg exoskeleton with ankle joint assistance, which comprises a lower leg supporting assembly, a lower leg support connected with a foot supporting assembly through a universal ball shaft, the universal ball shaft comprising a ball socket support and a ball head rotating shaft, the ball socket support being fixedly installed at the lower end of the lower leg support, the spherical head of the ball head rotating shaft being embedded in the spherical groove of the ball socket support, and the protruding part of the ball head rotating shaft being fixedly installed on the foot supporting assembly; and a driving assembly comprising an electric cylinder, an electric cylinder support and a fisheye bearing, the fixed end of the electric cylinder being hinged to the lower leg support through the electric cylinder support, and the output end of the electric cylinder being hinged to the foot supporting assembly near the rear part of the foot through the fisheye bearing, so as to solve the problem that the ankle joint exoskeleton in the related art adopts the transmission mode of motor driving rope, resulting in poor transmission efficiency and being unable to simulate the natural movement of the ankle joint.

Description

Technical Field

[0001] This invention relates to the field of bionic ankle joint drive mechanism technology, and in particular to a lower leg exoskeleton with ankle joint assistance. Background Technology

[0002] With the increasing demand for enhanced human mobility in high-intensity work fields such as industrial handling, military load-bearing, and fire rescue, ankle-assisted exoskeleton technology, as a technology that can effectively restore motor function, reduce human energy consumption, and improve work efficiency, has shown great application value and development potential in fields such as medical rehabilitation, industrial production, and national defense security.

[0003] The ankle-assistive exoskeleton technology in related fields uses an indirect transmission structure with a motor driving a rope, which suffers from problems such as high transmission loss, slow response speed, and low control precision. Furthermore, most products can only provide active assistance in a single plane of dorsiflexion or plantarflexion, lacking the passive adaptation degrees of freedom necessary for the natural movement of the ankle joint, such as inversion or eversion, internal rotation or external rotation. This results in stiff gait and limited movement for the wearer, making them highly susceptible to ankle sprains when walking on uneven surfaces. To compensate for the deficiencies in transmission and degrees of freedom, numerous auxiliary mechanisms are often added, leading to an excessively heavy exoskeleton that further burdens the wearer.

[0004] There is currently no effective solution to the problem that the ankle exoskeleton in related technologies uses a motor-driven rope transmission method, which results in poor transmission efficiency and an inability to simulate the natural movement of the ankle joint. Summary of the Invention

[0005] The present invention provides a lower leg exoskeleton with ankle joint assistance, which at least solves the problem in related technologies where ankle exoskeletons use a motor-driven rope transmission method, resulting in poor transmission efficiency and an inability to simulate natural ankle joint movement.

[0006] According to one aspect of the present invention, a lower leg exoskeleton with ankle joint assistance is provided, comprising: a lower leg support assembly, a foot support assembly, and a drive assembly; the lower leg support assembly includes a lower leg bracket and a universal ball joint; the lower leg bracket is connected to the foot support assembly via the universal ball joint; the universal ball joint includes a ball socket bracket and a ball head pivot; the ball socket bracket is fixedly installed at the lower end of the lower leg bracket, the spherical head of the ball head pivot is embedded in the spherical groove of the ball socket bracket, and the protrusion of the ball head pivot is fixedly installed on the foot support assembly; the drive assembly includes an electric cylinder, an electric cylinder bracket, and a fisheye bearing; the fixed end of the electric cylinder is hinged to the lower leg bracket via the electric cylinder bracket; the output end of the electric cylinder is hinged to the foot support assembly near the posterior part of the foot via the fisheye bearing; the fisheye bearing can keep the output axis of the electric cylinder coaxial with the connecting axis of the fisheye bearing, so that the electric cylinder extends and retracts to drive the foot support assembly to rotate around the ball head pivot, thereby realizing dorsiflexion and plantarflexion movements of the ankle joint.

[0007] As an optional solution, the electric cylinder drives the foot support assembly to rotate around the ball joint axis via the electric cylinder bracket, achieving a range of motion where the maximum dorsiflexion angle is 35° relative to the neutral position of the ankle joint and the maximum plantarflexion angle is 45° relative to the neutral position of the ankle joint; wherein, the neutral position of the ankle joint refers to the position where the lower leg and the sole of the foot form a 90° angle; the electric cylinder bracket includes a first rotating shaft and a U-shaped frame; the first rotating shaft is fixedly installed on the lower leg support, and the bottom center of the U-shaped frame is fixedly connected to the first rotating shaft, so that the U-shaped frame can rotate around the axis of the first rotating shaft; the two free ends of the U-shaped frame are respectively provided with rotating bearings, and the fixed ends of the electric cylinder are respectively connected to the two rotating bearings, so that the electric cylinder can rotate around the axis of the rotating bearings; the axis of the first rotating shaft is perpendicular to the axis of the rotating bearings to ensure that the electric cylinder has no motion interference and no loss of output torque throughout the entire range of motion.

[0008] As an optional solution, the ball joint support has an annular damping ring on its inner wall; the ball joint support is equipped with a damping adjustment mechanism to adjust the clamping force between the annular damping ring and the ball joint shaft, thereby forming an adjustable damping structure; the ball joint allows the foot support component to passively achieve inversion, eversion and rotation around the lower leg axis with the movement of the human ankle, and to remain stable in any rotation position.

[0009] As an optional solution, the calf support includes a posterior calf support, a front calf support, and a side calf support, all of which are connected to a lower calf groove. The lower calf groove matches the shape of the lower calf near the ankle joint. The posterior calf support is fixedly installed on the rear side of the lower calf groove. The front calf support is hinged to the front side of the lower calf groove and can rotate relative to the posterior calf support to adjust its position to fit the shape of the front side of the lower calf. The side calf support is installed on the side of the lower calf groove and has an adjustable mechanism. The adjustable mechanism is used to adjust the overall length of the corresponding side calf support so that the corresponding universal joint is aligned with the rotation center of the ankle joint. The universal joint is fixedly installed at the lower end of the side calf support.

[0010] As an optional solution, the adjustable mechanism is located at the end of the lower leg side support away from the ankle joint, forming a sliding groove structure with the lower leg side support; the adjustable mechanism includes an adjustable slider and a locking handle, the adjustable slider slides in cooperation with the sliding groove structure, and the length adjustment range is 0~75mm; the adjustable slider is pressed and fixed to the lower leg side support by the locking handle; the upper end of the adjustable slider is provided with an external thread for fixed connection with the lower end of the thigh exoskeleton, so as to realize the synchronous movement of the lower leg exoskeleton and the thigh exoskeleton.

[0011] As an optional solution, the front calf support includes a front support and an upper slot; the lower end of the front support is hinged to the lower calf slot, and the upper slot is fixedly installed on the upper end of the front support, matching the shape of the upper front side of the human calf; the rear calf support includes a rear support and an upper support plate; the lower end of the rear support is fixed to the lower calf slot, and the upper support plate is fixedly installed on the upper end of the rear support, matching the shape of the upper rear side of the human calf.

[0012] As an optional solution, the foot support assembly includes a front foot support, a rear foot support, and an adjustable locking buckle; the front foot support is connected to the rear foot support via the adjustable locking buckle; the adjustable locking buckle is used to adjust the distance between the front foot support and the rear foot support, and the extension and retraction adjustment range of the adjustable locking buckle is 5~45mm; the foot support assembly also includes an adjustable strap, which is disposed on the front foot support for fitting and fixing the human foot.

[0013] As an optional solution, the forefoot support includes a foot support plate, two side plates, and an upper plate; the two side plates are respectively fixedly installed on both sides of the foot support plate, forming a U-shaped structure that conforms to the shape of the foot and surrounds both sides of the foot; the upper plate is fixedly installed on the upper end of the two side plates, at a preset angle to the foot support plate to adapt to the height of the human foot; the rearfoot support includes a main board, a first connector, a second connector, and a heel guard; one end of the first connector is fixedly connected to the upper end of the main board, and the other end is fixedly connected to the protrusion of the ball joint shaft; the heel guard is fixedly installed on the side of the main board away from the forefoot support, for conforming to the human heel; the fixed end of the adjustable locking buckle is fixedly connected to the rear end of the two side plates, the movable end of the adjustable locking buckle is fixedly connected to both ends of the second connector, and the second connector is fixedly installed on the front end of the main board.

[0014] As an optional solution, the lower leg slot is a circular slot structure with a front opening, and the lower leg side brackets are two symmetrically arranged structures; the lower ends of the two lower leg side brackets are respectively fixedly installed on the inner walls of the left and right sides of the circular slot structure, surrounding the human lower leg from both sides; a universal ball joint is fixedly installed on the lower ends of the two lower leg side brackets, and the ball joint head protrusions of the two universal ball joints are respectively fixedly connected to the left and right sides of the foot support assembly; a closing plate is rotatably installed at the front opening of the circular slot structure, and the lower leg front bracket is fixedly installed on the closing plate.

[0015] According to another aspect of the invention, a human exoskeleton is also provided, comprising a trunk exoskeleton and at least one lower leg exoskeleton with ankle joint assistance as described in any of the preceding claims, the lower leg exoskeleton being connected to the trunk exoskeleton.

[0016] This invention provides a calf exoskeleton with ankle joint assistance. It uses an electric cylinder as a power source, directly hinged to the foot support component via a fisheye bearing. This eliminates energy loss caused by rope stretching and deformation, pulley friction, etc., while achieving bidirectional and precise torque transmission, resulting in faster response and higher control accuracy. Furthermore, the universal ball joint hinge structure between the calf support and the foot support component provides passive adaptation degrees of freedom for inversion, eversion, and rotation around the calf axis. This allows for complete replication of the three-dimensional natural movement trajectory of the human ankle joint. Combined with the dual-degree-of-freedom hinged bracket at the fixed end of the electric cylinder and the fisheye bearing at the output end, the electric cylinder can automatically deflect during any spatial movement of the foot, always maintaining coaxiality between the output axis and the connecting axis. This avoids torque dispersion and motion interference, ensuring the assistance process perfectly matches the natural gait of the human body. This solves the problem in related technologies where ankle exoskeletons use a motor-driven rope transmission method, resulting in poor transmission efficiency and an inability to simulate natural ankle joint movement. Attached Figure Description

[0017] The accompanying drawings, which are included to provide a further understanding of this application and form part of this application, illustrate exemplary embodiments and are used to explain this application, but do not constitute an undue limitation of this application. In the drawings:

[0018] Figure 1 This is a schematic diagram of the overall structure of a lower leg exoskeleton with ankle joint assistance, according to an embodiment of the present invention.

[0019] Figure 2 yes Figure 1 A schematic diagram of the rear view structure.

[0020] Figure 3 yes Figure 1 A side view structural diagram.

[0021] Figure 4 yes Figure 1 Another side view of the structure.

[0022] Figure 5 This is a side view of the motion state of the exoskeleton without the forefoot support in an embodiment of this application.

[0023] Figure 6 yes Figure 1 A top-view structural diagram.

[0024] Figure 7 This is a schematic diagram of a universal ball joint according to an embodiment of this application.

[0025] The above figures include the following reference numerals:

[0026] 1. Lower leg support assembly; 11. Lower leg bracket; 12. Universal ball joint; 121. Ball socket bracket; 122. Ball head pivot; 111. Lower leg rear bracket; 1111. Rear side bracket; 1112. Upper support plate; 112. Lower leg front bracket; 1121. Front side bracket; 1122. Upper slot; 113. Lower leg side bracket; 114. Lower leg lower end slot; 115. Adjustable mechanism; 1151. Adjustable slider; 1152. Locking handle;

[0027] 2. Foot support assembly; 21. Forefoot support; 22. Rearfoot support; 23. Adjustable locking buckle; 24. Adjustable strap; 211. Foot support plate; 212. Side panels; 213. Upper panel; 221. Main board; 222. First connector; 223. Second connector; 224. Heel guard.

[0028] 3. Drive assembly; 31. Electric cylinder; 32. Electric cylinder bracket; 33. Fisheye bearing; 321. First rotating shaft; 322. U-shaped frame. Detailed Implementation

[0029] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. This application will now be described in detail with reference to the accompanying drawings and embodiments.

[0030] 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 exemplary embodiments according to this application. 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.

[0031] Unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps described in these embodiments do not limit the scope of this application. 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 drawings denote similar items; therefore, once an item is defined in one drawing, it need not be further discussed in subsequent drawings.

[0032] The ankle-assisted exoskeleton technology in related technologies employs an indirect transmission structure where a motor drives a rope. As a flexible transmission element, the rope can only withstand axial tension and is completely incapable of withstanding pressure, bending moment, and torque. When the motor pulls the foot through the rope to achieve plantar flexion, the rope is taut and can effectively transmit torque. However, when dorsiflexion is required, a single rope will slack and lose its force-transmitting capacity, necessitating the addition of a reverse rope or a spring-reset mechanism. This not only doubles the complexity of the transmission system but also causes transmission gaps and response lag due to difficulties in adjusting the rope preload.

[0033] Meanwhile, the human ankle joint is a typical three-degree-of-freedom ball-and-hinge joint. In addition to planar dorsiflexion and plantarflexion, it also exhibits lateral tilting movements such as inversion and eversion, as well as torsional movements around the lower leg axis. However, cable transmission relies on a planar guiding mechanism composed of fixed or movable pulleys, which strictly restricts the direction of force transmission to a single plane. When the foot undergoes three-dimensional spatial movement, the cable will deviate from the design plane of the pulley groove, resulting in severe lateral friction and the risk of cable derailment. At the same time, the cable length will change unexpectedly due to spatial deflection, leading to a loss of control precision and an inability to accurately follow the natural movement trajectory of the ankle joint.

[0034] See Figures 1 to 7 As shown, to address the problem in related technologies where ankle exoskeletons use a motor-driven rope transmission method, resulting in poor transmission efficiency and an inability to simulate natural ankle joint movement, this application provides a lower leg exoskeleton with ankle joint assistance, comprising: a lower leg support component 1, a foot support component 2, and a drive component 3; the lower leg support component 1 includes a lower leg bracket 11 and a universal ball joint 12; the lower leg bracket 11 is connected to the foot support component 2 via the universal ball joint 12; the universal ball joint 12 includes a ball socket bracket 121 and a ball head pivot 122; the ball socket bracket 121 is fixedly installed at the lower end of the lower leg bracket 11, and the ball head pivot 122... The spherical head of the ball joint 22 is embedded in the spherical groove of the ball joint bracket 121, and the protrusion of the ball joint shaft 122 is fixedly installed on the foot support assembly 2; the drive assembly 3 includes an electric cylinder 31, an electric cylinder bracket 32, and a fisheye bearing 33; the fixed end of the electric cylinder 31 is hinged to the lower leg bracket 11 through the electric cylinder bracket 32; the output end of the electric cylinder 31 is hinged to the foot support assembly 2 near the back of the foot through the fisheye bearing 33; the fisheye bearing 33 can keep the output axis of the electric cylinder coaxial with the connecting axis of the fisheye bearing, so that the electric cylinder 31 can extend and retract to drive the foot support assembly 2 to rotate around the ball joint shaft 122, thereby realizing the dorsiflexion and plantarflexion movements of the ankle joint.

[0035] Based on the natural standing posture of the human body with feet shoulder-width apart and toes pointing forward, the directional references of this scheme are defined as follows: front-back direction is the front of the human body facing forward and back-back direction is the back; left-right direction is the left side of the human body and right side is the right; up-down direction is the direction of the human body head facing up and feet facing down.

[0036] This invention relates to a lower leg exoskeleton with ankle joint assistance, which is assembled on the lower leg and foot of one side of the human body. It can be used alone to realize the ankle joint assistance function, or it can be connected with the thigh exoskeleton and the trunk exoskeleton to form a complete lower limb assistance exoskeleton system.

[0037] The ankle-assisted lower leg exoskeleton of this invention consists of three core components: a lower leg support component 1, which is fitted to the lower leg and provides basic support and mounting reference for the entire exoskeleton system; a foot support component 2, which is fitted to the foot and directly follows foot movement, transmitting assist torque; and a drive component 3, which connects the lower leg support component 1 and the foot support component 2, providing power for active ankle joint movement. These three components form an organic whole through specific connections, jointly achieving active assistance in ankle dorsiflexion and plantarflexion, as well as passive adaptation functions for inversion, eversion, and rotation around the lower leg axis.

[0038] The calf support component 1 includes a calf bracket 11 and a universal ball joint 12. The calf bracket 11 adopts an ergonomic arc design and can be tightly fixed to the back of the calf using straps. The universal ball joint 12 is located between the lower end of the calf bracket 11 and the upper end of the foot support component 2, forming a hinged connection between the calf bracket 11 and the foot support component 2. This design, by using the universal ball joint 12 as a connecting component between the calf and the foot, aims to provide multi-degree-of-freedom rotation capabilities, enabling the foot support component 2 to rotate freely in three-dimensional space relative to the calf bracket 11. This improves the wearing comfort and motion adaptability of the exoskeleton, while also providing a stable foundation for the efficient transmission of the drive component 3.

[0039] The universal ball joint 12 includes a ball joint bracket 121 and a ball joint shaft 122. The ball joint bracket 121 is a cylindrical structure with one open end, and has a spherical groove inside that matches the spherical head of the ball joint shaft 122. The closed end of the ball joint bracket 121 is fixedly installed to the lower end face of the lower leg support 11 by screws. One end of the ball joint shaft 122 is a spherical head, and the other end is a cylindrical non-spherical protrusion. The spherical head is embedded in the spherical groove of the ball joint bracket 121, and the two are precisely clearance-fitted. The non-spherical protrusion is fixedly installed to the upper end face of the foot support assembly 2 by interference fit and locking nut.

[0040] The human ankle joint is a three-degree-of-freedom ball-and-hinge joint. In addition to active dorsiflexion and plantarflexion, it also requires passive inversion, eversion, and rotation around the lower leg axis to adapt to different road conditions and movement postures. The ball joint support 121 and ball joint 122 of the universal ball joint 12 form a simple and reliable ball joint, enabling the foot support component 2 to passively achieve inversion, eversion, and rotation around the lower leg axis with the movement of the human ankle. This effectively solves the problem of insufficient freedom of movement in traditional exoskeletons, prevents ankle sprains when walking on uneven surfaces, and also makes the assist process more in line with the natural gait of the human body.

[0041] The drive assembly 3 includes an electric cylinder 31, an electric cylinder bracket 32, and a fisheye bearing 33. The electric cylinder bracket 32 ​​is fixedly installed at a position slightly above the middle of the lower leg support 11. The fixed end of the electric cylinder 31 is hinged to the lower leg support 11 through the electric cylinder bracket 32. The output end of the electric cylinder 31 has an external thread structure. The inner ring of the fisheye bearing 33 is threaded to the output end of the electric cylinder 31 and is locked by a lock nut after tightening. The outer ring of the fisheye bearing 33 is hinged to the foot support assembly 2 near the heel through a pin. The pin and the outer ring of the fisheye bearing 33 are in transition fit.

[0042] This solution adopts a direct-drive structure of electric cylinder 31, which can eliminate energy loss caused by rope transmission and improve transmission efficiency and control accuracy. At the same time, by setting electric cylinder bracket 32 ​​and fisheye bearing 33, the posture change of electric cylinder 31 during movement can be compensated to ensure that the output axis is always coaxial and avoid torque dispersion.

[0043] The upper end of the foot support component 2 is fixedly connected to the non-spherical protrusion of the ball joint shaft 122, and the position near the heel is hinged to the outer ring of the fisheye bearing 33. The foot support component 2 is tightly fixed to the human foot by a strap, and can move synchronously with the human foot. As the actuator of the assist torque, the foot support component 2 can stably transmit the assist torque generated by the drive component 3, and at the same time follow the human foot to achieve free movement in three-dimensional space, so that the assist torque is precisely matched with the human movement needs to achieve the best assist effect.

[0044] The ankle-assisted lower leg exoskeleton of the present invention, when the human body needs to perform plantar flexion movement, that is, when the toes press down, the output end of the electric cylinder 31 extends and pushes the foot support component 2 to rotate downward around the center of the universal ball shaft 12 through the fisheye bearing 33, thereby driving the human ankle joint to complete the plantar flexion movement, providing assistance for the push-off force stage when walking.

[0045] When the human body needs to perform dorsiflexion, that is, when the toes are pointed upward, the output end of the electric cylinder 31 retracts, and pulls the foot support component 2 to rotate upward around the center of the universal ball shaft 12 through the fisheye bearing 33, thereby driving the human ankle joint to complete the dorsiflexion movement, providing assistance for lifting the leg to pass over obstacles when walking.

[0046] During the aforementioned active assistance process, when the human foot undergoes inversion, eversion, or rotation around the lower leg axis, the foot support component 2 will rotate synchronously relative to the lower leg bracket 11 via the universal ball joint 12. The electric cylinder 31 will automatically adjust its own posture through the dual-degree-of-freedom hinge of the electric cylinder bracket 32 ​​and the automatic self-aligning function of the fisheye bearing 33, so that the output axis of the electric cylinder 31 always remains coaxial with the connecting shaft, avoiding torque dispersion and motion interference, and ensuring efficient transmission of assist torque.

[0047] This invention provides a calf exoskeleton with ankle joint assistance, using an electric cylinder 31 as a power source. The cylinder is directly hinged to the foot support component 2 via a fisheye bearing 33, eliminating energy loss caused by rope stretching and deformation, pulley friction, etc., while achieving bidirectional and precise torque transmission, resulting in faster response and higher control accuracy. Furthermore, the universal ball joint 12 hinge structure between the calf support 11 and the foot support component 2 provides passive adaptation degrees of freedom for inversion, eversion, and rotation around the calf axis, completely replicating the three-dimensional natural movement trajectory of the human ankle joint. Combined with the dual-degree-of-freedom hinged bracket at the fixed end of the electric cylinder 31 and the fisheye bearing 33 at the output end, the electric cylinder 31 can automatically deflect during any spatial movement of the foot, always maintaining the output axis coaxial with the connecting axis, avoiding torque dispersion and motion interference. This ensures the assistance process perfectly matches the natural gait of the human body, thus solving the problem in related technologies where ankle exoskeletons use a motor-driven rope transmission method, resulting in poor transmission efficiency and an inability to simulate natural ankle joint movement.

[0048] As an optional solution, the electric cylinder 31 drives the foot support assembly 2 to rotate around the ball joint shaft 122 via the electric cylinder bracket 32, achieving a range of motion where the maximum dorsiflexion angle is 35° relative to the neutral position of the ankle joint and the maximum plantarflexion angle is 45° relative to the neutral position of the ankle joint; where the neutral position of the ankle joint refers to the position where the lower leg and the sole of the foot are at 90°; the electric cylinder bracket 32 ​​includes a first rotating shaft 321 and a U-shaped frame 322; the first rotating shaft 321 is fixedly installed on the lower leg support 11, and the bottom center of the U-shaped frame 322 is fixedly connected to the first rotating shaft 321, so that the U-shaped frame 322 can rotate around the axis of the first rotating shaft 321; the two free ends of the U-shaped frame 322 are respectively provided with rotating bearings, and the fixed ends of the electric cylinder 31 are respectively connected to the two rotating bearings, so that the electric cylinder 31 can rotate around the axis of the rotating bearings; the axis of the first rotating shaft 321 is perpendicular to the axis of the rotating bearings to ensure that the electric cylinder 31 has no motion interference and no loss of output torque throughout the entire range of motion.

[0049] The fixed end of the electric cylinder 31 achieves two degrees of freedom orthogonal rotation through the first rotating shaft 321 and rotating bearing of the electric cylinder bracket 32, and the output end is hinged to the rear foot bracket 22 through the fisheye bearing 33. When the drive component 3 outputs power, it can drive the rear foot bracket 22 to rotate around the center of the ball head rotating shaft 122, accurately assisting the human foot to complete active dorsiflexion and plantarflexion movements in the sagittal plane.

[0050] This embodiment achieves active degrees of freedom for sagittal dorsiflexion / plantar flexion via electric cylinder 31, and simultaneously achieves two passive degrees of freedom for inversion / eversion in the frontal plane and rotation around the lower leg axis in the horizontal plane via universal ball joint 12, thus fully covering the three-dimensional natural movement trajectory of the human ankle joint. When this lower leg exoskeleton is fixedly connected to the lower end of the thigh exoskeleton via the external thread at the upper end of the adjustable slider 1151, the movement of the lower leg and thigh can be synchronized, enabling the three degrees of freedom of the ankle joint to work in coordination with the hip and knee joints, further improving the movement coordination and assist efficiency of the exoskeleton system.

[0051] Using the neutral position of the ankle joint as the benchmark for angle determination, corresponding to the natural standing posture of the human body, the longitudinal axis of the lower leg is perpendicular to the plane of the foot, and there is no dorsiflexion or plantarflexion of the ankle joint. With this as a reference, the movement of lifting the toes is judged as dorsiflexion, and the movement of pressing the toes down is judged as plantarflexion. By standardizing the angle measurement, the system can accurately identify the real-time posture of the ankle joint and control the timing and force of the assist output.

[0052] When the electric cylinder 31 outputs torque, the rear foot support 22 is driven to rotate, and the electric cylinder 31 generates a variable torque of approximately 40 N·m. The angles are calculated through the linkage mechanism, with a maximum angle of 44.63° during dorsiflexion and 51.56° during plantarflexion. Based on human gait analysis, a maximum dorsiflexion angle of 35° and a maximum plantarflexion angle of 45° are set, which can cover the entire gait cycle movement angles.

[0053] The dorsiflexion limit angle is set at 35°, which can meet the needs of regular activities such as walking, going up and down stairs, and crossing obstacles. At the same time, a safety margin is reserved to avoid the problem of redundant stroke of the electric cylinder 31 and structural collision caused by excessive angle. It is fully adapted to the toe lifting movement in daily scenarios.

[0054] The plantar flexion limit angle is set at 45°, which is suitable for force exertion movements such as walking, running, and going downstairs. The ample range of motion ensures the power assist effect, while limiting the maximum deflection range to avoid excessive pressure on the foot and effectively protect the ankle joint from injury.

[0055] The extension and retraction stroke of the electric cylinder 31 is linearly matched with the ankle joint rotation angle. Relying on the dual protection structure of mechanical limit and program limit, it can avoid damage to parts caused by excessive movement when the movement reaches the limit angle.

[0056] In this embodiment, during operation, after the system recognizes the human's movement intention, the retraction of the electric cylinder 31 causes the rear foot support 22 to deflect upward, completing the ankle dorsiflexion movement; the extension of the electric cylinder 31 causes the rear foot support 22 to deflect downward, completing the ankle plantarflexion movement. The angle and component position are monitored in real time throughout the entire operation, always keeping the range of motion within a safe range.

[0057] This embodiment sets the rotation angle according to the physiological movement laws of the human body, comprehensively covering various daily activity conditions. It ensures freedom of movement of limbs while eliminating the risk of structural interference and sports injuries. The angle and stroke are precisely matched, and the protection mechanism is complete, effectively improving the stability of the exoskeleton and its actual use effect.

[0058] The electric cylinder bracket 32 ​​is a two-degree-of-freedom orthogonal hinge structure. Through two mutually perpendicular rotation axes, the electric cylinder 31 can rotate freely in two orthogonal directions in space, which can completely compensate for the changes in the posture of the electric cylinder 31 caused by the three-dimensional movement of the foot.

[0059] The first rotating shaft 321 is a cylindrical stepped shaft structure. One end of the first rotating shaft 321 is provided with a mounting hole and is fixedly installed on the right side mounting surface of the lower leg bracket 11 by screws. The axis extends along the left and right direction of the human body. The other end of the first rotating shaft 321 is a smooth shaft section that passes through the bottom center hole of the U-shaped frame 322 from left to right and cooperates with it. The first rotating shaft 321 provides the electric cylinder 31 with rotational freedom around the left and right axis, compensating for the front and back posture deviation of the electric cylinder 31 caused by the dorsiflexion and plantarflexion movements of the foot.

[0060] The U-shaped frame 322 has a U-shaped structure with its opening facing forward. A mounting hole matching the optical axis section of the first rotating shaft 321 is located at the center of its bottom. The center hole at the bottom of the U-shaped frame 322 and the optical axis section of the first rotating shaft 321 are interference-fitted, allowing the U-shaped frame 322 to rotate freely around the axis of the first rotating shaft 321. The two free ends of the U-shaped frame 322 are located on the front and rear sides, respectively, and symmetrically have bearing mounting holes. Two rotating bearings are interference-fitted into the two bearing mounting holes, with their axes extending along the front-back direction of the human body and coinciding with each other. The U-shaped frame 322 provides the electric cylinder 31 with rotational freedom around its front-back axis, compensating for lateral posture deviations of the electric cylinder 31 caused by inward and outward movements of the foot.

[0061] During operation in this embodiment, when the foot support component 2 moves in three-dimensional space with the ankle, if the foot undergoes inversion or eversion, the U-shaped frame 322 will drive the electric cylinder 31 to rotate around the axis of the first rotating shaft 321, automatically compensating for changes in the foot's posture in the left-right direction; if the foot undergoes dorsiflexion or plantarflexion, the electric cylinder 31 will rotate around the axis of the rotating bearing, automatically compensating for changes in the foot's posture in the front-back direction. Through the combined motion of two mutually perpendicular rotational degrees of freedom, the electric cylinder 31 can arbitrarily adjust its posture in space, always maintaining the output axis coaxial with the connecting shaft of the fisheye bearing 33.

[0062] This embodiment further improves the system's transmission efficiency by adopting a two-degree-of-freedom orthogonally hinged electric cylinder bracket 32 ​​structure, while extending the service life of the electric cylinder 31, avoiding motion interference and jamming, making the assistance process smoother and more natural, and significantly improving the reliability and durability of the exoskeleton.

[0063] As an optional solution, the ball joint bracket 121 of the universal ball joint 12 has an annular damping ring on its inner wall; the ball joint bracket 121 is provided with a damping adjustment mechanism to adjust the clamping force between the annular damping ring and the ball joint shaft 122, thereby forming an adjustable damping structure; the universal ball joint 12 can make the foot support component 2 passively realize inversion, eversion and rotation around the lower leg axis with the movement of the human ankle, and remain stable in any rotation position.

[0064] The universal ball joint 12 is a ball joint structure with adjustable damping. Through the cooperation of the annular damping ring and the damping adjustment mechanism, the damping magnitude can be continuously adjusted, which enables the foot support component 2 to move flexibly with the human ankle while maintaining stability in any rotation position, providing reliable support and protection for the ankle joint.

[0065] The annular damping ring is made of wear-resistant, self-lubricating polytetrafluoroethylene (PTFE) material. It has an open, circular annular structure and is embedded in the annular mounting groove on the inner wall of the ball joint bracket 121. The inner spherical surface of the annular damping ring is fully fitted to the outer surface of the spherical head of the ball joint shaft 122, with an interference fit between them. The frictional resistance between the damping ring and the ball joint shaft 122 provides appropriate damping for the rotation of the universal ball joint 12, preventing excessive swaying and free movement of the foot support component 2 during exercise. This effectively absorbs impact and vibration during exercise, preventing ankle sprains caused by sudden foot movement, and making the exercise process smoother and more natural.

[0066] The damping adjustment mechanism may include three adjusting screws evenly distributed circumferentially along the ball joint bracket 121. Three threaded holes communicating with the annular mounting groove are correspondingly provided on the side wall of the ball joint bracket 121. The three adjusting screws are threaded into the three threaded holes, and the ends of the adjusting screws abut against the outer surface of the annular damping ring. By synchronously rotating the three adjusting screws, the radial clamping force of the adjusting screws on the annular damping ring can be uniformly changed, thereby changing the contact pressure between the annular damping ring and the ball joint shaft 122, achieving continuous adjustment of the damping magnitude. The damping adjustment mechanism allows the damping of the universal ball joint 12 to be personalized according to the user's weight, exercise intensity, and usage scenario.

[0067] During the operation of this embodiment, when the human foot performs inversion, eversion, or rotation around the lower leg axis, the ball head shaft 122 will rotate synchronously in the spherical groove of the ball socket support 121. The frictional resistance between the annular damping ring and the ball head shaft 122 will provide appropriate damping for the rotation, making the movement process more stable and controllable.

[0068] When the damping needs to be adjusted, simply use an Allen wrench to rotate the three adjusting screws simultaneously to increase or decrease the clamping force on the annular damping ring. When the damping is adjusted to the appropriate value, the foot support component 2 can move flexibly with the ankle and remain stable in any rotational position without rotating or wobbling on its own.

[0069] This embodiment forms a continuously adjustable damping structure by setting an annular damping ring and a circumferentially evenly distributed damping adjustment mechanism inside the universal ball shaft 12. This structure can effectively absorb the impact and vibration during movement, improve the wearing comfort and sports safety of the exoskeleton, meet the personalized needs of different users, and make the exoskeleton more widely applicable.

[0070] As an optional solution, the calf support 11 includes a posterior calf support 111, a front calf support 112, and a side calf support 113. The posterior calf support 111, the front calf support 112, and the side calf support 113 are all connected to a lower calf end slot 114. The lower calf end slot 114 matches the shape of the lower calf near the ankle joint. The posterior calf support 111 is fixedly installed on the rear side of the lower calf end slot 114. The front calf support 112 is hinged to the lower calf end slot 114. The front side of the groove 114 can rotate relative to the calf support 111 to adjust its position to fit the shape of the front side of the human calf; the calf side support 113 is installed on the side of the groove 114 at the lower end of the calf, and the calf side support 113 is provided with an adjustable mechanism 115; the adjustable mechanism 115 is used to adjust the overall length of the corresponding calf side support 113 so that the corresponding universal ball joint 12 is aligned with the rotation center of the human ankle joint; the universal ball joint 12 is fixedly installed at the lower end of the calf side support 113.

[0071] The calf support 11 integrates the rear support, front support, and side support through the calf lower end slot 114, which can closely fit the calf shape of users with different body types. At the same time, the adjustable mechanism 115 achieves precise alignment between the universal ball axis 12 and the rotation center of the human ankle joint, improving assist efficiency and wearing comfort.

[0072] The lower leg slot 114 can be made of high-strength aluminum alloy sheet through CNC bending and welding, forming an open U-shaped frame structure that matches the shape of the lower leg above the ankle joint. The lower leg slot 114 includes a rear slot, a front slot, and a side slot, each configured as a bent mounting lug for connecting the rear lower leg support 111, the front lower leg support 112, and the side lower leg support 113. This provides a unified mounting reference for all components of the lower leg support 11, while also dispersing the local pressure of the exoskeleton on the lower leg.

[0073] The calf support 111 is an arc-shaped plate structure fixedly installed on the mounting ear plate of the rear slot. The calf support 111, the calf side support 113, the calf side slot, and the rear slot are integrally formed. The inner surface of the calf support 111 matches the shape of the muscles on the back of the human calf, providing large-area stable support for the calf. As the main load-bearing component of the calf support 111, it bears the weight of the exoskeleton and the assist torque generated by the drive component 3, and evenly transmits it to the back of the human calf. It achieves lightweight design while ensuring structural strength, and can effectively distribute pressure and improve comfort during long-term wear.

[0074] The calf anterior support 112 is integrally formed with an arc-shaped plate structure and a calf anterior side slot. The calf anterior side slot can be hinged to the mounting ear plate of the calf side slot and can rotate freely around its axis. The inner surface of the calf anterior support 112 matches the shape of the tibia on the front of the human calf, and symmetrical strap mounting holes can be set at the upper end for fixing to the front of the human calf with adjustable straps. The hinged structure enables adaptive adjustment of position, closely conforming to the shape of the front of the calf of users with different calves, adapting to the contraction and relaxation of muscles during exercise, and accommodating calf sizes of users of different body types.

[0075] The lower leg side bracket 113 is an integrally formed long strip plate structure with the posterior groove of the lower leg. The upper end of the lower leg side bracket 113 is provided with a sliding groove structure extending along the length direction for installing the adjustable mechanism 115.

[0076] The adjustable mechanism 115 is located at the upper end of the calf-side support 113 and slides in conjunction with the groove structure of the calf-side support 113, enabling continuous adjustment of the overall length of the calf-side support 113. This allows for personalized adjustments based on the calf length of different users, eliminating installation errors caused by individual differences and ensuring that the exoskeleton's movement trajectory is completely consistent with the natural movement trajectory of the human ankle joint.

[0077] In the wearing process of this embodiment, firstly, the lower calf slot 114 is placed on the lower part of the lower leg above the ankle joint, so that the posterior calf support 111 fits tightly against the posterior side of the lower leg; then, the posterior calf support 112 is rotated to naturally fit against the tibia on the anterior side of the lower leg, and is moderately tightened and fixed by the straps; next, the length of the adjustable mechanism 115 is adjusted so that the center of the universal ball joint 12 is aligned with the tip of the lateral malleolus, and then the adjustable mechanism 115 is locked; finally, the upper end of the lateral calf support 113 is connected to the lower end of the thigh exoskeleton. During movement, the posterior calf support 112 can automatically and slightly adjust its angle according to the contraction and relaxation of the calf muscles, always maintaining a tight fit; the adjustable mechanism 115 can ensure that the universal ball joint 12 is continuously and accurately aligned with the rotation center of the ankle joint, so that the assist torque can be accurately transmitted to the ankle joint.

[0078] This embodiment adopts a split modular calf support 11 structure, combined with a hinged adaptive calf front support 112 and a continuously adjustable calf side support 113, which can adapt to the calf size of users with different heights and body types, making it more comfortable and fit. At the same time, it can ensure that the universal ball axis 12 is precisely aligned with the rotation center of the human ankle joint, avoiding the reduction in assistive efficiency and sports injuries caused by center offset, and significantly improving the assistive effect and safety of the exoskeleton.

[0079] As an optional solution, the adjustable mechanism 115 is located at the end of the lower leg side support 113 away from the ankle joint, forming a groove structure with the lower leg side support 113; the adjustable mechanism 115 includes an adjustable slider 1151 and a locking handle 1152, the adjustable slider 1151 slides in cooperation with the groove structure, and the length adjustment range is 0~75mm; the adjustable slider 1151 is pressed and fixed to the lower leg side support 113 by the locking handle 1152; the upper end of the adjustable slider 1151 is provided with an external thread for fixed connection with the lower end of the thigh exoskeleton, so as to realize the synchronous movement of the lower leg exoskeleton and the thigh exoskeleton.

[0080] The sliding groove structure is a through groove opened along the length of the lower leg side support 113, and is set at the upper end of the lower leg side support 113 away from the ankle joint. The sliding groove structure provides precise sliding guidance and installation reference for the adjustable slider 1151, ensuring straightness and stability during length adjustment.

[0081] The adjustable slider 1151 has a sliding part at its lower end and a connecting part at its upper end. The sliding part of the adjustable slider 1151 is embedded in the slide groove structure, forming a clearance fit with the inner walls on both sides of the slide groove. A transverse through hole is provided in the middle of the adjustable slider 1151 for installing the locking handle 1152, which can be an eccentric wheel type. The adjustable slider 1151 serves as a movable actuator for length adjustment and also provides a connection interface with the thigh exoskeleton, enabling continuous adjustment of the overall length of the lower leg support 113 within the range of 0~75mm to meet the lower leg length requirements of users with different heights from 150cm to 190cm.

[0082] The locking handle 1152 may include a handle body, an eccentric shaft, and two wear-resistant locking washers. The eccentric shaft passes through a transverse through-hole in the middle of the adjustable slider 1151, and its two ends are fixedly connected to the two locking washers, which abut against the outer walls of the slide groove structure on both sides. When the handle body is moved to the locked position, the eccentricity of the eccentric shaft causes the two locking washers to spread outwards, tightly pressing against the outer walls of the slide groove on both sides, thereby fixing the adjustable slider 1151 in any position. The locking handle 1152 enables tool-less, quick locking and releasing of the adjustable slider 1151, shortening the preparation time for wearing.

[0083] The upper part of the adjustable slider 1151 is provided with an external thread connection structure, which can provide a simple and reliable rigid connection method to realize the integrated connection between the lower leg exoskeleton and the thigh exoskeleton, accurately transmit the movement of the thigh exoskeleton to the lower leg exoskeleton, and ensure complete synchronization of the movement of the two.

[0084] This embodiment employs a sliding block precision adjustment structure combined with an eccentric wheel quick-locking mechanism, allowing for length adjustment to cover the lower leg size of most adults, with reliable locking and no slippage. Furthermore, adjustment and locking can be completed without any tools. The standard external thread connection at the upper end is simple and universal, offering high connection strength and good motion synchronization, significantly improving the ease of use and reliability of the exoskeleton.

[0085] As an optional solution, the front calf support 112 includes a front support 1121 and an upper slot 1122; the lower end of the front support 1121 is hinged to the lower calf slot 114, and the upper slot 1122 is fixedly installed on the upper end of the front support 1121, matching the shape of the upper front side of the human calf; the rear calf support 111 includes a rear support 1111 and an upper support plate 1112; the lower end of the rear support 1111 is fixed to the lower calf slot 114, and the upper support plate 1112 is fixedly installed on the upper end of the rear support 1111, matching the shape of the upper rear side of the human calf.

[0086] The front calf support 112 and the rear calf support 111 together form an ergonomic split structure with dual upper and lower support points, which can achieve uniform fit and support throughout the entire calf. This solves the problems of uneven distribution of upper and lower support force, local pressure caused by long-term wear, and easy displacement during exercise in traditional single-segment calf supports 11, further improving wearing comfort and exercise stability.

[0087] The front support 1121 has an overall arc-shaped strip structure, and its lower end can rotate freely around the pin axis. The curvature of the front support 1121 matches the natural curve of the tibia on the front side of the human lower leg. As the middle connecting component on the front side of the lower leg, it connects the lower end slot 114 of the lower leg with the upper slot 1122. At the same time, the hinge structure enables adaptive adjustment of the angle, which can automatically and finely adjust the angle according to the contraction and relaxation of the muscles on the front side of the lower leg, always maintaining a close fit with the lower leg and avoiding loosening or compression of the support due to muscle deformation.

[0088] The upper slot 1122 is an arc-shaped groove structure that matches the shape of the upper front side of the human lower leg, and is fixedly installed on the upper end of the front bracket 1121. The inner surface of the upper slot 1122 can be glued with a slow rebound memory foam pad, and the edges are rounded. There are symmetrical strap mounting ears on both sides for installing adjustable straps. A second support point is formed on the upper front side of the lower leg, forming a double support structure with the lower slot 114. This structure can evenly distribute the weight and assist torque of the exoskeleton on the upper and lower areas of the front side of the lower leg, avoiding pressure sores and poor blood circulation caused by excessive local pressure. At the same time, it significantly improves the overall stability of the bracket and prevents forward and backward displacement during exercise.

[0089] The rear support 1111 has an overall arc-shaped plate structure. The width of the rear support 1111 can cover most of the muscle area on the back of the human calf. The inner surface conforms to the natural contour of the muscles on the back of the calf. As the main load-bearing component on the back of the calf, it bears most of the weight of the exoskeleton and the reverse torque generated by the drive component 3. It can provide large-area stable support for the back of the calf and evenly transmit the assist torque to the entire muscles on the back of the calf, avoiding fatigue and discomfort caused by excessive local stress.

[0090] The upper support plate 1112 is an arc-shaped plate structure that matches the shape of the upper rear side of the human lower leg, and is fixedly installed on the upper end of the rear bracket 1111. The upper support plate 1112 can also be equipped with strap mounting ears on both sides, which work in conjunction with the strap mounting ears of the upper slot 1122. A second support point is formed on the upper rear side of the lower leg, which, together with the upper slot 1122, constitutes a ring-shaped support structure for the upper lower leg. This creates a stable ring-shaped clamp on the upper lower leg, preventing the exoskeleton from shifting up and down or swaying left and right during movement, ensuring precise transmission of the assist torque.

[0091] This embodiment adopts a split lower leg support structure with upper and lower dual support points, which can reduce the maximum local pressure on the lower leg and significantly extend the continuous wearing time; at the same time, the upper and lower ring support structure improves the overall stability of the exoskeleton, avoids displacement and swaying during movement, makes the assistance process more precise and stable, and improves the wearing comfort and user experience of the exoskeleton.

[0092] As an optional solution, the foot support component 2 includes a front foot support 21, a rear foot support 22, and an adjustable locking buckle 23; the front foot support 21 is connected to the rear foot support 22 via the adjustable locking buckle 23; the adjustable locking buckle 23 is used to adjust the distance between the front foot support 21 and the rear foot support 22, and the extension and retraction adjustment range of the adjustable locking buckle 23 is 5~45mm; the foot support component 2 also includes an adjustable strap 24, which is set on the front foot support 21 for fitting and fixing the human foot.

[0093] The forefoot support 21 has an overall U-shaped groove structure with the opening facing upwards, which can completely wrap around the forefoot and the base of the toes. The rear end of the forefoot support 21 is provided with a guide groove extending in the front-to-back direction, and the two sides are symmetrically provided with strap mounting holes. It provides stable support for the forefoot and also serves as the mounting carrier for the adjustable locking buckle 23 and the adjustable strap 24. It can closely conform to the natural contour of the forefoot, distribute foot pressure, and avoid forefoot fatigue and pain caused by prolonged wear.

[0094] The rear foot support 22 has an overall L-shaped structure, capable of supporting both the heel and arch of the foot simultaneously. The upper surface of the rear foot support 22 has a universal ball joint 12 mounting hole, which is fixedly connected to the non-spherical protrusion of the ball joint 122. Near the heel on the rear side of the rear foot support 22, a fisheye bearing 33 hinge seat is located, hinged to the outer ring of the fisheye bearing 33 via a pin. The front end of the rear foot support 22 has a guide slide rod extending in the front-rear direction, forming a sliding engagement with the guide groove at the rear end of the front foot support 21. As the main load-bearing and force-transmitting component of the foot support assembly 2, it bears the weight of the foot and accurately transmits the assist torque generated by the drive assembly 3 to the ankle joint, providing reliable support for the heel and arch, ensuring a clear and accurate transmission path for the assist torque with no energy loss.

[0095] The adjustable locking buckle 23 may include a locking knob, a clamping block, and a scale plate. The locking knob is threaded into a threaded hole on the side of the front foot support 21, and the clamping block is fixed to the end of the locking knob, abutting against the side of the guide slide rod. The scale plate is affixed to the upper surface of the front foot support 21, marking the foot length scale lines. By rotating the locking knob, the clamping force of the clamping block on the guide slide rod can be changed, thereby adjusting and fixing the distance between the front foot support 21 and the rear foot support 22. This allows for continuous and precise adjustment of the foot length, enabling the foot support component 2 to adapt to users with different foot lengths. After locking, there is no loosening or slippage, and it can withstand various impacts and vibrations during exercise.

[0096] The adjustable strap 24 can be configured as a nylon Velcro strap, with both ends threaded through the strap mounting holes on both sides of the forefoot bracket 21 for secure fastening. The inner surface of the strap is lined with a soft fleece layer, while the outer surface is a Velcro hook side. This securely fastens the forefoot within the forefoot bracket 21, preventing relative slippage between the foot and the bracket during movement. The tightness can be freely adjusted according to the user's needs, ensuring reliable fixation without compressing blood vessels in the foot and guaranteeing unobstructed blood circulation.

[0097] This embodiment adopts a split adjustable foot support structure, combined with a quick-locking mechanism with scale markings, which can cover the foot length of most adults, with high adjustment accuracy and reliable locking; at the same time, the ergonomically designed front and rear foot supports 22 can closely fit the natural contour of the foot, distribute foot pressure, significantly improve wearing comfort, and enhance the performance and user experience of the exoskeleton.

[0098] As an optional solution, the forefoot support 21 includes a foot support plate 211, two side plates 212, and an upper plate 213; the two side plates 212 are respectively fixedly installed on both sides of the foot support plate 211, forming a U-shaped structure that conforms to the shape of the foot and surrounds the sides of the foot; the upper plate 213 is fixedly installed on the upper end of the two side plates 212, at a preset angle to the foot support plate 211 to adapt to the height of the human foot; the rearfoot support 22 includes a main plate 221, a first connector 222, a second connector 223, and... Heel baffle 224; one end of the first connector 222 is fixedly connected to the upper end of the main board 221, and the other end is fixedly connected to the protrusion of the ball joint shaft 122; the heel baffle 224 is fixedly installed on the side of the main board 221 away from the front foot bracket 21, for fitting the human heel; the fixed end of the adjustable locking buckle 23 is fixedly connected to the rear end of the two side guards 212 respectively, and the movable end of the adjustable locking buckle 23 is fixedly connected to both ends of the second connector 223 respectively, and the second connector 223 is fixedly installed on the front end of the main board 221.

[0099] The foot support plate 211 has a flat structure that matches the contour of the forefoot, providing uniform bottom support for the forefoot, dispersing foot pressure, and avoiding localized pressure pain and fatigue in the forefoot caused by prolonged wear. At the same time, it provides a stable mounting reference for the side plates 212 and the upper plate 213.

[0100] The two side panels 212 are curved plate-like structures, symmetrically fixed to the left and right sides of the foot support plate 211. The curvature of the two side panels 212 matches the natural contour of the sides of the forefoot, forming an upward-opening U-shaped wrapping structure with the foot support plate 211, covering more than half of the sides of the forefoot. The side panels 212 wrap around the forefoot from both sides to prevent the foot from sliding sideways or rolling over during movement.

[0101] The upper guard plate 213 has an overall arc-shaped plate structure and is fixedly installed on the upper end of the two side guard plates 212. The upper guard plate 213 and the foot support plate 211 form a preset angle of 15° to 20°, which can be statistically designed based on the natural angle between the instep and sole when the human body is standing normally. A slow-rebound memory foam pad can be installed on the lower surface of the upper guard plate 213 to adapt to different users' instep heights. The upper guard plate 213 restricts the vertical movement of the foot from above, forming a three-dimensional wrapping structure together with the foot support plate 211 and the side guard plates 212, thereby further improving the reliability of foot fixation, preventing relative displacement between the foot and the support during exercise, and ensuring the accurate transmission of assist torque.

[0102] The main board 221 is the main load-bearing component of the rear support bracket 22. The upper end of the vertical section of the main board 221 has a first connector 222 mounting hole, the front end of the horizontal section has a second connector 223 mounting hole, and the rear side has a heel plate 224 mounting surface. The main board 221 integrates all the functional components of the rear support bracket 22, forming a unified load-bearing and force-transmitting main body.

[0103] The lower end of the first connector 222 is fixedly installed in the mounting hole at the upper end of the main board 221 through an interference fit and a lock nut; the upper end of the first connector 222 is fixedly connected to the non-spherical protrusion of the ball joint shaft 122. The first connector 222 enables a rigid connection between the rear foot bracket 22 and the universal ball joint 12, transmitting the movement of the rear foot bracket 22 to the universal ball joint 12, thereby ensuring that the rear foot bracket 22 and the universal ball joint 12 rotate synchronously and that the movement transmission is accurate.

[0104] The second connector 223 is a long, strip-shaped plate structure, fixedly installed at the front end of the horizontal section of the main board 221. Both ends of the second connector 223 extend out to the left and right sides of the main board 221, forming two symmetrical connecting ears for connecting to the movable end of the adjustable locking buckle 23. The second connector 223 serves as a connecting bridge between the rear support bracket 22 and the adjustable locking buckle 23, achieving a rigid connection and length adjustment between the rear and rear support brackets 22. It can evenly transmit the locking force of the adjustable locking buckle 23 to both sides of the main board 221, avoiding structural deformation caused by unilateral force and ensuring the stability of length adjustment.

[0105] The heel guard 224 is an arc-shaped plate structure that matches the shape of the human heel and is fixedly installed on the rear side of the main board 221. The heel guard 224 restricts the forward and backward movement of the foot from the rear, while providing comfortable support for the heel. It can prevent the foot from sliding backward when pushing off the ground, ensure that the assist torque can be accurately applied to the ankle joint, and improve wearing comfort.

[0106] The two fixed ends of the adjustable locking buckle 23 are respectively fixedly installed at the rear ends of the two side guard plates 212, and the movable end is hinged to the connecting ears at both ends of the second connector 223 via a pin. By extending and retracting the adjustable locking buckle 23, the distance between the front foot support 21 and the rear foot support 22 can be changed, thereby adjusting the foot length.

[0107] This embodiment improves the reliability of foot fixation by adopting a three-dimensional wrap-around forefoot support 21 structure and a modular rear foot support 22 structure, avoiding foot slippage and lateral rollover during exercise; at the same time, the structure is lighter, the overall weight is reduced, and it is more comfortable to wear; the assist torque is transmitted more evenly and accurately, significantly improving the assist efficiency and safety of the exoskeleton.

[0108] As an optional solution, the lower leg slot 114 is a circular slot structure with a front opening, and the lower leg side brackets 113 are two symmetrically arranged structures; the lower ends of the two lower leg side brackets 113 are respectively fixedly installed on the inner walls of the left and right sides of the circular slot structure, surrounding the human lower leg from both sides; a universal ball shaft 12 is fixedly installed on the lower ends of the two lower leg side brackets 113, and the protruding parts of the ball joints 122 of the two universal ball shafts 12 are respectively fixedly connected to the left and right sides of the foot support component 2; a closing plate is rotatably installed at the front opening of the circular slot structure, and the lower leg front bracket 112 is fixedly installed on the closing plate.

[0109] Two sets of lower leg side supports 113 are symmetrically arranged on the left and right sides of the lower leg. The overall structure is a long strip plate, with the lower ends fixed to the inner walls of the left and right sides of the circular slot structure, surrounding the lower leg from both sides. Each of the two lower leg side supports 113 is equipped with a universal ball joint 12 at its lower end, and the universal ball joint 12 connects to the left and right sides of the rear foot support 22. The dual-side support can evenly distribute the weight of the equipment and the assist torque to both sides of the lower leg, improve the overall rigidity of the support, and effectively resist the impact and vibration during exercise.

[0110] The lower calf groove 114 is a ring-shaped design with an opening at the front, which makes it easy to wear and can accommodate different calf sizes and ankle dimensions. The ring structure can provide all-around wrapping support for the lower calf, evenly distribute the stress load, reduce local pressure discomfort, and maintain a stable wearing posture.

[0111] The closing plate is hinged to the front opening of the slot 114 at the lower end of the calf, allowing for flexible opening and closing. A snap-lock mechanism at the bottom ensures a secure closure, preventing accidental opening during movement. The front calf support 112 is fixedly mounted on the closing plate, adjusting its position synchronously with the opening and closing of the closing plate. This opening and closing structure significantly simplifies the wearing process. Once closed and locked, the connection is secure and gapless, closely conforming to the skin on the front of the calf for optimal support and fit.

[0112] In the assembly process of this embodiment, the two lower leg side supports are first fixed to the inner wall of the slot at the lower end of the lower leg. Then, the universal ball joint, the closing plate, and the front support are assembled and fixed in sequence. Finally, the overall structure is connected to the rear foot support to form a complete structure. When wearing, the closing plate is opened and inserted into the leg. After closing and locking, the position of the support is calibrated so that the center of the universal ball joint coincides with the rotation center of the human ankle joint. During exercise, the two universal ball joints 12 deflect synchronously and in coordination, the forces on both sides of the support are balanced, the annular slot is stably limited, and the exoskeleton can move synchronously with the lower leg.

[0113] This embodiment adopts a double-sided double ball joint support combined with a ring-shaped opening and closing slot structure at the lower end of the lower leg, which significantly improves the overall load-bearing performance and structural rigidity. It is easy and efficient to wear and operate, the force distribution on the legs is more reasonable, and it is less likely to cause pressure fatigue after wearing for a long time. It effectively broadens the applicable scenarios of the exoskeleton and comprehensively improves its overall performance.

[0114] According to another aspect of the invention, a human exoskeleton is also provided, comprising a trunk exoskeleton and at least one lower leg exoskeleton with ankle joint assistance as described above, the lower leg exoskeleton being connected to the trunk exoskeleton.

[0115] The single-joint lower leg exoskeleton of this embodiment can be integrated into a complete human exoskeleton system, relying on multi-joint coordinated drive to complete assisted movements, and can be applied to various scenarios such as industrial handling, military operations, and limb rehabilitation.

[0116] The torso exoskeleton employs a modular structure, primarily comprising a back support module, a lumbar support module, and symmetrically arranged thigh exoskeletons. The back module bears external loads, the lumbar module assists in lumbar flexion and extension, and the two thigh exoskeletons are hinged to the back support, allowing for flexible rotation around the hip joints. Standard docking ports are pre-installed at the lower ends of the thighs for assembling the lower leg exoskeletons. The entire torso structure provides stable support for the lower leg components, coordinating the coordinated force exertion of multiple joints (hip, knee, and ankle) to transfer loads to the ground via the skeletal structure, effectively reducing the pressure on the body's muscles and bones.

[0117] The lower leg exoskeleton and torso exoskeleton employ a universal quick-connect structure, using threaded engagement for a secure fit. Once assembled and locked, the overall connection is robust, with minimal transmission gaps, allowing for precise transmission of limb movements and ensuring coordinated and unified joint actions throughout the body. The modular assembly design facilitates easy disassembly and assembly, enabling flexible replacement of functional components to meet diverse usage needs, thus enhancing the equipment's versatility and expandability.

[0118] In this embodiment, the torso exoskeleton is first worn and fixed, then the exoskeletons of both lower legs are assembled in sequence. After the upper and lower components are connected and locked, the equipment can be put into use after initialization and calibration. When the human body walks or carries weight, the ankle joint assist structure works in sync with the hip and knee joints. It provides dorsiflexion assistance during the leg lift phase and plantarflexion assistance during the push-off phase. Multiple parts work together to smoothly complete various limb movements.

[0119] This embodiment integrates a single lower limb assistive exoskeleton system, effectively increasing the human body's load-bearing capacity and reducing energy consumption during limb movement. Its modular architecture adapts to various usage combinations, and the coordinated movement of multiple joints conforms to the natural activity patterns of the human body. Overall, it boasts excellent performance and is applicable to various fields including industry, military, and rehabilitation.

[0120] 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.

[0121] Furthermore, it should be noted that the use of terms such as "first" and "second" to define components is merely for the purpose of distinguishing the corresponding components. Unless otherwise stated, the above terms have no special meaning and therefore cannot be construed as limiting the scope of protection of this application.

[0122] The above are merely preferred embodiments of this application and are not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A lower leg exoskeleton with ankle joint assistance, characterized in that, include: Lower leg support component (1), foot support component (2), drive component (3); The calf support assembly (1) includes a calf bracket (11) and a universal ball joint (12); the calf bracket (11) is connected to the foot support assembly (2) through the universal ball joint (12); The universal ball joint (12) includes a ball socket bracket (121) and a ball head pivot (122); the ball socket bracket (121) is fixedly installed at the lower end of the lower leg bracket (11), the spherical head of the ball head pivot (122) is embedded in the spherical groove of the ball socket bracket (121), and the protrusion of the ball head pivot (122) is fixedly installed on the foot support assembly (2); The drive assembly (3) includes an electric cylinder (31), an electric cylinder bracket (32), and a fisheye bearing (33); the fixed end of the electric cylinder (31) is hinged to the lower leg bracket (11) through the electric cylinder bracket (32); the output end of the electric cylinder (31) is hinged to the foot support assembly (2) near the back of the foot through the fisheye bearing (33); the fisheye bearing (33) can keep the output axis of the electric cylinder coaxial with the connecting axis of the fisheye bearing, so that the electric cylinder (31) can extend and retract to drive the foot support assembly (2) to rotate around the ball head pivot (122) to realize the dorsiflexion and plantarflexion of the ankle joint.

2. The lower leg exoskeleton with ankle joint assistance according to claim 1, characterized in that, The electric cylinder (31) drives the foot support assembly (2) to rotate around the ball head axis (122) through the electric cylinder bracket (32), so as to achieve a range of motion where the maximum dorsiflexion angle is 35° relative to the neutral position of the ankle joint and the maximum plantarflexion angle is 45° relative to the neutral position of the ankle joint; wherein, the neutral position of the ankle joint refers to the position where the lower leg and the sole of the foot are at 90°; The electric cylinder bracket (32) includes a first rotating shaft (321) and a U-shaped frame (322). The first rotating shaft (321) is fixedly installed on the lower leg bracket (11), and the bottom center of the U-shaped frame (322) is fixedly connected to the first rotating shaft (321) so that the U-shaped frame (322) can rotate around the axis of the first rotating shaft (321); the two free ends of the U-shaped frame (322) are respectively provided with rotating bearings, and the fixed ends of the electric cylinder (31) are respectively connected to the two rotating bearings, so that the electric cylinder (31) can rotate around the axis of the rotating bearings; The axis of the first rotating shaft (321) is perpendicular to the axis of the rotating bearing to ensure that the electric cylinder (31) has no motion interference and no loss of output torque within the full range of motion angles.

3. The lower leg exoskeleton with ankle joint assistance according to claim 1, characterized in that, The ball joint bracket (121) of the universal ball joint (12) has an annular damping ring on its inner wall; The ball socket support (121) is provided with a damping adjustment mechanism for adjusting the clamping force between the annular damping ring and the ball head shaft (122), thereby forming an adjustable damping structure; The universal ball joint (12) enables the foot support component (2) to passively achieve inversion, eversion and rotation around the lower leg axis as the human ankle moves, and to remain stable in any rotation position.

4. The lower leg exoskeleton with ankle joint assistance according to claim 1, characterized in that, The lower leg support (11) includes a posterior lower leg support (111), a front lower leg support (112), and a side lower leg support (113). The posterior lower leg support (111), the front lower leg support (112), and the side lower leg support (113) are all connected to the lower leg end slot (114). The lower leg end slot (114) matches the shape of the part of the human lower leg near the ankle joint. The posterior calf support (111) is fixedly installed on the rear side of the lower calf slot (114); the posterior calf support (112) is hinged to the front side of the lower calf slot (114) and can rotate relative to the posterior calf support (111) to adjust its position to fit the shape of the front side of the human calf. The lower leg side bracket (113) is installed on the side of the lower leg slot (114), and the lower leg side bracket (113) is provided with an adjustable mechanism (115). The adjustable mechanism (115) is used to adjust the overall length of the corresponding lower leg side bracket (113) so that the corresponding universal ball joint (12) is aligned with the rotation center of the human ankle joint; the universal ball joint (12) is fixedly installed at the lower end of the lower leg side bracket (113).

5. The lower leg exoskeleton with ankle joint assistance according to claim 4, characterized in that, The adjustable mechanism (115) is located at the end of the lower leg side support (113) away from the ankle joint, and forms a groove structure with the lower leg side support (113); The adjustable mechanism (115) includes an adjustable slider (1151) and a locking handle (1152). The adjustable slider (1151) slides in conjunction with the slide groove structure, and its length adjustment range is 0~75mm. The adjustable slider (1151) is pressed and fixed to the lower leg side bracket (113) by the locking handle (1152); the upper end of the adjustable slider (1151) is provided with an external thread for fixed connection with the lower end of the thigh exoskeleton, so as to realize the synchronous movement of the lower leg exoskeleton and the thigh exoskeleton.

6. The lower leg exoskeleton with ankle joint assistance according to claim 4, characterized in that, The lower leg anterior support (112) includes a front support (1121) and an upper slot (1122). The lower end of the front bracket (1121) is hinged to the lower end slot (114) of the lower leg, and the upper slot (1122) is fixedly installed on the upper end of the front bracket (1121) to match the shape of the upper front side of the human lower leg. The calf support (111) includes a rear support (1111) and an upper support plate (1112); the lower end of the rear support (1111) is fixed to the lower end slot (114) of the calf, and the upper support plate (1112) is fixedly installed on the upper end of the rear support (1111) to match the shape of the upper rear side of the human calf.

7. The lower leg exoskeleton with ankle joint assistance according to claim 1, characterized in that, The foot support assembly (2) includes a front foot support (21), a rear foot support (22), and an adjustable locking buckle (23). The front foot bracket (21) is connected to the rear foot bracket (22) via the adjustable locking buckle (23); The adjustable locking buckle (23) is used to adjust the distance between the front foot bracket (21) and the rear foot bracket (22), and the extension and retraction adjustment range of the adjustable locking buckle (23) is 5~45mm; The foot support assembly (2) also includes an adjustable strap (24), which is mounted on the forefoot bracket (21) for fitting and fixing the human foot.

8. The lower leg exoskeleton with ankle joint assistance according to claim 7, characterized in that, The forefoot support (21) includes a foot support plate (211), two side guards (212) and an upper guard plate (213); the two side guards (212) are respectively fixedly installed on both sides of the foot support plate (211) to form a U-shaped structure that conforms to the shape of the foot and is used to surround the sides of the foot. The upper guard plate (213) is fixedly installed on the upper end of the two side guard plates (212) at a preset angle to the foot support plate (211) to adapt to the height of the human foot. The rear foot support (22) includes a main board (221), a first connector (222), a second connector (223), and a heel baffle (224); one end of the first connector (222) is fixedly connected to the upper end of the main board (221), and the other end is fixedly connected to the protrusion of the ball joint shaft (122); the heel baffle (224) is fixedly installed on the side of the main board (221) away from the front foot support (21) for conforming to the human heel; The fixed end of the adjustable locking buckle (23) is fixedly connected to the rear end of the two side guard plates (212) respectively, and the movable end of the adjustable locking buckle (23) is fixedly connected to both ends of the second connector (223) respectively. The second connector (223) is fixedly installed on the front end of the main board (221).

9. The lower leg exoskeleton with ankle joint assistance according to claim 4, characterized in that, The lower leg slot (114) is a circular slot structure with an opening on the front side, and the lower leg side bracket (113) consists of two symmetrically arranged structures; The lower ends of the two lower leg side brackets (113) are respectively fixedly installed on the inner walls of the left and right sides of the circular slot structure, surrounding the human lower leg from both sides; A universal ball joint (12) is fixedly installed at the lower end of each of the two lower leg side supports (113), and the protruding parts of the ball joints (122) of the two universal ball joints (12) are fixedly connected to the left and right sides of the foot support assembly (2); A closing plate is rotatably installed at the front opening of the circular slot structure, and the lower leg front bracket (112) is fixedly installed on the closing plate.

10. A human exoskeleton, characterized in that, It includes a trunk exoskeleton and at least one lower leg exoskeleton with ankle assistance as described in any one of claims 1 to 9, the lower leg exoskeleton being connected to the trunk exoskeleton.

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