Underactuated rigid-flexible hybrid exoskeleton based on origami-like variable stiffness support

Abstract

This invention provides an underactuated, hybrid rigid-flexible exoskeleton based on origami-style variable stiffness support, comprising: a lumbar support assembly, lateral drive units, thigh linkage assemblies, a central spinal support assembly, a coupling transmission mechanism, and a rigid back frame. The lumbar support assembly extends horizontally. Two sets of lateral drive units are symmetrically mounted on the left and right sides of the lumbar support assembly. The thigh linkage assembly is connected to the power output shaft of the lateral drive units and extends downward. The rigid back frame is located above the central spinal support assembly. The central spinal support assembly is flexibly connected between the lumbar support assembly and the rigid back frame. This application achieves effective reuse of the lateral motor power for the spinal support structure without increasing the number of additional drive units, resolves power source motion conflicts, realizes a time-sharing assist exoskeleton system, and achieves the effect of "time-sharing intervention" for hip and spinal assistance.

Description

Technical Field

[0001] This invention belongs to the technical field of skeletal robots and wearable assistive devices. Specifically, it relates to an underactuated rigid-flexible hybrid exoskeleton robot that utilizes a time-sharing coupling mechanism to achieve coordinated hip and spine assistance, and integrates upper limb gravity compensation function. Background Technology

[0002] With the increasing intensity of work in scenarios such as logistics handling, construction, and industrial manufacturing, workers are prone to lumbar and upper limb muscle fatigue, and may even suffer occupational injuries, due to frequent bending over, standing up, and prolonged arm raising.

[0003] Patent document CN109262594A discloses a hip joint structure for an assistive exoskeleton. By setting up a main waist structure and hip joint structures symmetrically arranged on both sides of the main waist structure, a motion connecting shaft is set in the double hole structure of the right waist structure and the hip joint adapter plate. The ends of the two motion connecting shafts are respectively fixed with a hip joint abduction and extension motion mechanism and a hip joint power mechanism. The hip joint abduction and extension motion mechanism and the hip joint power mechanism are connected as one unit by a connecting fastener. The lower end of the hip joint abduction and extension motion mechanism is provided with a thigh tube for connecting with the knee of the exoskeleton leg. This realizes a multi-degree-of-freedom rigid-flexible structure for the hip, knee and ankle joints, which can better fit the movement state of human joints.

[0004] Although leg exoskeletons have seen significant advancements, existing technologies like those in patent document CN109262594A cannot be effectively integrated with existing lumbar exoskeletons to achieve seamless coordination with the lumbar region. Current active lumbar assist exoskeletons primarily fall into two technical categories: I. Side-Motor Rigid Drive Exoskeleton: This type of exoskeleton typically has drive motors on both sides of the hip joint, using rigid linkages or support plates to assist in thigh flexion and extension, thereby providing assistance for the body's standing movements. This design is highly efficient in assisting the hip joint, but its back usually only has a passive rigid backplate or nothing at all, making it difficult to provide active and adaptable support to the spine's curvature.

[0005] II. Back-Driven Exoskeleton: This type of exoskeleton has an independent motor on the back of the body to drive the spinal support structure. While it can provide support for the spine, it adds an extra power source, resulting in a large overall weight and a complex system.

[0006] In recent years, rigid-flexible coupling exoskeletons have emerged that attempt to combine the two, mostly employing a "rigid synchronous coupling" method, where the hip and spinal structures are simultaneously stressed when the motor moves. However, this often faces the problem of kinematic incompatibility, as the extension speed of the hip joint and the straightening speed of the spine are not entirely consistent in different individuals or different movements. If a rigid cable is used for a direct connection, it is very easy to cause "speed conflict"—that is, the motor pulls too fast, causing back constriction, or pulls too slowly, causing lag in assistance. In addition, according to the "Lumbo-Pelvic Rhythm" in human biomechanics, during the process of the human body returning to an upright position from deep flexion (bending over), the extension of the hip joint and the extension of the spine are not completely linearly synchronized: In the early stage of the movement (deep flexion): the hip extension is mainly achieved by the gluteus maximus, and the spine should remain locked to reduce the lever arm of the weight; if the exoskeleton forcibly straightens the spine at this time, it will produce motion interference and a sense of resistance; in the middle and late stages of the movement: the load on the erector spinae muscles increases sharply, and at this time, spinal extension assistance is urgently needed, which traditional synchronous drive cannot meet.

[0007] In summary, existing technologies either only provide assistance to the hip joint without active support for the spine, or achieve spinal assistance by setting up an independent drive unit in the back. However, both suffer from problems such as large structural weight, drive redundancy, and high system complexity.

[0008] To achieve effective reuse of the power from the side-mounted motor for the spinal support structure without increasing the number of additional drive units, resolve motion conflicts of the power source, and realize a time-sharing assistive exoskeleton system, thus achieving "time-sharing intervention" of hip and spinal assistance, this invention designs an underactuated rigid-flexible hybrid assistive exoskeleton based on origami variable stiffness support, solving the aforementioned problems. Summary of the Invention

[0009] To address the shortcomings of existing technologies, the purpose of this invention is to provide an underactuated rigid-flexible hybrid assisted exoskeleton based on origami variable stiffness support.

[0010] According to the present invention, an underactuated rigid-flexible hybrid exoskeleton based on origami variable stiffness support includes: a lumbar support assembly, a lateral drive unit, a thigh linkage assembly, a central spinal support assembly, a coupling transmission mechanism, and a back rigid structure frame. The lumbar support assembly extends horizontally; two sets of the side drive units are symmetrically installed on the left and right sides of the lumbar support assembly; the thigh linkage assembly is connected to the power output shaft of the side drive unit and extends downward; the back rigid structure frame is located above the central spinal support assembly; the central spinal support assembly is flexibly connected between the lumbar support assembly and the back rigid structure frame. The central spinal support assembly includes: an elastic spring, a first-stage origami actuator, and a second-stage origami structure; the top end of the elastic spring is fixed to the rigid back frame, and the bottom end is fixed to the top end of the second-stage origami structure and is vertically connected to the rigid back frame; the bottom end of the first-stage origami actuator is rotatably connected to the lumbar support assembly, and the top end of the first-stage origami actuator is fixed to the bottom end of the second-stage origami structure and is rotatably connected to the rigid back frame; The coupling transmission mechanism includes a flexible traction cable. One end of the flexible traction cable is connected to the side-mounted drive unit, and the other end is connected to its bottom end along the tangent direction of the outer edge of the first-stage origami actuator. The flexible traction cables matched by the two side-mounted drive units are connected to the opposite side of the first-stage origami actuator, and the flexible traction cable has a preset slack margin.

[0011] Preferably, the back rigid structure frame includes a crossbeam and a connecting plate, with the crossbeam positioned above the waist support assembly; the connecting plate is fixed to the center of the crossbeam and extends downward.

[0012] Preferably, the rigid back frame is provided with an upper limb gravity compensation component, which includes a slide and a support arm. The slide is vertically opened on both sides of the crossbeam, and the support arm is inserted into and lifted and connected to the slide. The top of the support arm is bent forward horizontally and extended forward. The front end of the support arm is fixedly connected to a downwardly extending shoulder wear piece, and the bottom end of the shoulder wear piece is provided with a shoulder strap buckle. The slide is vertically spaced with at least two height adjustment holes, and a positioning pin inserted into the height adjustment hole is inserted into the support arm.

[0013] Preferably, the central spinal support assembly further includes: a rotary drive disk, a second-stage rigid-flexible hybrid guide assembly, a cylindrical fixing frame, and a circular bearing; The second-stage rigid-flexible hybrid guide component is a cylindrical structure. The second-stage rigid-flexible hybrid guide component extends vertically and is fixed to the crossbeam. The inner wall of the second-stage rigid-flexible hybrid guide component is provided with a vertically extending slide rail and a slider that slides along the slide rail. The elastic spring and the second-stage origami structure are housed in the second-stage rigid-flexible hybrid guide assembly. The top of the elastic spring is fixed to the top of the second-stage rigid-flexible hybrid guide assembly, and the connection end between the elastic spring and the second-stage origami structure is fixed to the slider. The cylindrical fixing frame is fixed to the connecting plate and connected to the bottom end of the second-stage rigid-flexible hybrid guide assembly; the outer ring of the circular bearing is fixed to the top of the inner wall of the cylindrical fixing frame, and the inner ring of the circular bearing is fixedly connected to the top of the first-stage origami actuator and the bottom end of the second-stage origami structure. The rotary drive disk is fixedly connected to the bottom of the first-stage origami actuator. The rotary drive disk is housed inside a bearing, and a cylindrical frame is fixed to the outside of the bearing. The cylindrical frame is fixed to the waist support assembly.

[0014] Preferably, the first-stage origami actuator and the second-stage origami structure adopt a Kresling configuration.

[0015] Preferably, the first-stage origami actuator and the top and bottom of the second-stage origami structure are provided with discs.

[0016] Preferably, the dual-channel torque distribution structure includes a flat flange structure and a winding reel; the flat flange structure is coaxially fixed to the power output shaft of the side drive unit, and the thigh linkage assembly is radially fixedly connected along the flat flange structure; the winding reel is rotatably connected to the housing of the side drive unit and meshes with the power output shaft of the side drive unit, and a groove is provided in the middle of the side wall of the winding reel, and the winding reel winds and pulls the flexible traction cable.

[0017] Preferably, the flexible traction cable includes a left flexible traction cable and a right flexible traction cable deployed on opposite sides. After being led out from the matching reel, the left and right flexible traction cables are turned by guide pulleys set at the corners on both sides of the waist support assembly, and are connected to the left and right force points of the rotary drive disk in a double-sided cross layout.

[0018] Preferably, an upper power control compartment is provided behind the crossbeam. The upper power control compartment has a backpack-like structure and integrates a battery and a control module.

[0019] Preferably, the upper power control compartment is connected to a data transmission device, which includes an upper data transmission device and a lower data transmission device. The lower data transmission device is made of corrugated metal tubing, with its upper and lower ends movably connected between the crossbeam and the waist support assembly. The data cable is placed inside the hollow part. The upper data transmission device is electrically connected to the data cable of the upper power control compartment and the lower data transmission device.

[0020] Compared with the prior art, the present invention has the following beneficial effects: 1. Time-sharing assistance, in accordance with biomechanical principles: By pre-setting cable slack, a single drive source prioritizes providing assistance to the hip joint in the early stages of the movement, and then drives the spinal support structure to intervene in the middle and later stages of the movement, achieving time-sharing coordinated assistance in accordance with the lumbar spine-pelvis rhythm.

[0021] 2. Dual-stage cushioning and flexible impact resistance: An innovative "second-stage rigid-flexible hybrid guide component" is designed, integrating an elastic spring and a second-stage origami structure in series inside a rigid sleeve. When a speed difference occurs between hip drive and spinal response (such as when the motor retracts the cord too quickly), the impact force is first absorbed by the spring and converted into compression stroke, which then drives the second-stage origami structure to compress. Utilizing the structural damping characteristics of the origami structure under compression, the impact energy is further dissipated, thereby achieving multi-stage flexible cushioning and greatly improving wearing comfort and system durability.

[0022] 3. Stable structure and efficient transmission: A cylindrical fixing frame combined with a circular bearing serves as the connection hub between the first and second stage components, and is fixed to the extension support plate of the rigid back structure. This design ensures that the axial tension of the first-stage origami actuator can be smoothly and with low friction transmitted to the back frame during rotation and retraction, while effectively isolating the rotational torque from interfering with the upper structure.

[0023] 4. Strong back adaptability and balanced force distribution: The rigid back frame adopts an inverted U-shaped frame design and connects to the spinal components through a central extended support plate. This not only ensures the lateral balance of force on the left and right shoulders, but also achieves precise adaptation for users of different heights through the height adjustment mechanism on the vertical support arm.

[0024] 5. High system integration: It realizes the functions of lower limb assistance, spinal support and upper limb gravity compensation within the same structural system. The structure is compact and suitable for long-term wear. Attached Figure Description

[0025] Other features, objects, and advantages of the present invention will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings: Figure 1 This is a rear view schematic diagram of the overall structure of the exoskeleton robot of the present invention.

[0026] Figure 2 This is a schematic diagram of the side-mounted drive unit and the winding mechanism.

[0027] Figure 3 This is a cross-sectional view of the internal structure of the central spine support assembly.

[0028] Figure 4 This is a rearward view of the entire device.

[0029] Figure 5 This is a schematic diagram of the Kresling configuration.

[0030] Figure 6 This is a cross-sectional view of the Kresling configuration.

[0031] The diagram shows: 1. Lumbar support assembly; 2. Side-mounted drive unit; 21. Flat flange structure; 22. Winding reel; 3. Thigh linkage assembly; 4. Central spinal support assembly; 41. First-stage origami actuator; 42. Second-stage rigid-flexible hybrid guide assembly; 43. Cylindrical fixing frame; 411. Rotary drive disk; 421. Elastic spring; 422. Second-stage origami structure; 431. Circular bearing; 5. Flexible traction cable; 51. Left flexible traction cable; 52. Right flexible traction cable; 6. Upper limb gravity compensation assembly; 7. Upper power control compartment; 8. Back rigid structure frame; 9. Data transmission device; 91. Upper data transmission device; 92. Lower data transmission device. Detailed Implementation

[0032] The present invention will now be described in detail with reference to specific embodiments. These embodiments will help those skilled in the art to further understand the present invention, but do not limit the invention in any way. It should be noted that those skilled in the art can make several changes and improvements without departing from the concept of the present invention. These all fall within the protection scope of the present invention.

[0033] like Figures 1-4 As shown, an underactuated rigid-flexible hybrid exoskeleton based on origami variable stiffness support includes: a lumbar support component 1, a lateral drive unit 2, a thigh linkage component 3, a central spinal support component 4, a coupling transmission mechanism, and a back rigid structure frame 8.

[0034] The lumbar support assembly 1 extends horizontally and is worn and fixed to the human waist, providing an installation reference for each functional module. Two sets of side drive units 2 are symmetrically installed on the left and right sides of the lumbar support assembly 1, matching the position of the human hip joint. The thigh linkage assembly 3 is connected to the power output shaft of the side drive unit 2 and extends downward, used to follow or assist the human thigh in completing flexion and extension movements under the drive of the side drive unit 2, thereby providing assistance to the hip joint.

[0035] The rigid back frame 8 is located above the central spinal support component 4, connecting to the upper back of the human body. The central spinal support component 4 is flexibly connected between the lumbar support component 1 and the rigid back frame 8. The rigid back frame 8 is used to evenly transfer the axial tensile force generated by the central spinal support component 4 to the shoulders of the human body, while using the rigid frame structure to ensure the lateral balance of the force on the shoulders.

[0036] The central spinal support assembly 4 includes an elastic spring 421, a first-stage origami actuator 41, and a second-stage origami structure 422. The top end of the elastic spring 421 is fixed to the back rigid structure frame 8, and the bottom end is fixed to the top end of the second-stage origami structure 422, and is vertically connected to the back rigid structure frame 8. The bottom end of the first-stage origami actuator 41 is rotatably connected to the lumbar support assembly 1, and the top end of the first-stage origami actuator 41 is fixed to the bottom end of the second-stage origami structure 422, and is rotatably connected to the back rigid structure frame 8.

[0037] The coupling transmission mechanism includes a flexible traction cable 5. One end of the flexible traction cable 5 is connected to the side-mounted drive unit 2, and the other end is connected to the bottom end of the first-stage origami actuator 41 along the tangent direction of its outer edge. The flexible traction cables 5 matched by the two side-mounted drive units 2 are connected to the opposite side of the first-stage origami actuator 41, and the flexible traction cable 5 is preset with a slack margin.

[0038] The working principle of this application is as follows: the central spinal support component 4 adopts a segmented composite structure. The first-stage origami actuator 41 located at the bottom generates axial contraction force under the rotational drive, providing support force for the rigid back structure frame 8. The second-stage origami structure 422 is used to connect the first-stage origami actuator 41 and the rigid back structure frame 8 to transmit tension and buffer impact. The slack margin preset by the flexible traction cable 5 is used to realize time-sharing assistance for the hip and spine. When the side drive unit 2 rotates, it first drives the thigh linkage assembly 3 to assist hip extension. After the slack margin is eliminated, it is driven by the flexible traction cable 5, which in turn forces the first-stage origami actuator 41 to contract, and applies traction assistance to the human shoulder through the rigid back structure frame 8.

[0039] Specifically, the rigid back structure 8 includes a crossbeam and a connecting plate. The crossbeam is located above the lumbar support component 1. A fabric shoulder strap is installed on the crossbeam and worn on the upper body to provide support. The shoulder strap is installed by using a plastic plate or other fixing components and screws or bolts to attach it to the crossbeam through the shoulder strap part. The connecting plate is fixed to the center of the crossbeam and extends downward to connect to the top of the central spinal support component 4.

[0040] In one embodiment, the rigid back frame 8 is equipped with an upper limb weight compensation component 6. The upper limb weight compensation component 6 includes a slide groove and a support arm. The slide groove is vertically opened on both sides of the crossbeam. The support arm is inserted into and vertically connected to the slide groove. The top of the support arm is bent forward horizontally and extends forward. The front end of the support arm is fixedly connected to a downwardly extending hook for hanging heavy objects. The slide groove is vertically spaced with at least two height adjustment holes. A positioning pin inserted into the height adjustment hole and passing through the support arm is inserted into the height adjustment hole to adjust the vertical height of the support arm, so that the installation height of the shoulder wearable device can be adjusted up and down to accurately fit the torso length of users of different heights. A bent rigid frame and passive suspension structure are used to assist in raising the human upper limb and passively compensate for the weight of the human upper limb.

[0041] Specifically, the lumbar support component 1 extends in an arc shape along the horizontal direction to fit the shape of the human waist. The inner side of the arc is the wearing position, and the outer side of the arc is used to connect to the central spinal support component 4. The central spinal support component 4 is located in the center of the outer side of the arc of the lumbar support component 1 and extends upward along the direction of the human spine.

[0042] The central spinal support assembly 4 also includes: a rotary drive disk 411, a second-stage rigid-flexible hybrid guide assembly 42, a cylindrical fixing frame 43, and a circular bearing 431.

[0043] The second-stage rigid-flexible hybrid guide assembly 42 is a cylindrical structure. It extends vertically and is fixed to the crossbeam. The inner wall of the second-stage rigid-flexible hybrid guide assembly 42 is provided with a vertically extending slide rail and a slider that slides along the slide rail. The slide rail guides and constrains the axial movement of the top end of the second-stage origami structure 422 and stably transmits the axial contraction force generated by the first-stage origami actuator 41 to the human shoulder. An elastic spring 421 and the second-stage origami structure 422 are housed within the second-stage rigid-flexible hybrid guide assembly 42. The top end of the elastic spring 421 is fixed to the top end of the second-stage rigid-flexible hybrid guide assembly 42, and the connection end between the elastic spring 421 and the second-stage origami structure 422 is fixed to the slider. In case of collision, the second-stage origami structure 422 and the elastic spring 421 provide buffering. When the hip drive and the spinal response create a speed conflict, the axial force on the first-stage origami actuator 41 is forced to be converted into a torsional force along the top of the first-stage origami actuator 41. The bottom of the second-stage origami structure 422 is subjected to the torsional force transmitted by the first-stage origami actuator 41. The second-stage origami structure 422 itself can convert the torsional force from the first-stage origami actuator 41 into an axial force and transmit it to the elastic spring 421 to absorb the impact energy through extension and contraction.

[0044] The elastic buffering logic is as follows: When a speed conflict occurs, such as the driving speed of the side-mounted drive unit 2 being faster than the back extension speed, the distance between the rigid back structure frame 8 and the waist is forced to shorten rapidly. At this time, the second-stage rigid-flexible hybrid guide component 42 is subjected to internal force, and the elastic spring 421 is first compressed to absorb the impact energy. The compression of the elastic spring 421 also causes the second-stage origami structure 422 to be compressed. Since the origami structure is directly compressed, which does not conform to the origami force structure, the nonlinear compression damping characteristics of the origami structure are used to further mitigate the impact force and prevent the system from experiencing excessive impact or jamming.

[0045] The cylindrical fixing frame 43 is fixed to the connecting plate and connected to the bottom end of the second-stage rigid-flexible hybrid guide assembly 42. The outer ring of the circular bearing 431 is fixed to the top end of the inner wall of the cylindrical fixing frame 43, and the inner ring of the circular bearing 431 is fixedly connected to the top end of the first-stage origami actuator 41 and the bottom end of the second-stage origami structure 422, realizing the relative rotational coupling and axial force transmission of the two origami structures.

[0046] The rotary drive disk 411 is fixedly connected to the bottom end of the first-stage origami actuator 41. The rotary drive disk 411 is housed inside a bearing. A cylindrical frame is fixed to the outside of the bearing. A cuboid support extends from the side wall of the frame. The support is screwed to the waist support assembly 1. The rotary drive disk 411 is rotatably connected to the waist support assembly 1 through the bearing. The rotary drive disk 411 rotates and drives the first-stage origami actuator 41 to axially retract.

[0047] In one embodiment, the first-stage origami actuator 41 and the second-stage origami structure 422 adopt a Kresling configuration.

[0048] The Kresling configuration of the first-stage origami actuator 41 and the second-stage origami structure 422 adopts a rigid-flexible multi-material composite integrated molding structure. Specifically, the Kresling configuration includes a first triangle and a second triangle, both of which are non-equilateral triangles. The long sides of the first and second triangles are movably connected to each other to form a valley fold line, which is recessed into the cylinder when the structure undergoes axial contraction. Multiple sets of first and second triangles are arranged circumferentially along an axis, with the first triangles movably connected to adjacent sets of second triangles to form a first mountain fold line. Multiple sets of first and second triangles are spliced ​​into a ring structure, with the end faces of the two ends of the ring structure being parallel to each other and movably connected along the axial direction to form a second mountain fold line. The first and second mountain fold lines continuously protrude outwards from the cylinder during deformation under stress.

[0049] The first and second triangular plates use a high-modulus rigid material (polylactic acid PLA) as the core load-bearing area of ​​the triangular panels to ensure sufficient in-plane stiffness under axial and torsional coupled loads, preventing out-of-plane geometric buckling or plastic deformation. At the junctions of adjacent triangular panels (the first mountain fold line, the second mountain fold line, and the valley fold line), a flexible material with high elongation at break (thermoplastic polyurethane elastomer TPU) is composite-filled to construct soft hinges. This spatial rigid-flexible heterogeneous distribution design strictly constrains all spatial folding strains of the structure to the flexible hinge area, thereby eliminating stress concentration and fatigue tearing defects at the multi-faceted intersection vertices of traditional single-material rigid origami, significantly improving the cyclic actuation life, and is applicable to the first-stage origami actuator 41 and the second-stage origami structure 422 in this application.

[0050] The physical mechanism by which this structure generates axial tension does not originate from the material deformation of a single stressed surface, but rather from the inherent "rotation-axial displacement coupling" spatial kinematic characteristics of the Kresling configuration. Since the triangular panels are constrained as rigid, undeformable thin plates, when the side-mounted drive unit 2 drives the rotating drive disk 411 via a flexible traction cable to generate rotational input, relative torsional stress is generated between the bottom end of the structure and the top end, which is constrained by axial guidance. Under this stress field, the externally input lateral rotational displacement is forcibly converted into nonlinear compression of the spatial dihedral angle of the flexible hinge between adjacent rigid triangular panels. As the angle between the first and second mountain fold lines and the valley fold line decreases synchronously, the triangular panel group converges and folds towards the central axis along predetermined folds in three-dimensional space, forcing the cylindrical structure to undergo a rapid axial geometric collapse. Through the aforementioned kinematic constraint mechanism of "zero strain on the panels and large deformation on the hinges," the input lateral torque is efficiently converted into axial contraction motion along the central axis, thereby outputting axial tension on the spinal support component.

[0051] The natural spatial folding of the Kresling configuration must be accompanied by circumferential rotation to achieve the buffering function of the second-level origami structure 422. When its rotational degrees of freedom are forcibly locked by the guide components and it is subjected to only pure axial compression, severe kinematic interference occurs within the structure. In this state, the impact kinetic energy cannot be released through the conventional smooth folding path, but is forced to be converted into two parts of resistance: one is the physical compression interference generated by the rigid triangular panel (PLA) in the thickness direction; the other is the extremely high tensile strain energy generated by the flexible hinge (TPU) under forced deformation. This special compression mode under constrained conditions endows the second-level origami structure with extremely high nonlinear stiffness increment and material damping dissipation characteristics, enabling it to effectively absorb and mitigate instantaneous impact forces and assume the passive buffering function of the system.

[0052] In one embodiment, the first-stage origami actuator 41 and the second-stage origami structure 422 are provided with disks at their top and bottom ends.

[0053] In one embodiment, the Kresling configuration has a first or second triangular plate at both circumferential ends fixed with a lifting lug, which is fixedly connected to the disk.

[0054] The side-mounted drive unit 2 is equipped with a dual-channel torque distribution structure, which includes a flat flange structure 21 and a winding reel 22. The flat flange structure 21 is coaxially fixed to the power output shaft of the side-mounted drive unit 2, serving as the first power channel, and the thigh linkage assembly 3 is radially fixedly connected along the flat flange structure 21. The winding reel 22 is rotatably connected to the housing of the side-mounted drive unit 2 and meshes with the power output shaft of the side-mounted drive unit 2, serving as the second power channel. A groove is provided in the middle of the side wall of the winding reel 22 for winding and pulling the flexible traction cable 5.

[0055] The coupling transmission mechanism is equipped with time-sharing intervention logic: when the human body is bent over, the flexible traction cable 5 has a slack length reserved in the initial installation state or the initial winding section of the winding wheel 22 to match a specific angle range of the hip joint (such as 0°-30°); in the initial stage of the movement, the winding wheel 22 prioritizes to retract the slack, and the central spinal support component 4 does not intervene; when the angle exceeds the set range, the flexible traction cable 5 straightens and drives the rotating drive disc 411 to start driving the spine.

[0056] In one embodiment, the flexible traction cable 5 includes a left flexible traction cable 51 and a right flexible traction cable 52 deployed on opposite sides. After being led out from the matching winding reel 22, the left flexible traction cable 51 and the right flexible traction cable 52 are turned by guide pulleys set at the corners on both sides of the waist support assembly 1. They are connected to the left and right force points of the rotary drive disk 411 in a double-sided cross layout to form a resultant torque dominated by torsion. That is, the left flexible traction cable 51 output by the left side drive unit 2 is connected to the right force point of the rotary drive disk 411, and the right flexible traction cable 52 output by the right side drive unit 2 is connected to the left force point of the rotary drive disk 411 to form a resultant torque dominated by torsion on the rotary drive disk 411, which cancels the radial component force and ensures the stability of the rotation input of the first-stage origami actuator 41.

[0057] When the side drive unit 2 rotates to assist the human body in standing up, the side drive unit 2 synchronously drives the external winding wheel 22 to tighten the flexible traction cable 5, and drives the rotating drive disk 411 to rotate through the double-sided cross traction method; utilizing the inherent axial-torsional coupling characteristics of the origami configuration, the rotational motion of the rotating drive disk 411 forces the first-stage origami actuator 41 to axially contract; since the upper end of the first-stage origami actuator 41 is connected to the second-stage rigid-flexible hybrid guide component 42 through the circular bearing 431 in the cylindrical fixing frame 43 and then to the back rigid structure frame 8, and the back rigid structure frame 8 is connected to the upper limb gravity compensation component 6 and the shoulder straps worn on the body, the axial contraction of the first-stage origami actuator 41 will apply a traction component along the spinal direction to the human body's shoulders and back through the back rigid structure frame 8, thereby forming a torque in the human body's lumbosacral region that is conducive to trunk extension, assisting the human body in completing the action of standing up from a bent-over posture to an upright posture.

[0058] Behind the crossbeam is an upper power control compartment 7, which has a backpack-like structure and integrates a battery and control module.

[0059] In one embodiment, the upper power control compartment 7 is connected to a data transmission device 9. The data transmission device 9 is used for data connection and control between the upper power control compartment 7 and the side-mounted drive unit 2. The data transmission device 9 includes an upper data transmission device 91 and a lower data transmission device 92. The lower data transmission device 92 is made of corrugated metal tubing, with its upper and lower ends movably connected between the crossbeam and the waist support assembly 1. It has a hollow interior for housing data cables, possessing a certain degree of plasticity and the ability to bend and deform, without hindering bending movements or the movement of the upper and lower parts of the exoskeleton. The upper data transmission device 91 electrically connects the data cables of the upper power control compartment 7 and the lower data transmission device 92.

[0060] This invention simultaneously drives the hip assistance and spinal traction components via a side-mounted drive unit 2. Utilizing the preset relaxation amount of the flexible traction cable 5, it prioritizes hip joint extension during the initial stage of standing up, only engaging the spinal support structure after the relaxation phase is complete, achieving coordinated assistance of "hip extension first, then spine extension." The spinal support employs an origami structure, whose rotational drive enables active axial contraction. When the hip and spine movement speeds conflict, the built-in elastic spring 421 and the second-stage origami structure 422 can absorb the impact in stages, ensuring smooth and safe wear. The entire system achieves time-sharing assistance for the hip and spine and upper limb gravity compensation under a single power source.

[0061] This application has the following technical points: First, without setting up an independent drive source for the back, it achieves effective reuse of the power of the hip side drive unit 2, so that the exoskeleton can provide active assistance to the human hip joint and spine while maintaining the lightweight and simplified system structure.

[0062] Second, the exoskeleton provides varying levels of support to the spine during different phases of movement, such as bending over and standing up. This avoids unnecessary constraints on the spine during bending over and provides the necessary effective support during standing up.

[0063] Third, under the condition of a single driving source, the time-sharing intervention of hip assistance and spinal assistance is realized, avoiding speed conflict, stroke interference and wearing discomfort caused by the asynchronous movement of hip joint extension and spinal extension, so that the assistance process of the exoskeleton is more in line with the human lumbar spine-pelvis rhythm.

[0064] This application achieves time-sharing coordinated hip-spine assistance that conforms to human biomechanical characteristics by using underactuated coupling and flexible force transmission mechanism at the structural level without adding an independent drive unit for the back.

[0065] In the description of this application, it should be understood that the terms "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application 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 this application.

[0066] Specific embodiments of the present invention have been described above. It should be understood that the present invention is not limited to the specific embodiments described above, and those skilled in the art can make various changes or modifications within the scope of the claims, which do not affect the essence of the present invention. Unless otherwise specified, the embodiments and features described in this application can be arbitrarily combined with each other.

Claims

1. An underactuated rigid-flexible hybrid powered exoskeleton based on origami variable stiffness support, characterized in that, include: Lumbar support assembly (1), lateral drive unit (2), thigh linkage assembly (3), central spinal support assembly (4), coupling transmission mechanism and back rigid structure frame (8). The lumbar support assembly (1) extends horizontally; two sets of side drive units (2) are symmetrically installed on the left and right sides of the lumbar support assembly (1); the thigh linkage assembly (3) is connected to the power output shaft of the side drive unit (2) and extends downward; the back rigid structure frame (8) is located above the central spine support assembly (4); the central spine support assembly (4) is flexibly connected between the lumbar support assembly (1) and the back rigid structure frame (8); The central spinal support assembly (4) includes: an elastic spring (421), a first-stage origami actuator (41), and a second-stage origami structure (422); the top end of the elastic spring (421) is fixed to the back rigid structure frame (8), and the bottom end is fixed to the top end of the second-stage origami structure (422) and is vertically connected to the back rigid structure frame (8); the bottom end of the first-stage origami actuator (41) is rotatably connected to the waist support assembly (1), and the top end of the first-stage origami actuator (41) is fixed to the bottom end of the second-stage origami structure (422) and is rotatably connected to the back rigid structure frame (8); The coupling transmission mechanism includes a flexible traction cable (5), one end of which is connected to the side-mounted drive unit (2), and the other end is connected to the bottom end of the first-stage origami actuator (41) along the tangent direction of its outer edge. The flexible traction cables (5) matched by the two side-mounted drive units (2) are connected to the opposite side of the first-stage origami actuator (41), and the flexible traction cable (5) has a preset slack margin.

2. The underactuated rigid-flexible hybrid powered exoskeleton based on origami variable stiffness support according to claim 1, characterized in that, The rigid back structure frame (8) includes a crossbeam and a connecting plate. The crossbeam is positioned above the waist support assembly (1). The connecting plate is fixed to the center of the crossbeam and extends downward.

3. The underactuated rigid-flexible hybrid assisted exoskeleton based on origami variable stiffness support according to claim 2, characterized in that, The rigid back frame (8) is provided with an upper limb gravity compensation component (6). The upper limb gravity compensation component (6) includes a slide and a support arm. The slide is vertically opened on both sides of the crossbeam. The support arm is inserted into and lifted and connected to the slide. The top of the support arm is bent forward horizontally and extended. The front end of the support arm is fixedly connected to a downwardly extending shoulder wear piece. The bottom end of the shoulder wear piece is provided with a shoulder strap buckle. The slide is vertically spaced with at least two height adjustment holes. A positioning pin inserted into the height adjustment hole is inserted through the support arm.

4. The underactuated rigid-flexible hybrid exoskeleton based on origami variable stiffness support according to claim 3, characterized in that, The central spinal support assembly (4) also includes: a rotary drive disk (411), a second-stage rigid-flexible hybrid guide assembly (42), a cylindrical fixing frame (43), and a circular bearing (431). The second-stage rigid-flexible hybrid guide component (42) is a cylindrical structure. The second-stage rigid-flexible hybrid guide component (42) extends vertically and is fixed to the crossbeam. The inner wall of the second-stage rigid-flexible hybrid guide component (42) is provided with a vertically extending slide rail and a slider that slides along the slide rail. The elastic spring (421) and the second-level origami structure (422) are housed in the second-level rigid-flexible hybrid guide assembly (42). The top end of the elastic spring (421) is fixed to the top end of the second-level rigid-flexible hybrid guide assembly (42), and the connecting end of the elastic spring (421) and the second-level origami structure (422) is fixed to the slider. The cylindrical fixing frame (43) is fixed to the connecting plate and connected to the bottom end of the second-stage rigid-flexible hybrid guide assembly (42); the outer ring of the circular bearing (431) is fixed to the top end of the inner wall of the cylindrical fixing frame (43), and the inner ring of the circular bearing (431) is fixedly connected to the top end of the first-stage origami actuator (41) and the bottom end of the second-stage origami structure (422); The rotary drive disk (411) is fixedly connected to the bottom end of the first-stage origami actuator (41). The rotary drive disk (411) is housed inside a bearing. A cylindrical frame is fixed to the outside of the bearing. The cylindrical frame is fixed to the waist support assembly (1).

5. The underactuated rigid-flexible hybrid assisted exoskeleton based on origami variable stiffness support according to claim 4, characterized in that, The first-stage origami actuator (41) and the second-stage origami structure (422) adopt the Kresling configuration.

6. The underactuated rigid-flexible hybrid assisted exoskeleton based on origami variable stiffness support according to claim 5, characterized in that, The first-stage origami actuator (41) and the second-stage origami structure (422) are provided with discs at their top and bottom ends.

7. The underactuated rigid-flexible hybrid assisted exoskeleton based on origami variable stiffness support according to claim 6, characterized in that, The side-mounted drive unit (2) is provided with a dual-channel torque distribution structure, which includes a flat flange structure (21) and a winding wheel (22). The flat flange structure (21) is coaxially fixed to the power output shaft of the side-mounted drive unit (2), and the thigh linkage assembly (3) is radially fixedly connected along the flat flange structure (21). The winding wheel (22) is rotatably connected to the housing of the side-mounted drive unit (2) and meshes with the power output shaft of the side-mounted drive unit (2). A groove is provided in the middle of the side wall of the winding wheel (22), and the winding wheel (22) winds and pulls the flexible traction cable (5).

8. The underactuated rigid-flexible hybrid assisted exoskeleton based on origami variable stiffness support according to claim 7, characterized in that, The flexible traction cable (5) includes a left flexible traction cable (51) and a right flexible traction cable (52) deployed on opposite sides. After the left flexible traction cable (51) and the right flexible traction cable (52) are led out from the matching reel (22), they are turned by the guide pulleys set at the corners on both sides of the waist support assembly (1), and are connected to the left and right force points of the rotating drive disk (411) in a double-sided cross layout.

9. The underactuated rigid-flexible hybrid assisted exoskeleton based on origami variable stiffness support according to claim 2, characterized in that, The upper power control compartment (7) is located behind the crossbeam. The upper power control compartment (7) has a backpack-like structure and integrates a battery and control module.

10. The underactuated rigid-flexible hybrid assisted exoskeleton based on origami variable stiffness support according to claim 9, characterized in that, The upper power control compartment (7) is connected to a data transmission device (9), which includes an upper data transmission device (91) and a lower data transmission device (92). The lower data transmission device (92) is made of metal corrugated pipe, and its upper and lower ends are movably connected between the crossbeam and the waist support component (1). The data line is placed inside the hollow part. The upper data transmission device (91) is electrically connected to the data line between the upper power control compartment (7) and the lower data transmission device (92).

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