Active and passive fused upper limb exoskeleton and control method thereof

Abstract

The invention discloses an active and passive fused upper limb exoskeleton and a control method thereof, and belongs to the technical field of exoskeletons.The active and passive fused upper limb exoskeleton comprises a waistband, a strap, a passive energy storage mechanism, an active power assisting mechanism and two sets of arm bands, two supporting rods are arranged on the two sides of the waistband, the lower ends of the two supporting rods are hinged to the waistband, and clutch boxes are fixedly arranged at the upper ends of the two supporting rods; a moment arm ring and a wire spool are rotationally arranged in the clutch box, and a big arm connecting rod is fixed on the moment arm ring and connected with an arm belt; the passive energy storage mechanism is fixedly connected with the wire spool through an inhaul cable; the active power assisting mechanism is connected with the wire spool through a Bowden wire; the clutch box is further provided with a linkage shaft which enables the wire spool and the force arm ring to be in power connection. The active power assisting mechanism has the following advantages that multiple power assisting modes are achieved, power assisting is flexibly adjusted according to individual differences and different requirements of operators, the endurance time of the active power assisting mechanism is effectively prolonged, and the working efficiency is improved; and power connection between the force arm ring and the wire spool is controlled through the linkage shaft, the structure is simple, and operation is convenient.

Description

Technical Field

[0001] This invention relates to the field of exoskeleton technology, and in particular to an active-passive integrated upper limb exoskeleton and its control method. Background Technology

[0002] Currently, in typical work scenarios such as industrial assembly, logistics handling, construction, and equipment maintenance, workers need to perform overhead lifting, supporting, installation, and assembly operations for extended periods. During these overhead operations, the shoulder joints and upper arm muscles bear a significant load continuously, easily leading to muscle fatigue. Long-term or high-frequency overhead work can also induce occupational musculoskeletal diseases such as rotator cuff injuries and frozen shoulder, not only harming the health of workers but also reducing work efficiency and increasing safety risks. To reduce the burden on the upper limbs during overhead work, various exoskeleton assistive devices for assisting upper limb movements have emerged in recent years. Existing upper limb assistive exoskeletons can be mainly divided into two categories: active and passive.

[0003] Active upper limb exoskeletons typically rely on motors, hydraulic or pneumatic drives to provide assistance, offering significant auxiliary torque and making them suitable for high-load work conditions. However, these exoskeletons generally suffer from complex structures, high energy dependence, and limited battery life, potentially increasing the burden on users during extended wear.

[0004] Passive upper limb exoskeletons typically employ elastic elements (such as tension springs, coil springs, or elastic ropes) as energy storage and release devices. They recover mechanical energy during human movement and release it at appropriate stages to support and assist upper limb movements. These exoskeletons offer advantages such as simple structure, light weight, no external power source required, and easy maintenance, and can reduce muscle load during overhead work to some extent. However, existing passive upper limb exoskeletons still have significant shortcomings in practical applications. Because their assistance relies primarily on elastic elements with fixed parameters, the amount of assistance is difficult to adjust flexibly according to individual differences in workers (such as height, weight, and muscle strength) and different task load requirements. In actual use, insufficient assistance may fail to effectively reduce fatigue, while excessive assistance may lead to restricted movement, decreased flexibility, or even safety hazards, limiting the applicability and comfort of passive exoskeletons in overhead work scenarios. Summary of the Invention

[0005] In view of the above-mentioned shortcomings of the existing technology, the purpose of this invention is to solve the technical problems of the single assistance mode and inconvenient assistance range adjustment of the existing exoskeleton, and to provide an active and passive integrated upper limb exoskeleton and its control method, which has multiple assistance modes. It can not only extend the endurance of the active exoskeleton, but also increase the assistance adjustment range of the passive exoskeleton, improve work efficiency, and prevent insufficient resistance from effectively reducing fatigue or excessive assistance from causing movement restriction and physical injury.

[0006] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows: an active and passive integrated upper limb exoskeleton, comprising a waist belt, a back belt, and two sets of arm belts, wherein the back belt and the waist belt are fixedly connected, and the two arm belts are respectively located on the left and right sides of the back belt; two support rods are also provided on the left and right sides of the waist belt, the lower ends of the two support rods are hinged to the waist belt, and a clutch box is fixedly provided on the upper end of each support rod; the bottom of the clutch box is an open structure, and a lever arm ring and a winding reel are provided inside the clutch box. The lever arm ring and the winding reel are rotatably connected to the inner walls of the clutch box on opposite sides through bearings. A large arm connecting rod is fixed on the lever arm ring, and the end of the large arm connecting rod away from the lever arm ring extends from the bottom of the clutch box and is connected to the arm belt. A first winding groove and a second winding groove are provided on the outer peripheral wall of the winding reel;

[0007] The clutch box also has a linkage shaft. One end of the linkage shaft is connected to an operating mechanism, and the other end extends into the clutch box and passes through the winding reel and the lever arm ring in sequence. A sliding key is provided on the outer wall of the linkage shaft along its axial direction. A first keyway is formed on the inner side of the winding reel along the axial direction of the linkage shaft, and a second keyway is formed on the inner side of the lever arm ring along the axial direction of the linkage shaft. The operating mechanism can drive the linkage shaft to slide back and forth along its axial direction. In the initial state, the sliding key and the lever arm ring are in a separated state. When the operating mechanism drives the linkage shaft to move, the sliding key on the linkage shaft can enter the first keyway and the second keyway, so that the winding reel and the lever arm ring are dynamically connected.

[0008] The support rod is a hollow rod body with a passive energy storage mechanism inside. The passive energy storage mechanism is connected to one end of a cable, and the other end of the cable is wound in a first winding groove and fixedly connected to a winding reel. An active assist mechanism is provided on the rear side of the belt. The active assist mechanism contains a Bowden wire. One end of the active assist mechanism is connected to the Bowden wire, and the other end of the Bowden wire is wound in a second winding groove and connected to a winding reel.

[0009] The present invention has the following advantages: it has both a passive energy storage mechanism and an active assist mechanism, and has multiple assist modes. It can flexibly adjust its assist according to the individual differences of the operators and the different task load requirements, effectively extending the endurance of the active assist mechanism, improving work efficiency, and preventing insufficient assistance from failing to effectively reduce fatigue or excessive assistance from causing limited movement and physical injury; and the linkage shaft slides to control the connection and separation of the force arm ring and the winding reel, making the structure simple and easy to operate.

[0010] Preferably, the operating mechanism includes a connector and a cam; one end of the linkage shaft extending out of the clutch box side wall is detachably connected to the connector; the connector is rotatably connected to the cam via a rotating pin, the outer contour of the cam abuts against the outer wall of the clutch box, and can drive the linkage shaft to slide along its axial direction.

[0011] The beneficial effects of the above-mentioned further solution are: when the cam rotates, the displacement generated by its outer contour abutting against the outer wall of the clutch box drives the linkage shaft to rotate. The structure is simple, and the manual operation structure can minimize the size and weight of the mechanism.

[0012] Preferably, a threaded post is fixedly provided at one end of the linkage shaft that is connected to the connector. The threaded post is coaxial with the linkage shaft. A connecting hole is provided at one end of the connector facing the linkage shaft. The connecting hole is threadedly connected to the threaded post.

[0013] The advantages of the above-mentioned further solutions are: the linkage shaft is connected to the connecting parts through the threaded post and the connecting parts, which makes disassembly and replacement convenient; the number of features of a single part is reduced, which facilitates processing; in addition, the starting position of the linkage shaft when sliding in the through hole can be changed by changing the depth of the threaded post screwed into the connecting hole.

[0014] Preferably, the clutch box has a through hole on the side wall through which the linkage shaft passes. A third keyway is formed on the inner side of the through hole along the axial direction of the linkage shaft. When the linkage shaft slides away from the lever arm ring, the sliding key of the linkage shaft disengages from the second keyway and enters the first keyway and the third keyway.

[0015] The beneficial effects of the above-mentioned further solution are: after the sliding key disengages from the second keyway and enters the first and third keyways, the lever arm ring can rotate freely, while restricting the rotation of the linkage shaft and the winding disc, making it easier to determine the angle position of the winding disc and facilitating the re-establishment of the power connection.

[0016] Preferably, the lower ends of the two support rods are fixedly provided with lower fixing members, the lower end of the lower fixing members being ball heads, and the left and right sides of the belt are respectively provided with a base, the ball head rotating within the base and forming a ball hinge; the upper ends of the support rods are fixedly provided with upper fixing members, which are fixedly connected to the clutch box through two support arms.

[0017] The beneficial effect of the above-mentioned further solution is that it allows the shoulder position where the clutch box is located and the arm position where the arm strap is located to rotate freely, improving the flexibility and comfort of use.

[0018] Preferably, the passive energy storage mechanism includes a sliding member, a first spring, a cable, and a fixed pulley; the top surface of the upper fixing member has an installation groove, and the fixed pulley is installed in the installation groove; the sliding member is slidably located inside the support rod, and the first spring is located between the top surface of the sliding member and the bottom surface of the upper fixing member; one end of the cable is fixedly connected to the sliding member, and the other end passes through the upper fixing member, extends into the installation groove, passes around the fixed pulley, and extends into the clutch box to connect with the winding reel.

[0019] The beneficial effects of the above-mentioned further solution are as follows: When the winding reel and the lever arm are connected, the operator swings the arm downward to drive the boom linkage, the boom linkage drives the winding reel to rotate, the winding reel drives the cable, the cable pulls the sliding part upward, thereby compressing the first spring to store kinetic energy. Relying on the spring for passive energy storage, the structure is simple. When the operator raises the arm upward, the elastic potential energy of the first spring is released, which helps the operator raise the arm and reduces muscle fatigue and labor intensity.

[0020] Preferably, two adjustment belts are fixedly provided on the left and right sides of the waist belt, and several positioning holes are opened on the adjustment belts along the length direction of the waist belt; the base is slidably installed on the adjustment belts, and an installation cylinder is fixedly provided on the base. The installation cylinder is open to one side facing the adjustment belts, and a positioning post is slidably provided inside it. A second spring is provided between the bottom of the installation cylinder and the positioning post, which is used to push the positioning post to slide out from the open side of the installation cylinder and extend into the positioning hole; a handle is also provided at the end of the installation cylinder away from the adjustment belts, and a connecting rod is fixedly provided on the handle. The connecting rod passes through the bottom of the installation cylinder, extends into the installation cylinder, and is detachably connected to the positioning post.

[0021] The beneficial effects of the above-mentioned further solutions are: the sliding base can adjust the connection position between the support rod and the waist belt, adapting to workers of different body shapes and shoulder widths, thus improving the versatility of the exoskeleton; and it is fixed by the positioning pins being inserted into the positioning holes, making adjustment convenient.

[0022] Preferably, the active assist mechanism includes a housing fixed to the rear side of the belt. Inside the housing are two sets of motors corresponding to two clutch boxes respectively. Each motor has a drive wheel on its output shaft. Bowden wire is wound around the drive wheel, with one end of the Bowden wire fixedly connected to the drive wheel and the other end extending into the clutch box and connected to the winding reel. The housing also includes a battery and a controller. The controller is electrically connected to the two motors through an interface, and the battery is electrically connected to the motors and the controller to supply power to them.

[0023] The beneficial effects of the above-mentioned further solution are: the two motors drive the winding reels on both shoulders respectively, which can be controlled according to the actual load conditions, providing appropriate auxiliary support, thereby effectively reducing the burden on the shoulder and upper limb muscles of the operator and improving the comfort and stability during long-term overhead operations.

[0024] Preferably, the active assist mechanism further includes an attitude sensor and a force sensor, which are mounted on the armband and electrically connected to the controller.

[0025] The benefits of the above-mentioned further solutions are: they facilitate real-time monitoring of attitude and load data, enable real-time adjustments, and provide better support.

[0026] This invention also provides a control method using the above-mentioned active-passive fusion upper limb exoskeleton, the specific steps of which are as follows:

[0027] When the active assist mechanism is activated, the controller acquires upper limb force signals through force sensors and upper limb posture angle signals through posture sensors, and calculates the active assist value. The specific process is as follows:

[0028] The upper limb force signal is acquired by a force sensor and then filtered by a filtering model to obtain the following:

[0029]

[0030] in, Original hand interaction force (N). Interaction force after filtering, filter coefficients k is the discrete sampling number;

[0031] The upper limb posture angle signal is acquired by a posture sensor and then filtered by a filtering model to obtain:

[0032]

[0033] in, The original attitude angle, The filtered attitude angle, and the filter coefficients. k is the discrete sampling number;

[0034] Then, set the attitude angle after filtering. Given the upper limb lifting angle, the equivalent influence ratio of gravity on the lifting direction is calculated based on the current upper limb lifting angle, yielding the gravity component coefficient. :

[0035]

[0036] Based on filtered interaction force and gravitational component coefficient The equivalent load force model is established as follows:

[0037]

[0038] in, The equivalent load at the current moment, , These are calibration coefficients;

[0039] Establish an active-assisted target tension model:

[0040]

[0041] in, To proactively boost target tension, For flag position, To help the proportional coefficient, As the upper limit of tension, sat(x,0, ) is the amplitude limiting function;

[0042] Establish slope constraint models for soft start and soft loosening:

[0043] ;

[0044] in, The target tension after slope limitation at the sampling time; For the target tension that has not passed the slope limit at the sampling time, The target tension after slope limitation at the previous sampling time. , Slope limit (N / s) To control the cycle;

[0045] Then, establish an incremental PI control model:

[0046]

[0047] in, For motor output, sat(x) ) is the amplitude limiting function. This is the motor output from the previous moment. For the control error at the sampling time, This represents the control error at the previous sampling time. This is the proportional gain of the controller. The integral coefficient of the controller. This is the closed-loop control cycle. These are the maximum and minimum limits for the motor;

[0048] The controller outputs according to the incremental PI control model. Output electrical signal to drive motor to adjust torque, thus reducing the original hand interaction force. Gradually approaching the target tension after slope constraint This enables closed-loop control. Attached Figure Description

[0049] To make the objectives, technical solutions, and advantages of the invention clearer, the invention will now be described in further detail with reference to the accompanying drawings, wherein:

[0050] Figure 1 This is a front view of the present invention;

[0051] Figure 2 This is a schematic diagram of the clutch box of the present invention;

[0052] Figure 3 This is a schematic diagram of the operating mechanism of the present invention;

[0053] Figure 4 This is a schematic diagram of the passive energy storage mechanism of the present invention;

[0054] Figure 5 This is a schematic diagram of the adjustment belt of the present invention;

[0055] Figure 6 This is a schematic diagram of the positioning post of the present invention;

[0056] Figure 7 This is a schematic diagram of the rear side of the present invention;

[0057] Figure 8 This is a schematic diagram of the controller of the present invention;

[0058] Figure 9 This is a schematic diagram of the active assist mechanism of the present invention;

[0059] Figure 10 This is a flowchart of the present invention.

[0060] 1. Waist belt; 2. Back strap; 3. Arm belt; 4. Support rod; 5. Clutch box; 6. Operating mechanism; 7. Passive energy storage mechanism; 8. Active assist mechanism; 9. Lever arm ring; 10. Arm connecting rod; 11. Winding reel; 12. First winding groove; 13. Second winding groove; 14. Through hole; 15. Linkage shaft; 16. Sliding key; 17. First keyway; 18. Second keyway; 19. Threaded post; 20. Third keyway; 21. Lower fixing component; 22. Ball head; 23. Base; 24. Upper fixing component; 25. Support arm; 26. Mounting groove; 27. Adjusting belt; 28. Positioning hole; 29. ​​Mounting cylinder; 30. Positioning post; 31. Second spring; 32. Handle; 33. Connecting rod; 34. Bearing;

[0061] 601. Connector; 602. Cam; 603. Rotating pin; 604. Connecting hole;

[0062] 701. Sliding component; 702. First spring; 703. Cable; 704. Fixed pulley;

[0063] 801. Housing; 802. Motor; 803. Drive wheel; 804. Flange; 805. Bowden wire; 806. Battery; 807. Controller. Detailed Implementation

[0064] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0065] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, not all of them. Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to represent selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0066] It should be noted that similar reference numerals and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures. In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the figures, or the orientation or positional relationship commonly used when the product is in use. They are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first," "second," and "third," etc., are only used to distinguish descriptions and should not be construed as indicating or implying relative importance. In addition, the terms "horizontal," "vertical," etc., do not indicate that the component is required to be absolutely horizontal or suspended, but can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal than "vertical," and does not mean that the structure must be completely horizontal, but can be slightly tilted. In the description of this invention, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0067] Example 1

[0068] See Figure 1 and Figure 2 An active-passive fusion upper limb exoskeleton includes a waist belt 1, a back strap 2, and two sets of arm straps 3. The back strap 2 and waist belt 1 are fixedly connected, and the two arm straps 3 are located on the left and right sides of the back strap 2, respectively. The waist belt 1 is also provided with two support rods 4 on the left and right sides. The lower ends of the two support rods 4 are hinged to the waist belt 1, and the upper ends of the two support rods 4 are fixedly provided with a clutch box 5. The bottom of the clutch box 5 is an open structure. Inside the clutch box 5, there is a lever arm ring 9 and a winding reel 11. The lever arm ring 9 and the winding reel 11 are rotatably connected to the inner walls of the opposite sides of the clutch box 5 through bearings 34, respectively. A large arm connecting rod 10 is fixed on the lever arm ring 9. The end of the large arm connecting rod 10 away from the lever arm ring 9 extends from the bottom of the clutch box 5 and is connected to the arm straps 3. The outer peripheral wall of the winding reel 11 is provided with a first winding groove 12 and a second winding groove 13.

[0069] The clutch box 5 also has a linkage shaft 15. One end of the linkage shaft 15 is connected to an operating mechanism 6, and the other end extends into the clutch box 5 and passes through the winding reel 11 and the lever arm ring 9 in sequence. A sliding key 16 is provided on the outer wall of the linkage shaft 15 along its axial direction. A first keyway 17 is formed on the inner side of the winding reel 11 along the axial direction of the linkage shaft 15, and a second keyway 18 is formed on the inner side of the lever arm ring 9 along the axial direction of the linkage shaft 15. The operating mechanism 6 can drive the linkage shaft 15 to slide back and forth along its axial direction. In the initial state, the sliding key 16 and the lever arm ring 9 are in a separated state. When the operating mechanism 6 drives the linkage shaft 15 to move, the sliding key 16 on the linkage shaft can enter the first keyway 17 and the second keyway 18, so that the winding reel 11 and the lever arm ring 9 are connected.

[0070] The support rod 4 is a hollow rod body, and a passive energy storage mechanism 7 is provided inside it. The passive energy storage mechanism 7 is connected to one end of a cable, and the other end of the cable is wound in the first winding groove 12 and fixedly connected to the winding reel 11. An active assist mechanism 8 is provided on the rear side of the belt 1. The active assist mechanism 8 is provided with a Bowden wire. One end of the active assist mechanism 8 is connected to the Bowden wire, and the other end of the Bowden wire is wound in the second winding groove 13 and connected to the winding reel 11.

[0071] In this embodiment, the orientation of the operator wearing the exoskeleton is taken as the reference, with the chest and abdomen as the front, the two arms as the left and right sides, and the back as the rear.

[0072] The winding reel 11 includes a body and a protruding ring along its axial direction, the protruding ring facing away from the lever arm ring 9. The outer wall of the protruding ring is connected to the inner ring of a bearing 34, and the outer ring of the bearing 34 is connected to the side wall of the clutch box 5 on the same side. The lever arm ring 9 includes a body and a protruding ring along its axial direction, the protruding ring facing away from the winding reel 11. The outer wall of the protruding ring is connected to the inner ring of another bearing 34, and the outer ring of the bearing 34 is connected to the side wall of the clutch box 5 on the same side. The end of the linkage shaft 15 is located inside the protruding ring and the lever arm ring 9 as it passes through the winding reel 11 and the lever arm ring 9.

[0073] This exoskeleton has three modes: no assistance mode, passive assistance mode, and active-passive combined assistance mode.

[0074] During non-operational periods, the linkage shaft 15 is driven by the operating mechanism 6 to slide away from the lever arm ring 9, causing the slide key 16 to disengage from the second keyway 18, but the slide key 16 will still be located in the first keyway 17; at this time, the winding disc 11 is separated from the lever arm ring 9, which is the unassisted mode; the winding disc 11 and the linkage shaft 15 are stationary, while the lever arm ring 9 and the boom connecting rod 10 rotate freely in the clutch box 5, allowing the operator to swing their arm freely.

[0075] During operation, the linkage shaft 15 needs to be slid towards the lever arm ring 9, so that the sliding key 16 is simultaneously located in the first keyway 17 and the second keyway 18, and the winding reel 11 is connected to the lever arm ring 9. At this time, it is in passive assistance mode. When the operator swings the arm downward, it drives the boom linkage 10 to move, the boom linkage 10 drives the lever arm ring 9 to rotate, and the lever arm ring 9 drives the winding reel 11 and the linkage shaft 15 to rotate together. The winding reel 11 winds up the cable, and the passive energy storage mechanism 7 passively stores kinetic energy. When the operator needs to lift the arm upward to lift an object, the passive energy storage mechanism 7 provides assistance to better lift the heavy object.

[0076] Based on the passive assistance mode, the active assistance mechanism 8 can be activated as needed to provide adjustable secondary assistance, forming a superposition of active and passive assistance.

[0077] Compared to conventional active exoskeletons, this exoskeleton's active assist mechanism 8 can be activated periodically and intermittently, effectively extending its battery life and reducing energy dependence. Even after a power outage, the passive energy storage mechanism 7 still provides basic assistance. Compared to conventional passive exoskeletons, this exoskeleton can adjust the assist level through the active assist mechanism 8, preventing insufficient assistance from failing to effectively alleviate fatigue or excessive assistance from causing movement limitations and physical injury.

[0078] like Figure 2 and Figure 3 As shown, the operating mechanism 6 includes a connector 601 and a cam 602; one end of the linkage shaft 15 extending out of the side wall of the clutch box 5 is detachably connected to the connector 601; the connector 601 is rotatably connected to the cam 602 through a rotating pin 603, the outer contour of the cam 602 abuts against the outer wall of the clutch box 5, and can drive the linkage shaft 15 to slide along its axial direction.

[0079] In this embodiment, when it is necessary to drive the linkage shaft 15 to slide in the direction of the lever arm ring 9, the linkage shaft 15 is pushed into the clutch box 5 by manually pressing the end of the linkage shaft 15.

[0080] The outer contour of cam 602 includes multiple arc-shaped segments with different curvatures. A lug for actuation is fixed on cam 602. When it is necessary to drive the linkage shaft 15 to slide away from the lever arm ring 9, the position of the outer contour of cam 602 abutting against the outer wall of clutch box 5 is changed by actuating the lug. Due to the different contact positions of its different arc-shaped segments, the rotation axis of cam 602 and the outer wall of clutch box 5 are relatively displaced. Since clutch box 5 is fixed and cannot move, the linkage shaft 15 is pulled out. The structure is simple and easy to operate. The manual operation structure can minimize the size and weight of the mechanism.

[0081] like Figure 3As shown, a threaded post 19 is fixedly provided at one end of the linkage shaft 15 that is connected to the connector 601. The threaded post 19 is coaxial with the linkage shaft 15. A connecting hole 604 is provided at one end of the connector 601 facing the linkage shaft 15. The connecting hole 604 is threadedly connected to the threaded post 19.

[0082] In this embodiment, the linkage shaft 15 is connected to the connector 601 via the threaded post 19, which facilitates disassembly and replacement; it reduces the number of features of a single part, making it easier to process; in addition, the starting position of the linkage shaft 15 when sliding in the through hole 14 can be changed by changing the depth of the threaded post 19 screwed into the connecting hole 604.

[0083] like Figure 2 As shown, the clutch box 5 has a through hole 14 on one side wall through which the linkage shaft 15 passes. A third keyway 20 is formed on the inner side of the through hole 14 along the axial direction of the linkage shaft 15. When the linkage shaft 15 slides away from the lever arm ring 9, the sliding key 16 of the linkage shaft disengages from the second keyway 18 and enters the first keyway 17 and the third keyway 20.

[0084] In this embodiment, regardless of whether the linkage shaft 15 slides towards the lever arm ring 9 or in the opposite direction, the slide key 16 is always located in the first keyway 17.

[0085] When one end of the sliding key 16 enters the second keyway 18, the other end will disengage from the third keyway 20, and the lever arm ring 9 and the winding disc 11 will be connected, so that the lever arm ring 9 can drive the winding disc 11 and the linkage shaft 15 to rotate together.

[0086] When one end of the sliding key 16 disengages from the second keyway 18, the other end enters the third keyway 20. At this time, the lever arm ring 9 can rotate freely. Meanwhile, since the clutch box 5 is fixed and cannot move, the linkage shaft 15 cannot rotate within the through hole 14, thereby restricting the rotation of the linkage shaft 15 and the winding disc 11. This makes it easier to determine the angular position of the winding disc 11 and facilitates the subsequent re-establishment of the power connection.

[0087] like Figure 4 As shown, the lower ends of the two support rods 4 are fixed with lower fixing members 21, the lower end of the lower fixing member 21 is a ball head 22, and the left and right sides of the belt 1 are respectively provided with a base 23. The ball head 22 rotates and is located in the base 23, forming a ball hinge. The upper end of the support rod 4 is fixed with an upper fixing member 24, which is fixedly connected to the clutch box 5 through two support arms 25.

[0088] In this embodiment, the ball joint allows the shoulder position where the clutch box 5 is located and the arm position where the arm strap 3 is located to rotate freely, improving the flexibility and comfort of use.

[0089] Two end caps are fixedly provided on the inner walls of opposite sides of the clutch box 5. Two bearings 34 are rotatably installed inside the end caps. The side walls of the end caps are fixedly connected to the upper end of the support arm 25, and the lower end of the support arm 25 is fixedly connected to the upper fixing member 24.

[0090] like Figure 4 As shown, the passive energy storage mechanism 7 includes a sliding member 701, a first spring 702, a cable 703, and a fixed pulley 704; the top surface of the upper fixing member 24 has an installation groove 26, and the fixed pulley 704 is installed in the installation groove 26; the sliding member 701 is slidably located in the support rod 4, and the first spring 702 is located between the top surface of the sliding member 701 and the bottom surface of the upper fixing member 24; one end of the cable 703 is fixedly connected to the sliding member 701, and the other end passes through the upper fixing member 24, extends into the installation groove 26, passes around the fixed pulley 704, and extends into the clutch box 5 to connect with the winding reel 11.

[0091] In this embodiment, when the winding reel 11 and the lever arm ring 9 are connected by power, the operator swings the arm downward and drives the boom link 10. The boom link 10 drives the power arm ring 9 to rotate, and the lever arm ring 9 drives the linkage shaft 15 and the winding reel 11 to rotate. The winding reel 11 drives the cable 703, and the cable 703 pulls the sliding member 701 upward, thereby compressing the first spring 702 to store kinetic energy. The structure is simple because it relies on the passive energy storage of the spring. When the operator raises the arm upward, the elastic potential energy of the first spring 702 is released, which helps the operator raise the arm and reduces muscle fatigue and labor intensity.

[0092] As a parallel technical solution in this embodiment, the passive energy storage mechanism 7 can also be an elastic element such as a coil spring or a tension spring; one end of the elastic element is fixedly installed in the support rod 4, and the other end is a movable end and fixedly connected to the cable 703; the end of the cable 703 away from the elastic element extends out of the support rod 4 and extends into the clutch box 5 to connect with the winding reel 11.

[0093] like Figure 5 and Figure 6 As shown, two adjustment belts 27 are fixedly provided on the left and right sides of the waist belt 1. Several positioning holes 28 are opened on the adjustment belts 27 along the length direction of the waist belt 1. The base 23 is slidably installed on the adjustment belts 27. An installation cylinder 29 is also fixedly provided on the base 23. The installation cylinder 29 is open on one side facing the adjustment belts 27. A positioning post 30 is slidably provided inside it. A second spring 31 is provided between the bottom of the installation cylinder 29 and the positioning post 30. The second spring 31 is used to push the positioning post 30 to slide out from the open side of the installation cylinder 29 and into the positioning hole 28. A handle 32 is also provided at the end of the installation cylinder 29 away from the adjustment belts 27. A connecting rod 33 is fixedly provided on the handle 32. The connecting rod 33 passes through the bottom of the installation cylinder 29 and extends into the installation cylinder 29, and is detachably connected to the positioning post 30.

[0094] In this embodiment, when it is necessary to move the position of the base 23 on the adjusting belt 27, pull its handle 32. The handle 32 drives the positioning column 30 through the connecting rod 33. The positioning column 30 retracts into the mounting cylinder 29, the second spring 31 is compressed, and the base 23 can move.

[0095] Then, after the base 23 is moved to the appropriate position, the handle 32 is released, the second spring 31 is released, and the positioning column 30 is pushed into the positioning hole 28 at the position for fixation; the sliding base 23 can adjust the connection position between the support rod 4 and the waist belt 1 to adapt to workers of different body shapes and shoulder widths, and improve the versatility of the exoskeleton.

[0096] like Figures 7 to 9 As shown, the active assist mechanism 8 includes a housing 801, which is fixed to the rear side of the belt 1. Inside the housing 801 are two sets of motors 802, each corresponding to a clutch box 5. Each of the output shafts of the two motors 802 is equipped with a drive wheel 803. A Bowden wire 805 is wound around the drive wheel 803, and one end of the Bowden wire 805 is fixedly connected to the drive wheel 803. The other end of the Bowden wire 805 extends into the clutch box 5 and is connected to the winding reel 11. The housing 801 is also equipped with a battery 806 and a controller 807. The controller 807 is electrically connected to the two motors 802 through an interface. The battery 806 is electrically connected to the motors 802 and the controller 807 to supply power to the motors 802 and the controller 807.

[0097] In this embodiment, two motors 802 drive two drive wheels 803 to rotate. A flange 804 is also provided on each drive wheel 803. The flange 804 is used to fix and wind up the Bowden cable 805. The Bowden cable 805 drives the winding reels 11 on both shoulders to rotate, providing corresponding assistance. This can be controlled according to the actual load conditions, providing appropriate auxiliary support, thereby effectively reducing the burden on the shoulders and upper limb muscles of the operator and improving comfort and stability during long-term overhead operations.

[0098] like Figures 7 to 9 As shown, the active assist mechanism 8 also includes an attitude sensor and a force sensor, which are mounted on the arm belt 3 and electrically connected to the controller 807.

[0099] In this embodiment, it is convenient to monitor its attitude data and load data in real time, which facilitates real-time adjustment and provides better assistance support.

[0100] Example 2

[0101] like Figure 10 As shown, the present invention also provides a control method using the above-mentioned active-passive fusion upper limb exoskeleton, the specific steps of which are as follows:

[0102] 1. When the operator does not need assistance, slide the linkage axis away from the lever arm ring to disengage the winding disc from the lever arm ring, so that the boom connecting rod has no power intervention and can rotate freely;

[0103] 2. When assistance is required, slide the linkage axis towards the lever arm ring to connect the winding disc and the lever arm ring; the passive energy storage mechanism continuously provides assistance, while the active assistance mechanism can be activated as needed by the user.

[0104] III. When the active assist mechanism is activated, the active assist mechanism and the passive energy storage mechanism can work together to provide assistance. During this process, the controller acquires the upper limb force signal through the force sensor and the upper limb posture angle signal through the posture sensor, and calculates the active assist value. The specific process is as follows:

[0105] The upper limb force signal is acquired by a force sensor and then filtered by a filtering model to obtain the following:

[0106]

[0107] in, Original hand interaction force (N). Interaction force after filtering, filter coefficients k is the discrete sampling number;

[0108] Specifically, k represents the current signal sampling time (e.g., k=1, 2, 3..., corresponding to different time points of continuous sampling); The interaction force (i.e., historical data) has been filtered at the previous time step (k-1th sampling). These are the filter coefficients, ranging from 0 to 1. The closer to 1, the smoother the filtered signal (but the slower the response). The closer the signal is to 0, the closer it is to the original value (but the worse the noise suppression effect).

[0109] Then, the upper limb posture angle signal is acquired through the posture sensor and filtered by the filtering model to obtain:

[0110]

[0111] in, The original attitude angle, The filtered attitude angle, and the filter coefficients. k is the discrete sampling number;

[0112] Specifically, attitude angle The unit is radians. The lifting angle after filtering at the previous sampling time (i.e., historical data); These are the filter coefficients, ranging from 0 to 1, and their functions are... Consistent;

[0113] Then, set the attitude angle after filtering. Given the upper limb lifting angle, calculate the equivalent influence ratio of gravity on the lifting direction based on the current upper limb lifting angle, and establish a gravity component coefficient model:

[0114]

[0115] in, This is the coefficient for the gravitational component;

[0116] Then, based on the filtered interaction force and gravitational component coefficient The equivalent load force model is established as follows:

[0117]

[0118] in, The equivalent load at the current moment, , These are calibration coefficients;

[0119] Next, define the flags for the assist mode:

[0120] m(k) =

[0121] Among them, when When m=1; when When m=0; F1 is the equivalent load trigger threshold for entering the active-passive superimposed assist mode; F2 is the equivalent load release threshold for exiting the active-passive superimposed assist mode, and F1>F2 to form a hysteresis interval, t1 and t2 are the minimum duration required for the corresponding mode switching; it can reduce the frequent mode switching caused by accidental load fluctuations and reduce the switching frequency.

[0122] Then, establish an active-assisted target tension model:

[0123]

[0124] in, To proactively boost target tension, For flag position, To help the proportional coefficient, As the upper limit of tension, sat(x,0, ) is the amplitude limiting function;

[0125] Establish slope constraint models for soft start and soft loosening:

[0126] ;

[0127] in, The target tension after slope limitation at the sampling time; For the target tension that has not passed the slope limit at the sampling time, The target tension after slope limitation at the previous sampling time. , Slope limit (N / s) To control the cycle;

[0128] Specifically, The ascent slope limit represents the maximum rate of ascent allowed by the target tension. The descent slope limit represents the maximum descent rate allowed by the target tension; soft start and soft release are used to avoid sudden changes in target tension, achieving soft start (gradually increasing assistance) and soft release (gradually decreasing assistance), thus improving smoothness and safety;

[0129] Then, based on Establish a motor control error model:

[0130] ;

[0131] in, Control error at sampling time;

[0132] Then, establish an incremental PI control model:

[0133]

[0134] in, Sat(x, ) represents the motor output at the sampling time. ) is the amplitude limiting function. This represents the motor output at the previous sampling time. For the control error at the sampling time, This is the difference in control error from the previous sampling time. This is the proportional gain of the controller. The integral coefficient of the controller. This is the closed-loop control cycle. These are the maximum and minimum limits for the motor;

[0135] The controller outputs according to the incremental PI control model. Output electrical signal to drive motor to adjust torque, thus reducing the original hand interaction force. Gradually approaching the target tension after slope constraint To achieve closed-loop control; when the equivalent load force Once the load exceeds the preset threshold F1 and the duration reaches the preset time, it enters the active / passive superimposed assist mode; when the equivalent load force If the value is less than the preset threshold F2 and the duration reaches the preset time, exit the active / passive superimposed assist mode; return to passive assist mode, and the lifting task is completed.

[0136] This control method, through continuous sampling, error calculation, and closed-loop adjustment, enables the system to achieve stable control and real-time adjustment of the assist while ensuring output smoothness and safety. This allows for the combined assistance of the active assist mechanism and the passive energy storage mechanism, thereby reducing the workload of operators, improving work efficiency, and reducing fatigue.

[0137] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit the technical solutions. Those skilled in the art should understand that any modifications or equivalent substitutions to the technical solutions of the present invention without departing from the spirit and scope of the present invention should be covered within the scope of the claims of the present invention.

Claims

1. An active-passive fusion upper limb exoskeleton, comprising a waist belt (1), a back strap (2), and two sets of arm straps (3), wherein, The back strap (2) and waist belt (1) are fixedly connected, and the two arm straps (3) are located on the left and right sides of the back strap (2); the waist belt (1) is characterized by having two support rods (4) on the left and right sides, the lower ends of the two support rods (4) being hinged to the waist belt (1), and the upper ends of the two support rods (4) being fixedly provided with a clutch box (5); the bottom of the clutch box (5) is an open structure, and a lever ring (9) and a winding disc (11) are provided inside the clutch box (5). The lever ring (9) and the winding disc (11) are rotatably connected to the inner walls of the clutch box (5) on opposite sides through bearings. A large arm connecting rod (10) is fixed on the lever ring (9). The end of the large arm connecting rod (10) away from the lever ring (9) extends from the bottom of the clutch box (5) and is connected to the arm strap (3). A first winding groove (12) and a second winding groove (13) are provided on the outer peripheral wall of the winding disc (11). The clutch box (5) also has a linkage shaft (15). One end of the linkage shaft (15) is connected to an operating mechanism (6), and the other end extends into the clutch box (5) and passes through the winding disc (11) and the lever arm ring (9) in sequence. A sliding key (16) is provided on the outer wall of the linkage shaft (15) along its axial direction. A first keyway (17) is opened on the inner side of the winding disc (11) along the axial direction of the linkage shaft (15), and a second keyway (18) is opened on the inner side of the lever arm ring (9) along the axial direction of the linkage shaft (15). The operating mechanism (6) can drive the linkage shaft (15) to slide back and forth along its axial direction. In the initial state, the sliding key (16) and the lever arm ring (9) are in a separated state. When the operating mechanism (6) drives the linkage shaft (15) to move, the sliding key (16) on the linkage shaft can enter the first keyway (17) and the second keyway (18), so that the winding disc (11) and the lever arm ring (9) are connected. The support rod (4) is a hollow rod body with a passive energy storage mechanism (7) inside. The passive energy storage mechanism (7) is connected to one end of a cable, and the other end of the cable is wound in the first winding groove (12) and fixedly connected to the winding reel (11). The belt (1) is provided with an active assist mechanism (8) on the rear side. The active assist mechanism (8) is provided with a Bowden wire. The active assist mechanism (8) is connected to one end of the Bowden wire, and the other end of the Bowden wire is wound in the second winding groove (13) and connected to the winding reel (11).

2. The active-passive fusion upper limb exoskeleton according to claim 1, characterized in that, The operating mechanism (6) includes a connector (601) and a cam (602); the end of the linkage shaft (15) extending out of the side wall of the clutch box (5) is detachably connected to the connector (601); the connector (601) is rotatably connected to the cam (602) through a rotating pin (603), the outer contour of the cam (602) abuts against the outer wall of the clutch box (5), and can drive the linkage shaft (15) to slide along its axial direction.

3. The active-passive fusion upper limb exoskeleton according to claim 2, characterized in that, A threaded post (19) is fixedly provided at one end of the linkage shaft (15) connected to the connector (601). The threaded post (19) is coaxial with the linkage shaft (15). A connecting hole (604) is opened at one end of the connector (601) facing the linkage shaft (15). The connecting hole (604) is threadedly connected to the threaded post (19).

4. The active-passive fusion upper limb exoskeleton according to claim 3, characterized in that, The clutch box (5) has a through hole (14) on one side wall through which the linkage shaft (15) passes. A third keyway (20) is opened on the inner side of the through hole (14) along the axial direction of the linkage shaft (15). When the linkage shaft (15) slides away from the lever arm ring (9), the sliding key (16) of the linkage shaft disengages from the second keyway (18) and enters the first keyway (17) and the third keyway (20).

5. The active-passive fusion upper limb exoskeleton according to claim 1, characterized in that, The lower ends of the two support rods (4) are fixed with lower fixing members (21), the lower end of the lower fixing member (21) is a ball head (22), and the waist belt (1) is provided with a base (23) on the left and right sides respectively. The ball head (22) rotates and is located in the base (23) and forms a ball hinge. The upper end of the support rod (4) is fixed with an upper fixing member (24), which is fixedly connected to the clutch box (5) through two support arms (25).

6. The active-passive fusion upper limb exoskeleton according to claim 5, characterized in that, The passive energy storage mechanism (7) includes a sliding member (701), a first spring (702), a cable (703), and a fixed pulley (704); the top surface of the upper fixing member (24) has an installation groove (26), and the fixed pulley (704) is installed in the installation groove (26); the sliding member (701) slides in the support rod (4), and the first spring (702) is located between the top surface of the sliding member (701) and the bottom surface of the upper fixing member (24); one end of the cable (703) is fixedly connected to the sliding member (701), and the other end passes through the upper fixing member (24), extends into the installation groove (26), passes around the fixed pulley (704), and extends into the clutch box (5) to connect with the winding disc (11).

7. The active-passive fusion upper limb exoskeleton according to claim 5, characterized in that, The waist belt (1) has adjustment belts (27) at both ends. Several positioning holes (28) are provided on the adjustment belts (27) along the length of the waist belt (1). The base (23) is slidably installed on the adjustment belts (27). An installation cylinder (29) is also fixedly installed on the base (23). The installation cylinder (29) is open on one side facing the adjustment belts (27). A positioning post (30) is slidably installed inside it. A second spring (31) is provided between the bottom of the installation cylinder (29) and the positioning post (30) to push the positioning post (30) to slide out from the open side of the installation cylinder (29) and into the positioning hole (28). A handle (32) is also provided at the end of the installation cylinder (29) away from the adjustment belts (27). A connecting rod (33) is fixedly installed on the handle (32). The connecting rod (33) passes through the bottom of the installation cylinder (29) and extends into the installation cylinder (29), and is detachably connected to the positioning post (30).

8. The active-passive fusion upper limb exoskeleton according to claim 1, characterized in that, The active assist mechanism (8) includes a housing (801), which is fixed to the back of the belt (1). Inside the housing are two sets of motors (802) corresponding to the two clutch boxes (5). The output shafts of the two motors (802) are equipped with drive wheels (803). A Bowden wire (805) is wound on the drive wheel (803). One end of the Bowden wire (805) is fixedly connected to the drive wheel (803), and the other end of the Bowden wire (805) extends into the clutch box (5) and is connected to the winding disc (11). The housing (801) is also equipped with a battery (806) and a controller (807). The controller (807) is electrically connected to the two motors (802) through an interface. The battery (806) is electrically connected to the motors (802) and the controller (807) to supply power to the motors (802) and the controller (807).

9. The active-passive fusion upper limb exoskeleton according to claim 8, characterized in that, The active assist mechanism (8) also includes an attitude sensor and a force sensor, which are mounted on the armband (3) and electrically connected to the controller (807).

10. A control method, characterized in that, The specific steps for using the active-passive fusion upper limb exoskeleton as described in claim 9 are as follows: When the active assist mechanism is activated, the controller acquires upper limb force signals through force sensors and upper limb posture angle signals through posture sensors, and calculates the active assist value. The specific process is as follows: The upper limb force signal is acquired by a force sensor and then filtered by a filtering model to obtain the following: in, Original hand interaction force (N). Interaction force after filtering, filter coefficients k is the discrete sampling number; The upper limb posture angle signal is acquired by a posture sensor and then filtered by a filtering model to obtain: in, The original attitude angle, The filtered attitude angle, and the filter coefficients. k is the discrete sampling number; Then, set the attitude angle after filtering. Given the upper limb lifting angle, the equivalent influence ratio of gravity on the lifting direction is calculated based on the current upper limb lifting angle, yielding the gravity component coefficient. : Based on filtered interaction force and gravitational component coefficient The equivalent load force model is established as follows: in, The equivalent load at the current moment, , These are calibration coefficients; Establish an active-assisted target tension model: in, To proactively boost target tension, For flag position, To help the proportional coefficient, As the upper limit of tension, sat(x,0, ) is the amplitude limiting function; Establish slope constraint models for soft start and soft loosening: ； in, The target tension after slope limitation at the sampling time; For the target tension that has not passed the slope limit at the sampling time, The target tension after slope limitation at the previous sampling time. , Slope limit (N / s) To control the cycle; Then, establish an incremental PI control model: in, For motor output, sat(x) ) is the amplitude limiting function. This is the motor output from the previous moment. For the control error at the sampling time, This represents the control error at the previous sampling time. This is the proportional gain of the controller. The integral coefficient of the controller. This is the closed-loop control cycle. These are the maximum and minimum limits for the motor; The controller outputs according to the incremental PI control model. Output electrical signal to drive motor to adjust torque, thus reducing the original hand interaction force. Gradually approaching the target tension after slope constraint This enables closed-loop control.

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