Rope-driven hip joint exoskeleton facilitating force transmission

Abstract

The invention relates to the technical field of robots, in particular to a rope-driven hip joint exoskeleton convenient for force transmission, which comprises a back frame, a waist frame, a shaft connecting frame, a leg frame and Bowden ropes, and is characterized in that the waist frame comprises a waist frame double-layer carbon plate, a tension sensor, a Bowden tube seat, a Bowden tube seat pulley and an adapter pulley; the shaft connecting frame comprises shaft connecting pieces, a carbon fiber cantilever beam and a carbon fiber cantilever beam pulley, the shaft connecting pieces comprise an upper side shaft connecting piece, a middle shaft connecting piece and a lower side shaft connecting piece, and the carbon fiber cantilever beam pulley is installed at the free end of the carbon fiber cantilever beam; and the Bowden rope sequentially bypasses the Bowden tube seat pulley, the carbon fiber cantilever beam pulley and the switching pulley and then is connected with the tension sensor. The exoskeleton provided by the invention is light in weight, convenient to assemble and high in interaction flexibility, and the applied force can be doubled.

Description

Technical Field

[0001] This invention relates to the field of robotics, and more particularly to a cable-driven hip exoskeleton that facilitates force transmission. Background Technology

[0002] Hip exoskeletons, as assistive devices that enhance human mobility, hold great potential in both clinical rehabilitation and industrial applications. These systems can reduce metabolic energy consumption during walking, improve musculoskeletal function in the elderly or those with disabilities, and play an important role in improving physical performance and conducting therapeutic interventions.

[0003] However, existing hip exoskeletons generally have some problems. First, the connection between the exoskeleton actuator and the human body is generally rigid, lacking elastic elements for cushioning, which can easily cause control oscillations and damage to the human joint. Second, rope-driven exoskeletons generally place the pulley end at the joint, which functions similarly to placing a motor at the joint, and has not yet completely broken away from the mechanical structure of exoskeletons in the form of joint motors.

[0004] Third, existing exoskeletons cannot simultaneously meet the requirements of lightweight design and high torque output performance. Existing cable-driven hip exoskeletons generally weigh over 4 kg, and if a greater torque output is required, the weight of the exoskeleton must be increased accordingly.

[0005] How to provide a flexible force transmission path through ropes, effectively decouple actuators from joints, enhance human comfort, and improve system compliance remains a challenge that needs to be overcome. Summary of the Invention

[0006] The technical problem to be solved by the present invention is to provide a rope-driven hip exoskeleton that facilitates force transmission, is lightweight, easy to assemble, can double the applied force, reduces the overall lateral dimension of the exoskeleton, and increases the flexibility, reliability and comfort of human interaction with the exoskeleton.

[0007] A rope-driven hip exoskeleton for easy force transmission includes a back frame, a lumbar frame, a shaft connection frame, a leg frame, and Bowden ropes. The lumbar frame is fixedly connected to both ends of the back frame via a lumbar-back connector. The lumbar frame includes a double-layer carbon fiber plate, a tension sensor, a Bowden tube seat, a Bowden tube seat pulley, and a transition pulley. The tension sensor and the Bowden tube seat are both fixedly installed between the double-layer carbon fiber plates of the lumbar frame, with the tension sensor and the Bowden tube seat facing each other. The Bowden tube seat pulley and the transition pulley are both mounted on the Bowden tube seat. The shaft connection frame includes a shaft connector, a carbon fiber cantilever beam, and a carbon fiber suspension... The arm beam pulley includes an upper shaft connector, a middle shaft connector, and a lower shaft connector. The upper shaft connector and the middle shaft connector are rotatably connected, and the lower shaft connector and the middle shaft connector are connected. The upper shaft connector is fixedly connected to the double-layer carbon fiber plate of the waist frame, and the lower shaft connector is fixedly connected to the leg frame. One end of the carbon fiber cantilever beam is fixedly connected to the middle shaft connector. The carbon fiber cantilever beam pulley is installed at the free end of the carbon fiber cantilever beam. The Bowden rope passes sequentially around the Bowden tube seat pulley, the carbon fiber cantilever beam pulley, and the adapter pulley before connecting to the tension sensor.

[0008] In the optimized configuration, the adapter pulley is located to the side and below the Bowden tube seat pulley, the carbon fiber cantilever beam pulley is located directly below the Bowden tube seat pulley, and the tension sensor is horizontally opposite to the adapter pulley.

[0009] Furthermore, the double-layer carbon plate of the waist frame has a C-shaped structure, and the end of the double-layer carbon plate of the waist frame connected to the shaft connector is lower than the end opposite to the pulley of the carbon fiber cantilever beam. The upper shaft connector includes a waist connecting part, an intermediate shaft connector connecting part, and a limiting plate fixed between the waist connecting part and the intermediate shaft connector connecting part. The upper shaft connector is fixedly connected to the double-layer carbon plate of the waist frame at the waist connecting part by bolts. The intermediate shaft connector and the upper shaft connector are connected at the intermediate shaft connector connecting part by ball bearings and a D-shaped shaft.

[0010] Furthermore, the lower part of the intermediate shaft connector has an opening, and the lower shaft connector and the intermediate shaft connector are connected at the opening by locking screws.

[0011] Furthermore, a magnetic encoder is installed on the shaft connector. The magnetic encoder includes a magnetic encoder base, a magnetic encoder body, a magnet, and a magnetic encoder cover. The magnetic encoder base is fixedly installed on the upper shaft connector. The magnetic encoder body is installed on the magnetic encoder base. The magnet is fixedly installed on the D-shaped shaft and faces the magnetic encoder body. The magnetic encoder cover is fastened to the magnetic encoder base.

[0012] The optimized back frame includes a carbon fiber plate and a back brace. The carbon fiber plate and the back brace are fixedly connected, and the back brace is located inside the carbon fiber plate. The carbon fiber plate and the back brace are provided with two corresponding sets of back frame strap slots.

[0013] Furthermore, the back carbon plate and the waist-back connector both have multiple rows of threaded holes, and the back carbon plate and the waist-back connector are fixedly connected by bolts at the multiple rows of threaded holes.

[0014] The optimized lumbar frame also includes a lumbar support, which is fixedly installed on the inner side of the double-layer carbon plate of the lumbar frame, and the lumbar support is provided with a lumbar frame strap through a groove.

[0015] The optimized leg frame includes a double-layer carbon fiber plate and a leg guard. The upper end of the double-layer carbon fiber plate is fixedly connected to the lower side shaft connector, and the leg guard is fixedly installed on the lower inner side of the double-layer carbon fiber plate.

[0016] Furthermore, an upper fixing component and a lower fixing component are fixedly installed between the two layers of carbon plates on the legs.

[0017] Beneficial effects of the invention: The present invention provides a rope-driven hip exoskeleton that facilitates force transmission, which has the following advantages: 1. A hybrid transmission system using Bowden ropes and pulleys was employed, which reduced the lateral structural dimensions, ensuring the exoskeleton's compactness while increasing its torque output.

[0018] 2. The design of the shaft connectors and cantilever beams provides the exoskeleton with series elasticity, increases the flexibility of human-exoskeleton interaction, and ensures the comfort of human-computer interaction.

[0019] 3. By designing a pulley system, the tension sensor is placed at the waist, which not only reduces the movement of the tension sensor but also lowers the noise of the tension sensor measurement.

[0020] 4. The double-layer carbon plate structure of the waist frame ensures structural strength, while allowing for the placement of tension sensors, the routing of Bowden ropes, and the transmission of force. Furthermore, the design of the double-layer carbon plate structure of the waist frame and the shaft connection frame achieves reliable limiting, ensuring that the range of motion of the exoskeleton is reliably limited to the normal range of human activity, preventing damage to human bones or joints.

[0021] 5. Through the structural design of the shaft connector, the leg has a passive lateral degree of freedom, which can realize the abduction and adduction of the leg, making it more suitable for the characteristics of human kinematics.

[0022] 6. The system is made of lightweight and high-strength materials, resulting in a lower overall system weight and easier manufacturing. Attached Figure Description

[0023] Figure 1 This is a three-dimensional structural schematic diagram of the present invention.

[0024] Figure 2 This is a schematic diagram of the main structure of the present invention.

[0025] Figure 3 This is a top view of the structure of the present invention.

[0026] Figure 4 This is a side view of the structure of the present invention.

[0027] Figure 5 This is a schematic diagram of the Bowden rope connection of the present invention.

[0028] Figure 6 This is an exploded schematic diagram of the waist frame of the present invention.

[0029] Figure 7 This is an exploded view of the shaft connection frame of the present invention.

[0030] In the diagram: 1. Back frame; 1-1. Back carbon plate; 1-2. Back brace; 1-3. Back frame strap slot; 2. Waist frame; 2-1. Inner waist carbon plate; 2-2. Outer waist carbon plate; 2-3. Tension sensor body; 2-4. Tension sensor base; 2-5. Tension sensor top cover; 2-6. Bowden tube seat; 2-7. Bowden tube seat pulley; 2-8. Adapter pulley; 2-9. Waist brace; 2-10. Waist frame strap slot; 3. Shaft connection frame; 3-1. Upper shaft connector; 3-1-1. Waist connection part; 3-1-2. Intermediate shaft connector. 3-1-3 Connecting part; Limiting plate; 3-2 Intermediate shaft connector; 3-3 Lower side shaft connector; 3-4 Carbon fiber cantilever beam; 3-5 Cantilever beam connector; 3-6 Carbon fiber cantilever beam pulley; 3-7 Ball bearing; 3-8 D-shaped shaft; 4 Leg frame; 4-1 Inner waist carbon plate; 4-2 Outer waist carbon plate; 4-3 Upper fixing part; 4-4 Lower fixing part; 4-5 Leg guard; 5 Waist and back connector; 6 Magnetic encoder; 6-1 Magnetic encoder base; 6-2 Magnetic encoder body; 6-3 Magnet; 6-4 Magnetic encoder top cover. Detailed Implementation

[0031] A rope-driven hip exoskeleton for easy force transmission, structural diagram shown below. Figures 1 to 4As shown, the structure includes a back frame 1, a waist frame 2, a shaft connecting frame 3, a leg frame 4, and Bowden ropes (not shown). The waist frame is fixedly connected to both ends of the back frame via a waist-back connector 5. The three components can be connected by bolts. The waist-back connector can be made of aluminum alloy using CNC machining. The design of the waist-back connector provides a connection between the back frame and the waist frame, forming a closed load-bearing structure.

[0032] The waist frame includes a double-layer carbon plate, a tension sensor, a Bowden tube seat 2-6, a Bowden tube seat pulley 2-7, and a transfer pulley 2-8. The double-layer carbon plate includes an inner carbon plate 2-1 and an outer carbon plate 2-2. The inner carbon plate and the outer carbon plate can be fixedly connected by bolts.

[0033] The tension sensor and Bowden tube base are both fixedly installed between the double-layer carbon plates of the lumbar frame, with the tension sensor and Bowden tube base positioned opposite each other. The Bowden tube base pulley and adapter pulley are both mounted on the Bowden tube base. Specifically, the tension sensor includes a tension sensor base 2-4, a tension sensor body 2-3, and a tension sensor cover 2-5. The tension sensor base is fixedly installed between the double-layer carbon plates of the lumbar frame. One end of the tension sensor body is connected to the tension sensor base, and the other end is connected to the tension sensor cover. The tension sensor is used to measure the interaction force between the human body and the exoskeleton. Fixing both the tension sensor and Bowden tube base between the double-layer carbon plates of the lumbar frame minimizes collisions between the human arm and the Bowden rope and tension sensor, while ensuring that force transmission occurs in the sagittal plane without generating additional torsion.

[0034] The shaft connection frame includes a shaft connector, a carbon fiber cantilever beam 3-4, and a carbon fiber cantilever beam pulley 3-6. The shaft connector includes an upper shaft connector 3-1, a middle shaft connector 3-2, and a lower shaft connector 3-3. The upper shaft connector and the middle shaft connector are rotatably connected, and the lower shaft connector and the middle shaft connector are connected. The upper shaft connector is fixedly connected to the double-layer carbon fiber plate of the waist frame, and the lower shaft connector is fixedly connected to the leg frame. One end of the carbon fiber cantilever beam is fixedly connected to the middle shaft connector. A carbon fiber cantilever beam pulley is installed on the free end of the carbon fiber cantilever beam via the cantilever beam connector 3-5. The Bowden rope passes sequentially around the Bowden tube seat pulley, the carbon fiber cantilever beam pulley, and the adapter pulley before connecting to the tension sensor. A detailed diagram of the Bowden rope connection is shown below. Figure 5 As shown.

[0035] This invention provides a rope-driven hip exoskeleton that facilitates force transmission. Through the design of the waist frame and the shaft connection frame, the pulley system effectively changes the force transmission direction of the Bowden rope. Within an effective distance (lever arm), the applied force can be doubled through a mechanism similar to a movable pulley, reducing the overall lateral dimension of the exoskeleton. At the same time, placing the tension sensor in the waist area where the movement is relatively gentle not only reduces the movement of the tension sensor but also effectively reduces the noise when the tension sensor reads.

[0036] The design of the carbon fiber cantilever beam, although the tensile strength of the plane parallel to the carbon fiber layer is relatively low, can provide a large amount of elastic deformation. It provides controlled series elasticity in the process of force transmission, increases the compliance of the overall force transmission, which is beneficial to the stability of the exoskeleton control and the human joints. It improves the compliance of the human body when interacting with the exoskeleton and ensures the comfort of human-machine interaction.

[0037] Since the main components of this invention can all be made of carbon fiber plates or 3D printed, they are easy to process, have low cost, are lightweight, and are easy to assemble. The components can be connected with screws, nuts, etc.

[0038] The power element that drives the Bowden rope movement in this invention can be fixedly installed on the exoskeleton or placed separately, which makes it convenient for users to reduce weight during rehabilitation.

[0039] Specifically, the adapter pulley can be positioned to the side and below the Bowden tube seat pulley, and the carbon fiber cantilever beam pulley can be positioned directly below the Bowden tube seat pulley. The force sensor is horizontally opposite to the adapter pulley. This design ensures that the Bowden ropes on both sides passing around the carbon fiber cantilever beam pulley are basically parallel, thus ensuring a balanced force distribution and achieving both labor-saving and stability.

[0040] Furthermore, the double-layer carbon steel plate of the waist frame has a C-shaped structure, and the end of the double-layer carbon steel plate of the waist frame connected to the shaft connector is lower than the end opposite to the pulley of the carbon fiber cantilever beam. The upper shaft connector includes a waist connecting part 3-1-1, an intermediate shaft connector connecting part 3-1-2, and a limiting plate 3-1-3 fixed between the waist connecting part and the intermediate shaft connector connecting part. The upper shaft connector is fixedly connected to the double-layer carbon steel plate of the waist frame at the waist connecting part by bolts. The intermediate shaft connector and the upper shaft connector are connected at the intermediate shaft connector connecting part by ball bearing 3-7 and D-shaped shaft 3-8. Specifically, the exploded schematic diagram of the waist frame is shown below. Figure 6 As shown in the exploded view of the shaft connection frame, Figure 7 As shown.

[0041] This structure is designed so that when the Bowden rope drives the carbon fiber cantilever beam to rotate clockwise (i.e., when the legs move backward), the cantilever beam pulleys contact the corresponding double-layer carbon plates of the waist frame, preventing further movement and thus creating a reliable limit, preventing over-movement. When the legs move forward, the carbon fiber cantilever beam rotates counterclockwise. At a certain position, the intermediate shaft connector contacts the limiting plate of the upper shaft connector, preventing further movement and creating a reliable limit. This limiting structure reliably restricts the exoskeleton's extension to approximately 40° and flexion to approximately 90°, conforming to the normal range of human movement.

[0042] Furthermore, the lower part of the intermediate shaft connector has an opening, and the lower shaft connector and the intermediate shaft connector are connected at the opening by locking screws. This design gives the lower shaft connector a passive degree of freedom relative to the intermediate shaft connector, enabling leg abduction and adduction, which is more adaptable to human movement characteristics.

[0043] Furthermore, a magnetic encoder 6 is installed on the shaft connector. The magnetic encoder includes a magnetic encoder base 6-1, a magnetic encoder body 6-2, a magnet 6-3, and a magnetic encoder cover 6-4. The magnetic encoder base is fixedly installed on the upper shaft connector, the magnetic encoder body is installed on the magnetic encoder base, the magnet is fixedly installed on the D-shaped shaft and faces the magnetic encoder body, and the magnetic encoder cover is fastened to the magnetic encoder base. The magnetic encoder can be used to measure the joint angle of the hip exoskeleton.

[0044] The optimized back frame includes a carbon fiber back plate 1-1 and a back brace 1-2. The carbon fiber back plate and the back brace are fixedly connected, with the back brace located inside the carbon fiber back plate. The carbon fiber back plate and the back brace have two corresponding sets of back frame strap slots 1-3. The back brace can be 3D printed to mimic the curvature of the human back, maximizing the contact area with the skin and optimizing pressure distribution.

[0045] Furthermore, the back carbon plate and the waist-back connector both have multiple rows of threaded holes. The back carbon plate and the waist-back connector are fixedly connected by bolts at the multiple rows of threaded holes. This design allows the installation position to be adjusted according to individual user differences.

[0046] The optimized lumbar frame also includes a lumbar support 2-9, which is fixedly installed on the inner side of the double-layer carbon plate of the lumbar frame, and the lumbar support is provided with a lumbar frame strap through groove 2-10.

[0047] The lumbar support can be 3D printed and designed to mimic the curve of the human waist.

[0048] Overall, the connection with the human body allows the straps to pass sequentially through the waist frame strap slots on one side, a set of back frame strap slots, and then in reverse through another set of back frame strap slots and the waist frame strap slots on the other side, forming a strong connection with the human body. This provides stability while achieving a personalized fit and promoting the even distribution of load.

[0049] The optimized leg frame includes a double-layer carbon fiber plate and leg guards 4-5. The upper end of the double-layer carbon fiber plate is fixedly connected to the lower side shaft connector, and the leg guards are fixedly installed on the lower inner side of the double-layer carbon fiber plate.

[0050] The double-layer carbon fiber plate for the legs includes an inner carbon fiber plate 4-1 and an outer carbon fiber plate 4-2. It can reduce weight and increase torsional resistance during force transmission. The upper part of the double-layer carbon fiber plate for the legs can be fixedly connected to the lower side shaft connector by bolts. The leg protector imitates the curvature of the human thigh and can be made by 3D printing to increase the contact area with the human body and make the wearing experience more comfortable. The leg protector can also be tied to the human leg with straps.

[0051] Furthermore, an upper fixing component 4-3 and a lower fixing component 4-4 are fixedly installed between the double carbon plates of the legs. The upper fixing component, the lower fixing component and the double carbon plates of the legs can be fixedly connected to each other by locking screws, thereby fixing the double carbon plates of the legs.

[0052] In summary, the present invention provides a rope-driven hip exoskeleton that facilitates force transmission, is lightweight, easy to assemble, can double the applied force, reduces the overall lateral dimension of the exoskeleton, and increases the flexibility, reliability, and comfort of human-exoskeleton interaction.

[0053] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A rope-driven hip exoskeleton for easy force transmission, characterized in that: The system includes a back frame, a waist frame, a shaft connection frame, a leg frame, and Bowden ropes. The waist frame is fixedly connected to both ends of the back frame via a waist-back connector. The waist frame includes a double-layer carbon fiber plate, a tension sensor, a Bowden tube seat, a Bowden tube seat pulley, and a transition pulley. The tension sensor and the Bowden tube seat are both fixedly installed between the double-layer carbon fiber plates of the waist frame, with the tension sensor and the Bowden tube seat facing each other. The Bowden tube seat pulley and the transition pulley are both installed on the Bowden tube seat. The shaft connection frame includes a shaft connector, a carbon fiber cantilever beam, and a carbon fiber cantilever beam pulley. The connecting components include an upper side shaft connector, an intermediate shaft connector, and a lower side shaft connector. The upper side shaft connector and the intermediate shaft connector are rotatably connected, and the lower side shaft connector and the intermediate shaft connector are connected. The upper side shaft connector is fixedly connected to the double-layer carbon plate of the waist frame, and the lower side shaft connector is fixedly connected to the leg frame. One end of the carbon fiber cantilever beam is fixedly connected to the intermediate shaft connector. The carbon fiber cantilever beam pulley is installed at the free end of the carbon fiber cantilever beam. The Bowden rope passes sequentially around the Bowden tube seat pulley, the carbon fiber cantilever beam pulley, and the adapter pulley before connecting to the tension sensor.

2. The rope-driven hip exoskeleton for facilitating force transmission according to claim 1, characterized in that: The adapter pulley is located to the side and below the Bowden tube seat pulley, the carbon fiber cantilever beam pulley is located directly below the Bowden tube seat pulley, and the tension sensor is horizontally opposite to the adapter pulley.

3. The rope-driven hip exoskeleton for easy force transmission according to claim 2, characterized in that: The double-layer carbon plate of the waist frame has a C-shaped structure, and the end of the double-layer carbon plate of the waist frame connected to the shaft connector is lower than the end opposite to the pulley of the carbon fiber cantilever beam. The upper shaft connector includes a waist connecting part, an intermediate shaft connector connecting part, and a limiting plate fixed between the waist connecting part and the intermediate shaft connector connecting part. The upper shaft connector is fixedly connected to the double-layer carbon plate of the waist frame at the waist connecting part by bolts. The intermediate shaft connector and the upper shaft connector are connected at the intermediate shaft connector connecting part by ball bearings and a D-shaped shaft.

4. The rope-driven hip exoskeleton for easy force transmission according to claim 1, characterized in that: The lower part of the intermediate shaft connector has an opening, and the lower shaft connector and the intermediate shaft connector are connected at the opening by locking screws.

5. A rope-driven hip exoskeleton for facilitating force transmission according to claim 3, characterized in that: A magnetic encoder is installed on the shaft connector. The magnetic encoder includes a magnetic encoder base, a magnetic encoder body, a magnet, and a magnetic encoder cover. The magnetic encoder base is fixedly installed on the upper shaft connector. The magnetic encoder body is installed on the magnetic encoder base. The magnet is fixedly installed on the D-shaped shaft and faces the magnetic encoder body. The magnetic encoder cover is fastened to the magnetic encoder base.

6. A rope-driven hip exoskeleton for facilitating force transmission according to claim 1, characterized in that: The back frame includes a carbon fiber plate and a back brace. The carbon fiber plate and the back brace are fixedly connected, and the back brace is located inside the carbon fiber plate. The carbon fiber plate and the back brace are provided with two corresponding sets of back frame strap slots.

7. A rope-driven hip exoskeleton for facilitating force transmission according to claim 6, characterized in that: Both the back carbon plate and the waist-back connector have multiple rows of threaded holes, and the back carbon plate and the waist-back connector are fixedly connected by bolts at the multiple rows of threaded holes.

8. A rope-driven hip exoskeleton for facilitating force transmission according to claim 6, characterized in that: The lumbar frame also includes a lumbar support, which is fixedly installed on the inner side of the double-layer carbon plate of the lumbar frame, and the lumbar support is provided with a lumbar frame strap through a groove.

9. A rope-driven hip joint exoskeleton for easy force transmission according to claim 1, characterized in that: The leg frame includes a double-layer carbon fiber plate and a leg guard. The upper end of the double-layer carbon fiber plate is fixedly connected to the lower side shaft connector, and the leg guard is fixedly installed on the lower inner side of the double-layer carbon fiber plate.

10. A rope-driven hip exoskeleton for facilitating force transmission according to claim 9, characterized in that: The upper and lower fixing components are fixedly installed between the double-layer carbon plates of the leg.

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