Six-degree-of-freedom light-weight high-compatibility foot-ankle rehabilitation exoskeleton

Abstract

The application discloses a six-degree-of-freedom light high-compatibility foot-ankle rehabilitation exoskeleton, which comprises an ankle-tibia connecting rod module, an ankle joint shaft module, a forefoot fixing module and a hindfoot fixing module; the ankle-tibia connecting rod module is used for being fixed in parallel with a lower leg and providing a power assisting anchor point at the back side of the lower leg; the forefoot fixing module and the hindfoot fixing module are respectively used for being fixed with the front end and the rear end of the foot of a wearer and providing an end power assisting anchor point at the heel; the ankle joint elastic element is directly contacted with the shoes of a user, and six-degree-of-freedom flexible interaction force is generated. The traditional foot-ankle exoskeleton is limited to toe flexion and dorsiflexion movement, and the elastic element design of the application can adapt to any movement of the foot-ankle within a safety limit, that is, the movement of the foot-ankle, such as internal rotation, external rotation, internal collection, external expansion, toe flexion and dorsiflexion. The application can effectively increase the activity of the foot-ankle, greatly improve the man-machine compatibility, and solve the problem that the existing ankle exoskeleton robot cannot meet the daily functional requirements of patients due to the heavy body configuration and single degree-of-freedom configuration.

Description

Technical Field

[0001] This invention belongs to the fields of exoskeleton technology and medical rehabilitation. Specifically, it is a six-degree-of-freedom lightweight and highly compatible foot and ankle rehabilitation exoskeleton, mainly used for assisting human foot and ankle movement and sports rehabilitation. Background Technology

[0002] The ankle joint, as the joint that shifts the center of gravity during walking, can be effectively assisted to help patients with foot drop reduce calf muscle spasms, thereby achieving a rehabilitation effect. Foot and ankle rehabilitation exoskeletons are designed specifically for the structural characteristics of the ankle joint. Combining human bionics principles with robotics and clinical rehabilitation medicine, they are automated devices that leverage the advantages of robots in performing repetitive and strenuous tasks, enabling precise, automated, and intelligent rehabilitation training, further improving clinical rehabilitation outcomes. In the field of rehabilitation, the specific mechanical structure of foot and ankle exoskeletons, combined with different control methods, allows for the quantification and standardization of rehabilitation training. They can provide active and passive lower limb motor function assistance for patients with lower limb dysfunction, promoting the remodeling of damaged nerve function and enabling quantitative assessment and feedback of the rehabilitation process.

[0003] However, current foot and ankle exoskeletons are mostly designed with rigid, anthropomorphic frames—making it difficult to meet the daily functional needs of wearers, especially the hemiplegic gait unique to patients with foot drop. On the one hand, the limited ankle joint freedom of foot and ankle rehabilitation exoskeletons prevents effective release of foot and ankle movement, increasing walking difficulties and exacerbating the risk of falls. On the other hand, their bulky design makes them extremely inconvenient to wear, slowing down the functional reconstruction of the damaged neuromuscular system and inhibiting patients' enthusiasm for rehabilitation training and their active participation. Therefore, there is an urgent need for a lightweight, highly compatible foot and ankle exoskeleton device that can solve these problems. Summary of the Invention

[0004] To address the aforementioned problems in the existing technology, this application provides a lightweight, highly compatible six-degree-of-freedom foot and ankle rehabilitation exoskeleton that can increase the range of motion of the foot and ankle without affecting the wearer's normal gait function, thus meeting the needs of different groups of people.

[0005] The technical solution of the present invention is as follows:

[0006] A six-degree-of-freedom lightweight and highly compatible foot and ankle rehabilitation exoskeleton includes an ankle-tibialis linkage module 1, an ankle joint axis module 2, a forefoot fixation module 3, and a hindfoot fixation module 4;

[0007] The function of the ankle-shin linkage module 1 is to fix the exoskeleton to the lower leg and provide an anchor point for fixing the flexible transmission rope on the back of the lower leg;

[0008] The ankle-shin linkage module 1 is connected to the ankle joint axis module 2 via a ball bearing, and the two can perform circular motion around the rotation axis of the ball bearing; under the action of the limiting mechanism, the relative rotation angle between the two does not exceed the limit angle of the ankle joint plantar dorsiflexion movement.

[0009] The ankle joint axis module 2 is equipped with a six-degree-of-freedom ankle joint elastic element 202 adapted to the movement of the ankle joint, so that the ankle joint can perform small-range inversion, eversion, adduction, abduction, toe flexion and dorsiflexion movements.

[0010] The function of the forefoot fixing module 3 is to fix the front end of the foot. It is provided with a six-degree-of-freedom toe joint elastic element 304 to adapt to the movement of the toe joint.

[0011] The function of the hindfoot fixation module 4 is to fix the rear end of the foot and provide the end anchor point for the flexible drive rope, which is used to assist the plantar flexion movement of the ankle joint. The compliant control technology based on force feedback is used to assist the ankle joint in plantar flexion movement. That is, when the ankle joint performs plantar flexion movement, it actively provides an appropriate amount of torque and transmits it to the end anchor point of the hindfoot fixation module 4 through the flexible drive rope to provide auxiliary torque to the ankle joint.

[0012] Furthermore, the ankle-shin linkage module 1 includes: two lower leg rods 101, two ankle-shin coupling elements 102, and one lower leg transverse linkage 103;

[0013] The lower leg member 101 is provided with a threaded through hole 1011 at the lower end of the lower leg member and a threaded through hole 1012 in the central area of ​​the lower leg member;

[0014] The ankle-shin coupling element 102 is provided with an upper threaded through hole 1021 and a lower bearing through hole 1022; the upper threaded through hole 1021 of the ankle-shin coupling element is aligned with the lower threaded through hole 1011 of the lower leg member and is fixed by screws.

[0015] The lower leg transverse connecting rod 103 is arc-shaped; a semi-circular through hole 1032 is provided at the center of the arc for fixing the flexible transmission rope; threaded through holes 1031 are provided at the top of the lower leg transverse connecting rod at both ends of the arc; the threaded through holes 1031 at the top of the lower leg transverse connecting rod at both ends of the arc are aligned with the threaded through holes 1012 in the center area of ​​the lower leg rod of the two lower leg members 101, and are fixed by screws, so that the two lower leg members 101 and one lower leg transverse connecting rod 103 are connected into a whole.

[0016] Furthermore, the lower leg member 101 is provided with four straight slots 1013 and two square holes 1014 to reduce the weight of the member;

[0017] The material of the lower leg member 101 is carbon fiber plate.

[0018] Furthermore, the ankle joint axis module 2 includes an ankle joint axis connecting plate 201 and an ankle joint elastic element 202;

[0019] The ankle joint shaft connecting plate 201 has a set of through holes at its upper end, front end and rear end, namely the upper bearing through hole 2011, the front threaded through hole 2012 and the rear pin hole 2013, which are used to connect the ankle-shin linkage module 1, the forefoot fixation module 3 and the hindfoot fixation module 4, respectively.

[0020] There are 3 threaded through holes 2012 at the front end of the ankle joint shaft connecting plate;

[0021] There are two pin holes 2013 at the rear end of the ankle joint axis connecting plate;

[0022] The upper bearing through hole 2011 of the ankle joint shaft connecting plate is connected to the lower bearing through hole 1022 of the ankle-shin coupling element through a ball bearing, so that the two ankle joint shaft modules 2 and the one ankle-shin linkage module 1 are connected into a whole.

[0023] One side of the ankle joint elastic element 202 is fixedly connected to the inner central region of the ankle joint axis connecting plate 201 and is in contact with the ankle joint.

[0024] Furthermore, the ankle joint elastic element 202 includes a plurality of independent elastic struts 2021 arranged in a sagittal plane circumferential array, and the struts are connected by parallel elastic struts 2022.

[0025] Furthermore, the number of the independent elastic support pillars 2021 is 15;

[0026] The independent elastic support 2021 consists of a flexible spherical thin beam joint with the same size at the top and bottom and a flexible column long beam in the middle. Strain gauges are installed at both ends of the column long beam for foot and ankle exoskeleton assist analysis.

[0027] Furthermore, the forefoot fixation module 3 includes two forefoot parallel rods 301, one toe fixation rod 302, one instep fixation rod 303, and one toe joint elastic element 304;

[0028] The forefoot parallel rod 301 has one pin hole at its front end, namely the forefoot parallel rod front pin hole 3012; and three threaded through holes at its rear end, namely the forefoot parallel rod rear threaded through holes 3011; the three forefoot parallel rod rear threaded through holes 3011 are aligned with the three ankle joint axis connecting plates front threaded through holes 2012 and are fixed by screws.

[0029] The toe fixing rod 302 is a straight rod with two pin holes at each end, namely the toe fixing rod pin hole 3021 and the toe fixing rod lower side pin hole 3022.

[0030] The shape of the instep fixing rod 303 is an arc, and there is a pin hole at each end of the arc, namely the pin hole 3031 of the toe fixing rod;

[0031] The toe joint elastic element 304 consists of a flexible spherical thin beam joint with the same size at the top and bottom and a flexible columnar long beam in the middle. Strain gauges are installed at both ends of the columnar long beam for foot and ankle exoskeleton-assisted analysis.

[0032] The pin hole 3031 of the toe fixing rod is aligned with the pin hole 3022 on the lower side of the toe fixing rod and fixed by pins, so that the toe fixing rod 302 and the instep fixing rod 303 together form a ring structure, providing a fixing point for the front of the foot;

[0033] The pin holes 3012 at the front end of the two front foot parallel rods 301 are aligned with the pin holes 3021 at both ends of the toe fixing rod 302, and are fixed by pins, so that the two front foot parallel rods 301 and one toe fixing rod 302 are connected into a whole.

[0034] One side of the toe joint elastic element 304 is fixedly connected to the inner central area of ​​the forefoot parallel rod 301, and the other side is in direct contact with the wearer's toe bone to adapt to the range of motion of the toe joint.

[0035] When worn, the toe joint elastic element 304 is in direct contact with the wearer's toe bone. The six-degree-of-freedom elastic design allows the wearer's toe joint to perform small-range inversion, eversion, adduction, abduction, flexion, and dorsiflexion movements within safe limits, achieving the effect of adapting to the wearer's unrestricted free movement of the foot and ankle.

[0036] Furthermore, the hind foot fixing module 4 includes two hind foot parallel rods 401 and one heel fixing rod 402;

[0037] The rear foot parallel rod 401 has two pin holes at its front end, namely the front pin hole 4011 of the rear foot parallel rod; and two pin holes at its rear end, namely the rear pin hole 4012 of the rear foot parallel rod.

[0038] The front pin hole 4011 of the hind foot parallel rod is connected to the two pin holes 2013 at the rear end of the ankle joint shaft connecting plate 301 by a pin.

[0039] The heel fixing rod 402 has two pin holes at each end, namely heel fixing rod pin holes 4021; and a circular through hole 4022 in the middle, which is the end fixing anchor point of the flexible transmission rope.

[0040] The heel fixing rod pin holes 4021 at both ends of the heel fixing rod 402 are aligned with the rear pin holes 4012 of the rear foot parallel rod, and are fixed by pins, so that the two rear foot parallel rods 401 and one heel fixing rod 402 are connected into a whole.

[0041] Furthermore, the installation method for the flexible rope is as follows:

[0042] The flexible rope passes through the semi-circular through hole 1032 in the middle of the calf transverse connecting rod 103 from top to bottom, and then descends to be fixedly connected to the circular through hole 4022 in the middle of the heel fixing rod 402.

[0043] Furthermore, the wearing method is as follows:

[0044] S1. The ankle joint elastic element 202 is aligned with the rotation axis of the ankle joint, and the lower leg rod 101 is parallel to the lower leg.

[0045] S2. The front end of the foot is fixed in a ring structure formed by the toe fixing rod 302 and the instep fixing rod 303;

[0046] S3. A highly elastic flexible strap passes through the straight groove 1013 and square hole 1014 of the lower leg member 101 to fix the lower leg member 101 to the lower leg.

[0047] The beneficial technical effects of this invention are as follows:

[0048] (1) This invention designs an elastic element capable of realizing six degrees of freedom, enabling the ankle joint to achieve three rotational degrees of freedom and three translational degrees of freedom, thereby improving the comfort and safety of wearable robots and reducing restrictions on the natural movement of the ankle joint. In particular, this effect will be more significant for patients with mild foot drop;

[0049] (2) Without changing the support performance of the ankle-shin linkage module and the forefoot fixation module, the present invention optimizes the redundant parts of the material by using the variable density method with structural weight as the optimization target, and reduces the weight by punching holes, so as to achieve a lightweight configuration design of the foot and ankle exoskeleton design, which can reduce the impact of wearing the foot and ankle exoskeleton on the normal gait of the human body.

[0050] (3) The heel fixing rod and toe fixing rod involved in this invention can adjust the included angle of the fixing rod according to the wearer's foot length to achieve coupling with shoes of different sizes, and have strong applicability and compatibility.

[0051] (4) The six-degree-of-freedom lightweight and highly compatible foot and ankle rehabilitation exoskeleton involved in this invention can provide plantar flexion torque to the wearer as needed by flexible ropes for easy control. The flexible ropes are fixed by anchor points at the heel and the back of the lower leg of the exoskeleton, which conforms to the flexible driving principle of biological structure. Theoretically, this design will maximize energy utilization.

[0052] In summary, the six-degree-of-freedom lightweight and highly compatible foot and ankle rehabilitation exoskeleton disclosed in this invention, without affecting the wearer's normal gait, features a lightweight design and ankle joint degree-of-freedom configuration that fully adapts to and meets the wearer's foot and ankle activities. It has excellent performance characteristics such as comfortable and convenient wear, expanded applicability, and liberation of the foot and ankle to improve human-machine flexibility. Attached Figure Description

[0053] Figure 1 This is a schematic diagram of the overall structure constructed according to a preferred embodiment of the present invention;

[0054] Figure 2 This is an exploded view of the ankle-shin linkage module components constructed according to a preferred embodiment of the present invention;

[0055] Figure 3 This is a schematic diagram of the ankle joint axis module structure constructed according to a preferred embodiment of the present invention;

[0056] Figure 4 This is a schematic diagram of the ankle joint elastic element structure constructed according to a preferred embodiment of the present invention;

[0057] Figure 5 This is a schematic diagram of a six-degree-of-freedom elastic element adapted to ankle joint movement, constructed according to a preferred embodiment of the present invention;

[0058] Figure 6 This is an exploded view of the forefoot fixation module and the adaptive toe joint movable component constructed according to a preferred embodiment of the present invention.

[0059] Figure 7 This is an exploded view of the hind foot fixing module component constructed according to a preferred embodiment of the present invention.

[0060] The correspondence between component names and drawing numbers is as follows: 1-Ankle-Shin Link Module, 101-Lower Leg Member, 1011-Lower Threaded Through Hole at the Lower End of the Lower Leg Member, 1012-Threaded Through Hole in the Central Area of ​​the Lower Leg Member, 1013-Straight Groove, 1014-Square Hole, 102-Ankle-Shin Coupling Element, 1021-Threaded Through Hole at the Upper End of the Ankle-Shin Coupling Element, 1022-Bearing Through Hole at the Lower End of the Ankle-Shin Coupling Element, 103-Lower Leg Lateral Link, 1031-Threaded Through Holes on the Left and Right Sides of the Lower Leg Lateral Link, 1032-Semi-circular Through Hole in the Center of the Lower Leg Lateral Link; 2-Ankle Joint Axis Module, 201-Ankle Joint Axis Connecting Plate, 2011-Bearing Through Hole at the Upper End of the Ankle Joint Axis Connecting Plate, 2012-Threaded Through Hole at the Front End of the Ankle Joint Axis Connecting Plate, 2013-Pin Hole at the Rear End of the Ankle Joint Axis Connecting Plate. 202-Ankle joint elastic element, 2021-Independent elastic support, 2022-Parallel elastic support; 3-Forefoot fixation module, 301-Forefoot parallel rod, 3011-Threaded through hole at the rear end of the forefoot parallel rod, 3012-Pin hole at the front end of the forefoot parallel rod, 302-Toe fixation rod, 3021-Pin hole on the upper side of the toe fixation rod, 3022-Pin hole on the lower side of the toe fixation rod, 303-Dorsal foot fixation rod, 3031-Pin holes at both ends of the dorsal foot fixation rod; 4-Rhindfoot fixation module, 401-Rhindfoot parallel rod, 4011-Pin hole at the front end of the hindfoot parallel rod, 4012-Pin hole at the rear end of the hindfoot parallel rod, 402-Heel fixation rod, 4021-Pin holes on both sides of the heel fixation rod, 4022-Circular through hole in the center of the heel fixation rod. Detailed Implementation

[0061] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be noted that the described embodiments are merely some embodiments of this invention, not all embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention. Obviously, all other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0062] like Figure 1 As shown, the present invention mainly includes the following four modules: ankle-shin linkage module 1, ankle joint axis module 2, forefoot fixation module 3, and hindfoot fixation module 4.

[0063] like Figure 2 As shown, the ankle-shin linkage module 1 includes: two lower leg rods 101, two ankle-shin coupling elements 102, and one lower leg transverse linkage 103. Its function is to fix the exoskeleton to the end of the wearer's limb and provide an anchor point for fixing the Bowden line on the back of the lower leg.

[0064] The lower leg member 101 is provided with a threaded through hole 1011 at the lower end of the lower leg member and a threaded through hole 1012 in the central area of ​​the lower leg member; in order to reduce the overall weight, the lower leg member 101 is made of carbon fiber plate material and is provided with a straight groove 1013 and a square hole 1014.

[0065] The ankle-shin coupling element 102 is provided with an upper threaded through hole 1021 and a lower bearing through hole 1022. The upper threaded through hole 1021 of the ankle-shin coupling element is aligned with the lower threaded through hole 1011 of the calf rod and is fixed by screws.

[0066] The lower leg transverse connecting rod 103 is arc-shaped; a semi-circular through hole 1032 is provided at the center of the arc for fixing the Bowden line; threaded through holes 1031 are provided at the top of the lower leg transverse connecting rod at both ends of the arc; the threaded through holes 1031 at the top of the lower leg transverse connecting rod at both ends of the arc are aligned with the threaded through holes 1012 in the center area of ​​the lower leg rod of the two lower leg members 101, and are fixed by screws, so that the two lower leg members 101 and one lower leg transverse connecting rod 103 are connected into a whole.

[0067] like Figure 3 As shown, the ankle joint axis module 2 includes an ankle joint axis connecting plate 201 and an ankle joint elastic element 202.

[0068] The ankle joint axis connecting plate 201 has a set of through holes at its upper end, front end and rear end, namely the upper bearing through hole 2011, the front threaded through hole 2012, and the rear pin hole 2013, which are used to connect the ankle-shin linkage module 1, the forefoot fixation module 3 and the hindfoot fixation module 4, respectively.

[0069] There are 3 threaded through holes 2012 at the front end of the ankle joint shaft connecting plate, and 2 pin holes 2013 at the rear end of the ankle joint shaft connecting plate.

[0070] The upper bearing through hole 2011 of the ankle joint axis connecting plate is connected to the lower bearing through hole 1022 of the ankle-tibia coupling element through a ball bearing, so that the two ankle joint axis modules 2 and the one ankle-tibia linkage module 1 are connected into a whole, and the ankle joint axis module 2 and the ankle-tibia linkage module 1 can perform circular motion around the rotation axis of the ball bearing; the ankle joint axis connecting plate 201 is provided with a limit mechanism, which restricts the degree of freedom of rotation when the plantar flexion and dorsiflexion angles are too large, and the maximum angle range is less than the plantar dorsiflexion movement limit angle of the human ankle joint, thereby ensuring the safety of the exoskeleton described in this invention.

[0071] One side of the ankle joint elastic element 202 is fixedly connected to the inner central area of ​​the ankle joint axis connecting plate 201 and is in contact with the ankle joint.

[0072] like Figure 4As shown, the ankle joint elastic element 202 consists of 15 independent elastic struts arranged in a sagittal plane circumferential array, with normal elastic struts connecting each strut. When the wearer wears the exoskeleton involved in this invention, the ankle joint elastic element 202 is in direct contact with the wearer's ankle joint. The six-degree-of-freedom elastic design allows the wearer's ankle joint to perform a small range of inversion, eversion, adduction, abduction, toe flexion, and dorsiflexion movements within safe limits, achieving the effect of adapting to the wearer's unrestricted ankle joint movement.

[0073] like Figure 5 As shown, to meet the daily functional requirements of the foot and ankle—pronation (everturing, abduction, dorsiflexion) and supination (inversion, adduction, flexion)—this invention designs a six-degree-of-freedom ankle joint elastic element 202, which consists of several independent elastic struts 2021 arranged in a sagittal plane and parallel elastic struts 2022 between each strut. The six-degree-of-freedom independent elastic struts 2021 can achieve spatial movement in the X, Y, and Z directions and rotation along the corresponding three axes, ensuring that the ankle joint elastic element 202 can liberate the wearer's range of motion, improving the compatibility of different wearers wearing the foot and ankle rehabilitation exoskeleton disclosed in this invention, and enhancing the ergonomic flexibility of the same wearer wearing the foot and ankle rehabilitation exoskeleton disclosed in this invention.

[0074] like Figure 6 As shown, the forefoot fixation module 3 includes two forefoot parallel rods 301, one toe fixation rod 302, one instep fixation rod 303, and one elastic element 304, which are used to fix the front of the foot and adapt to the range of motion of the toe joints.

[0075] The forefoot parallel rod 301 has one pin hole at the front end, namely the forefoot parallel rod front pin hole 3012; and three threaded through holes at the rear end, namely the forefoot parallel rod rear threaded through holes 3011; the three forefoot parallel rod rear threaded through holes 3011 are aligned with the three ankle joint axis connecting plates front threaded through holes 2012 and are fixed by screws.

[0076] The toe-fixing rod 302 is a straight rod with two pin holes at each end: the toe-fixing rod pin hole 3021 and the toe-fixing rod underside pin hole 3022.

[0077] The shape of the instep fixing rod 303 is an arc, and there is a pin hole at each end of the arc, namely the pin hole 3031 of the toe fixing rod.

[0078] The elastic element 304 consists of a flexible spherical thin beam joint with the same size at the top and bottom and a flexible columnar long beam in the middle. Strain gauges are installed at both ends of the columnar long beam for foot and ankle exoskeleton-assisted analysis.

[0079] One side of the elastic element 304 is fixedly connected to the inner central area of ​​the forefoot parallel rod 301, and the other side is in direct contact with the wearer's toe bone to adapt to the range of motion of the toe joint.

[0080] The pin hole 3031 of the toe fixing rod is aligned with the pin hole 3022 on the lower side of the toe fixing rod and fixed by a pin, so that the toe fixing rod 302 and the instep fixing rod 303 together form a ring structure, providing a fixing point for the front of the foot.

[0081] The pin holes 3012 at the front end of the two forefoot parallel rods 301 are aligned with the pin holes 3021 at both ends of the toe fixing rod 302, and fixed by pins, so that the two forefoot parallel rods 301 and one toe fixing rod 302 are connected into a whole, and the toe joint elastic element 304 is fixed on the forefoot parallel rods 301.

[0082] When worn, the elastic element 304 comes into direct contact with the wearer's toe bones. The six-degree-of-freedom elastic design allows the wearer's toe joints to perform small-range inversion, eversion, adduction, abduction, flexion, and dorsiflexion movements within safe limits, achieving the effect of adapting to the wearer's unrestricted free movement of the foot and ankle.

[0083] like Figure 7 As shown, the hind foot fixing module 4 includes two hind foot parallel rods 401 and one heel fixing rod 402, which are used to fix the rear end of the foot and provide the end anchor point for the Bowden line.

[0084] The rear foot parallel member 401 has two pin holes at the front end, namely the front pin hole 4011 of the rear foot parallel member; and two pin holes at the rear end, namely the rear pin hole 4012 of the rear foot parallel member.

[0085] The front pin hole 4011 of the hind foot parallel rod is connected to the two pin holes 2013 at the rear end of the ankle joint axis connecting plate 301 by a pin.

[0086] The heel fixing rod 402 has two pin holes at each end, namely the heel fixing rod pin holes 4021; and a circular through hole 4022 in the middle, which is the end fixing anchor point of the Bowden line.

[0087] The heel fixing rod pin holes 4021 at both ends of the heel fixing rod 402 are aligned with the rear pin holes 4012 of the rear foot parallel rod, and are fixed by pins, so that the two rear foot parallel rods 401 and one heel fixing rod 402 are connected into a whole.

[0088] When the wearer wears the exoskeleton involved in this invention, the robot actively provides the wearer with an auxiliary plantar flexion torque in the sagittal plane, which is provided by Bowden lines. The Bowden lines are installed as follows: from top to bottom, they first pass through the semi-circular through hole 1032 in the middle of the lower leg transverse connecting rod 103, and then go down to be fixedly connected to the circular through hole 4022 in the middle of the heel fixing rod 402.

[0089] The wearing method of the embodiment is as follows:

[0090] S1. The ankle joint elastic element 202 is aligned with the rotation axis of the ankle joint, and the lower leg rod 101 is parallel to the lower leg.

[0091] S2. The front end of the foot is fixed in a ring structure formed by the toe fixing rod 302 and the instep fixing rod 303;

[0092] S3. A highly elastic flexible strap passes through the straight groove 1013 and square hole 1014 of the lower leg member 101 to fix the lower leg member 101 to the lower leg.

[0093] The six-degree-of-freedom lightweight and highly compatible foot and ankle rehabilitation exoskeleton provided by this invention can be selected as a force-interaction-based compliant control technology for easy control. When the wearer's ankle joint undergoes plantar flexion, the robot actively provides a suitable torque and transmits it to the end fixed anchor point through the Bowden line, providing the wearer with an auxiliary plantar flexion torque for the ankle joint, thereby achieving adaptive on-demand assistance.

[0094] The six-degree-of-freedom elastic element constructed in this invention enables pronation and supination of the foot and ankle without affecting the wearer's normal gait, significantly freeing up the ankle's range of motion. This improves the compatibility of the foot and ankle rehabilitation exoskeleton disclosed in this invention with different wearers and enhances the ergonomic flexibility of the same wearer. Furthermore, the topology optimization and weight-reduction design disclosed in this invention significantly reduce the weight of the exoskeleton itself, facilitating wearability during patient rehabilitation training and greatly improving the mobility and comfort of the foot and ankle rehabilitation exoskeleton.

[0095] Although the embodiments of the present invention have been disclosed above, they are not limited to the applications listed in the specification and embodiments. They can be applied to various fields suitable for the present invention. Those skilled in the art will readily understand that the above descriptions are merely preferred embodiments of the present invention and are not intended to limit the invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A six-degree-of-freedom lightweight, highly compatible foot and ankle rehabilitation exoskeleton, characterized in that: It includes an ankle-shin linkage module (1), an ankle joint axis module (2), a forefoot fixation module (3), and a hindfoot fixation module (4); The function of the ankle-shin linkage module (1) is to fix the exoskeleton to the lower leg and provide an anchor point for fixing the flexible transmission rope on the back side of the lower leg; The ankle-shin linkage module (1) is connected to the ankle joint axis module (2) via a ball bearing. The two can make circular motion around the rotation axis of the ball bearing. Under the action of the limiting mechanism, the relative rotation angle between the two does not exceed the limit angle of the ankle joint plantar dorsiflexion movement. The ankle joint axis module (2) is provided with a six-degree-of-freedom ankle joint elastic element (202) adapted to the movement of the ankle joint; the ankle joint elastic element (202) includes several independent elastic pillars (2021) arranged in a circumferential array in the sagittal plane, and the pillars are connected by parallel elastic pillars (2022). The function of the forefoot fixing module (3) is to fix the front end of the foot, and a six-degree-of-freedom toe joint elastic element (304) is provided on it to adapt to the movement of the toe joint; The function of the hindfoot fixation module (4) is to fix the rear end of the foot and provide the end anchor point for the flexible drive rope, which is used to assist the plantar flexion movement of the ankle joint. The compliant control technology based on force feedback is used to assist the ankle joint in plantar flexion movement. That is, when the ankle joint performs plantar flexion movement, it actively provides a suitable torque and transmits it to the end anchor point of the hindfoot fixation module (4) through the flexible drive rope to provide an auxiliary torque to the ankle joint.

2. The six-degree-of-freedom lightweight, highly compatible foot and ankle rehabilitation exoskeleton according to claim 1, characterized in that: The ankle-shin linkage module (1) includes: two lower leg rods (101), two ankle-shin coupling elements (102), and one lower leg transverse linkage (103). The lower leg member (101) is provided with a threaded through hole (1011) at the lower end of the lower leg member and a threaded through hole (1012) in the central area of ​​the lower leg member. The ankle-shin coupling element (102) is provided with an upper threaded through hole (1021) and a lower bearing through hole (1022) of the ankle-shin coupling element; the upper threaded through hole (1021) of the ankle-shin coupling element is aligned with the lower threaded through hole (1011) of the calf rod and is fixed by screws; The lower leg transverse connecting rod (103) is in the shape of an arc; a semi-circular through hole (1032) is provided at the center of the arc for fixing the flexible transmission rope; threaded through holes (1031) are provided at the top of the lower leg transverse connecting rod at both ends of the arc; the threaded through holes (1031) at the top of the lower leg transverse connecting rod at both ends of the arc are aligned with the threaded through holes (1012) in the center area of ​​the lower leg rod of the two lower leg rods (101) respectively, and are fixed by screws, so that the two lower leg rods (101) and the lower leg transverse connecting rod (103) are connected into a whole.

3. The six-degree-of-freedom lightweight, highly compatible foot and ankle rehabilitation exoskeleton according to claim 2, characterized in that: The lower leg member (101) is provided with four straight slots (1013) and two square holes (1014) to reduce the weight of the member; The material of the lower leg member (101) is carbon fiber plate.

4. The six-degree-of-freedom lightweight, highly compatible foot and ankle rehabilitation exoskeleton according to claim 1, characterized in that: The ankle joint axis module (2) includes an ankle joint axis connecting plate (201) and an ankle joint elastic element (202). The ankle joint axis connecting plate (201) has a set of through holes at its upper end, front end and rear end, namely the upper bearing through hole (2011), the front threaded through hole (2012), and the rear pin hole (2013), which are used to connect the ankle-shin linkage module (1), the forefoot fixation module (3) and the hindfoot fixation module (4), respectively. There are a total of 3 threaded through holes (2012) at the front end of the ankle joint shaft connecting plate; There are two pin holes (2013) at the rear end of the ankle joint axis connecting plate; The upper bearing through hole (2011) of the ankle joint shaft connecting plate is connected to the lower bearing through hole (1022) of the ankle-shin coupling element through a ball bearing, so that the two ankle joint shaft modules (2) and the one ankle-shin linkage module (1) are connected into a whole; One side of the ankle joint elastic element (202) is fixedly connected to the inner central region of the ankle joint axis connecting plate (201) and is in contact with the ankle joint.

5. The six-degree-of-freedom lightweight, highly compatible foot and ankle rehabilitation exoskeleton according to claim 1, characterized in that: The number of the independent resilient supports (2021) is 15; The independent elastic support (2021) consists of a flexible spherical thin beam joint with the same size at the top and bottom and a flexible column long beam in the middle. The two ends of the column long beam are equipped with strain gauges for foot and ankle exoskeleton assist analysis.

6. The six-degree-of-freedom lightweight, highly compatible foot and ankle rehabilitation exoskeleton according to claim 1, characterized in that: The forefoot fixation module (3) includes two forefoot parallel rods (301), one toe fixation rod (302), one instep fixation rod (303), and one toe joint elastic element (304). The forefoot parallel rod (301) has one pin hole at its front end, namely the forefoot parallel rod front pin hole (3012); and three threaded through holes at its rear end, namely the forefoot parallel rod rear threaded through holes (3011); the three forefoot parallel rod rear threaded through holes (3011) are aligned with the three ankle joint axis connecting plates front threaded through holes (2012) and are fixed by screws; The toe-fixing rod (302) is a straight rod with two pin holes at each end: a pin hole (3021) on the upper side of the toe-fixing rod and a pin hole (3022) on the lower side of the toe-fixing rod. The shape of the foot instep fixing rod (303) is an arc, and there is a pin hole at each end of the arc, namely the pin holes (3031) at both ends of the foot instep fixing rod. The toe joint elastic element (304) consists of a flexible spherical thin beam joint with the same size at the top and bottom and a flexible columnar long beam in the middle. Strain gauges are installed at both ends of the columnar long beam for foot and ankle exoskeleton assist analysis. The pin holes (3031) at both ends of the foot fixing rod are aligned with the pin holes (3022) on the lower side of the toe fixing rod and fixed by pins, so that the toe fixing rod (302) and the foot fixing rod (303) together form a ring structure, providing a fixing point for the front end of the foot; The pin holes (3012) at the front end of the two forefoot parallel rods (301) are aligned with the pin holes (3021) on the upper side of the toe fixing rods at both ends of the toe fixing rod (302), and are fixed by pins, so that the two forefoot parallel rods (301) and the one toe fixing rod (302) are connected into a whole; The toe joint elastic element (304) is fixedly connected to the inner central area of ​​the forefoot parallel rod (301) on one side, and directly contacts the wearer's toe bone on the other side to adapt to the range of motion of the toe joint. When worn, the toe joint elastic element (304) is in direct contact with the wearer's toe bone. The six-degree-of-freedom elastic design will allow the wearer's toe joint to perform small-range inversion, eversion, adduction, abduction, toe flexion, and dorsiflexion movements within safe limits, achieving the effect of adapting to the wearer's unrestricted free movement of the foot and ankle.

7. The six-degree-of-freedom lightweight, highly compatible foot and ankle rehabilitation exoskeleton according to claim 1, characterized in that: The hind foot fixing module (4) includes two hind foot parallel rods (401) and one heel fixing rod (402). The rear foot parallel rod (401) has two pin holes at its front end, namely the front pin hole (4011) of the rear foot parallel rod; and two pin holes at its rear end, namely the rear pin hole (4012) of the rear foot parallel rod. The front pin hole (4011) of the hind foot parallel rod is connected to the two pin holes (2013) at the rear end of the ankle joint axis connecting plate (301) by means of a pin. The heel fixing rod (402) has two pin holes at each end, namely the heel fixing rod pin holes (4021); and a circular through hole (4022) in the middle, which is the end fixing anchor point of the flexible transmission rope. The heel fixing rod pin holes (4021) at both ends of the heel fixing rod (402) are aligned with the rear pin holes (4012) of the rear foot parallel rod, and are fixed by pins, so that the two rear foot parallel rods (401) and one heel fixing rod (402) are connected into a whole.

8. The six-degree-of-freedom lightweight, highly compatible foot and ankle rehabilitation exoskeleton according to claim 7, characterized in that, The installation method for flexible ropes is as follows: The flexible rope passes through the semi-circular through hole (1032) in the middle of the calf transverse connecting rod (103) from top to bottom, and then goes down to be fixedly connected to the circular through hole (4022) in the middle of the heel fixing rod (402).

9. A six-degree-of-freedom lightweight, highly compatible foot and ankle rehabilitation exoskeleton according to claim 8, characterized in that, The wearing method is as follows: S1, the ankle joint elastic element (202) is aligned with the rotation axis of the ankle joint, and the lower leg rod (101) is parallel to the lower leg; S2, the front end of the foot is fixed in a ring structure formed by the toe fixing rod (302) and the instep fixing rod (303); S3. A highly elastic flexible strap passes through the straight groove (1013) and square hole (1014) of the lower leg member (101) to fix the lower leg member (101) to the lower leg.

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