Underwater robotic fish based on soft beam high-order vibration driving

Abstract

The invention discloses an underwater robotic fish based on soft beam high-order vibration driving, and belongs to the technical field of underwater bionic robotic fish, the underwater robotic fish comprises a casing, a steering engine, a steering engine push rod and a soft coupling fishtail assembly; the steering engine is arranged in the shell; the output end of the steering engine is connected to a steering engine push rod, and the steering engine push rod is connected to the flexible coupling fishtail assembly; the steering engine drives the steering engine push rod to apply excitation to the flexible coupling fishtail assembly so that the flexible coupling fishtail assembly can generate vibration, and therefore the underwater robotic fish can advance and steer. The fishtail is designed and manufactured by using a soft material, the flexible beam is excited by using the steering engine, so that the flexible beam and the soft rubber tail fin generate vibration, the robot fish is pushed to advance by the reactive force of a water body to the fishtail in the vibration process, and the flexible fishtail moves more stably, more quickly and more closely to the movement of a real fish compared with a rigid fishtail; and the robot is small in occupied volume, can pass through a narrow water area, is better in movement effect, and can be used for underwater rescue and underwater narrow space exploration.

Description

Technical Field

[0001] The present invention belongs to the technical field of underwater bionic robotic fish, and more specifically, relates to an underwater robotic fish driven by high-order vibration of a soft beam. Background Art

[0002] Underwater robotic fish have always been a particularly fascinating topic in scientific research. Over the past few decades, with the advancement of science, researchers have designed a wide variety of underwater robotic fish, and their performance has continuously improved. Existing research shows that underwater robotic fish have biomimetic appearances, can approach schools of fish for photography, are quiet and energy-efficient, and, compared to currently available underwater robots, can easily navigate narrow passages and exhibit strong environmental adaptability. Therefore, underwater robotic fish have become a hot topic in scientific research, and numerous underwater robotic fish have been designed and manufactured.

[0003] Among published or authorized patents, most of the disclosed technical solutions for underwater robotic fish designs utilize rigid structures for their tails. However, rigid structures have limitations in terms of actuation (low-order modes and inflexible motion). The introduction of flexible materials can effectively address these challenges. Furthermore, if the entire tail of a robotic fish is made of flexible materials, it is prone to noise instability and lacks propulsion. Therefore, it is urgent to design an underwater bionic robotic fish that fully utilizes the advantages of flexible materials, such as high motion efficiency and strong pressure-bearing capacity, while also utilizing rigid materials to maintain the stability of the tail. Summary of the Invention

[0004] In response to the above defects or improvement needs of the existing technology, the present invention provides an underwater robotic fish based on high-order vibration drive of a soft beam, thereby solving the technical problems of the existing underwater robot's rigid structure, which is inflexible in movement, low swimming efficiency, and difficulty in integrating into fish schools.

[0005] To achieve the above-mentioned objectives, according to one aspect of the present invention, an underwater robotic fish based on soft beam high-order vibration drive is provided, comprising a housing, a servo, a servo push rod and a soft-coupled fishtail assembly; the servo is arranged inside the housing; the output end of the servo is connected to the servo push rod, and the servo push rod is connected to the soft-coupled fishtail assembly; the servo drives the servo push rod to excite the soft-coupled fishtail assembly to cause the soft-coupled fishtail assembly to vibrate, thereby enabling the underwater robotic fish to move forward and turn.

[0006] Preferably, the soft coupling fishtail assembly includes a flexible beam and a soft beam, and the soft beam is connected to one end of the flexible beam.

[0007] Preferably, the flexible beam is an elastic beam body, and the soft beam is a soft plastic beam body; the elastic beam body and the soft plastic beam body are adhesively connected.

[0008] Preferably, the connection between the elastic beam body and the soft rubber beam body is sealed with waterproof glue.

[0009] Preferably, the housing includes an outer shell and a back cover, and the back cover is mounted on the outer shell to form a sealed chamber in the housing.

[0010] Preferably, the shell is a manta ray imitation shell, and the manta ray imitation shell is made by 3D printing.

[0011] Preferably, it also includes a main control board and a communication module, which are respectively arranged in the casing; the communication module is used to receive an external command signal and transmit the command signal to the main control board; the main control board is used to control the servo to drive the servo push rod to excite the soft coupling fishtail assembly and make the soft coupling fishtail assembly vibrate after receiving the command signal.

[0012] Preferably, the length of the underwater robotic fish is 130 mm.

[0013] In general, the above technical solutions conceived by the present invention can achieve the following beneficial effects compared with the prior art:

[0014] 1. The underwater robotic fish based on soft beam high-order vibration drive proposed in the present invention is provided with a soft coupling fish tail assembly, and the servo drives the servo push rod to apply excitation to the soft coupling fish tail assembly, thereby generating vibration of the soft coupling fish tail assembly, and then utilizes the reaction force of the water body on the fish tail during the vibration to drive the robotic fish to complete various movements.

[0015] 2. The underwater robotic fish proposed in the present invention is driven by high-order vibrations of a soft beam, in which the soft-coupled fishtail assembly is composed of a flexible beam and a soft beam, which can enable the robotic fish to pass through narrow waters while encountering little water resistance, ensuring that the robotic fish can move quickly.

[0016] 3. The underwater robotic fish proposed in the present invention, which is driven by high-order vibration of a soft beam, has a fish body structure that has been optimized through simulation design and manufactured through 3D printing. While ensuring operation, it is subject to minimal water resistance. It is simple to assemble, easy to implement, low in cost, and convenient for mass production.

[0017] 4. The underwater robotic fish proposed in this invention, which is driven by high-order vibration of a soft beam, is 130 mm long. Experiments show that its movement speed is 152 mm / s, or 1.17 BL / s, and it can move normally in a flow field with a head-on flow velocity of less than 150 mm / s. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 This is a schematic diagram of the structure of the underwater robotic fish driven by high-order vibration of a soft beam according to the present invention;

[0019] Figure 2 This is a side view of the structure of the underwater robotic fish driven by high-order vibration of a soft beam according to the present invention;

[0020] Figure 3 This is a speed comparison diagram of the underwater robotic fish driven by the soft beam high-order vibration at different frequencies.

[0021] In all the drawings, the same reference numerals are used to denote the same elements or structures, wherein: 1 - housing; 2 - switch; 3 - back cover; 4 - servo; 5 - servo push rod; 6 - soft beam; 7 - flexible beam. DETAILED DESCRIPTION

[0022] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely for the purpose of explaining the present invention and are not intended to limit the present invention. In addition, the technical features involved in the various embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other.

[0023] like Figure 1-3 As shown, the present invention proposes an underwater robotic fish based on soft beam high-order vibration drive, which includes a shell 1, a switch 2, a back cover 3, a servo 4, a servo push rod 5, a main control board, a communication module, a battery and a soft coupling fishtail assembly.

[0024] Specifically, the back cover 3 is installed at the rear of the housing 1 to form a casing with a sealed chamber.

[0025] In a preferred embodiment of the present invention, the shell 1 is a manta ray-like shell, which is designed using simulation software and manufactured using 3D printing.

[0026] To further illustrate, the main control board, communication module, and battery are located within the housing, while the switch is located outside the housing. The communication module establishes a transmission channel with external signals, transmitting information to the main control board for control. The main control board, powered by the battery, functions as a signal transmitter and receiver, and the output signals control the movement of the servo 4.

[0027] To further explain, the soft coupled fishtail assembly of the present invention includes a flexible beam 7 and a soft beam 6 connected end to end.

[0028] As a preferred embodiment of the present invention, the flexible beam 7 is an elastic beam body, and the soft beam 6 is a soft plastic beam body. The elastic beam body and the soft plastic beam body are bonded together, and the connection between the two is sealed with waterproof glue.

[0029] The present invention provides an underwater robotic fish driven by high-order vibration of a soft beam. First, the robot's appearance and movement mode are bionic. The robotic fish is modeled after a manta ray in appearance, realistically restoring the manta ray's head, body, pectoral fin and tail fin structure. In addition, the robotic fish is compact and can be integrated into a school of fish for close observation. Then, a main control board is used to control the tail servo to swing according to the fish body wave equation, driving the entire robot to move forward or turn. The present invention differs from other robotic fish in its driving method. It uses a method of applying excitation to the high-order soft beam to make it vibrate, and then uses the amplitude of its vibration to drive the robotic fish to complete various movements.

[0030] To further illustrate, the working process of the underwater robotic fish of the present invention includes the following four stages:

[0031] In stage 1, the main control board receives computer instructions and controls the tail servo to rotate according to the fish body wave equation, thereby driving the robot fish to move forward as a whole;

[0032] In stage 2, when moving forward, the computer sends a signal to the tail servo to apply a force frequency that matches the second-order natural frequency of the flexible beam, causing the tail to produce second-order resonance and the robot fish to reach maximum speed.

[0033] In stage 3, when turning is required and an obstacle is encountered, the operator can send instructions to the main control board through the computer to control the tail servo to make the robot fish turn left or right.

[0034] It will be easily understood by those skilled in the art that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. An underwater robotic fish based on high-order vibration drive of a soft beam, characterized in that: The invention comprises a housing, a steering gear (4), a steering gear push rod (5) and a soft coupling fishtail assembly; the steering gear (4) is arranged inside the housing; the output end of the steering gear (4) is connected to the steering gear push rod (5), and the steering gear push rod (5) is connected to the soft coupling fishtail assembly; the steering gear (4) drives the steering gear push rod (5) to apply excitation to the soft coupling fishtail assembly so that the soft coupling fishtail assembly generates vibration, thereby enabling the underwater robot fish to move forward and turn.

2. The underwater robotic fish based on soft beam high-order vibration drive according to claim 1, characterized in that: The soft coupling fishtail assembly comprises a flexible beam (7) and a soft beam (6), wherein the soft beam (6) is connected to one end of the flexible beam (7).

3. The underwater robotic fish based on soft beam high-order vibration drive according to claim 2, characterized in that: The flexible beam (7) is an elastic beam body, and the soft beam (6) is a soft rubber beam body; the elastic beam body is bonded to the soft rubber beam body.

4. The underwater robotic fish based on soft beam high-order vibration drive according to claim 3, characterized in that: The connection between the elastic beam body and the soft rubber beam body is sealed with waterproof glue.

5. The underwater machine based on soft beam high-order vibration drive according to claim 1, characterized in that: The housing comprises an outer shell (1) and a back cover (3); the back cover (3) is mounted on the outer shell (1) so as to form a closed chamber in the housing.

6. The underwater robotic fish based on soft beam high-order vibration drive according to claim 5, characterized in that: The shell (1) is a manta ray imitation shell, and the manta ray imitation shell is manufactured by 3D printing.

7. The underwater robotic fish based on soft beam high-order vibration drive according to claim 1, characterized in that: It also includes a main control board and a communication module, which are respectively arranged in the housing; the communication module is used to receive an external command signal and transmit the command signal to the main control board; the main control board is used to control the steering gear (4) to drive the steering gear push rod (5) to apply excitation to the soft coupling fishtail component and cause the soft coupling fishtail component to vibrate after receiving the command signal.

8. The underwater robotic fish based on soft beam high-order vibration drive according to claim 1, characterized in that: The length of the underwater robotic fish is 130 mm.

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