Waist walking aid exoskeleton control method and structure

Abstract

The invention relates to a waist walking aid exoskeleton control method and structure, and belongs to the technical field of exoskeletons. The control method comprises the following steps: determining a power gear upper limit according to the electric quantity of a battery and the temperature of a motor, and determining a current power gear and a working mode according to user settings; determining the numerical value of a motor torque control parameter according to the current gear and the working mode; performing gait detection and generating a target torque based on a gait state; limiting and smoothing the target torque based on the set motor torque control parameters; the absolute value of the included angle of the left and right thigh connecting rods is monitored in real time, and if the absolute value exceeds a threshold value, the target torque is forcibly set to be zero; and sending the finally obtained target torque to a motor for execution. The device can adapt to gait changes of a user in different scenes such as uphill and downhill, timely and appropriate waist and lower limb assistance is provided, the human body load is effectively relieved, and the exercise comfort and safety are improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of exoskeleton, in particular to a waist walking aid exoskeleton control method and structure. BACKGROUND

[0002] As an important branch of robotics, exoskeleton technology has been widely used in medical rehabilitation, industrial assistance and military protection in recent years. The waist assistance exoskeleton aims to reduce the load on the human waist by providing external assistance, and reduce the risk of muscle fatigue and injury.

[0003] There are many waist exoskeleton design schemes in the prior art, such as the waist assistance exoskeleton mechanism proposed in patent CN110842896. Although this kind of technology has achieved the assistance function to some extent, it mainly faces the industrial bending work scene and focuses on the assistance of forward bending action of the trunk. This kind of prior art often has insufficient adaptability to continuous ramp walking scenes, and it is difficult to effectively respond to the dynamic changes of human posture and torque demand during uphill and downhill processes. SUMMARY

[0004] To solve the problems in the prior art, the present application proposes a waist walking aid exoskeleton control method and structure.

[0005] The present application adopts the following technical solutions: In a first aspect, the present application proposes a control method for a waist walking aid exoskeleton, comprising the following steps: S1. Determine the upper limit of the power gear according to the battery capacity and the motor temperature, and determine the current power gear and the working mode according to the user settings; S2. Determine the value of the motor torque control parameter according to the current gear and the working mode; S3. Perform gait detection and generate a target torque based on the gait state; S4. Limit and smooth the target torque based on the set motor torque control parameter; S5. Real-time monitor the absolute value of the left and right thigh connecting rod angle, if the absolute value exceeds the threshold, the target torque is forcibly set to zero; S6. Send the finally obtained target torque to the motor for execution.

[0006] In uphill and downhill application scenarios, the human gait cycle, joint angle and moment demand will change significantly and rapidly, and the traditional constant parameter control method is difficult to adapt to such dynamic fluctuations. The control method of the application can accurately determine the gait phase according to the real-time detection of the angle and angular velocity difference of the left and right thigh connecting rods and the dynamic threshold, ensure that the assistive torque is applied to the correct leg at the correct gait moment, and make the assistive torque highly synchronized with the human motion intention, which conforms to the natural gait law. The application also uses a torque change rate limit that is adaptively adjusted according to the average angular velocity. This mechanism can ensure that the assistive torque smoothly transitions as the walking speed increases or decreases, avoiding user instability due to sudden torque changes on unstable slopes, and ensuring motion continuity and safety.

[0007] Preferably, in step S1, the power gear upper limit is determined by taking the minimum value of the maximum power gear supported by the battery power and the maximum power gear supported by the motor temperature; the equipment state is comprehensively evaluated to avoid over-discharge or overheating, and the system safety is improved; The maximum power gear supported by the battery power corresponds to different gear values in different intervals of the battery power, and the lower the battery power, the lower the maximum power gear value. Intelligent downshift is performed at low power to ensure continuous operation of the equipment; The maximum power gear supported by the motor temperature corresponds to different gear values in different intervals of the motor temperature, and the higher the motor temperature, the lower the maximum power gear value, which prevents the motor from overheating and being damaged.

[0008] Preferably, the motor torque control parameters in step S2 include maximum torque limit, angular torque coefficient, maximum torque change rate, minimum torque change rate, and high-speed zone torque change rate upper limit; the parameters are set according to the current gear and mode, so as to realize different output intensities and adapt to different walking modes.

[0009] Preferably, in step S3, the gait detection includes detecting the angle and angular velocity difference of the left and right thigh connecting rods, and determining the gait according to a preset rule; The preset rule is to determine that the first gait is entered when the angle is less than a negative angle threshold and the angular velocity difference is greater than an angular velocity difference threshold, and to determine that the second gait is entered when the angle is greater than an angle threshold and the angular velocity difference is less than a negative angular velocity difference threshold. This rule conforms to the characteristics of human gait and has high recognition accuracy; The calculation expression of the angular velocity difference threshold is: By dynamically adjusting the threshold, the adaptability to different step speeds is enhanced.

[0010] Preferably, the step of generating the target torque in step S3 comprises: If in the first step, the target torque of the left motor is calculated and the target torque of the right motor is the opposite number of , If in the second step, the target torque of the right motor is calculated and the target torque of the left motor is the opposite number of ; The calculation expression of the target torque is Wherein, is the target torque of the left or right motor, is the angular torque coefficient, is the maximum value of the left and right thigh connecting rod angle, is the angle correction coefficient, is the time decay coefficient, is the stasis zone damping coefficient, is the speed gain coefficient. The target torque is adjusted by multiple factors to output more in line with actual needs.

[0011] Preferably, in step S4, If the target torque exceeds the maximum torque limit , the target torque is adjusted to , If the target torque is lower than the negative maximum torque limit , the target torque is adjusted to . This limiting mechanism can prevent overloading and ensure the safety of the equipment and users.

[0012] Preferably, in step S4, The torque change rate limit is adjusted according to the average angular velocity of the left and right thigh connecting rods , ensuring that the change amount of the target torque in each update does not exceed the adjusted torque change rate limit ; This measure can make the torque change smoother, reduce the jerk, and improve comfort.

[0013] Wherein, When the average angular velocity is less than 60° / s, linear interpolation between the maximum torque change rate and the minimum torque change rate ; When the average angular velocity is between 60° / s and 100° / s, Δτ is linearly interpolated between the maximum torque change rate Linear interpolation between the high speed zone torque rate upper limit and the high speed zone torque rate upper limit When the average angular velocity is greater than 100° / s, The value of the high speed zone torque rate upper limit According to different motion states, the torque rate limit is adaptively adjusted, and the response speed and smoothness are considered.

[0014] In a second aspect, the present application further provides a waist walking aid exoskeleton structure for implementing the above control method, comprising a control integrated module and a waist connecting rod passing through the control integrated module and fixed with the control integrated module, the waist connecting rod is fixed with a left motor and a right motor at both ends respectively, the output ends of the left motor and the right motor are fixed with upper ends of a thigh connecting rod respectively, a thigh binding module is connected to a lower end of the thigh connecting rod, the thigh binding module is used for fixing with a thigh of a user, and the control integrated module is further connected with an upper body fixing module used for fixing with an upper body of the user. The waist walking aid exoskeleton structure highly integrates power control and energy unit in the waist, stabilizes the gravity center, optimizes the overall structure design, makes the exoskeleton more portable and flexible, and is particularly suitable for dynamic scenes such as uphill and downhill walking, and realizes the unification of efficient assistance and wearing comfort.

[0015] Preferably, the control integrated module comprises a battery compartment, a main control board and a control terminal arranged outside the motor, the motor is electrically connected with the main control board, and the control terminal is used for adjusting gears and working modes. The control terminal arranged outside the motor is closer to the hands of the user, is convenient for the user to adjust in real time, and improves the use convenience.

[0016] Preferably, the thigh binding module comprises a thigh baffle and a thigh bandage, the thigh baffle is connected with the thigh connecting rod, and the thigh bandage is used for fixing the thigh baffle on the thigh of the user; the upper body fixing module comprises a waistband and a shoulder strap, the waistband is fixed with the control integrated module, the shoulder strap is connected with the waistband, and a split buckle and a hook-and-loop fastener are arranged on the waistband and used for adjusting the girth; the thigh binding module and the upper body fixing module adopt a multi-dimensional adjusting bandage structure, have good adaptability and comfort, can adapt to users with different body shapes, and enhance the wearing stability.

[0017] In summary, the present application realizes dynamic adjustment and control of waist and lower limb assistance through the combination of structural design and intelligent control method, can effectively reduce the muscle burden of the user in various scenes such as walking, uphill and downhill, and improves the motion comfort and safety. BRIEF DESCRIPTION OF DRAWINGS

[0018] Figure 1 It is a structural schematic view of the waist walking aid exoskeleton of the present application; Figure 2Figure 1 is a schematic diagram of the back structure of the waist walking aid exoskeleton of the present application. Figure 3 Figure 2 is a schematic diagram of the upper body fixing module structure of the waist walking aid exoskeleton of the present application.

[0019] Reference signs: 1-control integrated module, 2-motor module, 3-thigh binding module, 4-upper body fixing module, 5-thigh connecting rod, 6-waist connecting rod, 21-control terminal, 51-output connecting piece, 31-thigh baffle, 32-thigh binding belt, 41-waistband, 42-shoulder strap, 43-adjusting buckle, 44-magnetic fastener, 45-split buckle, 46-connecting belt ring, 47-thickened waist back cloth, 48-thickened crotch cloth. DETAILED DESCRIPTION

[0020] In order to further illustrate the technical means and effects adopted by the present application to achieve the predetermined purposes, the specific embodiments, structures, features and effects according to the present application are described in detail below in combination with the drawings and preferred embodiments.

[0021] Example 1 As shown in Figure 1 and Figure 2 , a waist walking aid exoskeleton structure includes a control integrated module 1, a motor module 2, a thigh binding module 3, an upper body fixing module 4, a thigh connecting rod 5 and a waist connecting rod. The waist connecting rod is in the shape of C as a whole, the middle part penetrates through the control integrated module 1, and both ends are connected with two motor modules 2; the thigh connecting rod 5 connects the motor module 2 and the thigh binding module 3. The control integrated module 1 includes a shell, a battery compartment and a main control board arranged in the shell, the shell is fixed with the middle part of the waist connecting rod, a rechargeable battery is placed in the battery compartment, and the battery is replaceable.

[0022] The motor module 2 comprises a shell, a motor arranged in the shell, and a control terminal 21 arranged on the shell. The motor is electrically connected with the main control board. The motors in the two motor modules 2 are respectively referred to as left motor and right motor. The waist connecting rod is internally hollow to leave a wiring space. The wires connected between the motor and the main control board are arranged in the wiring space in the waist connecting rod. The upper end of the thigh connecting rod 5 is hingedly connected with an output connecting piece 51. The output connecting piece 51 is further connected with the output end of the motor through a rotating shaft. The hinging shaft of the thigh connecting rod 5 and the output connecting piece 51 is perpendicular to the motor output shaft and the length direction of the thigh. Through the output connecting piece 51, the thigh connecting rod 5 is driven to rotate by the motor, and further provides assistance or resistance for the leg lifting action of the user through the thigh binding module 3. Meanwhile, the hinging of the thigh connecting rod 5 and the output connecting piece 51 allows the thigh connecting rod 5 to be adjusted to fit the thigh periphery. The control terminal 21 of the motor module 2 comprises a plurality of buttons, including a start-stop button, a mode adjustment button, a gear adjustment button, etc. The buttons are electrically connected with the main control board of the control integrated module 1. The wires connected therebetween are arranged in the wiring space in the waist connecting rod. The control terminal 21 is further provided with a gear prompt lamp for displaying the current output gear of the exoskeleton.

[0023] In an embodiment, the thigh binding module 3 comprises a thigh baffle 31 and a thigh binding belt 32. The thigh baffle 31 is fixedly connected with the lower end of the thigh connecting rod 5. The inner side of the thigh baffle 31 is in curve conformity with the outer surface of the thigh. The thigh baffle 31 is provided with two binding belt holes. The thigh binding belt 32 passes through the two binding belt holes to bind the thigh of the user, so as to fix the thigh baffle 31 with the thigh of the user. Specifically, the thigh binding belt 32 is provided with a Velcro structure at one end and an adjusting buckle 43 at the other end. The Velcro structure is passed through the adjusting buckle 43 and then adhered with itself, so as to realize the binding fixation conforming to the thigh of the user.

[0024] In another embodiment, the thigh binding module 3 further comprises a baffle connecting piece. The thigh baffle 31 is connected with the lower end of the thigh connecting rod 5 through the baffle connecting piece. The baffle connecting piece is slidingly connected with the thigh connecting rod 5. The sliding direction is the same as the length direction of the thigh. The baffle connecting piece is hingedly connected with the thigh baffle 31, so as to realize the double-degree-of-freedom movement of the thigh baffle 31.

[0025] As Figure 3As shown, the upper body fixing module 4 includes a waistband 41 and a back strap 42. The middle of the waistband 41 is fixed with the control integrated module 1, and the waistband 41 is wrapped around the waist of the user and fastened by split buckles 45 and Velcro 44. Specifically, the outer side of each end of the waistband 41 at least 5 cm away from the top end is sewn with a connecting band ring 46, and the connecting band ring 46 is connected with an adjusting buckle 43; the Velcro 44 has two strips, and each of the two strips of Velcro 44 is fixed to the two ends of the split buckle 45, and each of the two strips of Velcro 44 at the two ends of the split buckle 45 is respectively passed through the adjusting buckle 43 and then adhered to itself. The two extra sections of the waistband 41 at the two ends are located on the inner side of the adjusting buckle 43 to avoid the hard texture of the adjusting buckle 43 from giving the user discomfort. The design of the Velcro 44 facilitates the user to adjust the length of the waistband 41 according to his own waist circumference, and the split buckle 45 can be easily separated and buckled, which is convenient to wear. The middle of the waistband 41 is widened to shield the contact between the back of the control integrated module 1 and the user's back waist. The middle of the waistband 41 is also adhered or sewn with a back waist thickening cloth 47 which is larger in size than the back of the control integrated module 1, for reducing the discomfort of the user caused by the hard texture of the back of the control integrated module 1. On the left and right sides of the crotch of the user, two crotch thickening cloths 48 are also provided, which are respectively connected with the waistband 41, for reducing the discomfort of the user caused by the hard texture of the motor module 2 and the output connecting piece 51.

[0026] The upper edge of the middle of the waistband 41 and the upper edge of each end of the waistband 41 are each sewn with a connecting band ring 46, and the connecting band ring 46 is connected with an adjusting buckle 43, and there are three adjusting buckles 43. The back strap 42 includes three back straps 42 connected together at the ends, and each of the three back straps 42 is connected with one of the three adjusting buckles 43 on the upper edge of the waistband 41. Through the three adjusting buckles 43, the user can conveniently adjust and select the appropriate length of the back strap 42.

[0027] Embodiment 2 The control method of the waist-assisted exoskeleton structure of embodiment 1, comprising the following steps S1 to S5.

[0028] S1. Adjust the upper limit of the power gear according to the battery capacity and the left and right motor temperature, and determine the current power gear and working mode according to the user setting: 1.1. First, calculate the maximum power gear supported by the battery capacity b according to the battery capacity b, The battery capacity is measured in percentage, When b < 10%, = 1; When 10% ≤ b < 20%, = 3; When 20% ≤ b < 30%, = 5; When 30% ≤ b < 40%, = 6; When 40%≤b<50%, =7; When b≥50%, =8; 1.2. Calculate the maximum power gear that the motor temperature can support according to the temperature of the motor with the highest temperature among the two motors of the exoskeleton 1.3. Calculate the maximum power gear that the battery power can support The unit of temperature is Celsius, When , ; When , ; When , ; When , ; 1.3. Take the minimum value of the maximum power gear that the battery power can support and the maximum power gear that the motor temperature can support as the upper limit of the power gear ; The user's settable gear is limited to the upper limit of the power gear and below; 1.4. Determine the current working mode according to the user's setting, which includes climbing mode and descending mode. Step 1.4 has no sequence relationship with other steps in step 1.

[0029] S2. Determine the value of the motor torque control parameter according to the current gear and working mode: Different gears (1-8 gears) and working modes have corresponding motor torque control parameter values. According to the current gear and working mode, the value of the motor torque control parameter is determined. The motor torque control parameter includes maximum torque limit , angle torque coefficient , angle correction coefficient , stasis zone damping coefficient , speed gain coefficient , maximum torque change rate , minimum torque change rate , high-speed zone torque change rate upper limit , where the unit of maximum torque limit is Nm, and torque change rate represents the relationship between speed and torque change.

[0030] S3. Gait detection and torque generation: 3.1. Detect the included angle (unit: degrees) and angular velocity difference (unit: ° / s) of the left and right thigh connecting rods 5, and calculate the motor torque according to the current included angle computing the angular velocity difference threshold , setting the included angle threshold of the left and right thigh connecting rods 5 ; judging the current gait according to the included angle and the angular velocity difference , the gait including a first gait and a second gait, in the first gait, the right foot supports and the left foot swings, in the second gait, the left foot supports and the right foot swings; the angular velocity difference threshold The calculation expression is In this embodiment, only the case where the included angle changes between -40° and 0° is considered; When the included angle is less than and the angular velocity difference is greater than , the first gait is entered; When the included angle is greater than and the angular velocity difference is less than , the second gait is entered; 3.2. If the current gait is the first gait, the target torque of the left motor is calculated, and the target torque of the right motor is taken as its opposite number, and the calculation expression is as follows If the current gait is the second gait, the target torque of the right motor is calculated, and the target torque of the left motor is taken as its opposite number, and the calculation expression is as follows Wherein, T represents the target torque of the right motor, T represents the target torque of the left motor, K represents the angle torque coefficient, θmax represents the maximum value of the included angle of the left and right thigh connecting rods 5 in the first state, K represents the angle correction coefficient, which is a preset constant value, , K represents the time decay coefficient, the time decay coefficient smoothly decreases from 1 to 0 after the state switching, K represents the stagnation zone damping coefficient, which is a preset constant value, , K represents the speed gain coefficient, which is a preset constant value, .

[0031] S4. Limit and smooth the target torque of the two motors respectively: 4.1. If the target torque exceeds the maximum torque limit , the target torque is adjusted to be equal to the maximum torque limit , if the target torque is lower than the opposite of the maximum torque limit , the target torque is adjusted to be equal to the opposite of the maximum torque limit ; 4.2. Adjust the torque rate limit according to the average angular velocity of the left and right thigh connecting rods 5 , and use the adjusted torque rate limit to smooth the target torque and , ensuring that the amount of change in the target torque at each update does not exceed the torque rate limit , the average angular velocity of the left and right thigh connecting rods 5 is the average of the angular velocity of the left thigh connecting rod 5 and the angular velocity of the right thigh connecting rod 5, and the adjustment rule is: When the average angular velocity of the left and right thigh connecting rods 5 is less than 60° / s, the torque rate limit is linearly interpolated between the maximum torque rate and the minimum torque rate ; When the average angular velocity of the left and right thigh connecting rods 5 is between 60° / s and 100° / s, the torque rate limit is linearly interpolated between the maximum torque rate and the high-speed zone torque rate ; When the average angular velocity of the left and right thigh connecting rods 5 is greater than 100° / s, the torque rate limit is equal to the high-speed zone ; In this embodiment, the minimum torque rate is 0.1, the maximum torque rate and the high-speed zone torque rate change with the gear; If the target torque or differs from the target torque at the previous moment by more than the torque rate limit , the sum of the target torque at the previous moment and is taken as the value of the target torque or .

[0032] S5. While performing S1-S4, monitor whether the absolute value of the current angle between the left and right thigh connecting rods 5 exceeds 120°, if so, trigger the safety protection mechanism, forcibly set the target torque of the left and right motors to 0, and immediately perform step S6; S6. The final calculated target torque and is sent to the left and right motors for execution.

[0033] The actual test shows that the waist walking aid exoskeleton can provide stable and natural assistance effect under various road conditions, the user feedbacks that wearing is comfortable, operation is simple, assistance response is timely and there is no obvious lag feeling. And the application performs excellently in complex environments such as uphill and downhill, significantly reduces the burden of lower limbs, has high practical value and popularization prospect.

[0034] The above is only a preferred embodiment of the present application, and does not limit the present application in any form. Although the present application has been disclosed as above with a preferred embodiment, it is not intended to limit the present application. Any person skilled in the art can make slight changes or modifications to the above disclosed technical content to obtain equivalent embodiments with equivalent changes, without departing from the technical solution range of the present application. Any modification, equivalent change and modification of the above embodiments made according to the technical essence of the present application still belong to the scope of the technical solution of the present application.

Claims

1. A control method for a lumbar walking assistive exoskeleton, the lumbar walking assistive exoskeleton comprising a battery, a left-side motor and a right-side motor located on both sides of the hip, and left and right thigh connecting rods driven by the motors, characterized in that, Its characteristic is that it includes the following steps: S1. Determine the upper limit of the power level based on the battery charge and motor temperature, and determine the current power level and working mode based on user settings; S2. Determine the values ​​of the motor torque control parameters based on the current gear and working mode; S3. Perform gait detection and generate target torque based on gait state; S4. The target torque is limited and smoothed based on the set motor torque control parameters; S5. Monitor the absolute value of the angle between the left and right thigh connecting rods in real time. If the absolute value exceeds the threshold, the target torque is forcibly set to zero. S6. Send the final target torque to the motor for execution.

2. The control method according to claim 1, characterized in that, In step S1, the upper limit of the power level is determined by taking the minimum value between the maximum power level supported by the battery capacity and the maximum power level supported by the motor temperature. The maximum power level supported by the battery capacity corresponds to different levels depending on the battery capacity range. The lower the battery capacity, the lower the corresponding maximum power level. The maximum power level supported by the motor temperature corresponds to different levels depending on the different temperature ranges of the motor. The higher the motor temperature, the lower the corresponding maximum power level.

3. The control method according to claim 1, characterized in that, The motor torque control parameters mentioned in step S2 include maximum torque limit, angular torque coefficient, maximum torque change rate, minimum torque change rate, and upper limit of torque change rate in the high-speed zone.

4. The control method according to claim 3, characterized in that, The gait detection in step S3 includes detecting the angle between the left and right thigh connecting rods. and angular velocity difference And determine the gait according to preset rules; The preset rule is that when the included angle Less than the negative included angle threshold and angular velocity difference When the angular velocity difference is greater than the threshold, the system enters the first step state. Greater than the included angle threshold and the angular velocity difference When the difference in angular velocity is less than the negative threshold, the system is considered to enter the second gait state. The angular velocity difference threshold The calculation expression is as follows 。 5. The control method according to claim 4, characterized in that, The steps in step S3 to generate the target torque include: If in the first state, calculate the target torque of the left motor. And the target torque of the right motor for The opposite number, If in the second step state, calculate the target torque of the right motor. And the target torque of the left motor for The opposite number; The expression for calculating the target torque is as follows: in, The target torque for the left or right motor. This is the angular torque coefficient. This represents the maximum angle between the connecting rods of the left and right thighs. This is the angle correction factor. The time decay coefficient, The damping coefficient in the stagnation region is... This is the velocity gain coefficient.

6. The control method according to claim 3, characterized in that, In step S4, If the target torque exceeds the maximum torque limit Then adjust the target torque to , If the target torque is lower than the negative maximum torque limit - Then adjust the target torque to - .

7. The control method according to claim 3, characterized in that, In step S4, the torque change rate limit is adjusted according to the average angular velocity of the left and right thigh connecting rods. Ensure that the target torque change in each update does not exceed the adjusted torque change rate limit. ; When the average angular velocity is less than 60° / s, At the maximum torque change rate With minimum torque change rate Linear interpolation between them When the average angular velocity is between 60° / s and 100° / s At the maximum torque change rate Upper limit of torque change rate in high-speed region Linear interpolation between them When the average angular velocity is greater than 100° / s The value is the upper limit of the torque change rate in the high-speed region. .

8. A lumbar walking aid exoskeleton structure for implementing the control method according to any one of claims 1-7, characterized in that, The device includes a control integration module and a waist connecting rod that passes through and is fixed to the control integration module. A left motor and a right motor are fixed to both ends of the waist connecting rod, and the output ends of the left motor and the right motor are each fixed to the upper end of a thigh connecting rod. A thigh binding module is connected to the lower end of the thigh connecting rod. The thigh binding module is used to fix the user's thigh. The control integration module is also connected to an upper body fixing module for fixing the user's upper body.

9. The lumbar walking aid exoskeleton according to claim 1, characterized in that, The control integration module includes a battery compartment, a main control board, and a control terminal located outside the motor. The motor is electrically connected to the main control board, and the control terminal is used to adjust the gear and working mode.

10. The lumbar walking aid exoskeleton according to claim 1, characterized in that, The thigh binding module includes a thigh baffle and thigh straps. The thigh baffle is connected to the thigh connecting rod, and the thigh straps are used to fix the thigh baffle to the user's thigh. The upper body fixing module includes a waist belt and a back strap. The waist belt is fixed to the control integration module, and the back straps are connected to the waist belt. The waist belt is provided with a split buckle and a hook and loop fastener for adjusting the circumference.

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