Upper limb support exoskeleton based on negative pressure occlusion variable stiffness driver

Abstract

The application discloses an upper limb supporting exoskeleton based on a negative pressure occlusion variable stiffness driver, which comprises a shoulder joint supporting structure, an elbow joint supporting structure connected with the shoulder joint supporting structure, a waist belt and a back strap; the waist belt and the back strap form a backpack type structure, and the shoulder joint supporting structure is fixed on the shoulder and back of a human body; the shoulder joint supporting structure is connected with the elbow joint supporting supporting structure through a large arm guide rail sliding block and can slide relatively to meet the wearers with different large arm lengths; a fixing plate for fixing the elbow joint supporting structure with the large arm and the small arm of the wearer is arranged on the elbow joint supporting structure. The upper limb supporting exoskeleton based on the negative pressure occlusion variable stiffness driver adopts the variable stiffness driver as part of the joints of the robot, guarantees sufficient degrees of freedom and supporting effect, improves the adaptability of the whole system, allows the wearers to change the stiffness of part of the joints according to the self needs and environmental conditions, and makes the activities of the wearers in the non-working state more flexible and the movement resistance smaller.

Description

Technical Field

[0001] This invention relates to the field of robotics, and in particular to an upper limb support exoskeleton based on a negative pressure bite variable stiffness actuator. Background Technology

[0002] With the development of science and technology, more and more repetitive and mechanical jobs have gradually become automated. However, some complex and specialized tasks still require humans to operate in fixed postures, such as overhead tasks on industrial assembly lines. These tasks often require workers to raise their arms at a certain angle and maintain a fixed posture for extended periods. Over time, this places a heavy burden on the workers' shoulder and elbow joints, potentially causing muscle fatigue and injury, thus threatening their health. Exoskeleton robots are a type of wearable robotic technology designed to enhance human physical functions and performance. Their main functions include assistive enhancement, reducing muscle fatigue and injury, rehabilitation therapy, and improving work efficiency.

[0003] Traditional exoskeleton robots, limited by their structure and operating methods, have certain limitations that affect the wearer's activities when not working, exhibiting poor adaptability. Furthermore, due to assembly errors in the rigid structure and wearing errors, traditional exoskeleton robots experience significant resistance and lack smooth movement. These issues greatly restrict the development and application of exoskeleton robots. Summary of the Invention

[0004] The purpose of this invention is to reduce muscle fatigue and injury in workers who perform long-term overhead tasks, and to meet the adaptive requirements of upper limb exoskeleton robots, it provides an upper limb support exoskeleton based on a negative pressure bite variable stiffness actuator, which is an upper limb support exoskeleton robot integrating a negative pressure bite variable stiffness actuator.

[0005] An upper limb support exoskeleton based on a negative pressure bite variable stiffness actuator includes a shoulder joint support structure and an elbow joint support structure connected thereto, a waist belt, and a back strap; the waist belt and back strap form a backpack-like structure to fix the shoulder joint support structure to the human shoulder and back; the shoulder joint support structure and the elbow joint support structure are connected by a large arm guide slider, which can slide relative to each other to accommodate wearers with different large arm lengths; the elbow joint support structure is provided with a fixing plate for fixing it to the wearer's large arm and forearm.

[0006] The shoulder joint support structure is fixed to the back of the human body via a waist belt and shoulder straps. It includes a T-shaped plate at the bottom, a back support plate connected to the T-shaped plate, a Bowden cable, a shoulder width adjustment block, a bending actuator, a back stretching actuator, an upper arm stretching actuator, and an upper arm bar. The shoulder width adjustment blocks are symmetrically installed on the horizontal part of the back support bar. The two ends of the bending actuator are connected and fixed to the shoulder width adjustment block and the upper arm bar respectively via bearings. One end of the back stretching actuator is fixed to a fixing pin installed at the bottom of the T-shaped plate, and the other end is anchored to a first steel wire rope. The first steel wire rope passes through the Bowden cable, wraps around the large side wheel of the bending actuator, and is anchored thereto, forming a first rotary joint. One end of the upper arm stretching actuator is fixed to the upper arm bar, and the other end is anchored to a second steel wire rope. The second steel wire rope wraps around the front pulley of the upper arm bar, and the other end wraps around the small side wheel of the bending actuator and is anchored thereto, forming a second rotary joint.

[0007] The shoulder width adjustment block is installed by inserting its own elastic pin into the hole of the back support plate to adjust the distance between the two shoulder width adjustment blocks; the two ends of the bending actuator are fixed to the shoulder width adjustment block and the upper arm of the elbow joint support structure by bearings and pins respectively.

[0008] The stretching actuator constituting the back stretching actuator and the upper arm stretching actuator includes a first tensile membrane, an elastic membrane, a silicone airbag, a first biting tooth, a first sponge strip, and a sealing end block. The first tensile membrane and the elastic membrane form a parallelogram structure. The first biting tooth and the first sponge strip are attached to the corresponding positions on the first tensile membrane and are located inside the parallelogram structure. The first biting teeth arranged opposite to each other on the upper and lower surfaces are staggered to achieve biting. The first sponge strip is attached to the gap or groove of the first biting teeth arranged opposite to each other on the upper and lower surfaces. The silicone airbag covers the outside of the parallelogram structure, and the two ends of the outside of the parallelogram structure are sealed by the sealing end block.

[0009] The bending actuator includes a central wheel assembly, a bite plate layer, and a TPU airbag. The central wheel assembly includes a center wheel and transition wheels arranged on both sides of the center wheel. Side wheels are arranged on the outer side of the transition wheels, and the transition wheels are connected to the bite portions of the side wheels. There are two side wheels, including a large side wheel and a small side wheel, arranged on the outer side of the transition wheels. They are circular wheels with grooves on their surfaces. The bite portions of the transition wheels, the center wheel, and the side wheels are connected by a rotating shaft. The bite plate layer engages with the teeth on the upper and lower surfaces of the bite portions of the transition wheels and the side wheels. The TPU airbag covers the outer side of the bite plate layer, and the side wheels are exposed outside the TPU airbag.

[0010] The bite layer includes a double-layered second tensile membrane, a second sponge strip, and a second bite tooth arranged vertically. The second bite tooth and the second sponge strip are pasted on the opposite surface between the two layers of the second tensile membrane and are arranged corresponding to the bite part of the transition wheel and the side wheel. The second sponge strip is arranged on the outer end of the second bite tooth, and its length direction is perpendicular to the length direction of the second bite tooth.

[0011] The center wheel, the transition wheel, and the side wheel engagement portion each have shaft connection holes on both sides along their length direction, and these holes are arranged in an alternating manner. The rotating shaft is installed in the shaft connection holes to connect the center wheel, the transition wheel, and the side wheel engagement portion.

[0012] The elbow joint support structure includes a forearm rod, a pressure plate, and a spring air bladder. The forearm rod and the boom rod are interference-fitted together via a thin-walled bearing. The two ends of the spring air bladder are connected to the forearm rod and the pressure plate, respectively. The boom rod has a stepped shaft perpendicular to its main body. The stepped shaft passes sequentially through the thin-walled bearing, the shaft hole of the forearm rod, the spring air bladder, and the pressure plate, assembling the boom rod, forearm rod, spring air bladder, and pressure plate together. The spring air bladder is located in the space formed by the pressure plate and the shaft hole. The thin-walled bearing is located in the lower part of the shaft hole, and its inner surface mates with the bottom outer circular surface of the stepped shaft of the boom rod. The pressure plate has a circular structure that mates with the protrusion of the shaft hole. The mating surfaces of the protrusion of the shaft hole and the pressure plate have meshing toothed groove structures.

[0013] The boom has a circular baffle at the end of the stepped shaft to prevent the pressure plate from falling off; the forearm has a forearm guide rail slider, and a C-shaped plate for connecting the forearm and fixed to the forearm is installed on the forearm guide rail slider; the boom has a C-shaped plate for connecting the boom, and at least one C-shaped plate for connecting the boom is bolted to the boom guide rail slider.

[0014] The fixing plate is a C-shaped plate.

[0015] In its inactive state, this invention enables the shoulder joint to perform flexion and extension movements in the sagittal plane, abduction and adduction movements in the coronal plane, abduction and adduction movements in the horizontal plane, and flexion and extension movements in the elbow joint. In its activated state, this invention provides effective support for the shoulder and elbow joints, relieving fatigue in the related muscles of the upper limb caused by maintaining a specific posture for a long time.

[0016] The variable stiffness tension actuator of this invention has a small initial tensile force under normal pressure, resulting in less resistance to joint movement in the wearer. The multi-link variable stiffness bending actuator of this invention can adapt to the movement deviation of the shoulder joint in the horizontal plane, improving the flexibility of normal upper limb activities.

[0017] The present invention designs an adjustment mechanism, including a shoulder width adjustment component on the back and a guide rail slider component on the upper arm, to meet the needs of wearers of different body types.

[0018] Except for the back support plate, connecting shaft, bearing, guide rail slider, connecting bolt, and other parts, the upper limb support exoskeleton of the present invention is made of carbon fiber plate or 3D printing. It has the advantages of being lightweight, easy to manufacture and low cost, which helps to reduce the total cost of exoskeleton robots and promotes large-scale use.

[0019] Compared with existing upper limb exoskeleton robots, the upper limb support exoskeleton based on negative pressure bite variable stiffness actuator of the present invention uses variable stiffness actuator as part of the robot's joints. While ensuring sufficient degrees of freedom and support effect, it improves the adaptability of the entire system, allowing the wearer to change the stiffness of some joints according to their own needs and environmental conditions, making the wearer's activities more flexible and with less movement resistance when not working. Attached Figure Description

[0020] Figure 1 A schematic diagram of the overall structure of the present invention is shown.

[0021] Figure 2 A schematic diagram of the shoulder joint support structure is shown.

[0022] Figure 3 A schematic diagram of the principle of rotary joint I and rotary joint II is shown.

[0023] Figure 4 An exploded structural diagram of the elbow joint support structure is shown.

[0024] Figure 5 A schematic diagram of the overall external structure of the elbow joint support structure is shown.

[0025] Figure 6 A schematic diagram of the overall external structure of the stretch actuator is shown.

[0026] Figure 7 The diagram shows the explosion of the stretching actuator and an enlarged structural schematic.

[0027] Figure 8 A schematic diagram of the front view structure of the stretch actuator is shown.

[0028] Figure 9 A schematic diagram of the exploded structure of the bending actuator is shown.

[0029] Figure 10 A schematic diagram of the exploded structure of a wheel assembly for a bending drive is shown.

[0030] Figure 11 A schematic diagram of the overall structure of the bending actuator is shown.

[0031] Figures 12-14 The diagrams show the motion of the upper limb supporting the exoskeleton in three orthogonal planes.

[0032] In the picture:

[0033] 1-Waist belt, 2-Elbow joint support structure, 3-C-shaped plate, 4-Back strap, 5-Upper arm guide slider, 6-Shoulder joint support structure, 7-T-shaped plate, 8-Fixing pin, 9-Back extension actuator, 10-Back support plate, 11-Shoulder width adjustment block, 12-Bowden cable, 13-Bend actuator, 14-Upper arm bar, 15-Upper arm extension actuator, 16-Windlock bar, 17-Wire rope, 18-Fixing rod, 19-Upper arm bar, 20-Thin-walled bearing, 2 1-Spring airbag, 22-Pressure plate, 23-Baffle plate, 24-Small arm rod, 25-Small arm guide rail slider, 26-First tensile membrane, 27-Sealing end block, 28-Elastic membrane, 29-Silicone airbag, 30-First engagement tooth, 31-First sponge strip, 32-Large side wheel, 33-Transition wheel, 34-Center wheel, 35-Small side wheel, 36-Second sponge strip, 37-Second tensile membrane, 38-Rotating shaft, 39-Second engagement tooth, 40-TPU airbag. Detailed Implementation

[0034] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

[0035] Variable stiffness actuators, being structures or systems capable of altering their own stiffness and adjusting their shape according to changes in environmental conditions, are widely used in robotics. Therefore, the applicant of this invention proposes a highly adaptive upper limb support exoskeleton integrating a variable stiffness actuator, which can provide new options for exoskeleton robot design and promote the development and widespread application of exoskeleton robots.

[0036] Reference Figure 1 As shown, the upper limb support exoskeleton of this embodiment includes a waist belt 1, an elbow joint support structure 2, a C-shaped plate 3, a back strap 4, an upper arm guide rail slider 5, and a shoulder joint support structure 6. The waist belt 1 and the back strap 4 form a backpack-like structure, and the shoulder joint support structure 6 is fixed to the human shoulder and back. The shoulder joint support structure 6 and the elbow joint support structure 2 are connected by the upper arm guide rail slider 5 and can slide relative to each other to meet the needs of wearers with different upper arm lengths. The C-shaped plate 3 is used to fix the overall structure on the upper arm and forearm.

[0037] refer to Figure 2As shown, in some embodiments, the shoulder joint support structure includes a T-shaped plate 7, a fixing pin 8, a back stretch actuator 9, a back support plate 10, a shoulder width adjustment block 11, a Bowden cable 12, a bending actuator 13, an upper arm bar 14, and a calf stretch actuator 15. There are two back stretch actuators 9, arranged symmetrically. There are two shoulder width adjustment blocks 11, arranged symmetrically. There are also two Bowden cables 12, two bending actuators 13, two upper arm bars 14, and two calf stretch actuators 15, arranged symmetrically.

[0038] In some implementations, the T-shaped plate 7 and the back support rod 10 are connected by bolts, and the fixing pin 8 is fixed to the upper part of the T-shaped plate 7 and the lower part of the back support rod 10. The back support rod 10 has a roughly T-shaped structure, and the T-shaped plate 7 is connected to its vertical part. The shoulder width adjustment block 11 is installed on the horizontal part of the back support rod 10, and its own elastic pin can be inserted into the mounting hole of the horizontal part of the back support plate 10 to realize the adjustment of the distance between the two shoulder width adjustment blocks 11.

[0039] In some embodiments, the bending actuator 13 is connected at both ends to the shoulder width adjusting block 11 and the upper arm rod 14 via bearings and pins, respectively, forming rotary joints. One end of the back extension actuator 9 is fixed to the fixed pin 8, and the other end is connected to the first steel wire rope. The first steel wire rope passes through the Bowden conduit 12, wraps around the large side wheel 32 of the bending actuator 13, and is anchored thereto, forming rotary joint I. One end of the upper arm extension actuator 15 is fixed inside the upper arm rod 14, and the other end is connected to the second steel wire rope, which passes through the front end of the upper arm rod 14 (…). Figure 1 , 2 The fixed pulley and hole (not shown at the right end) are wrapped around and anchored to the small side wheel 35 of the bending drive 13 to form a rotary joint II.

[0040] refer to Figure 3 As shown, Figure 3 The schematic diagrams of rotary joints I and II are shown, using steel wire rope 17 as an example. If the steel wire rope 17 is wound around and anchored to the winch rod 16 (such as a small or large spool), a tension actuator (such as a boom tension actuator or a back tension actuator) provides tension F to the steel wire rope, thereby generating a counterclockwise torque T between the fixed rod 18 (such as a spool fixed shaft) and the winch rod 16, and subsequently generating an upward supporting force FN at the end of the winch rod 16. In this invention, both rotary joints I and II provide torque to the rotational shaft through the tension passively generated by the tension actuator, thus locking the rotational degree of freedom.

[0041] Reference Figure 4 and Figure 5As shown, in some embodiments, the elbow joint support structure includes an upper arm rod 19, a thin-walled bearing 20, a spring airbag 21, a pressure plate 22, a baffle 23, a lower arm rod 24, and a lower arm guide slider 25. The boom 19 and the forearm 24 are respectively tightly fitted with the inner and outer rings of the thin-walled bearing 20. The upper and lower surfaces of the spring airbag 21 are respectively bonded to the plane A of the boom 19 and the pressure plate 22. The pressure plate 22 can only move axially along the groove on the stepped shaft of the boom 19. The baffle 23 is fixed to the end of the stepped shaft of the boom 19 by bolts to prevent the pressure plate 22 from falling off. The forearm 24 has a forearm guide rail slider 25. The C-shaped plate fixed to the forearm is installed on the forearm guide rail slider to realize the position adjustment. The boom is equipped with a boom connecting C-shaped plate. The boom connecting C-shaped plate is connected to the third C-shaped plate for connecting the boom installed on the boom guide rail slider 5. The third C-shaped plate is bolted to the boom connecting C-shaped plate.

[0042] Under normal pressure, the spring airbag 21 lifts the pressure plate 22, and the teeth on the pressure plate 22 disengage from the teeth on the forearm 24, allowing the boom 19 and the forearm 24 to rotate relative to each other. Under negative pressure, the spring airbag 21 contracts, and the teeth on the pressure plate 22 engage with the teeth on the forearm 24, locking the relative angle between the boom 19 and the forearm 24.

[0043] Reference Figure 6 and Figure 7 , Figure 8 As shown, in some embodiments, the tension actuators constituting the back tension actuator and the upper arm tension actuator have the same structure, including a first tensile membrane 26, a sealing end block 27, an elastic membrane 28, a silicone airbag 29, first interlocking teeth 30, and a first sponge strip 31. The first tensile membrane 26 and the elastic membrane 28 are bonded together to form a parallelogram structure, with the upper and lower long sides being the first tensile membrane and the left and right short sides being the elastic membrane. The first interlocking teeth 30 are bonded to both sides of the overlapping area of ​​the two layers of the first tensile membrane 26 and are arranged vertically and vertically, i.e., there are interlocking teeth on both the upper and lower surfaces, arranged alternately, to achieve interlocking. The first sponge strip 31 is bonded to the gaps or grooves of the first interlocking teeth 30. The sealing end block 27 is fitted onto and bonded to the first tensile membrane 26. The silicone airbag 29 covers the outside of the overall structure, i.e., it is wrapped around the outside of the parallelogram structure.

[0044] Under normal pressure, the first bite teeth 30 arranged vertically on both sides do not bite together under the support of the first sponge strip 31. The tension at both ends is transmitted through the elastic membrane 28 and the silicone air 29. The tension actuator is easily stretched and has low tensile stiffness. Under negative pressure, the first sponge strip 31 is compressed, causing the first bite teeth 30 arranged vertically on both sides to bite together. The tension at both ends is transmitted through the biting part of the first tensile membrane 26. The tension actuator is difficult to stretch and has high tensile stiffness.

[0045] Reference Figure 9 and Figure 10 , 11 As shown, in some embodiments, the bending actuator includes a large side wheel 32, a transition wheel 33, a center wheel 34, a small side wheel 35, a second sponge strip 36, a second tensile membrane 37, a rotating shaft 38, a second engagement tooth 39, and a TPU airbag 40; the large side wheel 32, small side wheel 35, transition wheel 33, and center wheel 34 are connected by the rotating shaft 38. Specifically, the small side wheel and the large side wheel each have a transitional engagement portion, the surface of the center wheel has no tooth grooves, and the transition wheel and the small side wheel and the large side wheel... The upper and lower surfaces of the meshing parts have toothed grooves. The connecting sides of the meshing parts of the center wheel, transition wheel, and small and large side wheels each have shaft connecting holes, which are staggered and connected by a rotating shaft 38 after docking. The second meshing teeth 39 are attached to the second tensile membrane 37, and their positions correspond to the toothed grooves of the wheel set. The second sponge strips 36 are attached to the second tensile membrane 37 and located at both ends of the second meshing teeth 39. They constitute a meshing sheet layer, which is centered and attached to both sides of the center wheel 34. The TPU airbag 40 covers the center wheel, transition wheel, and the meshing parts and meshing sheet layer of the small and large side wheels.

[0046] Under normal pressure, the second meshing tooth 39 does not mesh with the wheel set tooth groove due to the support of the second sponge strip 36, and the structure can bend freely with low bending resistance and low overall stiffness. Under negative pressure, the second meshing tooth 39 meshes with the wheel set tooth groove, and the overall structure is interlocked, resulting in high bending resistance and high overall stiffness.

[0047] refer to Figure 12 As shown, Figure 12 The exoskeleton's abduction and adduction movements in the coronal plane are shown, with the primary joint involved being rotary joint I. Under normal pressure, the tension of the tension actuator is relatively low, resulting in low rotational resistance in rotary joint I. Under negative pressure, the tension actuator engages internally, leading to greater tension resistance. This generates torque on rotary joint I via a steel cable, locking rotary joint I in one direction.

[0048] refer to Figure 13 As shown, Figure 13 The exoskeleton's abduction and adduction movements in the horizontal plane are shown, with the flexion actuator being the primary joint involved. Under normal pressure, no engagement occurs within the flexion actuator, resulting in low bending resistance; under negative pressure, engagement occurs within the flexion actuator, increasing overall stiffness and bending resistance, locking the shoulder joint's abduction and adduction movements in the horizontal plane.

[0049] refer to Figure 14 As shown, Figure 14The exoskeleton exhibits flexion and extension movements in the sagittal plane, with the primary joint involved being rotary joint II. Under normal pressure, the tension of the tension actuators is relatively low, resulting in low rotational resistance in rotary joint II. Under negative pressure, the tension actuators engage internally, leading to greater tension resistance. This generates torque on rotary joint II via a steel cable, locking it in one direction.

[0050] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. It will be apparent to those skilled in the art that the present invention is not limited to the details of the above exemplary embodiments, and that the present invention can be implemented in other specific forms without departing from the spirit or basic features of the present invention.

[0051] Therefore, the embodiments should be regarded as exemplary and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, it is intended that all variations falling within the meaning and scope of the equivalents of the claims be included within the invention.

[0052] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. An upper limb support exoskeleton based on a negative pressure occlusal variable stiffness actuator, characterized in that, It includes a shoulder joint support structure and an elbow joint support structure connected thereto, a waist belt and a back strap; the waist belt and back strap form a backpack-like structure to fix the shoulder joint support structure to the human shoulder and back; the shoulder joint support structure and the elbow joint support structure are connected by a large arm guide slider, which can slide relative to each other to meet the needs of wearers with different large arm lengths. The elbow joint support structure is equipped with a fixation plate for securing it to the wearer's upper arm and forearm; The shoulder joint support structure is fixed to the back of the human body by a waist belt and shoulder straps, including a T-shaped plate at the bottom, a back support plate connected to the T-shaped plate, a Bowden cable tube, a shoulder width adjustment block, a bending actuator, a back stretching actuator, an upper arm stretching actuator, and an upper arm bar; the shoulder width adjustment blocks are symmetrically installed on the horizontal part of the back support plate; the two ends of the bending actuator are connected and fixed to the shoulder width adjustment block and the upper arm bar respectively by bearings; one end of the back stretching actuator is fixed to a fixing pin installed at the bottom of the T-shaped plate, and the other end is anchored to a first steel wire rope; the first steel wire rope passes through the Bowden cable tube, goes around the large side wheel of the bending actuator and is anchored thereto, forming a first rotary joint; One end of the boom extension actuator is fixed to the upper boom rod, and the other end is anchored to the second steel wire rope; the second steel wire rope passes around the pulley at the front end of the upper boom rod, and the other end is wrapped around the small side wheel of the bending actuator and anchored thereto, forming a second rotary joint; The tension actuator constituting the back tension actuator and the upper arm tension actuator includes a first tensile membrane, an elastic membrane, a silicone airbag, first engagement teeth, a first sponge strip, and a sealing end block. The first tensile membrane and the elastic membrane form a parallelogram structure. The first engagement teeth and the first sponge strip are attached to corresponding positions on the first tensile membrane and are located within the parallelogram structure. The first engagement teeth, which are arranged opposite to each other on the upper and lower surfaces, are staggered to achieve engagement. The first sponge strip is attached to the gaps or grooves of the first engagement teeth arranged opposite to each other on the upper and lower surfaces. The silicone airbag covers the outside of the parallelogram structure, and the two ends of the outside of the parallelogram structure are sealed by the sealing end block. The bending actuator includes a central wheel assembly, a bite plate layer, and a TPU airbag. The central wheel assembly includes a center wheel and transition wheels arranged on both sides of the center wheel. Side wheels are arranged on the outer side of the transition wheels, and the transition wheels are connected to the bite portions of the side wheels. There are two side wheels, including a large side wheel and a small side wheel, arranged on the outer side of the transition wheels. They are circular wheels with grooves on their surfaces. The bite portions of the transition wheels, the center wheel, and the side wheels are connected by a rotating shaft. The bite plate layer engages with the teeth on the upper and lower surfaces of the bite portions of the transition wheels and the side wheels. The TPU airbag covers the outer side of the bite plate layer, and the side wheels are exposed outside the TPU airbag. The elbow joint support structure includes a forearm rod, a pressure plate, and a spring air bladder. The forearm rod and the boom rod are interference-fitted together via a thin-walled bearing. The two ends of the spring air bladder are connected to the forearm rod and the pressure plate, respectively. The boom rod has a stepped shaft perpendicular to its main body. The stepped shaft passes sequentially through the thin-walled bearing, the shaft hole of the forearm rod, the spring air bladder, and the pressure plate, assembling the boom rod, forearm rod, spring air bladder, and pressure plate together. The spring air bladder is located in the space formed by the pressure plate and the shaft hole. The thin-walled bearing is located in the lower part of the shaft hole, and its inner surface mates with the bottom outer circular surface of the stepped shaft of the boom rod. The pressure plate has a circular structure that mates with the protrusion of the shaft hole. The mating surfaces of the protrusion of the shaft hole and the pressure plate have meshing toothed groove structures.

2. The upper limb support exoskeleton based on negative pressure occlusal variable stiffness actuator according to claim 1, characterized in that, The shoulder width adjustment block is installed by inserting its own elastic pin into the hole in the back support plate to adjust the distance between the two shoulder width adjustment blocks; the two ends of the bending driver are fixed to the shoulder width adjustment block and the upper arm rod respectively by bearings and pins.

3. The upper limb support exoskeleton based on negative pressure occlusal variable stiffness actuator according to claim 1, characterized in that, The interlocking layer includes a double-layered second tensile membrane, a second sponge strip, and a second interlocking tooth arranged vertically. The second interlocking tooth and the second sponge strip are pasted on the opposite surface between the two layers of the second tensile membrane and are arranged corresponding to the interlocking part of the transition wheel and the side wheel. The second sponge strip is arranged on the outer end of the second interlocking tooth, and its length direction is perpendicular to the length direction of the second interlocking tooth.

4. The upper limb support exoskeleton based on negative pressure occlusal variable stiffness actuator according to claim 1, characterized in that, The center wheel, the transition wheel, and the side wheel engagement portion each have shaft connection holes on both sides along their length and are arranged in an alternating manner. The rotating shaft is installed in the shaft connection holes to connect the center wheel, the transition wheel, and the side wheel engagement portion.

5. The upper limb support exoskeleton based on negative pressure occlusal variable stiffness actuator according to claim 1, characterized in that, The end of the stepped shaft of the boom is provided with a circular baffle to prevent the pressure plate from falling off; the forearm has a forearm guide rail slider, and a forearm connecting C-shaped plate fixed to the forearm is installed on the forearm guide rail slider; the boom is equipped with a boom connecting C-shaped plate, and at least one boom connecting C-shaped plate is bolted to the boom guide rail slider.

6. The upper limb support exoskeleton based on negative pressure occlusal variable stiffness actuator according to claim 1, characterized in that, The fixing plate is a C-shaped plate.

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