CN114392131A - A passive exoskeleton assisting device for hip and knee joint based on energy storage - Google Patents

Abstract

The invention discloses an energy storage-based passive exoskeleton assisting device for hip and knee joints, which belongs to the technical field of lower limb exoskeletons. The present invention provides a fixed installation platform for the thigh energy storage assembly and the calf energy storage assembly through the waist fixing assembly. The thigh energy storage assembly and the calf energy storage assembly respectively pass through the designed first elastic element and second elastic element. When swinging, the first elastic element is stretched, absorbs the negative work done when the thigh swings back, and recovers and releases energy in the early swing phase to provide an auxiliary torque for hip flexion; in the later swing phase, when the calf stretches forward, the second elastic element is pulled forward. Stretch, absorb the negative work done when the calf stretches forward, convert the negative work done when the calf stretches forward into elastic potential energy, and restore the hip joint extension auxiliary torque when the thigh swings back in the support phase. That is, during the entire gait cycle, the extension and flexion of the hip joint are assisted at the same time, which improves the assisting efficiency of the exoskeleton.

Description

A passive exoskeleton assisting device for hip and knee joint based on energy storage

technical field

The invention belongs to the technical field of lower extremity exoskeletons, and more particularly relates to an energy storage-based passive exoskeleton assisting device for hip and knee joints.

Background technique

Walking is one of the most common sports in people's daily life, and people take tens of thousands of steps every day on average. However, a lot of energy is consumed during walking. Although people optimize their walking strategies according to different road conditions to reduce energy consumption as much as possible, people's walking distance is often limited due to physical exhaustion. In addition, for some groups with movement difficulties or obstacles, such as heavy weight people, the elderly, and patients with lower extremity arthritis, the decline in walking efficiency has brought great obstacles to daily life. Therefore, exoskeletons that can reduce the metabolic energy consumption of walking have strong application value.

Existing exoskeleton devices can be divided into active exoskeleton devices and passive exoskeleton devices. Among them, active exoskeletons mostly use motors to assist the human body, and it is difficult to achieve the purpose of reducing metabolic energy due to their disadvantages such as heavy weight and poor flexibility. Passive exoskeletons improve the walking efficiency of users through the recovery and utilization of energy during the walking cycle, and do not require motor assistance, so the weight can be greatly reduced, and it is easy to wear, making it more suitable for use in daily life. Existing passive exoskeleton devices can only achieve assisted hip joint extension or flexion, but cannot achieve both assisted hip joint extension and flexion, and the exoskeleton assisting efficiency is limited. Moreover, the existing passive exoskeleton devices can only function in one or two periods of the stance phase, the stance phase, the swing phase, or the swing phase of the gait cycle, but not in the entire gait cycle. Can give exoskeleton help.

SUMMARY OF THE INVENTION

In view of the defects and improvement needs of the prior art, the present invention provides an energy storage-based passive exoskeleton assisting device for the hip and knee joint, the purpose of which is to simultaneously assist the extension and flexion of the hip joint during the entire gait cycle, and enhance the external Bone boost efficiency.

In order to achieve the above object, the present invention provides an energy storage-based passive exoskeleton assisting device for hip and knee joints, including: a waist fixing assembly, a thigh energy storage assembly and a calf energy storage assembly;

The waist fixing component is fixed on the waist of the user, and is used to provide a fixed installation platform for the thigh energy storage component and the calf energy storage component;

There are two groups of thigh energy storage assemblies, each group of thigh energy storage assemblies includes a first elastic element, a thigh drawstring and a thigh strap, and the two ends of the thigh drawstring are respectively connected to the first elastic element and the thigh. One end of the strap, the first elastic element and the other end of the thigh strap are respectively arranged on the front side of the waist fixing assembly and the thigh, and the first elastic element is stretched when the thigh is swayed back in the support phase , and the elastic potential energy of the first elastic element is not greater than the negative work done when the thigh swings back;

There are two sets of calf energy storage assemblies, each set of calf energy storage assemblies includes a second elastic element, a calf drawstring and a calf strap, and the two ends of the calf drawstring are respectively connected to the second elastic element and the calf. One end of the strap, the second elastic element and the other end of the calf strap are respectively arranged on the back side of the waist fixing assembly and on the calf, and the second elastic element is stretched when the calf stretches forward in the late swing phase , and the elastic potential energy of the second elastic element is not greater than the negative work done when the calf stretches forward.

Further, the value range of the stiffness K ₁ of the first elastic element is: 0<K ₁ ≤3.5kN/m; the value range of the stiffness K ₂ of the second elastic element is: 1.5≤K ₂ ≤ 4.0kN/m.

Further, the stiffness of the first elastic element is 2.3 kN/m, and the stiffness of the second elastic element is 3.0 kN/m.

Further, the first elastic element or the second elastic element is a tension spring or an elastic band.

Further, the waist fixing assembly includes an upper waist belt, a lower waist belt, a waist plate and a cantilever beam unit, the waist plate is divided into two symmetrical pieces and fixed at the back waist of the user respectively, and the upper waist belt and the lower waist belt pass through respectively. The waist plate is fixed on the upper abdomen and the lower abdomen of the user, and the cantilever beam unit is arranged on the waist plate and is elastically connected with the first elastic element and the second elastic element.

Further, the cantilever beam unit includes a horizontal cantilever beam, a horizontal cantilever beam fixing member arranged at both ends of the horizontal cantilever beam, two side suspension beams, a side suspension beam fixing member arranged at one end of the two side suspension beams, and two rear suspension beams, so The horizontal cantilever beam fixing piece and the side cantilever beam fixing piece are connected by snap-locking for fixedly connecting the horizontal cantilever beam and the two side cantilever beams; the other ends of the two side cantilever beams are connected to both sides of the waist plate. Fixed connection; one end of the two rear suspension beams is fixedly connected to the lower part of the waist plate, and the other end is elastically connected to the second elastic element respectively.

Further, the horizontal cantilever beam is provided with a plurality of installation holes, and one end of the first elastic element is elastically connected to the horizontal cantilever beam through the installation holes.

Further, the lengths of the thigh drawstring and the calf drawstring can be adjusted.

Further, the material of the thigh drawstring, the calf drawstring, the thigh strap and the calf strap is a flexible material, the material of the horizontal suspension beam and the two side suspension beams is a carbon fiber board, and the material of the waist plate is resin or nylon. glassfiber.

Further, the waist plate is provided with a reinforcing rib, and the reinforcing rib is arranged along the direction in which the waist plate is stressed.

In general, through the above technical solutions conceived by the present invention, the following beneficial effects can be achieved:

(1) The passive exoskeleton booster designed by the present invention provides a fixed installation platform for the thigh energy storage assembly and the calf energy storage assembly through the waist fixing assembly, and the thigh energy storage assembly and the calf energy storage assembly pass through the designed first elastic element and For the second elastic element, when the thigh is swayed backward in the support phase, the first elastic element is stretched, and the elastic potential energy of the elastic element is not greater than the negative work done when the thigh is swayed backwards, and can absorb the negative work done when the thigh is swayed backwards , and recover and release energy in the early swing phase to provide auxiliary torque for hip joint flexion; in the late swing phase, when the calf stretches forward, the second elastic element is stretched, and the elastic potential energy of the elastic element is not greater than the negative work done when the calf stretches forward. , absorb the negative work done when the calf stretches forward, the negative work done when the calf stretches forward is converted into elastic potential energy, and restores the hip joint extension auxiliary torque when the thigh swings back in the early support phase. That is to say, in the whole gait cycle, the extension and flexion of the hip joint can be assisted at the same time, the exoskeleton assisting efficiency is improved, the walking efficiency is improved, and the metabolic energy consumption of the human body and the force on the muscles of the lower limbs during walking can be effectively reduced.

(2) Preferably, when the first elastic element and the second elastic element satisfy a certain rigidity requirement range, when the first elastic element or the second elastic element is stretched, the elastic potential energy of the elastic element is not greater than the back swing of the thigh Or the negative work done when the calf stretches forward to meet the power assist requirements.

(3) Preferably, when the rigidity of the first elastic element is 2.3 kN/m and the rigidity of the second elastic element is 3.0 kN/m, the elastic potential energy of the first elastic element and the second elastic element are just the same as the backswing of the thigh, respectively. The negative work done by the thigh and the calf during the entire gait cycle is exactly the same as the negative work done when the calf extends forward, that is, the negative work done by the thigh and the calf is exactly converted into the elastic potential energy of the elastic element. At this time, the metabolic energy consumption of the human body is the lowest.

(4) In the passive exoskeleton power assist device of the present invention, the thigh straps, calf straps, thigh ropes and calf ropes are all flexible wearing methods, which can adapt to users of different sizes, and can avoid the rigidity of the exoskeleton. Movement restrictions due to poor coupling between the frame and the human body.

(5) In the passive exoskeleton power assist device of the present invention, the upper waist belt is tied to the upper abdomen of the user, which can prevent the waist plate from tilting backward when the rear suspension beam is stressed, and the lower waist belt is tied to the lower abdomen of the user, which can prevent the waist from being fixed. The components fall off when stressed, and the tightness can be adjusted according to the user's body shape.

(6) In the passive exoskeleton power assist device of the present invention, the reinforcing ribs provided on the waist plate can enhance the strength and bending resistance of the waist plate.

All in all, the present invention can simultaneously assist in the extension and flexion of the hip joint during the entire gait cycle, thereby improving the assisting efficiency of the exoskeleton. In addition, the device of the present invention is a pure passive exoskeleton assisting device, does not use electronic components such as motors and sensors, and has the advantages of light weight, high robustness, and convenient wearing.

Description of drawings

FIG. 1 is a schematic diagram of the overall structure of the passive exoskeleton assisting device for hip and knee joint based on energy storage provided by the present invention.

FIG. 2 is an enlarged schematic diagram of a partial structure of the passive exoskeleton assisting device for hip and knee joint based on energy storage provided by the present invention.

FIG. 3 is a schematic diagram of wearing a passive exoskeleton assisting device for hip and knee joint based on energy storage provided by the present invention.

FIG. 4 is a schematic diagram of the assistance of the exoskeleton assistance device of the present invention in the entire gait cycle.

Throughout the drawings, the same reference numbers are used to refer to the same elements or structures, wherein:

1- Upper waist belt, 2- Lower waist belt, 3- Side suspension beam, 4- First elastic element, 5- Thigh drawstring, 6- Thigh strap, 7- Calf strap, 8- Waist plate, 9- Rear suspension beam, 10 -Second elastic element, 11-calf drawstring, 12-transverse suspension beam, 13-transverse suspension beam fixing piece, 14-side suspension beam fixing piece.

Detailed ways

In order to make the objectives, technical solutions and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention, but not to limit the present invention. In addition, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

In the present invention, the terms "first", "second" and the like in the present invention and the accompanying drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence.

As shown in FIGS. 1-3 , an energy storage-based passive exoskeleton assisting device for hip and knee joints provided by the present invention includes three parts: a waist fixing assembly, a thigh energy storage assembly, and a calf energy storage assembly. Wherein, the waist fixing component is fixed on the waist of the user, and is used to provide a fixed installation platform for the thigh energy storage component and the calf energy storage component.

The thigh energy storage component is provided with two groups and is symmetrically arranged on the front side of the user's waist fixing component and the thigh (the component end is connected to the front side of the waist fixing component, and the other end is fixed on the thigh), and is used for extending the hip joint. The negative work is converted into a hip flexion assist moment. Specifically, in the later stage of the support phase, the first elastic element 4 provided in the assembly is stretched when the thigh is swayed back, and the elastic potential energy of the elastic element is not greater than the negative work performed when the thigh is swayed back, so that the thigh can be swung back. The negative work done by the extension of the hip joint is converted into the elastic potential energy of the first elastic element, and the first elastic element recovers and releases the elastic potential energy when the calf stretches forward in the early swing phase, so as to provide an auxiliary moment for flexion of the hip joint. Specifically, when the value range of the stiffness K ₁ of the first elastic element 4 is: 0<K ₁ ≤3.5kN/m, it is satisfied that the elastic potential energy of the elastic element is not greater than the negative work done when the thigh swings back, and the support is realized. The assistance requirements when the thighs are swayed back.

The calf energy storage assembly is provided with two groups and is symmetrically arranged on the back side of the user's waist fixing assembly and the calf (one end of the assembly is connected to the rear side of the waist fixing assembly, and the other end is fixed on the calf). The calf energy storage assembly is used for Convert knee extension negative work into hip extension assist torque. Specifically, in the late swing phase, the second elastic element 10 provided in the assembly is stretched when the lower leg is stretched forward, and the elastic potential energy of the elastic element is not greater than the negative work performed when the lower leg is stretched forward, so that the lower leg can be stretched forward. The negative work done by the knee joint extension converts the elastic potential energy of the second elastic element, and the second elastic element recovers and releases the elastic potential energy when the thigh swings back in the early stage of the support phase, providing an auxiliary moment for the extension of the hip joint. Specifically, when the value range of the stiffness K ₂ of the second elastic element 10 is: 1.5≤K ₂ ≤4.0kN/m, it is satisfied that the elastic potential energy of the elastic element is not greater than the negative work performed when the calf stretches forward, and the swing is realized. The assistance requirements when the calf is extended forward.

Wherein, the first elastic element 4 or the second elastic element 10 is a tension spring or an elastic band. In this embodiment, the first elastic element and the second elastic element are respectively a thigh tension spring and a lower leg tension spring.

When in use, when the thigh swings back in the later stage of the support phase, the thigh energy storage assembly absorbs the negative work done when the thigh swings back, the thigh tension spring set in the thigh energy storage assembly is stretched, and the negative work done is converted into the tension spring's energy. The elastic potential energy is recovered and released (elastic potential energy) in the early swing phase to provide auxiliary torque for hip flexion; in the later stage of the swing phase, when the calf extends forward, the calf energy storage component absorbs the negative work done when the calf extends forward, and the calf tension spring is stretched The negative work done when the calf stretches forward is converted into elastic potential energy, and it is restored to provide an auxiliary torque for hip joint extension when the thigh swings back in the early support phase. Therefore, the present invention can utilize the conversion of negative work during walking to provide hip joint auxiliary torque, which can improve walking efficiency and reduce metabolic energy consumption.

Specifically, the waist fixing assembly includes an upper waist belt 1, a lower waist belt 2, a waist plate 8 and a cantilever beam unit. The waist plate 8 is divided into two left-right symmetrical pieces and is respectively fixed at the back waist of the user to provide a thigh energy storage assembly and a calf storage assembly. Connectivity platform for energy components. The upper waistband 1 and the lower waistband 2 are respectively bound to the user's upper abdomen and lower abdomen through both sides of the waist plate 8 , and the upper waistband 1 and the lower waistband 2 can be adjusted elastically according to the user's body shape. The upper waist belt 1 can prevent the waist plate from tilting backward when the rear suspension beam 9 is stressed, and the lower waist belt 2 can prevent the waist fixing component from falling off when the waist fixing component is stressed.

Preferably, reinforcing ribs are provided on the waist plate, and the reinforcing ribs are arranged along the direction in which the waist plate is stressed, which can enhance the strength and bending resistance of the waist plate. A weight reduction hole is also provided, and the weight reduction hole can reduce the weight of the device.

The cantilever beam unit is arranged on the waist plate 8 and is elastically connected with the first elastic element 4 and the second elastic element 10 . The cantilever beam unit includes a horizontal cantilever beam 12 , a horizontal cantilever beam fixing member 13 arranged at both ends of the horizontal cantilever beam 12 , two side suspension beams 3 , a side suspension beam fixing member 14 arranged at one end of the two side suspension beams 3 , and two rear suspension beams 9 . The other ends of the two side suspension beams 3 are fixedly connected to both sides of the waist plate 8; the side suspension beams have a plurality of sets of installation holes, which can be adjusted according to the user's body shape. Preferably, the side suspension beam fixing member 14 is fixed to the installation hole of the side suspension beam 3 by screws, and the lateral suspension beam fixing member 13 is fixed to the installation hole of the lateral suspension beam 12 by screws. The side suspension beam fixing member 14 and the lateral suspension beam fixing member 13 are fixed through bolts, and there is a snap lock between the two to prevent the two from rotating relative to each other, so as to fix the connection between the lateral suspension beam 12 and the two side suspension beams 3 . Both ends of the horizontal cantilever beam 12 are provided with a horizontal cantilever beam fixing member 13, which is installed on the front side of the abdomen of the human body. The horizontal cantilever beam 12 is provided with a plurality of installation holes, and one end of the first elastic element 4 passes through the installation holes on the horizontal cantilever beam. 12 is elastically connected, and the position of the first elastic element hanging on the horizontal cantilever beam can be adjusted according to the body shape of the user.

One end of the two rear suspension beams 9 is fixed to the lower part of the waist plate 8 by screws, and the other end is elastically connected with the second elastic element 10 respectively.

Preferably, in order to reduce weight, the waist fixing component is made by 3D printing. The material of the transverse suspension beam 12 and the two side suspension beams 3 is carbon fiber board, and the material of the waist plate 8 is resin or nylon glass fiber.

Preferably, the material of the thigh drawstring 5 , the calf drawstring 11 , the thigh strap 6 and the calf strap 7 is a flexible material.

The thigh energy storage assembly includes a first elastic element 4, a thigh drawstring 5 and a thigh strap 6, and two ends of the thigh drawstring 5 are respectively connected to one end of the first elastic element 4 and the thigh strap 6 for transmitting the first elastic element. 4 and the pulling force of the thigh strap 6; the length of the thigh cord can be adjusted, so that the first elastic element (the thigh tension spring in this embodiment) is in a state of being stretched just when the thigh is upright. The first elastic element 4 and the other ends of the thigh straps 6 are respectively arranged on the front side of the waist fixing assembly and the thigh. The value range of the stiffness K ₁ of the elastic element 4 is: when 0<K ₁ ≤ 3.5kN/m, it is satisfied that the elastic potential energy of the elastic element is not greater than the negative work done when the thigh is swayed back, and can absorb the negative work done when the thigh is swayed back. Negative work, and recovering and releasing energy in the early swing phase to provide hip joint flexion auxiliary moment; when the stiffness K ₁ of the first elastic element 4 >3.5kN/m, the elastic potential energy of the elastic element is greater than the negative work done when the thigh swings back , at this time, the exoskeleton will interfere with the natural movement of the human body and cannot help. The thigh strap 6 is fixed on the user's thigh for connecting the thigh energy storage assembly with the user.

The calf energy storage assembly includes a second elastic element 10 , a calf drawstring 11 and a calf strap 7 , and two ends of the calf drawstring 11 are respectively connected to the second elastic element 10 (calf tension spring in this embodiment) and the calf strap 7 . At one end of the calf pull cord, the length of the calf pull cord can be adjusted, so that the calf pull spring is just in the state of being stretched when the user stands upright.

The second elastic element 10 and the other ends of the calf straps 7 are respectively disposed on the back side of the waist fixing assembly and the lower leg. When the stiffness K ₂ of the second elastic element 10 is in the range of: _{1.5≤K2≤4.0kN} /m When the elastic potential energy of the elastic element is not greater than the negative work done when the calf stretches forward, so that when the calf stretches forward in the later swing phase, the calf energy storage component absorbs the negative work done when the calf stretches forward, and the calf tension spring is stretched The negative work done when the calf stretches forward is converted into elastic potential energy, and is restored to provide an auxiliary moment for hip joint extension when the thigh swings back in the early support phase; when the stiffness K ₂ of the second elastic element 10 is greater than 4.0kN/m, the The elastic potential energy of the elastic element is greater than the negative work done when the calf is stretched forward. At this time, the exoskeleton will interfere with the natural movement of the human body and cannot help. Moreover, when K ₂ <1.5kN/m, the elastic potential energy of the elastic element is far less than the negative work done when the lower leg is stretched forward, and at this time, it can not play a role of assisting. The calf strap is tied on the user's calf and is used to connect the calf energy storage assembly with the user.

Preferably, when the rigidity of the first elastic element 4 is 2.3 kN/m and the rigidity of the second elastic element 10 is 3.0 kN/m, the elastic potential energy of the first elastic element and the second elastic element are just the same as when the thigh swings back. It is equal to the negative work done when the calf stretches forward, that is, the negative work done by the thigh and the calf in the whole gait cycle is exactly converted into the elastic potential energy of the elastic element. At this time, the metabolic energy consumption of the human body is the lowest. Wherein, the optimal stiffness of the first elastic element and the second elastic element is an average value obtained by measuring a plurality of subjects with different body weights. When measurements were made on multiple subjects, the optimal stiffness differed very little in practice for each subject.

As shown in FIG. 4, it is a schematic diagram of the assisting exoskeleton assisting device in the whole gait cycle of the present invention. When the lower limb of the user is located on the front side of the human body, the first elastic element is at its original length, and the second elastic element is stretched. Assists the extension of the hip joint; when the user's lower limbs are located on the back side of the human body, the first elastic element is stretched, and the second elastic element is at the original length to assist the flexion of the hip joint.

Those skilled in the art can easily understand that the above are only preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present invention, etc., All should be included within the protection scope of the present invention.

Claims (10)

1. A passive exoskeleton booster device of hip and knee joint based on energy storage is characterized by comprising: the waist fixing component, the thigh energy storage component and the shank energy storage component are arranged on the upper portion of the waist fixing component;

the waist fixing component is fixed on the waist of a user and used for providing a fixed mounting platform for the thigh energy storage component and the shank energy storage component;

the two groups of thigh energy storage assemblies are arranged, each group of thigh energy storage assemblies comprises a first elastic element (4), a thigh pull rope (5) and a thigh binding belt (6), two ends of the thigh pull rope (5) are respectively connected with the first elastic element (4) and one end of the thigh binding belt (6), the other ends of the first elastic element (4) and the thigh binding belt (6) are respectively arranged on the front side of the waist fixing assembly and the thighs, when the thighs are swung backwards in the later supporting phase, the first elastic element (4) is stretched, and the elastic potential energy of the first elastic element (4) is not more than the negative work done when the thighs are swung backwards;

the energy storage assemblies for the lower legs are provided with two groups, each group of energy storage assemblies for the lower legs comprises a second elastic element (10), a lower leg pull rope (11) and a lower leg binding band (7), two ends of each lower leg pull rope (11) are respectively connected with the second elastic element (10) and one end of each lower leg binding band (7), the other ends of the second elastic elements (10) and the lower leg binding bands (7) are respectively arranged on the rear side of the waist fixing assembly and the lower legs, when the lower legs extend forwards in the later period of swinging, the second elastic elements (10) are stretched, and the elastic potential energy of the second elastic elements (10) is not more than the negative work done when the lower legs extend forwards.

2. Device according to claim 1, characterized in that the stiffness K of the first elastic element (4)₁The value range is as follows: k is more than 0₁Less than or equal to 3.5 kN/m; a stiffness K of the second elastic element (10)₂The value range is as follows: k is more than or equal to 1.5₂≤4.0kN/m。

3. The device according to claim 2, characterized in that the stiffness of the first elastic element (4) is 2.3kN/m and the stiffness of the second elastic element (10) is 3.0 kN/m.

4. A device according to any one of claims 1-3, characterized in that the first elastic element (4) or the second elastic element (10) is a tension spring or an elastic band.

5. The device according to claim 4, characterized in that the waist fixing component comprises an upper waist belt (1), a lower waist belt (2), a waist board (8) and a suspension beam unit, wherein the waist board (8) is divided into two bilaterally symmetrical pieces which are respectively fixed at the back waist of the user, the upper waist belt (1) and the lower waist belt (2) are respectively fixed at the upper abdomen and the lower abdomen of the user by penetrating through the waist board (8), and the suspension beam unit is arranged on the waist board (8) and is elastically connected with the first elastic element (4) and the second elastic element (10).

6. The device according to claim 5, wherein the suspension beam unit comprises a cross suspension beam (12), cross suspension beam fixing parts (13) arranged at two ends of the cross suspension beam (12), two side suspension beams (3), side suspension beam fixing parts (14) arranged at one ends of the two side suspension beams (3), and two rear suspension beams (9), wherein the cross suspension beam fixing parts (13) are connected with the side suspension beam fixing parts (14) through a snap-fit connection for fixedly connecting the cross suspension beam (12) and the two side suspension beams (3); the other ends of the two side suspension beams (3) are fixedly connected with the two sides of the waist plate (8); one ends of the two rear suspension beams (9) are fixedly connected with the lower part of the waist plate (8), and the other ends of the two rear suspension beams are respectively and elastically connected with the second elastic element (10).

7. The device according to claim 6, characterized in that a plurality of mounting holes are provided on the cross member (12), through which one end of the first elastic element (4) is elastically connected to the cross member (12).

8. The device according to claim 7, characterized in that the thigh stay (5) and the calf stay (11) are adjustable in length.

9. The device according to claim 8, characterized in that the thigh pull rope (5), the calf pull rope (11), the thigh strap (6) and the calf strap (7) are made of flexible materials, the cross suspension beam and the two side suspension beams are made of carbon fiber plates, and the waist plate is made of resin or nylon glass fiber.

10. The device as claimed in any one of claims 5 to 9, wherein the waist plate is provided with a reinforcing rib, and the reinforcing rib is arranged along the direction of the stress of the waist plate.

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