CN114212229B

CN114212229B - Deformable fish fin based on memory metal control

Info

Publication number: CN114212229B
Application number: CN202111623531.2A
Authority: CN
Inventors: 萧仲敏; 胡献; 叶冠伟; 唐睿智
Original assignee: Guangzhou University
Current assignee: Guangzhou University
Priority date: 2021-12-28
Filing date: 2021-12-28
Publication date: 2023-03-21
Anticipated expiration: 2041-12-28
Also published as: CN114212229A

Abstract

The invention provides a deformable fin based on memory metal control, which comprises a memory metal spring, a soft fin and a fin fixing frame, wherein the fin fixing frame is fixedly connected with a robot fish body, the soft fin is hinged with the fin fixing frame, and one end of the soft fin is hinged with the end head part of the memory metal spring. The memory metal spring drives the soft fins to rotate on the fin fixing frame, so that the resistance of the robot fish during accelerated advancing can be reduced, the robot fish is helped to reduce energy consumption, various swimming behaviors of the fish are adapted, the effect of linear motion is achieved, and corresponding energy consumption is reduced.

Description

Deformable fish fin based on memory metal control

Technical Field

The invention relates to the technical field of soft robotic fish, in particular to a deformable fish fin based on memory metal control.

Background

In the underwater swimming process of the robot fish, the robot fish can be subjected to larger resistance when being accelerated due to the resistance of water, the acceleration effect is influenced, and the problem of energy consumption generated by the robot fish is not negligible. Most robotic fish typically utilize increased flapping intensity to the tail fin to increase the propulsion of the water to the fish in terms of forward acceleration. But the strengthening mode undoubtedly enables the energy consumption of the robot fish under water to be further improved, and indirectly reduces the cruising ability of the robot fish under water.

Disclosure of Invention

The invention aims to provide a deformable fish fin based on memory metal control, which can reduce resistance when a robotic fish advances in an accelerating way so as to help the robotic fish reduce energy consumption.

According to an object of the invention, the deformable fin based on memory metal control comprises a memory metal spring, a soft fin and a fin fixing frame, wherein the fin fixing frame is fixedly connected with a machine fish body, the soft fin is hinged with the fin fixing frame, and one end of the soft fin is hinged with the end head part of the memory metal spring.

Furthermore, the soft fin comprises a power fin and at least one combined control fin, at least one combined control fin is arranged behind the power fin, one end of the power fin and one end of the combined control fin are respectively hinged with the fin fixing frame, and the other end of the power fin and the other end of the combined control fin are respectively hinged with the fin connecting support.

Further, the power fins include first fins, the joint control fins include second fins, third fins and fourth fins, the first fins are mounted foremost, the second fins are mounted behind the first fins, the third fins are mounted behind the second fins, and the fourth fins are mounted rearmost.

Further, in an initial state, the soft fins form an included angle of 90 degrees with the water surface.

Further, the memory metal spring exists in two states: the spring is in an extended state when not heated, and becomes a spring state according to the characteristics of the memory metal after heating.

The soft actuator comprises a first actuator fixing frame, a second actuator fixing frame and a soft actuating device, the first actuator fixing frame is installed at the assembling position of the fin fixing frame and the soft fin, the second actuator fixing frame is installed at the assembling position of the fin connecting support and the soft fin, and two ends of the soft actuating device are fixedly connected with the first actuator fixing frame and the second actuator fixing frame respectively.

Further, the soft actuating devices are symmetrically arranged on two sides of the soft fish fin respectively.

Further, the soft actuating device is of a cylindrical structure.

Further, after the deformation is completed, the memory metal spring is stretched under the action of the driving device and becomes a linear state.

Further, the driving device comprises a motor, a gear and a rack, the gear is connected with an output shaft of the motor, the rack is meshed with the gear, and the memory metal spring is connected with the rack.

According to the technical scheme, the memory metal spring drives the soft fish fins to rotate on the fish fin fixing frame, so that the resistance of the robot fish in the process of accelerating to advance can be reduced, and the energy consumption of the robot fish is reduced.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and other drawings can be obtained by those skilled in the art without creative efforts.

FIG. 1 is a general view of a deformable fin according to an embodiment of the present invention after heating and recovery of memory metal.

Fig. 2 is a schematic diagram illustrating an initial state of a deformable fin in a normal state after stretching according to an embodiment of the present invention.

FIG. 3 is a schematic diagram of the overall structure of a deformable fin according to an embodiment of the invention;

in the figure, 1, a memory metal spring; 2. a fin fixing frame; 3. the fin is connected with the bracket; 4. a first fin; 5. a second fin; 6. a third fin; 7. a fourth fin; 8. a soft actuator; 9. a first actuator mount; 10. a second actuator mount; 11. a soft actuating device.

Detailed Description

The technical solutions of the present invention will be described clearly and completely with reference to the following embodiments, and it should be understood that the described embodiments are some, but not all, embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

In the description of the present invention, it is to be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", and the like, indicate orientations and positional relationships based on those shown in the drawings, and are used only for convenience of description and simplicity of description, and do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be considered as limiting the present invention.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, features defined as "first", "second", may explicitly or implicitly include one or more of the described features. In the description of the present invention, "a plurality" means two or more unless specifically defined otherwise. Furthermore, the terms "mounted," "connected," and "connected" are to be construed broadly and may, for example, be fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.

Example 1

As shown in fig. 1-3:

a deformable fish fin based on memory metal control comprises a memory metal spring 1, a soft fish fin and a fish fin fixing frame 2, wherein the fish fin fixing frame 2 is fixedly connected with a machine fish body. The soft fins are hinged with the fin fixing frame 2, and the fin fixing frame 2 ensures the relative positions of the soft fins and the machine fish and fixes the soft fins on the machine fish.

One end of the soft fish fin is hinged with the end part of the memory metal spring 1. The memory metal spring 1 exists in two states: the spring is in an extended state when not heated, and is changed into a spring state by the characteristics of the memory metal after being heated. In the initial state, the soft fins form an included angle of 90 degrees with the water surface. The metal characteristic that this embodiment utilized, like common ferronickel memory metal, becomes the spring state when heating to certain temperature, controls the fin.

The soft fins are driven by the memory metal spring 1 to rotate. The memory metal spring is stretched under the action of the driving device and becomes a linear state. The driving device comprises a motor, a gear and a rack, the gear is connected with an output shaft of the motor, the rack is meshed with the gear, and the memory metal spring is connected with the rack. After the deformation is completed, the memory metal spring 1 is stretched under the action of the rack and becomes a linear state.

The soft fin comprises a power fin and at least one combined control fin, the at least one combined control fin is arranged behind the power fin, one end of the power fin and one end of the combined control fin are hinged to the fin fixing frame 2 respectively, and the other ends of the power fin and the combined control fin are hinged to the fin connecting support 3 respectively.

The power fin includes first fin 4, and the joint control fin includes second fin 5, third fin 6 and fourth fin 7, and first fin 4 is installed at foremost, and second fin 5 is installed in the rear of first fin 4, and third fin 6 is installed in the rear of second fin 5, and fourth fin 7 is installed at rearmost, and two fins, third fin and fourth fin can be used to the joint control fin.

The memory metal spring 1 is restored to be in a spring shape by heating the memory metal spring 1, and the first fin 4 is rotated by a certain angle; when the first fin 4 rotates, the second fin 5, the third fin 6 and the fourth fin 7 are driven to rotate simultaneously through the fin connecting support 3, and deformation of the soft fins is achieved. After the deformation is completed, when the normal state is recovered, the memory metal spring 1 is stretched under the action of external force and becomes a linear state. The first fin 4 rotates and restores to the initial state (90 degrees with the water surface), and the first fin 4 drives the second fin 5, the third fin 6 and the fourth fin 7 to rotate simultaneously through the fin connecting support 3, so that the soft fin is restored.

The soft actuator 8 comprises a first actuator fixing frame 9, a second actuator fixing frame 10 and a soft actuating device 11, the first actuator fixing frame 9 is installed at the assembling position of the fin fixing frame 2 and the soft fin, the second actuator fixing frame 10 is installed at the assembling position of the fin connecting support 2 and the soft fin, and two ends of the soft actuating device 11 are fixedly connected with the first actuator fixing frame 9 and the second actuator fixing frame 10 respectively. The orientation of the soft actuator 11 may change as the orientation of the soft fins changes.

The soft actuating devices 11 are respectively and symmetrically arranged at two sides of the soft fish fin, and the soft actuating devices 11 are of cylindrical structures. When lateral force is applied, the soft fish fins are buffered by using two cylindrical soft actuating devices 11 which are symmetrically arranged at the left side and the right side, and the yawing capability of the soft fish fins is reduced. When not subjected to lateral forces from the water stream, the fins are upright, in which case the side areas of the fish are relatively large. When the lateral force of water flow is applied, the fins are deflected to the corresponding direction, the stress area of the fins is reduced, and the stress is reduced, so that the fins are buffered, the overall stress of the fish is reduced, and the yaw is reduced.

According to the invention, the memory metal spring 1 drives the soft fins to rotate on the fin fixing frame 2, so that the resistance of the robot fish in the process of accelerating to advance can be reduced, the robot fish is helped to reduce the energy consumption, various swimming behaviors of the fish are adapted, the effect of linear motion is achieved, and the corresponding energy consumption is reduced. The soft actuators 8 reduce the robotic fish's influence from lateral forces, reducing its yaw capacity.

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solution of the present invention, and not to limit the same; while the invention has been described in detail and with reference to the foregoing embodiments, it will be understood by those skilled in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some or all of the technical features may be equivalently replaced; and the modifications or the substitutions do not make the essence of the corresponding technical solutions depart from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A deformable fish fin based on memory metal control is characterized by comprising a memory metal spring, a soft fish fin and a fish fin fixing frame, wherein the fish fin fixing frame is fixedly connected with a robot fish body, the soft fish fin is hinged with the fish fin fixing frame, and one end of the soft fish fin is hinged with the end head part of the memory metal spring; the soft fins comprise a power fin and at least one combined control fin, the at least one combined control fin is arranged behind the power fin, one end of the power fin and one end of the combined control fin are respectively hinged with the fin fixing frame, and the other end of the power fin and the other end of the combined control fin are respectively hinged with the fin connecting support; the memory metal spring has two states: the spring is in an extension state when not heated, and is changed into a spring state according to the characteristics of the memory metal after being heated; the soft actuator comprises a first actuator fixing frame, a second actuator fixing frame and a soft actuating device, the first actuator fixing frame is installed at the assembling position of the fin fixing frame and the soft fin, the second actuator fixing frame is installed at the assembling position of the fin connecting support and the soft fin, and two ends of the soft actuating device are fixedly connected with the first actuator fixing frame and the second actuator fixing frame respectively.

2. A deformable fin according to claim 1, wherein said powered fin comprises a first fin, and said joint control fin comprises a second fin, a third fin and a fourth fin, said first fin being mounted foremost, said second fin being mounted behind said first fin, said third fin being mounted behind said second fin, and said fourth fin being mounted rearmost.

3. A deformable fin according to claim 1, wherein the soft fin is at a 90 degree angle to the water surface in the initial state.

4. A deformable fin according to claim 1, wherein said soft actuators are symmetrically mounted on either side of said soft fin.

5. A deformable fin according to claim 4, where said soft actuator is of cylindrical configuration.

6. A deformable fin according to claim 1, wherein the memory metal spring is stretched by the driving means to a straight shape after the deformation is completed.

7. A deformable fin as claimed in claim 6, wherein said drive means includes a motor, a gear connected to an output shaft of said motor, and a rack engaged with said gear, said memory metal spring being connected to said rack.