Multi-joint bionic eel structure composed of polyvinyl chloride gel drivers

Abstract

The invention belongs to the technical field of bionic robots, and particularly relates to a multi-joint bionic eel structure composed of polyvinyl chloride gel drivers. Comprising a fish body, a fish head and a fish tail, the fish body comprises a framework, the framework is composed of a plurality of single-joint frameworks, each single-joint framework comprises an oval main body structure, the oval main body structures are arranged in parallel, and rotating holes in every two adjacent pairs of bosses are hinged through a rotating shaft; and a PVC gel driver is arranged in the middle of the main body structure. The multi-joint bionic eel structure provided by the invention is wider in application range; the single-joint framework is elliptical and can be closer to the skin, so that the water pressure received by the fish body is uniformly shared by the framework; a transmission system is simple, the controllability is good, the manufacturing cost is low, and the feasibility is high; the structure of the bionic robotic fish is simplified, the stability is good, the noise generated in the operation process of the robotic fish is reduced, and the movement concealment of the robotic fish is improved; and the manufacturing cost is effectively saved.

Description

Technical Field

[0001] The present invention belongs to the technical field of bionic robots, and particularly relates to a multi-joint bionic eel structure composed of polyvinyl chloride gel actuators. Background Art

[0002] The ocean is a strategic area for the development of the country in the new era. It plays a crucial role in promoting the country's economic development, deepening the pattern of opening up to the outside world, and safeguarding national sovereignty. The exploration, protection, and utilization of marine resources have always been one of the key areas of national concern. However, due to factors such as the complex working environment and harsh working conditions in the ocean, the existing marine robots generally have the defects of unclear motion design and poor environmental adaptability. Therefore, designing a bionic robot that can operate in a complex marine environment is of great significance for the development and protection of China's marine resources.

[0003] In the design process of underwater robotic fish in the past, motor drive has often been the main drive mode of robotic fish. Its advantage is that it can provide strong driving force. However, rigid motors are often difficult to fully control the degrees of freedom of robotic fish, resulting in discontinuous motion during the operation of robotic fish and making it difficult to truly simulate the motion of fish. At the same time, the noise generated during the operation of the motors of such robots is also one of the inevitable defects of such robots. In recent years, the development of materials and drive technologies has promoted the research of soft robotic fish. Different from the traditional motor drive mode, flexible material drive can simplify the transmission system, improve the coherence, stability, and concealment of the motion of robotic fish, providing a feasible reference route for further optimizing the performance of underwater robotic fish. The document "202010531496.0" discloses "a bionic fish tail structure driven by PVC gel artificial muscles", including a multi-joint bionic fish tail skeleton, multiple PVC gel artificial muscle drive modules, as well as a caudal fin, a tail end, and a skin and other accessories. The bionic fish tail skeleton is composed of a pre-pressing block, a joint shaft, and an installation groove; the drive module of the PVC gel artificial muscle is composed of multiple PVC gel drive units, where an anode, a PVC gel membrane, and a cathode form a PVC gel drive unit; two PVC gel drive modules and a section of the bionic fish tail skeleton form a drive joint; by alternately driving left and right to bend and deform, swinging is generated. Its disadvantages are: due to the T-shaped bionic fish tail skeleton, the fitting with the skin is not tight, and complex bending motion cannot be achieved; at the same time, the fulcrum of the T-shaped skeleton is linear, and the swinging amplitude is difficult to control, so the probability of failure in the action increases, and the failure rate is high. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a multi-joint bionic eel structure composed of polyvinyl chloride gel actuators in view of the deficiencies of the above-mentioned prior art, which cannot achieve complex bending motion and has a high failure rate.

[0005] To achieve the above object, the present invention adopts the following technical solutions: A multi-joint bionic eel structure composed of polyvinyl chloride gel actuators, including a fish body, a fish head and a fish tail, characterized in that: the fish body contains a skeleton and is wrapped with a skin outside; the fish head is fixedly connected to the first joint of the skeleton, and the fish tail is fixedly connected to the last joint of the skeleton; the skeleton is composed of multiple single-joint skeletons, and each single-joint skeleton includes an elliptical main structure, and a pair of bosses provided with rotation holes are respectively arranged at the ends of the long axis direction of the elliptical ring surface, and a pair of bosses on the same side of the elliptical ring surface are symmetrically arranged with respect to the elliptical center; the elliptical main structures of multiple single-joint skeletons are all arranged in parallel, and the rotation holes on adjacent pairs of bosses are hinged through a rotating shaft; a PVC gel actuator is arranged in the middle of the main structure.

[0006] Further, the above PVC gel actuator is composed of a driver bottom plate, a PVC gel drive module and a driver upper plate; the driver bottom plate is fitted and fixed in the main structure, and a pair of semi-elliptical PVC gel drive modules arranged symmetrically along the long axis of the main structure are adhesively fixed between the driver bottom plate and the driver upper plate; several convex columns are fixedly arranged on the driver bottom plate, which are respectively fixedly connected to the PVC gel drive module and the driver upper plate, and at the same time, there is a gap between the end part and the driver bottom plate of the adjacent next skeleton.

[0007] Further, the upper part of the above driver upper plate is provided with a convex strip; the convex strip is in close contact with the driver bottom plate on the adjacent single-joint skeleton and can be movably matched.

[0008] Further, the outer side of the above driver bottom plate is provided with a lead wire groove and an installation groove for fixing an integrated circuit board.

[0009] Compared with the prior art, the present invention has the following beneficial effects:

[0010] 1. The multi-joint bionic eel structure provided by the present invention designs a flat fish head, and the connection curve between the fish head and the body is consistent, and the structure is more bionic and can be well integrated with the surrounding environment, and the application range is wider; at the same time, the inside of the fish head is hollow, which can give the setting space for the total control and the counterweight block, and will not cause any influence on the movement of the body part. The single-joint skeleton is elliptical, which can be closer to the skin, so that the water pressure received by the fish body is evenly shared by the skeleton.

[0011] 2. The PVC gel actuator provided by the present invention is symmetrically semi-elliptical, which can make the force transmission more uniform. By controlling the contraction and restoration of the PVC gel drive modules symmetrically distributed on both sides of the bionic eel skeleton joints, the bionic eel movement is completed. The transmission system is simple, with good controllability, low production cost, and high feasibility. Each joint is separately provided with a drive integrated circuit board, which can separately achieve the contraction control of the PVC gel actuator module of the joint and complete different movement modes of the eel. Each gel drive module is stacked by multiple deformable PVC gel drive units. By directly controlling the PVC gel actuator, the bionic eel movement can be realized, and flexible deformation can be achieved. The bionic eel movement has good coherence. Based on a reasonable structure, through multi-channel cooperation, the movement of each joint of the eel can be driven and controlled, and the switching of different movement modes of the eel can be realized. The driving method is simple and the controllability is strong. By controlling the voltage applied to the PVC gel actuator, the joint can be freely rotated between 0° and 5°, with good flexibility. By orderly controlling the rotation angles of all joints, the "S"-shaped movement or other bionic movement modes of the bionic eel are completed.

[0012] 3. The present invention simplifies the structure of the bionic robotic fish, has good stability, reduces the noise generated during the operation of the robotic fish, and improves the concealment of the robotic fish movement. The components of the fish body other than the PVC gel drive module and the skin can be processed by various methods such as 3D printing, metal processing, and silicone, not limited to one method, effectively saving the production cost. Description of the Drawings

[0013] Figure 1 It is a schematic diagram of the whole bionic eel;

[0014] Figure 2 It is a schematic diagram of a single-joint skeleton with a PVC gel actuator;

[0015] Figure 3 It is a schematic diagram of the single-joint skeleton structure;

[0016] Figure 4 It is a schematic diagram of the actuator bottom plate;

[0017] Figure 5 It is a schematic diagram of the integrated circuit board;

[0018] Figure 6 It is a schematic diagram of the fish head;

[0019] Figure 7 It is a schematic diagram of the fish tail;

[0020] Figure 8 It is an effect diagram of the bionic eel movement.

[0021] Wherein: 1. fish tail; 2. skeleton; 3. PVC gel driver; 4. fish head; 5. skin; 6. boss; 7. through hole; 8. oval main body structure; 9. driver bottom plate; 10. PVC gel drive module; 11. driver upper plate; 12. convex column; 13. convex strip; 14. installation groove; 15. lead groove. Detailed implementation mode

[0022] The technical solution of the present invention will be further described in detail below with reference to the drawings and embodiments.

[0023] Refer to Figure 1 , the present invention provides a multi-joint bionic eel structure composed of polyvinyl chloride gel drivers, including a fish body, a fish head 4 and a fish tail 1. The fish body contains a skeleton 2 and is wrapped with a skin 5 on the outside. The fish head 4 is fixedly connected to the first joint of the skeleton 2, and the fish tail 1 is fixedly connected to the last joint of the skeleton 2.

[0024] See Figure 2 , the skeleton 2 is composed of multiple single-joint skeletons. Each single-joint skeleton includes an oval main body structure 8. At the end parts in the long axis direction of the oval ring surface, a pair of bosses 6 provided with through holes 7 are respectively arranged. Four bosses 6 are arranged on each main body structure 8. A pair of bosses 6 on the same side of the oval ring surface are symmetrically arranged with respect to the center of the oval. The two bosses 6 at the upper and lower ends of the two main body structures 8 can be fitted and stacked.

[0025] The oval main body structures 8 of multiple single-joint skeletons are all arranged in parallel, and the through holes 7 on the adjacent pairs of bosses 6 are hinged through a rotating shaft.

[0026] See Figure 3 and Figure 4 , a PVC gel driver 3 is arranged in the middle of the main body structure 8. The PVC gel driver 3 is composed of a driver bottom plate 9, a PVC gel drive module 10 and a driver upper plate 11. The driver bottom plate 9 is fitted and fixed in the main body structure 8. A pair of semi-elliptical PVC gel drive modules 10 arranged symmetrically along the long axis of the main body structure 8 are adhesively fixed between the driver bottom plate 9 and the driver upper plate 11. Several convex columns 12 are fixedly arranged on the driver bottom plate 9 and are respectively fixedly connected to the PVC gel drive module 10 and the driver upper plate 11, which are used to limit the PVC drive module 10 and the driver upper plate 11. At the same time, there is a gap between the end part thereof and the driver bottom plate 9 of the adjacent next skeleton, without redundancy.

[0027] On the upper part of the upper board 11 of the driver, there are ribs 13 for concentrating force transmission, and the length direction thereof is consistent with the long axis direction of the main body structure 8. In this embodiment, four ribs 13 are provided to further ensure the stability of its swing. The rib 13 is in close contact and movable cooperation with the driver bottom plate 9 on the adjacent single-joint skeleton for force transmission to the next skeleton, and the cylindrical shape adapts to the left and right deflection of the skeleton.

[0028] Refer to Figure 4 , on the outer side of the driver bottom plate 9, there are lead grooves 15 and mounting grooves 14 for fixing the integrated circuit board.

[0029] Refer to Figure 5 , the integrated circuit board is used to control the actions of each section. It adopts a conventional design, including a point source, a main control circuit, and a boost circuit that are connected in sequence in a conventional manner. There are also signal outputs and high-voltage acquisitions on the main control circuit respectively, and there are discharge circuits and high-voltage outputs on the boost circuit respectively. Data transmission between it and the PVC gel drive module 10 and the total control board is realized through five data lines, and the total control board independently controls the integrated circuit boards of each joint.

[0030] The PVC gel drive module 10 is stacked by a plurality of PVC gel drive units. The PVC gel drive unit is stacked by a cathode, a PVC gel film, and an anode. All the cathodes in the same PVC gel drive module 10 are connected in parallel to the negative pole of the power supply, and all the anodes are connected in parallel to the positive pole of the power supply.

[0031] When a voltage is applied, the DBA molecules in the PVC gel film move against the electric field lines under the stimulation of the electric field and move towards the anode, and each PVC gel drive unit shrinks, thereby generating a contraction of the PVC gel drive module 10 in the thickness direction; after the voltage is removed, the PVC gel drive module 10 returns to its original state.

[0032] The installation process of the single-joint skeleton is as follows: Stack a plurality of PVC gel drive units into the PVC gel drive module 10, glue a pair of PVC gel drive modules 10 to the driver bottom plate 9, and glue the upper board 11 of the driver to the other side of the PVC gel drive module 10, and at the same time, assist in fixing through the ribs 13 located on the driver bottom plate 9. Install the PVC gel driver 3 on the main body structure 8. A plurality of single-joint skeletons are arranged in parallel. After adjacent joints are fixed with a certain pre-tightening force, the rotating holes of adjacent two single-joint skeletons are hinged through a rotating shaft. The integrated circuit board is fixed in the mounting groove 14, and the leads are led out from the side and ventral side of the bionic eel ridge through the lead grooves 15.

[0033] Refer to Figure 6 , the fish head 4 is flat, set in the shape of a fish head, and is connected to the fish body through a connecting piece. The fish tail 1 is also connected to the fish body through a connecting piece. Refer to Figure 7, a flaky caudal fin is provided on the fish tail 1. The connecting member can be an elliptical sheet or an arc-shaped connecting sheet, and any structure that can achieve connection can be adopted.

[0034] There is a cavity in the fish head 4 for placing the power supply and the main control board. The fish tail 1 is triangular, and the tail length is 15% of the total length of the bionic eel. The number of joints of the bionic eel is 15 - 25.

[0035] When the bionic eel is working, the PVC gel drive module 10 on one side is loaded with voltage and shrinks and shortens, and the PVC gel drive module 10 on the other side is unloaded with voltage and restores its deformation and elongates. The thrust generated by the PVC gel drive module 10 during the elongation process is used to drive the deformation of the fish body.

[0036] The installation process of the bionic eel fish body is as follows: The fish head 4 is fixedly connected to the first joint of the skeleton 2, and the fish tail 1 is fixedly connected to the last joint of the skeleton 2. The power supply and the main control board of the bionic eel are placed in the cavity of the fish head 4, and the leads of the PVC gel driver 3 are led out along the dorsal and ventral sides of the bionic eel and connected to the main control board.

[0037] The main control board of the bionic eel controls the integrated circuit boards installed on each joint of the eel fish body, and then controls the PVC gel driver 3. The thrust generated after the PVC gel drive module 10 is unloaded with voltage is used to drive the deformation of the fish body.

[0038] Please refer to Figure 8 , by controlling the loading and unloading conditions of the PVC gel drive module 10, the joint posture of the bionic eel can be changed to achieve the "S"-shaped movement of the eel.

[0039] The above content is only to illustrate the technical idea of the present invention, and the protection scope of the present invention cannot be limited thereby. Any modification made on the basis of the technical solution according to the technical idea proposed by the present invention falls within the protection scope of the claims of the present invention.

Claims

1. A multi-jointed bionic eel structure composed of polyvinyl chloride gel actuators, comprising a fish body, a fish head (4) and a fish tail (1), characterized in that: The fish body includes a skeleton (2) and is wrapped with a skin (5) on the outside; the fish head (4) is fixedly connected to the first joint of the skeleton (2), and the fish tail (1) is fixedly connected to the last joint of the skeleton (2); the skeleton (2) is composed of a plurality of single-joint skeletons, each of which includes an elliptical main structure (8), and a pair of bosses (6) provided with rotating holes (7) are respectively provided at the ends of the elliptical ring surface in the long axis direction, and the pair of bosses (6) on the same side of the elliptical ring surface are respectively symmetrically arranged with respect to the center of the ellipse; the elliptical main structures (8) of the plurality of single-joint skeletons are all arranged in parallel, and the rotating holes (7) on two adjacent pairs of bosses (6) are hinged through a rotating shaft; and a PVC gel driver (3) is arranged in the middle of the main structure (8).

2. The multi-jointed bionic eel structure composed of polyvinyl chloride gel actuators according to claim 1, characterized in that: The PVC gel driver (3) is composed of a driver base plate (9), a PVC gel driver module (10), and a driver upper plate (11); the driver base plate (9) is embedded and fixed in the main structure (8); a pair of semi-elliptical PVC gel driver modules (10) symmetrically arranged along the long axis of the main structure (8) are adhesively fixed between the driver base plate (9) and the driver upper plate (11); a plurality of convex columns (12) are fixedly arranged on the driver base plate (9), which are respectively fixedly connected to the PVC gel driver module (10) and the driver upper plate (11), and a gap is left between the end of the convex column and the driver base plate (9) of the next adjacent frame.

3. The multi-jointed bionic eel structure composed of polyvinyl chloride gel actuators according to claim 2, characterized in that: A convex strip (13) is provided on the upper part of the driver upper plate (11); the convex strip (13) is in close contact and can be movably matched with the driver bottom plate (9) on the adjacent single-joint frame.

4. The multi-jointed bionic eel structure composed of polyvinyl chloride gel actuators according to claim 3, characterized in that: The outer side of the driver bottom plate (9) is provided with a lead groove (15) and a mounting groove (14) for fixing an integrated circuit board.

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