Exoskeleton binding structure based on constant force spring

Abstract

The invention relates to an exoskeleton binding structure based on constant-force springs, in the structure, a front side constant-force spring suspension assembly and a rear side constant-force spring suspension assembly are pasted and fixed on a front position and a rear position of the side surface of a waist assembly; the knee joint exoskeleton leg assembly is connected to the front side constant force spring suspension assembly and the rear side constant force spring suspension assembly through Y-shaped hip belts. The front-side constant-force spring suspension assembly and the rear-side constant-force spring suspension assembly can counteract the size deviation, caused by human body movement, of a waist belt and legs through extension and shortening of springs in the exoskeleton wearing and moving process, and continuously apply constant-size and always-upward tensile force, the tensile force directly acts on the knee joint exoskeleton leg assembly, and the knee joint exoskeleton leg assembly can be used for fixing the knee joint exoskeleton leg assembly. The self weight of the knee joint exoskeleton leg assembly can be dynamically balanced, the knee joint exoskeleton leg assembly is prevented from falling or shifting, and it is ensured that the exoskeleton is always kept at the preset wearing position.

Description

Technical Field

[0001] This invention relates to a flexible binding mechanism for an exoskeleton robot, and more particularly to an exoskeleton binding structure based on a constant force spring, belonging to the field of exoskeleton robot technology. Background Technology

[0002] Knee exoskeletons are increasingly used in rehabilitation medicine and industrial assistive devices. However, in practical use, problems such as overall slippage or displacement due to the device's own weight, motion inertia, and human-machine interface mismatch are common. This problem not only seriously affects the stability of the assistive effect and the comfort of the user experience, but may also pose potential safety risks. Existing solutions for preventing slippage mainly focus on methods such as strap fixation, bionic structures, and external support, but all of them have obvious limitations.

[0003] Regarding strap fixation, traditional rigid or single-point straps are difficult to adapt to changes in the musculoskeletal morphology of the human body during movement, easily causing localized pressure concentration and equipment slippage. Although there are improved solutions, such as the patent "An Exoskeleton" (CN111329665A, publication date 2020-06-26) which proposes using elastic material waist straps combined with strap components arranged in the thigh area to improve force distribution, its design faces significant challenges: the mechanical properties of the elastic straps are difficult to precisely match the anti-fall requirements. If the elastic modulus of the material is too high, it approximates a rigid restraint, causing the user to suffer greater uncomfortable pressure; if the elasticity is too weak, it cannot provide sufficient restraint to resist falling.

[0004] In terms of structural biomimetic optimization, the patent "Lower Limb Exoskeleton Robot and Its Bionic Knee Joint Mechanism" (CN211675179U, publication date 2020-10-16) places the rotation center of the exoskeleton's knee joint rearward to better align with the physiological joint axis of the human body, thereby reducing interference torque and indirectly alleviating device sinking. However, such biomimetic alignment mechanisms are often relatively complex and have poor adaptability to users of different body types, making it difficult to maintain ideal alignment and anti-fall performance in widespread applications.

[0005] In search of solutions, some designs have shifted towards external support structures. For example, the patent "A Stabilizing Lower Limb Exoskeleton Rehabilitation Equipment" (CN215821911U, publication date 2023-05-12) uses an auxiliary rod with casters to form a triangular support with the waist, thereby distributing the load between the equipment and the user. While this method can effectively suppress falls, it comes at the cost of sacrificing the system's portability and mobility, limiting its feasibility for application in various scenarios.

[0006] In summary, existing fall protection technologies are either limited by material and control challenges, constrained by structural complexity and insufficient adaptability, or forced to compromise on system portability and flexibility. Therefore, there is an urgent need in this field for a novel fall protection solution that is structurally simple and reliable, easy to control, and can balance good wearability and freedom of movement. Summary of the Invention

[0007] The technical problem solved by this invention is to overcome the defects of existing exoskeleton binding structures, such as easy falling, poor comfort, and insufficient adaptability, and to provide an exoskeleton binding structure based on a constant force spring, which can provide a continuous and stable upward lifting force for the exoskeleton system, effectively resist the device falling due to gravity and inertia, thereby significantly improving the stability and comfort of wearing it.

[0008] The solution of this invention is: an exoskeleton binding structure based on constant force springs, the structure comprising a waist assembly, a front constant force spring suspension assembly, a rear constant force spring suspension assembly, a Y-shaped hip strap, and a knee joint exoskeleton leg assembly; wherein:

[0009] The front constant force spring suspension assembly and the rear constant force spring suspension assembly are glued and fixed to two positions on the side of the waist assembly, slightly forward and slightly backward.

[0010] The knee exoskeleton leg component is connected to the front constant force spring suspension component and the rear constant force spring suspension component via a Y-shaped hip belt;

[0011] The front and rear constant force spring suspension components can compensate for the size deviation between the waist belt and legs caused by human movement during the wearing and movement of the exoskeleton by the extension and shortening of the springs, and continuously apply a constant force that is always upward. This force acts directly on the knee joint exoskeleton leg component, which can dynamically balance the weight of the knee joint exoskeleton leg component, prevent the knee joint exoskeleton leg component from falling or shifting, and ensure that the exoskeleton always maintains the preset wearing position.

[0012] Preferably, the front constant force spring suspension assembly and the rear constant force spring suspension assembly are fixed to the waist assembly by Velcro.

[0013] Preferably, the lower end of the Y-shaped hip belt has an adjustable webbing buckle at the connection point with the knee exoskeleton leg assembly.

[0014] Preferably, the included angle of the Y-shaped hip belt is α, which can be adjusted within a range of 15°-60°.

[0015] Preferably, the front constant force spring suspension assembly and the rear constant force spring suspension assembly have the same structure, including a bracket, two constant force springs, an output shaft, two fixing screws and a webbing reel;

[0016] The bracket consists of a back plate and four parallel panels perpendicular to the back plate. The four parallel panels form three slots with each other. The output shaft passes through the through hole in the middle of the four panels and is fixed at both ends by fixing screws. Two constant force springs are located in the slots on both sides. The inner ring is fixed to the output shaft by screws, while the outer ring is fixed to the bracket to form a rigid connection. The output shaft rotates under the drive of the constant force springs, causing the constant force springs to deform accordingly. The webbing roller is located in the middle slot and is fixed to the output shaft by a pin.

[0017] Preferably, the material is made of 6061 aluminum alloy.

[0018] Preferably, when the distance between the leg structure and the waistband increases, the constant force spring rotates to drive the webbing reel to rotate clockwise to release the webbing, which automatically adapts to the length of the waist and legs; when the distance decreases, the constant force spring rotates counterclockwise to retract, which drives the webbing reel to rotate and retract the webbing to ensure constant tension.

[0019] Preferably, the webbing reel is connected to the Y-shaped hip belt via an adjusting buckle.

[0020] The beneficial effects of this invention compared to the prior art are:

[0021] (1) This invention proposes a constant-force spring binding and fixing scheme, which integrates a set of constant-force spring suspension components at the hip belt connection point between the waist belt and the leg hip belt structure of the exoskeleton. This component can compensate for dimensional deviations between the waist belt and legs caused by human movement during exoskeleton wearing and movement by extending and shortening the springs, and continuously apply a basically constant tensile force that is always upward. This tensile force acts directly on the exoskeleton leg components, dynamically balancing the exoskeleton's own weight, thereby fundamentally preventing the device from falling or shifting, and ensuring that the exoskeleton always remains in the preset wearing position.

[0022] (2) This invention proposes a Y-shaped bifurcated hip belt layout. The upper end of the hip belt is connected to the constant force spring bases on both sides of the waist belt, while the lower end is divided into two strands, which are fixed to the front and back sides of the thigh straps, respectively. This design can efficiently distribute the concentrated pulling force from the legs to the front and back sides of the waist belt, effectively avoiding the problem of the waist belt sagging on the side caused by the traditional single-point connection pulling force acting directly on the side, and significantly improving the overall wearing comfort and load-bearing capacity.

[0023] (3) This invention designs an adjustable modular fixing structure. The connection base between the constant force spring and the waist belt assembly is designed as an independent module, allowing it to be physically separated from the waist belt body. The hip belt system can be quickly assembled and disassembled using Velcro, improving the wearing efficiency of the exoskeleton device and its adaptability to different users. Attached Figure Description

[0024] Figure 1 This is a structural diagram of the exoskeleton based on a constant force spring in an embodiment of the present invention;

[0025] Figure 2 This is an assembly drawing of the constant force spring suspension assembly in an embodiment of the present invention. Detailed Implementation

[0026] The present invention will be further described below with reference to the embodiments.

[0027] Example 1

[0028] like Figure 1 As shown, this invention proposes an exoskeleton binding structure based on constant force springs, comprising a waist assembly 101, a front constant force spring suspension assembly 102, a rear constant force spring suspension assembly 103, a Y-shaped hip belt 104, and a knee joint exoskeleton leg assembly 105. The waist assembly 101 includes the exoskeleton's main controller, battery, and connecting cables, among other electrical components, which are integrated into the waist belt to ensure wearing comfort. The knee joint exoskeleton leg assembly includes the exoskeleton's thigh rod, calf rod, joint module, and structural components such as the leg lining and binding. A fixing buckle is attached to the upper side of the leg assembly via screws, connecting it to the lower end of the Y-shaped hip belt.

[0029] The front constant force spring suspension assembly 102 and the rear constant force spring suspension assembly 103 are fixed to the waist assembly 101 at two positions slightly forward and slightly backward on the side using Velcro. The upper end of the Y-shaped hip belt 104 is connected to the output shafts of the front constant force spring suspension assembly 102 and the rear constant force spring suspension assembly 103 respectively, and the lower end is fixed to the leg assembly 105 of the knee exoskeleton, dispersing the tension exerted by the leg assembly 105 on the waist assembly 101. The lower end of the Y-shaped hip belt is designed with an adjustable webbing length D-ring buckle, which can adjust the initial length of the webbing to ensure the pre-tension of the constant force spring in the initial state. It can also prevent the adjustment buckle from loosening when disassembling the exoskeleton, making it easy to remove the exoskeleton. The front constant force spring suspension assembly 102 and the rear constant force spring suspension assembly 103 can be attached to different positions on the waist belt assembly to ensure the adaptability of different exoskeletons to different body types. At the same time, the angle of the Y-shaped hip belt can be adjusted to improve the stress distribution of the waist belt. By using two fixed points at the front and rear, the force on the lumbar component 101 can be distributed to both the front and rear sides. The included angle of the Y-shaped hip belt is defined as α, with an adjustable range of approximately 15°-60°. The force on the lower end of the Y-shaped hip belt is F, then the force on the branch of the Y-shaped hip belt is... The lateral forces exerted by the Y-shaped hip belt 104 on the waist belt assembly 101 are canceled out from the front and back, so the single-point force on the waist belt assembly is... Traditional single-hip belts apply the force F directly to the waist connection point. The Y-shaped hip belt, compared to a single-hip belt, reduces the single-point force by half, preventing the waist component 101 from sagging under lateral force. Simultaneously, by varying the spring travel, the tension on the waist belt component 101 remains constant throughout the entire movement, not changing with leg movement, thus improving the stability of the waist component 101 in connection with the body.

[0030] like Figure 2 As shown, the constant force spring suspension assembly proposed in this invention mainly consists of core components such as a bracket 201, two constant force springs 202, an output shaft 203, two fixing screws 204, and a webbing reel 205. These components work together to achieve the function of constant force output. The bracket 201, as a basic structural component, is mainly used to fix and support the entire suspension assembly. It is made of high-quality 6061 aluminum alloy, possessing high strength and corrosion resistance, and capable of withstanding large loads. The rear side of the bracket 201 is fixed to the hook and loop fastener surface with adhesive. This fixing method is not only reliable but also facilitates later maintenance and replacement. The hook and loop fastener surfaces are glued to the corresponding hook and loop fastener surfaces on the waist component 101. A large area of ​​hook and loop fasteners is arranged on the sides of the waist component, which enhances the contact surface and provides easy adjustment. The fixing position can be flexibly selected according to different user needs to meet personalized requirements.

[0031] The bracket 201 consists of a back plate and four parallel panels perpendicular to the back plate. The four parallel panels form three slots with each other. The output shaft 203 passes through the through hole in the middle of the four panels and is fixed at both ends by fixing screws. Two constant force springs 202 are located in the slots on both sides respectively, and the webbing roller 205 is located in the middle slot.

[0032] The constant force spring 202 is one of the core components of this invention. Its inner ring is fixed to the output shaft 203 by screws, while its outer ring is fixed relative to the bracket 201, forming a rigid connection. The output shaft 203 rotates under the drive of the constant force spring 202, causing the spring to deform accordingly. The constant force spring 202 is a standard elastic element that can maintain an almost constant tensile force output over a large deformation range, a characteristic difficult to achieve in traditional springs. The core principle of the constant force spring lies in its unique geometric design, which ensures that the elastic force of each segment remains essentially constant during compression or tension. Specifically, the constant force spring design employs a variable-angle turn design, meaning the turn angle of the spring gradually increases with compression, thereby ensuring a constant contribution of elastic force to each segment. This design not only improves the spring's service life but also ensures the stability of the system output.

[0033] The roller 205 is fixed to the output shaft 203 with high-strength pins to ensure reliability and accuracy during transmission. The webbing reel 205 is connected to the Y-shaped hip belt 104 via an adjusting buckle, forming a closed-loop structure to achieve constant force output. This connection method not only facilitates adjustment but also allows for flexible adjustment of length and tightness according to the needs of different wearers.

[0034] In actual wear, the user first needs to put on the waist component 101 and leg component 105, and adjust the waist belt to a suitable length to ensure the stability of the overall structure. Next, the user needs to loosen the adjustment buckle of the Y-shaped hip belt to facilitate subsequent fixation. Then, the front constant force spring suspension component 102 and the rear constant force spring suspension component 103 are attached to the front and rear sides of the waist belt using Velcro, ensuring symmetrical placement on both sides. The attachment position can be manually adjusted to ensure comfort, and the contact surfaces must be clean and flat to guarantee reliable attachment. After fixation, the adjustment buckle is tightened, and the constant force springs are pulled up to provide a certain pre-tension to ensure the initial stability of the system. Finally, the connection between the webbing reel and the Y-shaped hip belt 104 applies an upward lifting force to the exoskeleton leg components, thereby achieving effective support and stability for the legs. This design ensures both system adjustability and user comfort and ease of use.

[0035] During use, users can adjust the belt length and Velcro fastening position according to their specific needs to achieve optimal support. Simultaneously, the constant tension characteristic of the constant force spring provides stable support during exercise, reducing unnecessary pressure on the legs and improving athletic performance and comfort. During walking, because the human body and exoskeleton cannot perfectly adapt, the distance between the belt and leg components changes periodically. When the distance between the leg structure and the belt increases, the constant force spring 202 rotates, causing the webbing reel 205 to rotate clockwise to release the webbing, automatically adapting to the length of the waist and legs. When the distance decreases, the constant force spring 202 rotates counterclockwise to retract, causing the webbing reel 205 to rotate and retract the webbing to maintain constant tension.

[0036] Compared with the prior art, the present invention has at least the following beneficial effects:

[0037] (1) The exoskeleton binding structure based on constant force springs can provide a stable and continuous support structure compared to elastic webbing structure, which can effectively prevent the exoskeleton from falling, improve the comfort of wearing and the assistive effect.

[0038] (2) The exoskeleton binding structure based on constant force springs can effectively reduce the tension on the waist and shoulders compared to rigid straps. The elasticity of the constant force springs allows for dynamic adjustment of the distance between the waist and leg components, avoiding the pulling phenomenon on the waist belt and shoulders during walking.

[0039] (3) The structure is simple and easy to implement, and has a small size. Through modular design, it can be quickly transplanted to the knee exoskeleton without affecting the normal use of the exoskeleton and walking.

[0040] This invention has the following implementation example, using a 170kg, 60kg adult male as the user. The weight of one leg structure of the exoskeleton is approximately 700g. To ensure sufficient tension to prevent the exoskeleton from sagging, a constant force spring with a tension of 15N is selected, and the selected model is LCF 040 12 100S. Therefore, during the entire exercise, the belt bears a downward tension of 30N.

[0041] Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make possible changes and modifications to the technical solutions of the present invention by utilizing the methods and techniques disclosed above without departing from the spirit and scope of the present invention. Therefore, any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solutions of the present invention shall fall within the protection scope of the technical solutions of the present invention.

Claims

1. An exoskeleton restraint structure based on a constant force spring, characterized in that... Includes a lumbar support assembly (101), a front constant-force spring suspension assembly (102), a rear constant-force spring suspension assembly (103), a Y-shaped hip belt (104), and a knee exoskeleton leg assembly (105); wherein: The front constant force spring suspension assembly (102) and the rear constant force spring suspension assembly (103) are glued and fixed to the front and rear sides of the waist assembly (101); The knee exoskeleton leg assembly (105) is connected to the front constant force spring suspension assembly (102) and the rear constant force spring suspension assembly (103) via a Y-shaped hip belt (104); The front constant force spring suspension assembly (102) and the rear constant force spring suspension assembly (103) can offset the size deviation between the waist belt and the legs caused by human movement through the extension and shortening of the springs during the wearing and movement of the exoskeleton, and continuously apply a constant force that is always upward. This force acts directly on the knee joint exoskeleton leg assembly (105), which can dynamically balance the weight of the knee joint exoskeleton leg assembly (105), prevent the knee joint exoskeleton leg assembly (105) from falling or shifting, and ensure that the exoskeleton is always maintained in the preset wearing position.

2. The exoskeleton binding structure based on a constant force spring according to claim 1, characterized in that, The front constant force spring suspension assembly (102) and the rear constant force spring suspension assembly (103) are fixed to the waist assembly (101) by Velcro.

3. The exoskeleton binding structure based on a constant force spring according to claim 1, characterized in that, The lower end of the Y-shaped hip belt has a D-ring buckle that allows for adjustable webbing length at the connection point with the knee exoskeleton leg assembly (105).

4. The exoskeleton binding structure based on a constant force spring according to claim 1, characterized in that, The included angle of the Y-shaped hip belt is α, and its adjustable range is 15°-60°.

5. The exoskeleton binding structure based on a constant force spring according to claim 1, characterized in that, The front constant force spring suspension assembly (102) and the rear constant force spring suspension assembly (103) have the same structure, including a bracket (201), two constant force springs (202), an output shaft (203), two fixing screws (204) and a webbing roller (205); The bracket (201) consists of a back plate and four parallel panels perpendicular to the back plate. The four parallel panels form three slots with each other. The output shaft (203) passes through the through hole in the middle of the four panels and is fixed at both ends by fixing screws. Two constant force springs (202) are located in the slots on both sides respectively. The inner ring is fixed to the output shaft (203) by screws, and the outer ring is fixed relative to the bracket (201) to form a rigid connection. The output shaft (203) rotates under the drive of the constant force springs (202), causing the constant force springs (202) to deform accordingly. The webbing roller (205) is located in the middle slot and is fixed to the output shaft (203) by pins.

6. The exoskeleton binding structure based on a constant force spring according to claim 5, characterized in that, The material is selected to be 6061 aluminum alloy.

7. The exoskeleton binding structure based on a constant force spring according to claim 5, characterized in that, When the distance between the leg structure and the waistband increases, the constant force spring (202) rotates and drives the webbing reel to rotate clockwise to release the webbing, which automatically adapts to the length of the waist and legs; when the distance decreases, the constant force spring 202 rotates counterclockwise to retract and drives the webbing reel (205) to rotate and retract the webbing to ensure constant tension.

8. The exoskeleton binding structure based on a constant force spring according to claim 5, characterized in that, The webbing reel (205) is connected to the Y-shaped hip belt (104) via an adjustment buckle.

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