CN112590961B

CN112590961B - Bionic jumping leg adopting pneumatic series elastic joints

Info

Publication number: CN112590961B
Application number: CN202011550122.XA
Authority: CN
Inventors: 雷静桃; 沈双; 张悦文; 苏红升
Original assignee: University of Shanghai for Science and Technology
Current assignee: University of Shanghai for Science and Technology
Priority date: 2020-12-24
Filing date: 2020-12-24
Publication date: 2022-08-05
Anticipated expiration: 2040-12-24
Also published as: CN112590961A

Abstract

The invention discloses a bionic jumping leg adopting pneumatic series elastic joints, which consists of a hip joint module, a knee joint module and a pneumatic series elastic ankle joint module, which are sequentially connected from top to bottom, and 3 active joints are driven by 4 pneumatic artificial muscles; wherein: the hip joint module adopts 2 pneumatic artificial muscles to form antagonistic driving, and the length of a driving force arm and the joint rotation range are adjusted through a hip joint muscle force arm adjusting mechanism; the knee joint module consists of 1 pneumatic artificial muscle and 1 return spring; the ankle joint module adopts 1 pneumatic artificial muscle and high-rigidity elastic elements which are connected in series to form a pneumatic series elastic joint. The bionic jumping leg has the advantages of compact structure, impact resistance, elastic energy storage, light weight, miniaturization and the like, and can effectively improve the jumping performance of the bionic jumping leg.

Description

Bionic jumping leg adopting pneumatic series elastic joints

Technical Field

The invention belongs to the field of bionic robots, and particularly relates to a bionic jumping leg adopting pneumatic series elastic joints.

Background

The research of the bionic robot is developed from low speed to high speed, wherein the bionic jumping robot obtains the attention of numerous scholars by virtue of excellent complex terrain adaptability, and gradually develops towards the direction of light weight and miniaturization so as to obtain better jumping performance.

At present, the bionic leg type robot developed at home and abroad mostly adopts driving modes such as a motor, a hydraulic cylinder, a cylinder, pneumatic artificial muscles and the like. The driving modes such as motor and hydraulic pressure are difficult to apply to the light and small bionic jumping robot due to the disadvantages of the size and the weight, and the pneumatic artificial muscle is gradually applied to the bionic jumping robot due to the advantages of the flexibility, the high power density and the like.

The jumping motion of the leg type bionic jumping robot belongs to discrete single-point pavement support and has the characteristic of bionic discrete motion. In order to improve the mobility and flexibility of the discrete motion of the robot, the joints of the robot are required to have the characteristics of high driving torque, high driving speed and the like. The existing bionic leg type jumping robot motion joint is difficult to output larger peak power, lacks an effective landing energy storage structure and is difficult to obtain good jumping performance.

An elastic mechanism is designed between the joint of the bionic leg and the driving element, so that the output characteristic of the motion joint can be effectively improved, and the energy utilization efficiency is improved. The invention connects the driving element and the elastic element in series to form a series elastic driving joint, which can effectively store energy and amplify the peak output capability of the driver, thereby improving the performance of the jumping robot.

Disclosure of Invention

Aiming at the defects of the prior art, the invention relates to a bionic jumping leg adopting a pneumatic series elastic joint, and the bionic jumping leg has the advantages of compact structure, impact resistance, elastic energy storage, light weight, miniaturization and the like.

The technical scheme adopted by the invention is as follows:

a bionic jumping leg adopting pneumatic series elastic joints is composed of a hip joint module, a knee joint module and a pneumatic series elastic ankle joint module, wherein the hip joint module, the knee joint module and the pneumatic series elastic ankle joint module are sequentially hinged from top to bottom, 3 driving joints are driven to rotate by 4 pneumatic artificial muscles, and angular displacement sensors are respectively arranged at the 3 driving joints.

Preferably, the hip joint module consists of a lower body support, an upper femur support, hip joint extension muscles, hip joint contraction muscles and a hip joint angular displacement sensor; the hip joint extension muscle and the hip joint contraction muscle form antagonistic drive, and the length of the force arm of the hip joint extension muscle and the hip joint contraction muscle can be adjusted through the hip joint muscle force arm adjusting mechanism, so that the hip joint is driven to rotate.

Preferably, the knee joint module consists of a femur lower support, a tibia upper support, knee joint stretching muscles, knee joint return springs, knee joint pulleys and a knee joint angular displacement sensor, and is driven by 1 pneumatic artificial muscle, and the 1 return springs are reset.

Preferably, the pneumatic series Elastic ankle joint module consists of a tibia lower support, a metatarsus upper support, a foot end support, an ankle joint SEA (series Elastic activator) muscle, an ankle joint spring, an ankle joint return spring, an ankle joint pulley, an ankle joint angular displacement sensor, an ankle joint pulley angular displacement sensor and a bionic jumping leg and shank carbon tube, wherein the ankle joint pneumatic artificial muscle is connected with the ankle joint spring by bypassing the ankle joint pulley through a steel wire rope to form a series Elastic driver to drive the ankle joint to extend; the sole consists of a sole end bracket, a metatarsal upper bracket and two sole carbon tubes, the two sole carbon tubes are arranged in parallel to form the sole, and one side of the sole is provided with an ankle joint spring; the contraction quantity and the output force of an ankle joint spring in the series elastic ankle joint can be indirectly obtained through an ankle joint pulley angular displacement sensor; the pneumatic artificial muscle of the ankle joint is connected with the profile of the carbon tube of the bionic jumping leg shank through a muscle sliding block so as to ensure that the pneumatic artificial muscle is only stressed by axial force and not by bending moment when being inflated and contracted, and the contact surface of the muscle sliding block is coated with a lubricating coating.

Preferably, the hip joint module comprises a lower body support, an upper femur support, a bionic jumping leg trunk carbon tube, hip joint stretching muscles, hip joint contraction muscles and a hip joint angular displacement sensor; the hip joint stretching muscles and the hip joint contracting muscles form antagonistic driving, and the length of the force arms of the hip joint stretching muscles and the hip joint contracting muscles is adjusted through a hip joint muscle force arm adjusting mechanism so as to drive the hip joint to stretch and contract; the hip joint stretching muscle and the hip joint contracting muscle are respectively connected with the carbon tube profile of the bionic jumping leg trunk through a muscle sliding block so as to ensure that the pneumatic artificial muscle is only subjected to axial force and not bending moment during inflation and contraction, and a lubricating coating is coated on the contact surface of the muscle sliding block.

Preferably, the hip joint muscle force arm adjusting mechanism comprises a hip joint main pulley, a main pulley shaft, a hip joint auxiliary pulley, an auxiliary pulley shaft and two auxiliary pulley side plates. The hip joint main pulley shaft is arranged at the hip joint rotating shaft, and the auxiliary pulley side plate and the main pulley are respectively connected with the hip joint main pulley shaft through sliding bearings. The auxiliary pulley side plate is in a fan shape with a round angle, a plurality of holes are arranged at the arc end, and the centers of the plurality of holes and the center of the fan shape form an arithmetic progression. The auxiliary pulley shaft is parallel to the main pulley shaft and is arranged in a hole at the arc end of the side plate of the auxiliary pulley; the distance between the auxiliary pulley shaft and the hip joint rotating shaft can be adjusted by selecting different auxiliary pulley side plate holes. The hip joint auxiliary pulley is arranged in the middle of the auxiliary pulley shaft. Preferably, hip joint extension motion ranges determined by hip joint main pulleys with different radiuses correspond to hip joint contraction motion ranges determined by selecting different secondary pulley side plate mounting holes in a one-to-one mode.

Preferably, the knee joint module comprises a femur lower support, a tibia upper support, a bionic jumping leg thigh carbon tube, knee joint stretching muscles, knee joint return springs, knee joint pulleys and a knee joint angular displacement sensor, and is driven by 1 pneumatic artificial muscle, and the 1 return springs are reset; the knee joint stretching muscle is connected with the bionic jumping leg thigh carbon tube profile through a muscle sliding block so as to ensure that the knee joint stretching muscle is only stressed by axial force but not by bending moment when inflated and contracted, and a lubricating coating is coated on the contact surface of the muscle sliding block.

Preferably, the pneumatic series elastic joint consists of a shank connecting rod, a sole connecting rod, a joint moment arm pulley, a series elastic driver and a return spring; the series elastic driver is formed by connecting pneumatic artificial muscles and elastic elements in series; the pneumatic artificial muscle is arranged at the position of the shank connecting rod, the elastic element is arranged at the position of the sole connecting rod and is connected with the sole connecting rod by a steel wire rope bypassing the joint moment arm pulley; the joint moment arm pulley is hinged with the sole connecting rod, so that free rotation can be realized; the structure can shorten the length of the connecting rod of the ankle joint shank and increase the length of the pneumatic artificial muscle so as to ensure that the pneumatic artificial muscle has larger contraction quantity.

Preferably, the pneumatic series elastic ankle joint module is a spring with higher rigidity, so that the landing energy storage capacity of the pneumatic series elastic joint is improved; the rigidity of the knee joint return spring and the ankle joint return spring is low so as to reduce the weakening effect of the knee joint return spring and the ankle joint return spring on the maximum effective driving moment of the joint.

Preferably, the skeleton structure of the bionic jumping leg adopts a light hollow rod piece, and is fixedly connected with the resin support, so that the bionic jumping leg is light and small in weight on the premise of ensuring the structural strength, and the joint of the resin support is provided with an axial slot and is in interference fit with the skeleton light hollow rod piece through bolt connection. The hip joint, the knee joint and the ankle joint are provided with minimum limit structures at the resin support structures.

Preferably, one end of the pneumatic artificial muscle is hinged with the mechanism skeleton support through a muscle connector, and the other end of the pneumatic artificial muscle is connected with a steel wire rope through the muscle connector and is connected with the other mechanism skeleton support through a pulley.

Preferably, the hip joint main pulley, the knee joint pulley and the ankle joint pulley have various radius specifications, and the adjustment requirement of the rotation range of each joint can be met. The pulley radius is inversely proportional to the range of joint rotation without changing the initial length of the muscle.

Preferably, the 4 pneumatic artificial muscles are provided with muscle sliders and are connected with the molded surfaces of the light hollow rod pieces of the bionic jumping leg skeleton, the contact surfaces of the muscle sliders are coated with lubricating coatings and slide on the carbon tubes of the skeleton, and the pneumatic artificial muscles can be guaranteed to be only stressed by axial force and not under the action of bending moment during inflation and contraction.

The hip joint, the knee joint and the ankle joint are provided with minimum limit structures on resin supports.

Compared with the prior art, the invention has the following obvious prominent substantive characteristics and obvious technical progress:

1. the rigidity, the joint rotation angle, the joint driving torque and the like of each joint can be adjusted by selecting different mounting holes on the side plates of the pulleys with different radius specifications and the hip joint auxiliary pulley, so that the contradiction of large output force and short contraction stroke of pneumatic artificial muscle is avoided, and the jumping performance of different requirements is adapted;

2. the ankle joint adopts a series elastic joint structure, and adopts pneumatic artificial muscles to be connected with a high-rigidity elastic element in series to form a linear displacement type pneumatic series elastic driver (SEA), so that the bionic jumping leg has good flexibility and impact resistance, and obtains excellent jumping performance according to the characteristic of amplifying peak output power of a series elastic device;

3. the driving moment of hip joint contraction and reduction is large, active pneumatic artificial muscle is adopted to replace a passive return spring, and the weakening effect of a joint reduction structure on the peak driving moment of the hip joint is effectively avoided;

4. the bionic leg skeleton structure adopts a mode that a hollow rod piece structure is fixedly connected with a resin support, so that the light weight and the miniaturization of the bionic jumping leg are realized to the maximum extent while the structural strength is ensured.

Drawings

FIG. 1 is a schematic view of the overall structure of a bionic jumping leg with pneumatic series elastic joints according to the present invention

FIG. 2 is an exploded view of the hip joint structure of a bionic jumping leg using pneumatic tandem elastic joints according to the present invention

FIG. 3 is a schematic structural diagram of a hip joint muscle arm adjusting mechanism of a bionic jumping leg adopting pneumatic series elastic joints.

FIG. 4 is an exploded view of the knee joint structure of a bionic jumping leg using pneumatic tandem elastic joints according to the present invention

FIG. 5.a is a schematic diagram of the structure of the bionic jumping leg linear displacement type pneumatic series elastic joint of the present invention

FIG. 5.b is a schematic diagram of the structure of the series elastic joint after the bionic jumping leg is optimized

FIG. 6 is an exploded view of a series elastic ankle joint structure of a bionic jumping leg according to the present invention

Detailed Description

The invention will be further described with reference to preferred embodiments and the accompanying drawings, but the following embodiments are only illustrative and the scope of protection of the invention is not limited by these embodiments:

the first embodiment is as follows:

referring to fig. 1 to 6, a bionic jumping leg using pneumatic series elastic joints is composed of a hip joint module I, a knee joint module II, and a pneumatic series elastic ankle joint module III, and is characterized in that: the hip joint module I, the knee joint module II and the pneumatic series elastic ankle joint module III are sequentially hinged from top to bottom, wherein 4 pneumatic

artificial muscles

11, 17, 36, 66 or 52 are used for driving 3 joints to rotate, and angular displacement sensors are respectively arranged at 3 active joints.

The bionic jumping leg with the pneumatic series elastic joint has the advantages of compact structure, impact resistance, elastic energy storage, light weight, miniaturization and the like.

Example two:

this embodiment is substantially the same as the first embodiment, and is characterized in that:

the pneumatic series elastic ankle joint module III comprises a tibia lower support 56, a metatarsus upper support 58, a foot end support 63, an ankle joint pneumatic artificial muscle 66, an ankle joint spring 60, an ankle joint return spring 64, an ankle joint pulley 54, an ankle joint angular displacement sensor 57, an ankle joint pulley angular displacement sensor 70 and a bionic jumping leg and shank carbon tube 67, wherein the ankle joint pneumatic artificial muscle 66 bypasses the ankle joint pulley 54 through a steel wire rope 53 and is connected with the ankle joint spring 60 to form a series elastic driver to drive the ankle joint to move in a stretching mode; the sole comprises a sole end bracket 63, a metatarsal upper bracket 58 and two

sole carbon tubes

61 and 62, the two

sole carbon tubes

61 and 62 are arranged in parallel to form the sole, and one side of the sole is provided with an ankle joint spring 60; the contraction amount and the output force of the ankle spring 60 in the series elastic ankle joint can be indirectly obtained through the ankle pulley angular displacement sensor 70; the pneumatic artificial muscle 66 of the ankle joint is connected with the profile of the bionic jumping leg and shank carbon tube 67 through a muscle slider 68 so as to ensure that the pneumatic artificial muscle is only stressed by axial force and not by bending moment when being inflated and contracted, and the contact surface of the muscle slider 68 is coated with a lubricating coating.

The hip joint module I comprises a lower body support 2, an upper femur support 6, a bionic jumping leg trunk carbon tube 12, hip joint stretching muscles 17, hip joint contraction muscles 11 and a hip joint angular displacement sensor 1; the hip joint stretching muscle 17 and the hip joint contracting muscle 11 form antagonistic driving, the length of the force arm of the hip joint stretching muscle and the hip joint contracting muscle is adjusted through a hip joint muscle force arm adjusting mechanism, and then the hip joint stretching and contracting movement is driven; the hip joint extension muscle 17 and the hip joint contraction muscle 11 are respectively connected with the profile of the bionic jumping leg trunk carbon tube 12 through a muscle sliding block 18 and a muscle sliding block 10 so as to ensure that the pneumatic artificial muscle is only subjected to axial force and not to bending moment during inflation and contraction, and the contact surfaces of the

muscle sliding blocks

10 and 18 are coated with lubricating coatings.

The hip joint muscle force arm adjusting mechanism comprises a hip joint main pulley 4, a main pulley shaft 5, a hip joint auxiliary pulley 23, an auxiliary pulley shaft 22 and two auxiliary

pulley side plates

20 and 21; the hip joint main pulley shaft 5 is arranged at the hip joint rotating shaft, and the auxiliary

pulley side plates

20 and 21 and the main pulley 4 are respectively connected with the hip joint main pulley shaft 5; the radius size of the hip joint main pulley 4 has various specifications, and the radius of the main pulley 4 is inversely proportional to the stretching and rotating range of the hip joint on the premise of not changing the initial length of the hip joint stretching muscle 17; the auxiliary

pulley side plates

20 and 21 are fan-shaped with round corners, a plurality of holes are arranged at the arc ends, and the distances between the centroids of the plurality of holes and the circle centers of the fan-shaped holes form an equal difference array; the auxiliary pulley shaft 22 is parallel to the main pulley shaft 5 and is arranged in holes at the arc ends of the auxiliary

pulley side plates

20 and 21; the distance between the auxiliary pulley shaft 22 and the hip joint rotating shaft can be adjusted by selecting different auxiliary pulley side plate holes; on the premise of not changing the initial length of hip joint contraction muscles 11, the hip joint contraction rotation range is inversely proportional to the distance between the mounting holes of the auxiliary

pulley side plates

20 and 21 and the hip joint rotation axis; preferably, the hip joint extension motion range determined by the hip joint main pulleys 4 with different radiuses is in one-to-one correspondence with the hip joint contraction motion range determined by selecting the mounting holes of the

side plates

20 and 21 of the auxiliary pulleys.

In the embodiment, the rigidity, the joint rotation angle, the joint driving torque and the like of each joint can be adjusted by selecting the pulleys with different radius specifications and different mounting holes on the side plates of the hip joint secondary pulley, so that the contradiction of large output force and short contraction stroke of the pneumatic artificial muscle is avoided, and the jumping performance of different requirements is adapted; the ankle joint of the embodiment adopts a series elastic joint structure, adopts pneumatic artificial muscles to be connected with a high-rigidity elastic element in series to form a linear displacement type pneumatic series elastic driver SEA, has good flexibility and impact resistance, and enables the bionic jumping leg to obtain excellent jumping performance according to the characteristic of amplifying peak output power of a series elastic device; the hip joint contraction resetting driving torque of the embodiment is larger, and the passive return spring is replaced by active pneumatic artificial muscle, so that the weakening effect of the joint resetting structure on the peak driving torque of the hip joint is effectively avoided; the bionic leg skeleton structure of the embodiment adopts a mode that a hollow rod piece structure is fixedly connected with a resin support, so that the light weight and the miniaturization of the bionic jumping leg are realized to the maximum extent while the structural strength is ensured.

Example three:

as shown in fig. 1, a bionic jumping leg using pneumatic series elastic joints comprises a hip joint module I, a knee joint module II, and a pneumatic series elastic ankle joint module III; the hip joint module I, the knee joint module II and the pneumatic series elastic ankle joint module III are sequentially hinged from top to bottom; the rotation axes of the hip joint, the knee joint and the ankle joint are parallel; the bionic jumping leg skeleton structure is characterized in that the skeleton structure of the bionic jumping leg is fixedly connected by a light hollow rod piece and a resin support, the bionic jumping leg is light and miniaturized while the structural strength is guaranteed, an axial slot is formed in the joint of the resin support and forms interference fit with the skeleton light hollow rod piece through bolt connection, and the hip joint, the knee joint and the ankle joint are all provided with minimum limit structures in the resin support structure.

As shown in fig. 2, the hip joint module I is composed of a lower body support 2, an upper femur support 6, a hip joint stretching muscle 17, a hip joint contracting muscle 11, muscle connectors 9, 13, 15, 19, muscle sliders 10, 18, steel wire ropes 3, 8 and a hip joint angular displacement sensor 1; the hip joint module I is formed by hip joint extension muscles 17 and hip joint contraction muscles 11 to form antagonistic drive, and the length of the force arm of the hip joint extension muscles and the hip joint contraction muscles can be adjusted through a hip joint muscle force arm adjusting mechanism so as to drive the hip joint to rotate; the hip joint stretching muscle 17 is connected with the upper body support 14 through a first muscle connector 15 and is connected with the upper femur support 6 through a second muscle connector 19 and a steel wire rope 3 which bypasses the hip joint main pulley 4; wherein the hip joint stretching muscle 17 is respectively connected with a first muscle connector 15 and a second muscle connector 19 by nuts, the first muscle connector 15 is connected with the upper bracket 14 of the body by a screw bolt, and the second muscle connector 19 is connected with the steel wire rope 3 by binding; the hip joint contraction muscle 11 is connected with the upper body support 14 through a third muscle connector 13 and is connected with the upper femur support 6 through a fourth muscle connector 9 and a steel wire rope 8 by bypassing the auxiliary hip joint pulley; wherein the hip joint contraction muscle 11 is respectively connected with a third muscle connector 13 and a fourth muscle connector 9 by nuts, the third muscle connector 13 is connected with the upper bracket 14 of the body by a screw bolt, and the fourth muscle connector 9 is connected with the steel wire rope 8 by binding; the upper body support 14 and the lower body support 2 are respectively connected by bolts to form interference fit with the body carbon tube 12, and the upper femur support 6 is connected by bolts to form interference fit with the thigh carbon tube 37; a hip joint movement limiting structure 7 is arranged at the upper femur bracket 6 to ensure that the minimum contraction angle of the hip joint is constant; the hip joint extension muscle 17 and the hip joint contraction muscle 11 are respectively connected with the profile of the trunk carbon tube 12 through muscle sliders 18 and 10, so that the hip joint extension muscle 17 and the hip joint contraction muscle 11 are only stressed by axial force and are not stressed by bending moment when inflated and contracted; wherein, the contact surface of the muscle sliding blocks 18 and 10 is coated with a lubricating coating; the hip joint angular displacement sensor 1 is used for detecting the rotation angle between the lower body support 2 and the upper femur support 6.

As shown in fig. 3, the hip joint muscle force arm adjusting mechanism comprises a hip joint main pulley 4, a main pulley shaft 5, a hip joint auxiliary pulley 23, an auxiliary pulley shaft 22 and two auxiliary pulley side plates 20 and 21; the hip joint main pulley shaft 5 is arranged at the hip joint rotating shaft, and the auxiliary pulley side plates 20 and 21 and the main pulley 4 are respectively connected with the hip joint main pulley shaft 5; the radius size of the hip joint main pulley 4 has various specifications, and the radius of the main pulley 4 is inversely proportional to the stretching and rotating range of the hip joint on the premise of not changing the initial length of the hip joint stretching muscle 17; the auxiliary pulley side plates 20 and 21 are fan-shaped with round corners, a plurality of holes are arranged at the arc ends, and the distances between the centroids of the plurality of holes and the circle centers of the fan-shaped holes form an equal difference array; the auxiliary pulley shaft 22 is parallel to the main pulley shaft 5 and is arranged in holes at the arc ends of the auxiliary pulley side plates 20 and 21; the distance between the auxiliary pulley shaft 22 and the hip joint rotating shaft can be adjusted by selecting different auxiliary pulley side plate holes; the hip joint auxiliary pulley 23 is arranged in the middle of the auxiliary pulley shaft 22 to ensure that the hip joint auxiliary pulley 23 is positioned in the center of the hip joint of the bionic jumping leg; on the premise of not changing the initial length of hip joint contraction muscles 11, the hip joint contraction rotation range is inversely proportional to the distance between the mounting holes of the auxiliary pulley side plates 20 and 21 and the hip joint rotation axis; preferably, the hip joint extension motion range determined by the hip joint main pulleys 4 with different radiuses is in one-to-one correspondence with the hip joint contraction motion range determined by selecting the mounting holes of the side plates 20 and 21 of the auxiliary pulleys.

As shown in fig. 4, the knee joint module II includes a femur lower support 33, a tibia upper support 28, a knee joint extension muscle 36, a knee joint return spring 25, a knee joint pulley 32, muscle connectors 34 and 38, a muscle slider 35, a steel wire rope 30, and a knee joint angular displacement sensor 29; the lower femoral support 33 is connected with the thigh carbon tube 37 by bolts to form interference fit, and the upper tibial support 28 is connected with the shank carbon tube 67 by bolts to form interference fit; the knee joint stretching muscle 36 is connected with the upper femoral support 6 through a fifth muscle connector 38 and is connected with the upper tibial support 28 through a sixth muscle connector 34 and a steel wire rope 30 by bypassing the knee joint pulley 32; the knee joint stretching muscle 36 is connected with the muscle connectors 34 and 38 through nuts, and the fifth muscle connector 38 is connected with the upper femoral support 6 through a stud; the radius of the knee joint pulley 32 has various specifications, and the radius of the pulley is inversely proportional to the extension rotation range of the knee joint on the premise of not changing the initial length of the knee joint extension muscle 36; a knee joint movement limiting structure 27 is arranged at the position of the tibia upper support 28 to ensure that the minimum contraction angle of the knee joint is constant; the knee joint stretching muscle 36 is connected with the molded surface of the thigh carbon tube 37 through the muscle sliding block 35 to ensure that the knee joint stretching muscle 36 is only stressed by axial force and not under the action of bending moment when being inflated and contracted; the upper end of the knee joint return spring 25 is connected to the upper femoral bracket 6 through a steel wire rope 24, and the lower end is connected to the upper tibial bracket 28 through a steel wire rope 26; the knee angular displacement sensor 29 is used to detect the rotation angle between the femoral lower mount 33 and the tibial upper mount 28.

As shown in fig. 5.a, the linear displacement pneumatic series elastic joint comprises a lower leg connecting rod 39, a sole connecting rod 41, a joint moment arm pulley 42, a series elastic driver 44 and a return spring 40; wherein, the series elastic driver 44 is formed by connecting a pneumatic artificial muscle 45 and an elastic element 43 in series; the joint moment arm pulley 42 is fixedly connected with the sole connecting rod 41, so that the moment arm of the driving force can be ensured to be constant in the joint movement process; two ends of the return spring 40 are connected with the upper end of the shank connecting rod 39 and the upper end of the sole connecting rod 41 through steel wires; in the optimized fig. 5.b, the pneumatic artificial muscle 52 is arranged at the position of the crus connecting rod 46, the elastic element 49 is arranged at the position of the sole connecting rod 48 and is connected by a steel wire rope 50 by winding around the joint moment arm pulley 51; the joint moment arm pulley 51 is hinged with the sole connecting rod 48, so that free rotation can be realized; the length of ankle joint shank link can be shortened to the structural arrangement mode after the optimization, increases pneumatic artificial muscle's initial length to guarantee that pneumatic artificial muscle has great contraction volume.

As shown in fig. 6, the pneumatic series elastic ankle joint module III comprises a tibia lower support 56, a metatarsus upper support 58, a foot end support 63, an ankle pneumatic artificial muscle 66, an ankle spring 60, an ankle restoring spring 64, an ankle pulley 54, muscle connectors 65 and 69, a muscle slider 68, a steel wire rope 53, an ankle angular displacement sensor 57 and an ankle pulley angular displacement sensor 70; the ankle pneumatic artificial muscle 66 bypasses the ankle pulley 54 through the steel wire rope 53 to be connected with the ankle spring 60 to form a series elastic driver to drive the ankle to stretch; the sole consists of a sole end bracket 63, a metatarsal upper bracket 58 and two sole carbon tubes 61 and 62, the two sole carbon tubes 61 and 62 are distributed at two sides of the sole, and an ankle joint spring 60 is arranged in a reserved space in the middle; the foot end bracket 63 and the metatarsal upper bracket 58 are respectively connected by bolts to form interference fit with the two sole carbon tubes 61 and 62, and the tibia upper bracket 28 and the tibia lower bracket 56 are respectively connected by bolts to form interference fit with the shank carbon tube 67; the radius of the ankle joint pulley 54 has various specifications, and the radius of the pulley is inversely proportional to the stretching and rotating range of the ankle joint on the premise of not changing the initial length of the pneumatic ankle joint artificial muscle 66 and the rigidity of the ankle joint spring 60; the upper end of the ankle joint restoring spring 64 is connected to the upper tibial bracket 28 through a steel wire rope, and the lower end is connected to the upper metatarsal bracket 58 through a steel wire rope; the pneumatic artificial ankle muscle 66 is connected with the profile of the shank carbon tube 67 through the muscle slider 68, so that the pneumatic artificial ankle muscle 66 is only stressed by axial force and is not stressed by bending moment when being inflated and contracted; an ankle angular displacement sensor 57 for detecting the rotational angle between the tibia lower support 56 and the metatarsal upper support 58, and an ankle pulley angular displacement sensor 70 for detecting the rotational angle between the metatarsal upper support 58 and the ankle pulley 54; an ankle joint movement limiting structure 59 is arranged at the metatarsal upper support 58 to ensure that the minimum contraction angle of the ankle joint is constant; the amount of contraction and output force of the ankle spring 60 in the series elastic ankle joint can be indirectly obtained by the ankle pulley angular displacement sensor 70.

The pneumatic series elastic ankle joint module III selects an ankle joint spring 60 with higher rigidity so as to improve the landing energy storage capacity of the pneumatic series elastic ankle joint; the knee return spring 25 and the ankle return spring 64 are of lesser stiffness to reduce their weakening of the maximum effective drive torque of the joint.

In summary, the bionic jumping leg adopting pneumatic series elastic joints in the above embodiment is composed of a hip joint module, a knee joint module and a pneumatic series elastic ankle joint module, which are sequentially connected from top to bottom, and 3 active joints are driven by 4 pneumatic artificial muscles; wherein: the hip joint module adopts 2 pneumatic artificial muscles to form antagonistic driving, and the length of a driving force arm and the joint rotation range are adjusted through a hip joint muscle force arm adjusting mechanism; the knee joint module consists of 1 pneumatic artificial muscle and 1 return spring; the ankle joint module adopts 1 pneumatic artificial muscle and high-rigidity elastic elements which are connected in series to form a pneumatic series elastic joint. The embodiment adopts the light hollow rod piece as the framework of the bionic jumping leg, has the advantages of compact structure, impact resistance, elastic energy storage, light weight, miniaturization and the like, and can effectively improve the jumping performance of the bionic jumping leg.

The embodiments of the present invention have been described above with reference to the accompanying drawings, but the present invention is not limited to the above embodiments, and various changes can be made according to the purpose of the invention, and any changes, modifications, substitutions, combinations or simplifications made according to the spirit and principle of the technical solution of the present invention should be replaced with equivalents as long as the object of the present invention is met, and the technical principle and the inventive concept of the present invention are not departed from the scope of the present invention.

Claims

1. The utility model provides an adopt bionical jump leg of pneumatic series connection elastic joint comprises hip joint module (I), knee joint module (II), pneumatic series connection elastic ankle joint module (III), its characterized in that: the hip joint module (I), the knee joint module (II) and the pneumatic series elastic ankle joint module (III) are sequentially hinged from top to bottom, 4 pneumatic artificial muscles (11, 17, 36, 66 or 52) are used for driving 3 joints to rotate, and angular displacement sensors are respectively arranged at 3 active joints;

the pneumatic series elastic ankle joint module (III) comprises a tibia lower support (56), a metatarsus upper support (58), a foot end support (63), an ankle pneumatic artificial muscle (66), an ankle spring (60), an ankle restoring spring (64), an ankle pulley (54), an ankle angular displacement sensor (57), an ankle pulley angular displacement sensor (70) and a bionic jumping leg lower leg carbon tube (67), wherein the ankle pneumatic artificial muscle (66) bypasses the ankle pulley (54) through a steel wire rope (53) to be connected with the ankle spring (60) to form a series elastic driver to drive the ankle to move in a stretching mode; the sole comprises a sole end bracket (63), a metatarsal upper bracket (58) and two sole carbon tubes (61, 62), the two sole carbon tubes (61, 62) are arranged in parallel to form the sole, and one side of the sole is provided with an ankle joint spring (60); the contraction quantity and the output force of an ankle joint spring (60) in the series elastic ankle joint can be indirectly obtained through an ankle joint pulley angular displacement sensor (70); the pneumatic artificial muscle (66) of the ankle joint is connected with the profile of the bionic jumping leg shank carbon tube (67) through a muscle sliding block (68) so as to ensure that the pneumatic artificial muscle is only stressed by axial force and not under the action of bending moment when inflated and contracted, and the contact surface of the muscle sliding block (68) is coated with a lubricating coating.

2. The bionic jumping leg adopting the pneumatic series elastic joint as claimed in claim 1, wherein the hip joint module (I) comprises a lower body support (2), an upper femur support (6), a bionic jumping leg trunk carbon tube (12), hip joint extension muscles (17), hip joint contraction muscles (11) and a hip joint angular displacement sensor (1); the hip joint stretching muscle (17) and the hip joint contraction muscle (11) form antagonistic driving, the length of the force arm of the hip joint stretching muscle and the hip joint contraction muscle is adjusted through a hip joint muscle force arm adjusting mechanism, and then the stretching and the contraction of the hip joint are driven; the hip joint extension muscle (17) and the hip joint contraction muscle (11) are respectively connected with the profile of the bionic jumping leg trunk carbon tube (12) through a muscle sliding block (18, 10) so as to ensure that the pneumatic artificial muscle is only stressed by axial force and not by bending moment when inflated and contracted, and the contact surface of the muscle sliding block (10, 18) is coated with a lubricating coating.

3. The bionic jumping leg adopting the pneumatic series elastic joint as claimed in claim 2, wherein the hip joint muscle arm adjusting mechanism comprises a hip joint main pulley (4), a main pulley shaft (5), a hip joint auxiliary pulley (23), an auxiliary pulley shaft (22) and two auxiliary pulley side plates (20, 21); the hip joint main pulley shaft (5) is arranged at the hip joint rotating shaft, and the auxiliary pulley side plates (20 and 21) and the main pulley (4) are respectively connected with the hip joint main pulley shaft (5); the radius size of the hip joint main pulley (4) has various specifications, and the radius of the main pulley (4) is inversely proportional to the stretching and rotating range of the hip joint on the premise of not changing the initial length of hip joint stretching muscles (17); the auxiliary pulley side plates (20 and 21) are in a fan shape with round corners, a plurality of holes are arranged at the arc ends, and the distances between the centroids of the plurality of holes and the circle centers of the fan shape form an equal difference array; the auxiliary pulley shaft (22) is parallel to the main pulley shaft (5) and is arranged in holes at the arc ends of the auxiliary pulley side plates (20 and 21); the distance between the auxiliary pulley shaft (22) and the hip joint rotating shaft can be adjusted by selecting different auxiliary pulley side plate holes; under the premise of not changing the initial length of hip joint contraction muscles (11), the hip joint contraction rotation range is inversely proportional to the distance between the mounting holes of the side plates (20 and 21) of the secondary pulleys and the hip joint rotation axis; the hip joint extension motion range determined by the hip joint main pulleys (4) with different radiuses is in one-to-one correspondence with the hip joint contraction motion range determined by selecting the mounting holes of the side plates (20, 21) of the auxiliary pulleys.

4. The bionic jumping leg adopting the pneumatic series elastic joint as claimed in claim 1, wherein the knee joint module (II) comprises a femur lower support (33), a tibia upper support (28), a bionic jumping leg thigh carbon tube (37), knee joint extension muscles (36), knee joint return springs (25), knee joint pulleys (32) and a knee joint angular displacement sensor (29), is driven by 1 pneumatic artificial muscle (36), and 1 return spring (25) is reset; the knee joint stretching muscle (36) is connected with the molded surface of the bionic jumping leg thigh carbon tube (37) through a muscle sliding block (35) so as to ensure that the knee joint stretching muscle is only acted by axial force but not bending moment when being inflated and contracted, and the contact surface of the muscle sliding block (35) is coated with a lubricating coating.

5. The bionic jumping leg adopting the pneumatic series elastic joint as claimed in claim 1, wherein the pneumatic series elastic ankle joint module (III) comprises a shank connecting rod (46), a sole connecting rod (48), a joint moment arm pulley (51), a series elastic driver (44) and a return spring (47); the series elastic driver (44) is formed by connecting a pneumatic artificial muscle (52) and an elastic element (49) in series; the pneumatic artificial muscle (52) is arranged at the position of a shank connecting rod (46), the elastic element (49) is arranged at the position of a sole connecting rod (48) and is connected by a steel wire rope (50) by winding around a joint moment arm pulley (51); the joint moment arm pulley (51) is hinged with the sole connecting rod (48) to realize free rotation; the structure arrangement mode structure can shorten the length of the connecting rod of the ankle joint shank and increase the initial length of the pneumatic artificial muscle so as to ensure that the pneumatic artificial muscle has larger contraction quantity.

6. The bionic jumping leg adopting the pneumatic series elastic joint as claimed in claim 1, wherein the skeleton structure of the bionic jumping leg adopts a light hollow rod and is fixedly connected with a resin support, so that the bionic jumping leg is light and miniaturized under the premise of ensuring the structural strength, the joint of the resin support is provided with an axial slot and is in interference fit with the light hollow rod of the skeleton through bolt connection, and the hip joint, the knee joint and the ankle joint are all provided with minimum limit structures at the resin support structure.