A triboelectric three-dimensional flow field sensor inspired by lateral line cuticular sensory papillae

Abstract

The application discloses a triboelectric three-dimensional flow field sensor inspired by lateral line cuticular sensory organ, which comprises a cylindrical shell, a signal analysis unit, a trigger unit and a plurality of triboelectric sensing units; the triboelectric sensing units are arranged in different spatial directions in a hollow cavity and comprise elastic reset parts and friction parts, and the two ends of the elastic reset parts are connected with the inner wall of the cylindrical shell and the friction parts, respectively; one end of the trigger unit is movably connected with the cylindrical shell, and the trigger unit applies force to the triboelectric sensing units after being disturbed by the flow field, so that the friction material layer is separated to generate an electric signal, and the signal analysis unit receives and analyzes the electric signal; the application can perceive the three-dimensional flow field in all directions and break through the limitation of two-dimensional perception; the mechanical energy-electric signal direct conversion is realized by relying on the triboelectric nanogenerator effect, the environmental adaptability is high, the high turbulence wake flow and the flow field change can be responded sensitively, multi-dimensional flow field data are provided for underwater environment monitoring, robot motion control and the like, and the application helps to accurately perceive the underwater complex three-dimensional flow field.

Description

Technical Field

[0001] This invention relates to the field of biomimetic sensors and marine exploration technology, and in particular to a triboelectric three-dimensional flow field sensor inspired by the lateral line epidermal neural tumulus. Background Technology

[0002] In underwater exploration, marine engineering, and robotic operations, accurate perception of flow fields and the motion state of the carrier is crucial for mission execution. Currently, mainstream technologies rely on acoustic and optical sensors, but both have significant limitations: acoustic equipment is expensive, susceptible to signal interference, and unstable in complex waters; optical equipment, on the other hand, heavily depends on water transparency, its sensing ability drops sharply in turbid or low-light environments, and it is difficult to operate stably in wake or high-particle waters. Summary of the Invention

[0003] This invention provides a triboelectric three-dimensional flow field sensor inspired by the lateral line epidermal nerve thalamus to overcome the above-mentioned technical problems.

[0004] To achieve the above objectives, the technical solution of the present invention is as follows: A triboelectric three-dimensional flow field sensor inspired by the lateral line epidermal neural thalamus is disposed on the surface of an underwater vehicle, comprising: a cylindrical shell with a hollow cavity inside, a signal analysis unit, a triggering unit, and several friction sensing units; the several friction sensing units are arranged in different spatial orientations within the hollow cavity and are each connected to the signal analysis unit via independent leads; each friction sensing unit includes an elastic reset part and a friction part composed of multiple friction material layers; one end of the elastic reset part is connected to the inner wall of the cylindrical shell, and the other end is connected to the friction part; One end of the trigger unit is movably connected to one end of the cylindrical shell and displaces in response to flow field disturbances, thereby driving the other end, which is located in the hollow cavity, to apply force to one or more friction sensing units, thereby triggering the contact separation of multiple friction material layers to generate electrical signals; the signal analysis unit is used to receive and analyze the electrical signals generated by each friction sensing unit to identify the parameters of the three-dimensional flow field and / or the motion state of the underwater vehicle; the elastic reset part is used to drive the trigger unit to return to the initial position by elastic restoring force after the flow field disturbance ends.

[0005] Furthermore, the plurality of friction sensing units include at least a first set of friction sensing units for sensing the flow field in the front, back, left, and right directions in the horizontal plane, and a second set of friction sensing units for sensing the flow field in the vertical direction.

[0006] Further, the friction part includes: a friction layer, a first encapsulation protection layer, a second encapsulation protection layer, and an overall encapsulation layer; the first encapsulation protection layer, the second encapsulation protection layer, and the overall encapsulation layer are sequentially sleeved on the outside of the friction layer; the friction layer includes a base electrode layer, a deformable electrode layer, and a dielectric friction layer; the base electrode layer, the deformable electrode layer, and the dielectric friction layer are sequentially stacked, and the deformable electrode layer is disposed opposite to the dielectric friction layer.

[0007] Furthermore, the triggering unit includes a hemispherical dome, an annular cylindrical flexible sealing sleeve, an elastic connecting rod, a first triggering part for triggering the first set of friction sensing units, and a second triggering part for triggering the second set of friction sensing units; the two ends of the flexible sealing sleeve are respectively sealed to the circumferential sidewall of the dome and the end of the cylindrical shell; a limiting groove is provided in the hollow cavity of the cylindrical shell; one end of the elastic connecting rod is fixed to the center of the dome, and the first triggering part and the second triggering part are arranged sequentially along the direction away from the dome, and the second triggering part is slidably engaged in the limiting groove.

[0008] Furthermore, the elastic reset part includes a plurality of spring posts; the inner wall of the cylindrical outer shell is provided with a plurality of spring post mounting slots, one end of the spring post is disposed in the spring post mounting slot, and the other end is fixedly connected to the overall encapsulation layer.

[0009] Furthermore, the substrate electrode layer is made of conductive fabric; The deformable electrode layer is made of conductive ink; The dielectric triboelectric layer is made of FEP film; The first encapsulation protective layer is made of CPP film; The second encapsulation protective layer is made of nitrile rubber; The overall encapsulation layer is made of silicone material.

[0010] Beneficial Effects: This invention, by arranging friction sensing units along different spatial orientations, enables omnidirectional perception of three-dimensional flow fields, accurately identifying flow field parameters and the motion state of underwater vehicles. It overcomes the limitations of traditional two-dimensional perception frameworks and can capture key flow field information of underwater vehicles. Utilizing the triboelectric nano-power generation effect, it directly converts the mechanical energy of the flow field into electrical signals without relying on external propagation media. It can operate stably in harsh underwater environments such as turbid waters and sonar blind spots, adapting to highly turbulent wakes caused by underwater vehicles or natural phenomena, and responding sensitively to changes in three-dimensional flow fields. This provides multi-dimensional flow field data support for underwater environmental monitoring, underwater robot motion control and navigation, and marine engineering flow field assessment, facilitating accurate perception of complex three-dimensional underwater flow fields and intelligent control of related carriers. Attached Figure Description

[0011] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0012] Figure 1 This is a schematic diagram of the triboelectric three-dimensional flow field sensor of the present invention after removing part of the outer shell; Figure 2 This is a diagram showing the positional sequence of the friction material layers inside the friction part in an embodiment of the present invention; Figure 3 This is a schematic diagram of the first structure of the triboelectric three-dimensional flow field sensor in this embodiment of the invention after removing part of the outer shell and the flexible sealing sleeve; Figure 4 This is a schematic diagram of the second structure of the triboelectric three-dimensional flow field sensor in an embodiment of the present invention after removing part of the outer shell and the flexible sealing sleeve; Figure 5 This is a schematic diagram of the trigger unit in an embodiment of the present invention; Figure 6 This is a schematic diagram of the cylindrical outer shell in an embodiment of the present invention.

[0013] In the picture: 1. Cylindrical outer shell; 11. Limiting groove; 12. Spring post mounting groove; 2. Trigger unit; 21. Dome; 22. Flexible sealing sleeve; 23. Elastic connecting rod; 24. First trigger part; 25. Second trigger part; 3. Friction sensing unit; 31. Elastic reset part; 32. Friction part; 321. Friction layer; 321a. Base electrode layer; 321b. Deformable electrode layer; 321c. Dielectric friction layer; 322. First encapsulation protection layer; 323. Second encapsulation protection layer. Detailed Implementation

[0014] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0015] The lateral line is a core organ for fish to perceive their underwater environment, playing a crucial role in water flow changes and spatial positioning. Fish use the lateral line to sense flow field information such as speed and direction, adjusting their swimming posture, avoiding obstacles, coordinating group movements, and precisely hunting. From a biomimetic perspective, current underwater flow field perception relies on acoustic and optical sensors, which suffer from high costs, maintenance difficulties, and limited application scenarios. The fish lateral line system offers a new approach to overcoming these bottlenecks. This system consists of surface neural humms (SN) and channel neural humms (CN), responsible for sensing changes in flow velocity and direction, as well as pressure gradients and acceleration, respectively. This enables fish to efficiently navigate, avoid obstacles, and cooperate even in dark or turbid environments.

[0016] These findings provide a basis for acquiring underwater flow field information and the motion status of related carriers through lateral line sensor feedback. This enables underwater equipment to achieve intelligent control using sensor signals, enhancing environmental adaptability, motion stability, and operational accuracy. Furthermore, combining this with triboelectric nanogenerator (TENG) technology can directly convert mechanical energy into electrical energy. This technology boasts advantages such as simple structure and strong environmental adaptability, effectively compensating for the shortcomings of traditional sensors. It provides a more reliable sensing method for underwater robot control, target recognition, and environmental monitoring, demonstrating significant technological value and application prospects.

[0017] Based on the above principles, this embodiment provides a triboelectric three-dimensional flow field sensor inspired by the lateral line epidermal neural thalamus, such as... Figure 1 As shown, the device is installed on the surface of an underwater vehicle and includes: a cylindrical outer shell 1 with a hollow cavity inside, a signal analysis unit, a triggering unit 2, and several friction sensing units 3; the several friction sensing units 3 are arranged in different spatial orientations in the hollow cavity and are connected to the signal analysis unit through independent leads; each friction sensing unit 3 includes an elastic reset part 31 and a friction part 32 composed of multiple friction material layers; one end of the elastic reset part 31 is connected to the inner wall of the cylindrical outer shell 1, and the other end is connected to the friction part 32; One end of the triggering unit 2 is movably connected to one end of the cylindrical shell 1 and is displaced in response to flow field disturbance, thereby driving the other end, which is located in the hollow cavity, to apply force to one or more friction sensing units 3, thereby triggering the contact separation of multiple friction material layers to generate an electrical signal. The signal analysis unit is used to receive and analyze the electrical signals generated by each friction sensing unit 3 in order to identify the parameters of the three-dimensional flow field and / or the motion state of the underwater vehicle. Specifically, multiple friction sensing units are connected to the signal analysis unit through independent leads. The connection points of each lead are located in a sealed electrical connection area and are encapsulated with silicone, epoxy resin or other potting materials. When the lead passes through the housing, it is led out through a waterproof lead holder or a sealed lead end, which ensures stable output of multi-channel signals while maintaining the overall sealing of the device.

[0018] The elastic reset part 31 is used to drive the trigger unit 2 to return to the initial position by elastic restoring force after the flow field disturbance ends.

[0019] Specifically, the sensor provided in this embodiment, which mimics the lateral line epidermal neural tumulus sensing mechanism of fish, can achieve all-round perception of the three-dimensional flow field by arranging friction sensing units 3 along different spatial orientations. It can accurately identify flow field parameters and the motion state of underwater vehicles, breaking through the limitations of the traditional two-dimensional sensing framework and capturing key flow field information of underwater vehicles. Relying on the triboelectric nano-power generation effect, the mechanical energy of the flow field is directly converted into electrical signals without relying on external propagation media. It can still work stably in harsh underwater environments such as turbid water and sonar blind spots, and has strong environmental adaptability. An elastic reset part 31 is provided so that the trigger unit 2 can be accurately driven after the flow field disturbance ends. Returning to the initial position avoids continuous pressure on the friction sensing unit 3 due to inertial offset or jamming of the components, ensuring that the starting position of each signal trigger is consistent, effectively eliminating residual interference, and improving the correspondence accuracy between electrical signals and flow field parameters, as well as the timeliness and accuracy of signal response; each friction sensing unit 3 is connected to the signal analysis unit through independent leads to form a multi-channel signal acquisition structure, which can realize differentiated capture and fusion analysis of flow field signals in different directions, further improving the accuracy of three-dimensional flow field perception.

[0020] Specifically, this embodiment features a compact overall structure and simple core component design. It eliminates the need for complex and precise acoustic transducers or optical imaging components, resulting in lower manufacturing costs and easy mounting on the surface of underwater vehicles, meeting lightweight application requirements. Flow field disturbances are transmitted to the friction sensing unit 3 only through the triggering unit 2. The friction material layer does not directly contact seawater, and the sealing design effectively avoids seawater corrosion and leakage, improving the sensor's operational stability and lifespan. It can sensitively respond to changes in flow velocity and flow direction in three-dimensional space, adapting to highly turbulent wakes caused by underwater vehicles or natural phenomena. This provides reliable sensing data for underwater vehicle navigation, obstacle avoidance, and motion control. Furthermore, multiple sensors can form a distributed monitoring network, solving the problem of limited sensing range of a single sensor. It is suitable for various underwater scenarios such as marine environmental monitoring and underwater robot operations. In a specific embodiment, the plurality of friction sensing units 3 include at least a first set of friction sensing units for sensing the flow field in the forward, backward, left, and right directions in the horizontal plane, and a second set of friction sensing units for sensing the flow field in the vertical direction.

[0021] Specifically, in this embodiment, preferably, four first-group friction sensing units and one second-group friction sensing unit are set up. Through the targeted layout of horizontal and vertical sensing units, three-dimensional capture of the underwater flow field is achieved, which makes up for the deficiency of only being able to identify the motion state in the horizontal plane. It can accurately capture key flow field information that determines the pitch attitude, depth change and vertical stability of the underwater vehicle. By sensing the horizontal and vertical flow fields separately, the sensing units in different directions can respond to the flow field disturbances in the corresponding directions and generate electrical signals with obvious spatial characteristics. This makes it easy for the signal analysis unit to quickly distinguish the spatial orientation of the incoming flow, improving the accuracy and efficiency of three-dimensional flow direction recognition. The signal analysis unit can quantitatively evaluate the pitch angle, vertical motion trend and other states of the vehicle through amplitude comparison and phase analysis of multi-dimensional signals. It can also effectively distinguish between external flow field disturbances and the vehicle's own active maneuvers, providing more comprehensive and accurate sensing data for the motion control of the underwater vehicle. Meanwhile, the multi-dimensional sensor unit layout is adapted to the real complex three-dimensional fluid environment underwater, and can adapt to different types of flow field changes such as horizontal flow, upflow, and bottom vortex, so as to realize the all-round perception of parameters such as flow velocity, flow direction, and pressure gradient of three-dimensional flow field, and improve the sensor's adaptability and perception performance in complex underwater environments.

[0022] In a specific embodiment, such as Figure 2 As shown, the friction part 32 includes: a friction layer 321, a first encapsulation protection layer 322, a second encapsulation protection layer 323, and an overall encapsulation layer; The friction layer 321 is sequentially covered with the first encapsulation protection layer 322, the second encapsulation protection layer 323, and the overall encapsulation layer. The friction layer 321 includes a base electrode layer 321a, a deformable electrode layer 321b, and a dielectric friction layer 321c. The base electrode layer 321a, the deformable electrode layer 321b, and the dielectric tribological layer 321c are stacked sequentially, with the deformable electrode layer 321b and the dielectric tribological layer 321c positioned opposite each other.

[0023] Specifically, in this embodiment, the friction layer 321 adopts a layered stacked structure of a base electrode layer 321a, a deformable electrode layer 321b, and a dielectric friction layer 321c. The deformable electrode layer 321b and the dielectric friction layer 321c are arranged opposite to each other. Under the disturbance of the flow field, they can achieve efficient contact separation movement, ensure the stable occurrence of the triboelectric effect, efficiently convert mechanical energy into electrical signals, and improve the power generation efficiency and signal output stability of the sensing unit. Specifically, the deformable electrode layer 321b is designed to adapt to the minute forces caused by flow field disturbances, and can undergo flexible deformation with external forces, enhancing the contact and adhesion with the dielectric friction layer 321c. At the same time, it can sense weak flow field changes, significantly improving the sensor's sensitivity to minute disturbances in the three-dimensional flow field. The friction layer 321 is surrounded by a multi-layer encapsulation protection structure, which is stacked sequentially to form multiple protective barriers, effectively isolating external corrosive media and preventing corrosion and damage to the friction layer electrodes and friction materials. This ensures the integrity and operational stability of the internal structure of the friction layer and extends the service life of the sensing unit. The overall encapsulation layer provides final shaping and sealing for the multi-layer structure, further improving the overall sealing performance of the friction part. This ensures that the friction layer 321 is always in a dry working environment, avoiding problems such as leakage and signal failure caused by water ingress, and ensuring the continuous and reliable operation of the friction sensing unit in complex underwater environments.

[0024] Specifically, the combination design of the multi-layer encapsulation protective layer and the overall encapsulation layer can not only provide physical protection for the friction layer and buffer the direct impact of external forces on the friction layer, but also maintain the structural shape of the friction layer and prevent it from undergoing irreversible deformation due to external extrusion and collision, thus ensuring the accuracy of contact separation movement.

[0025] In a specific embodiment, the substrate electrode layer 321a is made of a conductive fabric material; The deformable electrode layer 321b is made of conductive ink; The dielectric friction layer 321c is made of FEP film (fluorinated ethylene propylene copolymer film), but other insulating materials can also be used in practice; The first encapsulation protective layer 322 is made of CPP film (cast polypropylene film); The second encapsulation protective layer 323 is made of nitrile rubber; The overall encapsulation layer is made of silicone material.

[0026] Specifically, in this embodiment, the base electrode layer 321a is made of conductive fabric, which possesses good conductivity and structural flexibility. It can stably transmit the electrical signals generated by friction and adapt to minute deformations under flow field disturbances, forming a flexible fit with the deformable electrode layer 321b to ensure the overall deformation response capability of the friction layer. The deformable electrode layer 321b uses conductive ink and undergoes micro / nano structure processing. The conductive ink is soft and easily processed into micro / nano structures, significantly increasing the contact area with the dielectric friction layer 321c, enhancing the triboelectric effect, and simultaneously conducting... The electro-ink has stable conductivity, which can ensure efficient charge transmission and improve the strength and stability of the electrical signal output. The dielectric triboelectric layer 321c uses FEP film, which is a high-quality dielectric material for triboelectric power generation. FEP film has good chemical stability, water resistance and corrosion resistance, and is suitable for harsh underwater working environments. In addition, the surface of the FEP film is micro-nano treated in this embodiment to further improve the sensing sensitivity. At the same time, FEP film has strong electronegativity. During the contact process, the surface of FEP film is negatively charged and the ink electrode is positively charged. The micro-nano structure surfaces are squeezed together to generate significant charge transfer.

[0027] Specifically, the first encapsulation protective layer 322 is made of CPP film, which is thin and lightweight and has good moisture-proof and scratch-proof properties. It can provide lightweight basic protection for the friction layer 321 without increasing the volume of the friction part. At the same time, it can reduce the wear of the friction layer 321 by external friction and maintain the integrity of the surface structure of the friction layer. The second encapsulation protective layer 323 is made of nitrile rubber, which has excellent oil resistance, water resistance, corrosion resistance and elastic buffering properties. It can also buffer the mechanical impact caused by flow field disturbance, avoid damage to the internal friction layer structure by hard impact, and improve the anti-interference ability of the friction part. The overall encapsulation layer is made of silicone material. Silicone has excellent underwater sealing, corrosion resistance and biocompatibility, which is suitable for the working environment of underwater vehicles. It can form the final sealing and shaping protection for the friction part, ensuring that the internal structure does not get water ingress or loosen. At the same time, the flexibility of silicone can adapt to the small deformation of the friction part without affecting the contact and separation movement of the friction layer, taking into account both sealing performance and sensing response.

[0028] The conductive fabric, conductive ink, FEP film, CPP film, nitrile rubber, and silicone selected in this embodiment are all mature industrial materials that are readily available and cost-controllable, facilitating mass processing and production of sensors and effectively reducing overall manufacturing costs.

[0029] Specifically, the signal analysis unit analyzes the sensed electrical signals and derives the motion state of the underwater vehicle using the following method: When the underwater vehicle is stationary, the conductive ink and the FEP film will not come into contact or separate, so no induced charge is generated. The underwater vehicle is stationary, and the voltage signal analysis shows that the underwater vehicle is stationary. When the triboelectric three-dimensional flow field sensor moves with the underwater vehicle under the action of the flow field, a regular voltage signal is generated between the conductive ink and the FEP film. When the flow field acting on an underwater vehicle is symmetrical, the voltage signal amplitude is consistent. By analyzing the voltage signal, it can be determined that the underwater vehicle is in a stable forward state. When the underwater vehicle tilts its nose down to begin its descent, the friction sensor unit located at the bottom will be the first to detect the change in the angle of attack of the flow field. The amplitude and frequency characteristics of its output signal not only indicate the trend of the descent, but also quantitatively assess the pitch angle by comparing the phase with the horizontal signal. When encountering upwelling or bottom vortices, the signal characteristics of the friction sensor unit can be used to effectively distinguish whether it is caused by external flow field disturbances or the active maneuvering of the vehicle itself.

[0030] Specifically, the method by which the signal analysis unit analyzes the sensed electrical signals and determines the direction of the underwater flow field is as follows: when the underwater vehicle is approached from the left, the peak density of the electrical signal generated by the friction sensing unit in the corresponding direction increases; when the underwater vehicle is approached from the right, the peak density of the electrical signal generated by the friction sensing unit in the corresponding direction increases.

[0031] In a specific embodiment, such as Figures 3-5 As shown, the triggering unit 2 includes a dome 21 with a hemispherical structure, a flexible sealing sleeve 22 in the shape of an annular cylinder, an elastic connecting rod 23, a first triggering part 24 for triggering the first group of friction sensing units, and a second triggering part 25 for triggering the second group of friction sensing units; The two ends of the flexible sealing sleeve 22 are respectively sealed to the circumferential sidewall of the dome 21 and the end of the cylindrical outer shell 1; like Figure 6 As shown, a limiting groove 11 is provided in the hollow cavity of the cylindrical outer shell 1; One end of the elastic connecting rod 23 is fixed to the center of the dome 21, and the first trigger part 24 and the second trigger part 25 are sequentially sleeved on the rod body in the direction away from the dome 21, and the second trigger part 25 is slidably locked in the limiting groove 11.

[0032] Specifically, in this embodiment, the dome adopts a hemispherical structure, which can efficiently converge and transform the impact force of the flow field from any direction in three-dimensional space into directional mechanical displacement. There are no dead angles in the flow field force, ensuring that the sensor can respond sensitively to flow field disturbances in different directions, improving the comprehensiveness of three-dimensional flow field perception. The fixed connection between the dome 21, the elastic connecting rod 23 and the two triggering parts can realize the efficient transmission of mechanical energy of the flow field, reduce energy loss, and ensure that even weak flow field disturbances can drive the friction sensing unit to generate effective electrical signals, improving the sensor's sensing sensitivity. The dome 21 and the cylindrical shell 1 are sealed together by the flexible sealing sleeve 22, which not only ensures the sealing performance of the hollow cavity inside the device, preventing corrosion and leakage of internal components caused by seawater and moisture, but also has flexible characteristics, not restricting the normal displacement of the dome 21 after being disturbed by the flow field, and at the same time can provide flexible guidance for the dome 21 to assist its reset. Specifically, a partition is provided in the middle of the hollow cavity of the cylindrical shell 1, and a limiting groove 11 is provided on the partition near the second trigger part 25.

[0033] Specifically, in this embodiment, the first trigger part 24 is a cylindrical structure, the second trigger part 25 is a spherical structure, and an initial safety gap is provided between the second trigger part 25 and the bottom friction sensing unit to avoid accidental contact of the device under conditions of no external flow field or weak disturbance.

[0034] Specifically, the elastic connecting rod 23 is made of carbon fiber material. In conjunction with the layered first and second triggering parts, it can selectively trigger two sets of friction sensing units in the horizontal and vertical directions to realize the multi-dimensional transmission of flow field disturbances. This allows flow field signals in different directions to be accurately matched to dedicated sensing units, avoiding signal cross-interference and improving the accuracy of flow field direction recognition. Furthermore, due to the elasticity of the elastic connecting rod itself, it can form a double reset cooperation with the elastic reset part 31. After the flow field disturbance ends, it helps drive the triggering unit to quickly return to its initial position. At the same time, it can buffer the instantaneous strong impact force of the flow field, reduce mechanical damage to the internal sensing units, and improve the service life of the triggering unit 2 and the friction sensing unit 3. Specifically, such as Figure 6 As shown, in this embodiment, a limiting groove 11 is provided inside the cylindrical outer shell 1, and the second trigger part 25 is slidably locked in the groove, which can form a precise radial limit and axial guide for the movement of the trigger unit 2, prevent the trigger unit 2 from being deviated or stuck due to the impact force of the flow field, ensure that it always moves along the preset trajectory, ensure the accuracy of the working position of the first and second trigger parts and the friction sensing unit 3, and avoid sensing errors caused by structural deviation. Specifically, the first and second triggering parts are arranged sequentially along the elastic connecting rod 23 to adapt to the spatial layout of the horizontal and vertical sensing units, making the spatial matching degree between the triggering structure and the sensing structure higher, the overall structural layout more compact, effectively utilizing the hollow cavity space inside the cylindrical shell, which is conducive to the miniaturization and lightweight design of the sensor, and easy to mount on the surface of underwater vehicles.

[0035] In a specific embodiment, the elastic reset part 31 includes a plurality of spring posts; like Figure 5 As shown, the inner wall of the cylindrical outer shell 1 is provided with a plurality of spring post mounting slots 12. One end of the spring post is disposed in the spring post mounting slot 12, and the other end is fixedly connected to the overall encapsulation layer.

[0036] Specifically, each elastic reset part 31 consists of four spring pillars, which can provide uniform elastic support and reset force to the friction part from multiple directions, ensuring that the friction part can quickly and smoothly return to its initial position after the flow field disturbance disappears, avoiding reset offset and jamming problems caused by single-point support, and improving reset accuracy; one end of the spring pillar is fixed in the spring pillar mounting groove 12 on the inner wall of the cylindrical shell 1, and the other end is connected to the overall encapsulation layer of the friction part. The connection structure is stable and the force is transmitted directly, which can efficiently convert the deformation force brought by the flow field disturbance into the elastic potential energy of the spring pillar. After the disturbance ends, the elastic potential energy can be released quickly, driving the friction part and the trigger unit to reset synchronously, ensuring that the friction part 32 can restore the initial sensing state in time and eliminate signal residual interference; Specifically, the inner wall of the cylindrical shell 1 has multiple spring post mounting slots 12, which provide a dedicated fixing and positioning structure for the spring posts. This ensures that the multiple spring posts are evenly distributed in the circumferential and radial directions, so that the friction part 32 is subjected to balanced load and avoids deformation of the friction layer structure and contact separation failure caused by excessive local stress. At the same time, the cooperative design of the spring posts and the spring post mounting slots 12 allows the overall structure of the elastic reset part 31 to be highly integrated with the cylindrical shell 1 and the friction part, making full use of the internal space of the shell without occupying additional effective layout space of the sensor. This is conducive to the miniaturization and compact design of the sensor and adapts to the mounting requirements of the surface of underwater vehicles. Specifically, the spring column has a simple structure and fast response speed, which can adapt to rapid changes in flow field disturbances. Whether it is high-frequency flow field fluctuations or gradually changing flow field trends, it can make timely elastic responses and reset actions, ensuring that the sensor can perceive changes in the three-dimensional flow field in real time and improve the timeliness of signal response. The elastic support of multiple spring columns can form a flexible buffer for the friction sensing unit. When the flow field generates instantaneous strong impact force, the spring column can absorb part of the mechanical energy through its own compression, reducing the mechanical damage of the impact force to the friction part and the triggering unit, and improving the impact resistance and service life of the sensor's core components.

[0037] Specifically, in this embodiment, relevant components, such as the cylindrical shell, can be manufactured using 3D printing technology to ensure structural accuracy and the realization of complex shapes, and to meet the structural adaptability requirements of three-dimensional perception.

[0038] Specifically, this embodiment establishes two types of experimental platforms to verify the performance of three-dimensional flow field sensing and optimize parameters: First, a land-based multi-dimensional motion experimental platform equipped with a computer, multi-degree-of-freedom linear motor, high-resistance electrometer, and pressure sensor to simulate motion states in different directions and angles within three-dimensional space, testing the electrical signal output characteristics of the sensors under different material and structural parameters; second, a three-dimensional steady-state flow field experimental platform, constructing an adjustable horizontal, vertical, and oblique water flow simulation environment to test the device's response performance under different combinations of flow velocity and direction in different dimensions. In the signal analysis and characteristic exploration phase, the signal analysis unit extracts and fuses three-dimensional features from the electrical signals of multiple friction sensing units, focusing on capturing the amplitude differences, phase relationships, and frequency distributions of electrical signals in different spatial orientations. The signal analysis unit analyzes the sensed electrical signals and derives three-dimensional flow field information and related carrier motion states as follows: In the wake scenario, the phase difference can be combined to estimate the angle of the dominant incoming flow; the main peak of the spectrum corresponds to the typical vortex shedding frequency, used to characterize wake instability. A correlation model is established with the three-dimensional flow field parameters and the carrier motion state. For example, under the influence of flow fields in different directions, the amplitude of the electrical signal of the corresponding friction sensing unit varies. By comparing the signal amplitudes in each direction, the dominant flow field direction can be determined. The signal frequency change is related to the flow field disturbance frequency and can reflect the flow field stability. Through long-term operation testing, the durability and stability of the sensor in complex three-dimensional flow fields are explored to ensure that the device can continuously and reliably capture multi-dimensional flow field changes. Ultimately, this will form a system that can capture three-dimensional flow field signals in three dimensions and convert them into differentiated electrical signals, meeting the sensing needs of complex three-dimensional underwater environments.

[0039] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A triboelectric three-dimensional flow field sensor inspired by the lateral line epidermal nerve thalamus, characterized in that, The device is installed on the surface of an underwater vehicle and includes: a cylindrical shell (1) with a hollow cavity inside, a signal analysis unit, a triggering unit (2) and several friction sensing units (3). Several friction sensing units (3) are arranged in different spatial orientations within the hollow cavity and are connected to the signal analysis unit via independent leads; each friction sensing unit (3) includes an elastic reset part (31) and a friction part (32) composed of multiple friction material layers. One end of the elastic reset part (31) is connected to the inner wall of the cylindrical shell (1), and the other end is connected to the friction part (32); One end of the triggering unit (2) is movably connected to one end of the cylindrical shell (1) and generates displacement in response to flow field disturbance, thereby driving the other end set in the hollow cavity to apply force to one or more friction sensing units (3), thereby triggering multiple friction material layers to contact and separate to generate electrical signals. The plurality of friction sensing units (3) include at least a first set of friction sensing units for sensing the flow field in the front, back, left and right directions in the horizontal plane, and a second set of friction sensing units for sensing the flow field in the vertical direction. The triggering unit (2) includes a dome (21) with a hemispherical structure, a flexible sealing sleeve (22) with an annular cylindrical shape, an elastic connecting rod (23), a first triggering part (24) for triggering the first set of friction sensing units, and a second triggering part (25) for triggering the second set of friction sensing units. The two ends of the flexible sealing sleeve (22) are respectively sealed to the circumferential sidewall of the dome (21) and the end of the cylindrical shell (1); The cylindrical outer shell (1) has a limiting groove (11) in its hollow cavity. One end of the elastic connecting rod (23) is fixed to the center of the dome (21), and the rod body is provided with the first trigger part (24) and the second trigger part (25) in sequence along the direction away from the dome (21), and the second trigger part (25) is slidably locked in the limiting groove (11); The signal analysis unit is used to receive and analyze the electrical signals generated by each friction sensing unit (3) to identify the parameters of the three-dimensional flow field and / or the motion state of the underwater vehicle. The elastic reset part (31) is used to drive the trigger unit (2) to return to the initial position by elastic restoring force after the flow field disturbance ends.

2. The triboelectric three-dimensional flow field sensor inspired by the lateral line epidermal nerve thalamus according to claim 1, characterized in that, The friction part (32) includes: a friction layer (321), a first encapsulation protection layer (322), a second encapsulation protection layer (323), and an overall encapsulation layer; The friction layer (321) is sequentially covered with the first encapsulation protection layer (322), the second encapsulation protection layer (323), and the overall encapsulation layer; The friction layer (321) includes a base electrode layer (321a), a deformable electrode layer (321b), and a dielectric friction layer (321c). The base electrode layer (321a), the deformable electrode layer (321b), and the dielectric tribological layer (321c) are stacked sequentially, with the deformable electrode layer (321b) and the dielectric tribological layer (321c) positioned opposite each other.

3. The triboelectric three-dimensional flow field sensor inspired by the lateral line epidermal nerve thalamus according to claim 2, characterized in that, The elastic reset part (31) includes a plurality of spring posts; The inner wall of the cylindrical shell (1) is provided with a plurality of spring post mounting slots (12). One end of the spring post is set in the spring post mounting slot (12), and the other end is fixedly connected to the overall encapsulation layer.

4. The triboelectric three-dimensional flow field sensor inspired by the lateral line epidermal nerve thalamus according to claim 2, characterized in that, The substrate electrode layer (321a) is made of conductive fabric; The deformable electrode layer (321b) is made of conductive ink; The dielectric triboelectric layer (321c) is made of FEP film; The first encapsulation protective layer (322) is made of CPP film; The second encapsulation protective layer (323) is made of nitrile rubber; The overall encapsulation layer is made of silicone material.

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