An exoskeleton bionic ankle system considering the temporal and spatial characteristics of human gait

Abstract

The present application discloses an exoskeleton bionic ankle system that takes into account the temporal and spatial characteristics of human gait, and relates to the technical field of exoskeleton bionic ankle system. The ankle system includes: a bionic arch mechanism, a foot motion mechanism, and a foot recognition mechanism. The bionic arch mechanism is used to support the wearer's foot. The foot motion mechanism includes: an ankle-foot motion module, which is connected to the side of the bionic arch mechanism. The top of the ankle-foot motion module is connected to the exoskeleton lower limb system. The foot recognition mechanism includes at least: a heel recognition module and a toe recognition module distributed at the heel and toe of the bottom of the bionic arch mechanism. The heel recognition module and the toe recognition module are both connected to the bionic arch mechanism through a floating structure to eliminate the tension interference when the foot leaves the ground during walking. The ankle system is more consistent with the gait of the human body during walking and can achieve accurate pressure measurement of the front and back soles of the feet during walking.

Description

Technical Field

[0001] The present application generally relates to the technical field of exoskeleton bionic ankle systems, and specifically to an exoskeleton bionic ankle system that takes into account the temporal and spatial characteristics of human gait. Background Art

[0002] In existing exoskeleton systems, plantar pressure detection modules often use flexible sensors or fixed layout designs. While these sensors can collect pressure data, they generally suffer from short service lives and limited applicability. Furthermore, most detection shoes utilize a closed structure to ensure signal stability, resulting in poor breathability, exacerbating foot sweat accumulation and frictional heat effects, and reducing wearer comfort.

[0003] Traditional rigid sensor detection shoes often embed pressure sensors into the hard insole substrate, resulting in excessive rigidity of the sole contact surface. Long-term use can easily cause arch fatigue and local pressure sores. At the same time, the sensor layout does not match the biomechanical distribution of the human foot and lacks dynamic fitting capabilities. Stress concentration is especially prone to occur in high-pressure areas such as the heel and metatarsal bones, affecting the naturalness of gait. Summary of the Invention

[0004] In view of the above-mentioned defects or deficiencies in the prior art, it is desired to provide an exoskeleton bionic ankle system that takes into account the temporal and spatial characteristics of human gait.

[0005] The present application provides an exoskeleton bionic ankle system that takes into account the temporal and spatial characteristics of human gait. The ankle system is used to connect to the exoskeleton lower limb system to link the wearer's calf and foot. The ankle system includes:

[0006] A bionic arch mechanism, the bionic arch mechanism being used to support the wearer's foot; the bionic arch mechanism having a bionic curved surface for fitting the wearer's foot; the bionic arch mechanism being respectively provided with a foot movement mechanism and a foot recognition mechanism;

[0007] The foot motion mechanism includes: an ankle-foot motion module, which is connected to the side of the bionic arch mechanism; the top of the ankle-foot motion module is connected to the exoskeleton lower limb system; the foot recognition mechanism includes at least: a heel recognition module and a toe recognition module distributed at the heel and toe of the bottom of the bionic arch mechanism, and the heel recognition module and the toe recognition module are both connected to the bionic arch mechanism through a floating structure to eliminate tension interference when the foot leaves the ground during walking.

[0008] According to the technical solution provided in the present application, the bionic arch mechanism includes: an ankle-foot connecting section and a foot connecting section; the ankle-foot motion module is arranged on the side wall of the ankle-foot connecting section, the heel recognition module is arranged at the bottom of the ankle-foot connecting section, and the toe recognition module is connected to the end of the foot connecting section; wherein, a pull ring is provided at the ankle-foot connecting section, and the pull ring is used to thread a strap to fix the wearer's foot; the outer shapes of the ankle-foot connecting section and the foot connecting section are bionic curved surfaces that fit the wearer's foot.

[0009] According to the technical solution provided in the present application, the ankle-foot motion module includes: a calf connecting rod and a connecting structure, one end of the calf connecting rod is used to be connected to the exoskeleton lower limb system, and the other end thereof is connected to the bionic arch mechanism through the connecting structure, and the connecting structure is used to enable the ankle-foot system to simulate the human ankle joint to complete multi-degree-of-freedom movement.

[0010] According to the technical solution provided in this application, the connection structure includes:

[0011] A fisheye bearing, comprising a connecting column section and a bearing section; the connecting column section is threadedly connected to the shank connecting rod, and a through hole is formed in the middle of the bearing section;

[0012] a plug screw having a first optical axis section and a first threaded section, wherein the first optical axis section is connected to the through hole to provide a degree of freedom for the shank connecting rod;

[0013] Ankle-foot connector, the ankle-foot connector is located between the fisheye bearing and the bionic arch mechanism. The first threaded section is threaded with the ankle-foot connector through the through hole, extends from the connecting through hole on the side wall of the ankle-foot connector, and is installed and fixed with the bionic arch mechanism through a locking connection component.

[0014] According to the technical solution provided in this application, the heel recognition module includes:

[0015] a flexible shoe, wherein the heel of the flexible shoe is fixed to the upper surface of the bionic arch mechanism, and the flexible shoe is used to contact the wearer's foot to form foot support;

[0016] a plantar pressure sensor, the plantar pressure sensor being mounted in a first countersunk hole at the bottom of the ankle-foot connection section via a first floating structure;

[0017] The first floating structure comprises:

[0018] A heel sensor mounting box, wherein the heel sensor mounting box is connected to a side of the plantar pressure sensor away from the first countersunk hole, and the heel sensor mounting box is connected to the ankle-foot connecting section via a first positioning screw; the first positioning screw has a second optical axis section and a second threaded section, the second optical axis section is used to be connected to the heel sensor mounting box, and the second threaded section will be connected to the bottom of the ankle-foot connecting section via the heel sensor mounting box, and the heel sensor mounting box can move along the axial direction of the first positioning screw relative to the bionic arch mechanism to eliminate the tension exerted on the heel sensor mounting box during walking.

[0019] According to the technical solution provided in this application, the toe recognition module includes:

[0020] a forefoot connector, the forefoot connector being disposed at the toe portion of the bottom of the flexible shoe, and having an end portion connected to an end portion of the foot connection section; a second countersunk hole being disposed on a side of the forefoot connector away from the flexible shoe, the second countersunk hole being provided with a toe pressure sensor via a second floating structure, the toe pressure sensor being used to collect toe pressure of the wearer;

[0021] The second floating structure comprises:

[0022] A toe sensor mounting box, wherein the toe sensor mounting box is connected to a side of the toe pressure sensor away from the forefoot connecting piece, and the toe sensor mounting box is connected to the forefoot connecting piece via a second positioning screw; the second positioning screw has a third optical axis segment and a third threaded segment, the third optical axis segment is used to be connected to the toe sensor mounting box, and the third threaded segment will be connected to the bottom of the flexible shoe via the toe sensor mounting box, and the toe sensor mounting box can move relative to the flexible shoe along the axial direction of the second positioning screw to eliminate the tension on the toe sensor mounting box during walking.

[0023] According to the technical solution provided in this application, the end of the foot connecting section is provided with two corresponding raised structures, and the raised structures include two semicircular protrusions arranged from top to bottom; the two semicircular protrusions are arranged concentrically, and the radius of the semicircular protrusion located on the upper side is smaller than the radius of the other semicircular protrusion;

[0024] A first mounting hole is provided on the raised structure, and a connecting through hole matching the first mounting hole is provided at the end of the forefoot connecting piece. The first mounting hole and the connecting through hole cooperate with the metatarsophalangeal joint motion module to movably connect the foot connecting section and the forefoot connecting piece. The metatarsophalangeal joint motion module is used to simulate the flexion and extension freedom of the human metatarsophalangeal joint and limit the motion range of the forefoot connecting piece.

[0025] According to the technical solution provided in the present application, a second mounting hole is further provided on the raised structure, the second mounting hole is located below the first mounting hole and is arranged concentrically with the first mounting hole; a limiting protrusion is provided on the end of the forefoot connector for connecting to the raised structure;

[0026] The metatarsophalangeal joint motion module includes:

[0027] A first elastic card and a first pin cooperate with each other, the connecting through hole and the first mounting hole are connected by the first elastic card and the first pin, and the forefoot connector and the bionic arch mechanism can rotate relative to each other along the axis of the first pin, thereby realizing the degree of freedom of the wearer's metatarsophalangeal joint;

[0028] The second pin and the second elastic card cooperate with each other, and the second pin is fixed between the two second mounting holes through the second elastic card. The second pin limits the movement range of the forefoot connector by cooperating with the limiting protrusion.

[0029] According to the technical solution provided in the present application, the bottom of the ankle-foot connection section and the flexible shoe bottom are further provided with a rubber sole and a rubber toe, respectively; and the bottom of the bionic arch mechanism is provided with a gasket.

[0030] To sum up, the present technical solution specifically discloses an exoskeleton bionic ankle system that takes into account the spatiotemporal characteristics of human gait, the system comprising: a bionic arch mechanism, the bionic arch mechanism being used to support the wearer's foot; the bionic arch mechanism having a bionic curved surface for fitting the wearer's foot; a foot movement mechanism and a foot recognition mechanism being respectively arranged on the bionic arch mechanism; the foot movement mechanism comprising: an ankle-foot movement module, the ankle-foot movement module being connected to the side of the bionic arch mechanism; the top of the ankle-foot movement module being connected to an exoskeleton lower limb system; the foot recognition mechanism comprising at least: a heel recognition module and a toe recognition module distributed at the heel and toe of the bottom of the bionic arch mechanism, and the heel recognition module and the toe recognition module being both connected to the bionic arch mechanism through a floating structure to eliminate tension interference when the foot leaves the ground during walking.

[0031] In the existing ankle system, the traditional sensor layout does not match the biomechanical distribution of the human foot, and lacks dynamic fitting capabilities. In particular, stress concentration is easily generated in high-pressure areas such as the heel and metatarsal bones, resulting in low pressure collection accuracy and inability to provide accurate information for judging the wearer's action intentions. This application sets up an ankle-foot motion module to achieve a compound motion of ankle pitch and rotation, thereby fitting the human walking posture; by setting up a heel recognition module and a toe recognition module with a floating structure, the lateral tension interference when the heel or toe leaves the ground can be eliminated. At the same time, the toe recognition module uses an elastic rubber toe and a floating structure to synchronously capture the impact force of touching the ground. The heel recognition module and the toe recognition module jointly achieve high-precision recognition of gait phases. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Other features, objects and advantages of the present application will become more apparent upon reading the detailed description of non-limiting embodiments made with reference to the following drawings:

[0033] Figure 1 This is a schematic diagram of the structure of an exoskeleton bionic ankle system that takes into account the temporal and spatial characteristics of human gait;

[0034] Figure 2 This is a structural diagram of the ankle-foot motion module;

[0035] Figure 3 This is a structural diagram of the heel recognition module;

[0036] Figure 4 This is a structural diagram of the toe recognition module;

[0037] Figure 5 Schematic diagram of the structure of the metatarsophalangeal joint motion module;

[0038] Figure 6 Schematic diagram of the structure of the bionic arch mechanism.

[0039] Numbers in the figure: 1, ankle-foot motion module; 2, heel recognition module; 3, toe recognition module; 4, metatarsophalangeal joint motion module; 101, calf connecting rod; 102, plug screw; 103, first anti-slip gasket; 104, fisheye bearing; 1041, connecting column section; 1042, bearing section; 105, ankle-foot connecting piece; 106, second anti-slip gasket; 108, first pair of top nuts; 109, second pair of top nuts; 201, heel fixing plate; 202, flexible shoe; 203, plantar pressure sensor; 204, third pair of top nuts; 205, heel sensor mounting box; 206, first positioning screw; 207, rubber shoe Outer sole; 301, toe fixing plate; 302, forefoot connecting piece; 3021, second countersunk hole; 3022, connecting hole; 3023, limiting protrusion; 303, toe sensor mounting box; 304, rubber toe; 305, toe pressure sensor; 401, first pin; 402, gasket; 403, second elastic card; 404, first elastic card; 405, second pin; 5, bionic arch mechanism; 51, ankle-foot connecting section; 510, connecting through hole; 511, first countersunk hole; 52, foot connecting section; 501, pull ring; 521, protrusion structure; 5211, first mounting hole; 5212, second mounting hole. DETAILED DESCRIPTION

[0040] The present application will be further described in detail below with reference to the accompanying drawings and examples. It should be understood that the specific embodiments described herein are merely for the purpose of explaining the relevant invention and are not intended to limit the invention. It should also be noted that, for ease of description, only portions relevant to the invention are shown in the accompanying drawings.

[0041] It should be noted that, in the absence of conflict, the embodiments and features of the embodiments in this application can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0042] Example 1

[0043] In order to make the technical solutions of the embodiments of the present application clearer and easier to understand, the application background of the embodiments of the present application is introduced below.

[0044] In modern exoskeleton systems, the plantar pressure detection module serves as the core sensing unit for human-machine interaction. Its performance directly determines the system's accuracy in capturing human movement intentions and the efficiency of its control response. Whether assisting patients in regaining walking function in medical rehabilitation or enhancing the wearer's load-bearing capacity in industrial and military scenarios, accurately acquiring plantar pressure distribution data is a key prerequisite for achieving adaptive exoskeleton assistance and preventing sports injuries.

[0045] However, current plantar pressure detection technology in exoskeleton systems still faces many challenges. Existing plantar pressure detection modules mostly use flexible sensors or fixed layout designs. Although they can achieve basic pressure data collection, they generally have a short service life. Flexible sensors are limited by material properties and are prone to structural fatigue and signal attenuation during repeated bending and squeezing, making it difficult to meet the needs of long-term wear and use of exoskeletons. Fixed layout designs lack adaptability to individual foot morphology differences and changes in movement status, resulting in serious limitations in applicable scenarios. At the same time, to ensure the stability of signal transmission, most detection shoes use a closed structure, which greatly weakens the breathability of the shoes. During long-term wear, the closed structure exacerbates the accumulation of sweat on the feet and the frictional heat effect.

[0046] Traditional rigid sensor detection shoes also have significant defects. Such detection shoes usually embed pressure sensors into the hard insole substrate, which makes the sole contact surface too rigid and destroys the natural mechanical buffering mechanism of the human foot. During long-term use, the wearer is very likely to suffer from arch fatigue and even local pressure sores. More importantly, the existing sensor layout fails to fully consider the biomechanical distribution characteristics of the human foot and lacks dynamic fitting capabilities. During human walking, running and other movements, severe stress concentration will occur in high-pressure areas such as the heel and metatarsal bones, which not only affects the naturalness of the wearer's gait, but may also cause irreversible damage to the bones and joints of the foot, limiting the promotion and development of exoskeleton systems in practical applications.

[0047] In view of this, please refer to Figure 1 The embodiment shown is a schematic diagram of the structure of an exoskeleton bionic ankle system that takes into account the temporal and spatial characteristics of human gait. This exoskeleton bionic ankle system is more closely aligned with the human gait during walking, and can accurately measure the pressure on the forefoot and rearfoot of the wearer during walking. It can then determine the wearer's intention to walk, stand, go up and down hills, and other movements in real time, thereby dynamically adjusting the power direction and strength to achieve "human-machine integration" collaborative movement. Specifically, the exoskeleton bionic ankle system includes:

[0048] The bionic arch mechanism 5 is used to support the wearer's foot; the bionic arch mechanism 5 has a bionic curved surface for fitting the wearer's foot; the bionic arch mechanism 5 is respectively provided with a foot movement mechanism and a foot recognition mechanism;

[0049] The foot motion mechanism includes: an ankle-foot motion module 1, which is connected to the side of the bionic arch mechanism 5; the top of the ankle-foot motion module 1 is connected to the exoskeleton lower limb system; the foot recognition mechanism includes at least: a heel recognition module 2 and a toe recognition module 3 distributed at the heel and toe of the bottom of the bionic arch mechanism 5, and the heel recognition module 2 and the toe recognition module 3 are both connected to the bionic arch mechanism 5 through a floating structure to eliminate the tension interference when the foot leaves the ground during walking.

[0050] Specifically, the bionic arch mechanism 5 is used to support the wearer's foot and is mainly worn on the wearer's ankle and heel. At the same time, the bionic arch mechanism 5 is designed to obtain a bionic surface based on the biomechanical curve of the human plantar, which can effectively adapt to the deformation of the arch during the gait cycle, achieve the effect of dynamic fitting of the arch and center of gravity transfer, and ensure the smoothness of the gait; in addition, the bionic arch mechanism is also provided with a foot movement mechanism and a foot recognition mechanism. The foot movement mechanism is used to simulate the multi-degree-of-freedom movement of the human foot joints, and the foot recognition mechanism is used to collect the pressure distribution of the heel area and the toe area during the wearer's walking.

[0051] Furthermore, the foot motion mechanism includes: an ankle-foot motion module 1; as the name suggests, the ankle-foot motion module 1 is installed at the ankle of the wearer, and it is also used to connect the calf section of the exoskeleton lower limb system, so that the human foot and lower limb system can be linked and controlled; the foot recognition mechanism includes at least: a heel recognition module 2 and a toe recognition module 3, both of which are connected to the bionic arch mechanism 5 through corresponding floating structures, so that it can float and cooperate with the bionic arch mechanism 5, avoiding the situation where the wearer's heel leaves the ground while walking due to excessive lateral tension interference under traditional rigid connection, and can effectively improve the pressure detection accuracy, so that the entire foot recognition mechanism can realize the function of gait phase recognition under the joint control of the toe and heel recognition modules, thereby dynamically adjusting the power assistance direction and strength to achieve "human-machine integration" collaborative movement.

[0052] In a preferred embodiment, the bionic arch mechanism 5 includes: an ankle-foot connecting section 51 and a foot connecting section 52; the ankle-foot motion module 1 is arranged on the side wall of the ankle-foot connecting section 51, the heel recognition module 2 is arranged at the bottom of the ankle-foot connecting section 51, and the toe recognition module 3 is connected to the end of the foot connecting section 52; wherein, a pull ring 501 is provided at the ankle-foot connecting section 51, and the pull ring 501 is used to thread a strap to fix the wearer's foot; the outer shapes of the ankle-foot connecting section 51 and the foot connecting section 52 are bionic curves that fit the wearer's foot.

[0053] Specifically, the bionic arch mechanism 5 includes an ankle-foot connecting section 51 and a foot connecting section 52. The ankle-foot connecting section 51 and the foot connecting section 52 present the arch shape of the human body from the metatarsophalangeal joint to one end of the heel. The entire bionic arch mechanism 5 is also designed with a curved support structure with better fit according to the human body structure, so that it can better fit the gait of the human body during walking; the ankle-foot motion module 1, the heel recognition module 2 and the toe recognition module 3 are arranged at the corresponding positions of the bionic arch mechanism 5 according to the human body structure; because the exoskeleton bionic ankle system also needs to be fixed to the wearer, multiple pull rings 501 are provided at the ankle-foot connecting section 51, and the pull ring 501 can be a polyetheretherketone pull ring, and is connected to the bionic arch mechanism 5 by rivets; in actual use, the pull ring 501 fixes the wearer's feet by inserting Velcro straps therein.

[0054] In a preferred embodiment, see Figure 2 The ankle-foot motion module 1 includes: a calf connecting rod 101 and a connecting structure. One end of the calf connecting rod 101 is used to connect to the exoskeleton lower limb system, and the other end is connected to the bionic arch mechanism 5 through the connecting structure. The connecting structure is used to enable the ankle-foot system to simulate the human ankle joint to complete multi-degree-of-freedom movement.

[0055] In order to ensure the freedom of the human ankle joint during actual walking, the calf connecting rod 101 in the ankle-foot motion module 1 is rigidly connected to the bionic arch mechanism 5 through a designed connection structure. At the same time, the calf connecting rod 101 itself is movably connected to the connection structure (the movably connected here means that the calf connecting rod 101 can move in a small range). Therefore, the calf connecting rod 101 not only forms the force transmission starting point of the main support frame of the sole of the foot, but also realizes multi-degree-of-freedom rotation of the ankle joint in the sagittal plane and the coronal plane, ensuring the fit of the wearer's foot movement.

[0056] Furthermore, the aforementioned connection structure includes: a fisheye bearing 104, the fisheye bearing 104 having a connecting column section 1041 and a bearing section 1042; the connecting column section 1041 is threadedly connected to the calf connecting rod 101, and a through hole is opened in the middle of the bearing section 1042;

[0057] The plug screw 102 has a first optical axis section and a first threaded section, and the first optical axis section is connected to the through hole to provide a degree of freedom for the calf connecting rod 101;

[0058] The ankle-foot connector 105 is located between the fisheye bearing 104 and the bionic arch mechanism 5. After the first threaded section is threadedly connected to the ankle-foot connector 105 through the through hole, it extends from the connecting through hole 510 on the side wall of the ankle-foot connector section 51 and is installed and fixed to the bionic arch mechanism 5 through a locking connection assembly.

[0059] Specifically, the connection structure includes: a fisheye bearing 104, a plug screw 102, an ankle-foot connector 105, a first top nut 108, a first anti-slip gasket 103, a second anti-slip gasket 106, and a second top nut 109. The end of the calf connecting rod 101 is provided with an internal threaded hole, the connecting column section 1041 of the fisheye bearing 104 is an external threaded rod, and the second top nut 109 is installed on the connecting column section 1041 of the fisheye bearing 104. The fisheye bearing 104 is then connected to the calf connecting rod 101 with a screw thread. After the threaded connection, the second top nut 109 is rotated to tighten the end face of the calf connecting rod 101 to achieve thread pre-tightening; the plug screw 102 includes two stepped connecting sections, one connecting section is the first optical axis section, and the other connecting section is the first threaded section; wherein, the first optical axis section is closer to the outside of the ankle system relative to the first threaded section, and the aforementioned locking connection components are the "first top nut 108, the first anti-slip gasket 103, the second anti-slip gasket 106, the second top nut 109" and other connecting parts.

[0060] During the process of connecting the driving screw 102 with various components, the driving screw 102 needs to pass through the first anti-slip pad 103, the inner ring of the bearing section 1042, the second anti-slip pad 106, and the ankle-foot connector 105 in sequence, and then be connected to the ankle-foot connector 51 of the bionic arch mechanism 5. After the connection, the first optical axis section corresponds to the first anti-slip pad 103 and the bearing section 1042, while the first threaded section is threadedly connected to the ankle-foot connector 105, the second anti-slip pad 106, and the connecting through hole 510, and finally fixed to the bionic arch mechanism 5 by screwing the second top nut 109 with the first threaded section. Based on the above connection description, it can be seen that the calf connecting rod 101 and the fisheye bearing 104 are connected at the first optical axis section to achieve the combined movement of ankle pitch and rotation, ensuring the fit between the person and the equipment at the ankle joint.

[0061] In a preferred embodiment, see Figure 3 , the heel recognition module 2 includes:

[0062] A flexible shoe 202, wherein the heel portion of the flexible shoe 202 is fixed to the upper surface of the bionic arch mechanism 5, and the flexible shoe 202 is used to contact the wearer's foot to form foot support;

[0063] The plantar pressure sensor 203 is installed in the first countersunk hole 511 at the bottom of the ankle-foot connecting section 51 through a first floating structure;

[0064] The first floating structure includes: a heel sensor mounting box 205, which is connected to the side of the plantar pressure sensor 203 away from the first countersunk hole 511, and the heel sensor mounting box 205 is connected to the ankle-foot connecting section 51 through a first positioning screw 206; the first positioning screw 206 has a first optical axis section and a first threaded section, the first optical axis section is used to connect to the heel sensor mounting box 205, and the first threaded section will be connected to the bottom of the ankle-foot connecting section 51 via the heel sensor mounting box 205, and the heel sensor mounting box 205 can move along the axial direction of the first positioning screw 206 relative to the bionic arch mechanism 5 to eliminate the tension on the heel sensor mounting box 205 during walking.

[0065] Specifically, the heel recognition module 2 includes: a flexible shoe 202, a plantar pressure sensor 203 and a first floating structure. The flexible shoe 202 can provide wearing comfort for the ankle system. The plantar pressure sensor 203 is used to collect pressure values ​​in the heel area. The first floating structure ensures that the plantar pressure sensor 203 is not directly fixed to the bionic arch mechanism 5. When the friction between the sole and the ground and the inertia of the foot movement generate lateral tension, the tension can be converted into axial displacement rather than directly pulling the plantar pressure sensor 203, thereby avoiding the lateral tension directly acting on the sensor, which can effectively eliminate interference and improve the pressure detection accuracy.

[0066] Furthermore, the first floating structure includes: a heel sensor mounting box 205, a first positioning screw 206, a heel fixing plate 201 and a third top nut 204; during the connection process, corresponding through holes are provided on the heel of the flexible shoe 202 and the heel fixing plate 201, and corresponding threaded holes are provided on the bionic arch mechanism 5, and the two can be fixed by a connecting member (for example, a bolt); a first countersunk hole 511 is provided at the bottom of the bionic arch mechanism 5 as the mounting end surface of the plantar pressure sensor 203, and the other side of the plantar pressure sensor 203 is connected to the heel sensor mounting box 205 The heel sensor mounting box 205 is provided with a flange, and the second optical axis segment of the first positioning screw 206 will pass through the flange hole on the flange of the heel sensor mounting box 205, so that the heel sensor mounting box 205 can move freely along the axial direction of the first positioning screw 206, and the second threaded shaft segment will be screwed into the bottom of the bionic arch mechanism 5 for relative fixation. In this way, the heel sensor mounting box 205 and the plantar pressure sensor 203 connected thereto can move in a small range along the axial direction of the first positioning screw 206 relative to the bionic arch mechanism 5, thereby effectively eliminating interference and improving the pressure detection accuracy.

[0067] In a preferred embodiment, see Figure 4 , the toe recognition module 3 includes:

[0068] A forefoot connector 302 is provided at the toe portion of the bottom of the flexible shoe 202, and its end is also connected to the end of the foot connection section 52. A second countersunk hole 3021 is provided on the side of the forefoot connector 302 away from the flexible shoe 202. A toe pressure sensor 305 is provided in the second countersunk hole 3021 via a second floating structure. The toe pressure sensor 305 is used to collect pressure at the toe portion of the wearer's toes.

[0069] The second floating structure includes: a toe sensor mounting box 303, which is connected to the toe pressure sensor 305 on the side away from the forefoot connector 302, and the toe sensor mounting box 303 is connected to the forefoot connector 302 through a second positioning screw; the second positioning screw has a third optical axis segment and a third thread segment, the third optical axis segment is used to be connected to the toe sensor mounting box 303, and the third thread segment will be connected to the bottom of the flexible shoe 202 via the toe sensor mounting box 303, and the toe sensor mounting box 303 can move along the axis direction of the second positioning screw relative to the flexible shoe 202 to eliminate the tension on the toe sensor mounting box 303 during walking.

[0070] The toe recognition module 3 is similar to the aforementioned heel recognition module 2 and is provided with a second floating structure to eliminate the tension on the toe, thereby improving the pressure recognition accuracy of the toe recognition module 3; in addition, the toe recognition module 3 includes a forefoot connector 302, the end of which can be connected to the end of the bionic arch mechanism 5, which is equivalent to being connected to the metatarsophalangeal joint of the human body, and the top end face of the forefoot connector 302 is connected to the toe part of the bottom of the flexible shoe 202. It can be understood that the entire forefoot connector 302 serves as a supporting component for the forefoot of the wearer's foot; the toe pressure sensor 305 here is used to collect pressure values ​​in the toe area.

[0071] Furthermore, the second floating structure includes: a toe fixing plate 301, a forefoot connector 302 and a toe sensor mounting box 303 which are also fixed by connectors. The second countersunk hole 3021 at the bottom of the forefoot connector 302 forms the mounting end face of the toe pressure sensor 305. The third optical axis segment of the second positioning screw passes through the flange hole of the toe sensor mounting box 303 and is threadedly connected to the forefoot connector 302 using its third threaded segment. At this time, the toe sensor mounting box 303 and the toe pressure sensor 305 connected thereto can move in a small range along the axial direction of the second positioning screw relative to the bionic arch mechanism 5, thereby effectively eliminating interference and improving the pressure detection accuracy.

[0072] In a preferred embodiment, see Figure 4 、 Figure 5 and Figure 6 The end of the foot connecting section 52 is provided with two corresponding protrusion structures 521, and the protrusion structure 521 includes two semicircular protrusions arranged from top to bottom; the two semicircular protrusions are arranged concentrically, and the radius of the semicircular protrusion located on the upper side is smaller than the radius of the other semicircular protrusion;

[0073] A first mounting hole 5211 is provided on the raised structure 521, and a connecting hole 3022 matching the first mounting hole 5211 is provided at the end of the forefoot connecting piece 302. The first mounting hole 5211 and the connecting hole 3022 cooperate with the metatarsophalangeal joint motion module 4 to movably connect the foot connecting section 52 and the forefoot connecting piece 302. The metatarsophalangeal joint motion module 4 is used to simulate the flexion and extension freedom of the metatarsophalangeal joint of the human body and limit the range of motion of the forefoot connecting piece 302.

[0074] Specifically, the connection between the forefoot connector 302 and the bionic arch mechanism 5 is located at the metatarsophalangeal joint of the human body, which also requires a certain degree of freedom of joint flexion and extension. Therefore, the forefoot connector 302 and the bionic arch mechanism 5 are connected through the metatarsophalangeal joint motion module 4. Among them, the end of the foot connection section 52 is provided with two corresponding protrusions 521. The protrusions 521 are the core structure connected to the end of the forefoot connector 302. The bottom of the protrusions 521 is semicircular and can act as a semicircular roller, thereby making the process of transferring the center of gravity from the rear to the forefoot smoother during the wearer's actual walking process and making human-computer interaction more flexible. Under the connection of the metatarsophalangeal joint motion module 4, the forefoot connector 302 and the bionic arch mechanism 5 are not directly fixed, but have a certain range of motion, allowing the forefoot connector 302 to flex relative to the arch of the foot. At the same time, the metatarsophalangeal joint motion module 4 can also achieve hard motion limit through mechanical interference through a limit design to avoid joint overload.

[0075] Specifically, the raised structure 521 further defines a second mounting hole 5212, which is located below the first mounting hole 5211 and concentric with the first mounting hole 5211. A limiting protrusion 3023 is provided at the end of the forefoot connector 302 for connection with the raised structure 521.

[0076] The metatarsophalangeal joint motion module 4 includes a first elastic card 404 and a first pin 401 that cooperate with each other. The connecting hole 3022 and the first mounting hole 5211 are connected via the first elastic card 404 and the first pin 401. The forefoot connector 302 and the bionic arch mechanism 5 can rotate relative to each other along the axis of the first pin 401, thereby achieving the wearer's metatarsophalangeal joint's freedom of movement.

[0077] The second pin 405 and the second elastic card 403 cooperate with each other, and the second pin 405 is fixed between the two second mounting holes 5212 through the second elastic card 403. The second pin 405 limits the movement range of the forefoot connector 302 by cooperating with the limiting protrusion 3023.

[0078] Specifically, the metatarsophalangeal joint motion module 4 includes: a first pin 401, a first elastic card 404, a second elastic card 403 and a second pin 405. The first pin 401 passes through the first mounting hole 5211 and the connecting hole 3022 in sequence, and then its end is fixed with the first elastic card 404. At this time, the first pin 401 forms a clearance fit with the forefoot connector 302 and the bionic arch mechanism 5. The forefoot connector 302 and the bionic arch mechanism 5 can rotate relative to each other along the first pin 401, thereby realizing the freedom of the wearer's metatarsophalangeal joint and improving the fit of the plantar structure.

[0079] In addition, a second mounting hole 5212 with a slightly smaller aperture is provided below the first mounting hole 5211 of the bionic arch mechanism 5, and the two are coaxially arranged to ensure coordination. After the second pin shaft 405 passes through the second mounting hole 5212 on the two protruding structures 521, its end is fixed with a second elastic card 403; in the embodiment of the present application, a limiting protrusion 3023 is provided at the connection between the forefoot connector 302 and the bionic arch mechanism 5, and the limiting protrusion 3023 is provided adjacent to the second pin shaft 405, and when the forefoot connector 302 moves to the extreme position, the limiting protrusion 3023 will be locked against the second pin shaft 405 to achieve limitation within the corresponding angle range, thereby preventing the forefoot connector 302 from moving beyond the limit.

[0080] In a preferred embodiment, the bottom of the ankle-foot connection section 51 and the bottom of the flexible shoe 202 are further provided with a rubber sole 207 and a rubber toe 304 respectively; and the bottom of the bionic arch mechanism 5 is provided with a gasket 402 .

[0081] Specifically, the rubber sole 207 and the rubber toe 304 can be connected to the installation holes reserved on the outside of the heel sensor mounting box 205 and the toe sensor mounting box 303 respectively through connecting parts. The rubber sole 207 and the rubber toe 304 can not only improve the wearing comfort but also absorb some tension energy when lateral tension is generated, thereby improving the recognition accuracy of the sensor. The gasket 402 at the bottom of the bionic arch mechanism 5 can be made of polyurethane gasket, which can play a role in buffering and reducing friction.

[0082] Based on the above description, the working principle of the exoskeleton bionic ankle system provided by this application that takes into account the temporal and spatial characteristics of human gait is as follows:

[0083] Connect the calf connecting rod 101 of the ankle-foot motion module 1 to the exoskeleton lower limb system. Tighten the second top nut 109 on the fisheye bearing 104 and preload to a moderate resistance. The wearer places their foot into the flexible shoe 202 and adjusts the rubber sole 207 and rubber toe 304 of the heel and toe recognition module so that the center of the heel aligns with the corresponding heel sensor mounting box 205 and toe sensor mounting box 303 (aligning the forefoot metatarsal area with the toe sensors). Then, insert and tighten the Velcro straps inside the pull rings on both sides of the heel, ensuring that the foot does not slip and there is no localized strong pressure. Once the wearer is wearing the shoe, they can walk normally. As the wearer walks, the toe pressure sensor 305 reflects the pressure changes in the metatarsophalangeal joint and toe area in real time. Simultaneously, the plantar pressure sensor 203 collects the pressure distribution at the heel. By analyzing the pressure changes between the forefoot and the forefoot, different gait phases can be distinguished, thus providing judgment criteria for switching the exoskeleton's power-assistance mode.

[0084] In addition, the structural advantages of this application are as follows:

[0085] (1) Description of structure:

[0086] The ankle-foot motion module 1 is used to connect the exoskeleton calf segment and simulate the multi-degree-of-freedom motion of the human ankle joint. Through the synergistic effect of the connection structure, it realizes the compound motion of the ankle pitch and rotation, ensuring the fit between the person and the device at the ankle joint.

[0087] The heel recognition module 2 is connected to the bionic arch mechanism 5 via a first floating structure to collect pressure distribution in the heel area. It includes an array of plantar pressure sensors 203 embedded in a flexible shoe 202. A first positioning screw 206 within the first floating structure and an auxiliary elastic gasket achieve floating coordination, eliminating lateral tension interference when the heel leaves the ground during walking and improving pressure detection accuracy.

[0088] In addition to the design of the second floating structure of the toe recognition module 3, it is integrated in the forefoot area. Because it includes a forefoot connector 302 and a rubber toe 304 component, it adapts to gait contact cushioning and combines with the heel recognition module 2 to realize the function of gait phase recognition.

[0089] The metatarsophalangeal joint motion module 4 simulates the flexion and extension degrees of freedom of the human metatarsophalangeal joint and limits its range of motion. It uses a dual-pin hinge limiter structure to allow the forefoot to flex relative to the arch of the foot. Mechanical interference between the boss and the pin provides a hard limit at the extreme position to prevent joint overload.

[0090] The bionic arch mechanism 5 achieves dynamic fit and center of gravity transfer of the arch through bionic curved surface support and a roller guide structure of the raised structure 521; the bionic arch mechanism 5 comprises polyetheretherketone material and is designed according to the biomechanical curve of the human plantar, adapting to the deformation of the arch during the gait cycle. The raised structure 521 is embedded in the end of the arch to reduce the friction resistance of the center of gravity transfer from the heel to the forefoot, thereby improving the smoothness of the gait.

[0091] (2) Description of the effects of structural design:

[0092] The exoskeleton calf connecting rod 101 is rigidly connected to the bionic arch mechanism 5 via the flange structure of the ankle-foot motion module 1, forming the force transmission starting point of the main plantar support frame. This enables the ankle joint to rotate in multiple degrees of freedom in the sagittal and coronal planes, ensuring a consistent fit for the wearer's foot movements. The front end of the bionic arch mechanism 5 is flexibly connected to the metatarsophalangeal joint motion mechanism, while the rear end is flexibly connected to the heel recognition module 2 via an axial floating structure. Its curved support layer is designed based on the biomechanical curve of the human arch. Combined with the semicircular roller guidance of the terminal protrusion structure 521, it adapts to arch deformation during the gait cycle and reduces frictional resistance to weight transfer, achieving dynamic load distribution of plantar pressure.

[0093] The heel recognition module 2 and the toe recognition module 3 are respectively integrated into the rear end of the bionic arch mechanism 5 and the front end of the metatarsophalangeal joint motion module 4. The heel recognition module 2 eliminates lateral tension interference through the axial floating design of the first positioning screw 206, and the toe recognition module 3 uses the elastic rubber toe 304 and the floating structure to synchronously capture the impact force of touching the ground. The two are combined to achieve high-precision recognition of gait phase. The metatarsophalangeal joint motion module 4 balances load transfer and freedom of movement through a double-pin hinge and mechanical limit design, allowing the forefoot to flex relative to the arch of the foot, and performs limit interference at the extreme position to prevent joint overload and ensure wearing safety. In addition, the flexible shoe 202 serves as a packaging carrier for human-computer interaction, integrating various mechanical modules and detection components together, combining the wearing comfort and force transmission of ordinary shoes, and achieving pressure detection accuracy and reliability.

[0094] The above description is merely a preferred embodiment of the present application and an illustration of the technical principles employed. Those skilled in the art should understand that the scope of the invention herein is not limited to the technical solutions formed by the specific combination of the above-mentioned technical features, but also encompasses other technical solutions formed by any combination of the above-mentioned technical features or their equivalents without departing from the inventive concept. For example, a technical solution formed by replacing the above-mentioned features with (but not limited to) technical features having similar functions disclosed in this application.

Claims

1. An exoskeleton bionic ankle system that takes into account the temporal and spatial characteristics of human gait, characterized in that: The ankle system is used to connect to the exoskeleton lower limb system to link the wearer's calf and foot. The ankle system includes: A bionic arch mechanism (5), the bionic arch mechanism (5) being used to support a wearer's foot; the bionic arch mechanism (5) having a bionic curved surface for fitting the wearer's foot; and a foot movement mechanism and a foot recognition mechanism being respectively provided on the bionic arch mechanism (5); The foot motion mechanism comprises: an ankle-foot motion module (1), the ankle-foot motion module (1) being connected to the side of the bionic arch mechanism (5); the top of the ankle-foot motion module (1) being connected to the exoskeleton lower limb system; the foot recognition mechanism at least comprises: a heel recognition module (2) and a toe recognition module (3) distributed at the heel and toe of the bottom of the bionic arch mechanism (5), and the heel recognition module (2) and the toe recognition module (3) are both connected to the bionic arch mechanism (5) via a floating structure to eliminate tension interference when the foot leaves the ground during walking; The bionic arch mechanism (5) comprises: an ankle-foot connecting section (51) and a foot connecting section (52); the ankle-foot motion module (1) is arranged on the side wall of the ankle-foot connecting section (51), the heel recognition module (2) is arranged on the bottom of the ankle-foot connecting section (51), and the toe recognition module (3) is connected to the end of the foot connecting section (52); wherein, a pull ring (501) is provided at the ankle-foot connecting section (51), and the pull ring (501) is used to pass a strap to fix the wearer's foot; the outer shapes of the ankle-foot connecting section (51) and the foot connecting section (52) are bionic curved surfaces that fit the wearer's foot; The ankle-foot motion module (1) comprises: a calf connecting rod (101) and a connecting structure, wherein one end of the calf connecting rod (101) is used to be connected to the exoskeleton lower limb system, and the other end thereof is connected to the bionic arch mechanism (5) via the connecting structure, and the connecting structure is used to enable the ankle-foot system to simulate the human ankle joint to complete multi-degree-of-freedom motion; The connection structure includes: A fisheye bearing (104), the fisheye bearing (104) comprising a connecting column section (1041) and a bearing section (1042); the connecting column section (1041) is threadedly connected to the shank connecting rod (101), and a through hole is formed in the middle of the bearing section (1042); a driving screw (102), the driving screw (102) having a first optical axis section and a first threaded section, the first optical axis section being connected to the through hole to provide a degree of freedom for the calf connecting rod (101); An ankle-foot connector (105), the ankle-foot connector (105) being located between the fisheye bearing (104) and the bionic arch mechanism (5), the first threaded section being threaded with the ankle-foot connector (105) through the through hole, extending from the connecting through hole (510) on the side wall of the ankle-foot connector (51), and being mounted and fixed to the bionic arch mechanism (5) via a locking connection assembly; The heel recognition module (2) comprises: A flexible shoe (202), wherein the heel of the flexible shoe (202) is fixed to the upper surface of the bionic arch mechanism (5), and the flexible shoe (202) is used to contact the wearer's foot to form foot support; a plantar pressure sensor (203), the plantar pressure sensor (203) being mounted in a first countersunk hole (511) at the bottom of the ankle-foot connecting section (51) via a first floating structure; The first floating structure comprises: A heel sensor mounting box (205) is connected to a side of the plantar pressure sensor (203) away from the first countersunk hole (511), and the heel sensor mounting box (205) is connected to the ankle-foot connecting section (51) via a first positioning screw (206); the first positioning screw (206) has a second optical axis section and a second threaded section, the second optical axis section is used to be connected to the heel sensor mounting box (205), and the second threaded section is connected to the bottom of the ankle-foot connecting section (51) via the heel sensor mounting box (205); the heel sensor mounting box (205) can move along the axis direction of the first positioning screw (206) relative to the bionic arch mechanism (5) to eliminate the tension applied to the heel sensor mounting box (205) during walking.

2. The exoskeleton bionic ankle system according to claim 1, which takes into account the temporal and spatial characteristics of human gait, is characterized in that: The toe recognition module (3) comprises: A forefoot connecting member (302), the forefoot connecting member (302) being arranged at the toe portion of the bottom of the flexible shoe (202), and the end portion thereof being connected to the end portion of the foot connecting section (52); a second sink hole (3021) being arranged on a side of the forefoot connecting member (302) away from the flexible shoe (202), the second sink hole (3021) being provided with a toe pressure sensor (305) via a second floating structure, the toe pressure sensor (305) being used to collect toe pressure of the wearer; The second floating structure comprises: A toe sensor mounting box (303) is connected to a side of a toe pressure sensor (305) away from a forefoot connector (302), and the toe sensor mounting box (303) is connected to the forefoot connector (302) via a second positioning screw; the second positioning screw has a third optical axis section and a third threaded section, the third optical axis section is used to be connected to the toe sensor mounting box (303), and the third threaded section is connected to the bottom of the flexible shoe (202) via the toe sensor mounting box (303); the toe sensor mounting box (303) can move relative to the flexible shoe (202) along the axis direction of the second positioning screw to eliminate the tension applied to the toe sensor mounting box (303) during walking.

3. The exoskeleton bionic ankle system according to claim 2, which takes into account the temporal and spatial characteristics of human gait, is characterized in that: The end of the foot connection section (52) is provided with two corresponding raised structures (521), and the raised structure (521) comprises two semicircular raised portions arranged from top to bottom; the two semicircular raised portions are arranged concentrically, and the radius of the semicircular raised portion located on top is smaller than the radius of the other semicircular raised portion; A first mounting hole (5211) is provided on the protruding structure (521), and a connecting hole (3022) matching the first mounting hole (5211) is provided at the end of the forefoot connecting member (302). The first mounting hole (5211) and the connecting hole (3022) cooperate with the metatarsophalangeal joint motion module (4) to movably connect the foot connecting section (52) and the forefoot connecting member (302). The metatarsophalangeal joint motion module (4) is used to simulate the flexion and extension degrees of freedom of the metatarsophalangeal joint of the human body and limit the range of motion of the forefoot connecting member (302).

4. The exoskeleton bionic ankle system according to claim 3, wherein: The protruding structure (521) is further provided with a second mounting hole (5212), the second mounting hole (5212) being located below the first mounting hole (5211) and being arranged concentrically with the first mounting hole (5211); the end of the forefoot connecting member (302) for connecting to the protruding structure (521) is provided with a limiting protrusion (3023); The metatarsophalangeal joint motion module (4) comprises: A first elastic card (404) and a first pin (401) cooperate with each other, the connecting hole (3022) and the first mounting hole (5211) are connected via the first elastic card (404) and the first pin (401), and the forefoot connector (302) and the bionic arch mechanism (5) can rotate relative to each other along the axis of the first pin (401), thereby realizing the degree of freedom of the wearer's metatarsophalangeal joint; A second pin shaft (405) and a second elastic card (403) cooperate with each other, wherein the second pin shaft (405) is fixed between the two second mounting holes (5212) via the second elastic card (403), and the second pin shaft (405) limits the range of motion of the forefoot connector (302) by cooperating with the limiting protrusion (3023).

5. The exoskeleton bionic ankle system according to claim 4, which takes into account the temporal and spatial characteristics of human gait, is characterized in that: The bottom of the ankle-foot connection section (51) and the bottom of the flexible shoe (202) are also provided with a rubber sole (207) and a rubber toe (304), respectively; and the bottom of the bionic arch mechanism (5) is provided with a gasket (402).

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