Bionic robotic fish with tail fin and propeller integrated deformation dual-mode propulsion

Abstract

The application discloses a bionic robotic fish with tail fin and propeller integrated deformation dual-mode propulsion, and belongs to the underwater robot field, comprising a head module, a tail swing driving module and a tail fin deformation propulsion module. The head module constitutes the head shape of a bionic fish, and is internally provided with a sensing module, a main control module and a power supply module; the sensing module collects body posture information, the main control module generates a control signal, and the power supply module is used for power supply. The tail swing driving module drives the fish tail swing propulsion in the tail fin mode, and adjusts the tail posture in the propeller mode. The tail fin deformation propulsion module drives the tail fin deformation propulsion module as a whole to rotate while driving the tail fin blade deformation through the same brushless driving motor, so that the propulsion between the tail fin mode and the propeller mode is switched. The application can keep strong bionics and concealment in the tail fin mode, realize fast maneuvering in the propeller mode, and improve the adaptive capacity of the bionic robotic fish to different task stages and different underwater environments.

Description

Technical Field

[0001] This invention belongs to the field of underwater robots, specifically relating to a biomimetic robotic fish with a dual-mode propulsion system that combines a tail fin and a propeller in a single deformable form. Background Technology

[0002] Bionic robotic fish are underwater robots that can mimic the shape and swimming style of fish. They are widely used in underwater environmental monitoring, target approach, sample acquisition, and operations in complex waters. They can replace or assist humans in entering dangerous or inaccessible underwater environments to perform tasks, and have high environmental adaptability and operational flexibility.

[0003] Most existing biomimetic robotic fish employ a single propulsion method. Some rely primarily on tail fin movements for propulsion, offering good biomimicry and stealth capabilities, but their propulsion is limited when rapid maneuvering or relocation is required. Other underwater robots enhance maneuverability by adding propeller mechanisms to the exterior of the fish body; however, these additional propeller mechanisms often disrupt the original shape of the biomimetic robotic fish, increasing exposed components and affecting its stealth and biomimetic effect when approaching a target.

[0004] In addition, existing deformable propulsion schemes usually require additional dedicated switching mechanisms when switching between different propulsion modes, which increases the complexity of the mechanism, makes the system layout more cumbersome, and is not conducive to integration in the limited tail space.

[0005] Therefore, it is necessary to propose a biomimetic robotic fish with a dual-mode propulsion system that integrates a tail fin and a propeller. This biomimetic robotic fish can switch between tail fin mode and propeller mode using the same tail end structure, and uses only a single brushless drive motor to achieve both mode switching and propeller rotation. There is no need to set up an additional dedicated power source for mode switching. Thus, while maintaining the stealth and biomimetic properties in tail fin mode, it also takes into account the rapid maneuverability and tail integration in propeller mode, thereby improving the adaptability and execution capabilities of the biomimetic robotic fish in different mission stages and different underwater environments. Summary of the Invention

[0006] To address the problems in the prior art, this invention proposes a biomimetic robotic fish with a dual-mode propulsion system that combines a tail fin and a propeller. By designing the tail propulsion end as a deformable structure that can switch between tail fin and propeller modes, the biomimetic robotic fish maintains its biomimetic shape while possessing dual-mode propulsion capabilities.

[0007] This invention discloses a biomimetic robotic fish with a dual-mode propulsion system that integrates a tail fin and a propeller. The biomimetic robotic fish includes a head module, a tail-wagging drive module, and a tail fin deformation propulsion module connected in sequence.

[0008] The head module forms the shape of a biomimetic robotic fish head, and electronic components are installed inside the head module.

[0009] The tail-wagging drive module includes a multi-section chain-connected tail-wagging joint, which is used to form the shape of the middle section of the biomimetic robotic fish, and drives the tail fin to sway by swinging left and right through the tail-wagging joint.

[0010] The tail fin deformation propulsion module constitutes the tail structure of the biomimetic robotic fish, used to achieve dual-mode propulsion of tail fin mode and propeller mode; the tail fin deformation propulsion module includes a first tail fin blade integrated component, a second tail fin blade integrated component, and a tail fin drive system; both the first and second tail fin blade integrated components are semi-tail fin shaped blades, and the roots of both the first and second tail fin blade integrated components are connected to the tail fin drive system, which is connected to the rear end of the tail swing drive module;

[0011] In the caudal fin mode, there is no included angle between the first caudal fin blade integrated component and the second caudal fin blade integrated component, together forming a complete caudal fin shape.

[0012] In propeller mode, the first tail fin blade assembly and the second tail fin blade assembly rotate in opposite directions around their respective roots to a predetermined angle under the drive of the tail fin drive system, together forming a double-bladed propeller structure; the tail fin deformation propulsion module rotates around the axis of the double-bladed propeller under the drive of the tail fin drive system, providing propulsion power for the biomimetic robotic fish to swim.

[0013] This invention also provides a method for the same-body dual-mode propulsion of a biomimetic robotic fish based on the aforementioned dual-mode propulsion of the tail fin and propeller deforming together, comprising:

[0014] When the tail fin deformation propulsion module switches from tail fin mode to propeller mode, the brushless drive motor rotates forward, driving the first tail fin blade assembly and the second tail fin blade assembly to rotate to a preset angle through the bevel gear transmission system, forming a double-bladed propeller structure. Subsequently, the first tail fin blade assembly and the second tail fin blade assembly stabilize at their current positions under the continuous drive of the brushless drive motor, thus maintaining a stable double-bladed propeller structure. The mating irregular-shaped tube rotates under the continuous drive of the brushless drive motor, driving the tail fin deformation propulsion module to rotate as a whole, realizing propeller propulsion.

[0015] When the tail fin deformation propulsion module switches from propeller mode to tail fin mode, the brushless drive motor reverses, causing the entire tail fin deformation propulsion module to stop rotating. Then, through the bevel gear transmission system, it drives the first tail fin blade assembly and the second tail fin blade assembly to rotate to a point without angle, restoring the complete tail fin shape. The brushless drive motor then stops rotating. Subsequently, the tail swing drive module drives the tail fin deformation propulsion module to swing and achieve propulsion.

[0016] Compared with the prior art, the present invention has the following beneficial effects:

[0017] (1) Compared with existing bionic robotic fish that use a single tail fin propulsion method, the present invention realizes two propulsion modes, tail fin mode and propeller mode, on the same tail end structure, so that the bionic robotic fish can switch between different propulsion modes according to different task stages.

[0018] (2) Compared with an external independent propeller propulsion mechanism, the present invention still maintains the biomimetic tail fin shape in the tail fin mode, which has better biomimeticity and concealment, and is more suitable for approaching the target or performing tasks that require weak interference.

[0019] (3) Compared with the deformation propulsion scheme that requires additional configuration of mode switching actuator, the present invention uses the same brushless drive motor to realize both mode switching drive and propeller mode rotation propulsion. There is no need to set up a special mode switching power source, which is conducive to simplifying the structure and improving the utilization rate of tail end space.

[0020] (4) Compared with the single bionic tail-wagging propulsion scheme, the present invention has a stronger rapid maneuverability in the propeller mode; therefore, the present invention can take into account both the bionic approach characteristics of the tail fin mode and the rapid maneuverability of the propeller mode, and improve the adaptability and execution capability of the bionic robotic fish under different underwater working conditions. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the overall structure of an embodiment of this application;

[0022] Figure 2 This is a schematic diagram of the overall disassembled structure of an embodiment of this application;

[0023] Figure 3 This is a schematic diagram of the tail fin morphology of the tail fin deformation propulsion module according to an embodiment of this application;

[0024] Figure 4 This is a schematic diagram of the propeller shape of the tail fin deformation propulsion module according to an embodiment of this application;

[0025] Figure 5 This is a schematic diagram of the tail fin deformation propulsion module switching process from tail fin mode to propeller mode in an embodiment of this application;

[0026] Figure 6 This is a cross-sectional schematic diagram of the integral part of the rotation limiting shell and the tail fin blade in an embodiment of this application;

[0027] Figure 7 This is an exploded structural diagram of the tail fin deformation propulsion module according to an embodiment of this application;

[0028] Figure 8 This is a schematic diagram of the propulsion state under two modes in the embodiments of this application.

[0029] In the diagram, 1 is the head shell, 2 is the first tail swing joint shell, 3 is the second tail swing joint shell, 4 is the tail fin deformation propulsion module, 5 is the first tail fin blade integrated component, 6 is the second tail fin blade integrated component, 7 is the waterproof core compartment, 8 is the first tail swing drive servo, 9 is the first tail swing drive rocker arm, 10 is the second tail swing drive servo, 11 is the second tail swing drive rocker arm, 12 is the brushless drive motor, 13 is the first rotation limit shell, 14 is the second rotation limit shell, 15 is the first driven bevel gear, 16 is the second driven bevel gear, and 17 is the driving bevel gear. Detailed Implementation

[0030] The present invention will be further described and illustrated below with reference to specific embodiments. The embodiments described are merely examples of the content of this disclosure and do not constitute a limitation. The technical features of each embodiment in the present invention can be combined accordingly, provided that there is no mutual conflict.

[0031] It should be noted that all directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present invention are only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indication will also change accordingly.

[0032] Furthermore, in this invention, descriptions involving "first," "second," etc., are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0033] This invention provides a biomimetic robotic fish with a dual-mode propulsion system that combines a deformable tail fin and a propeller. By changing the attitude of the tail fin blades, the same brushless drive motor is used to switch between two propulsion modes, tail fin mode and propeller mode, on the same tail structure, enabling the biomimetic robotic fish to quickly switch between different propulsion modes according to different task stages.

[0034] The bionic robotic fish of this invention adopts an arrangement in which the whole machine is the carrier and the tail propulsion mechanism is the core. That is, the whole machine shell is used to provide the basic structure and control basis of the bionic robotic fish, while the tail fin deformation propulsion module 4 is the core mechanism, enabling the bionic robotic fish to have dual-mode propulsion function including tail fin mode and propeller mode. Figure 1 A schematic diagram of the overall structure of the biomimetic robotic fish proposed in this invention is shown. Figure 2 A schematic diagram of the overall disassembled structure of an embodiment of this application is shown. For example... Figure 1 and Figure 2As shown, the biomimetic robotic fish of the present invention includes a head module, a tail-wagging drive module, and a tail fin deformation propulsion module 4.

[0035] The head module includes a head shell 1, a waterproof core compartment 7, a power supply module, a sensing module, and a main control module. The head shell 1 is assembled from multiple irregularly shaped panels, with the edges of these panels interlocking to form the shape of the biomimetic robotic fish's head. The waterproof core compartment 7 is located inside the head shell 1, housing the power supply module, sensing module, and main control module and providing a dry, sealed environment. The sensing module collects the biomimetic robotic fish's body attitude information and transmits this information to the main control module. The main control module receives the attitude information transmitted by the sensing module and sends corresponding control signals to the tail-wagging drive module and the tail fin deformation propulsion module according to mission requirements. The power supply module provides power to the main control module, sensing module, tail-wagging drive module, and tail fin deformation propulsion module.

[0036] The tail-wagging drive module is used to drive the tail of the bionic robotic fish to swing in tail fin mode, thereby changing the fish's speed and posture. In propeller mode, it is used to adjust the tail posture and control the swimming direction. The tail-wagging drive module includes a first tail-wagging drive servo 8, a first tail-wagging drive rocker arm 9, a second tail-wagging drive servo 10, and a second tail-wagging drive rocker arm 11. Both the first tail-wagging drive rocker arm 9 and the second tail-wagging drive rocker arm 11 are U-shaped rocker arms. The open end of the first tail-wagging drive rocker arm 9 is connected to the upper output shaft of the first tail-wagging drive servo 8 and the lower end of the first tail-wagging drive servo 8, respectively, and the closed end of the first tail-wagging drive rocker arm 9 is the actuating end. The relationship between the second tail-wagging drive servo 10 and the second tail-wagging drive rocker arm 11 is the same as that between the first tail-wagging drive servo 8 and the first tail-wagging drive rocker arm 9. The first tail-swing drive servo 8 is fixedly installed at the rear end of the waterproof core compartment 7, and the second tail-swing drive servo 10 is fixedly installed at the closed end of the first tail-swing drive rocker arm 9. The rear end of the second tail-swing drive rocker arm 11 is connected to the tail fin deformation propulsion module 4. The biomimetic fish shape of the tail-swing drive module is composed of multiple tail-swing joint shells, including the first tail-swing joint shell 2 and the second tail-swing joint shell 3 in this embodiment. The first tail-swing joint shell 2 is fixedly fitted over the second tail-swing drive servo 10 and covers the first tail-swing drive rocker arm 9, so that in the tail fin mode, the first tail-swing drive servo 8 can drive the first tail-swing joint shell 2 to swing left and right through the first tail-swing drive rocker arm 9; the second tail-swing joint shell 3 is fixedly fitted over the front outer side of the tail fin deformation propulsion module 4 and covers the second tail-swing drive rocker arm 11, so that in the tail fin mode, the second tail-swing drive servo 10 can drive the second tail-swing joint shell 3 to swing left and right through the second tail-swing drive rocker arm 11.

[0037] To better simulate the smooth shape of a biomimetic fish, a transition shell can be added to the end of the head module to connect with the tail-wagging drive module.

[0038] The tail fin deformation propulsion module 4 forms a tail structure in the shape of a biomimetic fish, which is used to realize dual-mode propulsion of tail fin mode and propeller mode. Specifically, in mission phases that require good biomimeticity and stealth, the tail fin deformation propulsion module 4 switches to tail fin mode, and in mission phases that require rapid maneuvering or rapid relocation, the tail fin deformation propulsion module 4 switches to propeller mode.

[0039] like Figure 7 As shown, it illustrates an exploded structural diagram of the tail fin deformation propulsion module 4 according to an embodiment of this application. The tail fin deformation propulsion module 4 mainly includes a brushless drive motor 12, an active bevel gear 17, a first driven bevel gear 15, a second driven bevel gear 16, a first tail fin blade integrated component 5, a second tail fin blade integrated component 6, a first rotation limiting shell 13, and a second rotation limiting shell 14.

[0040] The output shaft of the brushless drive motor 12 is connected to the driving bevel gear 17, which meshes with the first driven bevel gear 15 and the second driven bevel gear 16 to form a bevel gear transmission system. Both the first tail fin blade assembly 5 and the second tail fin blade assembly 6 are identical semi-tail fin shaped blades. The root center of both the first tail fin blade assembly 5 and the second tail fin blade assembly 6 has a protruding root cylindrical structure. The center of the root cylindrical structure of the first tail fin blade assembly 5 is fixedly connected to the output shaft of the first driven bevel gear 15, and the center of the root cylindrical structure of the second tail fin blade assembly 6 is fixedly connected to the output shaft of the second driven bevel gear 16. When the brushless drive motor 12 rotates forward, it drives the first tail fin blade assembly 5 and the second tail fin blade assembly 6 to rotate in opposite directions through the bevel gear transmission system until they form a propeller shape with a certain angle (for example, when the first tail fin blade assembly 5 rotates to the left, the second tail fin blade assembly 6 rotates to the right). When the brushless drive motor 12 rotates in reverse, it drives the first tail fin blade assembly 5 and the second tail fin blade assembly 6 to rotate in opposite directions through the bevel gear transmission system until they return to the tail fin shape. In the tail fin mode, there is no angle between the first tail fin blade assembly and the second tail fin blade assembly, which together form a complete tail fin shape.

[0041] The first rotation limiting housing 13 and the second rotation limiting housing 14 are a set of mating irregular-shaped tubular components, which are fitted together on the outside of the tail fin deformation propulsion module 4 and cover the output shaft of the brushless drive motor 12, the driving bevel gear 17, the first driven bevel gear 15 and the second driven bevel gear 16. They are used to install and limit the brushless drive motor 12, the bevel gear transmission system and the corresponding tail fin blade integrated component. Since the front end of the brushless drive motor 12 needs to be connected to the rear end of the second tail swing drive rocker arm 11, the front part of the brushless drive motor 12 is not covered. The top inner side of the mating first rotation limiting housing 13 and the second rotation limiting housing 14 is fixedly connected to the output shaft of the driving bevel gear 17.

[0042] The top sides of the first rotating limiting housing 13 and the second rotating limiting housing 14 are respectively provided with semi-circular annular protrusions, and the inner wall of each semi-circular annular protrusion is provided with an arc-shaped groove along the circumference. After the first rotating limiting housing 13 and the second rotating limiting housing 14 are engaged, the semi-circular annular protrusions on the same side form a complete annular protrusion. The inner diameter of the annular protrusion is the same as the diameter of the root cylindrical structure of the first tail fin blade integrated component 5 and the second tail fin blade integrated component 6, and the root cylindrical structures of the first tail fin blade integrated component 5 and the second tail fin blade integrated component 6 are each embedded in the complete annular protrusion on one side to form a clearance fit.

[0043] The arc-shaped grooves protruding from the semicircular ring on the same side are connected to form a continuous semicircular groove, and the two ends of the semicircular groove form limiting stops, such as... Figure 6 As shown, the limiting stop point on the side near the top of the first rotation limiting shell 13 and the second rotation limiting shell 14 is the tail fin mode limiting point, and the limiting stop point on the side away from the top of the first rotation limiting shell 13 and the second rotation limiting shell 14 is the propeller mode limiting point. Both the root cylindrical structure of the first tail fin blade assembly 5 and the second tail fin blade assembly 6 are provided with protruding wedge-shaped blocks. The cross-section of the wedge-shaped blocks is consistent with the cross-section of the semi-circular groove and can slide within the semi-circular groove. The first tail fin blade assembly 5 and the second tail fin blade assembly 6 rotate until the wedge-shaped blocks abut against the tail fin mode limiting point or the propeller mode limiting point. The semi-circular grooves on both sides are configured to allow the first tail fin blade assembly 5 and the second tail fin blade assembly 6 to rotate in opposite directions.

[0044] like Figure 3 The diagram shows a schematic of the tail fin modal structure of the tail fin deformable propulsion module according to an embodiment of this application. In tail fin mode, the first tail fin blade integrated component 5 and the second tail fin blade integrated component 6 are combined to form a complete bionic tail fin, with an overall shape similar to a regular fish tail. In this mode, the tail fin deformable propulsion module 4 swings along with the front tail-wagging drive module, thus forming a tail fin swinging propulsion method similar to that of a regular bionic robotic fish. At this time, the brushless drive motor 12 does not directly serve as a propulsion power source. Because Figure 3 The second rotation limiting housing 14 is obscured in the front view; only the first rotation limiting housing 13 is shown. In this embodiment, the torque generated by the tail-wagging water flow in the tail fin mode on the first tail fin blade assembly 5 and the second tail fin blade assembly 6 is transmitted through a bevel gear transmission system and is generally in a state of mutual balance. When a deviation occurs, it can be corrected by the brushless drive motor 12, thereby preventing the spontaneous switching to propeller mode due to external disturbances in the tail fin mode. The method of correction by the brushless drive motor 12 is that when the first tail fin blade assembly 5 and the second tail fin blade assembly 6 are subjected to external disturbances and show a tendency to spontaneously switch to propeller mode, the brushless drive motor 12 reverses, providing torque to counteract the disturbance and maintain the tail fin mode, thereby preventing abnormal switching from the tail fin mode to the propeller mode.

[0045] like Figure 4 The diagram illustrates the propeller mode structure of the tail fin deformation propulsion module according to an embodiment of this application. In propeller mode, the first tail fin blade assembly 5 and the second tail fin blade assembly 6 are a double-bladed propeller with a certain angle offset. When the fish body is not swaying, the propeller axis direction coincides with the central axis direction of the bionic robotic fish, and the first tail fin blade assembly 5 and the second tail fin blade assembly 6 maintain their shape by continuous drive from the brushless drive motor 12. The brushless drive motor 12 serves as a direct propulsion power source, outputting power through the active bevel gear 17 to drive the first rotation limiting housing 13 and the second rotation limiting housing 14, thereby causing the tail fin deformation propulsion module 4 to rotate as a whole, achieving propeller propulsion. Figure 4 This is a front view; the second rotation limiting housing 14 is obscured, and only the first rotation limiting housing 13 is shown in the figure.

[0046] like Figure 8 As shown, this diagram illustrates the propulsion states under two modes according to an embodiment of this application. In the tail fin mode, the tail-wagging drive module drives the tail to swing, and the tail fin deformation propulsion module 4 participates in the tail-wagging propulsion as a whole, while the brushless drive motor 12 only performs the function of maintaining or correcting the tail fin mode. In the propeller mode, propulsion is mainly achieved by the brushless drive motor 12 driving the tail fin deformation propulsion module 4 to rotate as a whole. The tail-wagging drive module does not undertake the propeller rotation drive function, but the direction adjustment or motion fine-tuning can be achieved by adjusting the tail attitude. Thus, the biomimetic robotic fish can select the tail fin mode or the propeller mode according to different task stages, thereby taking into account both the needs of biomimetic approach and rapid maneuvering.

[0047] When switching from propeller mode to tail fin mode, the brushless drive motor 12 reverses and drives the first tail fin blade assembly 5 and the second tail fin blade assembly 6 to rotate and deform around their respective root cylindrical structures through the bevel gear transmission system until the wedge block abuts against the tail fin mode limit point, and the first tail fin blade assembly 5 and the second tail fin blade assembly 6 return to the tail fin shape.

[0048] like Figure 5 As shown, this diagram illustrates the intermediate state of the tail fin deformation propulsion module 4 during the transition from tail fin mode to propeller mode in this embodiment of the application. During this process, the brushless drive motor 12 rotates forward, driving the first tail fin blade assembly 5 and the second tail fin blade assembly 6 to rotate relative to each other around their respective root cylindrical structures along the illustrated rotation axis in the illustrated direction, until the wedge-shaped blocks of the first tail fin blade assembly 5 and the second tail fin blade assembly 6 abut against the propeller mode limiting point, thus transforming into a double-bladed propeller shape with a certain angle offset.

[0049] This invention also provides a method for the same-body dual-mode propulsion of a biomimetic robotic fish based on the aforementioned dual-mode propulsion of the tail fin and propeller deforming together, specifically including:

[0050] During mission phases requiring good biomimicry and stealth, the tail fin deformable propulsion module 4 is in tail fin mode, with the first tail fin blade assembly 5 and the second tail fin blade assembly 6 forming a tail fin shape. The main control module sends control signals to the tail-swinging drive module, and the first tail-swinging drive servo 8 and the second tail-swinging drive servo 10 respectively drive the first tail-swinging drive rocker arm 9 and the second tail-swinging drive rocker arm 11 to move, thereby causing the first tail-swinging joint housing 2 and the second tail-swinging joint housing 3 to move, which in turn drives the tail deformable propulsion module 4 to swing left and right, providing propulsion power for the biomimetic robotic fish. Simultaneously, the sensing module collects the biomimetic robotic fish's body posture information and transmits it to the main control module. When a deviation in the body posture is detected, the main control module sends a control signal to the brushless drive motor 12, causing the brushless drive motor 12 to reverse and correct the body posture, preventing the automatic switch to propeller mode due to external disturbances in tail fin mode.

[0051] During missions requiring rapid maneuvering or relocation, the tail fin deformable propulsion module 4 operates in propeller mode, with the first tail fin blade assembly 5 and the second tail fin blade assembly 6 forming a propeller shape. The main control module sends control signals to the brushless drive motor 12, controlling the motor to rotate the entire tail fin deformable propulsion module 4, thereby propelling the bionic robotic fish forward. Simultaneously, the sensing module collects the bionic robotic fish's body posture information and transmits it to the main control module. When a deviation in body posture or swimming direction is detected, the main control module sends control signals to the tail-wagging drive module, which fine-tunes the body posture or swimming direction through tail-wagging movements.

[0052] When switching from a mission phase requiring good biomimicry and stealth to a mission phase requiring rapid maneuverability or rapid relocation, the tail fin deformation propulsion module 4 needs to switch from tail fin mode to propeller mode. The main control module sends a control signal to the brushless drive motor 12, which rotates forward and drives the first tail fin blade assembly 5 and the second tail fin blade assembly 6 to rotate and deform through the bevel gear transmission system until the wedge-shaped blocks abut against the propeller mode limit point. Subsequently, the wedge-shaped blocks of the first tail fin blade assembly 5 and the second tail fin blade assembly 6 are stably abutted against the propeller mode limit point under the continuous drive of the brushless drive motor 12, thereby maintaining a stable propeller shape; the tail fin deformation propulsion module 4 rotates as a whole under the continuous drive of the brushless drive motor 12, providing power for the fish's swimming.

[0053] When switching from a mission phase requiring rapid maneuverability or relocation to one demanding better biomimicry and stealth, the tail fin deformable propulsion module 4 needs to switch from propeller mode to tail fin mode. The main control module sends a control signal to the brushless drive motor 12, causing the brushless drive motor 12 to reverse. After the tail fin deformable propulsion module 4 stops rotating, the wedge-shaped blocks of the first tail fin blade assembly 5 and the second tail fin blade assembly 6 are driven by the bevel gear transmission system to abut against the tail fin mode limit point, thus restoring it to the tail fin shape. The brushless drive motor 12 then stops operating. Subsequently, the tail-wagging drive module uses the tail-wagging motion of released fish to drive the tail fin deformable propulsion module 4 to swing, achieving propulsion.

[0054] In summary, this invention constructs the first and second tail fin blades into a single deformable structure that can switch between tail fin mode and propeller mode, enabling the biomimetic robotic fish to achieve dual-mode propulsion while maintaining the shape of the biomimetic tail fin. At the same time, it utilizes the same brushless drive motor to handle both mode switching drive and rotational propulsion in propeller mode, eliminating the need for a separate dedicated mode switching power source. This improves the adaptability and maneuverability of the biomimetic robotic fish in different mission stages and underwater environments.

[0055] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements all fall within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the appended claims.

Claims

1. A biomimetic robotic fish with a dual-mode propulsion system, characterized in that, The biomimetic robotic fish includes a head module, a tail-wagging drive module, and a tail fin deformation propulsion module connected in sequence. The head module forms the shape of a biomimetic robotic fish head, and electronic components are installed inside the head module. The tail-wagging drive module includes a multi-section chain-connected tail-wagging joint, which is used to form the shape of the middle section of the biomimetic robotic fish, and drives the tail fin to wag by swinging left and right through the tail-wagging joint. The tail fin deformation propulsion module constitutes the tail structure of the biomimetic robotic fish, used to achieve dual-mode propulsion of tail fin mode and propeller mode. The tail fin deformation propulsion module includes a first integrated tail fin blade, a second integrated tail fin blade, and a tail fin drive system. Both the first and second integrated tail fin blades are semi-tail fin shaped blades, and their roots are connected to the tail fin drive system, which is connected to the rear end of the tail-swinging drive module. The tail fin drive system includes a brushless drive motor, a driving bevel gear, a first driven bevel gear, and a second driven bevel gear. The driving bevel gear is fixedly connected to the output shaft of the brushless drive motor. The gears mesh with the first driven bevel gear and the second driven bevel gear respectively to form a bevel gear transmission system; the output shaft of the first driven bevel gear is fixedly connected to the center of the root of the first tail fin blade assembly, and the output shaft of the second driven bevel gear is fixedly connected to the center of the root of the second tail fin blade assembly; the tail fin deformation propulsion module also includes a set of mating irregular-shaped tubes, which are fixedly sleeved outside the tail fin drive system; the top of the mating irregular-shaped tubes is fixedly connected to the output shaft of the active bevel gear. When the first tail fin blade assembly and the second tail fin blade assembly rotate to a preset angle, the brushless drive motor drives the mating irregular-shaped tubes through the bevel gear system, thereby driving the tail fin deformation propulsion module to rotate as a whole, thus realizing propeller propulsion; The first tail fin blade assembly and the second tail fin blade assembly have a root cylindrical structure at their root center. The mating irregular-shaped tubular fitting includes a first rotating limiting shell and a second rotating limiting shell; the top sides of the first rotating limiting shell and the second rotating limiting shell are respectively provided with semi-circular protrusions, and the semi-circular protrusions on the same side are mated to form a complete circular protrusion. The inner diameter of the circular protrusion is the same as the diameter of the root cylindrical structure of the first tail fin blade integrated piece and the second tail fin blade integrated piece, and the root cylindrical structure of the first tail fin blade integrated piece and the second tail fin blade integrated piece are each embedded in the circular protrusion on one side to form a rotating pair. The inner wall of the semi-circular ring protrusion is provided with an arc-shaped groove along the circumference. The arc-shaped grooves of the semi-circular ring protrusion on the same side are connected to form a connected semi-circular groove, and the two ends of the semi-circular groove form a limiting stop point. The cylindrical structure at the root of the first tail fin blade assembly and the second tail fin blade assembly are provided with protruding wedge-shaped blocks. When the first tail fin blade assembly and the second tail fin blade assembly rotate, the wedge-shaped blocks slide in the semi-circular groove. The first tail fin blade assembly and the second tail fin blade assembly stop rotating when the wedge-shaped blocks abut against the limiting stop point. In the caudal fin mode, there is no included angle between the first caudal fin blade integrated component and the second caudal fin blade integrated component, together forming a complete caudal fin shape. In propeller mode, the first tail fin blade assembly and the second tail fin blade assembly rotate in opposite directions around their respective roots to a predetermined angle under the drive of the tail fin drive system, together forming a double-bladed propeller structure. The tail fin deformation propulsion module rotates around the axis of the two-bladed propeller under the drive of the tail fin drive system, providing propulsion power for the bionic robotic fish to swim.

2. The biomimetic robotic fish with dual-mode propulsion, featuring a co-existing tail fin and propeller as described in claim 1, is characterized in that... The limiting stop point on the side closer to the top of the mating irregular tube is the tail fin mode limiting point, and the limiting stop point on the side farther from the top of the mating irregular tube is the propeller mode limiting point. When the brushless drive motor rotates forward, the first tail fin blade assembly and the second tail fin blade assembly rotate until the wedge block abuts against the propeller mode limit point, forming a double-bladed propeller structure, and maintaining its shape due to the continuous drive of the brushless drive motor; when the brushless drive motor rotates in reverse, the first tail fin blade assembly and the second tail fin blade assembly rotate until the wedge block abuts against the tail fin mode limit point, restoring the tail fin shape.

3. The biomimetic robotic fish with dual-mode propulsion, featuring a co-existing tail fin and propeller, as described in claim 1, is characterized in that... The tail-swing joint includes a tail-swing drive servo, a tail-swing drive rocker arm, and a tail-swing joint housing. The tail-swing drive rocker arm is connected to the tail-swing drive servo, and the joint housing is fitted over the tail-swing drive rocker arm and the tail-swing joint housing. Each joint housing section corresponds to a set of tail-swing drive rocker arms and tail-swing joint housings. The tail-swing drive rocker arm swings left and right under the drive of the tail-swing drive servo, causing the corresponding joint housing to swing; the first tail-swing drive servo is fixed inside the head module; the rear end of the last tail-swing drive rocker arm is connected to the tail fin drive system.

4. The biomimetic robotic fish with dual-mode propulsion, characterized by the integral deformation of the tail fin and propeller as described in claim 1, is characterized in that... The head module contains a waterproof core compartment, as well as a main control module, a sensing module, and a power supply module located within the waterproof core compartment.

5. The biomimetic robotic fish with dual-mode propulsion, characterized by the co-existence deformation of the tail fin and propeller as described in claim 1, is characterized in that... In the tail fin mode, when the first tail fin blade assembly and the second tail fin blade assembly deviate in attitude due to the tail wagging water flow, the brushless drive motor reverses to provide torque to counteract the water flow disturbance and maintain the tail fin mode, thereby correcting the first tail fin blade assembly and the second tail fin blade assembly and preventing the tail fin deformation propulsion module from automatically switching to propeller mode.

6. A method for dual-mode propulsion of a biomimetic robotic fish based on the co-existing deformable tail fin and propeller dual-mode propulsion described in claim 1, characterized in that, include: When the tail fin deformation propulsion module switches from tail fin mode to propeller mode, the brushless drive motor rotates forward, driving the first tail fin blade assembly and the second tail fin blade assembly to rotate to a preset angle through the bevel gear transmission system, forming a double-bladed propeller structure. Subsequently, the first tail fin blade assembly and the second tail fin blade assembly stabilize at their current positions under the continuous drive of the brushless drive motor, thus maintaining a stable double-bladed propeller structure. The mating irregular-shaped tube rotates under the continuous drive of the brushless drive motor, driving the tail fin deformation propulsion module to rotate as a whole, realizing propeller propulsion. When the tail fin deformation propulsion module switches from propeller mode to tail fin mode, the brushless drive motor reverses, causing the entire tail fin deformation propulsion module to stop rotating. Then, through the bevel gear transmission system, it drives the first tail fin blade assembly and the second tail fin blade assembly to rotate to a point without angle, restoring the complete tail fin shape. The brushless drive motor then stops rotating. Subsequently, the tail swing drive module drives the tail fin deformation propulsion module to swing and achieve propulsion.

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