CN104875868A - Robotic fish based on dual-bevel deflection joint - Google Patents

Abstract

The invention provides a robot fish based on a double-slope deflection joint, which includes a fish head, a fish body and a fish tail. The fish head and fish body are scanned by 3D to scan the actual fish, and the CAD model is modified to make molds. The fish head is equipped with a circuit board, a lithium battery or a nickel-metal hydride battery, an infrared ranging sensor, a miniature gyroscope, a GPS navigation module, and the like. Described fish body is made of ABS plastics, PVC material, aluminum alloy material, nylon material or rubber material etc., and internal support structure (support ring and support plate) and counterweight are arranged. The fishtail is driven by a double-slope deflection joint, and the joint is wrapped with a bellows, and the bellows is fixed at the fishtail and the fish body by a snap ring for waterproof sealing. The fishtail is fixed on the proximal base. The present invention is based on double-slope deflection joints, has fast swing propulsion characteristics and good diving characteristics, and is easy to control the motion parameters of the caudal fin.

Description

A robotic fish based on double-slope deflection joints

technical field

The invention relates to the technical field of automation and robotics, in particular to the technical field of bionic propulsion mechanisms for underwater robots, and in particular to a robotic fish based on double-slope deflection joints.

Background technique

Thanks to trillions of years of evolution, fish have an extraordinary ability to move in water. Compared with conventional underwater propellers using propeller or impeller principles, fish sports have the advantages of high propulsion efficiency, low environmental noise, and small turning radius. It provides a good idea for developing underwater thrusters with high efficiency, low noise and good maneuverability. At present, it is an important research direction of underwater robots to imitate the shape and swimming mechanism of fish, design and manufacture a bionic robotic fish system with high performance, and make it applicable to resource detection and military reconnaissance in complex environments.

At present, the propulsion mechanism of most bionic robotic fish adopts a motor-driven multi-joint cascading method. In order to realize the swing of the robotic fish tail, the motor needs to change directions frequently, and it is difficult to use the high-speed motion characteristics of the motor, and the waterproof problem of the propulsion mechanism is also restricted. The performance improvement and wide application of robotic fish are achieved.

There are three main methods of ups and downs commonly used by robotic fish: adjusting the displacement by changing its own volume, adjusting the center of gravity by adjusting the pitch angle of the fish head, and adjusting the pectoral fin by adjusting the direction of the pectoral fin. The displacement adjustment method needs a cylinder and needs to be connected with water, which causes a large volume on the one hand and makes sealing difficult on the other hand. The center of gravity adjustment method is cumbersome to adjust the counterweight, especially when the load is uncertain. In the pectoral fin adjustment method, the thrust produced by the pectoral fin is limited, and the complexity and cost of the mechanism are increased.

Contents of the invention

The purpose of the present invention is to provide a robotic fish based on a double-slope deflection joint, which drives the fish tail of the robotic fish through a double-slope deflection joint. The high-frequency swing can realize the fast swimming of the robotic fish. At the same time, the rise, dive and turn of the robotic fish can be realized by adjusting the direction of the fish tail. In addition, the bellows are directly wrapped around the double-slope deflection joint, which can achieve good sealing performance. The invention realizes the high-frequency swing of the fish tail by means of the dual motor differential, and realizes the basic functions of the bionic robot fish such as advancing, turning, ups and downs, etc. by adjusting the posture direction of the fish tail, and provides a feasible solution for realizing the rapid movement of the bionic robot fish plan.

The technical solution adopted in the present invention is: a robotic fish based on double-slope deflection joints, which includes a fish head, a fish body, and a fish tail. After the CAD model is modified, the mold is made. The fish head is equipped with a circuit board, a lithium battery or a nickel-metal hydride battery, an infrared ranging sensor, a miniature gyroscope and a GPS navigation module. The circuit board is used to control the behavior mode of the robotic fish, providing The interface of the infrared ranging sensor, miniature gyroscope and GPS navigation module guides the movement of the robot fish in the water by analyzing the collected sensing signals or remote control signals. Lithium batteries or nickel-metal hydride batteries are used for the power supply of the robot fish, including circuits Board, motor, infrared ranging sensor, miniature gyroscope, power supply for GPS navigation module. The infrared ranging sensor is used for environmental perception when the robotic fish cruises autonomously, so that the robotic fish can work safely and autonomously underwater. The miniature gyroscope It is used to obtain the posture of the robot fish when it is cruising, so that the robot fish can work smoothly underwater; the GPS navigation module is used for the positioning of the robot fish, providing the basis for the autonomous navigation of the robot, and the circuit board is fixed by the support plate in the fish head. Lithium battery or Ni-MH battery is connected to the circuit board and fixed on the support plate, placed under the fish head, and the infrared ranging sensor is connected to the circuit board and fixed on the support plate, placed in front of the fish head; miniature gyroscope and GPS After the navigation module is connected with the circuit board, it is fixed on the rear of the fish head; the fish body is made of ABS plastic, PVC material, aluminum alloy material, nylon material or rubber material, and there are support structures and counterweights inside the fish body. The fishtail is driven by a double-slope deflection joint, which is wrapped with a bellows, and the bellows is fixed at the fishtail and fish body by a snap ring for waterproof sealing, and the fishtail is fixed at the proximal base of the double-slope deflection joint superior.

Further, the double-slope deflection joint includes a proximal servo motor, a proximal base, a first tapered roller bearing, a proximal coupling, a proximal universal joint yoke, a proximal harmonic reducer, and a proximal bushing , near-end inclined-plane turning block, second tapered roller bearing, flange, cross shaft, third tapered roller bearing, fourth tapered roller bearing, far-end inclined-plane turning block, far-end bushing, far-end harmonic deceleration device, distal universal joint yoke, distal coupling, fifth tapered roller bearing, distal base and distal servo motor. The proximal servo motor is installed on the proximal base, the proximal universal joint fork is consolidated with the proximal base, and the proximal servo motor is connected with the wave generator at the input end of the proximal harmonic reducer through a proximal coupling. The output end of the near-end harmonic reducer is connected with the near-end inclined-plane turning block. The remote servo motor is installed on the remote base, the remote universal joint fork is consolidated with the remote base, and the remote coupling is connected with the wave generator at the input end of the remote harmonic reducer. The output end of the far-end harmonic reducer is connected with the far-end inclined-plane turning block. The proximal universal joint fork is connected with the distal universal joint fork through a cross shaft to form a universal joint. The proximal inclined-plane turning block is connected with the distal inclined-plane turning block through a flange equipped with a third tapered roller bearing to realize mutual rotation on the inclined end surfaces.

Further, when working, the initial position of the fishtail can be adjusted through the proximal servo motor, so that the position of the center line of the fishtail is either horizontal or at a certain angle. When the proximal and distal servo motors rotate at a differential speed, the fishtail realizes two-way Swinging back and forth, the robotic fish can either move forward quickly, or ascend and dive; when only the proximal servo motor rotates, the robotic fish can turn left or right.

Further, the caudal fin joint of the fish body is wrapped with bellows, which has a waterproof function.

Further, the circuit board includes a microcontroller, a communication module, a power detection module and a navigation module; the microcontroller precisely controls the near-end servo motor and the remote servo motor through the interpolation mode, and the microcontroller uses the communication module to pass The wireless communication mode communicates with the upper computer, and the microcontroller realizes the autonomous movement of the robotic fish through the navigation module.

Advantage and positive effect of the present invention are:

The robotic fish propulsion mechanism of the present invention is based on double-slope deflection joints, has fast swing propulsion characteristics and good diving characteristics, and is easy to control the motion parameters of the tail fin. Concrete advantage of the present invention shows in the following aspects:

First, based on the double-slope deflection joints, the robot fish can realize basic functions such as forward, floating and turning, and the motor does not need to change direction frequently when moving forward, so it can realize the fast swinging propulsion of the fish tail;

Second, the double-slope deflection joint adopts a servo motor, which is easy to realize precise adjustment of motion parameters;

Third, by wrapping the deflection joints with bellows, the robot fish can achieve a good sealing effect.

The invention can be applied to occasions such as water quality monitoring, resource detection and military reconnaissance.

Description of drawings

Fig. 1 is the outline drawing of the robotic fish with double-slope deflection joints of the present invention;

Fig. 2 is a schematic diagram of the rise of the robot fish with double inclined plane deflection joints of the present invention;

Fig. 3 is a schematic diagram of a diving robot fish with double inclined plane deflection joints of the present invention;

Fig. 4 is the internal structure diagram of the double-slope deflection joint of the present invention, wherein Fig. 4a and Fig. 4b are the front view and top view of the internal structure diagram of the double-slope deflection joint respectively;

Fig. 5 is a schematic diagram of the movement of the double-slope deflection joint of the present invention;

Fig. 6 is an outline view of another embodiment of the double-slope deflection joint robotic fish of the present invention.

Explanation of symbols in the figure: 1. Fish tail, 2. Bellows, 3. Double-slope deflection joint, 4. Snap ring, 5. Fish body, 6. Circuit board, 7. Battery, 8. Infrared distance measuring sensor, 9. Fish head, 10, support structure, 11, miniature gyroscope and GPS navigation module, 12, proximal servo motor, 13, proximal base, 14, first tapered roller bearing, 15, proximal coupling, 16, Proximal universal joint yoke, 17, proximal harmonic reducer, 18, proximal shaft sleeve, 19, proximal bevel turning block, 20, second tapered roller bearing, 21, flange, 22, cross shaft, 23. The third tapered roller bearing, 24. The far-end inclined-plane turning block, 25. The far-end harmonic reducer, 26. The far-end universal joint fork, 27. The far-end base, 28. The far-end servo motor, 29. Fourth tapered roller bearing, 30, distal shaft sleeve, 31, distal coupling, 32, fifth tapered roller bearing, 33, tail distal flange, 34, tail bearing, 35, tail proximal method Lan, 36, tail motor, 37, tail connector.

Detailed ways

The present invention will be further described below with reference to the accompanying drawings and examples.

As shown in FIGS. 1 to 3 , the robot fish based on the double-slope deflection joint includes a fish head 9 , a fish body 5 and a fish tail 1 . Described fish head contains circuit board 6, battery 7 and infrared ranging sensor 8 etc. The infrared ranging sensor can also be replaced by an ultrasonic ranging sensor, a visual sensor, and the like. The fish head and the fish body are manufactured by 3D scanning the actual fish and then making a mold. The shape of the fish head and the fish body can be replaced by other shapes, such as cylinder shape, torpedo shape, etc. The inside of the fish body is supported by a supporting structure 10, and a plurality of double-slope deflection joints 3 can be added. The fish tail and the fish body are sealed by wrapping the bellows 2, and the bellows are fixed on the ends of the fish tail and the fish body by a snap ring 4. The shape of the fishtail can be crescent-shaped or fan-shaped, and can be replaced by a combination of 1 piece, 2 pieces or a combination of multiple pieces.

As shown in Figure 4, the double-slope deflection joint 3 is composed of two centrally symmetrical driving parts, and is driven by a universal joint. The specific movement method is as follows: the proximal servo motor 12 is fixed on the proximal base 13 , the output shaft of the proximal servo motor 12 is connected to the proximal coupling 15, the other end of the proximal coupling 15 is connected to the proximal harmonic reducer 17, and the output end of the proximal harmonic reducer 17 is connected to the proximal harmonic reducer 17. The end inclined-plane turning block 19 links to each other. The remote servo motor 28 is fixed on the remote base 27, the output shaft of the remote servo motor 28 is connected to the remote coupling 31, and the other end of the remote coupling 31 is connected to the remote harmonic reducer 25, The output end of the far-end harmonic reducer 25 is connected with the far-end inclined plane turning block 24 . The proximal base is consolidated with the proximal universal joint fork, and the distal base is consolidated with the distal universal joint fork. The proximal universal joint fork 16, the distal universal joint fork 26 and the cross shaft 22 form a universal joint . The near-end inclined-plane turning block 19 is connected to the distal-end inclined-plane turning block 24 through a flange 21, and mutual rotation on an inclined plane is realized between them.

The harmonic reducer can be replaced by a gear reducer, a worm reducer, a planetary gear reducer, an RV reducer, or directly driven by a motor without a reducer.

The universal joint composed of the universal joint fork and the cross shaft can be placed outside or inside the inclined plane turning block, and can be replaced by other universal joints or ball hinges.

As shown in Figure 5, the double-slope deflection joint can be simplified as a universal joint constraint, and it can be seen from the figure that the movement space of the end point is a spherical cap. When the two driving motors of the joint rotate at a differential speed, the trajectory of the end point is a circular arc, and the extreme position is shown by the double-dot dash line in the figure. In this case, the motor can run at the rated power to realize the rapid advance of the robotic fish. In addition, in the motion space, the two drive motors of the joints can track parameterized trajectories, which in turn enables the robotic fish to achieve other special forward methods.

The propulsion method of the robotic fish can be swing propulsion, flap propulsion or helical propulsion.

As shown in Figure 6, the tail of the robotic fish has one more degree of freedom than the tail of the robotic fish shown in Figures 1 to 3, and can achieve 360-degree rotation. The shown tail is connected to the proximal base 13 by a tail connection 37, thereby connecting at the end of the ramp joint. The tail is directly driven by a motor 36 . The tail realizes the relative rotation with the tail connecting piece 37 through the tail bearing 34 . Both sides of the tail bearing 34 are also axially fixed with a tail proximal flange 35 and a tail distal flange 33. In addition, the tail can also be driven by pneumatic or hydraulic pressure, and a transmission mechanism (such as gears, pulleys, connecting rods, etc.) is added in the middle. The robotic fish can not only realize the above-mentioned propulsion method, but also can realize vector propulsion.

The above-mentioned embodiments are only preferred embodiments of the present invention, and do not constitute a limitation to the scope of the present application. For those skilled in the art of the present invention, the present invention may also have some modifications or improvements. Any equivalent replacements, modifications, improvements, etc. made without departing from the concept and principle of the present invention shall fall within the protection scope of the present invention.

Claims (5)

1. A robotic fish based on double-slope deflection joints, which includes a fish head, a fish body, and a fish tail, and is characterized in that, the fish head and the fish body part scan the actual fish through 3D, and the CAD model is modified to open Mold making, the fish head is equipped with a circuit board, lithium battery or nickel-metal hydride battery, infrared ranging sensor, miniature gyroscope and GPS navigation module, the circuit board is used to control the behavior mode of the robot fish, providing infrared ranging sensor, miniature The interface between the gyroscope and the GPS navigation module guides the movement of the robotic fish in the water by analyzing the collected sensing signals or remote control signals. Lithium batteries or Ni-MH batteries are used for the power supply of the robotic fish, including circuit boards, motors, and infrared sensors. The distance sensor, miniature gyroscope, power supply for GPS navigation module, the infrared ranging sensor is used for the environment perception when the robot fish autonomously cruises, so that the robot fish can work safely and autonomously underwater, and the miniature gyroscope is used to obtain the robot fish cruise The posture of the robot fish can work smoothly underwater; the GPS navigation module is used for the positioning of the robot fish and provides the basis for the autonomous navigation of the robot. The circuit board is fixed by the support plate in the fish head, and the lithium battery or NiMH After being connected with the circuit board, it is fixed on the support plate and placed under the fish head. After the infrared distance measuring sensor is connected with the circuit board, it is fixed on the support plate and placed in front of the fish head; the miniature gyroscope and GPS navigation module are connected to the circuit board. After connection, it is fixed at the rear of the fish head; the fish body is made of ABS plastic, PVC material, aluminum alloy material, nylon material or rubber material, and there are supporting structures and counterweights inside the fish body; the fish tail is formed by a double slope The deflection joint is driven, and the joint is wrapped with a bellows. The bellows is fixed on the fishtail and the fish body by a snap ring for waterproof sealing. The fishtail is fixed on the proximal base of the double-slope deflection joint. 2. A robotic fish based on a double-slope deflection joint according to claim 1, wherein the double-slope deflection joint comprises a proximal servo motor, a proximal base, a first tapered roller bearing, a proximal coupling Shaft device, proximal universal joint yoke, proximal harmonic reducer, proximal shaft sleeve, proximal bevel turn block, second tapered roller bearing, flange, cross shaft, third tapered roller bearing, fourth Tapered Roller Bearing, Distal Slope Turn Block, Distal Bushing, Distal Harmonic Reducer, Distal Universal Joint Fork, Distal Coupling, Fifth Tapered Roller Bearing, Distal Base, and Distal Servo Motor; the proximal servo motor is installed on the proximal base, the proximal universal joint fork is consolidated with the proximal base, and the proximal servo motor enters the wave generator through the proximal coupling and the proximal harmonic reducer connected; the output end of the near-end harmonic reducer is connected to the near-end inclined-plane rotary block; the far-end servo motor is installed on the far-end base, the far-end universal joint fork is consolidated with the far-end base, and the far-end coupling It is connected with the wave generator at the input end of the far-end harmonic reducer; the output end of the far-end harmonic reducer is connected with the far-end inclined-plane turning block; the near-end universal joint fork and the far-end universal joint fork pass The shafts are connected to form a universal joint; the near-end inclined-plane turning block and the distal-end inclined-plane turning block are connected through a flange equipped with a third tapered roller bearing to realize mutual rotation on the inclined end faces. 3. A robotic fish based on double-slope deflection joints according to claim 2, characterized in that, when the robotic fish is working, the initial position of the fish tail can be adjusted by the proximal servo motor, so that the position of the center line of the fish tail Either horizontally or at a certain angle, when the proximal and distal servo motors rotate at a differential speed, the fish tail realizes two-way reciprocating swing, and the robotic fish can either move forward rapidly, or rise and dive; when only the proximal servo motor rotates, the machine Fish can turn left or right. 4. A robotic fish based on double-slope deflection joints according to claim 2, characterized in that the caudal fin joints of the fish body are wrapped with bellows, which has a waterproof function. 5. A kind of robotic fish based on double-slope deflection joints according to claim 2, wherein the circuit board includes a microcontroller, a communication module, a power detection module and a navigation module; The proximal servo motor and the remote servo motor are precisely controlled. The microcontroller uses the communication module to communicate with the upper computer through wireless communication. The microcontroller realizes the autonomous movement of the robotic fish through the navigation module.