Information transmission device and method based on film-coated bionic fish tail motion modulation

Abstract

The application relates to the field of underwater robots and discloses an information transmission device and method based on film bionic fish tail motion modulation, which comprises a film bionic fish tail assembly, a control unit and a driving mechanism; an optical response film layer arranged on the surface of the bionic fish tail is used to generate distinguishable and repeatable brightness changes, color changes, flicker changes or pattern changes under the conditions of fish tail swing, overall azimuth angle change, light direction change and observation direction change; and the above dynamic visual response is modulated through preset motion control parameters, so that the dynamic visual response is corresponded to the information to be transmitted, thereby realizing the coding, transmission and identification of specific information. The application realizes the multiplexing of motion functions and information transmission functions and reduces the demand for additional communication hardware and active light-emitting devices.

Description

Technical Field

[0001] This invention relates to the field of underwater robots, and more particularly to an information transmission device and method based on the modulation of biomimetic fish tail motion with a membrane. Background Technology

[0002] With the development of underwater robots, biomimetic robotic fish, and marine observation equipment, the demand for underwater close-range information interaction, group collaborative identification, status prompts, and task identification is increasing.

[0003] For biomimetic robotic fish, propulsion and maneuvering typically rely on the periodic movements of flexible components such as the tail, pectoral fins, or undulating fins. Existing technologies mostly use these flexible components as propulsion, steering, or biomimetic shape parts, focusing on their hydrodynamic performance, motion stability, and structural reliability, while rarely using them as functional carriers for information modulation and transmission. In other words, the tail movements of existing biomimetic robotic fish usually only serve a motion control function, failing to fully utilize their controllable motion characteristics such as periodic oscillations, amplitude variations, frequency changes, and azimuth angle variations to carry and transmit specific information.

[0004] On the other hand, existing color-changing films, pearlescent films, structural color films, interference films, or other coating materials with angle-dependent optical responses are typically used in packaging, decoration, anti-counterfeiting, display, or static labeling. Although these materials can exhibit changes in brightness, color, or texture under different viewing angles or lighting angles, their applications are mostly limited to static display or passive decoration. They are not systematically coupled with the periodic movements of flexible moving parts such as bionic fish tails, nor have they formed control methods for information encoding, modulation, and recognition.

[0005] If the above-mentioned coating material is simply attached to the surface of the bionic fish tail, the following problems still exist: 1. The coating layer is usually only used as an appearance layer or decorative layer. Its brightness, color or pattern changes do not establish a clear correspondence with the information to be transmitted, and cannot achieve stable information encoding. 2. The existing motion parameters of bionic fish tails, such as swing frequency, swing amplitude, swing center angle, and overall azimuth angle, are usually only used for propulsion control and lack coding rules to convert motion parameters into visual information sequences; 3. Existing technologies lack structural schemes and control processes for modulating the optical response of the coating using the fish tail's own motion, making it difficult to achieve low-power visual information transmission without adding active light-emitting devices; 4. In underwater close-range identification or multi-robot collaborative scenarios, existing technologies struggle to transmit identity, status, instructions, or task information to external visual receivers through the bionic robot's own external surface and motion state. 5. Existing visual cues often rely on additional lights, displays, or electronic communication modules, which not only increases structural complexity, sealing difficulty, and energy consumption, but may also affect the low-disturbance characteristics and integrated shape design of biomimetic robotic fish; 6. Existing fishtail-driven structures typically focus only on a single degree of freedom of oscillation, lacking coordinated control between overall azimuth adjustment and fishtail oscillation, making it difficult to form a distinguishable, repeatable, and decodeable dynamic visual response under different viewing directions; 7. Existing systems lack a process for acquiring, recording, and decoding this type of dynamic visual information, making it difficult to convert changes in brightness, color, flicker frequency, or pattern caused by fish tail movement into recognizable information.

[0006] Therefore, it is necessary to propose a new technical solution that combines the controllable motion of a biomimetic fish tail, the angle-dependent optical response of the coating layer, and information encoding rules, enabling the fish tail to transmit specific information through its surface dynamic visual response while performing swinging motions. This solution should not be limited to a specific coating material, but should focus on solving the problem of how to utilize the motion modulation characteristics of the coated biomimetic fish tail to achieve information encoding, transmission, and recognition, thereby providing a new technical path for low-power, low-disturbance, short-range visual communication and group collaborative recognition of underwater biomimetic robots. Summary of the Invention

[0007] The purpose of this invention is to provide an information transmission device and method based on the motion modulation of a membrane-coated bionic fish tail, which solves the problems of existing underwater bionic robots that rely on active light-emitting devices, acoustic communication modules or other independent communication devices in close-range status prompting, identity recognition, task information transmission and group collaborative interaction, resulting in complex structure, increased power consumption, increased sealing difficulty, decreased low-disturbance characteristics and single information expression methods.

[0008] An information transmission device based on membrane-coated biomimetic fishtail motion modulation includes: A coated biomimetic fish tail component, the coated biomimetic fish tail component comprising a flexible fish tail substrate and an optically responsive coating layer disposed on at least one side of the surface of the flexible fish tail substrate; The control unit internally stores the correspondence between information to be transmitted and motion coding instructions. The control unit is used to acquire the information to be transmitted and generate the corresponding motion coding instructions according to the correspondence. A drive mechanism, the control end of which is connected to the control unit, and the power output end of which is connected to the flexible fishtail substrate; the drive mechanism is used to drive the membrane-coated bionic fishtail component to perform a preset spatial movement according to the motion coding instructions; The optically responsive coating layer performs the spatial motion synchronously with the flexible fishtail substrate, changing the light-receiving angle and spatial posture of the surface of the optically responsive coating layer relative to the external illumination direction and the observation direction, and outputting a dynamic visual response sequence modulated by the motion coding command.

[0009] This invention also relates to an information transmission method based on the modulation of bionic fish tail motion with a coating, applied to the aforementioned information transmission device based on the modulation of bionic fish tail motion with a coating, comprising the following steps: Step S1: Configure the correspondence between the information to be transmitted and the motion coding instructions in the control unit; Step S2: The control unit acquires the input information to be transmitted and generates the corresponding motion coding instruction according to the correspondence. Step S3: The drive mechanism receives the motion coding instruction sent by the control unit, and drives the coated bionic fish tail assembly, which includes a flexible fish tail substrate and an optically responsive coating layer, to perform corresponding spatial movements according to the motion coding instruction. Step S4: The optical response coating layer moves synchronously with the flexible fishtail substrate in space, generating changes in relative spatial posture and light-receiving angle, and outputting a dynamic visual response sequence corresponding to the information to be transmitted. Step S5: The visual receiving and decoding unit acquires the dynamic visual response sequence and converts the extracted sequence features into the information to be transmitted according to the preset decoding rules.

[0010] The present invention also relates to a bionic robot with visual information transmission function, including a robot body and an information transmission device based on the motion modulation of a membrane-covered bionic fish tail mounted on the robot body. The membrane-covered bionic fish tail component of the information transmission device is disposed on the outer surface of the robot body, and the outer contour of the membrane-covered bionic fish tail component is in the shape of a bionic tail fin, pectoral fin, dorsal fin, pelvic fin or wave fin. The drive mechanism and the control unit of the information transmission device are located in the internal space of the robot body. The power output end of the drive mechanism passes through the sealed shell of the robot body and is mechanically connected to the root of the membrane bionic fish tail assembly. The control unit is communicatively connected to the main control module of the robot body and is used to receive identity features, status data, interaction instructions or synchronization signals issued by the main control module as input to the information to be transmitted in the corresponding relationship.

[0011] Compared with the prior art, the beneficial effects of the present invention are as follows: Existing biomimetic robotic fish tails are primarily used for propulsion, steering, or display, and their motion parameters typically only serve motion control. This invention utilizes the tail's controllable oscillation frequency, amplitude, center angle, overall azimuth, duration, and pause time—all motion parameters—to modulate the dynamic visual response generated by the coating layer. This allows the tail to transmit specific information such as identity, status, task, or instructions while performing its oscillation motion. Thus, the tail is no longer merely a propulsion or aesthetic component, but a composite functional component combining motion and information transmission capabilities.

[0012] Existing underwater visual cues or short-range communication methods typically require LEDs, displays, optical communication modules, acoustic communication modules, or other independent communication devices, which can easily increase system power consumption, sealing difficulty, wiring complexity, and structural volume. This invention, by controlling the movement of a coated biomimetic fish tail, enables the optical response of its surface to form a recognizable sequence of visual information. This allows for the transmission of specific information without the need for additional active light-emitting devices, thereby reducing system complexity and energy consumption.

[0013] In scenarios such as ecological observation, close-range observation, group collaboration, and underwater display, additional lighting, acoustic communication, or strong active signals may interfere with the environment or the target. This invention mainly utilizes the passive optical response changes caused by the movement of the fish's tail to express information. It does not require continuous active light emission or the generation of additional significant acoustic signals, thus helping to maintain the characteristics of low noise, low disturbance, and integrated shape of the biomimetic robotic fish.

[0014] Existing methods of attaching coating materials to the surface of moving parts typically only produce random or subjectively observed changes in brightness and color, making them unsuitable for stable information transmission. This invention, through preset encoding rules, converts the information to be transmitted into motion-coded instructions such as swing frequency, swing amplitude, overall azimuth angle, swing waveform, duration, and pause time. This establishes a clear correspondence between the fishtail movement and the dynamic visual response, thereby improving the certainty and decodeability of information expression.

[0015] This invention can not only use a single motion parameter for encoding, such as using different oscillation frequencies or amplitudes to represent different information symbols; it can also use multi-parameter combination encoding, such as combining oscillation frequency, oscillation amplitude, overall azimuth angle, and duration to form more distinguishable information states. By combining multi-dimensional motion parameters with the optical response of the coating, this invention can expand the information capacity and improve the distinguishability between different information symbols.

[0016] In a preferred embodiment, the present invention includes a first driving mechanism for adjusting the overall azimuth angle of the coated biomimetic fishtail assembly, and a second driving mechanism for driving the fishtail to oscillate periodically. Through the coordinated control of the overall azimuth angle adjustment and the fishtail oscillation, the attitude relationship of the coating layer relative to the viewing direction and the illumination direction can be changed, allowing the same fishtail to produce different dynamic visual response sequences under different encoded commands. Compared to fishtail structures with only a single degree of freedom of oscillation, the present invention more easily forms distinguishable and repeatable visual information expressions.

[0017] The dynamic visual response of this invention can manifest as changes in brightness, color, flicker frequency, color switching sequence, pattern changes, or spatial brightness distribution. The visual receiver can acquire these responses using a camera, photoelectric sensor, color sensor, or polarization vision sensor, and decode them using methods such as brightness extraction, color recognition, frequency analysis, and timing recognition. This method has good compatibility with existing visual perception devices and is easy to implement in robot vision systems, experimental camera systems, or external observation systems.

[0018] The biomimetic fish tail assembly, clamping and fixing structure, drive mechanism, and control unit used in this invention can all be modified and integrated based on existing biomimetic robotic fish tail structures. For biomimetic robots with existing fish tail swinging mechanisms, information transmission functions can be achieved by adding an optical response coating layer, adjusting the control program, and establishing coding rules, without significantly altering the overall robot structure, thus exhibiting good engineering adaptability.

[0019] This invention can convert information such as identification number, motion status, task status, synchronization signal or simple command into dynamic visual response sequence. It is applicable to close-range recognition between bionic robotic fish, visual recognition of the mother platform to the child platform in a mother-child bionic submersible, status prompts in underwater group collaboration, and non-active light emission information expression in low-disturbance observation scenarios.

[0020] Existing underwater communication methods typically involve trade-offs between transmission distance, power consumption, equipment complexity, environmental adaptability, and low disturbance. This invention utilizes the coupling relationship between the biomimetic fish tail's own motion and the optical response of its surface coating to transform the mechanical motion process into a coded, transmittable, and identifiable sequence of visual information, providing a new technical approach for short-range, low-power, and low-complexity underwater information transmission. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the information transmission device based on the modulation of fish tail motion using a membrane-coated biomimetic fish tail according to the present invention.

[0022] Figure 2 This is a schematic diagram of the information transmission method based on the modulation of biomimetic fish tail motion using a membrane coating, according to the present invention. Detailed Implementation

[0023] The terms “first,” “second,” “third,” “fourth,” etc. (if present) in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms “comprising” or “having,” and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0024] The purpose of this invention is to provide an information transmission device and method based on the motion modulation of a membrane-coated biomimetic fish tail, which solves the problems of existing underwater biomimetic robots relying on active light-emitting devices, acoustic communication modules or other independent communication devices in close-range status prompting, identity recognition, task information transmission and group collaborative interaction, resulting in complex structure, increased power consumption, increased sealing difficulty, decreased low-disturbance characteristics and single information expression mode.

[0025] This invention utilizes an optical response coating layer applied to the surface of a biomimetic fish tail to generate distinguishable and repeatable changes in brightness, color, flickering, or pattern under conditions such as tail swaying, overall azimuth angle changes, lighting direction changes, and observation direction changes. The dynamic visual response is modulated by preset motion control parameters to establish a correspondence between the response and the information to be transmitted, thereby enabling the encoding, transmission, and recognition of specific information.

[0026] Through the above methods, the present invention enables the bionic fish tail to not only perform propulsion, swinging, or display functions, but also to be used as a carrier of visual information transmission, realizing the reuse of motion functions and information transmission functions, reducing the need for additional communication hardware and active light-emitting devices, and is suitable for application scenarios such as underwater bionic robots, underwater group collaborative systems, mother-child bionic submersibles, low-disturbance observation platforms, and underwater experimental display systems.

[0027] like Figure 1 An information transmission device based on membrane-coated biomimetic fishtail motion modulation, comprising: A coated biomimetic fish tail component, the coated biomimetic fish tail component comprising a flexible fish tail substrate and an optically responsive coating layer disposed on at least one side of the surface of the flexible fish tail substrate; The control unit internally stores the correspondence between information to be transmitted and motion coding instructions. The control unit is used to acquire the information to be transmitted and generate the corresponding motion coding instructions according to the correspondence. A drive mechanism, the control end of which is connected to the control unit, and the power output end of which is connected to the flexible fishtail substrate; the drive mechanism is used to drive the membrane-coated bionic fishtail component to perform a preset spatial movement according to the motion coding instructions; The optically responsive coating layer performs the spatial motion synchronously with the flexible fishtail substrate, changing the light-receiving angle and spatial posture of the surface of the optically responsive coating layer relative to the external illumination direction and the observation direction, and outputting a dynamic visual response sequence modulated by the motion coding command.

[0028] The motion coding instruction includes at least one of the following parameters: swing frequency, swing amplitude, swing center angle, overall azimuth angle, swing waveform, duration of a single coding unit, pause time between adjacent coding units, and number of repetitions of the coding sequence. The optically responsive coating is at least one of the following: structural color film, pearlescent film, interference film, multilayer composite optical film, reflective film, and polarization-responsive film. The dynamic visual response sequence includes at least one of the following: brightness change sequence, color change sequence, flicker frequency change sequence, color switching sequence, pattern change sequence, and spatial brightness distribution change sequence.

[0029] The membrane-coated bionic fishtail assembly also includes an installation connection area located at the root of the flexible fishtail substrate, and a clamping and fixing structure fitted to the installation connection area. The clamping and fixing structure includes a first clamping member, a second clamping member, and a fastener. The mounting connection area of ​​the flexible fishtail substrate is disposed between the first clamping member and the second clamping member, and is fastened together by the fastener. The optically responsive coating layer is disposed on the main display area of ​​the flexible fishtail substrate other than the mounting connection area, or the optically responsive coating layer is in a void, disconnected or thinned structure in the mounting connection area between the first clamping member and the second clamping member.

[0030] The driving mechanism includes a first driving mechanism, a support structure, and a second driving mechanism; The power output end of the first driving mechanism is connected to the support structure and is used to drive the support structure to rotate around the first axis; The second drive mechanism is disposed on the support structure, and the power output end of the second drive mechanism is connected to the root of the membrane bionic fish tail component, for driving the membrane bionic fish tail component to reciprocate around the second axis.

[0031] The device also includes a visual receiving and decoding unit; The visual receiving and decoding unit includes an image acquisition module and a decoding module; The image acquisition module's acquisition end faces the coated bionic fishtail component, and is used to acquire continuous temporal images of the optical response coating layer during the spatial motion process; The decoding module stores a preset decoding rule table. The decoding module is used to extract the visual feature sequence of the optical response coating layer in the continuous time-series images, and perform mapping and comparison in the preset decoding rule table to convert it into the corresponding information to be transmitted.

[0032] In this invention, such as Figure 2 A method for information transmission based on the modulation of biomimetic fish tail motion with a membrane, comprising the following steps: Step S1: Configure the correspondence between the information to be transmitted and the motion coding instructions in the control unit; Step S2: The control unit acquires the input information to be transmitted and generates the corresponding motion coding instruction according to the correspondence. Step S3: The drive mechanism receives the motion coding instruction sent by the control unit, and drives the coated bionic fish tail assembly, which includes a flexible fish tail substrate and an optically responsive coating layer, to perform corresponding spatial movements according to the motion coding instruction. Step S4: The optical response coating layer moves synchronously with the flexible fishtail substrate in space, generating changes in relative spatial posture and light-receiving angle, and outputting a dynamic visual response sequence corresponding to the information to be transmitted. Step S5: The visual receiving and decoding unit acquires the dynamic visual response sequence and converts the extracted sequence features into the information to be transmitted according to the preset decoding rules.

[0033] In step S2, the correspondence includes at least one of single-parameter encoding rules and multi-parameter combination encoding rules; The single-parameter encoding rule includes mapping different contents of the information to be transmitted to a single swing frequency or a single swing amplitude of different values. The multi-parameter combination encoding rule includes mapping the information to be transmitted with different contents into a specific time sequence composed of two or more parameters among swing frequency, swing amplitude, overall azimuth angle and duration.

[0034] Step S5 includes: Acquire continuous time-series images of the membrane-coated bionic fishtail component during its movement; The average brightness, maximum brightness, hue value, saturation value, or spatial distribution parameters of the optical response coating layer region in the continuous temporal images are extracted frame by frame. The extracted parameters are arranged according to the time axis to construct a visual parameter temporal sequence, and the periodic change features of the visual parameter temporal sequence and the temporal arrangement order between different coding units are extracted. In the preset decoding rules that include a feature decoding mapping table, an entry matching the periodic change feature and the temporal arrangement order is searched, and the corresponding information to be transmitted is output.

[0035] In this invention, a bionic robot with visual information transmission function includes a robot body and an information transmission device mounted on the robot body. The membrane-covered bionic fish tail component of the information transmission device is disposed on the outer surface of the robot body, and the outer contour of the membrane-covered bionic fish tail component is in the shape of a bionic tail fin, pectoral fin, dorsal fin, pelvic fin or wave fin. The drive mechanism and the control unit of the information transmission device are located in the internal space of the robot body. The power output end of the drive mechanism passes through the sealed shell of the robot body and is mechanically connected to the root of the membrane bionic fish tail assembly. The control unit is communicatively connected to the main control module of the robot body and is used to receive identity features, status data, interaction instructions or synchronization signals issued by the main control module as input to the information to be transmitted in the corresponding relationship.

[0036] The motion-coded command generated by the control unit consists of reference swing parameters and information modulation parameters; The reference swing parameters are used to control the flexible fishtail base to perform periodic hydrodynamic propulsion movements; The information modulation parameters are generated by converting the information to be transmitted, and are used to superimpose on the waveform of the periodic hydrodynamic propulsion action with oscillation frequency changes, oscillation amplitude changes, or azimuth angle changes with specific timing.

[0037] More specifically, the present invention provides an information transmission device and method based on membrane-coated biomimetic fishtail motion modulation. The device includes at least:  Coated biomimetic fishtail component;  A drive mechanism for driving the controllable motion of the coated bionic fishtail component;  A control unit used to generate motion-coded instructions based on the information to be transmitted;  Optional visual receiving and decoding unit.

[0038] The biomimetic fishtail component includes a flexible fishtail substrate and an optically responsive coating layer disposed on the surface of the flexible fishtail substrate. The optically responsive coating layer can be a structural color film, pearlescent film, interference film, multilayer composite optical film, reflective film, polarization-responsive film, patterned optical film, or other coating layers that can produce differences in brightness, color, texture, or pattern depending on the viewing angle, illumination angle, fishtail posture, or fishtail deformation state.

[0039] The optical response coating is not limited to a specific material and can be a structural color film, pearlescent film, interference film, multilayer composite optical film, reflective film, polarization-responsive film, fluorescence-responsive film, angle-changing film, film with directional texture, film with coded pattern, or other materials that can produce differences in brightness, color, texture, reflection intensity, or pattern depending on the viewing angle, illumination angle, fish tail posture, or fish tail deformation state.

[0040] The optical response coating layer can be a single-layer structure or a multi-layer composite structure; it can be a continuous coverage structure or a partial coverage structure; it can cover one side of the fish tail or both sides of the fish tail; it can be set as stripes, blocks, dot matrix, partitions, QR codes, directional arrows, identification marks or other preset coding patterns.

[0041] In some embodiments, instead of using a complete film, a coating, spray coating, printing layer, patch, embedded patch, local reflective structure, microstructure texture or visual marking area with optical response function may be provided on the surface of the fish tail. As long as it can generate a recognizable dynamic visual response during the movement of the fish tail, it is an equivalent alternative of the present invention.

[0042] The control unit generates corresponding motion-coded instructions based on the information to be transmitted. These motion-coded instructions include one or more parameters such as the fishtail swaying frequency, swaying amplitude, swaying center angle, overall azimuth angle, swaying waveform, duration, pause time, number of repetitions, and motion sequence arrangement. The drive mechanism drives the coated bionic fishtail component to move according to the motion-coded instructions, causing the coating layer to generate a dynamic visual response sequence corresponding to the information to be transmitted.

[0043] The external vision receiving and decoding unit can acquire the changes in brightness, color, flicker frequency, color switching sequence, pattern changes, or spatial brightness distribution of the coated bionic fishtail component during its movement through a camera, photoelectric sensor, color sensor, polarization vision sensor, or other vision acquisition device, and identify the transmitted information according to preset decoding rules.

[0044] Coated biomimetic fishtail component The membrane-coated biomimetic fishtail component includes: Flexible fishtail substrate; An optically responsive coating layer disposed on at least one side of the surface of a flexible fishtail substrate; The installation connection area is located at the root of the flexible fishtail base; A clamping and fixing structure that connects to the mounting connection area.

[0045] The flexible fishtail substrate is used to form the main shape of a biomimetic fishtail and, under the action of a driving mechanism, produces periodic oscillations, bending deformations, or posture changes. The flexible fishtail substrate can be made of TPU, silicone, rubber, flexible resin, elastic composite materials, or other bendable materials, and can also adopt a rigid-flexible composite structure or a partitioned hardness structure.

[0046] The flexible fishtail substrate is not limited to TPU material; it can also be made of silicone, rubber, polyurethane, flexible resin, elastic composite material, fiber-reinforced flexible material, sheet elastic material, or other bendable material.

[0047] The fish tail substrate can be a single flexible structure or a rigid-flexible composite structure; it can adopt a uniform thickness design, or a partitioned thickness design, partitioned hardness design, edge reinforcement design, local thinning design, skeletal reinforcement design, or biomimetic fin structure. The fish tail shape can be fish tail-shaped, fin-shaped, wing-shaped, undulating fin-shaped, sheet-like oscillating component, or other flexible components capable of producing periodic oscillation, bending deformation, or posture changes.

[0048] Therefore, this invention is not limited to the traditional tail fin, but can also be applied to the pectoral fins, dorsal fins, pelvic fins, wave fins, flexible propulsion plates, flexible swing wings or other flexible motion components of underwater robots in biomimetic robotic fish.

[0049] The optically responsive coating layer is disposed on the main display area of ​​the flexible fishtail substrate. The main display area is the region that mainly generates visual changes and is used for information transmission during the movement of the fishtail. The optically responsive coating layer can cover one side or both sides of the flexible fishtail substrate; it can cover the entire main display area, or it can be partially covered according to stripes, blocks, dot matrix, QR code patterns, directional patterns, or coded patterns.

[0050] Preferably, the optical response coating layer has a local gap, is thinned, disconnected, or has a buffer transition area at the connection area at the base of the fish tail to reduce stress concentration during clamping and fixing, and reduce the risk of wrinkling, curling, delamination, or damage of the coating layer during repeated swinging.

[0051] The connection between the optically responsive coating layer and the fishtail substrate is not limited to adhesive bonding. It can also be achieved through hot pressing, cold pressing, vacuum bonding, overmolding, co-curing, embedding, in-mold bonding, mechanical clamping, edge pressing, stitching, spot bonding, detachable attachment, or other connection methods.

[0052] To reduce the risk of damage to the coating layer during repeated oscillations, a buffer transition zone, protective border, flexible edge sealing layer, transparent protective layer, or local reinforcement layer can be set at the edge of the coating layer. The coating layer can also be left open, disconnected, thinned, or have a low-stiffness transition structure at the connection area at the base of the fishtail to reduce stress concentration in the clamping and fixing area.

[0053] The clamping and fixing structure includes a first clamping member, a second clamping member, fasteners, and a positioning groove or limiting groove for accommodating the root connection area of ​​the fishtail. The root connection area of ​​the flexible fishtail substrate is clamped between the first and second clamping members and fixed by the fasteners. Preferably, the clamping and fixing structure may also be provided with an anti-slip layer, a buffer layer, limiting ribs, positioning holes, connecting ear plates, or drive connecting holes to improve assembly repeatability and motion stability.

[0054] The clamping and fixing structure is not limited to a clamping plate structure consisting of a first clamping member, a second clamping member, and fasteners. It can also adopt a slot-type fixing structure, a pressure plate-type fixing structure, a snap-on fixing structure, a bolt-tightening structure, an elastic clamping structure, a wedge-shaped clamping structure, a magnetic auxiliary positioning structure, a quick-release connection structure, or an integrally formed connection structure.

[0055] The clamping and fixing structure can be equipped with an anti-slip layer, a buffer layer, a limiting groove, a limiting rib, a positioning pin, a positioning hole, a guide groove, a connecting ear plate, a drive connection hole, or other positioning structures. As long as it can achieve a stable connection between the fishtail substrate and the drive mechanism and ensure that the posture changes of the coated area during movement are repeatable, it can be used as an alternative to the present invention.

[0056] Drive mechanism The drive mechanism is used to drive the coated bionic fishtail assembly to produce controllable motion according to the motion-coded instructions output by the control unit. The drive mechanism may include one or more drive degrees of freedom.

[0057] In a preferred embodiment, the driving mechanism includes a first driving mechanism and a second driving mechanism. The first driving mechanism is used to adjust the overall azimuth angle of the coated bionic fishtail assembly relative to the observation direction or the illumination direction, and the second driving mechanism is used to drive the coated bionic fishtail assembly to periodically oscillate around the oscillation axis.

[0058] The first drive mechanism can be a servo motor, stepper motor, geared motor, rotary actuator, or other drive component capable of outputting angular displacement. The output end of the first drive mechanism is connected to the rotating platform or support structure to change the overall orientation of the fishtail assembly.

[0059] The second drive mechanism is mounted on a rotating platform or support structure and can be a servo motor, a swing motor, a linkage mechanism, a flexible hinge drive mechanism, a linear drive mechanism, or other actuators capable of driving the fish tail to reciprocate. The output end of the second drive mechanism is connected to the clamping and fixing structure and is used to drive the coated bionic fish tail assembly to move according to a preset swing frequency, swing amplitude, swing center angle, and swing waveform.

[0060] Through the cooperation of the first and second drive mechanisms, a coupled modulation relationship of "overall azimuth angle adjustment - fish tail periodic oscillation - coating optical response change" can be formed, so that the same coated fish tail can produce different dynamic visual response sequences under different motion coding commands.

[0061] In another embodiment, the drive mechanism may consist of only a single-degree-of-freedom drive mechanism for the fish tail's swaying, with information encoding achieved by changing the swaying frequency, swaying amplitude, swaying center angle, duration, and pause time. Alternatively, the drive mechanism may include three or more degrees of freedom to further adjust the fish tail's pitch angle, yaw angle, roll angle, local bending shape, or spatial motion trajectory.

[0062] The drive mechanism is not limited to a servo motor, but can also be a stepper motor, DC geared motor, brushless motor, rotary actuator, linear actuator, electromagnetic actuator, piezoelectric actuator, shape memory alloy actuator, pneumatic actuator, hydraulic actuator, magnetic drive mechanism, linkage mechanism, crank rocker mechanism, flexible hinge mechanism, or other actuators that can drive the fish tail to swing, rotate, bend or change posture.

[0063] The drive mechanism can be a single-degree-of-freedom structure, which encodes information only through the frequency, amplitude, center angle, duration, and pause time of the fishtail swing; it can also be a two-degree-of-freedom structure, which encodes information through the overall azimuth adjustment and the fishtail swing; or it can be a three-degree-of-freedom or multi-degree-of-freedom structure, which encodes more complex information through various motion parameters such as yaw, pitch, roll, local bending, and spatial trajectory changes.

[0064] In some implementations, the overall azimuth adjustment mechanism can be omitted, and the equivalent observation angle adjustment can be achieved by the robot body's steering, posture adjustment, or changes in its swimming trajectory.

[0065] Control Unit The control unit is used to receive or generate information to be transmitted and convert the information into corresponding motion-coded instructions. The control unit may include one or more of the following: microcontroller, single-chip microcomputer, embedded control board, host computer, wireless control module, storage module, and drive control output terminal.

[0066] The information to be transmitted may include identification number, robot status, task status, direction prompts, simple instructions, warning information, synchronization signals, formation markings, or other preset information.

[0067] The motion coding instruction may include at least one of the following parameters:  Oscillation frequency;  Swing amplitude;  Oscillation center angle; Overall azimuth;  Oscillating waveform;  Duration of a single coding unit;  The pause time between adjacent coding units; The number of repetitions in the encoded sequence;  The order of combination of different motion parameters.

[0068] For example, different swing frequencies can be associated with different information symbols; different swing amplitudes can also be associated with different information symbols; and swing frequency, swing amplitude, and overall azimuth angle can be combined to form a multi-dimensional code. Through a preset encoding table, the control unit can convert the information to be transmitted into a set of continuous or discrete motion sequences, so that the membrane-covered bionic fish tail generates a corresponding visual response sequence during the movement.

[0069] Information encoding method The information encoding method of this invention can employ single-parameter encoding or multi-parameter combination encoding.

[0070] In single-parameter encoding, information can be encoded by changing the frequency of the fishtail's wagging. For example, the first wagging frequency represents the first information symbol, the second wagging frequency represents the second information symbol, and the third wagging frequency represents the third information symbol. The visual receiver identifies the corresponding information symbol by recognizing the flickering frequency of changes in the brightness or color of the coated fishtail.

[0071] In another single-parameter encoding method, information encoding can be achieved by changing the swing amplitude. For example, a small swing amplitude represents the first information symbol, a large swing amplitude represents the second information symbol, and stopping the swing amplitude represents the interval symbol or calibration symbol.

[0072] In multi-parameter combination encoding, information can be encoded simultaneously using oscillation frequency, oscillation amplitude, overall azimuth angle, duration, and pause time. For example, a certain frequency combined with a certain azimuth angle corresponds to identity information, while another frequency combined with another azimuth angle corresponds to task status information. By combining multiple parameters, information capacity and anti-interference capability can be improved.

[0073] In a further embodiment, optical response structures with different regions, directions, or patterns can be formed on the coating layer, allowing the fish tail to exhibit different spatial pattern changes under different swaying postures. The visual receiver can decode specific information by recognizing changes in pattern brightness, color sequence, or spatial distribution.

[0074] The information encoding method of the present invention is not limited to encoding by swing frequency, but can also be implemented by swing amplitude, swing center angle, overall azimuth angle, swing waveform, swing duration, stop time, number of repetitions, motion direction, motion phase, motion trajectory or a combination of multiple parameters.

[0075] For example, different swing frequencies can be used to represent different information symbols; different swing amplitudes can be used to represent different states; different azimuth angles can be used to represent different identities; different flashing rhythms can be used to represent different instructions; a combination of "short swing - long swing" can be used to represent binary information; a combination of frequency, amplitude and duration can be used to represent multi-level information; or a preset motion sequence can be used to represent complete identity numbers, status information, task information or synchronization signals.

[0076] The encoding rules can be binary encoding, multi-base encoding, frequency keying encoding, amplitude keying encoding, phase keying encoding, time-division encoding, pulse width encoding, sequence encoding, lookup table encoding, custom symbol code, redundancy check encoding, or other information encoding methods suitable for visual recognition.

[0077] Visual receiving and decoding unit The visual receiving and decoding unit is used to acquire the dynamic visual response during the movement of the bionic fish tail covered with a membrane, and to obtain the transmitted information according to a preset decoding rule. The visual receiving and decoding unit can be set in an external observation device, another underwater robot, a mother platform, a shore-based observation system, an experimental camera system, or an operator's visual observation system.

[0078] The visual receiving and decoding unit may include an image acquisition module, a brightness extraction module, a color recognition module, a frequency analysis module, a timing recognition module, and a decoding module.

[0079] The image acquisition module is used to acquire motion images or local visual signals of the bionic fish tail covered with film; the brightness extraction module is used to extract the average brightness, maximum brightness, brightness variation amplitude, or brightness variation frequency of the covered area; the color recognition module is used to extract the hue, saturation, color change sequence, or color distribution of the covered area; the frequency analysis module is used to identify periodic changes in the visual response; the timing recognition module is used to identify the sequence between different coding units; and the decoding module converts the recognition results into corresponding information content according to a preset encoding table.

[0080] The present invention also provides an information transmission method based on the modulation of biomimetic fish tail motion with a membrane coating, the method comprising the following steps: Establish coding rules.

[0081] A pre-established correspondence between the information to be transmitted and the motion-coded instructions is established. The motion-coded instructions include one or more of the following: swing frequency, swing amplitude, swing center angle, overall azimuth angle, swing waveform, duration, and pause time.

[0082] Obtain the information to be transmitted.

[0083] The control unit acquires the information that needs to be transmitted, which may be an identification number, status information, task information, direction prompts, synchronization signals, or preset instructions.

[0084] Generate motion coding instructions.

[0085] The control unit converts the information to be transmitted into corresponding motion-coded instructions according to the encoding rules.

[0086] Drive the biomimetic fish tail motion with a membrane coating.

[0087] The driving mechanism drives the coated bionic fishtail component to generate corresponding movements according to the motion coding instructions, so that the optical response coating layer produces corresponding brightness changes, color changes, flickering changes or pattern changes during the movement.

[0088] Capture dynamic visual responses.

[0089] The visual receiver acquires the dynamic visual response of the coated bionic fishtail component during its movement, obtaining brightness sequences, color sequences, pattern sequences, or frequency characteristics.

[0090] Decode the information.

[0091] The visual receiver converts the acquired dynamic visual response into corresponding information content according to the preset decoding rules.

[0092] Optionally, the recognition results can be output or fed back.

[0093] The visual receiver can output the decoding results to display devices, control systems, robot collaboration systems or task management systems, and can also trigger subsequent control actions based on the recognition results.

[0094] This invention can be applied to the following scenarios: Close-range identification and status alerts between biomimetic robotic fish; Visual recognition and status assessment of the mother platform to the daughter platform in a mother-daughter bionic submersible; Non-actively luminous visual markers in underwater low-disturbance observation scenarios; Transmission of simple commands or synchronization signals in underwater robot swarm collaboration; Visualized information transmission demonstrations in water tank experiments, science popularization displays, and teaching experiments; Underwater equipment requiring low power consumption, low complexity, and low-disturbance visual cues.

[0095] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. 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 of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. An information transmission device based on membrane-coated biomimetic fishtail motion modulation, characterized in that, include: A coated biomimetic fish tail component, the coated biomimetic fish tail component comprising a flexible fish tail substrate and an optically responsive coating layer disposed on at least one side of the surface of the flexible fish tail substrate; The control unit internally stores the correspondence between information to be transmitted and motion coding instructions. The control unit is used to acquire the information to be transmitted and generate the corresponding motion coding instructions according to the correspondence. A drive mechanism, the control end of which is connected to the control unit, and the power output end of which is connected to the flexible fishtail substrate; the drive mechanism is used to drive the membrane-coated bionic fishtail component to perform a preset spatial movement according to the motion coding instructions; The optically responsive coating layer performs the spatial motion synchronously with the flexible fishtail substrate, changing the light-receiving angle and spatial posture of the surface of the optically responsive coating layer relative to the external illumination direction and the observation direction, and outputting a dynamic visual response sequence modulated by the motion coding command.

2. The information transmission device based on membrane-coated biomimetic fishtail motion modulation according to claim 1, characterized in that, The motion coding instruction includes at least one of the following parameters: swing frequency, swing amplitude, swing center angle, overall azimuth angle, swing waveform, duration of a single coding unit, pause time between adjacent coding units, and number of repetitions of the coding sequence. The optically responsive coating is at least one of the following: structural color film, pearlescent film, interference film, multilayer composite optical film, reflective film, and polarization-responsive film. The dynamic visual response sequence includes at least one of the following: brightness change sequence, color change sequence, flicker frequency change sequence, color switching sequence, pattern change sequence, and spatial brightness distribution change sequence.

3. The information transmission device based on membrane-coated biomimetic fishtail motion modulation according to claim 1, characterized in that, The membrane-coated bionic fishtail assembly also includes an installation connection area located at the root of the flexible fishtail substrate, and a clamping and fixing structure fitted to the installation connection area. The clamping and fixing structure includes a first clamping member, a second clamping member, and a fastener. The mounting connection area of ​​the flexible fishtail substrate is disposed between the first clamping member and the second clamping member, and is fastened together by the fastener. The optically responsive coating layer is disposed on the main display area of ​​the flexible fishtail substrate other than the mounting connection area, or the optically responsive coating layer is in a void, disconnected or thinned structure in the mounting connection area between the first clamping member and the second clamping member.

4. The information transmission device based on membrane-coated biomimetic fishtail motion modulation according to claim 1, characterized in that, The driving mechanism includes a first driving mechanism, a support structure, and a second driving mechanism; The power output end of the first driving mechanism is connected to the support structure and is used to drive the support structure to rotate around the first axis; The second drive mechanism is disposed on the support structure, and the power output end of the second drive mechanism is connected to the root of the membrane bionic fish tail component, for driving the membrane bionic fish tail component to reciprocate around the second axis.

5. The information transmission device based on membrane-coated biomimetic fishtail motion modulation according to claim 1, characterized in that, The device also includes a visual receiving and decoding unit; The visual receiving and decoding unit includes an image acquisition module and a decoding module; The image acquisition module's acquisition end faces the coated bionic fishtail component, and is used to acquire continuous temporal images of the optical response coating layer during the spatial motion process; The decoding module stores a preset decoding rule table. The decoding module is used to extract the visual feature sequence of the optical response coating layer in the continuous time-series images, and perform mapping and comparison in the preset decoding rule table to convert it into the corresponding information to be transmitted.

6. An information transmission method based on membrane-coated bionic fishtail motion modulation, applied to the information transmission device based on membrane-coated bionic fishtail motion modulation as described in any one of claims 1 to 5, characterized in that, Includes the following steps: Step S1: Configure the correspondence between the information to be transmitted and the motion coding instructions in the control unit; Step S2: The control unit acquires the input information to be transmitted and generates the corresponding motion coding instruction according to the correspondence. Step S3: The drive mechanism receives the motion coding instruction sent by the control unit, and drives the coated bionic fish tail assembly, which includes a flexible fish tail substrate and an optically responsive coating layer, to perform corresponding spatial movements according to the motion coding instruction. Step S4: The optical response coating layer moves synchronously with the flexible fishtail substrate in space, generating changes in relative spatial posture and light-receiving angle, and outputting a dynamic visual response sequence corresponding to the information to be transmitted. Step S5: The visual receiving and decoding unit acquires the dynamic visual response sequence and converts the extracted sequence features into the information to be transmitted according to the preset decoding rules.

7. The information transmission method based on membrane-coated biomimetic fishtail motion modulation according to claim 6, characterized in that, In step S2, the correspondence includes at least one of single-parameter encoding rules and multi-parameter combination encoding rules; The single-parameter encoding rule includes mapping different contents of the information to be transmitted to a single swing frequency or a single swing amplitude of different values. The multi-parameter combination encoding rule includes mapping the information to be transmitted with different contents into a specific time sequence composed of two or more parameters among swing frequency, swing amplitude, overall azimuth angle and duration.

8. The information transmission method based on membrane-coated biomimetic fishtail motion modulation according to claim 6, characterized in that, Step S5 includes: Acquire continuous time-series images of the membrane-coated bionic fishtail component during its movement; The average brightness, maximum brightness, hue value, saturation value, or spatial distribution parameters of the optical response coating layer region in the continuous temporal images are extracted frame by frame. The extracted parameters are arranged according to the time axis to construct a visual parameter temporal sequence, and the periodic change features of the visual parameter temporal sequence and the temporal arrangement order between different coding units are extracted. In the preset decoding rules that include a feature decoding mapping table, an entry matching the periodic change feature and the temporal arrangement order is searched, and the corresponding information to be transmitted is output.

9. A biomimetic robot with visual information transmission function, characterized in that, Includes a robot body, and an information transmission device based on the motion modulation of a membrane-coated bionic fish tail, as described in any one of claims 1 to 5, mounted on the robot body; The membrane-covered bionic fish tail component of the information transmission device is disposed on the outer surface of the robot body, and the outer contour of the membrane-covered bionic fish tail component is in the shape of a bionic tail fin, pectoral fin, dorsal fin, pelvic fin or wave fin. The drive mechanism and the control unit of the information transmission device are located in the internal space of the robot body. The power output end of the drive mechanism passes through the sealed shell of the robot body and is mechanically connected to the root of the membrane bionic fish tail assembly. The control unit is communicatively connected to the main control module of the robot body and is used to receive identity features, status data, interaction instructions or synchronization signals issued by the main control module as input to the information to be transmitted in the corresponding relationship.

10. The bionic robot with visual information transmission function according to claim 9, characterized in that, The motion-coded command generated by the control unit consists of reference swing parameters and information modulation parameters; The reference swing parameters are used to control the flexible fishtail base to perform periodic hydrodynamic propulsion movements; The information modulation parameters are generated by converting the information to be transmitted, and are used to superimpose on the waveform of the periodic hydrodynamic propulsion action with oscillation frequency changes, oscillation amplitude changes, or azimuth angle changes with specific timing.

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