Knee joint exoskeleton power assisting device

Abstract

The knee joint exoskeleton power assisting device comprises a thigh assembly and a shank assembly rotationally connected with the thigh assembly, and is characterized in that a driving module is arranged on the front face of the thigh assembly, the driving module is connected with the shank assembly through a flexible transmission assembly, and the driving module comprises a containing piece capable of rotating forwards and backwards; one end of the flexible transmission assembly is connected with the storage piece and can be wound on the storage piece. The knee joint exoskeleton power assisting device is worn right in front of the knee of the human body, inertia of moving parts can be effectively reduced, man-machine compatibility and wearing comfort are improved, and efficient and accurate power assisting is achieved through an optimized transmission and fixing structure.

Description

Technical Field

[0001] This invention relates to the field of exoskeleton robot technology, and in particular to a knee joint exoskeleton assistive device. Background Technology

[0002] Exoskeleton robots are human-machine integrated systems that integrate sensing technology, control technology, information technology, and mobile computing technology. They are enhanced by coupling mechanical structures with human joints and can perform functions and tasks such as assisted walking under the unconscious control of the user. Among the many exoskeleton robots, exoskeleton assistive devices for knee joint assistance are extensively studied.

[0003] Traditional exoskeleton assistive devices use a motor to directly drive a rigid structure of the knee joint hinge via a reducer. This type of knee exoskeleton assistive device has the following drawbacks:

[0004] (1) Heavy weight and large inertia: The motor and reducer are concentrated on the outside of the leg, resulting in a large moment of inertia. The pendulum effect will be generated at the end of the swing phase, which will hinder the natural swing of the human leg and increase the user's energy consumption.

[0005] (2) Human-machine alignment is difficult to achieve: Traditional rigid exoskeleton assistive devices achieve rotation through rigid hinges, but the fixed rotation center of the rigid hinge is difficult to perfectly match the instantaneous change of the rotation center of the human knee joint. The rigid hinge will exert unnecessary restraint on the human knee joint, affecting the comfort of wearing.

[0006] (3) Inconvenient to wear: The rigid exoskeleton assistive device with transmission is relatively large in size, and wearing and adjusting it is relatively cumbersome.

[0007] To overcome the above problems, existing technologies include flexible exoskeletons that use flexible cable components such as Bowden wires, such as patent CN115502958A, which describes a knee-assisted flexible exoskeleton based on Bowden wire transmission. One end of the Bowden wire is connected to the power output device in the waist, and the other end is connected to the knee joint actuator. However, Bowden wires have problems such as a large bending radius, significant internal friction loss, and low pushing efficiency during the return stroke, which affect the assist efficiency and response speed. Summary of the Invention

[0008] The purpose of this invention is to provide a knee joint exoskeleton assistive device. On the one hand, it solves the problems in the prior art where the flexible exoskeleton drive module is located at the waist and connected to the lower leg exoskeleton via Bowden wire, which not only causes a large bending radius of the Bowden wire and significant frictional loss, but also results in low push-line efficiency during the return stroke, thus affecting the assistive efficiency and response speed. On the other hand, by setting the entire knee joint exoskeleton assistive device from the outside of the leg to the front of the calf and thigh, it reduces the weight load on the leg and improves wearing comfort.

[0009] The present invention is implemented as follows: The present invention provides a knee joint exoskeleton assistive device, including a thigh component and a lower leg component rotatably connected to the thigh component. The front of the thigh component is provided with a drive module. The drive module is connected to the lower leg component through a flexible transmission component. The drive module includes a reversible storage component. One end of the flexible transmission component is connected to the storage component and can be wrapped around the storage component. The end of the lower leg component connected to the flexible transmission component is higher than the rotatable connection point between the thigh component and the lower leg component.

[0010] In existing technologies, to overcome the problems caused by placing the motor on the side of the calf, the motor is placed in the waist and a Bowden cable is used as the transmission component. However, the Bowden cable has problems such as a large bending radius, significant internal friction loss, and low cable pushing efficiency during the return stroke, which affect the assist efficiency and response speed. The drive module of this application is placed on the front of the thigh component, which will not affect the user's squatting movements or hinder the user's natural swing. Moreover, the drive module is located on the front of the thigh component, which is closer to the center of motion in the sagittal plane of the human body. This helps to reduce lateral sway and inertial resistance during movement, making the movement feel more natural. Furthermore, the length of the flexible transmission component used to connect the drive module and the calf component is greatly shortened, which can avoid friction loss and greatly improve the assist efficiency and response speed.

[0011] As a preferred embodiment, the flexible transmission assembly includes a high-strength flexible webbing and a guide mechanism. One end of the high-strength flexible webbing is connected to the drive module, and the other end is connected to the lower leg assembly through the guide mechanism.

[0012] The flexible transmission component in this application can achieve transmission using a high-strength flexible webbing, avoiding the friction loss problem caused by using Bowden wire. To ensure that the high-strength flexible webbing can smoothly change direction and extend to the lower leg after exiting the drive module, one end of the high-strength flexible webbing is connected to the lower leg assembly through a guide mechanism.

[0013] As a preferred embodiment, the thigh assembly is provided with mounting holes or mounting slots, and the drive module is detachably fixed to the front of the thigh assembly through the mounting holes or mounting slots.

[0014] The drive module can be detachably fixed to the surface of the thigh component, and can be fixed in an appropriate position on the thigh based on the user's height and weight. It can be installed in a suitable position according to the user's specific height and weight, and can match the user's height and weight to move, thus improving the naturalness of the movement process.

[0015] As a preferred embodiment, the high-strength flexible webbing is a flat webbing woven from at least one of Dyneema fiber or silicon carbide fiber.

[0016] The high-strength flexible webbing of this invention is a flat webbing woven from high-strength fibers. Compared with round steel wire rope, the flat webbing is less likely to overlap and jam when wound, has a large contact area, uniform pressure distribution, longer service life, and has extremely high tensile strength, excellent flexibility and wear resistance, and is extremely lightweight.

[0017] As a preferred embodiment, the guiding mechanism is a guide ring or a guide wheel, and the guide wheel is preferably a pulley or a pulley block.

[0018] As a preferred embodiment, the drive module includes a motor, a reducer, and a reel connected in sequence, with one end of the flexible transmission component wound around the reel and the other end of the flexible transmission component connected to the lower leg component.

[0019] One end of the flexible transmission component is connected to the reel, and the other end is connected to the calf component. By rotating the motor in both directions, the reel can adjust the length of the flexible transmission component in a timely manner according to the distance between the thigh component and the calf component.

[0020] As a preferred embodiment, the rope groove of the reel is designed as an involute rope groove or a recess. In a further preferred embodiment, the recess is a curvature recess, the bottom curvature of the curvature recess is close to 0, and the sidewall curvature radius of the curvature recess is 5~30mm.

[0021] The reel's cord groove is designed as an involute groove or recess to optimize the winding of high-strength flexible webbing and prevent overlap and wear.

[0022] As a preferred embodiment, the thigh assembly and the lower leg assembly are connected by a human-machine compatible joint structure.

[0023] Human-machine compatible joint structures enable the thigh and lower leg components to be connected without rigid hinges, allowing for slight relative movement between the exoskeleton assist device and the human knee joint in the sagittal plane, thereby reducing movement constraints.

[0024] In a further preferred embodiment, the human-machine compatible joint structure is a multi-hinge structure or a multi-degree-of-freedom structure.

[0025] The human-machine compatible joint structure adopts a multi-hinge structure or a multi-degree-of-freedom structure, which can achieve the connection between the thigh and lower leg components without affecting the compression of the joint. The multi-degree-of-freedom structure allows for small relative movements between the exoskeleton assist device and the human knee joint in the sagittal plane, thereby reducing movement constraints.

[0026] As a preferred embodiment, the thigh assembly includes a thigh fixation plate (and an adjustable strap, the thigh fixation plate and the adjustable strap forming a thigh binding area for binding the thigh, the adjustable strap being detachably connected to the thigh fixation plate).

[0027] As a preferred embodiment, the calf assembly includes a calf fixation kit and a connector. The calf fixation kit is provided with an adjustable binding strap, and the connector is slidably mounted on the calf fixation kit.

[0028] In a further preferred embodiment, the end of the connector is higher than the human-machine compatible joint structure.

[0029] When bending occurs at the hinge of the thigh and calf, the flexible transmission component remains straight and does not require bending, reducing the use of parts that guide the flexible transmission component, avoiding friction of the flexible transmission component, and improving the service life of the device.

[0030] The beneficial effects of this invention are:

[0031] (1) This invention discloses a knee joint exoskeleton assistive device, providing a knee joint assistive solution that is lightweight, has low inertia, good human-machine compatibility, and high transmission efficiency. The assistive device is worn in front of the human knee, which can effectively reduce the inertia of moving parts, improve human-machine compatibility and wearing comfort, and achieve efficient and precise assistance through optimized transmission and fixing structure.

[0032] (2) The knee joint exoskeleton assist device provided by the present invention is a direct-drive knee joint exoskeleton assist device, which is worn in front of the thigh. Through the cooperation of the various structures of the device, it can achieve assistance based on the normal walking motion of the human body. When the user walks, the flexible transmission component is extended and retracted by the drive module, thereby realizing that the lower leg component matches the movement arc of the lower leg and rotates around the thigh component, which improves human-machine compatibility and wearing comfort.

[0033] (3) The drive module of the present invention is located on the front of the thigh component, which is closer to the center of motion in the sagittal plane of the human body. This helps to reduce lateral sway and inertial resistance during movement, making the movement feel more natural. In addition, inertial optimization is achieved. The present invention places the heavier drive module at the proximal end of the thigh, which significantly reduces the swaying inertia of the lower leg, making the gait more natural and the user more convenient to walk after wearing it.

[0034] (4) High-efficiency transmission: The combination of drive module and flexible transmission component adopted in this invention results in lower friction loss during transmission than Bowden wire. In particular, it can quickly return to its original position by relying on the flexibility of the high-strength flexible webbing itself during the return stroke. It has good responsiveness, high tensile strength, light weight and small bending radius.

[0035] (5) The flexible transmission component in this invention is not resistant to pressure or bending, but only transmits tension. It does not generate unnecessary lateral force on the limbs, which greatly improves the wearing comfort.

[0036] (6) Modularization and lightweighting are achieved: The direct-drive knee exoskeleton assistive device provided by the present invention has a modular structure between its components, which is easy to design, replace and assemble. Attached Figure Description

[0037] Figure 1 This is a left view of a knee exoskeleton assistive device in the extended state according to Embodiment 1;

[0038] Figure 2 This is a left view of a knee exoskeleton assistive device in embodiment 1 with the knee in a flexed position;

[0039] Figure 3 This is a perspective view of a knee exoskeleton assistive device in the extended state according to Embodiment 1;

[0040] Figure 4 This is a perspective view of a knee joint exoskeleton assistive device in the flexed knee position, as described in Embodiment 1.

[0041] Figure 5 This is a schematic diagram of the drive module in a knee exoskeleton assistive device according to Embodiment 1;

[0042] Figure 6 This is a schematic diagram of the human-machine compatible joint structure in Example 2.

[0043] Attached image label: 10, Thigh assembly;

[0044] 20. Drive module; 21. Motor; 22. Reducer; 23. Reel;

[0045] 30. Flexible transmission components; 32. Guiding mechanisms;

[0046] 40. Lower leg assembly; 42. Connector;

[0047] 50. Human-machine compatible joint structure; 3. Connecting holes. Detailed Implementation

[0048] The following specific examples 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. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention.

[0049] Example 1:

[0050] like Figures 1 to 6As shown, this embodiment provides a knee joint exoskeleton assistive device, including a thigh component 10, a drive module 20, a flexible transmission component 30, a lower leg component 40, and a human-machine compatible joint structure 50. The thigh component 10 is rotatably connected to the lower leg component 40 through the human-machine compatible joint structure 50. One end of the flexible transmission component 30 is wound around the drive module, and the other end is connected to the lower leg component 40. The drive module 20 is fixed directly above the thigh component 10. The drive module 20 can drive the flexible transmission component 30 to extend and retract, thereby causing the lower leg component 40 to rotate around the thigh component 10. The end of the lower leg component 40 connected to the flexible transmission component 30 is higher than the rotatable connection point between the thigh component 10 and the lower leg component 40.

[0051] This embodiment provides a knee joint exoskeleton assistive device fixed directly above the front of the thigh. Through the cooperation of the various structures of the device, it can provide assistance based on the normal walking motion of the human body. When the user walks, the drive module drives the flexible transmission component to extend and retract, thereby enabling the lower leg component to rotate around the thigh component in accordance with the movement arc of the lower leg. It can provide direct-drive assistance according to the user's actual walking posture and walking direction. Moreover, the assistive device is tied to the thigh, which does not increase the load on the lower leg, thus improving human-machine compatibility and wearing comfort.

[0052] In this embodiment, the flexible transmission component 30 includes a high-strength flexible webbing 31 and a flat webbing 31 woven from Dyneema fibers. Compared with round steel wire ropes, the flat webbing woven from Dyneema fibers is less prone to overlapping and jamming during winding, has a larger contact area, more uniform pressure distribution, longer service life, and possesses extremely high tensile strength, excellent flexibility and wear resistance, while being extremely lightweight.

[0053] In this embodiment, the thigh component is provided with mounting holes, and the drive module can be detachably fixed to the front of the thigh component through the mounting holes.

[0054] The drive module can be detachably fixed to the surface of the thigh component, and can be fixed in an appropriate position on the thigh based on the user's height and weight. It can be installed in a suitable position according to the user's specific height and weight, and can match the user's height and weight to move, thus improving the naturalness of the movement process.

[0055] In this embodiment, the thigh assembly 10 includes a thigh fixing plate and an adjustable strap connected thereto. The adjustable strap is connected to the thigh fixing plate through a connecting hole 3. The thigh fixing plate is used to conform to the contour of the user's thigh for fixation. In practical applications, the connecting hole can be replaced with a movable buckle structure, and the adjustable strap can adjustably fix the thigh assembly to the user's thigh through the movable buckle. The thigh assembly is used to fix the entire exoskeleton assistive device to the front of the user's thigh and match the contour of the user's thigh. The thigh fixing plate 11 can be set as any one of an arc structure, a semi-circular structure, or a polygonal curved surface structure. In this embodiment, the thigh fixing plate adopts an arc structure.

[0056] In this embodiment, the drive module 20 includes a motor 21, a reducer 22 and a reel 23 connected in sequence. One end of the flexible transmission component 30 is wound around the reel 23 and the other end is connected to the lower leg component 40. During wear and use, the output torque of the motor 21 is amplified by the reducer 22 and drives the reel 23 to rotate in both directions, thereby driving the flexible transmission component to perform stretching motion.

[0057] In this embodiment, the reel used is as follows: Figure 5 As shown, the slot of the reel is set as a curvature groove. The curvature of the bottom of the curvature groove is close to 0, and the curvature radius of the side wall of the curvature groove is 30mm. Through the slot design of the curvature groove, the winding of high-strength flexible webbing can be optimized to prevent overlap and wear.

[0058] In this example, guide mechanism 32 is a low-friction guide ring. The guide mechanism is used to guide the high-strength flexible webbing to ensure that the high-flexibility webbing can smoothly change direction and extend to the lower leg.

[0059] In this example, the calf assembly 40 includes a calf fixation kit and a connector 42. The calf fixation kit is used to fix the calf assembly to the user's calf, and the connector 42 is used to fix the flexible transmission assembly 30 to the calf assembly 40.

[0060] The lower leg assembly 40 has connection holes 3 on both sides, and adjustable straps for binding the lower leg to the user are connected to the connection holes 3. In practical applications, the connection holes can be replaced with a movable buckle structure, and the adjustable straps can be used to adjust and fix the lower leg assembly to the user's lower leg.

[0061] The connector 42 can also be slidably mounted on the lower leg assembly 40 to adapt to different leg lengths and initial tension requirements. In specific applications, both the thigh assembly 10 and the lower leg assembly 40 are axisymmetric structures, and the axis of symmetry of the thigh assembly 10 and the lower leg assembly 40 coincide when the thigh assembly 10 is in the vertically open state.

[0062] Working principle:

[0063] When assistance is needed (such as at the end of the stance phase in the gait cycle or when climbing stairs), the motor 21 of the drive module rotates, and the reel 23 retracts the high-strength flexible webbing 31. The high-strength flexible webbing 31 transmits the tension to the lower leg connection point through the guide mechanism 32, thereby generating a backward and upward lifting force on the lower leg, assisting in knee flexion and reducing the burden on the thigh muscles. When release is needed, the motor reverses, and the high-strength flexible webbing is pulled out with the assistance of human movement or elastic elements.

[0064] Example 2:

[0065] The overall structure is consistent with Embodiment 1, the difference being the ergonomic joint structure. For example... Figure 6 As shown, in this example, the human-machine compatible joint structure 50 is a 4-branch hinge structure with 1 degree of freedom, which can fit the protruding structure of the user's joint more closely.

[0066] The human-machine compatible joint structure in this example is a floating connection structure with one degree of freedom, which enables a non-rigid hinge between the thigh and lower leg components. This allows for slight relative movement between the exoskeleton assist device and the human knee joint in the sagittal plane, thereby reducing motion constraints.

[0067] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A knee joint exoskeleton assistive device, comprising a thigh assembly (10) and a lower leg assembly (40) rotatably connected to the thigh assembly (10), characterized in that: The thigh assembly (10) has a drive module (20) on its front side. The drive module (20) is connected to the calf assembly (40) through a flexible transmission component (30). The drive module (20) includes a reversible storage component. One end of the flexible transmission component (30) is connected to the storage component and can be wrapped around the storage component. The end of the calf assembly (40) connected to the flexible transmission component (30) is higher than the rotational connection point between the thigh assembly (10) and the calf assembly (40).

2. The knee joint exoskeleton assistive device according to claim 1, characterized in that: The flexible transmission assembly (30) includes a high-strength flexible webbing and a guide mechanism (32). One end of the high-strength flexible webbing is connected to the drive module (20), and the other end is connected to the lower leg assembly (40) through the guide mechanism (32).

3. The knee joint exoskeleton assistive device according to claim 2, characterized in that: The guiding mechanism (32) is a guide ring or a guide wheel.

4. The knee joint exoskeleton assistive device according to claim 1, characterized in that: The drive module (20) includes a motor (21), a reducer (22) and a reel (23) connected in sequence. One end of the flexible transmission component (30) is wound around the reel (23), and the other end is connected to the lower leg component (40).

5. The knee joint exoskeleton assistive device according to claim 4, characterized in that: The rope groove of the reel is an involute rope groove or a recess, the recess is a curvature recess, the bottom curvature of the curvature recess is close to 0, and the sidewall curvature radius of the curvature recess is 5~30mm.

6. The knee joint exoskeleton assistive device according to claim 1, characterized in that: The thigh assembly (10) and the lower leg assembly (40) are connected by a human-machine compatible joint structure (50).

7. The knee joint exoskeleton assistive device according to claim 6, characterized in that: The human-machine compatible joint structure (50) is a multi-hinge structure or a multi-degree-of-freedom structure.

8. The knee joint exoskeleton assistive device according to claim 1, characterized in that: The thigh assembly (10) includes a thigh fixing plate and an adjustable strap, the thigh fixing plate and the adjustable strap forming a thigh binding area for binding the thigh, and the adjustable strap is detachably connected to the thigh fixing plate.

9. A knee joint exoskeleton assistive device according to claim 6, characterized in that: The lower leg assembly (40) includes a lower leg fixation kit and a connector (42). The lower leg fixation kit is provided with an adjustable binding strap, and the connector (42) is slidably disposed on the lower leg fixation kit.

10. A knee joint exoskeleton assistive device according to claim 9, characterized in that: The end of the connector (42) is higher than the human-machine compatible joint structure (50).

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