Line-driven bionic flexible robotic fish and use method thereof

Abstract

The invention discloses a line-driven bionic flexible robotic fish and a using method thereof. The line-driven bionic flexible robotic fish comprises a rigid fish head, and a power source and a control module are arranged in the rigid fish head; the head end of the rigid fish body is connected with the rigid fish head; the flexible fish tail is connected with the rigid fish body, and the flexible fish tail comprises an elastic fish tail spine, a fish tail supporting joint, a tension spring and a flexible fish tail skin; the flexible fishtail driving module is arranged in the rigid fish body; wherein the flexible fishtail is driven by a single motor in cooperation with a stay wire, an intermuscular bone of a fish is simulated through a fishtail supporting joint, the swinging posture of the flexible fishtail is restrained while the driving stay wire is supported, and a nonlinear module is formed through a tension spring and an elastic fishtail spine. The intelligent flexible bionic robotic fish has the advantages that the energy consumption is reduced, and the swimming speed and the swimming efficiency can be improved.

Description

Technical Field

[0001] The present invention relates to the technical field of mechanical manufacturing and bionic robot fish, and in particular to a wire-driven bionic flexible robot fish and a method for using the same. Background Art

[0002] At present, with the gradual deepening of the development of marine resources, underwater robots have become an important tool for human beings to explore the ocean. It is particularly important to develop and design underwater robots that can adapt to various complex seabed environments. However, the movement performance of bionic robot fish designed based on bionic theory is still incomparable to the efficient propulsion method formed by marine fish that have undergone hundreds of millions of years of natural evolution. How to learn the efficient movement mechanism of marine fish and design and develop low-energy and high-efficiency drive structures to achieve high efficiency and high maneuverability of robots has become a key issue that needs to be solved urgently. In particular, the drive structure that achieves the unity of low energy consumption and high maneuverability is still a bottleneck problem recognized at home and abroad.

[0003] At present, researchers at home and abroad have tried to use multi-motor series drive or single motor with different types of rods, hinges, eccentric cams and other rigid drive mechanisms to achieve the movement of bionic robot fish. The relevant results have shown that compared with traditional propeller-driven robots, these drives have advantages such as high propulsion efficiency and good maneuverability, and have shown relatively good performance in actual use. However, these rigid bionic robot fish also have defects such as large size, difficulty in achieving flexible movement, slow response speed, and propulsion efficiency that is difficult to match real biological creatures. There are still many problems in terms of service life, control and maneuverability. How to realize intelligent flexible bionic robot fish more realistically, while reducing energy consumption and improving swimming speed and efficiency, has become a research direction for further developing bionic robot fish.

[0004] In summary, there is at least one of the following technical problems:

[0005] Rigid bionic robot fish have large size and rigid structure, making it difficult to achieve flexible movement comparable to real fish, and have poor maneuverability in complex underwater environments.

[0006] The existing bionic robot fish has a complex driving structure, which makes control more difficult and affects propulsion efficiency and energy utilization. There are still problems with its service life and control maneuverability.

[0007] How to more realistically realize intelligent flexible bionic robot fish, while reducing energy consumption and improving swimming speed and efficiency. Summary of the invention

[0008] The main purpose of the present invention is to provide a wire-driven bionic flexible robotic fish and a method for using the same, so as to solve the problems in the prior art that the rigid bionic robotic fish has complex structure rigidity, large size, difficulty in achieving flexible movement, poor maneuverability, and is difficult to match the real biological creatures in terms of bionic effect. In terms of propulsion performance, the control operability is poor, and the propulsion efficiency and energy utilization are low. How to realize the intelligent flexible bionic robotic fish more realistically and improve the swimming speed and swimming efficiency while reducing energy consumption.

[0009] In order to achieve the above object, according to one aspect of the present invention, a wire-driven bionic flexible robotic fish is provided, comprising:

[0010] A rigid fish head, wherein a power supply and a control module are arranged inside the rigid fish head;

[0011] A rigid fish body, wherein the first end of the rigid fish body is connected to the rigid fish head;

[0012] A flexible fish tail, the flexible fish tail is connected to the rigid fish body, and the flexible fish tail comprises an elastic fish tail spine, a fish tail support joint, a tension spring and a flexible fish tail outer skin;

[0013] A flexible fish tail driving module, wherein the flexible fish tail driving module is arranged inside the rigid fish body;

[0014] Among them, the flexible fishtail is driven by a single motor and a pull wire. The fishtail support joint simulates the intermuscular bone of fish, supports the driving pull wire and constrains the swinging position of the flexible fishtail. A nonlinear module is formed by a tension spring and an elastic fishtail spine.

[0015] Preferably, it also includes a rigid fish body hatch cover, and the rigid fish body hatch cover is arranged on the rigid fish body.

[0016] Preferably, the flexible fishtail driving module comprises:

[0017] A dual-axis DC motor, wherein the dual-axis DC motor is arranged inside the rigid fish body;

[0018] An upper synchronous belt driving wheel, wherein the upper synchronous driving wheel is connected to one end of the dual-axis DC motor;

[0019] An upper synchronous belt, wherein the upper synchronous belt is connected to an upper synchronous belt driving wheel;

[0020] An upper synchronous belt driven wheel, wherein the upper synchronous belt driven wheel is connected to the upper synchronous belt;

[0021] An upper tensioning device, wherein the upper tensioning device is connected to the upper synchronous belt;

[0022] A driven shaft, one end of which is connected to the driven wheel of the upper synchronous belt;

[0023] An upper bearing seat, wherein the upper bearing seat and the sleeve are arranged on the driven shaft;

[0024] An upper winding drum, wherein the upper winding drum is arranged on the driven shaft;

[0025] An upper pull wire is connected to an upper winding drum.

[0026] Preferably, the flexible fishtail driving module further includes:

[0027] A lower synchronous belt driving wheel, wherein the lower synchronous driving wheel is connected to the other end of the dual-axis DC motor;

[0028] A lower synchronous belt, wherein the lower synchronous belt is connected to a lower synchronous belt driving wheel;

[0029] A lower synchronous belt driven wheel, wherein the lower synchronous belt driven wheel is connected to the lower synchronous belt;

[0030] A lower tensioning device, wherein the lower tensioning device is connected to the lower synchronous belt;

[0031] A driven shaft, the other end of which is connected to a lower synchronous belt driven wheel;

[0032] A lower bearing seat, wherein the lower bearing seat and the sleeve are arranged on the driven shaft;

[0033] A lower winding drum, wherein the lower winding drum is arranged on the driven shaft;

[0034] A lower pull-down wire is connected to a lower winding drum.

[0035] Preferably, the upper tensioning device comprises:

[0036] A slide, the slide being slidably matched with a slide groove inside the rigid fish body;

[0037] An upper tensioning wheel, wherein the upper tensioning wheel is connected to the slide;

[0038] A tensioning bolt connected to the slide;

[0039] A tensioning bolt base, the tensioning bolt base being arranged on an upper tensioning device base;

[0040] A tensioning nut cooperates with the tensioning bolt and the tensioning bolt base.

[0041] Preferably, the flexible fish tail comprises:

[0042] A semi-conical shell, wherein the semi-conical shell is provided with a second connecting hole;

[0043] A skeleton cavity, wherein the skeleton cavity is arranged in a semi-conical shell;

[0044] A hollow cavity, wherein the hollow cavity is disposed in the semi-conical shell;

[0045] A front end connecting thin plate, wherein the front end connecting thin plate is arranged at the front end of the semi-conical shell;

[0046] A tail connecting boss, wherein the tail connecting boss is arranged at the rear end of the semi-conical shell;

[0047] A semi-elliptical rib plate, wherein the semi-elliptical rib plate is arranged in a semi-conical shell, and a wire pulling hole 1 is provided on the semi-elliptical rib plate;

[0048] A through slot 1, wherein the through slot 1 is arranged on the front connecting thin plate;

[0049] A second through groove, wherein the second through groove is arranged on the semi-elliptical rib plate;

[0050] A connecting hole 1, wherein the connecting hole 1 is arranged at the front end connecting plate.

[0051] Preferably, it also includes:

[0052] An upper tension spring connected to the boss 1 and the boss 3;

[0053] A lower tension spring connected to the boss 1 and the boss 3;

[0054] An elastic fishtail spine, wherein the elastic fishtail spine is arranged in parallel between the upper tension spring and the lower tension spring;

[0055] The front end fishtail support joint is located at the front end of the flexible fishtail.

[0056] A middle fishtail support joint, wherein the middle fishtail support joint is arranged in the middle of the flexible fishtail;

[0057] A terminal fishtail support joint, wherein the terminal fishtail support joint is arranged at the end of the flexible fishtail;

[0058] Among them, the front fishtail support joint, the middle fishtail support joint and the terminal fishtail support joint are fixedly connected to the elastic fishtail spine in sequence from the front end to the rear end of the flexible fishtail; the upper pull wire, the lower pull wire, the upper pull spring, the lower pull spring, the elastic fishtail spine, the front fishtail support joint, the middle fishtail support joint, and the terminal fishtail active joint together constitute a nonlinear module.

[0059] Preferably, it also includes:

[0060] Boss one, the boss one is arranged on the front end fishtail support joint, and the boss one is connected to the front ends of the upper tension spring and the lower tension spring;

[0061] Boss 2, wherein the boss 2 is arranged on the end fishtail support joint;

[0062] Boss three, the boss three is arranged on the end fishtail support joint, and the boss three is connected to the rear ends of the upper tension spring and the lower tension spring;

[0063] A second pull-wire hole, the second pull-wire hole being arranged on the front end fishtail support joint;

[0064] A through slot three, wherein the through slot three is arranged on the front end fishtail support joint;

[0065] A through slot four, wherein the through slot four is arranged on the end fishtail support joint;

[0066] A wire drawing groove, which is arranged on the end fishtail support joint;

[0067] A pull wire fixing hole is provided on the end fishtail support joint.

[0068] Preferably, it also includes:

[0069] A flexible tail fin connecting plate, wherein the flexible tail fin connecting plate is connected to the flexible fish tail;

[0070] A crescent-shaped flexible tail fin is connected to a flexible tail fin connecting plate.

[0071] According to another aspect of the present invention, a method for using a wire-driven bionic flexible robotic fish is provided, comprising:

[0072] The body curve of a normal fish swimming is simulated by the coordination of the pull line and the elastic fish tail spine, while the fish tail support joint simulates the fish intermuscular bone;

[0073] By using the elastic fishtail spine in conjunction with the tension spring, a fast response is achieved through a nonlinear mechanism, in which the upper and lower tension springs are always in a pre-stretched state. Through the negative stiffness elastic element, when the bionic fishtail swings to both sides, the elastic potential energy of the spring is converted into mechanical energy during the swing.

[0074] The application of the technical solution of the present invention has the following technical effects:

[0075] By coordinating the pull line with the elastic fishtail spine, the bionic fish can simulate the body curve of a normal fish when swimming. At the same time, its fishtail support joint can simulate the fish's intermuscular bone and support the muscle pull line of the bionic fish. Compared with the traditional multi-joint servo series drive, this drive form is simple and easy to control, and at the same time, it makes the bionic fish's body more maneuverable and easier to operate in a more complex environment. The driving pull line and the elastic fishtail spine cooperate. When the pull line drives the flexible fishtail end to bend, the fishtail swing arc can be made smoother. At the same time, the fishtail support joint can also constrain the fishtail swing posture and support the pull line, so that the bionic fishtail can better simulate the swing curve of the real fishtail when swimming, with stronger maneuverability, and easier to operate in a more complex environment. Compared with the traditional multi-joint servo series drive, since this structure is a single-motor drive, only one motor needs to be controlled to achieve a simple and compact effect.

[0076] Through the combination of rope direct drive and force sensor, the driving speed and driving force of the bionic fish can be precisely controlled while ensuring the driving structure is simple and compact, achieving high energy conversion efficiency and utilization, so that the robot fish can obtain longer endurance and longer swimming distance under the same energy supply. Since the flexible fishtail drive module is a pull-wire direct drive without a complex multi-stage transmission structure, it will reduce the energy loss caused by multi-stage transmission while ensuring the driving structure is simple and compact, achieving high energy conversion efficiency and utilization, so that the robot fish can obtain longer endurance and longer swimming distance under the same energy supply.

[0077] By using an elastic fishtail spine in conjunction with a tension spring, a nonlinear mechanism is introduced to overcome the shortcoming of slow response speed of traditional bionic fish. The upper and lower tension springs are always in a pre-stretched state. Due to the introduction of negative stiffness elastic elements, when the bionic fishtail swings to both sides, the elastic potential energy of the spring is converted into mechanical energy during swinging, allowing the bionic fish to achieve a larger and faster motion response while overcoming a smaller energy barrier, thereby swimming faster and more efficiently at the same power consumption.

[0078] The wire-drive system generates less noise during operation. Compared with traditional multi-motor-driven and propeller-driven robot fish, it can swim more quietly when working underwater and is not easily detected by aquatic organisms or other monitoring equipment, which is conducive to underwater monitoring, marine life research and other work.

[0079] The tail shell and tail fin of the flexible bionic robot fish are cast in a mold using polymer materials such as silicone, which can restore the swimming posture of real fish to a large extent, greatly improving the flexibility and maneuverability of the bionic fish mechanism. At the same time, the streamlined dynamic structure can also reduce the swimming resistance of the bionic fish and reduce energy consumption. BRIEF DESCRIPTION OF THE DRAWINGS

[0080] The drawings constituting a part of the present application are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0081] Figure 1 A schematic diagram of the structure of a wire-driven bionic flexible robotic fish according to the present invention is shown;

[0082] Figure 2 Shows Figure 1 Schematic diagram of the driving device structure;

[0083] Figure 3 Shows Figure 1 Schematic diagram of the nonlinear module structure in;

[0084] Figure 4 Shows Figure 1 Schematic diagram of the flexible fishtail structure on the left;

[0085] Figure 5 Shows Figure 1 A schematic diagram of the tensioning device structure;

[0086] Figure 6 Shows Figure 1 Schematic diagram of the fishtail support joint structure;

[0087] Figure 7 Shows Figure 1 Schematic diagram of the rigid fish head structure;

[0088] Figure 8 Shows Figure 1 Schematic diagram of the bionic robotic fish swimming.

[0089] The above drawings include the following reference numerals:

[0090] 1. Rigid fish head, 101. Power supply, 102. Control module;

[0091] 2. Rigid fish body, 201. Upper tensioning device base, 202. Motor bracket, 203. Lower tensioning device base;

[0092] 3. Rigid fish hatch cover;

[0093] 4. flexible fishtail, 401. skeleton cavity, 402. hollow cavity, 403. wire drawing hole 1, 404. through slot 1, 405. semi-elliptical rib, 406. through slot 2, 407. front end connecting thin plate, 408. connecting hole 1, 409. connecting hole 2, 410. tail connecting boss, 411. semi-conical shell;

[0094] 501, flexible tail fin connecting plate, 502, crescent-shaped flexible tail fin;

[0095] 6. Flexible fishtail drive module, 601. Double-axis DC motor, 602. Upper synchronous belt, 603. Lower synchronous belt, 604. Upper synchronous belt driving wheel, 605. Lower synchronous belt driving wheel, 606. Upper synchronous belt driven wheel, 607. Lower synchronous belt driven wheel, 608. Upper bearing seat, 609. Lower bearing seat, 610. Upper winding drum, 611. Lower winding drum, 612. Driven shaft, 613. Upper pull wire, 614. Lower pull wire, 62. Upper tensioning device, 621. Upper tensioning wheel, 622. Slide, 623. Tensioning bolt base, 624. Tensioning bolt, 625. Tensioning nut, 626. Fixing screw, 627. Gasket, 63. Lower tensioning device;

[0096] 7. Nonlinear module, 701. Upper tension spring, 702. Lower tension spring, 703. Elastic fishtail spine, 721. Front end fishtail support joint, 7211. Wire drawing hole two, 7212. Through slot three, 7213. Boss one, 722. Middle fishtail support joint, 723. End fishtail active joint, 7231. Boss two, 7232. Through slot four, 7233. Boss three, 7234. Wire drawing groove, 7235. Wire drawing fixing hole. DETAILED DESCRIPTION

[0097] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0098] like Figures 1 to 8 As shown, an embodiment of the present invention provides a wire-driven bionic flexible robotic fish, comprising: a rigid fish head 1, wherein a power supply 101 and a control module 102 are provided in the rigid fish head 1; a rigid fish body 103, wherein the head end of the rigid fish body 103 is connected to the rigid fish head 1; a flexible fish tail 4, wherein the flexible fish tail 4 is connected to the rigid fish body 103, and the flexible fish tail 4 comprises an elastic fish tail spine 703, a fish tail support joint, a tension spring and a flexible fish tail 4 outer skin; a flexible fish tail drive module 6, wherein the flexible fish tail drive module 6 is arranged inside the rigid fish body 103; wherein the flexible fish tail 4 is driven by a single motor in cooperation with a pull wire, and the fish tail support joint simulates the intermuscular bone of the fish to support the muscle-pull wire of the bionic fish, while constraining the swinging posture of the flexible fish tail 4, and a nonlinear module 7 is formed by the tension spring and the elastic fish tail spine 703.

[0099] In this embodiment, a power supply 101 and a control module 102 are provided in the rigid fish head 1, a head end of a rigid fish body 103 is connected to the rigid fish head 1, a flexible fish tail 4 is connected to the rigid fish body 103, the flexible fish tail 4 comprises an elastic fish tail spine 703, a fish tail support joint, a tension spring and a flexible fish tail 4 outer skin, the flexible fish tail 4 comprises: a semi-conical shell 411, a connecting hole 2 409 is provided on the semi-conical shell 411, so that the left and right semi-conical shells 411 are connected, a skeleton cavity 401 is arranged in the semi-conical shell 411, a hollow cavity 402 is arranged in the semi-conical shell 411, and a front end connecting thin plate 407 is provided. It is arranged at the front end of the semi-conical shell 411, the tail connecting boss 410 is arranged at the rear end of the semi-conical shell 411, the semi-elliptical rib 405 is arranged in the semi-conical shell 411, and a pull wire hole 403 is provided on the semi-elliptical rib 405 for the upper and lower pull wires 614 to pass through. A through groove 404 is arranged on the front end connecting thin plate 407 for installing the elastic fishtail spine 703. A through groove 406 is arranged on the semi-elliptical rib 405 for the installation of the upper and lower tension springs 702 and the working stroke. A connecting hole 408 is arranged on the front end connecting thin plate 407 to facilitate the connection between the flexible fishtail 4 and the rigid fish body 103. The fishtail support joint includes a front fishtail support joint 721, a middle fishtail support joint 722 and a terminal fishtail support joint, wherein the front fishtail support joint 721 is located at the front end of the flexible fishtail 4, the middle fishtail support joint 722 is arranged in the middle of the flexible fishtail 4, and the terminal fishtail support joint is arranged at the end of the flexible fishtail 4; wherein the front fishtail support joint 721, the middle fishtail support joint 722 and the terminal fishtail support joint are fixedly connected to the elastic fishtail spine 703 in sequence from the front end to the rear end of the flexible fishtail 4; and further includes a boss 1 7213, wherein the boss 1 7213 is arranged on the front fishtail support joint 721; a boss 2 7231 , the boss two 7231 is arranged on the end fishtail support joint; the boss three 7233, the boss three 7233 is arranged on the end fishtail support joint; the wire hole two 7211, the wire hole two 7211 is arranged on the front end fishtail support joint 721; the front ends of the upper tension spring 701 and the lower tension spring 702 are connected to the boss one 7213, and the rear ends of the upper tension spring 701 and the lower tension spring 702 are connected to the boss three 7233; the upper tension spring 701, the lower tension spring 702, the elastic fishtail spine 703 and the front end fishtail support joint 721, the middle fishtail support joint 722, and the end fishtail active joint 723 together constitute the nonlinear module 7. A through slot three 7212, wherein the through slot three 7212 is arranged on the front end fishtail support joint 721; a through slot four 7232, wherein the through slot four 7232 is arranged on the terminal fishtail support joint; a wire pulling slot 7234, wherein the wire pulling slot 7234 is arranged on the terminal fishtail support joint; a wire pulling fixing hole 7235, wherein the wire pulling fixing hole 7235 is arranged on the terminal fishtail support joint, and is used to fix the wire pulling at the terminal of the fishtail.

[0100] In this embodiment, the flexible fishtail drive module 6 is arranged inside the rigid fish body 103; the flexible fishtail 4 is driven by a single motor and a pull wire, the motor bracket 202 is used to support the motor, and the fishtail support joint simulates the intermuscular bone of the fish to support the muscle-pull wire of the bionic fish, and a nonlinear module 7 is formed by a tension spring and an elastic fishtail spine 703. The flexible fishtail drive module 6 includes: a dual-axis DC motor 601, which is arranged inside the rigid fish body 103; an upper synchronous belt driving wheel 604, which is connected to one end of the dual-axis DC motor 601; an upper synchronous belt 602, which is connected to the upper synchronous belt driving wheel 604; an upper synchronous belt driven wheel 606, which is connected to the upper synchronous belt 602; an upper tensioning device 62 is connected to the upper synchronous belt 602, and one end of the driven shaft 612 is connected to the upper synchronous belt driven wheel 606; an upper bearing seat 608 is sleeved on the driven shaft 612, and an upper winding drum 610 is arranged on the driven shaft 612; an upper pull wire 613 is connected to the upper winding drum 610. The lower synchronous driving wheel is connected to the other end of the dual-axis DC motor 601, and the lower synchronous belt 603 is connected to the lower synchronous belt driving wheel 605; the lower synchronous belt driven wheel 607, the lower synchronous belt driven wheel 607 is connected to the lower synchronous belt 603; the lower tensioning device 63, the lower tensioning device 63 is connected to the lower synchronous belt 603, the other end of the driven shaft 612 is connected to the lower synchronous belt driven wheel 607, the lower bearing seat 609 is sleeved on the driven shaft 612, and the lower winding drum 611 is set on the driven shaft 612; the lower pull wire 614, the lower pull wire 614 is connected to the lower winding drum 611.

[0101] In this embodiment, the rigid fish body hatch cover 3 is arranged on the rigid fish body 103, and the upper tensioning device 62 includes: a slide 622, the slide 622 is slidably matched with the slide groove inside the rigid fish body 103, the upper tensioning wheel 621 is connected to the slide 622, the base 623 of the tensioning bolt 624 is arranged on the base 201 of the upper tensioning device 62, the tensioning nut 625 and the tensioning bolt 624 are arranged on the base 623 of the tensioning bolt 624, and the end of the tensioning bolt 624 is connected with the slide 622 under the matching connection of the tensioning nut 625. The flexible tail fin connecting plate 501 is connected to the flexible fish tail 4; the crescent-shaped flexible tail fin 502 is connected to the flexible tail fin connecting plate 501.

[0102] The flexible fishtail 4 in the present invention is driven by a single motor in combination with a cable, and the fishtail support joint simulates the intermuscular bone of fish, so as to achieve precise control of the driving force and driving speed, and achieve high energy conversion efficiency while maintaining a simple and compact structure. The nonlinear module 7 is formed by the interaction between the tension spring and the elastic fishtail spine 703, which overcomes the disadvantage of the slow response speed of traditional bionic fish, simulates the swimming of fish more realistically, achieves faster swimming speed, higher propulsion efficiency and better body flexibility, so that the flexible bionic robot fish can still maintain efficient operation capabilities in complex water environments.

[0103] The present invention takes reducing energy consumption, improving the maneuverability and flexibility of underwater bionic robots, and accelerating the swimming speed and swimming efficiency as the starting point, and designs a set of line-driven nonlinear flexible fish tail 4 devices. Compared with complex multi-stage transmission mechanisms, the rope direct drive is simple, compact, and has the characteristics of low energy loss. While ensuring the flexibility and maneuverability of the bionic fish body, an elastic element and an elastic spine are arranged on the fish tail to introduce a nonlinear mechanism, thereby reducing the energy barrier when the bionic fish swings, and overcoming the shortcoming of the slow response speed of traditional bionic fish. The upper and lower tension springs 702 are always in a pre-stretched state. Due to the introduction of negative stiffness elastic elements, when the bionic fish tail swings to both sides, the elastic potential energy of the spring is converted into mechanical energy during the swing, so that the bionic fish can achieve a larger and faster motion response and increase the swimming speed while overcoming a smaller energy barrier, thereby realizing a more efficient design of a line-driven bionic flexible robot fish.

[0104] Specifically, the present embodiment includes a rigid fish head 1, a rigid fish body 103, a rigid fish body hatch cover 3, a flexible fish tail 4, a flexible tail fin, a flexible fish tail drive module 6 and a nonlinear module 7; wherein, a power supply 101 and a control module 102 are provided in the rigid fish head 1, the flexible fish tail drive module 6 is arranged inside the rigid fish body 103, the rigid fish body hatch cover 3 is arranged on the rigid fish body 103, and the end of the rigid fish head 1 is sealedly connected to the head end of the rigid fish body 103; a nonlinear module 7 is provided inside the flexible fish tail 4, the head end of the flexible fish tail 4 is sealedly connected to the end of the rigid fish body 103, and the end of the flexible fish tail 4 is sealedly connected to the flexible tail fin, and under the intelligent control of the control module 102, the flexible fish tail drive module 6 drives the flexible fish tail 4 to complete the swinging action. The flexible fishtail drive module 6 includes a dual-axis DC motor 601, an upper synchronous belt 602, a lower synchronous belt 603, an upper synchronous belt driving wheel 604, a lower synchronous belt driving wheel 605, an upper synchronous belt driven wheel 606, a lower synchronous belt driven wheel 607, an upper tensioning device 62, a lower tensioning device 63, an upper tensioning device base 201, a lower tensioning device base 203, a driven shaft 612, an upper winding drum 610, a lower winding drum 611, and an upper pull wire 613. and the lower pull line 614, the upper bearing seat 608 and the lower bearing seat 609; the double-axis DC motor 601 is inserted into the motor groove inside the rigid fish body 103, and the upper synchronous belt driving wheel 604 is fixedly connected to the upper end of the output shaft of the double-axis DC motor 601; the upper tensioning device 62 is arranged on the upper tensioning device 62 base 201 in the rigid fish body 103; the upper winding drum 610 is fixedly installed at the first step at the upper end of the driven shaft 612, and the driven shaft 612 The upper bearing seat 608 is installed at the second step at the upper end, and the base of the upper bearing seat 608 is fixedly connected to the upper boss in the rigid fish body 103; the upper synchronous belt driven wheel 606 is fixedly connected to the third step at the upper end of the driven shaft 612; the upper synchronous belt 602 passes around the upper synchronous belt driving wheel 604, the upper synchronous belt driven wheel 606 and the upper tensioning wheel 621 for transmission; the upper pull line 613 passes around the upper winding drum 610, and its two ends are respectively fixedly connected to the two sides of the end of the flexible fish tail 4; the lower synchronous belt 603, the lower synchronous belt driving wheel 605, the lower synchronous belt driven wheel 607, the lower tensioning device 63, the lower winding drum 611, the lower bearing seat 609 and the lower pull line 614 are arranged completely symmetrically with the corresponding upper parts above; the upper pull line 613 and the lower pull line 614 together with the upper tension spring 701, the lower tension spring 702, the elastic fish tail spine 703 and the fish tail support joint constitute a nonlinear module 7;The fishtail support joint includes a front-end fishtail support joint 721, a middle fishtail support joint 722 and a terminal fishtail active joint 723. The front-end fishtail support joint 721 is arranged at the front end of the flexible fishtail 4 and is fixedly connected to the elastic fishtail spine 703. The upper and lower parts of the front-end fishtail support joint 721 and the terminal fishtail active joint 723 are respectively provided with a boss 1 7213 and a boss 3 7233. The two ends of the upper spring are respectively connected to the boss 1 7213 of the front-end fishtail support joint 721 and the boss 3 7233 of the terminal fishtail active joint 723. The lower spring and the upper spring are symmetrically arranged, and the upper spring and the lower spring are always kept in a pre-stretched state. One end of the elastic fishtail spine 703 is inserted into the end through slot of the rigid fish head 1 and fixedly connected by bolts. The other end is inserted into the terminal fishtail active joint 723 and fixedly connected by bolts; when the flexible fishtail drive module 6 is running, the dual-axis DC motor 601 starts to operate under the drive of the control module 102, driving the upper synchronous belt driving wheel 604 and the lower synchronous belt driving wheel 605 to rotate, and under the action of the upper tensioning device 62 and the lower tensioning device 63, the upper synchronous belt driven wheel 606 and the lower synchronous belt driven wheel 607 are driven for transmission. Under the fixation of the upper and lower bearing seats 609, since the upper and lower synchronous belt driven wheels 607 are fixedly connected to the driven shaft 612, the driven shaft 612 is driven for transmission, and then the upper winding drum 610 and the lower winding drum 611 fixed on the driven shaft 612 are driven to rotate, driving the pull wire to the left or right to drive the flexible fishtail 4 to swing left and right. Due to the effect of the nonlinear module 7, the upper and lower tension springs 702 are always in a pre-stretched state. With the introduction of the negative stiffness elastic element, when the bionic fish tail swings to both sides, the elastic potential energy of the spring is converted into mechanical energy during the swing, so that the bionic fish can achieve a larger and faster motion response while overcoming a smaller energy barrier, thereby improving the swimming speed and swimming efficiency of the bionic fish. ;

[0105] Specifically, the flexible fish tail 4 is a split structure, which is divided into a left fish tail and a right fish tail that are completely symmetrical on the left and right. The internal structures of the left fish tail and the right fish tail are also completely symmetrical. The left fish tail includes a semi-conical shell 411, a front connecting thin plate 407, a tail connecting boss 410, a skeleton cavity 401 for placing a fish tail support joint, and a hollow hollow cavity 402, wherein the skeleton cavity 401 is used to place the fish tail support joint, and the hollow cavity 402 is to reduce the weight of the fish body and to place a counterweight to meet the needs of the fish body to float and dive. The front connecting thin plate 407, the semi-conical shell 411 and the tail connecting boss 410 are integrated. The inner diameters of the skeleton cavity 401 and the hollow cavity 402 gradually decrease from the front end of the flexible fish tail 4 to the rear, which is used to simulate the streamlined fish body structure of the fish. A longitudinally parallel semi-elliptical rib 405 is provided between the skeleton cavity 401 and the hollow cavity 402, and the semi-elliptical rib 405 connects the skeleton cavity 401 is separated from the hollow cavity 402, and a through groove 404 is opened in the center of the front end connecting thin plate 407 and the center of the semi-elliptical rib 405 for connecting with the elastic fish tail spine 703. Two pulling wire holes 403 are opened near the through groove 404 for the pulling wire to pass through, and a connecting hole 408 fixed to the rigid fish body 103 is provided on the outer edge of the front end connecting thin plate 407, and a through groove 2 406 for placing the upper tension spring 701 and the lower tension spring 702 is opened on the upper and lower sides of the through groove 1 404, and the working stroke of the upper and lower tension springs 702 is reserved, the width of the through groove 2 406 along the cross-sectional direction of the flexible fish tail 4 gradually decreases from the front end of the flexible fish tail 4 to the rear, and a groove is provided in the middle of the tail connecting boss 410 for connecting with the tail fin connector, and a connecting hole 2 409 is opened on the hollow cavity 402 of the flexible fish tail 4 and on the tail solid plate of the flexible fish tail 4 so that the left and right semi-conical shells 411 can be connected. The flexible tail fin comprises a flexible tail fin connecting plate 501 and a crescent-shaped flexible tail fin 502 . The front and rear parts of the flexible tail fin connecting plate 501 are respectively provided with connecting holes for connecting with the flexible fish tail 4 and the crescent-shaped flexible tail fin 502 .

[0106] Specifically, the upper tensioning device 62 includes an upper tensioning wheel 621, a slide 622, a tensioning bolt 624, a tensioning bolt 624 base 623, a tensioning nut 625, a gasket 627, and a fixing screw 626. The slide 622 can slide in the slide groove in the upper tensioning device 62 base 201 inside the rigid fish body 103. The tensioning bolt 624 base 623 is fixed on the upper tensioning device 62 base 201 in the rigid fish body 103. A groove for placing the tensioning nut 625 and a through hole for the tensioning bolt 624 to pass through are opened on the tensioning bolt 624 base 623. The tensioning bolt 62 4 passes through the through hole to cooperate with the nut, and its end is pressed against the slide 622. The upper tensioning wheel 621 is fixed to the slide 622 through the gasket 627 and the fixing screw 626. When installing the flexible fishtail drive module 6, if the upper synchronous belt 602 is relatively loose, the slide 622 can be pushed inward by adjusting the tensioning bolt 624, thereby driving the upper tensioning wheel 621 to move inward, so that the upper synchronous belt 602 can be pre-tightened to prevent the synchronous belt from slipping and affecting the driving effect when the drive device is transmitting. The lower tensioning device 63 and the upper tensioning device 62 have the same structure and are symmetrically arranged.

[0107] Specifically, the rigid fish head 1, the rigid fish body 103 and the rigid fish body hatch cover 3 are made by photosensitive resin 3D printing, the flexible fish tail 4 and the crescent-shaped flexible tail fin 502 are made by casting in a mold using a polymer flexible material, and can be bent repeatedly, and the elastic fish tail spine 703 and the flexible tail fin connecting plate 501 are made of polyurethane material and have a certain elasticity. The rigid fish head 1 and the rigid fish body 103, the rigid fish body 103 and the rigid fish body hatch cover 3, the rigid fish body 103 and the flexible fish tail 4, the left fish tail and the right fish tail, and the flexible fish tail 4 and the flexible tail fin are all fixedly connected by bolts, and the connection parts are sealed with waterproof sealant to prevent water from seeping into the fish body.

[0108] Specifically, the fishtail support joints include three types, namely, the front fishtail support joint 721, the middle fishtail support joint 722 and the terminal fishtail active joint 723; the front fishtail support joint 721 and the middle fishtail support joint 722 are both hollow structures to reduce unnecessary weight, and a through slot 3 7212 of the same size as the through slot 1 404 is opened in the center of both for installing the elastic fishtail spine 703, and an X-shaped bracket extends outward from the through slot 3 7212 and is connected to the elliptical outer frame, and a wire hole 2 7211 of the same size as the wire hole 1 403 is opened on the X-shaped bracket for the wire to pass through and play a supporting role, the difference is that the through slot 3 721 of the front fishtail support joint 721 is not provided. 12 symmetrically provided with boss one 7213 on the upper and lower sides, an optical axis is provided in the boss one 7213 and is connected with one end of the upper tension spring 701 and the lower tension spring 702; the terminal fishtail active joint 723 is a solid structure, with a boss two 7231 in the center, in which a through groove four 7232 is dug for fixing the end of the elastic fishtail spine 703 to the fish body, boss two 7231 symmetrically provided with boss three 7233 with an optical axis on the upper and lower sides, connected with the upper tension spring 701 and the other end of the lower tension spring 702, four wire drawing grooves 7234 are symmetrically opened on the left and right sides of the boss two 7231, and a wire drawing fixing hole 7235 is opened on the side of the wire drawing groove 7234, and the wire drawing wire can be fixedly connected with a top screw. The front tail support joint 721, the middle tail support joint 722 and the end tail active joint 723 are evenly fixed on the elastic tail spine 703. Under the action of the tail support joint, the swinging position of the flexible tail 4 is controlled, and the upper and lower pull lines 614 are supported. The appearance of the line-driven nonlinear flexible release robot fish of the present invention is modeled in proportion to the body of a real fish, and the streamlined appearance is designed to reduce the swimming resistance and increase the maximum swimming speed.

[0109] The working principle of the present invention is as follows:

[0110] When the fishtail swings to the left, the control module 102 controls the flexible fishtail drive module 6 to work after the power supply 101 is turned on. The dual-axis DC motor 601 rotates counterclockwise to drive the upper synchronous belt driving wheel 604 and the lower synchronous belt driving wheel 605 to rotate, and then drives the upper synchronous belt 602 and the lower synchronous belt 603 to transmit. Under the action of the upper tensioning device 62 and the lower tensioning device 63, the upper synchronous belt driven wheel 606 and the lower synchronous belt driven wheel 607 are driven to rotate counterclockwise, thereby driving the driven shaft 612 to rotate counterclockwise, and the driven shaft 612 fixed to the driven shaft 612 is rotated. The upper winding drum 610 and the lower winding drum 611 also drive the left side of the upper pull wire 613 and the lower pull wire 614 to contract and the right side to stretch as the driven shaft 612 drives them. Under the action of the two pull wires, the terminal fishtail active joint 723 swings to the left and bends to the left with the elastic fishtail spine 703. At this time, the upper tension spring 701 and the lower tension spring 702, which were originally in a pre-stretched state, contract as the fishtail swings to the left, and the stored elastic potential energy is converted into the kinetic energy of the fishtail swing. At the same time, the elastic fishtail spine 703 with elastic properties converts mechanical energy into elastic potential energy. It is gradually stored, and as the fishtail swings to the maximum position, the elastic potential energy of the upper tension spring 701 and the lower tension spring 702 reaches the minimum value, while the elastic potential energy of the elastic fishtail spine 703 reaches the maximum value; when the fishtail swings back to the right, as the dual-axis DC motor 601 reverses clockwise, the right side lines of the upper tension wire 613 and the lower tension wire 614 gradually shrink, and the elastic potential energy stored in the elastic fishtail spine 703 is released and converted into the kinetic energy of the fishtail swinging to the right and the elastic potential energy in the upper spring and the lower spring until the fishtail reaches the horizontal straight line position; and when the fishtail swings back to the right, When continuing to swing to the right beyond the horizontal position, the above process is carried out in the opposite direction. In this way, under the joint action of the elastic fishtail spine 703, the upper tension spring 701 and the lower tension spring 702, the fishtail can effectively convert and store the energy inside the system during the swinging process, so that the bionic fish can swing faster, that is, it swings faster, and when the fishtail passes the horizontal position, the converted energy can be utilized to achieve a greater response. The above process is performed alternately to realize the continuous swinging motion of the wire-driven bionic flexible robotic fish of the present invention.

[0111] Another embodiment of the present invention provides a method for using a wire-driven bionic flexible robotic fish, comprising:

[0112] The body curve of a normal fish swimming is simulated by cooperating with the elastic fishtail spine 703 through the pull line, and the fishtail support joint is used to simulate the fish intermuscular bone;

[0113] The elastic fishtail spine 703 is used in conjunction with the tension spring to achieve a fast response through a nonlinear mechanism, wherein the upper and lower tension springs 702 are always in a pre-stretched state. Through the negative stiffness elastic element, when the bionic fishtail swings to both sides, the elastic potential energy of the spring is converted into mechanical energy during the swing.

[0114] From the above description, it can be seen that the above embodiments of the present invention have the following technical effects:

[0115] 1. By matching the pull line with the elastic fishtail spine 703, the bionic fish can simulate the body curve of a normal fish when swimming. At the same time, its fishtail support joint can simulate the fish's intermuscular bone and support the muscle pull line of the bionic fish. Compared with the traditional multi-joint servo series drive, this drive form is simple and easy to control, and at the same time, the bionic fish has stronger body mobility and can be operated more easily in a more complex environment. The driving pull line and the elastic fishtail spine 703 are matched. When the pull line drives the flexible fishtail 4 to bend at the end, the fishtail swing arc can be made smoother. At the same time, the fishtail support joint can also play the role of constraining the fishtail swing posture and supporting the pull line, so that the bionic fishtail can better simulate the swing curve of the real fishtail when swimming, has stronger mobility, and can be operated more easily in a more complex environment. Compared with the traditional multi-joint servo series drive, since this structure is a single motor drive, only one motor needs to be controlled to achieve a simple and compact effect.

[0116] 2. Through direct drive by rope, high energy conversion efficiency and utilization rate are achieved, so that the robot fish can obtain longer endurance and longer swimming distance under the same energy supply. Since the flexible fishtail drive module 6 is directly driven by a pull line and does not have a complex multi-stage transmission structure, it can reduce energy loss caused by multi-stage transmission while ensuring that the drive structure is simple and compact, and achieve high energy conversion efficiency and utilization rate, so that the robot fish can obtain longer endurance and longer swimming distance under the same energy supply.

[0117] 3. By using the elastic fishtail spine 703 in conjunction with the tension spring, a nonlinear mechanism is introduced to overcome the shortcoming of the slow response speed of traditional bionic fish. The upper and lower tension springs 702 are always in a pre-stretched state. Due to the introduction of the negative stiffness elastic element, when the bionic fishtail swings to both sides, the elastic potential energy of the spring is converted into mechanical energy during the swing, so that the bionic fish can achieve a larger and faster motion response while overcoming a smaller energy barrier, thereby swimming faster and more efficiently at the same power consumption.

[0118] 4. The wire drive system generates less noise during operation. Compared with traditional multi-motor drive and propeller drive robot fish, it can swim more quietly when working underwater and is not easily detected by aquatic organisms or other monitoring equipment, which is conducive to the development of underwater monitoring, marine life research and other work.

[0119] 5. The tail shell and tail fin of the flexible bionic robot fish are cast in a mold using polymer materials such as silicone, which can restore the swimming posture of real fish to a large extent, greatly improving the flexibility and maneuverability of the bionic fish mechanism. At the same time, the streamlined dynamic structure can also reduce the swimming resistance of the bionic fish and reduce energy consumption.

[0120] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A wire-driven bionic flexible robotic fish, characterized in that: include: A rigid fish head, wherein a power supply and a control module are arranged inside the rigid fish head; A rigid fish body, wherein the first end of the rigid fish body is connected to the rigid fish head; A flexible fish tail, the flexible fish tail is connected to the rigid fish body, and the flexible fish tail comprises an elastic fish tail spine, a fish tail support joint, a tension spring and a flexible fish tail outer skin; A flexible fish tail driving module, wherein the flexible fish tail driving module is arranged inside the rigid fish body; Among them, the flexible fishtail is driven by a single motor and a pull wire. The fishtail support joint simulates the intermuscular bone of fish, supports the driving pull wire and constrains the swinging position of the flexible fishtail. A nonlinear module is formed by a tension spring and an elastic fishtail spine.

2. The wire-driven bionic flexible robotic fish according to claim 1, characterized in that: It also includes a rigid fish body hatch cover, which is arranged on the rigid fish body.

3. The wire-driven bionic flexible robotic fish according to claim 1, characterized in that: The flexible fishtail driving module comprises: A dual-axis DC motor, wherein the dual-axis DC motor is arranged inside the rigid fish body; An upper synchronous belt driving wheel, wherein the upper synchronous driving wheel is connected to one end of the dual-axis DC motor; An upper synchronous belt, wherein the upper synchronous belt is connected to an upper synchronous belt driving wheel; An upper synchronous belt driven wheel, wherein the upper synchronous belt driven wheel is connected to the upper synchronous belt; An upper tensioning device, wherein the upper tensioning device is connected to the upper synchronous belt; A driven shaft, one end of which is connected to the driven wheel of the upper synchronous belt; An upper bearing seat, wherein the upper bearing seat and the sleeve are arranged on the driven shaft; An upper winding drum, wherein the upper winding drum is arranged on the driven shaft; An upper pull wire is connected to an upper winding drum.

4. The wire-driven bionic flexible robotic fish according to claim 1, characterized in that: The flexible fishtail driving module also includes: A lower synchronous belt driving wheel, wherein the lower synchronous driving wheel is connected to the other end of the dual-axis DC motor; A lower synchronous belt, wherein the lower synchronous belt is connected to a lower synchronous belt driving wheel; A lower synchronous belt driven wheel, wherein the lower synchronous belt driven wheel is connected to the lower synchronous belt; A lower tensioning device, wherein the lower tensioning device is connected to the lower synchronous belt; A lower bearing seat, wherein the lower bearing seat is sleeved on the driven shaft, and the other end of the driven shaft is connected to the driven wheel of the lower synchronous belt; A lower winding drum, wherein the lower winding drum is arranged on the driven shaft; A lower pull-down wire is connected to a lower winding drum.

5. The wire-driven bionic flexible robotic fish according to claim 1, characterized in that: The upper tensioning device comprises: A slide, the slide being slidably matched with a slide groove inside the rigid fish body; An upper tensioning wheel, wherein the upper tensioning wheel is connected to the slide; A tensioning bolt connected to the slide; A tensioning bolt base, the tensioning bolt base being arranged on an upper tensioning device base; A tensioning nut cooperates with the tensioning bolt and the tensioning bolt base.

6. The wire-driven bionic flexible robotic fish according to claim 1, characterized in that: The flexible fish tail comprises: A semi-conical shell, wherein the semi-conical shell is provided with a second connecting hole; A skeleton cavity, wherein the skeleton cavity is arranged in a semi-conical shell; A hollow cavity, wherein the hollow cavity is disposed in the semi-conical shell; A front end connecting thin plate, wherein the front end connecting thin plate is arranged at the front end of the semi-conical shell; A tail connecting boss, wherein the tail connecting boss is arranged at the rear end of the semi-conical shell; A semi-elliptical rib plate, wherein the semi-elliptical rib plate is arranged in a semi-conical shell, and a wire pulling hole 1 is provided on the semi-elliptical rib plate; A through slot 1, wherein the through slot 1 is arranged on the front connecting thin plate; A second through groove, wherein the second through groove is arranged on the semi-elliptical rib plate; A connecting hole 1, wherein the connecting hole 1 is arranged at the front end connecting plate.

7. The wire-driven bionic flexible robotic fish according to claim 1, characterized in that: Also includes: An upper tension spring connected to the boss 1 and the boss 3; A lower tension spring connected to the boss 1 and the boss 3; An elastic fishtail spine, wherein the elastic fishtail spine is arranged in parallel between the upper tension spring and the lower tension spring; The front end fishtail support joint is located at the front end of the flexible fishtail. A middle fishtail support joint, wherein the middle fishtail support joint is arranged in the middle of the flexible fishtail; A terminal fishtail support joint, wherein the terminal fishtail support joint is arranged at the end of the flexible fishtail; Among them, the front fishtail support joint, the middle fishtail support joint and the terminal fishtail support joint are fixedly connected to the elastic fishtail spine in sequence from the front end to the rear end of the flexible fishtail; the upper pull wire, the lower pull wire, the upper pull spring, the lower pull spring, the elastic fishtail spine, the front fishtail support joint, the middle fishtail support joint, and the terminal fishtail active joint together constitute a nonlinear module.

8. The wire-driven bionic flexible robotic fish according to claim 1, characterized in that: Also includes: Boss one, the boss one is arranged on the front end fishtail support joint, wherein the boss one is connected to the front ends of the upper tension spring and the lower tension spring; Boss 2, wherein the boss 2 is arranged on the end fishtail support joint; Boss three, the boss three is arranged on the end fishtail support joint, and the boss three is connected to the rear ends of the upper tension spring and the lower tension spring; A second pull-wire hole, the second pull-wire hole being arranged on the front fishtail support joint; A through slot three, wherein the through slot three is arranged on the front end fishtail support joint; A through slot four, wherein the through slot four is arranged on the end fishtail support joint; A wire drawing groove, which is arranged on the end fishtail support joint; A pull wire fixing hole is provided on the end fishtail support joint.

9. The wire-driven bionic flexible robotic fish according to claim 1, characterized in that: Also includes: A flexible tail fin connecting plate, wherein the flexible tail fin connecting plate is connected to the flexible fish tail; A crescent-shaped flexible tail fin is connected to a flexible tail fin connecting plate.

10. A method for using a wire-driven bionic flexible robotic fish, based on the wire-driven bionic flexible robotic fish according to any one of claims 1 to 9, characterized in that: include: The body curve of a normal fish swimming is simulated by the coordination of the pull line and the elastic fish tail spine, while the fish tail support joint simulates the fish intermuscular bone; By using the elastic fishtail spine in conjunction with the tension spring, a fast response is achieved through a nonlinear mechanism, in which the upper and lower tension springs are always in a pre-stretched state. Through the negative stiffness elastic element, when the bionic fishtail swings to both sides, the elastic potential energy of the spring is converted into mechanical energy during the swing.

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