Bionic self-adaptive anti-subsidence walking wheel and control method thereof

Abstract

The invention provides a bionic self-adaptive anti-subsidence walking wheel and a control method thereof. The bionic self-adaptive anti-subsidence walking wheel comprises a walking wheel flange plate, walking wheel leg and foot single bodies, a pose sensing system and a controller. A plurality of walking wheel leg and foot single bodies are arranged on the walking wheel flange plate in the circumferential direction; each walking wheel leg and foot single body comprises a bionic tendon-bone cooperation mechanism and a bionic tendon driving mechanism; the bionic tendon driving mechanism can open and close the bionic tendon-bone cooperation mechanism; the pose sensing system is used for detecting a height signal from a walking wheel flange plate to the ground and transmitting the height signal to the controller; and the controller compares the height signal with a preset value and controls the bionic tendon driving mechanism to open and close the bionic tendon-bone cooperation mechanism according to a comparison result. Self-adaptive opening and closing of the toe web of the bionic walking wheel are achieved, the walking wheel leg and foot single body is simple in overall structure, the adaptability and application universality of the walking wheel are improved, and the walking wheel can be applied to a robot to improve the trafficability of the robot on the soft ground.

Description

Technical Field

[0001] The invention belongs to the technical field of engineering bionics, and in particular relates to a bionic adaptive anti-sinking walking wheel and a control method thereof. Background Art

[0002] Paddy fields are an important high-quality arable land resource in my country. Paddy fields are highly stable, have good natural endowment conditions, and have a high quality level. Paddy fields are not only an important guarantee for food security, but also play an important role in maintaining regional ecological security and promoting the construction of ecological civilization. Due to the poor bearing and shear resistance of soft ground such as paddy fields, conventional wheels are prone to large subsidence and wet adhesion when in contact with their surfaces, and on the other hand, they are prone to large water-pushing resistance, resulting in large ground loss and excessive disturbance of the ground. In addition, production practice urgently needs paddy field conservation tillage technology that reduces costs, protects soil structure, and protects the environment. Therefore, solving the problems of subsidence and energy consumption on soft ground such as paddy fields is particularly critical to improving economic benefits.

[0003] Mallards live in paddy fields, lakes, rivers, tidal flats and other soft ground areas all year round, and have acquired anti-sinking movement characteristics. As an actuator in direct contact with the ground, the mallard foot is mainly composed of three toes with webbed feet between the toes. The structural morphology of the toes-webs, the ground contact / leave posture, and material assembly play an important role in the anti-sinking process. The existing imitation mallard foot can achieve the function of energy saving and vibration reduction through the imitation tendon unit, but in actual use, the existing imitation mallard foot has a strong adhesion to the ground when it leaves the ground and is not easy to get rid of. In addition, due to the fixed shape and structure of the duck foot and the large surface area, it leads to high air resistance and high energy consumption. Summary of the invention

[0004] In response to the above technical problems, the present invention provides a bionic adaptive anti-sinking walking wheel and a control method thereof, which realizes the adaptive opening and closing of the toe webs of the bionic walking wheel. The overall structure of the leg and foot monomer of the walking wheel is simple, which improves the adaptability and wide application of the walking wheel. When used on robots, it is beneficial to improve their passability on soft ground.

[0005] Note that the description of these objectives does not prevent the existence of other objectives. One embodiment of the present invention does not need to achieve all of the above objectives. Objectives other than the above objectives can be extracted from the description of the specification, drawings, and claims.

[0006] Mallards walk mainly through the second, third, and fourth toes, which are placed forward and from inside to outside, and the webbed feet between the toes. The feet of mallards are mainly composed of tarsometatarsal bones and phalanges. When touching the ground, the second and fourth toes open and drive the webbed feet between the toes to open, increasing the ground contact area; when leaving the ground, the phalanges leave the ground from the heel, reducing the adhesion force and disturbance to the ground; when swinging, the webbed feet close, reducing the resistance of water and air to the feet when moving forward. The complex tendon system of the mallard's hind limbs provides movement and power sources for its walking or running through muscles, and provides traction for the movement of other parts through long and light tendons. The muscles are mainly distributed on the femur and tibiotarsal bones. There are fewer muscles on the bones below the tarsal joints, and the movement of its bones is almost entirely driven by tendon traction, which reduces the weight and volume of the tarsometatarsal bones and soles of the feet with a large swing amplitude, thereby providing a guarantee for the mallard to maintain long-lasting performance during walking or swimming.

[0007] Tendon is a tough connective tissue band that connects muscle and bone, bears tension, and is composed of collagen. Tendons work together with muscles to produce movement. The tendon tissue of the mallard foot is clearly divided into tendon bundles and tendon endotendon, and the cross-section of a single tendon is cylindrical. Through a scanning electron microscope, the tendon is observed from the outer surface, and it can be seen that the tendon is composed of many tertiary fiber bundles. The layer of fine connective tissue wrapped around the tendon is called the tendon outer layer. The average diameter of the tendon is about 1-2mm. From the cross-section of the tendon, the incision is smooth, the collagen fiber bundles are closely arranged, and the cracks show that the tertiary fiber bundles of the tendon are composed of many secondary fiber bundles. The longitudinal section shows that many secondary fiber bundles are roughly arranged in parallel, and the diameter of the secondary fiber bundles is about 0.2μm. In addition, there are staggered collagen fiber bundles in a mesh structure, which will help to enhance the strength of the tendon in all directions. The secondary fiber bundles are composed of many primary collagen fiber bundles, which are closely arranged to form a layered structure. The primary, secondary, and tertiary fiber bundles are surrounded by a connective tissue sheath called the internal tendon, which helps the fiber bundles slide over each other during tendon movement.

[0008] When the mallard walks or runs, the extensor tendons on the dorsal side of the foot and the flexor tendons on the plantar side work perfectly together to achieve the bending and extension of the toes. The metatarsophalangeal joint has a relatively thin support band, which is distributed on the plantar and dorsal sides, to help change the direction of tendon force transmission and constrain the position of the tendon. When the mallard's foot just touches the ground, the extensor tendons are pulled by the muscles, while the flexor tendons relax, so the toes are in a straight state. When the foot is in the middle of the ground contact, the extensor tendons continue to be pulled by the muscles and continue to be stretched. Due to the action of the pulley of the metatarsophalangeal joint, the flexor tendons stretch the muscles in the opposite direction, and the toes continue to remain in a straight state; when the foot leaves the ground, the extensor tendons gradually relax, and the flexor tendons gradually receive muscle tension, so the toes gradually bend.

[0009] The present invention achieves the above technical objectives through the following technical means.

[0010] A bionic adaptive anti-sinking walking wheel, comprising a walking wheel flange, a walking wheel leg and foot monomer, a posture sensing system and a controller;

[0011] The walking wheel flange is provided with a plurality of walking wheel leg-foot monomers along the circumferential direction;

[0012] The walking wheel leg-foot monomer comprises a bionic tendon-bone coordination mechanism and a bionic tendon driving mechanism; the bionic tendon driving mechanism is arranged on the bionic tendon-bone coordination mechanism, and the bionic tendon driving mechanism can open and close the bionic tendon-bone coordination mechanism;

[0013] The posture sensing system is installed on the walking wheel flange to monitor the height signal from the walking wheel flange to the ground and transmit it to the controller;

[0014] The controller is connected to the posture sensing system and the bionic tendon driving mechanism respectively. The controller compares the height signal with a preset value, and controls the bionic tendon driving mechanism to open and close the bionic tendon-bone coordination mechanism according to the comparison result.

[0015] In the above scheme, the bionic tendon-bone coordination mechanism includes a bionic metatarsal bone, a bionic extensor tendon, a bionic flexor tendon, a bearing support, a bionic second toe, a bionic third toe, a bionic fourth toe, a bionic webbed foot and a base;

[0016] The bearing support is arranged on the base, and the simulated tarsometatarsus is sleeved on the bearing support. The simulated flexor tendon is divided into left and right ends below, one end of the simulated flexor tendon is connected to the simulated second toe, the other end of the simulated flexor tendon is connected to the simulated fourth toe, and the upper part of the simulated flexor tendon is connected to the rear side of the simulated tarsometatarsus; the simulated extensor tendon is divided into left and right ends below, one end of the simulated extensor tendon is connected to the simulated second toe, the other end of the simulated extensor tendon is connected to the simulated fourth toe, and the upper part of the simulated extensor tendon is connected to the front side of the simulated tarsometatarsus; the simulated second toe, the simulated fourth toe, and the simulated third toe are respectively connected to the base, and the simulated second toe and the simulated fourth toe are respectively located on both sides of the simulated third toe; the bionic web is located at the bottom of the simulated second toe, the simulated fourth toe, and the simulated third toe, the middle part of the bionic web is connected to the simulated third toe, and the two sides of the bionic web are respectively connected to the simulated second toe and the simulated fourth toe.

[0017] In the above scheme, the bionic tendon driving mechanism includes an extensor tendon driving motor and a flexor tendon driving motor; the extensor tendon driving motor is installed on the front side of the tarsometatarsal bone, and the power output shaft of the extensor tendon driving motor is connected to the extensor tendon, which is used to pull the extensor tendon to drive the second toe and the fourth toe and the bionic webbed between the toes to close;

[0018] The simulated flexor tendon driving motor is installed at the rear side of the simulated tarsometatarsal bone, and the power output shaft of the simulated flexor tendon driving motor is connected to the simulated flexor tendon, so as to pull the simulated flexor tendon to drive the second toe and the fourth toe and the bionic webbed foot between the toes to open;

[0019] The controller is connected to the extensor tendon driving motor and the flexor tendon driving motor respectively; the controller compares the height signal of the posture sensing system with the preset value, and issues instructions according to the comparison result to control the extensor tendon driving motor and the flexor tendon driving motor to make corresponding actions, so that the bionic tendon-bone cooperative mechanism opens and closes.

[0020] In the above scheme, when the walking wheel leg and foot monomer touch the ground, the height from the walking wheel flange to the ground monitored by the posture sensing system is lower than the preset value, and the controller controls the extensor tendon driving motor to rotate in the reverse direction to release the extensor tendon, and controls the flexor tendon driving motor to rotate forward, pulling the flexor tendon to drive the second toe and the fourth toe to move outward, thereby opening the bionic web between the toes;

[0021] When the walking wheel leg and foot unit starts to leave the ground, the height from the walking wheel flange to the ground monitored by the posture sensing system is higher than the preset value, and the controller controls the flexor tendon drive motor to rotate in the opposite direction to release the flexor tendon, and controls the extensor tendon drive motor to rotate forward, pulling the extensor tendon to drive the second toe and the fourth toe to move inward, thereby closing the bionic web between the toes to reduce the disturbance and resistance when leaving the ground.

[0022] In the above solution, the posture perception system is a ranging sensor.

[0023] In the above scheme, the extensor tendon-like structure is a fiber braided structure, including a fiber rope structure, a flexible telescopic structure and a shell;

[0024] The fiber rope structure comprises a plurality of bundles of longitudinally spirally arranged fibers and transversely arranged fibers, and the longitudinally spirally arranged fibers and the transversely arranged fibers are interlaced and woven into the fiber rope structure;

[0025] The flexible telescopic structure comprises a plurality of springs, and the plurality of springs are arranged to form the flexible telescopic structure;

[0026] The fiber rope structure and the flexible telescopic structure are longitudinally arranged and connected to form a bionic tendon unit. A plurality of bionic tendon units are longitudinally arranged and wrapped with a nylon shell to form an extensor tendon. The extensor tendon and the flexor tendon have the same structure.

[0027] In the above scheme, a first limiting mechanism and a second limiting mechanism are respectively provided on both sides of the bearing support; the first limiting mechanism is higher than the second limiting mechanism, and the first limiting mechanism is used to limit the minimum angle between the simulated tarsometatarsus and the simulated third toe; the second limiting mechanism is used to limit the maximum angle between the simulated tarsometatarsus and the simulated third toe.

[0028] In the above scheme, a first slide groove and a second slide groove are arranged on the base; the first slide groove is distributed on one side of the second toe, and the second slide groove is distributed on one side of the fourth toe. The first slide groove and the second slide groove are symmetrically distributed along the axis of the simulated tarsometatarsus. One side of the starting end of the simulated flexor tendon bypasses the first slide groove, and the other side of the starting end of the simulated flexor tendon bypasses the second slide groove, and then they merge and bypass the reserved hole of the simulated flexor tendon set on the simulated third toe, and are connected to the rear side of the simulated tarsometatarsus above.

[0029] A control method according to the bionic adaptive anti-sinking walking wheel comprises the following steps:

[0030] The posture sensing system monitors the height signal from the walking wheel flange to the ground and transmits it to the controller;

[0031] The controller compares the height signal with a preset value, and controls the bionic tendon driving mechanism to open and close the bionic tendon-bone coordination mechanism according to the comparison result;

[0032] When the walking wheel leg and foot monomer touches the ground, and the height from the walking wheel flange to the ground monitored by the posture sensing system is lower than the preset value, the controller controls the extensor tendon driving motor to rotate in the reverse direction to release the extensor tendon, and controls the flexor tendon driving motor to rotate forward, pulling the flexor tendon to drive the second toe and the fourth toe to move outward, thereby opening the bionic web between the toes;

[0033] When the walking wheel leg and foot are off the ground, and the height from the walking wheel flange to the ground monitored by the posture sensing system is higher than the preset value, the controller controls the flexor tendon drive motor to rotate in the opposite direction to release the flexor tendon, and controls the extensor tendon drive motor to rotate forward, pulling the extensor tendon to drive the second toe and the fourth toe to move inward, thereby closing the bionic webbed foot between the toes.

[0034] Compared with the prior art, the present invention has the following beneficial effects:

[0035] 1. The bionic tendon-bone coordination mechanism of the present invention drives the bionic tendon driving mechanism to open the toe web after the walking wheel leg-foot unit touches the ground, thereby significantly increasing the ground contact area, reducing the ground pressure, and increasing the ground contact friction; the bionic tendon driving mechanism drives the toe web to close when the walking wheel leg-foot unit leaves the ground, thereby reducing the air resistance encountered by the walking wheel leg-foot unit when swinging, and realizing the adaptive opening and closing effect of the toe web of the bionic walking wheel. The overall structure of the walking wheel leg-foot unit is simple, which improves the adaptability and wide application of the walking wheel. It is beneficial to improve its passability on soft ground when used on robots.

[0036] 2. The bionic tendon formed by imitating the extensor tendon and the flexor tendon in the present invention has a fiber rope structure with longitudinal spirally arranged fibers and transversely arranged fibers interlaced at the lower end of the tendon, imitating the criss-crossed structure of the tendon; the upper end of the tendon is a spring, imitating the energy storage and shock absorption function of the tendon; a nylon shell is added to the surface of the tendon to imitate the protection and smooth effect of the outer layer of the tendon. The unique tendon weaving method achieves the advantages of high strength, flexibility and bendability, and provides buffering and a certain energy recovery effect when the walking wheel leg and foot monomer touches the ground.

[0037] 3. The posture sensing system of the present invention monitors the elevation signal from the walking wheel flange to the ground and transmits it to the controller; the controller compares the height signal with a preset value, and controls the bionic tendon drive mechanism to open and close the bionic tendon-bone coordination mechanism according to the comparison result; through the rigid-flexible coupling of the toes and webs, and the coordinated movement of the tendons and bones, the walking wheel leg-foot monomer can increase the ground contact area when touching the ground to increase friction and increase the anti-sinking effect, and reduce the area when leaving the ground to reduce water and air resistance, while reducing vibration when touching the ground.

[0038] Note that the description of these effects does not prevent the existence of other effects. One embodiment of the present invention does not necessarily have all of the above effects. Effects other than the above can be clearly seen and extracted from the description of the specification, drawings, claims, etc. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 It is a schematic diagram of the walking wheel structure according to one embodiment of the present invention.

[0040] Figure 2 It is a schematic front view of a walking wheel according to an embodiment of the present invention.

[0041] Figure 3 It is a schematic left view of a walking wheel leg and foot monomer in an open toe-web state according to one embodiment of the present invention.

[0042] Figure 4 It is a schematic top view of a walking wheel leg and foot monomer toe-web in an open state according to one embodiment of the present invention.

[0043] Figure 5 It is a schematic front view of a walking wheel leg and foot monomer in an open toe-web state according to one embodiment of the present invention.

[0044] Figure 6 It is a schematic left view of a walking wheel leg and foot monomer in a toe-web closed state according to one embodiment of the present invention.

[0045] Figure 7 It is a schematic top view of a walking wheel leg and foot monomer toe-web closed state according to one embodiment of the present invention.

[0046] Figure 8It is a schematic diagram of a walking wheel leg and foot unit base according to an embodiment of the present invention.

[0047] Fig. 9 It is a schematic top view of a walking wheel leg and foot unit base according to one embodiment of the present invention.

[0048] Fig.10 It is a schematic diagram of a walking wheel leg and foot single-body bearing support according to one embodiment of the present invention.

[0049] Fig.11 It is a schematic diagram of the cross-sectional structure of the tendon-mimicking monomer of a walking wheel leg and foot according to one embodiment of the present invention.

[0050] Fig.12 It is a schematic front view of a single segment of a walking wheel leg-foot monomer tendon-mimicking structure according to one embodiment of the present invention.

[0051] Fig.13 It is a schematic diagram of a multi-segment front view of a single tendon-mimicking structure of a walking wheel leg and foot according to an embodiment of the present invention.

[0052] Fig.14 It is a roadmap of a walking wheel control system according to one embodiment of the present invention.

[0053] In the figure: 1. walking wheel flange; 2. walking wheel leg and foot monomer; 21. bionic tendon-bone coordination mechanism; 211. imitation tarsometatarsus; 212. imitation extensor tendon; 213. imitation flexor tendon; 214. bearing support; 2141. first limiting mechanism; 2142. second limiting mechanism; 215. imitation second toe; 216. imitation third toe; 217. imitation fourth toe; 218. bionic webbed foot; 219. base; 2191. first reserved hole of base; 2192. second reserved hole of base; 22. bionic tendon driving mechanism; 222. imitation extensor tendon driving motor; 223. imitation flexor tendon driving motor; 3. posture sensing system. DETAILED DESCRIPTION

[0054] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and should not be construed as limiting the present invention.

[0055] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "front", "back", "left", "right", "up", "down", "axial", "radial", "vertical", "horizontal", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, the meaning of "multiple" is two or more, unless otherwise clearly and specifically defined.

[0056] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0057] Figure 1-13 The figure shows a preferred embodiment of the bionic adaptive anti-subsidence walking wheel, which comprises a walking wheel flange 1, a walking wheel leg-foot unit 2, a posture sensing system 3 and a controller; the walking wheel flange 1 is provided with a plurality of walking wheel leg-foot units 2 along the circumferential direction; the walking wheel leg-foot unit 2 comprises a bionic tendon-bone coordination mechanism 21 and a bionic tendon driving mechanism 22; the bionic tendon driving mechanism 22 is arranged on the bionic tendon-bone coordination mechanism 21, and the bionic tendon driving mechanism 22 can open and close the bionic tendon-bone coordination mechanism 21; the posture sensing system 3 is installed on the walking wheel flange 1, and is used to monitor the elevation signal from the walking wheel flange 1 to the ground, and transmit it to the controller; the controller is connected to the posture sensing system 3 and the bionic tendon driving mechanism 22 respectively, and the controller compares the height signal with the preset value, and controls the bionic tendon driving mechanism 22 to open and close the bionic tendon-bone coordination mechanism 21 according to the comparison result.

[0058] The bionic tendon-bone coordination mechanism 21 includes a simulated tarsometatarsal bone 211, a simulated extensor tendon 212, a simulated flexor tendon 213, a bearing support 214, a simulated second toe 215, a simulated third toe 216, a simulated fourth toe 217, a bionic webbed foot 218 and a base 219; the bearing support 214 is arranged on the base 219, the simulated tarsometatarsal bone 211 is sleeved on the bearing support 214 by bolts, the simulated flexor tendon 213 is divided into left and right ends below, one end of the simulated flexor tendon 213 is connected to the simulated second toe 215, the other end of the simulated flexor tendon 213 is connected to the simulated fourth toe 217, the simulated flexor tendon 213 is connected to the rear side of the simulated tarsometatarsal bone 211 above; the simulated extensor tendon 212 is divided into left and right ends below The simulated second toe 215, the simulated fourth toe 217 and the simulated third toe 216 are connected to the simulated third toe 216 at the upper end, one end of the simulated extensor tendon 212 is connected to the simulated second toe 215, the other end of the simulated extensor tendon 212 is connected to the simulated fourth toe 217, and the upper part of the simulated extensor tendon 212 is connected to the front side of the simulated tarsometatarsal 211; the simulated second toe 215, the simulated fourth toe 217 and the simulated third toe 216 are respectively connected to the base 219, and the simulated second toe 215 and the simulated fourth toe 217 are respectively located on both sides of the simulated third toe 216; the bionic web 218 is located at the bottom of the simulated second toe 215, the simulated fourth toe 217 and the simulated third toe 216, the middle part of the bionic web 218 is connected to the simulated third toe 216, and the two sides of the bionic web 218 are respectively connected to the simulated second toe 215 and the simulated fourth toe 217.

[0059] The imitation second toe 215 is an imitation of the second toe of a mallard, the imitation third toe 216 is an imitation of the third toe of a mallard, and the imitation fourth toe 217 is an imitation of the fourth toe of a mallard.

[0060] The simulated second toe 215, simulated third toe 216 and simulated fourth toe 217 are all connected to the base 219, wherein the simulated second toe 215 and the simulated fourth toe 217 can rotate inward or outward around the hinge to realize the opening and closing of the web, and the simulated third toe 216 and the base 219 remain relatively still, serving as the main support and fulcrum of the foot.

[0061] The bionic tendon driving mechanism 22 includes a bionic extensor tendon driving motor 222 and a bionic flexor tendon driving motor 223; the bionic extensor tendon driving motor 222 is installed on the front side of the bionic tarsometatarsal bone 211, and the power output shaft of the bionic extensor tendon driving motor 222 is connected to the bionic extensor tendon 212, and is used to pull the bionic extensor tendon 212 to drive the second toe 215 and the fourth toe 217 and the bionic webbed foot 218 between the toes to close; the bionic flexor tendon driving motor 223 is installed on the rear side of the bionic tarsometatarsal bone 211, and the power output shaft of the bionic flexor tendon driving motor 223 is connected to the bionic extensor tendon 212, and is used to pull the bionic extensor tendon 212 to drive the second toe 215 and the fourth toe 217 and the bionic webbed foot 218 between the toes to close; The output shaft is connected to the simulated flexor tendon 213, and is used to pull the simulated flexor tendon 213 to drive the second toe 215, the fourth toe 217 and the inter-toe bionic web 218 to open; the controller is respectively connected to the simulated extensor tendon drive motor 222 and the simulated flexor tendon drive motor 223; the controller compares the height signal of the posture sensing system 3 with the preset value, and issues instructions according to the comparison result to control the simulated extensor tendon drive motor 222 and the simulated flexor tendon drive motor 223 to make corresponding actions, so that the bionic tendon-bone coordination mechanism 21 opens and closes.

[0062] When the walking wheel leg-foot monomer 2 touches the ground, the height of the walking wheel flange 1 to the ground monitored by the posture sensing system 3 is lower than the preset value, and the controller controls the extensor tendon driving motor 222 to rotate in the reverse direction to release the extensor tendon 212, and controls the flexor tendon driving motor 223 to rotate forward, pulling the flexor tendon 213 to drive the second toe 215 and the fourth toe 217 to move outward, thereby opening the bionic webbed foot 218 between the toes to prevent the walking wheel from sinking further;

[0063] When the walking wheel leg-foot unit 2 starts to leave the ground, the elevation of the walking wheel flange 1 to the ground monitored by the posture sensing system 3 is higher than the preset value, and the controller controls the flexor tendon driving motor 223 to rotate in the opposite direction to release the flexor tendon 213, and controls the extensor tendon driving motor 222 to rotate forward, pulling the extensor tendon 212 to drive the second toe 215 and the fourth toe 217 to move inward, thereby closing the bionic webbed foot 218 between the toes to reduce the disturbance and resistance of leaving the ground.

[0064] Preferably, when the walking wheel leg-foot unit 2 touches the ground, if the actual height of the walking wheel is monitored to decrease, the controller will send a signal to the flexor tendon driving motor 223 to rotate it, thereby pulling the flexor tendon 213 to drive the second toe 215 and the fourth toe 217 as well as the bionic webbed foot 218 between the toes to open, thereby preventing the walking wheel from sinking further; conversely, when it is monitored that the actual height of the walking wheel begins to increase, it means that the walking wheel leg-foot unit 2 begins to leave the ground. At this time, the controller will send a signal to the extensor tendon driving motor 222 to rotate it, thereby pulling the extensor tendon 212 to drive the second toe 215 and the fourth toe 217 as well as the bionic webbed foot 218 between the toes to close, thereby reducing the ground disturbance and resistance.

[0065] Preferably, the initial angle ° of the simulated tarsal phalanx 211 and the simulated third toe 223 is 120° to 140°, thereby reducing the closed area and reducing the water and air resistance when the walking wheel leg foot unit 2 swings. Further, the minimum angle ° of the simulated tarsal phalanx 211 and the simulated second toe 223 is 90°, thereby ensuring that the walking wheel leg foot unit 2 has greater support and traction when touching the ground, reducing the amount of sinking.

[0066] Preferably, the posture perception system 3 is a ranging sensor.

[0067] The bearing support 214 is provided with a first limiting mechanism 2141 and a second limiting mechanism 2142 on both sides respectively; the first limiting mechanism 2141 is higher than the second limiting mechanism 2142, and the first limiting mechanism 2141 is used to limit the minimum angle between the simulated tarsometatarsal bone 211 and the simulated third toe 216; the second limiting mechanism 2142 is used to limit the maximum angle between the simulated tarsometatarsal bone 211 and the simulated third toe 216.

[0068] Preferably, the first limiting mechanism 2141 limits the angle between the simulated tarsometatarsal bone 211 and the simulated third toe 216 to 90 degrees; the second limiting mechanism 2142 limits the angle between the simulated tarsometatarsal bone 211 and the simulated third toe 216 to 130 degrees.

[0069] The base 219 is provided with a first slide groove 2191 and a second slide groove 2192. The first slide groove 2191 is distributed on one side of the second toe 215, and the second slide groove 2192 is distributed on one side of the fourth toe 217. The first slide groove 2191 and the second slide groove 2192 are symmetrically distributed along the axis of the simulated tarsometatarsus 211. The starting end of the simulated flexor tendon 213 bypasses the first slide groove 2191 on the left side, and the starting end of the simulated flexor tendon 213 bypasses the second slide groove 2192 on the right side, passes through the rear side of the base, and then merges and bypasses the simulated flexor tendon reserved hole 2161 set on the simulated third toe 216, and is connected to the rear side of the simulated tarsometatarsus 211 above.

[0070] Preferably, in order to simulate the opening and closing angle limit of the webbed toes, the simulated extensor tendon 212 and the simulated flexor tendon 213 are made of elastic materials. After the simulated tarsometatarsal bone 211 rotates, the simulated flexor tendon 213 is tightened to drive the simulated second toe 215 and the simulated fourth toe 217 to open relative to the simulated third toe 216. Under the limiting effect of the first limiting mechanism 2141 of the bearing base, the angle between the simulated tarsometatarsal bone 211 and the simulated third toe 216 is reduced to 90 degrees, and the simulated flexor tendon 213 no longer moves. When the walking wheel leg and foot leave the ground, the simulated tarsometatarsal 211 gradually returns to its original position, the simulated extensor tendon 212 relaxes, the simulated flexor tendon 213 gradually tightens, and the simulated second toe 215 and the simulated fourth toe 217 gradually return to their original position under the action of the simulated flexor tendon 213. Under the limiting action of the second limiting mechanism 2142 of the bearing base, after the angle between the simulated tarsometatarsal 211 and the simulated third toe 216 expands to 130 degrees, the simulated extensor tendon 212 is no longer tightened.

[0071] Preferably, the simulated second toe 215, the simulated third toe 216, and the simulated fourth toe 217 are in a straight state, so that the pressure on the ground gradually moves forward when leaving the ground, reducing the disturbance to the soil, reducing soil adhesion, improving the smoothness and stability of the walking wheel leg-foot unit 2 when walking, and improving the anti-sinking ability of the walking wheel leg-foot unit 2.

[0072] Preferably, the bionic fin 218 is made of high-performance thermoplastic copolyester TPC. In order to imitate the distribution of the mallard webbed feet, the bionic fin 218 is glued to the bottom of the imitation second toe 215, the imitation third toe 216, and the imitation fourth toe 217, so as to provide a larger contact area when contacting the ground; in order to imitate the high elasticity and foldable effect of the thin-sheet webbed feet, a high-performance thermoplastic copolyester TPC with a thickness of 1 mm is used.

[0073] Preferably, the toe bone is made of aluminum alloy.

[0074] Preferably, the simulated extensor tendon 212 adopts a structure divided into two parts in order to imitate the structure of the extensor tendon of the mallard duck, and is respectively connected to the second toe 215 and the fourth toe 217; the simulated flexor tendon 213 adopts a structure divided into two parts in order to imitate the structure of the flexor tendon of the mallard duck, and is respectively connected to the second toe 215 and the fourth toe 217.

[0075] The extensor tendon 212 is a fiber braided structure, including multiple bundles of fibers 2121 arranged in a longitudinal spiral and fibers 2122 arranged in a transverse direction. The fibers 2121 arranged in a longitudinal spiral and the fibers 2122 arranged in a transverse direction are interlaced and woven into a fiber rope structure 2124, which imitates the arrangement and distribution of the fiber bundles of the mallard's foot tendon; multiple springs 2123 are arranged to form a flexible telescopic structure 2125, which imitates the energy storage and shock absorbing effect of the fiber bundles of the mallard's foot tendon; the fiber rope structure 2124 and the flexible telescopic structure 2125 are arranged in a longitudinal direction and connected by gluing or hanging to form a bionic tendon unit 2126; multiple bionic tendon units 2126 are arranged in a longitudinal direction and wrapped with a nylon shell 2127 to form the extensor tendon 212. The extensor tendon 212 and the flexor tendon 213 have the same structure.

[0076] Preferably, the simulated third toe 216 is mainly a supporting toe, which is beneficial to the balance of the walking wheel leg and foot monomer.

[0077] Preferably, the bionic fin 218 in the bionic tendon-bone coordination mechanism 21 is made of flexible material, and the rest is made of rigid material. The rigid material and the flexible material together form a rigid-flexible coupling bionic design. Through the rigid-flexible coupling bionic design, when the walking wheel leg-foot monomer 2 touches the ground, the bionic tendon-bone coordination mechanism 21 increases the ground contact area to play an anti-sinking role, and reduces the area when leaving the ground to reduce air resistance; the bionic tendon driving mechanism 22 reduces the disturbance and damage to the ground; the bionic fin 218 reduces the vibration when touching the ground. The present invention can be applied to paddy field operation vehicles such as traditional rice transplanters to improve the vehicle's driving speed, anti-sinking performance and reduce damage to the ground, and has practical application value.

[0078] The engineering bionic principle of the present invention:

[0079] The present application uses the foot of a mallard as a bionic prototype. Mallards are semi-aquatic birds with good walking ability on soft ground such as paddy fields and tidal flats, which is mainly due to the combined action and movement of their second to fourth toes and the webbed feet between the toes. During the process of touching the ground, the pressure is distributed on the webbed feet with a larger area, so the amount of sinking is very small; when leaving the ground, the toe bones leave the ground one by one, so the adhesion is very small; the webbed feet are closed during the swinging period after leaving the ground, so the air resistance is very small. When walking or running, the extensor tendons and flexor tendons of the mallard work in coordination to achieve the bending and extension of the toes. Based on the above characteristics of the mallard foot, the present invention starts with a biological prototype and focuses on the design of a bionic tendon-bone coordination mechanism 21 and a bionic tendon driving mechanism 22, providing new design ideas and reference solutions for the design of walking mechanisms on soft ground such as paddy fields.

[0080] When the mallard's foot touches the ground, the toes touch the ground first, followed by the entire palm. The second and fourth toes drive the webs between the toes to open. The third toe, which is the longest, touches the ground first. Then the sole of the foot rotates around the tip of the third toe and lands quickly. During the ground contact, the tarsometatarsus gradually rotates forward around the metatarsophalangeal joint, so the metatarsophalangeal joint angle decreases; during the lift-off process, the metatarsophalangeal joint is lifted due to the lifting of the tarsal bones, so the hind sole begins to leave the ground, and the metatarsophalangeal joint angle gradually increases. Each segment of the phalanges leaves the ground one by one starting from the proximal phalanx until the distal phalanx leaves the ground, completing the lift-off process; during the swing phase, the second and fourth toes gradually begin to close and drive the webs to close, and straighten the toes before the next step of touching the ground, driving the webs to open, thus completing a stride cycle.

[0081] like Figure 7As shown, in order to imitate the mallard's foot opening the web when the second and fourth toes touch the ground and closing the web after leaving the ground, a bionic tendon-bone coordination mechanism 21 is designed. Through the monitoring of the altitude by the posture sensing system 3 during the contact process, the simulated flexor tendon driving motor 223 pulls the simulated flexor tendon 213 to tighten, thereby driving the simulated second toe 215 and the simulated fourth toe 217 to open outward, and then the bionic webbed foot 218 is driven to open by the simulated second toe 215 and the fourth toe 217, and the contact area is increased, which increases the anti-sinking performance of the bionic foot; during the leave-off process, the simulated extensor tendon driving motor 222 pulls the simulated extensor tendon 212 to tighten, thereby driving the simulated second toe 215 and the simulated fourth toe 217 to close inward, and then the bionic webbed foot 218 is driven to close by the simulated second toe 215 and the fourth toe 217, and the contact area is reduced, which reduces the water and air resistance when the walking wheel leg and foot monomer moves.

[0082] The mallard has a complex tendon system in its hind limbs, which uses muscles to provide power for walking and running, while long and light tendons provide traction for movement in other parts. The muscles are mainly concentrated on the femur and tibiotarsal bones, and there are fewer muscles below the tarsal joints. Movement mainly relies on tendon traction, which reduces the weight of the tarsometatarsal bones and the soles of the feet, and improves the mallard's endurance when walking and swimming. Tendons are connective tissues composed of collagen, connecting muscles to bones and bearing tension. The tendon tissue of the mallard is divided into tendon bundles and endotendon membranes, and the tendon bundles are composed of collagen fibers. The tendon has a diameter of about 1-2mm and a complex internal structure. The primary fiber bundles are closely arranged to form secondary fiber bundles, and the secondary fiber bundles are roughly arranged in parallel to form tertiary fiber bundles. The tertiary fiber bundles are arranged and combined into a cylindrical outer layer wrapped with the tendon outer layer to form the tendon. This multi-level structure significantly enhances the strength of the tendon. When walking or running, the mallard's extensor tendons and flexor tendons work in coordination to achieve the bending and extension of the toes. The support band of the metatarsophalangeal joint helps change the direction of tendon force and constrain its position. When the foot just touches the ground, the extensor tendons are stretched and the flexor tendons relax, and the toes are straightened; in the middle of the ground contact, the extensor tendons continue to be stretched, the flexor tendons stretch in the opposite direction, and the toes remain straight; when leaving the ground, the extensor tendons relax, the flexor tendons are stretched, and the toes gradually bend.

[0083] In order to imitate the mallard's foot driven by muscles and pulling tendons to move, a bionic tendon driving mechanism 22 is designed, which completely corresponds to the mallard's foot structure, realizes the adaptive perception function of road conditions, and enhances the actual passing performance of the walking wheel. In order to imitate the mallard's foot tendon's multi-level and multi-bundle structure, high strength, low sliding resistance, energy storage and shock absorption, etc., a bionic tendon is designed with a multi-strand braided and elastic telescopic structure. In order to imitate the arrangement and distribution of the mallard's foot tendon fiber bundles, longitudinally spirally arranged fibers 2121 and transversely arranged fibers 2122 are designed to form a fiber rope structure 2124; in order to imitate the energy storage and shock-absorbing effect of the mallard's foot tendon fiber bundles, a large number of springs 2123 are designed to be arranged to form a flexible telescopic structure 2125, and the fiber rope structure 2124 and the flexible telescopic structure 2125 are connected by gluing or hanging to form a bionic tendon unit 2126. Many bionic tendon units 2126 are arranged longitudinally. In order to imitate the smooth surface and low sliding resistance of the mallard's foot tendon, a nylon shell 2127 is designed to wrap the outside of the bionic tendon unit to form a bionic extensor tendon 212, which greatly improves the structural strength of the bionic tendon and improves the flexibility and low sliding resistance of the mallard's webbed foot drive.

[0084] Working process:

[0085] When the walking wheel leg foot monomer 2 touches the ground, due to the relatively forward center of gravity and the initial angle of the simulated metatarsophalangeal joint, the toe of the walking wheel leg foot monomer 2 touches the ground first, and then the whole palm touches the ground, and the simulated flexor tendon driving motor 223 is pulled to stretch the simulated flexor tendon 213 backward, and at the same time, the simulated second toe 215 and the simulated fourth toe 217 are pulled to open outward, and the opening of the simulated second toe 215 and the simulated fourth toe 217 drives the bionic fin 218 to open, thereby increasing the ground contact area and reducing the amount of sinking;

[0086] When the walking wheel leg foot monomer 2 starts to leave the ground, the extensor tendon driving motor 222 is used to pull the extensor tendon 212 to stretch backward, and at the same time, the second toe 215 and the fourth toe 217 are pulled inward to close. The closing of the second toe 215 and the fourth toe 217 drives the bionic fin 218 to close, so that the area of ​​the bionic fin 218 is reduced, and the contact area with the ground is gradually reduced, thereby reducing the adhesion force of leaving the ground and the disturbance to the ground;

[0087] When the walking wheel leg foot monomer 2 swings, the extensor tendon driving motor 222 is used to pull the extensor tendon 212 to stretch backward, and the second toe 215 and the fourth toe 217 are gradually closed, so that the area of ​​the bionic fin 218 is minimized, and the contact area with water and air is also minimized. At the same time, the bionic fin 218 is closed to release elastic potential energy, and the closure of the bionic fin 218 is achieved, thereby reducing the resistance of the foot when moving forward in water and air. At this point, the walking wheel leg foot monomer 2 completes a stride cycle. The walking wheel leg foot monomer 2 alternately contacts the ground, thereby achieving the rolling forward of the walking wheel.

[0088] like Fig.14 As shown, a control method according to the bionic adaptive anti-sinking walking wheel comprises the following steps:

[0089] The posture sensing system 3 monitors the elevation signal from the walking wheel flange 1 to the ground and transmits it to the controller;

[0090] The controller compares the height signal with a preset value, and controls the bionic tendon driving mechanism 22 to open and close the bionic tendon-bone coordination mechanism 21 according to the comparison result;

[0091] When the walking wheel leg-foot monomer 2 touches the ground, and the height from the walking wheel flange 1 to the ground monitored by the posture sensing system 3 is lower than a preset value, the controller controls the extensor tendon driving motor 222 to rotate in the reverse direction to release the extensor tendon 212, and controls the flexor tendon driving motor 223 to rotate forward, pulling the flexor tendon 213 to drive the second toe 215 and the fourth toe 217 to move outward, thereby opening the inter-toe bionic web 218 to prevent the walking wheel from sinking further;

[0092] When the walking wheel leg-foot unit 2 leaves the ground, the elevation of the walking wheel flange 1 to the ground monitored by the posture sensing system 3 is higher than a preset value, and the controller controls the flexor tendon driving motor 223 to rotate in the opposite direction to release the flexor tendon 213, and controls the extensor tendon driving motor 222 to rotate forward, pulling the extensor tendon 212 to drive the second toe 215 and the fourth toe 217 to move inward, thereby closing the bionic webbed foot 218 between the toes to reduce the disturbance and resistance when leaving the ground.

[0093] Preferably, when the posture sensing system 3 detects that the ground elevation h is gradually decreasing, the controller controls the simulated flexor tendon drive motor 223 to drive the simulated flexor tendon 213 to contract, and controls the simulated extensor tendon drive motor 222 to reverse by the same angle, so that the webbed opening and closing angle θ gradually increases. At this time, the relationship between the webbed opening and closing angle θ and the ground elevation h sensed by the posture sensing system 3 is:

[0094]

[0095] Among them, θ is the opening and closing angle of the web;

[0096] h is the ground elevation perceived by the posture perception system 3;

[0097] k is the inverse coefficient;

[0098] r is the walking wheel radius;

[0099] l0 is the distance from the toe connection of the simulated flexor tendon to the base;

[0100] θ0 is the initial angle between the second or fourth toe and the extensor tendon;

[0101] When the posture sensing system 3 detects that the ground elevation h is no longer reduced, that is, it touches the ground, the controller controls the flexor tendon driving motor 223 to stop rotating. At this time, the toe web opening and closing angle is recorded as θ1. Until the walking wheel leg-foot monomer 2 leaves the ground or the ground elevation h increases, the controller controls the extensor tendon driving motor 222 to drive the extensor tendon to contract, and controls the flexor tendon driving motor 223 to reverse by the same angle. At this time, the relationship between the toe web opening and closing angle θ and the ground elevation h sensed by the posture sensing system 3 is:

[0102]

[0103] In a preferred embodiment of the present invention, the inverse coefficient k is mainly affected by the wheel foot contact area and the ground state, and the corresponding inverse coefficient can be formulated in combination with different conditions; the principle of value selection is preferred, in order to ensure that the walking wheel reaches the required traction force or traction efficiency and other indicators under the operating condition, the maximum sinking value is measured through actual tests, and the toe web opening and closing angle at this time is determined in combination with the maximum area of ​​the walking wheel contacting the ground, and then the specific value of the inverse coefficient k is determined. The toe web opening and closing angle is in direct proportion to the inverse coefficient. If it is found in the actual implementation process that the walking wheel sinks too much and the traction efficiency is low, the inverse coefficient can be adjusted to increase the toe web opening and closing angle, thereby increasing the walking wheel contact area, reducing the sinking amount, and improving the walking wheel performance; if it is found in the actual implementation process that the toe web opening and closing angle of the walking wheel is too large, resulting in energy waste, the inverse coefficient can be adjusted to reduce the toe web opening and closing angle, thereby improving the economic efficiency of the walking wheel. Therefore, the reasonable value of the inverse coefficient should be determined based on the actual situation. Different inverse coefficient values ​​should be used for different walking wheel foot areas and different ground conditions to achieve the maximum traction efficiency of the walking wheel.

[0104] In the present invention, when the walking wheel leg-foot monomer 2 touches the ground, the actual elevation of the walking wheel is monitored to decrease. At this time, the bionic tendon driving mechanism 22 will pull the toe web to open, thereby increasing the ground contact area and reducing the amount of sinking; conversely, when the actual elevation of the walking wheel is monitored to begin to increase, it means that the walking wheel leg-foot monomer 2 begins to leave the ground. At this time, the bionic tendon driving mechanism 22 will pull the toe web to close, thereby reducing the adhesion force off the ground and the disturbance to the ground, and producing an energy-saving effect; when swinging, the second toe 215 and the fourth toe 217 are completely closed under the action of the bionic tendon driving mechanism 22, achieving the closure of the web and reducing the resistance of the foot when moving forward in water and air. The walking wheel leg-foot monomer alternately contacts the ground, thereby achieving the rolling forward of the walking wheel.

[0105] It should be understood that although this specification is described according to various embodiments, not every embodiment contains only one independent technical solution. This narrative method of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation methods that can be understood by those skilled in the art.

[0106] The series of detailed descriptions listed above are only specific descriptions of feasible embodiments of the present invention. They are not intended to limit the scope of protection of the present invention. All equivalent embodiments or changes that do not deviate from the technical spirit of the present invention should be included in the scope of protection of the present invention.

Claims

1. A bionic adaptive anti-sinking walking wheel, characterized in that: It comprises a walking wheel flange (1), a walking wheel leg and foot unit (2), a position and posture sensing system (3) and a controller; The walking wheel flange (1) is provided with a plurality of walking wheel leg units (2) along the circumferential direction; The walking wheel leg-foot monomer (2) comprises a bionic tendon-bone coordination mechanism (21) and a bionic tendon driving mechanism (22); the bionic tendon driving mechanism (22) is arranged on the bionic tendon-bone coordination mechanism (21), and the bionic tendon driving mechanism (22) can open and close the bionic tendon-bone coordination mechanism (21); The position and posture sensing system (3) is installed on the walking wheel flange (1) and is used to detect the elevation signal from the walking wheel flange (1) to the ground and transmit it to the controller; The controller is connected to the posture sensing system (3) and the bionic tendon driving mechanism (22) respectively. The controller compares the ground elevation signal with a preset value and controls the bionic tendon driving mechanism (22) to open and close the bionic tendon-bone coordination mechanism (21) according to the comparison result.

2. The bionic adaptive anti-sinking walking wheel according to claim 1, characterized in that: The bionic tendon-bone coordination mechanism (21) comprises a bionic tarsometatarsal bone (211), a bionic extensor tendon (212), a bionic flexor tendon (213), a bearing support (214), a bionic second toe (215), a bionic third toe (216), a bionic fourth toe (217), a bionic fin (218) and a base (219); The bearing support (214) is arranged on the base (219), the simulated tarsometatarsus (211) is sleeved on the bearing support (214), the simulated flexor tendon (213) is divided into left and right ends below, one end of the simulated flexor tendon (213) is connected to the simulated second toe (215), the other end of the simulated flexor tendon (213) is connected to the simulated fourth toe (217), the upper part of the simulated flexor tendon (213) is connected to the rear side of the simulated tarsometatarsus (211); the simulated extensor tendon (212) is divided into left and right ends below, one end of the simulated extensor tendon (212) is connected to the simulated second toe (215), the other end of the simulated extensor tendon (212) is connected to the simulated fourth toe (217), the simulated extensor tendon (212) is connected to the simulated fourth toe (217), and the simulated extensor tendon (212) is connected to the simulated fourth toe (217). The upper part of the tendon (212) is connected to the front side of the simulated tarsometatarsal bone (211); the simulated second toe (215), the simulated fourth toe (217), and the simulated third toe (216) are respectively connected to the base (219), and the simulated second toe (215) and the simulated fourth toe (217) are respectively located on both sides of the simulated third toe (216); the bionic fin (218) is located at the bottom of the simulated second toe (215), the simulated fourth toe (217), and the simulated third toe (216); the middle part of the bionic fin (218) is connected to the simulated third toe (216), and the two sides of the bionic fin (218) are respectively connected to the simulated second toe (215) and the simulated fourth toe (217).

3. The bionic adaptive anti-sinking walking wheel according to claim 2, characterized in that: The bionic tendon driving mechanism (22) comprises a bionic extensor tendon driving motor (222) and a bionic flexor tendon driving motor (223); the bionic extensor tendon driving motor (222) is installed on the front side of the bionic tarsometatarsal bone (211); the power output shaft of the bionic extensor tendon driving motor (222) is connected to the bionic extensor tendon (212) and is used to pull the bionic extensor tendon (212) to drive the second toe (215) and the fourth toe (217) as well as the bionic webbed foot (218) between the toes to close; The flexor tendon-mimicking driving motor (223) is installed on the rear side of the tarsometatarsal bone (211), and the power output shaft of the flexor tendon-mimicking driving motor (223) is connected to the flexor tendon-mimicking driving motor (213) and is used to pull the flexor tendon-mimicking driving motor (213) to drive the second toe (215), the fourth toe (217) and the bionic webbed foot (218) between the toes to open; The controller is connected to the extensor tendon driving motor (222) and the flexor tendon driving motor (223) respectively; the controller compares the height signal of the posture sensing system (3) with a preset value, and issues instructions according to the comparison result to control the extensor tendon driving motor (222) and the flexor tendon driving motor (223) to perform corresponding actions, so as to open and close the bionic tendon-bone coordination mechanism (21).

4. The bionic adaptive anti-sinking walking wheel according to claim 3 is characterized in that: When the walking wheel leg-foot monomer (2) touches the ground, the height of the walking wheel flange (1) to the ground monitored by the posture sensing system (3) is lower than a preset value, and the controller controls the extensor tendon driving motor (222) to rotate in the reverse direction, so that the extensor tendon (212) is released, and controls the flexor tendon driving motor (223) to rotate in the forward direction, pulling the flexor tendon (213) to drive the second toe (215) and the fourth toe (217) to move outward, thereby opening the bionic webbed foot (218) between the toes; When the walking wheel leg-foot unit (2) starts to leave the ground, the height from the walking wheel flange (1) to the ground monitored by the posture sensing system (3) is higher than a preset value, and the controller controls the flexor tendon driving motor (223) to rotate in the reverse direction, so that the flexor tendon (213) is released, and controls the extensor tendon driving motor (222) to rotate in the forward direction, pulling the extensor tendon (212) to drive the second toe (215) and the fourth toe (217) to move inward, thereby closing the bionic webbed foot (218) between the toes to reduce the disturbance and resistance of leaving the ground.

5. The bionic adaptive anti-sinking walking wheel according to claim 1, characterized in that: The posture perception system (3) is a distance measuring sensor.

6. The bionic adaptive anti-sinking walking wheel according to claim 2, characterized in that: The simulated extensor tendon (212) is a fiber braided structure, including a fiber rope structure (2124), a flexible telescopic structure (2125) and a shell (2127); The fiber rope structure (2124) comprises a plurality of bundles of fibers (2121) arranged in a longitudinal spiral and fibers (2122) arranged in a transverse direction, wherein the fibers (2121) arranged in a longitudinal spiral and the fibers (2122) arranged in a transverse direction are interlaced and woven into the fiber rope structure (2124); The flexible telescopic structure (2125) comprises a plurality of springs (2123), and the plurality of springs (2123) are arranged to form the flexible telescopic structure (2125); The fiber rope structure (2124) and the flexible telescopic structure (2125) are longitudinally arranged and connected to form a bionic tendon unit (2126); a plurality of bionic tendon units (2126) are longitudinally arranged and wrapped with a nylon shell (2127) to form an extensor tendon (212); the extensor tendon (212) and the flexor tendon (213) have the same structure.

7. The bionic adaptive anti-sinking walking wheel according to claim 2, characterized in that: A first limiting mechanism (2141) and a second limiting mechanism (2142) are respectively provided on both sides of the bearing support (214); the first limiting mechanism (2141) is higher than the second limiting mechanism (2142); the first limiting mechanism (2141) is used to limit the minimum angle between the simulated tarsometatarsal bone (211) and the simulated third toe (216); and the second limiting mechanism (2142) is used to limit the maximum angle between the simulated tarsometatarsal bone (211) and the simulated third toe (216).

8. The bionic adaptive anti-sinking walking wheel according to claim 2, characterized in that: The base (219) is provided with a first slide groove (2191) and a second slide groove (2192); the first slide groove (2191) is distributed on one side of the second toe (215), and the second slide groove (2192) is distributed on one side of the fourth toe (217); the first slide groove (2191) and the second slide groove (2192) are symmetrically distributed along the axis of the simulated tarsometatarsus (211); one side of the starting end of the simulated flexor tendon (213) bypasses the first slide groove (2191), and the other side of the starting end of the simulated flexor tendon (213) bypasses the second slide groove (2192), and then merges and bypasses the simulated flexor tendon reserved hole (2161) set on the simulated third toe (216), and is connected to the rear side of the simulated tarsometatarsus (211) above.

9. A control method for a bionic adaptive anti-sinking walking wheel according to any one of claims 1 to 8, characterized in that: The following steps are involved: The posture sensing system (3) monitors the height h signal from the walking wheel flange (1) to the ground and transmits it to the controller; The controller compares the elevation h signal with a preset value, and controls the bionic tendon driving mechanism (22) to open and close the bionic tendon-bone coordination mechanism (21) according to the comparison result; When the walking wheel leg-foot monomer (2) touches the ground, and the height h from the walking wheel flange (1) to the ground monitored by the posture sensing system (3) is lower than a preset value, the controller controls the extensor tendon driving motor (222) to rotate in the reverse direction, so that the extensor tendon (212) is released, and controls the flexor tendon driving motor (223) to rotate in the forward direction, pulling the flexor tendon (213) to drive the second toe (215) and the fourth toe (217) to move outward, thereby opening the bionic webbed foot (218) between the toes; When the walking wheel leg-foot unit (2) leaves the ground, and the height h from the walking wheel flange (1) to the ground monitored by the posture sensing system (3) is higher than a preset value, the controller controls the flexor tendon driving motor (223) to rotate in the reverse direction, so that the flexor tendon (213) is released, and controls the extensor tendon driving motor (222) to rotate in the forward direction, pulling the extensor tendon (212) to drive the second toe (215) and the fourth toe (217) to move inward, thereby closing the bionic webbed foot (218) between the toes.

10. The control method of the bionic adaptive anti-sinking walking wheel according to claim 9, characterized in that: When the posture sensing system (3) detects that the ground elevation h is gradually decreasing, the controller controls the flexor tendon driving motor (223) to drive the flexor tendon (213) to contract, and controls the extensor tendon driving motor (222) to reverse by the same angle, so that the webbed opening and closing angle θ gradually increases. At this time, the relationship between the webbed opening and closing angle θ and the ground elevation h sensed by the posture sensing system (3) is: Among them, θ is the opening and closing angle of the web; h is the ground elevation perceived by the posture perception system (3); k is the inverse coefficient; r is the walking wheel radius; l0 is the distance from the toe connection of the simulated flexor tendon to the base; θ0 is the initial angle between the second or fourth toe and the extensor tendon; When the posture sensing system (3) detects that the ground elevation h is no longer decreasing, the controller controls the flexor tendon driving motor (223) to stop rotating. At this time, the toe web opening and closing angle is recorded as θ1. Until the walking wheel leg-foot monomer (2) leaves the ground or the ground elevation h increases, the controller controls the extensor tendon driving motor (222) to drive the extensor tendon to contract, and controls the flexor tendon driving motor (223) to reverse by the same angle. At this time, the relationship between the toe web opening and closing angle θ and the ground elevation h sensed by the posture sensing system (3) is:

Images