Intelligent bionic fish based on piezoelectric fiber material and shape memory alloy and driving method

Abstract

The invention provides an intelligent bionic fish based on a piezoelectric fiber material and a shape memory alloy and a driving method.The intelligent bionic fish comprises a piezoelectric fiber material driving layer, a shape memory alloy driving layer and a cooperative control module, the piezoelectric fiber material driving layer comprises a plurality of MFC pasters embedded in flexible fins of the bionic fish, and the MFC pasters are connected with the shape memory alloy driving layer; the fins are excited to resonate through high-frequency vibration to generate low-amplitude swing; the shape memory alloy driving layer comprises an SMA spring array which is embedded in the annular fish body structure, and SMA springs are driven to rapidly contract through electric heating to achieve overall large-scale bending deformation and local form change of the bionic fish; and the cooperative control module is arranged at the fish head, and adopts a layered driving strategy and time sequence cooperative control logic to dynamically combine action modes of the piezoelectric fiber material driving layer and the shape memory alloy driving layer. By complementarily utilizing the rapid deformation capacity of the SMA and the high-frequency driving characteristic of the MFC, the performance bottleneck of a single driver is broken through, and the underwater maneuverability and energy efficiency of the bionic fish are improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of underwater robots, in particular, especially relates to an intelligent bionic fish based on piezoelectric fiber material and shape memory alloy and a driving method. BACKGROUND

[0002] As an important tool for ocean exploration and operation, underwater robots have always been a hot research topic in driving technology. The application of bionics principles in underwater robot design aims to improve the maneuverability, energy efficiency and adaptability of underwater robots by imitating the movement patterns and structural characteristics of living organisms. For example, fish achieve efficient swimming through the swinging of their fins and the bending of their bodies. This movement pattern has unique advantages in underwater environments, such as low energy consumption, high maneuverability and good silence. Therefore, researching underwater robot driving technology based on bionic principles is of great significance for developing new underwater exploration, pipeline inspection and other applications. In existing underwater bionic robot technology, common driving methods include motor-driven, hydraulic-driven, etc. Although motor-driven underwater robots can achieve certain movement functions, they usually have problems such as large size, high energy consumption, and loud noise, which limit their application in certain specific scenarios. Hydraulic-driven systems are complex and have a risk of leakage, making them unsuitable for some underwater tasks that require a high level of environmental protection. In addition, some research has attempted to use single new driving materials such as piezoelectric materials or shape memory alloys, but these single driving methods often have performance bottlenecks and cannot meet the comprehensive needs of underwater robots for high efficiency, high maneuverability and fast response. Although existing underwater robot driving technology meets some application needs to a certain extent, it still has some obvious defects. For example, motor-driven and hydraulic-driven underwater robots perform poorly in terms of energy efficiency and maneuverability, making it difficult for them to adapt to complex and changing underwater environments. The use of single new driving materials, such as only using piezoelectric materials or shape memory alloys, has advantages in some aspects, but cannot fully utilize the advantages of each material, resulting in limited overall performance. In addition, there is a lack of a solution in existing technology that effectively combines the advantages of multiple driving materials to achieve efficient switching and collaborative control of underwater robots in different movement modes. Therefore, developing a new type of underwater bionic robot driving technology to overcome the shortcomings of existing technology and improve the overall performance of underwater robots is an important direction for current research. SUMMARY

[0003] The application discloses an intelligent bionic fish based on piezoelectric fiber material and shape memory alloy and a driving method.

[0004] The application adopts the following technical means: The application discloses an intelligent bionic fish based on piezoelectric fiber material and shape memory alloy, which comprises a piezoelectric fiber material (MFC) driving layer, a shape memory alloy (SMA) driving layer and a cooperative control module. The piezoelectric fiber material (MFC) driving layer comprises a plurality of MFC patches and is embedded in a flexible fin of the bionic fish, and low-amplitude oscillation is generated by exciting the fin resonance through high-frequency vibration. The shape memory alloy (SMA) driving layer comprises an SMA spring array and is embedded in a ring-shaped fish body structure, and large-scale bending deformation and local shape change of the whole bionic fish are realized by rapidly contracting the SMA spring through electric heating driving. The cooperative control module is arranged at the head of the fish, adopts a layered driving strategy and a time sequence cooperative control logic, and dynamically combines the action modes of the piezoelectric fiber material (MFC) driving layer and the shape memory alloy (SMA) driving layer.

[0005] Further, the piezoelectric fiber material (MFC) driving layer comprises small piezoelectric fiber patches, anal fins, large piezoelectric fiber patches and a tail fin. The four anal fins are symmetrically distributed vertically to the center of the spine and are located in front of the tail fin, and are used for providing auxiliary propulsion force and stability during swimming. The large piezoelectric fiber patch is embedded in the tail fin and is used for exciting the tail fin to generate high-frequency low-amplitude resonance through high-frequency vibration, so that efficient propulsion effect is realized. The small piezoelectric fiber patch is arranged in multiple pieces, each two pieces are embedded in each anal fin, and each two pieces of small piezoelectric fiber patches have a phase difference, and are used for cooperating with the vibration of the large piezoelectric fiber patch of the tail fin, so as to further optimize the propulsion effect. The tail fin is arranged in one piece and is located at the tail of the bionic fish, and is used for generating main propulsion force.

[0006] Further, the shape memory alloy (SMA) driving layer comprises a ring-shaped fish body exoskeleton, a flexible fish body spine, an internal shape memory alloy spring array and an external shape memory alloy spring array. The ring-shaped fish body exoskeleton is used for constituting the support structure of the fish body and providing the overall shape and strength. The flexible fish spine is located at the center of the annular fish exoskeleton and is used for connecting the annular fish exoskeletons, maintaining the flexibility and bendability of the fish body. The internal shape memory alloy spring array is arranged in a central symmetry perpendicular to the flexible fish spine, is connected with the fish spine and the annular fish exoskeleton, and realizes the change of the local shape of the fish body through the energization contraction, so that the bending degree and direction of the fish body are adjusted. The external shape memory alloy spring array is uniformly arranged in parallel to the flexible fish spine, longitudinally connects the annular fish exoskeletons in series, realizes the rapid turning of the fish body through the energization contraction of the springs on the turning side, and quickly adjusts the moving direction of the fish body.

[0007] Further, the cooperative control module includes three driving modes of high-speed cruising, burst acceleration and emergency turning, wherein: The high-speed cruising mode only activates the piezoelectric fiber material (MFC) driving layer, is used for matching the water flow characteristics for resonance, and realizes the steady-state swimming. The burst acceleration mode triggers the rapid bending contraction of the shape memory alloy (SMA) driving layer, synchronously superimposes the fine adjustment of the attack angle of the tail fin by the piezoelectric fiber material (MFC) driving layer, and is used for realizing the rapid acceleration. The emergency turning mode realizes the rapid attitude correction through the contraction of the unilateral SMA spring array combined with the high-frequency braking of the opposite MFC patch.

[0008] The application also provides a bionic fish driving method based on the above-mentioned intelligent bionic fish based on the piezoelectric fiber material and the shape memory alloy, comprising: The water flow state and the motion instruction are acquired through the sensor. According to the driving mode of the target, the corresponding driving layer is activated, wherein the high-speed cruising mode only starts the piezoelectric fiber material (MFC) driving layer; the burst acceleration mode synchronously activates the piezoelectric fiber material (MFC) driving layer and the shape memory alloy (SMA) driving layer; and the emergency turning mode executes the contraction of the unilateral SMA spring array and the braking of the opposite MFC patch. The heating power of the SMA spring array and the vibration phase difference of the MFC patch are adjusted in real time, so as to optimize the propulsion efficiency.

[0009] Further, the sensor includes a water flow sensor, an attitude sensor and a position sensor, wherein: The water flow sensor is used for monitoring the water flow speed in real time. The attitude sensor is used for monitoring the bionic fish attitude in real time. The position sensor is used for monitoring the bionic fish position in real time.

[0010] Further, the process of real-time adjusting the heating power of the SMA spring array and the vibration phase difference of the MFC patch is realized through a closed-loop control system, which automatically adjusts the heating power and the vibration phase difference according to the information fed back by the sensor, so that the bionic fish can maintain the best propulsion efficiency and stability under different water flow conditions and motion modes.

[0011] Compared with the prior art, the present application has the following advantages: 1. The intelligent bionic fish based on piezoelectric fiber material and shape memory alloy provided by the present application utilizes the high-frequency vibration characteristics of the piezoelectric fiber material (MFC) to excite the resonance effect of the fish fin, generates low-amplitude high-frequency fluctuations, and thus realizes high-efficiency propulsion in the cruising mode, significantly reduces energy consumption, and prolongs the endurance time of the bionic fish.

[0012] 2. The intelligent bionic fish based on piezoelectric fiber material and shape memory alloy provided by the present application realizes large-scale and fast-response bending and turning actions of the bionic fish through the electrothermal driving characteristics of the shape memory alloy (SMA), so that the bionic fish can quickly adjust the posture in the emergency turning mode and improve the maneuverability in complex underwater environments.

[0013] 3. The intelligent bionic fish based on piezoelectric fiber material and shape memory alloy provided by the present application adopts a layered driving control and time sequence cooperative control strategy, dynamically combines the action modes of the SMA driving layer and the MFC driving layer, realizes efficient switching of the three modes of high-speed cruising, burst acceleration and emergency turning, and adapts to different underwater task requirements.

[0014] 4. The intelligent bionic fish based on piezoelectric fiber material and shape memory alloy provided by the present application can adapt to different water flow conditions, optimizes the propulsion efficiency by real-time adjusting the SMA heating power and the MFC vibration phase difference, is suitable for various application scenarios such as underwater detection and pipeline inspection, and has a wide application prospect. BRIEF DESCRIPTION OF DRAWINGS

[0015] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed to be used in the embodiments or prior art description will be briefly introduced. Obviously, the drawings in the following description are some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without creative labor.

[0016] Figure 1 It is the overall structure diagram of the intelligent bionic fish of the present application.

[0017] Figure 2 It is the structure diagram of the piezoelectric fiber material (MFC) driving layer of the present application.

[0018] Figure 3 Figure 1 is a structure diagram of a shape memory alloy (SMA) driving layer of the present application.

[0019] Figure 4 Figure 2 is a flow chart of a method of the present application.

[0020] Figure 1 is a structure diagram of a shape memory alloy (SMA) driving layer of the present application. DETAILED DESCRIPTION

[0021] In order to make the personnel in the technical field better understand the present application scheme, the technical scheme in the embodiments of the present application will be described clearly and completely in combination with the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, not all. Based on the embodiments in the present application, all other embodiments obtained by the person skilled in the art without creative labor should belong to the protection scope of the present application.

[0022] It should be noted that the terms "first", "second" and the like in the specification and claims of the present application and the above-described drawings are used to distinguish similar objects, and do not necessarily indicate a specific order or a chronological sequence. It should be understood that the data thus used can be interchanged under appropriate circumstances, so that the embodiments of the present application described herein can be implemented in an order other than that illustrated or described herein. In addition, the terms "include" and "have" and any variations thereof are intended to cover non-exclusive inclusion, for example, a process, method, system, product or device including a series of steps or units does not necessarily have to be limited to those steps or units clearly listed, but can include other steps or units not clearly listed or inherent to these processes, methods, products or devices.

[0023] As shown in Figure 1 The present application provides an intelligent bionic fish based on piezoelectric fiber material and shape memory alloy, comprising: a piezoelectric fiber material driving layer 1, a shape memory alloy driving layer 2 and a cooperative control module 3, wherein: The piezoelectric fiber material driving layer 1 comprises a plurality of MFC patches embedded in the flexible fish fin of the bionic fish, and generates low amplitude oscillation by exciting the fin resonance through high frequency vibration; The shape memory alloy driving layer 2 comprises an SMA spring array embedded in the ring-shaped fish body structure, and realizes the large-scale bending deformation and local shape change of the whole bionic fish by rapidly contracting the SMA spring driven by electricity and heat; The collaborative control module 3 is located at the fish head and adopts a hierarchical driving strategy and timing collaborative control logic to dynamically combine the action modes of the piezoelectric fiber material driving layer 1 and the shape memory alloy driving layer 2.

[0024] In specific implementation, as a preferred embodiment of the present invention, such as Figure 2 As shown, the piezoelectric fiber material driving layer 1 includes a small piezoelectric fiber patch 11, an anal fin 12, a large piezoelectric fiber patch 13, and a caudal fin 14, wherein: The anal fin 12 has four pieces, and the four anal fins 12 are symmetrically distributed perpendicular to the center of the spine and located in front of the caudal fin 14, which are used to provide auxiliary propulsion and stability during swimming. The large piezoelectric fiber patch 13 is embedded in the tail fin 14 and is used to excite the tail fin to generate high-frequency low-amplitude resonance through high-frequency vibration, thereby achieving a highly efficient propulsion effect. Multiple small piezoelectric fiber patches 11 are provided, with two patches embedded on each anal fin 12, and each pair of small piezoelectric fiber patches 11 has a phase difference, which is used to coordinate the vibration of the large piezoelectric fiber patch 13 of the caudal fin 14 to further optimize the propulsion effect. The tail fin 14 is a single piece located at the tail of the biomimetic fish and is used to generate the main propulsion force.

[0025] In specific implementation, as a preferred embodiment of the present invention, such as Figure 3 As shown, the shape memory alloy driving layer 2 includes a ring-shaped fish exoskeleton 21, a flexible fish spine 22, an internal shape memory alloy spring array 23, and an external shape memory alloy spring array 24, wherein: The ring-shaped fish exoskeleton 21 is used to form a supporting structure for the fish body, providing overall shape and strength; The flexible fish spine 22 is located at the center of the annular fish exoskeleton 21 and is used to connect the segments of the annular fish exoskeleton 21 to maintain the flexibility and bendability of the fish body. The internal shape memory alloy spring array 23 is arranged symmetrically with respect to the spine 22 of the flexible fish body, connecting the spine of the fish to the ring-shaped exoskeleton 21. It can achieve changes in the local shape of the fish body by contracting through electricity, thereby adjusting the degree and direction of the fish body's curvature. The external shape memory alloy spring array 24 is evenly arranged parallel to the flexible fish spine 22, and the segments of the annular fish exoskeleton 21 are connected in series longitudinally. By energizing the springs on the steering side and causing them to contract violently, the fish can quickly turn and thus rapidly adjust its direction of movement.

[0026] In a specific implementation, as a preferred embodiment of the present invention, the cooperative control module 3 includes three driving modes: high-speed cruise, burst acceleration, and emergency steering, wherein: The high-speed cruising mode only activates the piezoelectric fiber material driving layer 1 to match the water flow characteristics to resonate and realize stable swimming. The burst acceleration mode triggers the rapid bending and contraction of the shape memory alloy driving layer 2, and synchronously superimposes the fine adjustment of the tail fin attack angle by the piezoelectric fiber material driving layer 1, to realize rapid acceleration. The emergency steering mode realizes rapid attitude correction through unilateral SMA spring array contraction combined with contralateral MFC patch high-frequency braking.

[0027] The application also provides a bionic fish driving method based on the above-mentioned piezoelectric fiber material and shape memory alloy based intelligent bionic fish, as shown in the figure, comprising: Figure 4 Obtaining the water flow state and motion instructions through a sensor; According to the target driving mode, the corresponding driving layer is activated, wherein the high-speed cruising mode only starts the piezoelectric fiber material driving layer 1; the burst acceleration mode synchronously activates the piezoelectric fiber material driving layer 1 and the shape memory alloy driving layer 2; the emergency steering mode executes unilateral SMA spring array contraction and contralateral MFC patch braking; Real-time adjustment of the heating power of the SMA spring array and the vibration phase difference of the MFC patch to optimize the propulsion efficiency.

[0028] In specific implementation, as a preferred embodiment of the application, the sensor comprises a water flow sensor, an attitude sensor and a position sensor, wherein: The water flow sensor is used to monitor the water flow speed in real time; The attitude sensor is used to monitor the bionic fish attitude in real time The position sensor is used to monitor the bionic fish position in real time.

[0029] In specific implementation, as a preferred embodiment of the application, the process of real-time adjustment of the heating power of the SMA spring array and the vibration phase difference of the MFC patch is realized through a closed-loop control system, which automatically adjusts the heating power and the vibration phase difference according to the information fed back by the sensor, to ensure that the bionic fish can maintain the best propulsion efficiency and stability under different water flow conditions and motion modes.

[0030] In the above-mentioned embodiments of the application, the description of each embodiment has its own focus, and the parts not described in detail in a certain embodiment can be referred to the relevant description of other embodiments.

[0031] ​In several embodiments provided in the present application, it should be understood that the disclosed technical contents can be implemented by other manners. Among them, the above-described device embodiments are only illustrative, for example, the division of the units can be a logical function division, and actual implementation can have another division manner, for example, a plurality of units or components can be combined or integrated into another system, or some features can be ignored or not executed. In addition, the coupling or direct coupling or communication connection between the units or modules shown or discussed can be indirect coupling or communication connection through some interfaces, units or modules, which can be electrical or other forms.

[0032] The units described as separate components can or can not be physically separated, and the components shown as units can or can not be physical units, that is, they can be located in one place or distributed on multiple units. Part or all of the units can be selected to achieve the purpose of the embodiment scheme according to actual needs.

[0033] In addition, the functional units in each embodiment of the present application can be integrated in one processing unit, or each unit can exist physically, or two or more units can be integrated in one unit. The integrated unit can be realized in the form of hardware or in the form of a software functional unit.

[0034] When the integrated unit is realized in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer readable storage medium. Based on such understanding, the technical solutions of the present application essentially or the part that contributes to the prior art or the whole or part of the technical solutions can be embodied in the form of a software product. The computer software product is stored in a storage medium, including a plurality of instructions to make a computer device (which can be a personal computer, a server or a network device, etc.) execute all or part of the steps of the method described in each embodiment of the present application. The foregoing storage medium includes: a U disk, a read-only memory (ROM, Read-Only Memory), a random access memory (RAM, Random Access Memory), a mobile hard disk, a magnetic disk or an optical disk, and various media that can store program codes.

[0035] Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present application, and not to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that: it can still modify the technical solutions recorded in the foregoing embodiments, or make equivalent replacement for part or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A smart biomimetic fish based on piezoelectric fiber materials and shape memory alloys, characterized in that, include: The piezoelectric fiber material driving layer (1), the shape memory alloy driving layer (2), and the collaborative control module (3) are as follows: The piezoelectric fiber material driving layer (1) includes multiple MFC patches embedded in the bionic fish flexible fin, which generates low-amplitude oscillation by exciting the fin resonance through high-frequency vibration. The shape memory alloy driving layer (2) includes an SMA spring array embedded in the annular fish body structure. The SMA spring is driven by electrothermal energy to rapidly contract, thereby realizing the large-scale bending deformation and local morphological changes of the bionic fish as a whole. The collaborative control module (3) is located at the fish head and adopts a hierarchical driving strategy and a time-series collaborative control logic to dynamically combine the action modes of the piezoelectric fiber material driving layer (1) and the shape memory alloy driving layer (2).

2. The intelligent biomimetic fish based on piezoelectric fiber material and shape memory alloy according to claim 1, characterized in that, The piezoelectric fiber material driving layer (1) includes a small piezoelectric fiber patch (11), an anal fin (12), a large piezoelectric fiber patch (13), and a caudal fin (14), wherein: The anal fin (12) has four pieces, and the four anal fins (12) are symmetrically distributed perpendicular to the center of the spine and located in front of the caudal fin (14) to provide auxiliary propulsion and stability during swimming. The large piezoelectric fiber patch (13) is embedded in the tail fin (14) and is used to generate high-frequency low-amplitude resonance by exciting the tail fin through high-frequency vibration, thereby achieving a high-efficiency propulsion effect. The small piezoelectric fiber patch (11) is provided in multiple pieces, with two pieces embedded on each anal fin (12), and each pair of small piezoelectric fiber patches (11) has a phase difference, which is used to coordinate the vibration of the large piezoelectric fiber patch (13) of the caudal fin (14) to further optimize the propulsion effect. The caudal fin (14) is provided as a piece located at the tail of the biomimetic fish and is used to generate the main propulsion force.

3. The intelligent biomimetic fish based on piezoelectric fiber material and shape memory alloy according to claim 1, characterized in that, The shape memory alloy driving layer (2) includes a ring-shaped fish exoskeleton (21), a flexible fish spine (22), an internal shape memory alloy spring array (23), and an external shape memory alloy spring array (24), wherein: The ring-shaped fish exoskeleton (21) is used to form the supporting structure of the fish body, providing overall shape and strength; The flexible fish spine (22) is located at the center of the annular fish exoskeleton (21) and is used to connect the segments of the annular fish exoskeleton (21) to maintain the flexibility and bendability of the fish body; The internal shape memory alloy spring array (23) is arranged symmetrically with respect to the flexible fish spine (22), connecting the fish spine and the ring-shaped fish exoskeleton (21). It achieves local shape changes of the fish body by contracting through electricity, thereby adjusting the degree and direction of the fish body's curvature. The external shape memory alloy spring array (24) is evenly arranged parallel to the flexible fish spine (22), and the segments of the annular fish exoskeleton (21) are connected in series longitudinally. By energizing the spring on the turning side and causing it to contract violently, the fish body can quickly turn and thus rapidly adjust the direction of movement of the fish body.

4. The intelligent biomimetic fish based on piezoelectric fiber material and shape memory alloy according to claim 1, characterized in that, The collaborative control module (3) includes three driving modes: high-speed cruise, burst acceleration, and emergency steering, wherein: The high-speed cruise mode activates only the piezoelectric fiber material driving layer (1) to match the water flow characteristics for resonance and achieve steady-state swimming. The burst acceleration mode triggers the rapid bending and contraction of the shape memory alloy driving layer (2), and simultaneously superimposed the piezoelectric fiber material driving layer (1) to fine-tune the angle of attack of the tail fin, in order to achieve rapid acceleration; The emergency steering mode uses a combination of single-sided SMA spring array contraction and high-frequency braking via the opposite-sided MFC patch to achieve rapid attitude correction.

5. A biomimetic fish driving method based on the intelligent biomimetic fish based on piezoelectric fiber materials and shape memory alloys as described in any one of claims 1-4, characterized in that, include: The water flow status and movement commands are obtained through sensors; The corresponding drive layer is activated according to the target's drive mode. In the high-speed cruise mode, only the piezoelectric fiber material drive layer (1) is activated; in the burst acceleration mode, the piezoelectric fiber material drive layer (1) and the shape memory alloy drive layer (2) are activated simultaneously; in the emergency steering mode, the single-sided SMA spring array is contracted and the opposite side MFC patch brake is executed. The heating power of the SMA spring array and the vibration phase difference of the MFC patch are adjusted in real time to optimize propulsion efficiency.

6. The biomimetic fish-driving method according to claim 5, characterized in that, The sensors include a water flow sensor, an attitude sensor, and a position sensor, wherein: The water flow sensor is used to monitor the water flow velocity in real time; The attitude sensor is used to monitor the attitude of the bionic fish in real time. The position sensor is used to monitor the position of the bionic fish in real time.

7. The biomimetic fish driving method according to claim 5, characterized in that, The process of adjusting the heating power of the SMA spring array and the vibration phase difference of the MFC patch in real time is achieved through a closed-loop control system. This closed-loop control system automatically adjusts the heating power and vibration phase difference based on the information fed back by the sensor to ensure that the bionic fish can maintain optimal propulsion efficiency and stability under different water flow conditions and movement modes.

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