A line driving artificial fish tail device for high frequency oscillation

Abstract

The utility model relates to underwater robot technical field discloses a kind of line drive imitation fish tail devices for high frequency swing, comprising: series type imitation fish tail structure, including bionic fish tail structure and rigid drive line, rigid drive line is connected with bionic fish tail structure;Line drive mechanism, including sinusoidal device and screw swing adjustment mechanism, sinusoidal device includes sinusoidal device support, recess gear, guide slot and positioning groove, rotate motion of recess gear is converted into left and right linear reciprocating motion of guide slot by sinusoidal device, further realize the back and forth swing of bionic fish tail structure.Screw swing adjustment mechanism, including amplitude modulation screw and amplitude modulation nut, rotate torque transmission by bevel gear to make amplitude modulation screw rotate and realize the movement of amplitude modulation nut, to realize the swing adjustment of imitation fish tail structure.The utility model patent converts the reciprocating swing of fish tail by sinusoidal device for the rotate motion of motor, effectively solve the problem of low frequency of line drive swing.

Description

Technical Field

[0001] This utility model patent relates to the field of underwater robot technology, and in particular to a line-driven fishtail-like device for high-frequency oscillation. Background Technology

[0002] With global economic development, people's demand for resources is increasing. The ocean, rich in biological and mineral resources, has gained attention from countries around the world. However, the harsh environment caused by underwater high pressure and darkness increases the difficulty of exploring the ocean. In recent years, underwater robots have gradually become a popular research field, and more and more underwater robots have been developed, making ocean exploration more convenient.

[0003] Traditional underwater robots are propeller-driven, which provides significant propulsion but suffers from drawbacks such as low efficiency, high noise levels, and environmental unfriendliness. Fish, through millions of years of evolution, possess excellent swimming abilities. With the development of bionics and robotics, biomimetic robotic fish have gained popularity, for example, by mimicking real fish to achieve higher efficiency and better maneuverability.

[0004] Most current robotic fish employ a multi-joint serial drive method, where one motor drives one joint. By controlling the motor parameters, they mimic the body waves of a real fish to achieve biomimetic fish movement. This approach suffers from large fitting errors when the number of joints is small, and excessive control difficulty when the number of joints is large. The proposed linear drive robotic fish makes it possible to mimic fish body waves with fewer motors.

[0005] Most existing wire-driven robotic fish use servo motors to rotate back and forth or motors to rotate in the forward and reverse directions to simulate fish tail wagging. Due to the limitation of motor response speed, this type of robotic fish cannot achieve high-frequency wagging, generally not exceeding 4Hz, making it difficult to achieve high-frequency wagging. Utility Model Content

[0006] The purpose of this invention is to provide a wire-driven, fish-tail-like device that enables high-frequency swimming of robotic fish, thus solving the problem of low swimming frequency in existing wire-driven robotic fish.

[0007] To achieve the above objectives, this utility model provides a line-driven fishtail-like device for high-frequency oscillation, comprising: A series of fish-tail-like structures includes a biomimetic fish-tail structure and a rigid drive line. The fish-tail-like structure is connected to a sine device support. The rigid drive line is connected to the biomimetic fish-tail structure and is fixed to both sides of a guide groove. The guide groove is used to achieve reciprocating tension of the rigid drive line by swinging to realize the reciprocating swing of the series of fish-tail-like structures. The linear drive mechanism includes a sine device and a lead screw amplitude adjustment mechanism. The sine device is connected to the series-connected fishtail structure. The guide groove is the motion output component of the sine device and is connected to the rigid drive line. The sine device converts the rotational motion of the motor into the reciprocating linear motion of the guide groove, thereby driving the back-and-forth tensioning of the rigid drive line.

[0008] The lead screw amplitude adjustment mechanism is fixedly connected in the grooved gear. By converting the rotation angle of the servo motor into the number of rotations of the amplitude adjustment lead screw, the distance between the amplitude adjustment nut and the center point of the grooved gear is changed, thereby changing the reciprocating distance of the guide groove to adjust the amplitude of the series-type fishtail structure.

[0009] According to this utility model, a line-driven fishtail-like device for high-frequency oscillation is provided. The series-connected fishtail-like structure includes a guide rod, a head joint, an intermediate joint, a flexible connecting column, an end joint, a flexible tail fin, and a rigid connecting ring. The guide rod is connected to the head joint, and the head joint, the intermediate joint, and the end joint are connected by the flexible connecting column. The flexible tail fin and the rigid connecting ring are integrally cast and fixed to the rigid connecting ring, and then connected to the end joint.

[0010] According to this utility model, a linearly driven fishtail-like device for high-frequency oscillation is provided. The sinusoidal device includes a grooved gear, a guide groove, a positioning groove, a hollow drive shaft, a sinusoidal device support, an angular contact ball bearing, a bearing support, a spur gear, and a drive shaft. The end face of the grooved gear is fixedly connected to the hollow drive shaft for rotation. The hollow drive shaft is fitted into the angular contact ball bearing, and the angular contact bearing is fitted into the bearing support.

[0011] The positioning groove is connected to the sine device support. The spur gear is connected to the servo motor and the grooved gear respectively. The two spur gears are connected through the transmission shaft, which is connected to the spur gear that mates with the grooved gear below the shaft support.

[0012] According to the present invention, a line-driven imitation fishtail device for high-frequency oscillation is provided. The lead screw amplitude adjustment mechanism includes an amplitude adjusting lead screw, an amplitude adjusting nut, an amplitude adjusting lead screw fixing seat, a bevel gear, and a bevel gear shaft. The bevel gear shaft is connected to a servo motor, and the bevel gear shaft is connected to the bevel gear. The bevel gear shaft is concentric with the hollow transmission shaft. The bevel gear is fixedly connected to the amplitude adjusting lead screw. The amplitude adjusting lead screw is connected to the amplitude adjusting lead screw fixing seat and fixed in the groove of the grooved gear. The amplitude adjusting lead screw cooperates with the amplitude adjusting nut.

[0013] According to the present invention, a line-driven fishtail-like device for high-frequency oscillation is characterized in that the head joint and the middle joint are both non-through holes in the vertical direction, which are the connection points of the flexible connecting column, and both are through holes in the horizontal direction, which are the passage points of the rigid drive line.

[0014] The end joint has a non-through hole in the horizontal direction, which is the connection point for the rigid drive line.

[0015] According to the present invention, a line-driven imitation fish tail device for high-frequency oscillation is characterized in that the flexible tail fin and the rigid connecting ring are integrally cast on the rigid connecting ring, and the protruding square on the rigid connecting ring is connected to the square groove on the end joint.

[0016] According to the present invention, a line-driven imitation fishtail device for high-frequency oscillation is characterized in that the radial cylindrical protrusion of the amplitude adjusting nut cooperates with the limiting cover and moves in the guide groove.

[0017] This invention provides a line-driven fishtail-simulating device for high-frequency oscillation. It utilizes the back-and-forth pulling of a rigid drive line to mimic the oscillation of a real fish tail, achieving fish-like motion. It boasts advantages such as simple structure, easy control, and high motion efficiency. The linear reciprocating mechanism converts the motor's rotational motion into linear reciprocating motion, avoiding the discontinuous motor movement caused by the forward and reverse rotation of the motor (or servo motor) in traditional line drives, which fails to fully utilize motor performance. This solves the problem of low oscillation frequency in traditional line-driven robotic fishtails, facilitating high-frequency swimming of the robotic fish. Simultaneously, the lead screw mechanism allows for online adjustment of the oscillation amplitude of the fishtail structure, promoting flexible swimming of the robotic fish. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the overall structure of the wire-driven robotic fish tail proposed in this utility model. Figure 2 This is a schematic diagram of the overall structure of the series-connected fishtail-like structure proposed in this utility model. Figure 3 This is a schematic diagram of the overall structure of the line drive mechanism proposed in this utility model; Figure 4 This is a schematic diagram illustrating the principle of maintaining the horizontal direction during tensioning motion as proposed in this utility model. Figure 5 This is a schematic diagram of the lead screw amplitude adjustment mechanism proposed in this utility model; Figure 6 This is a schematic diagram of the overall flexible tail fin proposed in this utility model.

[0019] Figure label: 1: Flexible tail fin; 2: Rigid connecting ring; 3: End joint; 4: Intermediate joint; 5: M10 screw; 6: Flexible connecting post; 7: Head joint; 8: Guide rod; 9: M5 screw; 10: M6 screw; 11: Sine device support; 12: Positioning groove; 13: Positioning groove end cap; 14: M1.6 screw; 15: Guide groove; 16: Amplitude adjusting nut; 17: Guide groove limit cap; 18: Amplitude adjusting screw; 19: Amplitude adjusting screw fixing seat; 20: Bevel gear; 21: Grooved gear; 22: Hollow drive shaft; 23: Bearing support; 24: Angular contact ball bearing; 25: Bevel gear shaft; 26: Spur gear; 27: Drive shaft; 28: Rigid drive line; 29: M3 screw. Detailed Implementation

[0020] To more clearly describe this utility model, the structure of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0021] In the description of this utility model embodiment, terms such as "up", "down", "left", "right", "front", and "back" are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0022] The following is combined with Figure 1 -- Figure 6 This invention describes a wire-driven fishtail-inspired device.

[0023] refer to Figure 1 The present invention includes: a series fishtail structure and a line drive mechanism. The series fishtail structure and the line drive mechanism are connected by a sine device support 11. The line drive mechanism outputs the reciprocating tension of the rigid drive line 28. The series fishtail structure performs a fishtail-like reciprocating swing under the drive of the rigid drive line 28.

[0024] refer to Figure 2 The series fish tail structure of this utility model includes: a flexible fish fin 1 integrally cast with flexible materials such as silicone, the flexible tail fin is fixed to a rigid connecting ring 2, and the rigid connecting ring 2 is connected to the end joint 3.

[0025] The first end joint 7 is connected to the sine device support 11, and the guide rod 8 is fixed to the end face of the first end joint 7. Its function is to guide the rigid drive line 28 to be fixed to the guide groove 15 and to keep the tension direction unchanged when the rigid drive line 28 is pulled back and forth.

[0026] The distal joint 3, intermediate joint 4, and proximal joint 7 are all connected by flexible connecting posts 6. There is a non-through circular hole on the upper and lower sides of each joint to connect the flexible connecting post 6. Except for the distal joint 3, each of the other joints has a through circular hole on both sides through which the rigid drive line 28 passes. The end of the rigid drive line 28 is fixed to the distal joint 3. The back-and-forth movement of the rigid drive line 28 causes the fish tail to make fish-like movements.

[0027] refer to Figure 3 The sine device of this utility model includes: a grooved gear 21, a hollow transmission shaft 22, an angular contact ball bearing 24, a bearing support 23, a transmission shaft 27, a spur gear 26, a guide groove 15, a positioning groove 12, and a positioning groove end cover 14 forming a sine device.

[0028] The servo motor engages with the spur gear 26 on the side of the bearing support 23 away from the fish tail. The power is transmitted to the spur gear 26, which engages with the grooved gear 21, through the transmission shaft 27 arranged below the bearing support 23, so that the grooved gear 21 rotates.

[0029] The grooved gear 21 is fixedly connected to the hollow drive shaft 22 and rotates as a whole. The hollow drive shaft 22 is fitted with the angular contact ball bearing 24. The angular contact ball bearing 24 is placed on the bearing support 23. The bearing support 23 is fixedly connected to the sine device support 11. The bearing support 23 serves to support the rotation of the grooved gear 21 and the drive shaft 27.

[0030] The amplitude adjusting nut 16 engages with the amplitude adjusting screw 18 and rotates together with the grooved gear 21. The amplitude adjusting nut 16 reciprocates up and down in the groove of the guide groove 15, parallel to the end face of the grooved gear 21, while simultaneously driving the guide groove 15 to move. Because the guide groove 15 engages with the positioning groove 12, the guide groove 15 can only reciprocate left and right along the end face of the grooved gear 21, thereby driving the two rigid drive wires 28 fixed to both sides of the guide groove 15 to perform tensioning motion.

[0031] refer to Figure 4 The schematic diagram of the principle of maintaining the horizontal direction of the tensioning motion in this utility model includes: a rectangular groove in the guide groove 15 with a rectangular protrusion at the lower end, which cooperates with the groove of the positioning groove 12 fixed on the sine device support 11 facing the groove of the groove gear 21. At the same time, the amplitude adjusting nut 16 and the guide groove limiting cover 17 move within the groove of the guide groove 15, driving the guide groove 15 to perform reciprocating linear motion. The function of the positioning groove 12 is that the horizontal direction of the rectangular groove can restrict the guide groove 15 from rotating around the amplitude adjusting nut 16 when it moves with the amplitude adjusting nut 16, so that the movement of the guide groove 15 is restricted to a horizontal left-right linear reciprocating motion.

[0032] refer to Figure 5The schematic diagram of the lead screw amplitude adjustment mechanism in this utility model includes: an amplitude adjusting lead screw 18 fixed to the grooved gear 21 via an amplitude adjusting lead screw fixing seat 19; an amplitude adjusting nut 16 cooperating with the amplitude adjusting lead screw 18; and a guide groove limiting cover 17 fixed to the amplitude adjusting nut 16, which serves to limit the excessive distance between the end face of the guide groove 15 and the end face of the grooved gear 21. The servo motor input angle is transmitted to the standard bevel gear 20 fixed to the amplitude adjusting lead screw via the bevel gear shaft 25. The angle is converted into the number of turns of the amplitude adjusting lead screw 18. The distance between the center of the amplitude adjusting nut 16 and the grooved gear 21 is controlled by the number of turns, thereby controlling the reciprocating stroke of the guide groove 15, thus controlling the back-and-forth pulling distance of the rigid drive line 28, and further controlling the amplitude of the reciprocating swing of the series-connected fishtail-like structure.

[0033] refer to Figure 6 The overall schematic diagram of the flexible tail fin in this utility model includes: an integrally cast flexible tail fin 1 and a rigid connecting ring 2, which is fixedly connected to the rigid connecting ring 2. The rigid connecting ring 2 has a cubic protrusion, which cooperates with the cubic groove of the end joint 3 to restrict rotation. There is a threaded hole in the cubic protrusion, which is connected to the end joint 3 to fix the axial movement.

[0034] The above examples are only used to illustrate the technical solution of this utility model. Although the description is detailed and specific, it is not intended to limit it. It should be noted that any modifications and variations made by those skilled in the art without departing from the concept of this utility model shall fall within the protection scope of this utility model.

Claims

1. A line-driven fishtail-like device for high-frequency oscillation, characterized in that, include: A series of fish-tail-like structures includes a bionic fish-tail structure and a rigid drive line. The bionic fish-tail structure is connected to a sine device support. The rigid drive line is connected to the bionic fish-tail structure and is fixed to both sides of a guide groove. The guide groove is used to achieve reciprocating tension of the rigid drive line by swinging to realize the swinging of the fish-tail-like structure. The linear drive mechanism includes a sine wave device and a lead screw amplitude adjustment mechanism. The sine wave device is connected to the series-connected fishtail structure. An angular contact bearing is connected to the sine wave device through a hollow transmission shaft. The guide groove is connected to the support of the sine wave device. The lead screw amplitude adjustment mechanism is connected to the grooved gear.

2. The line-driven fishtail-like device for high-frequency oscillation according to claim 1, characterized in that, The biomimetic fish tail structure includes a guide rod, a head joint, a middle joint, a flexible connecting column, an end joint, a rigid connecting ring, and a flexible tail fin. The guide rod is connected to the head joint. The head joint, the middle joint, and the end joint are connected by the flexible connecting column. The rigid connecting ring and the flexible tail fin are integrally cast and then connected to the end joint.

3. The line-driven fishtail-like device for high-frequency oscillation according to claim 1, characterized in that, The sine device includes a grooved gear, a guide groove, a positioning groove, a hollow drive shaft, a sine device support, an angular contact ball bearing, a bearing support, a spur gear, and a drive shaft. The end face of the grooved gear is fixedly connected to the hollow drive shaft and rotates as a whole. The hollow drive shaft is fitted into the angular contact ball bearing, which is fitted into the bearing support. The positioning groove is connected to the sine device support. The spur gear is respectively engaged with a servo motor and the grooved gear. The two spur gears are connected through the drive shaft, which is connected below the bearing support.

4. The line-driven fishtail-like device for high-frequency oscillation according to claim 1, characterized in that, The lead screw amplitude adjustment mechanism includes an amplitude adjusting lead screw, an amplitude adjusting nut, an amplitude adjusting lead screw fixing seat, a bevel gear, and a bevel drive shaft. One end of the bevel drive shaft is connected to the servo motor. The bevel drive shaft is concentric with the hollow drive shaft. The bevel gear is fixedly connected to one end of the amplitude adjusting lead screw. The amplitude adjusting lead screw is connected to the amplitude adjusting lead screw fixing seat and fixed in the groove of the groove gear. The amplitude adjusting lead screw cooperates with the amplitude adjusting nut.

5. A line-driven fishtail-like device for high-frequency oscillation according to claim 2, characterized in that, Both the first joint and the intermediate joint have non-through holes in the vertical direction, which are the connection points of the flexible connecting columns. In the horizontal direction, they are both through holes, which are the passage points of the rigid drive lines. The last joint has non-through holes in the horizontal direction, which are the fixed points of the rigid drive lines.

6. A line-driven fishtail-like device for high-frequency oscillation according to claim 2, characterized in that, The flexible tail fin and the rigid connecting ring are integrally cast onto the rigid connecting ring, and the protruding square on the rigid connecting ring is connected to the square groove on the end joint.

7. A line-driven fishtail-like device for high-frequency oscillation according to claim 3, characterized in that, The grooved gear has a rectangular groove on its end face and a through hole at the center.

8. A line-driven fishtail-like device for high-frequency oscillation according to claim 3, characterized in that, The guide groove has a rectangular protrusion perpendicular to the end face at its lower end, which mates with the rectangular groove of the positioning groove, and the end face of the positioning groove is connected to the end face of the positioning groove.

9. A line-driven fishtail-like device for high-frequency oscillation according to claim 4, characterized in that, The radial cylindrical protrusion of the amplitude adjusting nut engages with the guide groove limiting cover and moves within the guide groove.

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