A torsion-resistant continuum robot actuator based on origami structure

Abstract

The present invention discloses an anti-torsion continuum robot actuator based on an origami structure, wherein the frame includes an upper and lower part arranged in a mirror image, an embedded rotating part is arranged in the frame, can realize multi-degree-of-freedom rotation, and is used to connect the upper and lower parts of the frame; an external foldable body is arranged on the periphery of the frame; a cable system is arranged in the frame and passes through the external foldable body, and is used to control and drive the frame, the external foldable body, and the embedded rotating part to rotate in multiple degrees of freedom. The present invention significantly improves the anti-torsion performance under load conditions, ensures the stability and precision of the actuator under complex motion conditions, and maintains the flexibility and lightweight characteristics of the continuum robot actuator.

Description

Technical Field

[0001] The invention relates to the field of robots and pipeline detection and maintenance, and in particular to an anti-torsion continuum robot actuator based on an origami structure. Background Art

[0002] Continuum Robots have gained wide attention in recent years in the fields of intelligent manufacturing, environmental testing, and deep-sea exploration due to their high flexibility and adaptability. Their lightweight and high-strength characteristics enable them to withstand multi-directional torque pressure, thereby completing complex movements without losing precision. Especially in operations that require high torsional rigidity, the actuator adapts to environmental pressure by deforming its geometric shape, significantly improving the reliability of the equipment. In the field of intelligent manufacturing, flexible actuators can be used for high-precision micro-assembly lines, such as the assembly of flexible electronic devices. In environmental monitoring, actuators can penetrate complex terrain (such as forests or mountains) to collect climate data and detect pollution sources through lightweight design and multi-degree-of-freedom movement. In the field of deep-sea exploration, the actuator's high torsional resistance can be used to cope with complex underwater fluid pressures, thereby completing seabed sample collection and equipment maintenance.

[0003] Unlike traditional rigid robotic arms, continuum robots achieve multi-degree-of-freedom movement through flexible structures and can flexibly move in narrow or complex environments. Therefore, they have great research value and practical application prospects in scenarios such as pipeline maintenance, industrial production, and search and rescue. However, traditional continuum robot actuators often deform or become unstable when subjected to external forces, especially under the influence of torsional forces. This deformation not only affects the robot's working accuracy, but may also reduce its range of motion and reduce the operating effect.

[0004] In order to solve the torsion problem of the actuator under load conditions, the prior art has proposed a variety of solutions. The first type of solution is to increase the structural stiffness of the actuator, such as using higher strength materials or reinforcing the internal structure. However, this type of method is usually accompanied by increased design complexity and weight, which limits the flexibility of the robot. Another solution is to introduce a universal joint to improve the multi-degree-of-freedom movement capability of the actuator, but the universal joint has a "universal joint lock" problem. When multiple rotation axes coincide, the movement capability of the actuator will be severely limited. In addition, some researchers have adopted a design that embeds a central rigid rod or fills with elastic materials to enhance torsion resistance, but these methods usually consume more driving energy, while weakening the advantages of the flexible structure and affecting the robot's movement flexibility in complex environments.

[0005] These limitations of existing technologies, especially the contradiction between improving torsion resistance and maintaining motion flexibility, have become the main obstacles to the development of continuum robots. Therefore, a new actuator design is urgently needed that can significantly enhance its torsion resistance while maintaining the actuator's light weight and flexibility. Summary of the invention

[0006] In view of the shortcomings of the prior art, the present invention proposes an anti-torsion continuum robot actuator based on an origami structure. By adopting an origami pattern and a magnetic ball joint, not only the anti-torsion ability of the actuator is enhanced, but also the universal joint lock problem is avoided, thereby expanding the degree of freedom and working range of the actuator, and further improving its performance in complex tasks.

[0007] The specific technical solutions are as follows:

[0008] An anti-torsion continuum robot actuator based on an origami structure comprises: a frame, an external foldable body, an embedded rotating member, and a cable system; the frame comprises an upper and lower part arranged in a mirror image, the embedded rotating member is arranged in the frame, can realize multi-degree-of-freedom rotation, and is used to connect the upper and lower parts of the frame; the external foldable body is arranged on the outer periphery of the frame; the cable system is arranged in the frame, and is used to control and drive the frame, the external foldable body, and the embedded rotating member to rotate;

[0009] The embedded rotating part includes: a magnetic ball joint, two piston rods, two bias springs, and two containing structures; one end of the containing structure is fixedly connected to the frame, and the bias spring and the piston rod are arranged in sequence in the containing structure, one end of the bias spring is against the wall of the containing structure, and the other end is against one end of the piston rod; the other end of the piston rod is connected to the magnetic ball joint, and the magnetic ball joint is adsorbed by magnetic force and realizes multi-degree-of-freedom rotation.

[0010] Furthermore, the magnetic ball joint includes a permanent magnet magnetic ball and a metal concave support, one end of the metal concave support is a concave surface, the concave surface is adapted to the spherical surface of the permanent magnet magnetic ball, and the other end is fixedly connected to one of the piston rods; the permanent magnet magnetic ball is adsorbed on the concave surface of the concave support by magnetic force and realizes rotational motion in three degrees of freedom; a connecting rod is coaxially fixed to the permanent magnet magnetic ball for being fixedly connected to another piston rod.

[0011] Further, the outer foldable body includes: dotted folds, connecting pins, connecting sockets, hollowing, and wiring holes;

[0012] When the external foldable body is folded, it is folded along the dotted folds, the hollowing is arranged at the intersection of the dotted folds, and the wiring holes are used for the cables of the cable system to pass through; the telescopic direction of the foldable body after folding is the main direction, and on both sides of each external foldable body perpendicular to the main direction, one side is evenly provided with a plurality of connecting pins, and the other side is evenly provided with a plurality of connecting sockets, and the connecting pins correspond to the connecting sockets one by one; the connecting pins are inserted into the connecting sockets to achieve connection, so as to enclose the external deformable flexible shell of the actuator, and the two ends of the main direction of the external deformable flexible shell are respectively fixedly connected to the two ends of the frame.

[0013] Furthermore, the external foldable body has multiple pieces, and the connecting pin of one folded external foldable body is inserted into the connecting socket of another folded external foldable body, and they are connected in sequence. All the external foldable bodies are connected end to end to form a column, which constitutes the external deformable flexible shell of the actuator.

[0014] Further, the cable system includes: four groups of cables, two capstans, and two brushless DC motors;

[0015] Two brushless DC motors are respectively fixed inside the upper and lower frames, a capstan is fixedly connected to the output shaft of each brushless DC motor, two groups of cables are wound around the capstan in opposite directions, the two groups of cables extend out of the capstan in opposite directions along the same diameter, the extended cables pass through the frame of the brushless DC motor, and are fixedly connected to the frame of the other part through an external foldable body; each brushless DC motor and the corresponding capstan and the two groups of cables wound thereon constitute a cable drive device; the plane where the two groups of cables corresponding to the upper cable drive device are located is perpendicular to the plane where the two groups of cables of the lower cable drive device are located.

[0016] Furthermore, the cable system is provided with an automatic tensioning mechanism to ensure that the total length of the two groups of cables in the same cable drive device remains unchanged and is always tensioned during the operation of the brushless DC motor.

[0017] Furthermore, the outer foldable main body material is any one of polyethylene terephthalate, polypropylene, polycarbonate, polyimide, polyethylene, and ethylene-vinyl acetate copolymer with a thickness of 0.15-0.35 mm.

[0018] Furthermore, the outer foldable body adopts any one of the Yoshimura origami structure, the Kresling origami structure and the Miura origami structure.

[0019] Furthermore, the embedded rotating part material is any one of aluminum alloy, ABS, carbon fiber composite material, titanium alloy, polyetheretherketone, magnesium alloy, polyamide, polyoxymethylene, and aramid fiber composite.

[0020] Furthermore, the upper part and the lower part of the frame both include a fixed disc and a hollow cylindrical shell, the hollow cylindrical shell is fixedly connected to the fixed disc, and the brushless DC motor of the cable system is arranged in the hollow cylindrical shell.

[0021] The beneficial effects of the present invention are:

[0022] (1) The origami-based torsion-resistant continuum robot actuator proposed in the present invention significantly improves the torsion-resistant performance under load conditions, ensures the stability and accuracy of the actuator under complex motion conditions, and maintains the flexibility and lightweight characteristics of the continuum robot actuator.

[0023] (2) Through the application of a variety of origami structures, the actuator of the present invention has a high efficiency anti-torsion capability and can flexibly adapt to different operating tasks.

[0024] (3) The lightweight and high-strength embedded rotating part design of the present invention ensures that the actuator has good lightweight characteristics and does not sacrifice its flexibility due to enhanced torsion resistance. The design of the magnetic ball joint not only solves the locking problem of traditional universal joints, but also improves the actuator's movement flexibility and accuracy through the self-calibration function.

[0025] (4) The present invention enables the actuator to have high-precision control capabilities in multi-degree-of-freedom motion through a cable system, and is suitable for a variety of complex environments such as medical surgery, industrial production, and rescue operations. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 1 is the design and actual picture of the anti-torsion continuum robot actuator based on origami structure in a normal state in an embodiment of the present invention, wherein (a) is the design drawing and (b) is the actual picture.

[0027] Figure 2 It is a schematic structural diagram of the external foldable main body in Example 1 of the present invention.

[0028] Figure 3 It is a physical schematic diagram of an external foldable body with three connected pieces in an embodiment of the present invention.

[0029] Figure 4 Schematic diagram of the structure of the embedded rotating part in the embodiment of the present invention.

[0030] Figure 5 Schematic diagram of the structure of a magnetic ball joint embedded in a rotating part in an embodiment of the present invention.

[0031] Figure 6 1 is a schematic diagram of the structure of the cable system in an embodiment of the present invention, wherein (a) is a schematic diagram of a single-side structure of the cable system, and (b) is a layout diagram of the entire cable system.

[0032] Figure 7 The figures are the design and actual picture of the anti-torsion continuum robot actuator based on origami structure in a torsion state in an embodiment of the present invention, wherein (a) is the design drawing and (b) is the actual picture.

[0033] In the figure, frame 1, external foldable body 2, dotted fold 2-1, connecting pin 2-2, connecting socket 2-3, hollow 2-4, wiring hole 2-5; embedded rotating part 3, magnetic ball joint 3-1, permanent magnet magnetic ball 3-1-1, metal concave support 3-1-2, piston rod 3-2, bias spring 3-3, accommodating structure 3-4; cable system 4, cable one 4-1, cable two 4-2, cable three 4-3, cable four 4-4, winch 4-5, brushless DC motor 4-6. DETAILED DESCRIPTION

[0034] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.

[0035] In the following description, reference is made to “one specific embodiment”, which describes a subset of all possible embodiments, but it can be understood that “one specific embodiment” describes the same subset or different subsets of all possible embodiments and can be combined with each other without conflict.

[0036] Unless otherwise defined, all technical science and technology used herein have the same meaning as commonly understood by those skilled in the art of the present invention. The terms used herein are only for the purpose of describing the embodiments of the present invention and are not intended to limit the present invention.

[0037] Before further describing the embodiments of the present invention in detail, the nouns and terms involved in the embodiments of the present invention are described. The nouns and terms involved in the embodiments of the present invention are subject to the following explanations.

[0038] (1) Yoshimura folding structure: refers to a folding method based on the Yoshimura origami pattern (also known as the Yoshimura crease model or diamond crease model). The Yoshimura origami pattern is an origami technique characterized by a stable geometric shape and high rigidity of the folded structure. This origami pattern can ensure that the surfaces between the creases will not bend or deform, such as tension or compression, during the folding process, so it is widely used in various engineering structures. The principle of the Yoshimura origami pattern is to use a specific folding method to form a series of interconnected triangular or diamond structures after folding. These structures can maintain a stable geometric shape during the folding and unfolding process, thereby providing high rigidity and strength.

[0039] like Figure 1 As shown, a torsion-resistant continuum robot actuator based on an origami structure comprises: a frame 1, an external foldable body 2, an embedded rotating member 3, and a cable system 4. The frame 1 is divided into two mirror-arranged upper and lower parts (also called upper and lower ends), each of which comprises a fixed disc and a hollow cylindrical shell, and the hollow cylindrical shell is fixedly connected to the fixed disc. The embedded rotating member 3 is arranged in the frame 1, which can realize multi-degree-of-freedom rotation and is used to connect the upper and lower parts of the frame 1; the cable system 4 is also arranged in the frame 1, which is used to control the rotation of the embedded rotating member 3; the external foldable body 2 is arranged on the outer periphery of the frame 1 to play a protective role, which provides high torsion resistance along the axial direction and can be bent in multiple directions.

[0040] like Figure 2 and Figure 3As shown, the external foldable body 2 has multiple pieces, each piece includes: a dotted fold 2-1, a connecting pin 2-2, a connecting socket 2-3, a hollow 2-4, and a wiring hole 2-5. When folding, the dotted fold 2-1 is followed, and the hollow 2-4 is arranged at the intersection of the dotted fold 2-1, so that the folding is easier, which is conducive to the timely deformation of the external foldable body 2 when the actuator is bent. The wiring hole 2-5 is used for the cables of the cable system 4 to pass through, and can reduce the weight of the structure, while increasing the flexibility and response speed of the actuator during movement. The telescopic direction of the external foldable body 2 after folding is recorded as the main direction. On the two sides of each external foldable body 2 perpendicular to the main direction, a plurality of connecting pins 2-2 are evenly arranged on one side, and a plurality of connecting sockets 2-3 are evenly arranged on the other side, and the connecting pins 2-2 correspond to the connecting sockets 2-3 one by one. When all the external foldable bodies 2 are folded, the connecting pin 2-2 of one external foldable body 2 is inserted into the connecting socket 2-3 of another external foldable body 2 in sequence, and finally all the external foldable bodies 2 are connected end to end to form a column, which constitutes the external deformable flexible shell of the actuator. The two ends of the main direction of the external deformable flexible shell are respectively fixed to the fixed disks at the two ends of the frame 1. The interlocking connection of multiple external foldable bodies 2 further improves the structural strength and torsion resistance of the actuator, and reduces the deformation of the actuator under load conditions. In this embodiment, the external foldable body 2 is made of three pieces, denoted as A, B, and C. After the three pieces are folded, the connecting pin 2-2 of A is inserted into the connecting socket 2-3 of B, the connecting pin 2-2 of B is inserted into the connecting socket 2-3 of C, and the connecting pin 2-2 of C is inserted into the connecting socket 2-3 of A, thereby forming a structure in which three pieces of external foldable bodies 2 are connected end to end, forming the external deformable flexible shell of the actuator.

[0041] Furthermore, the outer foldable body 2 is made of any one of polyethylene terephthalate (PET), polypropylene (PP), polycarbonate (PC), polyimide (PI), polyethylene (PE) or ethylene-vinyl acetate copolymer (EVA) materials with a thickness of 0.15-0.35 mm, and has light weight, high strength and good flexibility.

[0042] like Figure 4As shown, the embedded rotating part 3 includes: a magnetic ball joint 3-1, two piston rods 3-2, two bias springs 3-3, and two containing structures 3-4. The containing structure 3-4 is a hollow cylinder with one end open, and the unopened end is fixedly connected to the frame 1. The bias spring 3-3 and the piston rod 3-2 are arranged in the containing structure 3-4 in sequence. One end of the piston rod 3-2 is against the bias spring 3-3, and the other end is connected to the magnetic ball joint 3-1. The bias spring 3-3 structure located on both sides of the magnetic ball joint 3-1 ensures that the magnetic ball joint 3-1 moves stably at the geometric center position of the actuator, thereby reducing the influence of axial length changes on the movement. As the core of the actuator, the embedded rotating part 3 can effectively resist axial torsion while maintaining good bending characteristics. The design of the embedded rotating part 3 enables the actuator to maintain high-precision movement in a complex environment, and improves the flexibility of the actuator through the multi-degree-of-freedom movement of the magnetic ball joint 3-1.

[0043] like Figure 5 As shown, the magnetic ball joint 3-1 includes a permanent magnet magnetic ball 3-1-1 and a metal concave support 3-1-2. One end of the metal concave support 3-1-2 is a concave surface, which is matched with the spherical surface of the permanent magnet magnetic ball 3-1-1 and is coated with grease to reduce friction; the other end is fixedly connected to one of the piston rods 3-2, and in this embodiment, a detachable connection is adopted with the piston rod 3-2 below, and further, a threaded connection is adopted. The permanent magnet magnetic ball 3-1-1 is adsorbed on the concave surface of the concave support 3-1-2 by magnetic force, and can realize rotational motion in three degrees of freedom. A connecting rod is coaxially fixed to the permanent magnet magnetic ball 3-1-1 for being fixedly connected to another piston rod 3-2; in this embodiment, the connecting rod is detachably connected to the upper piston rod 3-2, and further, a threaded connection is adopted.

[0044] Furthermore, the embedded rotating part 3 is made of a lightweight and high-strength material, selected from any one of aluminum alloy, ABS, carbon fiber composite material, titanium alloy, polyetheretherketone (PEEK), magnesium alloy, polyamide (PA), polyoxymethylene (POM) or aramid fiber composite material, which can provide excellent strength, rigidity and durability while keeping the actuator light, so as to ensure its high-performance operation in complex environments.

[0045] like Figure 6 As shown, the cable system 4 includes: cable one 4-1, cable two 4-2, cable three 4-3, cable four 4-4, two capstans 4-5, and two brushless DC motors 4-6.

[0046] The two brushless DC motors 4-6 are fixed inside the frame 1 and are respectively located on both sides of the magnetic ball joint 3-1; a capstan 4-5 is fixedly connected to the output shaft of each brushless DC motor 4-6, and two sets of cables are wound on the capstan 4-5 in opposite directions, and the other end of the cable is fixed to the frame at the other end; each brushless DC motor 4-6 and the corresponding capstan 4-5 and the two sets of cables wound thereon constitute a cable drive device. The two cable drives are responsible for the bending movements of the actuator in the X-axis and Y-axis directions, respectively, and achieve precise bending movements through synchronous control. In addition, the cable system 4 is designed with an automatic tensioning mechanism. During operation, the total length of the two sets of cables in the same cable drive device remains unchanged, preventing the cables from loosening during movement, ensuring continuous cable tension and precise control.

[0047] Specifically, a cable 4-1 (i.e., Figure 6 The red line in the middle), is wound clockwise with cable 2 4-2 (i.e. Figure 6 The green line in the figure). The parts of cable 1 4-1 and cable 2 4-2 extending from the capstan 4-5 are symmetrical along the center of the capstan 4-5, and the extended parts pass through the fixed disc of the lower frame 1 (which plays a limiting role), and then pass through the wiring hole 2-5 of the external foldable body 2, and are fixedly connected to the fixed disc of the upper frame 1. The two fixed points are also symmetrical along the center of the fixed disc. The capstan 4-5 fixedly connected to the output shaft of the upper brushless DC motor 4-6 is wound counterclockwise with cable 3 4-3 (i.e. Figure 6 The blue wire in the middle), there are four cables 4-4 wound clockwise (i.e. Figure 6 The portions of cable three 4-3 and cable four 4-4 extending from the capstan 4-5 are symmetrical along the center of the capstan 4-5, and the extended portions pass through the fixed disc of the upper end frame 1 (which serves as a limit), and then pass through the wiring hole 2-5 of the external foldable body 2 to be fixedly connected to the fixed disc of the lower end frame 1, and the two fixing points are also symmetrical along the center of the fixed disc.

[0048] The line connecting the fixed points of cable three 4-3 and cable four 4-4 on the lower fixed disk is orthogonal to the line connecting the fixed points of cable one 4-1 and cable two 4-2 on the upper fixed disk; the direction of the line connecting the fixed points of cable three 4-3 and cable four 4-4 on the lower fixed disk is recorded as the X direction, and the direction of the line connecting the fixed points of cable one 4-1 and cable two 4-2 on the upper fixed disk is recorded as the Y direction. When the lower brushless DC motor 4-6 runs clockwise, cable one 4-1 contracts and cable two 4-2 extends, driving the frame 1 to rotate around the X axis (i.e., to Figure 6 The structure of the actuator is as follows: Figure 7On the contrary, when the lower brushless DC motor 4-6 runs counterclockwise, the cable 1 4-1 stretches and the cable 2 4-2 contracts, driving the frame 1 to rotate around the X-axis (i.e. Figure 6 When the upper brushless DC motor 4-6 runs clockwise, the cable 3 4-3 contracts and the cable 4 4-4 extends, driving the frame 1 to rotate around the Y axis (i.e., to the right). Figure 6 On the contrary, when the lower brushless DC motor 4-6 runs counterclockwise, the cable 3 4-3 stretches and the cable 4 4-4 contracts, driving the frame 1 to rotate around the Y axis (i.e., to Figure 6 mid-rearward rotation). Example 1

[0049] like Figure 2 and Figure 3 As shown, the external foldable body 2 of the actuator adopts a Yoshimura origami structure, that is, the dotted fold 2-1 follows the folding method of the Yoshimura origami pattern, and the connecting pins 2-2 of the three external foldable bodies 2 are inserted into the connecting sockets 2-3 of another external foldable body 2 in sequence to realize the finishing connection of the three origami structures, and merge into the external deformable flexible shell of the actuator. The Yoshimura origami structure is arranged by a number of interconnected triangular units, which can provide efficient torsion resistance in the axial direction. The triangular units of the origami structure have high rigidity and can effectively prevent distortion and instability under external forces. The magnetic ball joint 3-1 embedded in the frame 1 ensures that the actuator can rotate freely without distortion when subjected to external forces. This design enables the actuator to maintain high-precision movement in complex environments, and improves the flexibility of the actuator through the multi-degree-of-freedom movement of the magnetic ball joint 3-1.

[0050] The outer foldable body 2 is made of 0.25mm thick PET material, which has excellent flexibility and durability and can withstand multiple folding and high-frequency movement. At the same time, the embedded rotating part 3 is made of ABS consumables through 3D printing technology, ensuring the lightweight and high strength of the structure. Example 2

[0051] The external foldable body 2 of the actuator adopts a Kresling origami structure, that is, the dotted fold 2-1 follows the folding method of the Kresling origami pattern. The structure is composed of multiple annular folding units, which are arranged in a spiral manner to form a structure with torsion resistance and compression resistance. The unique design of the Kresling structure enables it to remain stable when torsional force is applied, while adapting to different load requirements through axial expansion and compression. The structure has high torsional rigidity and can effectively resist torsional stress from different directions. The actuator is embedded in the combination of the rotating part 3 and the cable system 4 to achieve the ability to freely restore the initial state under the action of external force, ensuring that the structure does not undergo unnecessary deformation during movement.

[0052] The materials selected for the outer foldable body 2 and the embedded rotating member 3 are consistent with those in the first embodiment. Example 3

[0053] The external foldable body 2 of the actuator adopts the Miura origami structure, that is, the dotted fold 2-1 follows the folding method of the Miura origami pattern. The structure is formed by folding multiple diamond-shaped units, which can achieve good axial expansion and torsion resistance. The Miura folding structure not only has high flexibility, but also can effectively prevent distortion when subjected to external force. It is suitable for application scenarios that require high flexibility. The structure can achieve different deformation modes by adjusting the folding angle, which enhances the adaptability of the actuator. In conjunction with the embedded rotating part 3 and the cable system 4, the Miura origami structure can remain stable under high load conditions and provide multi-degree-of-freedom movement through the magnetic ball joint 3-1.

[0054] The materials selected for the outer foldable body 2 and the embedded rotating member 3 are consistent with those in the first embodiment.

[0055] The present invention proposes a new solution to the problem that traditional continuum robot actuators are prone to twisting, deformation and unstable movement under the action of external forces. Existing continuum robot actuators are difficult to maintain stable and precise operation under high load or complex motion scenarios due to the lack of sufficient anti-torsion ability. In particular, in medical surgery and industrial production and other occasions where high motion stability is required, traditional designs are difficult to meet the requirements. Although universal joints can provide multi-degree-of-freedom movement, there is a "universal joint lock" phenomenon, which limits the freedom of movement of the actuator. In addition, existing solutions such as increasing the stiffness of the actuator and increasing the weight of the structure, although improving the torsional performance, often sacrifice the flexibility and lightweight design of the robot. Therefore, the present invention aims to provide an actuator that can significantly improve the torsional resistance while maintaining the lightweight and high flexibility of the actuator.

[0056] The torsion-resistant continuum robot actuator based on origami structure proposed in the present invention can adopt Yoshimura origami structure, Kresling origami structure, Miura origami structure and other origami schemes to make the external foldable body 2. These structures provide efficient torsion resistance through geometric folding, and can maintain the structural stability of the actuator under load. The core component of the actuator is the embedded rotating part 3. The design of the magnetic ball joint 3-1 can realize free rotation in three degrees of freedom, avoiding the "locking" problem of the traditional universal joint, and self-calibrating through the magnetic force field, and can automatically return to the initial position after the external force disappears. The actuator is driven by two brushless DC motors 4-6, and the bending and rotation of the frame 1, the external foldable body 2 and the embedded rotating part 3 in different directions are controlled by the cable system 4 to adapt to different operating environments and task requirements. The cable system 4 is also designed with an automatic tensioning mechanism to ensure that the cable is always kept tight during the movement of the actuator to prevent relaxation from causing movement failure. This design enables the actuator to maintain high-precision movement in complex environments, and is suitable for various complex application scenarios such as pipeline inspection and maintenance machines.

[0057] It should be noted that, in this article, the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the sentence "comprises a ..." does not exclude the existence of other identical elements in the process, method, article or device including the element.

[0058] The above description is only the preferred embodiment of the present invention, which enables those skilled in the art to understand or implement the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various changes and variations, and the various modifications to these embodiments will be obvious to those skilled in the art. The general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention shall be included in the protection scope of the present invention.

Claims

1. A torsion-resistant continuum robot actuator based on origami structure, characterized in that: include: A frame, an external foldable body, an embedded rotating member, and a cable system; the frame includes an upper and lower part arranged in a mirror image, the embedded rotating member is arranged in the frame, can realize multi-degree-of-freedom rotation, and is used to connect the upper and lower parts of the frame; the external foldable body is arranged on the outer periphery of the frame; The cable system is arranged in the frame and is used to control and drive the frame, the external foldable body, and the embedded rotating member to rotate; The embedded rotating member comprises: a magnetic ball joint, two piston rods, two bias springs, and two containing structures; one end of the containing structure is fixedly connected to the frame, and the bias spring and the piston rod are arranged in the containing structure in sequence, one end of the bias spring abuts against the wall of the containing structure, and the other end abuts against one end of the piston rod; the other end of the piston rod is connected to the magnetic ball joint, and the magnetic ball joint is adsorbed by magnetic force and realizes multi-degree-of-freedom rotation; The cable system includes: four sets of cables, two capstans, and two brushless DC motors; Two brushless DC motors are respectively fixed inside the upper and lower frames, a capstan is fixedly connected to the output shaft of each brushless DC motor, two groups of cables are wound around the capstan in opposite directions, the two groups of cables extend out of the capstan in opposite directions along the same diameter, the extended cables pass through the frame of the brushless DC motor, and are fixedly connected to the frame of the other part through an external foldable body; each brushless DC motor and the corresponding capstan and the two groups of cables wound thereon constitute a cable drive device; the plane where the two groups of cables corresponding to the upper cable drive device are located is perpendicular to the plane where the two groups of cables of the lower cable drive device are located.

2. The origami-structured torsion-resistant continuum robot actuator according to claim 1, characterized in that: The magnetic ball joint includes a permanent magnet magnetic ball and a metal concave support. One end of the metal concave support is a concave surface that matches the spherical surface of the permanent magnet magnetic ball, and the other end is fixedly connected to one of the piston rods. The permanent magnet magnetic ball is adsorbed on the concave surface of the concave support by magnetic force and realizes rotational motion in three degrees of freedom. A connecting rod is coaxially fixedly connected to the permanent magnet magnetic ball for being fixedly connected to another piston rod.

3. The origami-based torsion-resistant continuum robot actuator according to claim 1, characterized in that: The outer foldable body includes: dotted folds, connecting pins, connecting holes, hollows, and wiring holes; When the external foldable body is folded, it is folded along the dotted folds, the hollowing is arranged at the intersection of the dotted folds, and the wiring holes are used for the cables of the cable system to pass through; the telescopic direction of the foldable body after folding is the main direction, and on both sides of each external foldable body perpendicular to the main direction, one side is evenly provided with a plurality of connecting pins, and the other side is evenly provided with a plurality of connecting sockets, and the connecting pins correspond to the connecting sockets one by one; the connecting pins are inserted into the connecting sockets to achieve connection, so as to enclose the external deformable flexible shell of the actuator, and the two ends of the main direction of the external deformable flexible shell are respectively fixedly connected to the two ends of the frame.

4. The origami-based torsion-resistant continuum robot actuator according to claim 3, characterized in that: The external foldable body has multiple pieces, and the connecting pin of one folded external foldable body is inserted into the connecting socket of another folded external foldable body, and they are connected in sequence. All the external foldable bodies are connected end to end to form a column, which constitutes the external deformable flexible shell of the actuator.

5. The origami-structured torsion-resistant continuum robot actuator according to claim 1, characterized in that: The cable system is provided with an automatic tensioning mechanism to ensure that the total length of two groups of cables in the same cable drive device remains unchanged and is always tensioned during the operation of the brushless DC motor.

6. The origami-structured torsion-resistant continuum robot actuator according to claim 1, characterized in that: The outer foldable main body material is any one of polyethylene terephthalate, polypropylene, polycarbonate, polyimide, polyethylene, and ethylene-vinyl acetate copolymer with a thickness of 0.15-0.35 mm.

7. The origami-structured torsion-resistant continuum robot actuator according to claim 1, characterized in that: The external foldable body adopts any one of the Yoshimura origami structure, the Kresling origami structure and the Miura origami structure.

8. The origami-structured torsion-resistant continuum robot actuator according to claim 1, characterized in that: The embedded rotating part is made of any one of aluminum alloy, ABS, carbon fiber composite material, titanium alloy, polyetheretherketone, magnesium alloy, polyamide, polyoxymethylene, and aramid fiber composite.

9. The origami-structured torsion-resistant continuum robot actuator according to claim 1, characterized in that: The upper part and the lower part of the frame both include a fixed disc and a hollow cylindrical shell, the hollow cylindrical shell is fixedly connected to the fixed disc, and the brushless DC motor of the cable system is arranged in the hollow cylindrical shell.

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