Scalable tensegrity robot suitable for narrow terrain

Abstract

The invention discloses a scalable tensegrity robot suitable for narrow terrains, which comprises six multi-section electric push rods and twenty-four traction cables, two ends of each electric push rod are provided with reverse winding type constant force springs, one end of each traction cable is connected with the corresponding spring, the electric push rods stretch out and draw back to drive the traction cables to stretch out and draw back, and the traction cables stretch out and draw back to drive the robot to stretch out and draw back. Therefore, scaling of the robot is achieved. According to the scalable tensegrity robot suitable for the narrow terrain, the characteristics of long forced stroke and small tension change of the constant-force spring are utilized, so that the internal prestress of the robot is not changed in the scaling and moving process, and the influence of cable loosening and cable snapping on the structural stability is also greatly reduced. In addition, the gravity center of the robot can be changed by independently controlling the push rod, and rolling motion is achieved. The robot solves the problem that the robot is not easy to pass through narrow terrains (pipe galleries, variable cross-section water channels and the like), and the walking efficiency is greatly improved.

Description

Technical Field

[0001] The present invention relates to tensegrity robots, and particularly to a scalable tensegrity robot suitable for narrow terrains. Background Art

[0002] Tensegrity structures have received extensive attention from domestic and foreign scholars and engineers due to their characteristics such as light weight, self-adaptability, self-balancing, and flexible deployability. In recent years, they have been diversely developed and applied in different disciplinary fields such as aerospace deployable structures, functional materials, biomechanics, intelligent robots, and nanomaterials, and are known as the "structural system of the future". In addition, sensors and other instruments can be equipped for the robot to perform tasks of exploring the surface of a planet, collecting planet information data, and can play an important role in disaster rescue such as earthquakes and debris flows, with great social benefits.

[0003] However, there are still some problems with current tensegrity robots: For example, compared with other traditional structural systems, the structure of a tensegrity robot usually only uses two unit attributes of compression bars and cables. However, its body shape and size are fixed when assembled. When encountering narrow areas such as water channels and pipelines during movement, it performs extremely poorly, and it needs to detour, greatly slowing down the robot's traveling speed and causing considerable obstacles to the design of the robot's walking route. In addition, the springs used in conventional robots cannot ensure the constancy of the internal forces of the tension and compression members during deformation, and it is extremely easy to have the phenomenon that the pulling cable breaks due to excessive stress, or the cable becomes slack due to too small stress, resulting in the instability of the structure during movement.

[0004] To solve the above problems, this case is thus born. Summary of the Invention

[0005] (1) Technical Problems to be Solved

[0006] Aiming at the deficiencies of the prior art, the present invention provides a scalable tensegrity robot suitable for narrow terrains, solving the problems raised in the above background art.

[0007] (2) Technical Solutions

[0008] To achieve the above objectives, the present invention is realized through the following technical solutions: A scalable tensegrity robot suitable for narrow terrains includes: six multi-joint electric push rods and twenty-four pulling cables connecting them to each other, and the multi-joint electric push rods and the pulling cables together form an icosahedron spherical structure;

[0009] Both ends of each multi-joint electric push rod are provided with connecting cylinders and connected by bolts;

[0010] Each of the pulling cables is connected to a reverse-winding constant-force spring mechanism inside the connecting cylinder, which is used to ensure that the prestress inside the pulling cable remains constant during the movement of the robot.

[0011] By remotely controlling the telescopic movement of the multi-section electric push rod to drive the operation of the reverse-winding constant-force spring mechanism, the scaling and movement functions of the tensegrity robot can be realized.

[0012] Preferably, the multi-section electric push rod is remotely controllable, and bolts are provided at both ends thereof for fixedly connecting with the connecting cylinder.

[0013] Preferably, the connecting cylinder is a 3D printed structure, and a reverse-winding constant-force spring mechanism is arranged inside it and connected to the pulling cable;

[0014] An installation cable hole is provided on the connecting cylinder for connecting the pulling cable;

[0015] A bolt hole is provided on the connecting cylinder for connecting with the bolts at both ends of the multi-section electric push rod.

[0016] Preferably, the reverse-winding constant-force spring mechanism includes a constant-force spring, a passive wheel, a winding wheel, and an output wheel.

[0017] The constant-force spring is wound around the passive wheel, and one end of it is fixed on the winding wheel. The length of the constant-force spring is slightly longer than that of the pulling cable, so that the pulling cable will not reach the torsion limit of the constant-force spring during the telescopic process of the robot during scaling;

[0018] The pulling cable is wound around the output wheel;

[0019] The winding wheel and the output wheel are coaxially and fixedly connected to ensure that the pulling cable wound around the output wheel and the constant-force spring fixed on the winding wheel rotate in the same direction at the same time;

[0020] The pulling cable extends out from the cable outlet hole of the connecting cylinder and is connected to the cable hole of another connecting cylinder. Twenty-four pulling cables form eight equilateral triangles.

[0021] (III) Beneficial effects

[0022] After adopting the above technical solutions, compared with the prior art, the present invention has the following advantages:

[0023] 1. Using a constant-force spring instead of a traditional tension-compression spring can not only reduce the structural weight, but also provide more stable prestress; further, due to the existence of the constant-force spring, the pulling cable is always in a taut state during the telescopic process, ensuring the constancy of the internal force of the tension-compression member during the deformation of the robot, and greatly reducing the probability of cable relaxation and cable breakage, thereby ensuring the stability of the structure during the movement process.

[0024] 2. The telescopic movement of the multi - section electric push rod drives the torsion of the constant - force spring, and the constant - force spring drives the output wheel to rotate, realizing the telescopic movement of the pulling cable, so as to achieve the overall scaling of the robot structure, enabling the robot to freely shuttle in narrow spaces (pipe corridors, variable - cross - section water channels, etc.). The scalable robot does not need to detour when facing narrow and severe terrains. It can easily pass through by freely scaling according to the terrain structure, providing more personalized solutions for the robot path planning.

[0025] 3. The use of the reverse - winding constant - force spring mechanism enables the robot to be no longer limited by the control of too many motors. Most functions can be achieved only by controlling 6 multi - section electric push rods. While releasing space and reducing mass, it also reduces the complexity of the robot's electromechanical control. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 is the overall structural schematic diagram of the present invention;

[0027] Figure 2 is the schematic diagram of the multi - section electric push rod of the present invention;

[0028] Figure 3 is the schematic diagram of the connecting cylinder of the present invention;

[0029] Figure 4 is the cross - sectional view of the connecting cylinder of the present invention;

[0030] Figure 5 is the schematic diagram of the reverse - winding constant - force spring mechanism of the present invention.

[0031] Figure 6 is the simulation diagram of the present invention in use.

[0032] In the figure: 1. Multi - section electric push rod; 2. Pulling cable; 3. Connecting cylinder; 4. Reverse - winding constant - force spring mechanism; 5. Bolt hole; 6. Cable outlet hole; 7. Cable hole; 8. Constant - force spring; 9. Passive wheel; 10. Reel; 11. Output wheel; 12. Bolt. DETAILED DESCRIPTION OF THE INVENTION

[0033] For a clearer understanding of the technical features, objectives, and effects of the present invention, the following is described with reference to the accompanying drawings:

[0034] The specific embodiments of the present invention are described, but the protection scope of the present invention is not limited to the following.

[0035] Refer to Figures 1-5 As shown, a scalable tensegrity robot applicable to narrow terrains is characterized by including:

[0036] Six multi - joint electric push rods (1) and twenty - four pulling cables (2) that connect them to each other. The multi - joint electric push rods (1) and the pulling cables (2) together form an icosahedron spherical structure;

[0037] At both ends of each multi - joint electric push rod (1), connection cylinders (3) are provided and connected with bolts;

[0038] Each pulling cable (2) is connected to the reverse - winding constant - force spring mechanism (4) inside the connection cylinder (3), which is used to ensure that during the movement of the robot, the internal prestress of the pulling cable (2) is constant, greatly reducing the occurrence of cable relaxation and cable breakage. Due to the constant prestress, the structural stability is not easily damaged.

[0039] By remotely controlling the telescoping of the multi - joint electric push rod (1) to drive the operation of the reverse - winding constant - force spring mechanism (4), the scaling and movement functions of the tensegrity robot can be realized.

[0040] The described multi - joint electric push rod (1) is a remotely controllable type, and bolts (12) are provided at both ends for fixed connection with the connection cylinder (3). Specifically, the 6 multi - joint electric push rods (1) are all remotely controllable types. Remotely controlling the rod to extend can drive the pulling cable (2) to extend, thereby driving the constant - force spring (8) wound around the passive wheel (9) to reverse to the take - up wheel (10), and vice versa for contraction; due to the presence of the constant - force spring (8), the internal prestress of the pulling cable (2) remains constant during the scaling and rolling of the robot.

[0041] The described connection cylinder (3) is a 3D - printed structure, and a reverse - winding constant - force spring mechanism (4) is arranged inside it and connected to the pulling cable (2); specifically, the connection cylinder (3) is divided into left and right parts and is mirror - image. The 3D - printed connection cylinder (3) reserves space for installing two reverse - winding constant - force spring mechanisms (4) to fix the reverse - winding constant - force spring mechanism (4) to the connection cylinder (3).

[0042] Installation cable holes (7) are opened on the connection cylinder (3) for connecting the pulling cable (2);

[0043] Bolt holes (5) are opened on the connection cylinder (3) for connecting with the bolts (12) at both ends of the multi - joint electric push rod (1).

[0044] The reverse - winding constant - force spring mechanism (4) includes a constant - force spring (8), a passive wheel (9), a take - up wheel (10), and an output wheel (11).

[0045] The constant - force spring (8) is wound around the passive wheel (9), and one end of it is fixed to the take - up wheel (10). The length of the constant - force spring (8) is slightly longer than that of the pulling cable (2), so that during the telescoping stage of the pulling cable (2) during the scaling of the robot, the torsion limit of the constant - force spring will not be reached;

[0046] The pulling cable (2) is wound around the output wheel (11);

[0047] The retraction wheel (10) is fixedly connected coaxially with the output wheel (11) to ensure that the pulling cable (2) wound around the output wheel (11) and the constant force spring (8) fixed on the retraction wheel (10) rotate in the same direction simultaneously;

[0048] The pulling cable (2) extends out from the cable outlet hole (6) of the connecting cylinder (3) and is connected to the cable hole (7) of another connecting cylinder (3). Twenty-four pulling cables (2) form eight equilateral triangles.

[0049] Specifically, the passive wheel (9), retraction wheel (10), and output wheel (11) in the reverse-winding constant force spring mechanism (4) are all 3D printed. The retraction wheel (10) and the output wheel (11) are 3D printed as one body. Mounting holes are reserved on the retraction wheel (10) and the passive wheel (9) for installing the constant force spring (8), and mounting holes are also reserved on the output wheel (11) for installing the pulling cable (2);

[0050] The technical solution provided by the present invention:

[0051] Such as Figure 6 :

[0052] 1. Stationary:

[0053] When the robot is stationary, it is supported by the hemispherical shape at the top of the connecting cylinder. At this time, under the torsional force of the constant force spring (8), the pulling cable (2) is in a taut state, and the robot structure is in a stable state.

[0054] 2. Rolling:

[0055] One or two multi-section electric push rods (1) are remotely controlled to extend and retract, causing the center of gravity of the robot to shift, thereby realizing the rolling of the robot; when the push rod extends, the elongation of the rod member generates a pulling force on the pulling cable (2), causing the pulling cable (2) to be elongated, and the pulling force drives the constant force spring (8) to reverse and wind on the retraction wheel (10); when the push rod contracts, the torsion state of the constant force spring (8) generates a torsional force, driving the retraction wheel (10) to rotate in the reverse direction, and the output wheel (11) coaxial with it will simultaneously rewind the pulling cable (2). During this process, the uniform extension and retraction of the multi-section electric push rod (1) make the pulling force received by the pulling cable (2) and the constant force spring (8) constant. The existence of the constant force spring (8) keeps the pulling cable (2) in a taut state all the time, so the entire robot structure is always in a stable state.

[0056] 3. Shrinking:

[0057] When the robot rolls into a narrow terrain, all six multi - jointed electric push - rods (1) are controlled to shorten. Under the action of the resilience force, the constant - force spring (8) rotates, pulling the winding wheel (10) to rotate reversely, so that the constant - force spring (8) automatically returns to the passive wheel (9), and at the same time, the pulling cable (2) is wound back onto the output wheel (11), realizing the reduction of the structure. When driving in the reduced state, one or two multi - jointed electric push - rods (1) are extended and retracted to shift the center of gravity of the structure, thus achieving the purpose of rolling. If the robot is in the minimum state, only remotely controlling the extension of the multi - jointed electric push - rod (1) can also cause the center of gravity of the robot to shift to achieve the purpose of rolling. During the reduction process, similar to rolling, the internal prestress of the pulling cable (2) is in a stable state. In the minimum state, the constant - force springs have all been retracted. At this time, the internal prestress of the pulling cable (2) is related to the gravity of the structure.

[0058] 4. Enlargement:

[0059] Enlargement is the opposite of reduction. All six multi - jointed electric push - rods (1) are extended. Under the action of the thrust force, the pulling cable (2) wound on the output wheel (11) is pulled out. The output wheel (2) drives the winding wheel (10) to rotate, and the passive wheel (9) rotates reversely. In this way, the constant - force spring (8) is reversely wound on the winding wheel (10), realizing the enlargement of the structure. When driving in the enlarged state, one or two multi - jointed electric push - rods (1) are extended and retracted to shift the center of gravity of the structure, thus achieving the purpose of rolling. If the robot is in the maximum state, only remotely controlling the shortening of the multi - jointed electric push - rod (1) can also cause the center of gravity of the robot to shift to achieve the purpose of rolling. Similar to the reduction process, during the enlargement process, the internal prestress of the pulling cable (2) is in a stable state.

[0060] Whether it is the scaling - up or scaling - down process or the rolling process, the internal prestress of the tensegrity robot's pulling cable (2) of the present invention is in a constant state, and the robot structure is always in a stable state.

[0061] As described above, based on the embodiments as inspiration, through the above - described description, relevant staff can completely make various changes and modifications within the scope of not deviating from the idea of this invention. The technical scope of this utility model is not limited to the content in the specification, and its protection scope must be determined according to the scope of the claims.

Claims

1. A scalable tensegrity robot applicable to narrow terrains, characterized in that: The scalable tensegrity robot includes: Six multi-joint electric push rods (1) and twenty-four tension cables (2) connecting them to each other. The multi-joint electric push rods (1) and the tension cables (2) together form an icosahedral spherical structure; At both ends of each multi-joint electric push rod (1), there are connecting cylinders (3) which are connected by bolts; Inside the connecting cylinder (3), there is a reverse-wound constant-force spring mechanism (4). Each tension cable (2) is connected to the reverse-wound constant-force spring mechanism (4) to ensure that the internal prestress of the tension cable (2) remains constant during the scaling and rolling processes of the robot.

2. The scalable tensegrity robot applicable to narrow terrains according to claim 1, wherein: The multi-joint electric push rod (1) is remotely controllable, and bolts (12) are provided at both ends for fixedly connecting to the connecting cylinder (3).

3. The scalable tensegrity robot applicable to narrow terrains according to claim 1, wherein: The connecting cylinder (3) is a 3D printed component. On the connecting cylinder (3), there are installation cable holes (7), and the installation cable holes (7) are connected to the tension cables (2); On the connecting cylinder (3), there are bolt holes (5), and the bolt holes (5) are connected to the bolts (12) at both ends of the multi-joint electric push rod (1).

4. The scalable tensegrity robot applicable to narrow terrains according to claim 3, wherein: The reverse-wound constant-force spring mechanism (4) includes a constant-force spring (8), a passive wheel (9), a winding wheel (10), and an output wheel (11). The constant-force spring (8) is wound around the passive wheel (9), and one end of it is fixed on the winding wheel (10). The length of the constant-force spring (8) is longer than that of the tension cable (2), and the tension cable (2) is wound around the output wheel (11).

5. The scalable tensegrity robot applicable to narrow terrains according to claim 4, wherein: The winding wheel (10) and the output wheel (11) are coaxially and fixedly connected. The tension cable (2) extends out from the cable outlet hole (6) of the connecting cylinder (3) and is connected to the cable hole (7) of another connecting cylinder (3). The twenty-four tension cables (2) form eight equilateral triangles.

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