Snakelike robot based on scale propulsion mechanism and control method

Abstract

The invention discloses a snakelike robot based on a scale propelling mechanism and a control method, the snakelike robot comprises a plurality of snakelike units connected in series, each snakelike unit comprises an outer shell, a propelling joint is arranged in each outer shell, each propelling joint comprises a telescopic mechanism, the end part of the moving end of each telescopic mechanism is rotatably connected with a plurality of scales, and the scales are connected with the snakelike robot. The scales are connected with the outer wall of the outer shell through telescopic connecting rods. According to the snakelike robot, through the interconnection design of the telescopic joints and the scales, the snakelike robot is similar to water pushing motion of jellyfishes, flexible underwater motion of the snakelike robot is achieved, and the three-dimensional motion capacity, efficient propelling and accurate control can be considered.

Description

Technical Field

[0001] The present invention belongs to the technical field of snake robots, and relates to a snake robot and a control method based on the scale propulsion mechanism. Background Art

[0002] With the rapid development of fields such as underwater exploration, pipeline inspection, and marine resource development, higher requirements are put forward for the flexibility, adaptability, and motion efficiency of underwater robots. Traditional underwater robots mostly use propellers or rigid mechanical structures, which are difficult to move flexibly in complex and narrow environments, and have high energy consumption, making it difficult to meet the needs of long-term operations. Therefore, an underwater snake robot mechanism that can imitate the motion characteristics of biological snakes and has both high-efficiency propulsion and flexible maneuverability has emerged.

[0003] The existing snake robots have the following deficiencies:

[0004] 1. Traditional multi-joint snake robots can usually only achieve serpentine motion in a two-dimensional plane, lacking the ability of pitch motion, and it is difficult to flexibly adjust the posture in a complex three-dimensional environment.

[0005] 2. The propulsion efficiency of existing bionic snake robots is relatively low, making it difficult to meet the needs of long-term operations.

[0006] 3. Although flexible materials can achieve a certain degree of bionic motion, their control accuracy and structural strength are limited, and it is difficult to adapt to high-intensity underwater operation environments.

[0007] Therefore, there is an urgent need for an underwater snake robot mechanism that can balance three-dimensional motion ability, high-efficiency propulsion, and precise control. Summary of the Invention

[0008] The purpose of the present invention is to provide a snake robot and a control method based on the scale propulsion mechanism. The snake robot realizes flexible movement underwater through the telescopic joint and scale interconnection design, similar to the water-pushing motion of jellyfish, and can balance three-dimensional motion ability, high-efficiency propulsion, and precise control.

[0009] The technical solution to achieve the purpose of the present invention is as follows:

[0010] A snake robot based on the scale propulsion mechanism includes a number of serially connected snake units. Each snake unit includes an outer shell body, and a propulsion joint is arranged inside the outer shell body. The propulsion joint includes a telescopic mechanism. The end of the mobile end of the telescopic mechanism is rotatably connected with a plurality of scales, and the scales are connected to the outer wall of the outer shell body through telescopic connecting rods.

[0011] In a preferred technical solution, several serpentine units are connected by orthogonal rotary joints. The orthogonal rotary joints include two rotary joints that rotate in different directions. Front and rear card seats are arranged at both ends of the outer housing. One rotary joint in the orthogonal rotary joint is connected to the front card seat, and the other rotary joint is connected to the rear card seat.

[0012] In a preferred technical solution, a telescopic mechanism expansion frame is arranged at the mobile end of the telescopic mechanism, and the scale is rotatably connected to the end of the telescopic mechanism expansion frame.

[0013] In a preferred technical solution, the scale is an arc-shaped concave surface. The concave surface is recessed toward the side of the outer housing. A reinforcing rib with a gradually changing width is arranged in the middle of the outer side of the concave surface, and a rotating shaft is arranged in the middle of the reinforcing rib.

[0014] In a preferred technical solution, the inside of the outer housing is a hollow structure, and a waterproof structure is arranged in the middle, having a certain positive buoyancy.

[0015] The present invention also discloses a control method for a serpentine robot applied to the above-mentioned one based on the scale propulsion mechanism, including the following steps:

[0016] S01: Real-time control the motion parameters of the orthogonal rotary joints through the Serpenoid curve, and respectively control pitching and yawing;

[0017] S02: Optimize the energy consumption and propulsion efficiency by adjusting the telescopic amplitude, frequency and force of the propulsion joints of each serpentine unit.

[0018] In a preferred technical solution, in step S01, the motion of the serpentine robot is controlled by adjusting the fluctuations on different planes. A waveform is introduced in the vertical plane to make the robot generate lift or downward pressure with the fluctuations, so as to realize floating or diving. And in the horizontal plane, the yaw angle is changed by adjusting the asymmetry or phase difference of the waveform, so that the robot realizes turning.

[0019] In a preferred technical solution, the control relationship of step S01 is:

[0020]

[0021] Among them, rad[i] represents the rotation angle of the i-th joint, α is the initial angle of the rotary joint, kn is the number of S waves in the serpentine motion, s is the total arc length of the serpentine curve, L is the total length of the serpentine robot, and N is the number of serpentine units.

[0022] Compared with the prior art, the present invention has the following remarkable advantages:

[0023] 1. The snake-like robot mechanism adopts the structural design of rotating joint + propulsion joint + bionic scale-type propulsion device, which has higher propulsion efficiency and flexibility compared with traditional propeller or swinging fin propulsion methods. The double rotating joints realize pitch and yaw control, improving the adaptability of the robot in complex underwater environments; the extension and retraction of the propulsion joints drive four evenly distributed scale-like blades to pry water, reduce turbulent interference, improve propulsion stability, and its retraction distance and strength are adjustable, which can optimize energy consumption and propulsion speed. In addition, the present invention is combined with an online programming controller model, which can adjust the motion parameters in real time compared to the traditional offline programming method, so that the snake-like robot in the simulation platform can dynamically optimize the gait strategy, movement speed, retraction frequency, retraction distance and rhythm according to the terrain characteristics, thereby further improving the motion performance and environmental adaptability. The overall structure is modular, which reduces maintenance costs and is suitable for various mission scenarios such as underwater detection and environmental monitoring.

[0024] 2. By imitating the scale characteristics of biological snakes through fan blade scales, the fluid dynamics performance is optimized, the propulsion efficiency and maneuverability of the robot are significantly improved, and the problem of low propulsion efficiency of existing snake-like robots is solved. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 Schematic diagram of the structure of the snake-like robot based on the scale propulsion mechanism of this embodiment;

[0026] Figure 2 Schematic diagram of the serpentine unit structure of this embodiment;

[0027] Figure 3 is a cross-sectional view of the serpentine unit of this embodiment;

[0028] Figure 4 Schematic diagram of the orthogonal rotating joint structure of this embodiment;

[0029] Figure 5 This is a schematic diagram of the propulsion joint connection of this embodiment;

[0030] Figure 6 Schematic diagram of the scale structure of this embodiment. DETAILED DESCRIPTION

[0031] The principle of the present invention is: through the design of telescopic joints and interconnected scales, similar to the water-pushing movement of jellyfish, the snake-like robot can move flexibly underwater, and has pitch and yaw joints, which can realize the floating and diving movement of the snake-like robot in the water, further enhancing the movement ability of existing snake-like robots in water.

[0032] Embodiment 1:

[0033] like Figure 1As shown in the figure, a snake-like robot based on the scale propulsion mechanism includes several serially connected snake-like units 10. K[1-9] are the housing of each unit, P[1~9] are the telescopic joints, Fn(1, 2, 3, 4) are the scales of each unit (n = 1-9), Q(1-8) are the orthogonal selection joints. The snake-like robot body is composed of 9 identical cylindrical units, providing a total of 8 degrees of freedom, highly simulating the snake-like curve. The modular design allows the fuselage to be extended by adding units. When the robot moves underwater, the rotary joints swing according to the preset trajectory to form a snake-like motion waveform. The propulsion joints expand and contract according to the control strategy, driving the scale-like fan blades to paddle water to achieve propulsion.

[0034] As Figure 2 , 3 shown, the snake-like unit 10 includes an outer housing 11. Inside the outer housing 11, a propulsion joint 12 is provided. The propulsion joint 12 includes a telescopic mechanism. At the end of the mobile end 121 of the telescopic mechanism, a plurality of scales 13 are rotatably connected. The scales 13 are connected to the outer wall of the outer housing 11 through a telescopic link 14.

[0035] Preferably, the outer housing 11 is a cylinder. The inside of the outer housing 11 is a hollow structure, and a waterproof structure is provided in the middle, having a certain positive buoyancy.

[0036] The buoyancy of the robot is precisely adjusted. The density of each unit is lower than that of water, making it have a slight positive buoyancy to keep floating on the water surface. At the same time, the buoyancy is controlled to the minimum to ensure that all sides are submerged in water, thereby generating propulsion force. All units must be waterproof because they are in direct contact with the water body to avoid damage.

[0037] The telescopic mechanism of the propulsion joint 12 can be an electric telescopic rod, and the telescopic distance and force are adjustable to meet different propulsion requirements and improve energy utilization efficiency.

[0038] In a preferred embodiment, if as Figure 4 shown, the dry section snake-like units 10 are connected by an orthogonal rotary joint 20. The orthogonal rotary joint 20 includes two rotary joints (21, 22) that rotate in different directions. Preferably, the two rotary joints (21, 22) are distributed in the horizontal and vertical directions, and the rotary joints (21, 22) are driven by motors for selection.

[0039] At both ends of the outer housing 11, a front card seat 15 and a rear card seat 16 are provided. One rotary joint in the orthogonal rotary joint 20 is connected to the front card seat 15, and the other rotary joint is connected to the rear card seat 16.

[0040] In a preferred embodiment, a telescopic mechanism extension frame 122 is provided at the mobile end 121 of the telescopic mechanism, and the scale 13 is rotatably connected to the end of the telescopic mechanism extension frame 122. Here, the rotational connection can be a hinge connection or a connection through a rotating shaft.

[0041] A specific implementation, such as Figure 3 As shown, front end caps 17 and rear end caps 18 are provided at both ends of the outer housing 11. The front card holder 15 is provided on the front end cap 17, and the rear card holder 16 is provided on the rear end cap 18. The telescopic mechanism of the propulsion joint 12 is driven by a motor 19. The motor 19 and the telescopic mechanism are fixed to the fixing frame 123. The scale 13 is connected to the end of the telescopic mechanism expansion frame 122 through a hinge 133. The telescopic link 14 is connected to the outer wall of the outer housing 11 through a hinge 141. The front end cap 17 and the rear end cap 18 are provided with orthogonal rotary joint 20 connection parts 23.

[0042] Specifically, as Figure 5 As shown, the telescopic mechanism expansion frame 122 is similar to a cross. Four through grooves 111 are provided on the surface of the outer housing 11. The telescopic mechanism expansion frame 122 is connected to the scale 13 and reciprocates in the through grooves 111 under the telescopic action of the propulsion joint 12.

[0043] The scale 13 can be plate-shaped. Preferably, as Figure 6 As shown, the scale 13 is an arc-shaped concave surface 131. The concave surface is recessed toward the side of the outer housing 11. A reinforcing rib 132 with a gradually changing width is provided in the middle of the outer side of the concave surface. A rotating shaft is provided in the middle of the reinforcing rib 132.

[0044] Another embodiment, a control method for a snake-like robot applied to the above snake-like robot based on the scale propulsion mechanism, includes the following steps:

[0045] S01: Real-time control the motion parameters of the orthogonal rotary joint through the Serpenoid curve, and control pitching and yaw respectively;

[0046] S02: Optimize the energy consumption and propulsion efficiency by adjusting the telescopic amplitude, frequency and force of the propulsion joint of each snake unit.

[0047] In step S01, the motion of the snake-like robot is controlled by adjusting the fluctuations on different planes. A waveform is introduced in the vertical plane, so that the robot generates lift or downward pressure with the fluctuations, thereby realizing floating or diving. In the horizontal plane, the yaw angle is changed by adjusting the asymmetry or phase difference of the waveform, so that the robot realizes turning.

[0048] The control relationship of step S01 is:

[0049]

[0050] Among them, rad[i] represents the rotation angle of the i-th joint, α is the initial angle of the rotary joint, kn is the number of S waves in the snake motion, s is the total arc length of the snake curve, L is the total length of the snake-like robot, and N is the number of snake units.

[0051] Between the units are two orthogonal rotary joints, which respectively control pitch and yaw to achieve flexible movement in three-dimensional space. Propulsion joint: The telescopic stroke and force are adjustable, thereby controlling the drainage volume per unit time to optimize the propulsion effect. The telescopic movement of the propulsion joint drives the bionic scale-like propulsion device to paddle water, thus providing propulsion force. Four evenly distributed scale-like fan blades are arranged around the propulsion joint, and these fan blades paddle water with the telescopic movement of the propulsion joint to form propulsion force. It can conform to the change of water flow direction, reduce fluid resistance and improve propulsion efficiency.

[0052] An on-line programming controller is adopted, which can adjust the motion parameters of the rotary joint and the propulsion joint in real time during the movement of the robot. Combined with the CoppeliaSim simulation platform, the gait strategy is optimized in the simulation environment, and the propulsion rhythm, movement speed, telescopic frequency and gait mode are adjusted to meet the requirements of different underwater tasks.

[0053] Motion principle

[0054] The rotary joint is controlled according to the Serpenoid curve, enabling the robot to form a bionic snake-like undulating motion. The propulsion joint performs telescopic motion according to the set control strategy, driving the scale-like fan blades to paddle water to achieve propulsion. All the scales are propelled synchronously, or the scales are propelled in a streaming manner. By adjusting the telescopic amplitude, frequency and force of the propulsion joint, the energy consumption and propulsion efficiency are optimized, enabling the robot to switch between low-speed fine operation and high-speed cruising.

[0055] Key technical parameters

[0056] Rotation angle range of the rotary joint: ±30° (adjustable), telescopic stroke of the propulsion joint: 0 - 50 mm (adjustable), scale size: 10 mm - 50 mm (optimized according to hydrodynamics), control frequency: 50 Hz (supporting real-time optimization of gait strategy).

[0057] Design and modeling: Design the snake-shaped robot body in CAD software, including rotary joints, propulsion joints, scale propulsion devices, etc. After the design is completed, import the model into the CoppeliaSim simulation platform to establish a robot simulation environment.

[0058] System assembly and debugging: Assemble the rotary joint and the propulsion joint to form an alternately arranged snake-shaped robot main structure. Install the scale-like fan blades so that they are evenly distributed outside the propulsion joint, and ensure that they can paddle water when the propulsion joint expands and contracts. Debug the telescopic movement of the propulsion joint to ensure that the scale propulsion device can effectively paddle water and provide a stable propulsion force.

[0059] Simulation and Optimization: Conduct gait optimization in the CoppeliaSim simulation platform, adjust the motion parameters of the rotating joints and propulsion joints to adapt to different underwater environments. Through the online control system, adjust the propulsion mode under different task scenarios (such as cruising, fine operation, passing through narrow environments, etc.) to improve propulsion efficiency and maneuverability.

[0060] Experimental Verification: Conduct tests in an experimental pool or actual water area to verify the propulsion performance of the robot under different water flow conditions. By comparing the experimental data of different gait strategies, further optimize the motion control parameters to improve the adaptability and stability of the robot in complex environments.

[0061] The present invention realizes efficient propulsion and flexible movement through the combination of rotating joints + propulsion joints + bionic scale-type propulsion devices. Compared with traditional underwater propulsion methods (such as propeller or oscillating fin propulsion), the present invention has higher propulsion efficiency, less turbulent interference, and can adjust the motion parameters in real time through an online controller, enabling the robot to dynamically optimize the gait strategy according to environmental characteristics and improve environmental adaptability and propulsion stability.

[0062] The above embodiments are the preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the above embodiments. Any other changes, modifications, substitutions, combinations, and simplifications made without departing from the spirit and principle of the present invention shall be equivalent replacement methods and are all included in the protection scope of the present invention.

Claims

1. A snake-like robot based on the scale propulsion mechanism, comprising a number of serially connected snake-like units, characterized in that, The serpentine unit includes a housing body, and a propulsion joint is arranged inside the housing body. The propulsion joint includes a telescopic mechanism, and the end of the mobile end of the telescopic mechanism is rotatably connected with a plurality of scales. The scales are connected to the outer wall of the housing body through telescopic connecting rods.

2. The snake-shaped robot based on the scale propulsion mechanism according to claim 1, wherein Several serpentine units are connected through an orthogonal rotation joint. The orthogonal rotation joint includes two rotation joints rotating in different directions. The front clamping seat and the rear clamping seat are arranged at both ends of the housing body. One rotation joint in the orthogonal rotation joint is connected to the front clamping seat, and the other rotation joint is connected to the rear clamping seat.

3. The snake-like robot based on the scale propulsion mechanism according to claim 2, wherein A telescopic mechanism extension frame is arranged at the mobile end of the telescopic mechanism, and the scale is rotatably connected to the end of the telescopic mechanism extension frame.

4. The snake-like robot based on the scale propulsion mechanism according to claim 2, wherein The scale is an arc-shaped concave surface, and the concave surface is recessed toward the housing body side. A reinforcing rib with a gradually changing width is arranged in the middle of the outer side of the concave surface, and a rotating shaft is arranged in the middle of the reinforcing rib.

5. The snake-like robot based on the scale propulsion mechanism according to claim 1, characterized in that, The interior of the housing body is a hollow structure, and a waterproof structure is arranged in the middle, having a certain positive buoyancy.

6. A control method for a snake-shaped robot based on the scale propulsion mechanism according to any one of claims 2-4, characterized in that, It includes the following steps: S01: Real-time control the motion parameters of the orthogonal rotation joint through the Serpenoid curve to control pitch and yaw respectively; S02: Optimize the energy consumption and propulsion efficiency by adjusting the telescopic amplitude, frequency and force of the propulsion joint of each serpentine unit.

7. The control method according to claim 6, wherein In step S01, the motion of the snake robot is controlled by adjusting the fluctuations on different planes. A waveform is introduced in the vertical plane, so that the robot generates lift or downward pressure with the fluctuations, so as to realize floating or diving. And in the horizontal plane, the yaw angle is changed by adjusting the asymmetry or phase difference of the waveform, so that the robot realizes turning.

8. The control method according to claim 6, wherein The control relationship of step S01 is: Among them, rad[i] represents the rotation angle of the i-th joint, α is the initial angle of the rotation joint, kn is the number of S waves in the snake motion, s is the total arc length of the snake curve, L is the total length of the snake robot, and N is the number of serpentine units.

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