An ankle exoskeleton that assists and enhances joint stability

Abstract

This invention provides an ankle exoskeleton that assists and enhances joint stability. A wearable component is worn on the wearer's lower leg, and a wearable support is worn on the sole of the wearer's foot. A sliding mechanism and a telescopic component provide assistance and a wrapping force to the ankle joint, with the wrapping force acting as a stabilizing force. The exoskeleton includes: a wearable component, a wearable support, a sliding mechanism, a telescopic component, and a transmission cable. The sliding mechanism is connected to the rear of the wearable support. The transmission cable passes through the telescopic component, around the sliding mechanism, and then exits from the telescopic component. When the wearable component and wearable support are worn around the wearer's ankle joint, the other end of the transmission cable receives a driving force, which is transmitted to the bottom of the ankle joint, providing assistance. This also causes the second and fourth telescopic ends to move away from each other, causing the wearable component to contract and provide a wrapping force to the ankle joint. This invention can provide stable push-off assistance to the ankle joint and increase ankle joint stability during push-off.

Description

Technical Field

[0001] This invention belongs to the field of lower limb exoskeleton robots, and more specifically, relates to an ankle exoskeleton that assists and enhances joint stability. Background Technology

[0002] The complex contact surfaces of the ankle joint mean that its axis is not perfectly perpendicular to the sagittal plane. Current internationally advanced ankle exoskeletons use spring-loaded ratchet wheels or Bowden's lines to apply auxiliary force between the posterior side of the foot brace and the upper middle part of the lower leg, driving the foot to rotate around the ankle joint to assist walking. However, this assistance method creates an additional torque on the ankle joint in the non-driving direction, leading to a tendency for inversion. Excessive inversion accounts for the vast majority of ankle sprains. Therefore, this assistance method may cause hidden injuries to the ankle joint and pose a potential risk to ankle joint stability. Summary of the Invention

[0003] In view of the shortcomings of the prior art, the purpose of this invention is to provide an ankle exoskeleton that assists and enhances joint stability, aiming to solve the problem that existing ankle joint assist methods may cause hidden damage to the ankle joint and pose potential risks to ankle joint stability.

[0004] To achieve the above objectives, the present invention provides an ankle exoskeleton that assists and enhances joint stability. The wearable component is worn on the wearer's lower leg, and the wearable bracket is worn on the wearer's foot. The sliding mechanism and the telescopic component respectively provide assistance and wrapping force to the ankle joint, with the wrapping force serving as a stabilizing force for the ankle joint.

[0005] Specifically, the ankle exoskeleton includes: wearable components, wearable support, sliding mechanism, telescopic parts, and drive cable;

[0006] The wearable device and wearable support are for the wearer to wear outside the ankle joint;

[0007] The first telescopic end of the telescopic component is fixedly connected to one end of the transmission rope, the second telescopic end is connected to one end of the wearable component, the third telescopic end is passed through by the other end of the transmission rope, and the fourth telescopic end is connected to the other end of the wearable component.

[0008] The sliding mechanism is connected to the rear side of the wearable bracket, and the other end of the transmission rope passes through the third telescopic end and around the sliding mechanism, and then passes out from the third telescopic end and the first telescopic end in sequence;

[0009] When the wearable device is worn around the wearer's ankle joint and the wearable bracket is worn at the bottom of the wearer's ankle joint, the other end of the transmission cord is driven by a driving force, which is transmitted to the bottom of the wearer's ankle joint to provide assistance to the wearer's ankle joint. The driving force also causes the first and third telescopic ends of the telescopic component to move closer to each other and the second and fourth telescopic ends to move further apart, so as to cause the wearable device to contract and stretch the ankle joint to provide a wrapping force to the wearer's ankle joint.

[0010] Optionally, the line segment formed by connecting the second and fourth telescopic ends of the telescopic component is parallel to the cross-section of the ankle joint, and the line segment formed by connecting the first and third telescopic ends is perpendicular to the cross-section of the ankle joint.

[0011] Optionally, the retractable component includes: a limiting component;

[0012] The limiting component is located on the frame of the retractable component and is used to limit the degree of retractable deformation of the retractable component, so as to limit the length of the wearable component that is shrunken.

[0013] Optionally, the retractable component includes: four side frames and four connectors;

[0014] The first connector connects one end of the first frame to one end of the fourth frame;

[0015] The second connector connects the other end of the first frame and one end of the second frame;

[0016] The third connector connects the other end of the second frame to one end of the third frame;

[0017] The fourth connector connects the other end of the third frame to the other end of the fourth frame;

[0018] The frame can rotate relative to the connectors it is connected to, and the first to fourth connectors correspond to the first to the fourth telescopic ends, respectively.

[0019] Optionally, each of the first to fourth connectors includes a connecting shaft and a central shaft;

[0020] The central shaft is fixed to the connecting shaft;

[0021] The connecting shaft is used to connect the frame, and the frame can rotate relative to the connecting shaft;

[0022] The central shafts of the first and third connectors are provided with through holes for the transmission rope to pass through;

[0023] The central axis of the second and fourth connectors is used to connect the two ends of the wearable device.

[0024] Optionally, when the frame lengths of the retractable components are the same, let the frame length be L, the initial angle between the frame of the retractable component and the cross-section of the ankle joint be θ0, and the angle between the frame of the retractable component and the cross-section of the ankle joint when the retractable component is deformed to its maximum extent be θ1, then:

[0025] The maximum contraction length ΔL of the transmission rope after being subjected to driving force and the maximum contraction length ΔL of the wearable device a for:

[0026] △L=4L(sinθ0-sinθ1)

[0027] △L a =2L(cosθ1-cosθ0).

[0028] Specifically, the wrapping force is proportional to the contracted length of the wearable device.

[0029] Optionally, the exoskeleton further includes: a drive mechanism;

[0030] The drive mechanism is used to provide driving force to the transmission rope.

[0031] Optionally, the sliding mechanism is a pulley.

[0032] Optionally, the transmission rope is a steel wire rope.

[0033] Optionally, the exoskeleton further includes: another wearable component for being worn around the wearer's lower leg; the other end of the drive rope passes through the first telescopic end, through the other wearable component, and then connects to the drive mechanism.

[0034] Specifically, another wearable component could be a clamp.

[0035] It should be noted that when the wire rope is wrapped in a Bowden line sleeve, the transmission rope can also be called a Bowden line.

[0036] Optionally, the wearable component is a strap.

[0037] In a specific example, a wearable support could be a shoe sole support, which is worn and secured to the sole of a shoe by the wearer.

[0038] Furthermore, wearable supports can also be specially designed shoes with a sliding mechanism fixed at the back, and the size is suitable for the wearer's feet.

[0039] In summary, the technical solutions conceived by this invention have the following beneficial effects compared with the prior art:

[0040] This invention provides an ankle exoskeleton that assists and enhances joint stability. The wearable component is worn on the wearer's lower leg, and the wearable support is worn on the sole of the wearer's foot. A sliding mechanism and a telescopic component provide assistance and a wrapping force to the ankle joint, with the wrapping force serving as a stabilizing force. Therefore, this invention can adjust the magnitude of the assistance and stabilizing force in real time during the gait cycle, thereby wrapping the ankle joint during assistance, providing a protective effect, reducing instability factors, and improving ankle joint stability. Attached Figure Description

[0041] Figure 1 This is an architectural diagram related to the ankle exoskeleton provided in an embodiment of the present invention;

[0042] Figure 2 This is a side view of the ankle exoskeleton structure provided in an embodiment of the present invention;

[0043] Figure 3 This is an exploded view of the rhomboid mechanism provided in an embodiment of the present invention;

[0044] Figure 4 This is a schematic diagram of the initial state of the rhomboid mechanism provided in an embodiment of the present invention;

[0045] Figure 5 This is a schematic diagram of the rhomboid mechanism under maximum deformation according to an embodiment of the present invention;

[0046] In all the accompanying drawings, the same reference numerals are used to denote the same elements or structures, wherein: 1 is a shoe sole support, 2 is a shoe sole pulley, 3 is a rhomboid mechanism, 4 is a calf clamp, 5 is a Bowden line, 6 is a motor, 7 is a motor support, 301 is a retaining ring, 302 is a frame, 303 is a limiting component, 304 is a perforated connector, and 305 is a cylindrical connector. Detailed Implementation

[0047] For ease of understanding, the English abbreviations and related technical terms used in the embodiments of the present invention will be explained and described below.

[0048] The embodiments of the present invention will now be described with reference to the accompanying drawings.

[0049] This invention provides an ankle exoskeleton that assists and enhances joint stability, comprising: a wearable component, a wearable support, a sliding mechanism, a telescopic component, and a transmission cable;

[0050] The wearable device and wearable support are for the wearer to wear outside the ankle joint; the first telescopic end of the telescopic component is fixedly connected to one end of the transmission rope, the second telescopic end is connected to one end of the wearable device, the third telescopic end is passed through by the other end of the transmission rope, and the fourth telescopic end is connected to the other end of the wearable device; the sliding mechanism is connected to the rear side of the wearable support, and the other end of the transmission rope passes through the third telescopic end and around the sliding mechanism, and then passes out from the third telescopic end and the first telescopic end in sequence;

[0051] When the wearable device is worn around the wearer's ankle joint and the wearable support is worn at the bottom of the wearer's ankle joint, the other end of the transmission cord is driven by a driving force, which is transmitted to the bottom of the wearer's ankle joint to provide assistance to the wearer's ankle joint. The driving force also causes the first and third telescopic ends of the telescopic component to move closer to each other and the second and fourth telescopic ends to move further apart, so that the wearable device contracts to provide a wrapping force to the wearer's ankle joint.

[0052] Optionally, the line segment formed by connecting the second and fourth telescopic ends of the telescopic component is parallel to the cross-section of the ankle joint, and the line segment formed by connecting the first and third telescopic ends is perpendicular to the cross-section of the ankle joint.

[0053] Optionally, the retractable component includes a limiting component; the limiting component is located on the frame of the retractable component and is used to limit the degree of retraction and deformation of the retractable component, so as to limit the length of the wearable component that is retracted.

[0054] Optionally, the retractable component includes: four frame edges and four connectors; a first connector connects one end of the first frame edge and one end of the fourth frame edge; a second connector connects the other end of the first frame edge and one end of the second frame edge; a third connector connects the other end of the second frame edge and one end of the third frame edge; a fourth connector connects the other end of the third frame edge and the other end of the fourth frame edge; wherein the frame edge is rotatable relative to the connectors it is connected to, and the first to fourth connectors correspond to the first to the fourth retractable ends, respectively.

[0055] Furthermore, when the four sides of the retractable component are of the same length, the retractable component can also be called a rhombus mechanism.

[0056] Optionally, the exoskeleton further includes: another wearable component for being worn around the wearer's lower leg; the other end of the drive rope passes through the first telescopic end, through the other wearable component, and then connects to the drive mechanism.

[0057] Specifically, another wearable component can be achieved through a clamp.

[0058] Furthermore, wearable components can be achieved through straps. Wearable supports can be achieved through shoe sole supports. Straps are used to secure the device near the wearer's ankle, while the shoe sole supports are used to secure it to the bottom of the wearer's shoe.

[0059] Furthermore, the transmission rope can be made of steel wire rope.

[0060] Understandably, existing advanced ankle exoskeletons internationally employ spring ratchet or Bowden wires to apply auxiliary force between the posterior side of the foot brace and the upper middle part of the lower leg, driving the foot to rotate around the ankle joint to assist walking. The complex contact surfaces of the ankle joint mean that the ankle joint axis is not perfectly perpendicular to the sagittal plane, resulting in a misalignment between the ankle joint axis and the direction of the auxiliary force. This increases the torque in the non-driving direction of the ankle joint, posing a potential risk to ankle joint stability. The purpose of this invention is to design an active ankle joint assistive exoskeleton that enhances stability. A single steel wire rope not only provides plantar flexion assistance to the ankle joint but also provides a stable wrapping force around the ankle joint, enhancing ankle joint stability. Furthermore, the magnitude of the wrapping force can be freely adjusted by changing the installation position of the diamond-shaped mechanism's limiting component.

[0061] In a specific embodiment, such as Figure 1 As shown and Figure 2 As shown, the ankle exoskeleton provided by this invention includes: a sole support 1, a sole pulley 2, a rhomboid mechanism 3, a calf clamp 4, a Bowden cable 5, a motor 6, and a motor support 7. One end of the Bowden cable 5 is fixed to the connector of the rhomboid mechanism 3, passes around the pulley of the sole support 1, passes through the through hole of the rhomboid mechanism 3, enters the sleeve of the Bowden cable 5 at the calf clamp 4, and finally connects to the shaft of the motor 6. The sole support 1 is fixed to the wearer's sole, and the calf clamp 4 is bound to the wearer's calf via a calf strap. The tension generated by the motor 6 pulling the Bowden cable 5 acts on the cable support. This tension, after passing through the cable support, acts on the central shaft of the sole pulley and is transmitted to the wearer's heel, providing assistance for the wearer's movement. It is also transmitted to the horizontal strap of the rhomboid mechanism 3, where the tightening strap provides a protective wrapping force to the ankle joint.

[0062] It should be noted that, as Figure 1 The drive mechanism shown can be implemented by motor 6. It is understood that in the actual use stage of the ankle exoskeleton, the drive mechanism can be implemented by other devices besides motor, and the drive mechanism, once designed, can be carried or worn by the wearer to meet the ankle joint assistance needs during the wearer's free movement or walking.

[0063] This invention allows a single steel wire rope to simultaneously provide assistance and stability to the ankle joint. Its core component, the diamond-shaped mechanism, provides a wrapping force to the ankle joint during assistance, thus stabilizing and protecting it.

[0064] Figure 3 This is an exploded view of the rhomboid mechanism provided in an embodiment of the present invention, as shown below. Figure 3 As shown, the assembly includes: a retaining ring 301, a frame 302, a limiting component 303, a perforated connector 304, and a cylindrical connector 305. Two perforated connectors 304 and two cylindrical connectors 305 are included, each comprising a connecting shaft and a central shaft. Each connecting shaft connects two frames 302. A through hole is provided on the central shaft of the perforated connector 304 for the steel wire rope of the Bowden line 5 to pass through. The cylindrical connector 305 connects the two ends of the strap. The limiting component 303 is placed on the frame 302. The retaining ring 301 is placed on top of the perforated connector 304 and the cylindrical connector 305 to secure the two frames 302.

[0065] Furthermore, the frame 302 can rotate relative to the connector, thereby realizing the telescoping function of the rhomboid mechanism.

[0066] It should be noted that the horizontal plane of the rhomboid mechanism is parallel to the posterior plane of the ankle joint. The center position of the rhomboid mechanism remains relatively constant during its extension and retraction. The two horizontal cylindrical connectors 305 of the rhomboid mechanism connect the two ends of the strap, allowing the strap to be worn around the wearer's ankle joint. The two vertical perforated connectors 304 of the rhomboid mechanism connect to the Bowden line 5. Furthermore, it can be understood that the direction of the rhomboid mechanism's assist force is approximately parallel to the lower leg, while the direction of the wrapping force is in the horizontal plane, parallel to the cross-section of the ankle joint.

[0067] See Figure 4 and Figure 5 As shown, Figure 4 As shown. Initially, the angle between the frame of the rhombus mechanism and the horizontal plane is θ0, the center length of the frame is L, the width is d, the distance from the center of the limiting component to the center of the frame is l1, and the radius of the limiting component is r. Then, as... Figure 5 As shown, the angle θ1 between the frame of the rhombic mechanism and the horizontal plane in the final state is:

[0068]

[0069] The maximum contraction length ΔL required for the steel cable and the maximum extension length ΔL of the ankle strap during power assistance a for:

[0070]

[0071] The magnitude of the wrapping force on the ankle joint is:

[0072] F=k△L a

[0073] Here, k represents the stiffness coefficient of the strap. It can be understood that the wrapping force of the strap on the ankle joint depends on multiple factors, including the material properties of the strap, its initial length, and the diameter of the calf it encircles. The above is a simple estimation method, using Hooke's Law to describe the elastic behavior of an elastic material within a small strain range.

[0074] Furthermore, the magnitude of the ankle joint wrapping force can be adjusted by adjusting the center distance l1 from the limiting component to the frame. Adjusting l1 changes the angle θ1 between the diamond-shaped mechanism frame and the horizontal plane at the moment of assistance, thus changing the ankle joint strap stretch length ΔL. a As this changes, the magnitude of the ankle joint's wrapping force F will also change accordingly.

[0075] It should be understood that expressions such as "comprising" and "may include" used in this invention indicate the presence of the disclosed functions, operations, or constituent elements, and do not limit one or more additional functions, operations, and constituent elements. In this invention, terms such as "comprising" and / or "having" are to be interpreted as indicating a particular characteristic, number, operation, constituent element, component, or combination thereof, but not to exclude the possibility of the presence or addition of one or more other characteristics, numbers, operations, constituent elements, components, or combinations thereof.

[0076] Furthermore, in this invention, the expression "and / or" includes any and all combinations of the associated listed words. For example, the expression "A and / or B" can include A, can include B, or can include both A and B.

[0077] In the description of the embodiments of the present invention, it should be noted that, unless otherwise explicitly specified and limited, the term "connection" should be interpreted broadly. For example, "connection" can be a detachable connection or a non-detachable connection; it can be a direct connection or an indirect connection through an intermediate medium. "Fixed connection" refers to a connection where the relative positional relationship remains unchanged after connection. "Rotary connection" refers to a connection where the components can rotate relative to each other after connection. "Sliding connection" refers to a connection where the components can slide relative to each other after connection. The directional terms mentioned in the embodiments of the present invention, such as "top," "bottom," "inner," "outer," "left," and "right," are only for reference to the directions in the accompanying drawings. Therefore, the directional terms used are for better and clearer explanation and understanding of the embodiments of the present invention, and are not intended to indicate or imply that the device or component referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of the present invention.

[0078] Furthermore, in the embodiments of this invention, the mathematical concepts mentioned, such as symmetry, equality, parallelism, and perpendicularity, are all limitations relative to the current technological level, rather than absolute and strict mathematical definitions. Slight deviations are permissible; approximations of symmetry, equality, parallelism, and perpendicularity are all acceptable. For example, "A and B are parallel" means that A and B are parallel or approximately parallel, and the angle between A and B can be between 0 and 10 degrees. "A and B are perpendicular" means that A and B are perpendicular or approximately perpendicular, and the angle between A and B can be between 80 and 100 degrees.

[0079] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. An ankle exoskeleton that assists and enhances joint stability, characterized in that, include: Wearable devices, wearable supports, sliding mechanisms, telescopic components, and transmission cables; The wearable device and wearable support are designed for the wearer to wear outside the ankle joint; The first telescopic end of the telescopic component is fixedly connected to one end of the transmission rope, the second telescopic end is connected to one end of the wearable component, the third telescopic end is passed through by the other end of the transmission rope, and the fourth telescopic end is connected to the other end of the wearable component. The sliding mechanism is connected to the rear side of the wearable bracket, and the other end of the transmission rope passes through the third telescopic end and around the sliding mechanism, and then passes out from the third telescopic end and the first telescopic end in sequence; When the wearable device is worn around the wearer's ankle joint and the wearable bracket is worn at the bottom of the wearer's ankle joint, the other end of the transmission cord is driven by a driving force, which is transmitted to the bottom of the wearer's ankle joint to provide assistance to the wearer's ankle joint. The driving force also causes the first and third telescopic ends of the telescopic component to move closer to each other and the second and fourth telescopic ends to move further apart, so as to cause the wearable device to contract and stretch the ankle joint to provide a wrapping force to the wearer's ankle joint.

2. The exoskeleton according to claim 1, characterized in that, The line segment formed by connecting the second and fourth telescopic ends of the retractable component is parallel to the cross-section of the ankle joint, and the line segment formed by connecting the first and third telescopic ends is perpendicular to the cross-section of the ankle joint.

3. The exoskeleton according to claim 1, characterized in that, The retractable component includes: a limiting component; The limiting component is located on the frame of the retractable component and is used to limit the degree of retractable deformation of the retractable component, so as to limit the length of the wearable component that is shrunk.

4. The exoskeleton according to claim 1, characterized in that, The retractable component includes: four frame strips and four connectors; The first connector connects one end of the first frame to one end of the fourth frame; The second connector connects the other end of the first frame and one end of the second frame; The third connector connects the other end of the second frame to one end of the third frame; The fourth connector connects the other end of the third frame to the other end of the fourth frame; The frame can rotate relative to the connectors it is connected to, and the first to fourth connectors correspond to the first to the fourth telescopic ends, respectively.

5. The exoskeleton according to claim 4, characterized in that, The first to fourth connectors each include: a connecting shaft and a central shaft; The central shaft is fixed to the connecting shaft; The connecting shaft is used to connect the frame, and the frame can rotate relative to the connecting shaft; The central shafts of the first and third connectors are provided with through holes for the transmission rope to pass through; The central axis of the second and fourth connectors is used to connect the two ends of the wearable device.

6. The exoskeleton according to any one of claims 1 to 5, characterized in that, When the length of the retractable component's frame is the same, let the frame length be L, the initial angle between the retractable component's frame and the ankle joint's cross-section be θ0, and the angle between the retractable component's frame and the ankle joint's cross-section when the retractable component is deformed to its maximum extent be θ1. Then: The maximum contraction length ΔL of the transmission rope after being subjected to driving force and the maximum contraction length ΔL of the wearable device a for: △L=4L(sinθ0-sinθ1) △L a =2L(cosθ1-cosθ0)。 7. The exoskeleton according to any one of claims 1 to 5, characterized in that, Also includes: Drive mechanism; The drive mechanism is used to provide driving force to the transmission rope.

8. The exoskeleton according to any one of claims 1 to 5, characterized in that, The sliding mechanism is a pulley.

9. The exoskeleton according to any one of claims 1 to 5, characterized in that, The transmission rope is a steel wire rope.

10. The exoskeleton according to any one of claims 1 to 5, characterized in that, The wearable component is a strap.

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