A flexible bionic arowana based on a bellows structure

Abstract

The utility model discloses a flexible bionic brocade carp based on bellows structure, including head subassembly, flexible bellows torso, tail subassembly, bionic fish tail and internal drive mechanism, the flexible bellows torso is thin -walled tubular structure, and the geometry deformation of wave crest wave trough effectively adapts the swing of fish body in the process of swimming. Compared with ordinary smooth skin structure, the bellows structure of the utility model is smaller when bending, and the rebound is more natural, so that the swimming posture of the machine fish is more flexible, realistic, and the natural swimming manner of the brocade carp can be highly restored. The utility model adopts the integrated flexible skin, has good wear resistance and anti -aging performance, can effectively avoid the problem that the traditional rigid joint structure is easy to enter sand and easy to be stuck in the water environment, and can significantly improve the service life of the bionic brocade carp.

Description

Technical Field

[0001] This utility model relates to the field of underwater robots and bionic technology, specifically to a flexible bionic koi carp based on a corrugated pipe structure. Background Technology

[0002] Existing biomimetic robotic fish mostly employ a rigid shell assembly method in their structural design. This means the head, multi-segmented torso, and tail are all independent rigid shells, connected by hinges. The disadvantages of this structure are twofold: First, to ensure joint flexibility, large gaps must be left between the shells, resulting in a discontinuous appearance, low realism, and susceptibility to getting tangled in aquatic plants or debris. Second, the waterproofing of rigid multi-jointed structures typically relies on dynamic sealing technology, which is complex, generates high frictional resistance, and is prone to leakage during prolonged underwater operation, leading to damage to internal circuitry.

[0003] Although some robotic fish currently use rubber skin, ordinary smooth rubber skin tends to wrinkle and pile up on the inside when the fish swings its body significantly, hindering movement, while the outside is prone to overstretching, leading to fatigue and breakage. Furthermore, it lacks sufficient support and can easily stick to internal parts under water pressure, affecting the normal operation of the mechanical structure.

[0004] Therefore, a biomimetic robotic fish structure is needed that can balance a highly realistic appearance, excellent flexible deformation capability, and reliable fully enclosed waterproof performance. Utility Model Content

[0005] To address the problems of stiff joints, difficulty in waterproofing and sealing, and discontinuous appearance in existing bionic robotic fish, this invention proposes a flexible bionic koi based on a corrugated pipe structure.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: a flexible bionic koi carp based on a corrugated pipe structure, the flexible bionic koi carp including a head assembly, a flexible corrugated body, a tail assembly, a bionic fish tail, and an internal drive mechanism;

[0007] The head assembly is located at the front end of the fish body, and a head connecting flange is provided at its rear end. A head connecting block is fixedly installed on one side of the head connecting flange.

[0008] The head assembly is a rigid, hard shell;

[0009] The flexible corrugated body is connected between the head assembly and the tail assembly, and its two ends are respectively sealed to the head connecting flange and the front end of the tail assembly, forming an installation cavity inside the fish body.

[0010] The tail assembly includes a caudal peduncle and a bionic fish tail;

[0011] The internal drive mechanism includes a first joint frame, a first servo mounting base, a second joint frame, a second servo mounting base, a third joint frame, and a tailstock connecting base.

[0012] Furthermore, the head assembly has a sealed chamber inside, which integrates the main control board, power module and attitude sensor.

[0013] Furthermore, the flexible corrugated body is a thin-walled tubular structure, and the outer surface of the thin-walled tubular structure is provided with several annular corrugated grooves, which are formed by several sets of flanges and grooves connected alternately.

[0014] Furthermore, the flexible corrugated body is provided with a front skin support rib and a middle skin support rib; the front skin support rib is installed between the first joint frame and the second joint frame, and the middle skin support rib is installed between the second joint frame and the third joint frame.

[0015] Furthermore, the outer diameters of the front skin support rib and the middle skin support rib are adapted to the inner diameter of the flexible corrugated body.

[0016] Furthermore, the internal drive mechanism is disposed within the mounting cavity.

[0017] Furthermore, a first servo motor is installed inside the first joint frame, which drives the second joint frame to swing through a linkage mechanism.

[0018] Furthermore, the third joint frame is connected to the tail assembly.

[0019] The beneficial effects of this invention are as follows: This invention utilizes a tubular corrugated structure to connect the fish head and tail into a single unit, eliminating the complex joint dynamic sealing of traditional robotic fish and transforming the waterproofing issue into a simple static seal at both ends, greatly improving waterproofing reliability and protecting internal components. The unique corrugated structure uses the geometric deformation of the crests and troughs to adapt to the fish's movements. Compared to ordinary smooth skin, it has less resistance when bending and a more natural rebound, making the robotic fish's swimming posture smoother and more realistic, highly replicating the swimming posture of a koi. It has high internal space utilization, modular design for easy expansion (such as adding sensors), no exposed mechanical structure, and good safety, making it very suitable as a teaching aid for science education for teenagers and underwater robots. The integrated flexible outer skin is wear-resistant and anti-aging, avoiding the problem of sand getting stuck in traditional rigid joints. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the flexible bionic koi fish of this utility model;

[0021] Figure 2 This is a schematic diagram of the internal structure of the flexible bionic koi carp of this utility model;

[0022] Figure 3 This is a schematic diagram of the flexible corrugated body of this utility model;

[0023] Figure 4 This is a schematic diagram of the flexible corrugated body of this utility model;

[0024] Figure 5 This is a schematic diagram of the flexible corrugated body structure of this utility model.

[0025] In the diagram: 1. Head assembly, 2. Flexible corrugated body, 3. Tail assembly, 4. Bionic fish tail, 5. Head connecting flange, 6. Head connecting block, 7. First joint frame, 8. First servo mount, 9. Front skin support rib, 10. Second joint frame, 11. Second servo mount, 12. Middle skin support rib, 13. Third joint frame, 14. Tailstock connecting seat. Detailed Implementation

[0026] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention.

[0027] Example

[0028] Reference Appendix Figure 1 This utility model provides a flexible biomimetic koi carp based on a corrugated pipe structure, mainly including a head assembly 1, a flexible corrugated body 2, a tail assembly 3, a biomimetic fish tail 4, and an internal drive mechanism. The head assembly 1 is located at the front end of the fish body and is a rigid shell. A head connecting flange 5 is provided at the rear end of the head assembly 1, and a head connecting block 6 is fixedly installed on one side of the head connecting flange 5. The flexible corrugated body 2 connects the head assembly 1 and the tail assembly 3. The flexible corrugated body 2 adopts an elastic tubular corrugated structure, and its two ends are respectively sealed to the head connecting flange 5 and the front end of the tail assembly 3, thereby forming a fully enclosed installation cavity inside the fish body.

[0029] Based on the above structure, the internal drive mechanism is located within the aforementioned fully enclosed mounting cavity. (See attached image) Figure 2As shown, the internal drive mechanism is mainly composed of multiple joints connected in series, including a first joint frame 7, a first servo mount 8, a second joint frame 10, a second servo mount 11, a third joint frame 13, and a tailstock connecting seat 14. Adjacent joint frames are driven by servo servos. Specifically, a first servo that controls horizontal swing is installed in the first joint frame 7, which drives the second joint frame 10 behind it to swing through a linkage mechanism. To prevent the flexible corrugated body 2 from collapsing inward due to external water pressure and interfering with mechanical movement, a front skin support rib 9 and a middle skin support rib 12 are provided at key nodes on the corrugated body 2. The outer diameter of the front skin support rib 9 and the middle skin support rib 12 is adapted to the inner diameter of the flexible corrugated body 2, serving to support the skin and maintain the streamlined appearance of the fish body; specifically, the front skin support rib 9 is installed between the first joint frame 7 and the second joint frame 10, and the middle skin support rib 12 is installed between the second joint frame 10 and the third joint frame 13.

[0030] As attached Figure 3 To be continued Figure 5 As shown, the structural features of the flexible corrugated body 2 are highlighted. The flexible corrugated body 2 is a thin-walled tubular structure integrally injection molded, preferably made of 35A soft rubber. The outer surface of the thin-walled tubular structure has several annular corrugated grooves, and its wall undulates periodically along the axial direction, consisting of several sets of alternating flanges and grooves. The flanges protrude outwards, providing radial support stiffness and maintaining the full appearance of the fish body; the grooves are recessed inwards, forming stress release zones during deformation. When the internal drive mechanism causes the fish body to bend, the grooves on the inner side of the bend are compressed and contract, narrowing the corrugation spacing, while the grooves on the outer side of the bend are stretched and expand, widening the corrugation spacing. This ensures that the surface of the flexible corrugated body 2 does not produce irregular wrinkles or stacking when it swings significantly, greatly reducing the elastic resistance of the material itself and improving energy utilization.

[0031] As attached Figure 1 and attached Figure 2 As shown, to address the difficulty of waterproofing multi-joint structures in existing technologies, this embodiment abandons the traditional axial dynamic seal and replaces it with a static seal structure. The head and tail ends of the flexible corrugated body 2 are secured to the head connecting flange 5 and the tail connecting frame for waterproofing. The head assembly 1 has an independent sealed chamber inside, which integrates the main control board, power module, and attitude sensor. To further ensure waterproof reliability, the tail assembly 3 and the bionic fish tail 4 are designed to be connected to the sealed exterior of the flexible corrugated body 2. This external connection method avoids the drive shaft directly penetrating the flexible skin, thus ensuring that the fish tail does not compromise the overall seal integrity during violent swinging.

[0032] As attached Figure 2As shown, the power unit employs a multi-stage servo motor series drive. The servo motor in the first joint frame 7 controls the swaying amplitude of the front section of the fish's body, the servo motor in the second joint frame 10 controls the swaying amplitude of the middle section of the fish's body, and the third joint frame 13 connects to the tail assembly 3. The third joint frame 13 is located at the very end of the internal drive mechanism, serving as the power output interface, and its rear end has a reserved mounting position for fixing the tail assembly 3. The tail assembly 3 includes a rigid tailstock and a flexible bionic fish tail 4. During swimming, the bionic fish tail 4 sways with the tailstock, striking the water flow to generate propulsion. By adjusting the phase difference and swaying amplitude of each servo motor, various swimming postures of the koi, such as C-shaped start and S-shaped cruising, can be simulated.

[0033] It can be used as an educational robot. The front end of the head component 1 has a reserved expansion interface, which can be equipped with an underwater camera or a water quality detection sensor. When used as a teaching tool, students can modify the gait algorithm in the main control board by programming, change the swing frequency of each joint servo motor, observe the wave deformation and swimming efficiency of the flexible wave-shaped body 2 at different frequencies, and thus intuitively understand the kinematics principle of wave bodies.

[0034] The working principle of this invention is as follows: After the user turns on the power switch, the control system inside the head assembly 1 issues a command. The various servo motors in the internal drive mechanism start working according to the preset CPG (Central Pattern Generator) algorithm.

[0035] Drive transmission: The rotation of the servo motor drives the first joint frame 7, the second joint frame 10 and the tailstock connecting seat 14 to rotate relative to each other.

[0036] Flexible Deformation: As the internal skeleton swings left and right, the flexible corrugated torso 2 wrapped on the outside undergoes elastic deformation. Due to the characteristics of the corrugated structure, the corrugations on the inside of the torso contract when bending, while the corrugations on the outside stretch, greatly reducing the resistance of the skin to the internal mechanism. At the same time, the elastic force of the skin assists in joint reset, reducing energy consumption.

[0037] Posture adjustment: The front skin support rib 9 and the middle skin support rib 12 always support the flexible outer skin to ensure the fish body is plump.

[0038] Swimming is achieved by transmitting this continuous wave-like oscillation to the tail component 3, where the splashing water generates a reaction force that propels the biomimetic koi forward. Throughout the process, the fully enclosed corrugated skin structure prevents external water from entering the fish's body, ensuring the absolute safety of the internal circuitry and mechanical structure.

[0039] The above description is merely a preferred embodiment of the present utility model and is not intended to limit the present utility model in any way. Therefore, any modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of the present utility model without departing from the technical solution of the present utility model shall still fall within the scope of the technical solution of the present utility model.

Claims

1. A flexible biomimetic koi carp based on a corrugated pipe structure, characterized in that, The flexible bionic koi includes a head assembly (1), a flexible corrugated body (2), a tail assembly (3), a bionic fish tail (4), and an internal drive mechanism; The head assembly (1) is located at the front end of the fish body, and a head connecting flange (5) is provided at its rear end. A head connecting block (6) is fixedly installed on one side of the head connecting flange (5). The head assembly (1) is a rigid hard shell; The flexible corrugated body (2) is connected between the head assembly (1) and the tail assembly (3), and its two ends are respectively sealed to the head connecting flange (5) and the front end of the tail assembly (3), forming an installation cavity inside the fish body; The tail component (3) includes a caudal peduncle and a bionic fish tail (4). The internal drive mechanism includes a first joint frame (7), a first servo mount (8), a second joint frame (10), a second servo mount (11), a third joint frame (13), and a tailstock connector (14).

2. The flexible biomimetic koi carp based on a corrugated pipe structure according to claim 1, characterized in that, The head assembly (1) has a sealed chamber inside, which integrates a main control board, a power module and an attitude sensor.

3. The flexible biomimetic koi carp based on a corrugated pipe structure according to claim 1, characterized in that, The flexible corrugated body (2) is a thin-walled tubular structure. The outer surface of the thin-walled tubular structure is provided with several annular corrugated grooves. The annular corrugated grooves are formed by several sets of flanges and grooves connected alternately.

4. The flexible biomimetic koi carp based on a corrugated pipe structure according to claim 1, characterized in that, The flexible corrugated body (2) is provided with a front skin support rib (9) and a middle skin support rib (12); the front skin support rib (9) is installed between the first joint frame (7) and the second joint frame (10), and the middle skin support rib (12) is installed between the second joint frame (10) and the third joint frame (13).

5. A flexible biomimetic koi carp based on a corrugated pipe structure according to claim 4, characterized in that, The outer diameters of the front skin support rib (9) and the middle skin support rib (12) are adapted to the inner diameter of the flexible corrugated body (2).

6. The flexible biomimetic koi carp based on a corrugated pipe structure according to claim 1, characterized in that, The internal drive mechanism is located within the mounting cavity.

7. A flexible biomimetic koi carp based on a corrugated pipe structure according to claim 1, characterized in that, The first joint frame (7) is equipped with a first servo motor, which drives the second joint frame (10) to swing through the linkage mechanism.

8. A flexible biomimetic koi carp based on a corrugated pipe structure according to claim 1, characterized in that, The third joint frame (13) is connected to the tail assembly (3).

Images