An underwater vehicle based on electrochemical gas regulation

Abstract

The application discloses an underwater submerged vehicle based on electrochemical gas regulation, which comprises a mother ship, a silent buoyancy adjusting unit and a hydrofoil power unit; the silent buoyancy adjusting unit comprises a reaction cabin, electrolytic electrodes, an ionic liquid storage cabin, a gas permeation membrane and a flexible airbag; the reaction cabin is fixed on the mother ship and communicates with the flexible airbag; the ionic liquid storage cabin is installed in the reaction cabin and is filled with ionic liquid with CO2 releasing and absorbing capacity; the ionic liquid storage cabin is provided with an opening and is covered with the gas permeation membrane; the electrolytic electrodes are inserted into the ionic liquid and are used for realizing electrochemical reversible absorption and release of CO2; and the hydrofoil power unit comprises a gliding hydrofoil, a water surface lifting hydrofoil and a propeller. The application adopts electric control ionic liquid chemical reaction to replace mechanical movement, the releasing and absorbing process of CO2 is only carried out at a molecular level and there is no moving part, so that the generation of mechanical noise is fundamentally eliminated, the concealment of the device is greatly improved and the device is difficult to be found when working underwater.

Description

Technical Field

[0001] This invention belongs to the field of marine engineering technology and underwater vehicle technology, and more specifically, it relates to an underwater vehicle based on electrochemical gas regulation. Background Technology

[0002] Covert marine environmental observation is of paramount importance in many key areas, including maritime national defense and security. It provides accurate and reliable data support for marine resource development and protection, marine scientific research, and is an indispensable technological means to safeguard the marine ecological environment and promote marine economic development. Through covert observation, changes in the marine environment can be monitored in real time, potential threats can be detected, and the status of marine resources can be assessed, thereby providing scientific evidence to ensure the smooth operation of marine activities and the sustainable use of marine resources. Currently, the main technologies in this field include underwater gliders (AUGs), autonomous underwater vehicles (AUVs), buoys, and traditional manned survey vessels. However, existing technologies have significant limitations in achieving long-term, silent, energy-self-sufficient covert observation and high-speed arrival at target locations, specifically in the following aspects:

[0003] ① Noise and Energy Consumption Issues of Buoyancy-Driven Systems: Traditional underwater gliders are an important tool for marine environmental observation. Their working principle mainly utilizes hydraulic or electric pumps to change the volume of an external oil bladder, thereby adjusting net buoyancy to achieve gliding motion. While this technology is relatively mature, it has some insurmountable drawbacks in practical applications. First, mechanical pumps generate significant vibration and noise spectrum characteristics during operation. These characteristic signals are easily captured by underwater acoustic detection systems, compromising the stealth of underwater gliders during observation missions. This makes them vulnerable to detection by hostile forces or in sensitive areas, significantly reducing the effectiveness and security of observations. Second, the energy efficiency of mechanical drive mechanisms is relatively low. Continuous pumping to maintain gliding motion consumes a large amount of electrical energy. This not only limits the endurance of underwater gliders but also increases their dependence on energy replenishment, making it difficult for them to fully play their role in long-term, continuous, covert marine environmental observation missions and failing to meet the needs of long-term, stable, and covert observation in fields such as marine national defense and security.

[0004] ② The Challenge of High Speed ​​and Long Endurance: Traditional unmanned underwater vehicles (UUVs) and unmanned surface vessels (USVs) play a vital role in marine environmental observation, but a difficult trade-off exists between high speed and long endurance. From a structural design perspective, most traditional UUVs adopt conventional hull or submersible shapes, resulting in a large contact area with the water. During navigation, they experience significant wave-making and frictional drag, lacking effective drag reduction measures. This means that UUVs require substantial energy to overcome these drags at high speeds, and upon reaching the target location, insufficient energy reserves often prevent prolonged operations and subsequent return voyages. Therefore, traditional UUVs struggle to simultaneously achieve high-speed target arrival and sufficient endurance to complete complex marine environmental observation tasks, significantly limiting their application in fields such as maritime defense and security where timeliness and continuity are crucial.

[0005] ③ Limitations in Measurement Dimensions and Depth: Traditional underwater gliders or autonomous underwater vehicles (AUVs) typically carry fixed sensors for marine environmental observation, and their detection range is primarily limited by the vehicle's trajectory. This single observation method lacks flexibility when facing complex terrain, underwater caves, or specific key targets. For example, when observing complex terrains such as seamounts and trenches, the fixed trajectory makes it difficult to comprehensively and deeply explore the fine structures of these terrains; similarly, it is difficult to enter the interior of underwater caves for detailed investigation. Although some studies have proposed the concept of collaborative observation between the mother and daughter vessels, attempting to expand the observation range through the activities of the daughter vessels, the activity range of the daughter vessels is still limited by the limited activity range of the mother vessel. This makes multi-dimensional, deep-depth collaborative covert observation difficult to truly achieve, failing to meet the requirements of comprehensive, multi-layered, and high-precision marine environmental observation in fields such as marine defense and security, and limiting the exploration of unknown marine areas and the comprehensive monitoring capabilities of potential threats. Summary of the Invention

[0006] This invention aims to at least solve one of the technical problems existing in the prior art. To this end, this invention provides an underwater vehicle based on electrochemical gas control, which aims to significantly improve the problems of poor stealth, short endurance, poor high speed, and limited observation dimensions in the prior art.

[0007] To achieve the above objectives, the present invention adopts the following technical solution: an underwater vehicle based on electrochemical gas regulation, comprising a mother boat, a silent buoyancy adjustment unit, a hydrofoil power unit, and a control and communication unit;

[0008] Multiple silent buoyancy adjustment units are distributed around the bottom outer perimeter of the mothership. Each silent buoyancy adjustment unit includes a reaction chamber, an electrolytic electrode, an ionic liquid storage chamber, a gas permeation membrane, and a flexible airbag. The reaction chamber is fixed to the mothership and connected to the flexible airbag through multiple air vents. The ionic liquid storage chamber is installed inside the reaction chamber and contains an ionic liquid with CO2 release and absorption capabilities. The ionic liquid storage chamber has openings and is covered by the gas permeation membrane. The electrolytic electrode... The positive and negative electrodes extend into the ionic liquid. The control and communication unit controls the direction and intensity of the electric field applied to the positive and negative electrodes of the electrolysis electrode to achieve electrochemical reversible absorption and release of CO2: when a reducing electric field is applied to the electrolysis electrode, CO2 in the ionic liquid is released into the flexible gasbag, increasing the volume of the flexible gasbag and thus increasing buoyancy to make the mothership float; when an oxidizing electric field is applied to the electrolysis electrode, CO2 in the flexible gasbag is absorbed by the ionic liquid, decreasing the volume of the flexible gasbag and thus reducing buoyancy to make the mothership submerge.

[0009] The hydrofoil power unit includes a gliding hydrofoil, a water-lifting hydrofoil, and a propulsion unit. The two gliding hydrofoils are symmetrically arranged on both sides of the stern of the mothership and can be folded and retracted relative to the mothership. The two water-lifting hydrofoils are respectively arranged in the middle and at the bottom of the stern of the mothership. The propulsion unit is mounted on the water-lifting hydrofoil located at the bottom of the stern of the mothership.

[0010] As a preferred option, this underwater vehicle has two modes: high-speed surface navigation and silent underwater navigation.

[0011] In the high-speed water surface navigation mode, the gliding hydrofoil is in a folded state. The control and communication unit generates lift by adjusting the angle of attack of the water surface lifting hydrofoil, so that part of the mothership leaves the water surface, which significantly reduces frictional drag and wave-making drag. The propulsion unit enables the mothership to travel at high speed and over long distances.

[0012] Upon reaching the mission area, the underwater vehicle switches to underwater gliding mode. At this time, the control and communication unit shuts down the thrusters and controls the deployment of the gliding hydrofoils. Simultaneously, it controls the electrolytic electrodes to periodically apply reducing and oxidizing electric fields, enabling the mothership to advance by relying on the horizontal component of lift generated by the gliding hydrofoils during the periodic "dive-surface" process, thus achieving continuous and silent underwater gliding.

[0013] Preferably, the ionic liquid is a 1-butyl-3-methylimidazolium tetrafluoroborate solution pre-dissolved with CO2.

[0014] Preferably, the electrochemically reversible adsorption and desorption process of CO2 achieved by the 1-butyl-3-methylimidazolium tetrafluoroborate solution is as follows:

[0015] When the electrolytic electrode applies a reducing electric field to the ionic liquid, the cations in the ionic liquid gain electrons at the cathode and are reduced to neutral molecules, which greatly reduces their ability to bind CO2. This causes the pre-dissolved CO2 gas to be rapidly released. The released CO2 gas is discharged into the flexible gasbag through the gas permeation membrane, which reduces the relative density of the mothership to generate positive buoyancy, thereby propelling the mothership to float.

[0016] Conversely, when the electrolytic electrode applies an oxidation electric field to the ionic liquid, the neutral molecules in the ionic liquid lose electrons at the anode and are oxidized back to their original ionic state. At this time, their ability to bind CO2 is enhanced again, and they begin to extract CO2 gas from the flexible gasbag. This absorption process reduces the relative density of the mothership to form negative buoyancy, thereby prompting the mothership to dive.

[0017] Preferably, the control and communication unit is equipped with a PID controller, which is electrically connected to the electrolysis electrode. By precisely controlling the voltage magnitude and duration of the electric field applied to the electrolysis electrode, the release and absorption of CO2 can be accurately regulated, thereby achieving millinewton-level fine-tuning of net buoyancy.

[0018] Preferably, the PID controller is pre-loaded with the following ideal gas state mathematical model and ionic liquid absorption and CO2 release mathematical model:

[0019] ;

[0020] ;

[0021] In the formula, This represents the volume change of CO2 gas. n CO2 This refers to the molar amount of CO2 released. R It is the ideal gas constant; T It is the temperature of the gas; p It is the pressure of the gas; I The current released by the electrolytic electrodes; t The duration for which an electric field is applied to the electrolytic electrodes; η For current efficiency; z The number of electrons in the reaction; F It is Faraday's constant;

[0022] The volume of CO2 gas required to produce a specific change in buoyancy can be accurately calculated using the mathematical model described above. This allows for the reverse calculation of the magnitude and duration of the electric field applied to the electrolytic electrode, thus enabling precise fine-tuning of the net buoyancy.

[0023] Preferably, the system also includes an ROV, and an ROV deployment and retrieval compartment is provided at the stern of the mother vessel. The ROV deployment and retrieval compartment is equipped with a deployment and retrieval mechanism and a wireless charging coil assembly. The ROV is placed in the ROV deployment and retrieval compartment and connected to the mother vessel via an optical fiber composite cable and the deployment and retrieval mechanism.

[0024] Preferably, the dynamics of the high-speed surface navigation mode can be described as a typical lift-supported motion mechanism, and its dynamic model can be expressed as:

[0025] ;

[0026] In the formula, L For the lift of the mothership; ρ The density of the water body; U The speed of the mothership; S The airfoil planar area for water-lifting hydrofoils; C L This is the lift coefficient.

[0027] As a preferred embodiment, the dynamic model of the underwater gliding and submersible navigation mode can be expressed as:

[0028] ;

[0029] In the formula, F net The net buoyancy force on the mother ship; m For the mass of the mothership; g It is the acceleration due to gravity; ρ The density of the water body; V To create space for the mothership.

[0030] Preferably, the control and communication unit is composed of an embedded processor. The control unit, combined with an inertial measurement unit, depth sensor, temperature sensor and current meter, realizes autonomous state perception and decision-making. The control algorithm adopts a hierarchical architecture, with the upper layer being the task planning layer and the lower layer being the attitude and execution layer. The communication unit uses satellite link for remote communication on the water surface and transmits through acoustic modulation underwater.

[0031] The present invention has the following advantages due to the adoption of the above technical solutions:

[0032] 1. Significantly reduces noise and improves concealment

[0033] Traditional underwater gliders are easily detected acoustically due to the broadband mechanical vibrations and fluid noise generated by the operation of mechanical components such as hydraulic pumps, motors, and valves. This invention, however, uses an electrically controlled ionic liquid chemical reaction to replace mechanical movement. The release and absorption of CO2 occurs only at the molecular level, with no moving parts, fundamentally eliminating mechanical noise. The only possible sound comes from the faint bubble sound generated during electrolysis, whose sound pressure level and spectral characteristics are far lower than those of mechanical pumps and closer to ambient noise, making it difficult to detect and identify. This significantly reduces noise, greatly enhances the device's stealth, and makes it harder to be detected underwater, increasing its application value in military reconnaissance, marine covert detection, and other fields.

[0034] 2. Significantly extends battery life and reduces energy consumption.

[0035] During the surface navigation phase, this invention utilizes hydrofoil lift to suspend the mother vessel, effectively reducing the contact area between the mother vessel and the water surface, thereby significantly reducing navigation resistance. During the underwater submersible phase, hydrofoils, in conjunction with a silent buoyancy adjustment unit, provide gliding propulsion, eliminating the need for underwater propulsion. In both phases, the hydrofoil effect significantly reduces the average propulsion power, thereby greatly extending endurance, reducing energy consumption, enabling the submersible to perform missions for longer periods, expanding its operational range, and improving its applicability and economy in long-term ocean monitoring and long-range exploration missions.

[0036] 3. Construct a master-slave collaborative three-dimensional observation system to significantly improve the efficiency and quality of marine environmental data acquisition.

[0037] This invention constructs a multi-modal collaborative three-dimensional observation system consisting of a "mother vessel (gliding / surface) – remotely operated vehicle (ROV)". The mother vessel ensures the device's remote, long-term operation, energy replenishment, and communication, providing a stable operational foundation and continuous energy support for the entire system. The ROV, acting as a slave platform, can conduct close-range, high-resolution surveys and sampling in seabed and rocky crevices, enabling detailed exploration of complex terrain and specific target areas. This collaborative approach significantly improves the effective sample rate and information entropy increment of marine environmental data, achieving comprehensive, multi-dimensional, and high-precision observation of the marine environment. It provides richer and more accurate data support for marine scientific research and resource exploration, improving data acquisition efficiency and quality, and enhancing our understanding and knowledge of the marine environment. Attached Figure Description

[0038] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Throughout the drawings, the same reference numerals denote the same parts. In the drawings:

[0039] Figure 1 This is a schematic diagram of the structure of a multi-submarine vehicle provided in an embodiment of the present invention;

[0040] Figure 2 This is a state diagram of the underwater vehicle in high-speed surface navigation mode provided in this embodiment of the invention;

[0041] Figure 3 This is a state diagram of the underwater vehicle in underwater gliding and submersible mode provided in this embodiment of the invention;

[0042] Figure 4 This is a schematic diagram of the structure of a silent buoyancy adjustment unit provided in an embodiment of the present invention.

[0043] The labels for the attached figures are as follows:

[0044] 1. Mothership; 2. Silent buoyancy adjustment unit; 3. Hydrofoil power unit; 4. Remotely operated unmanned underwater vehicle;

[0045] 1-1 ROV deployment and recovery chamber; 2-1 reaction chamber; 2-2 electrolytic electrode; 2-3 ionic liquid storage chamber; 2-4 gas permeation membrane; 2-5 flexible airbag; 3-1 glider hydrofoil; 3-2 water surface lifting hydrofoil; 3-3 propulsion unit. Detailed Implementation

[0046] To make the objectives, technical solutions, and advantages of the present invention clearer, specific embodiments of the present invention will be further described below with reference to the accompanying drawings. Although exemplary embodiments of the present invention are shown in the drawings, it should be understood that the present invention can be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided to enable a more thorough understanding of the present invention and to fully convey the scope of the present invention to those skilled in the art.

[0047] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0048] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0049] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0050] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0051] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0052] The underwater vehicle based on electrochemical gas regulation provided in the embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0053] Please see Figure 1 The underwater vehicle based on electrochemical gas regulation provided in this embodiment includes a mother boat 1, a silent buoyancy adjustment unit 2, a hydrofoil power unit 3, and a control and communication unit (not shown in the figure).

[0054] Four silent buoyancy adjustment units 2 are distributed around the bottom of the mothership 1. Each silent buoyancy adjustment unit 2 includes a reaction chamber 2-1, an electrolytic electrode 2-2, an ionic liquid storage chamber 2-3, a gas permeation membrane 2-4 (polydimethylsiloxane PDMS membrane), and a flexible airbag 2-5. The reaction chamber 2-1 is fixed to the mothership 1 and is connected to the flexible airbag 2-5 through multiple air holes. The ionic liquid storage chamber 2-3 is installed inside the reaction chamber 2-1 and contains an ionic liquid with CO2 release and absorption capabilities. The ionic liquid storage chamber 2-3 has openings and is covered by the gas permeation membrane 2-4. The positive and negative electrodes of the electrolysis electrode 2-2 extend into the ionic liquid. The control and communication unit controls the direction and intensity of the electric field applied to the positive and negative electrodes of the electrolysis electrode 2-2 to achieve electrochemical reversible absorption and release of CO2. Specifically, when a reducing electric field is applied to the electrolysis electrode 2-2, CO2 in the ionic liquid is released into the flexible gasbag 2-5, increasing the volume of the flexible gasbag 2-5 and thus increasing buoyancy to make the mothership 1 float. When an oxidizing electric field is applied to the electrolysis electrode 2-2, CO2 in the flexible gasbag 2-5 is absorbed by the ionic liquid, decreasing the volume of the flexible gasbag 2-5 and thus reducing buoyancy to make the mothership 1 submerge.

[0055] The hydrofoil propulsion unit 3 includes a gliding hydrofoil 3-1, a water-lifting hydrofoil 3-2, and a propeller 3-3. The two gliding hydrofoils 3-1 are symmetrically arranged on both sides of the stern of the mothership 1 and can be folded and stowed relative to the mothership 1. The two water-lifting hydrofoils 3-2 are respectively arranged in the middle and at the bottom of the stern of the mothership 1. The propeller 3-3 is mounted on the water-lifting hydrofoils 3-2 located at the bottom of the stern of the mothership 1. In high-speed surface navigation mode, the gliding hydrofoils 3-1 are in a folded state. The control and communication unit generates lift by adjusting the angle of attack of the water-lifting hydrofoils 3-2, allowing the mothership 1 to partially detach from the water surface, significantly reducing frictional drag and wave-making drag. The propeller 3-3 enables high-speed, long-distance navigation of the mothership 1. During this process, the vertical component of the lift from the water-lifting hydrofoils 3-2 bears the weight of the mothership 1, while the horizontal component, together with the propulsion, overcomes drag, achieving stable forward movement. Upon reaching the mission area, the underwater vehicle switches to underwater gliding mode. At this time, the control and communication unit shuts down the thrusters 3-3 and deploys the hydrogliding glider 3-1. Simultaneously, it controls the electrolytic electrodes 2-2 to periodically apply reducing and oxidizing electric fields. This allows the mother vessel 1 to propel itself forward using the horizontal component of lift generated by the hydrogliding glider 3-1 during periodic "dive-surface" maneuvers, achieving continuous and silent underwater gliding. Compared to traditional propeller propulsion, underwater gliding offers significant advantages, greatly enhancing the survivability and mission sustainability of the observation equipment in covert reconnaissance missions. Furthermore, because it does not rely on high-speed rotating components, underwater gliding also boasts higher reliability and lower mechanical wear, making it suitable for long-term unattended ocean monitoring missions.

[0056] In the above embodiments, preferably, the ionic liquid with CO2 release and absorption capabilities is a 1-butyl-3-methylimidazolium tetrafluoroborate solution ([bmim][BF4]) pre-dissolved with CO2. When the electrolytic electrode 2-2 applies a reducing electric field to the ionic liquid, the cations in the ionic liquid (such as [bmim]+) gain electrons at the cathode and are reduced to neutral molecules, resulting in a significant reduction in their ability to bind CO2. This causes the pre-dissolved CO2 gas to be rapidly released. The released CO2 gas is discharged into the flexible gasbag 2-5 through the gas permeation membrane 2-4, reducing the relative density of the mothership 1 to generate positive buoyancy, thereby propelling the mothership 1 to float. Conversely, when the electrolytic electrode 2-2 applies an oxidizing electric field to the ionic liquid, the neutral molecules in the ionic liquid lose electrons at the anode and are oxidized back to their original ionic state. At this time, their ability to bind CO2 is enhanced again, and they begin to extract CO2 gas from the flexible gasbag 2-5. This absorption process reduces the relative density of the mothership 1 to form negative buoyancy, thereby causing the mothership 1 to submerge.

[0057] In the above embodiments, preferably, the control and communication unit is equipped with a PID controller, which is electrically connected to the electrolysis electrode 2-2. By precisely controlling the magnitude and duration of the electric field applied to the electrolysis electrode 2-2, the release and absorption of CO2 can be accurately regulated, thereby achieving millinewton-level fine-tuning of net buoyancy. Specifically, the PID controller is pre-loaded with the following mathematical models: ideal gas state mathematical model and mathematical model for CO2 absorption and release by ionic liquid:

[0058] ;

[0059] ;

[0060] In the formula, This represents the volume change of CO2 gas. n CO2 This refers to the molar amount of CO2 released. R It is the ideal gas constant; T It is the temperature of the gas; p It is the pressure of the gas; I The current released by the electrolytic electrodes; t The duration for which an electric field is applied to the electrolytic electrodes; η For current efficiency; z The number of electrons in the reaction (for the [bmim]+ reduction reaction, take...) z =1); F is the Faraday constant, with a value of 96485 C / mol.

[0061] The mathematical model described above can be used to accurately calculate the volume ΔV of CO2 gas that needs to be discharged to generate a specific change in buoyancy. This allows us to deduce the magnitude of the current and the duration of the electric field applied to the electrolytic electrode 2-2, thus enabling precise fine-tuning of the net buoyancy.

[0062] In the above embodiments, preferably, a remotely controlled ROV4 (underwater robot) is also included. An ROV deployment and retrieval compartment 1-1 is located at the stern of the mother vessel 1. The ROV deployment and retrieval compartment 1-1 is equipped with a deployment and retrieval mechanism and a wireless charging coil assembly (not shown in the figure). The ROV4 is placed inside the ROV deployment and retrieval compartment 1-1 and connected to the mother vessel 1 via a fiber optic composite cable and the deployment and retrieval mechanism. This setup forms a master-slave collaborative operation architecture of "mother vessel + ROV". In collaborative operation mode, the mother vessel acts as a "mobile base" and "communication relay station," typically hovering underwater or gliding at low speed. The ROV4 can be autonomously released from the ROV deployment and retrieval compartment 1-1 by the deployment and retrieval mechanism, relying on its own power to enter complex and confined spaces, sensitive areas, or deeper waters that are difficult for the mother vessel 1 to reach, performing detailed detection and / or sampling tasks. The acquired detection data is transmitted back to the mother vessel 1 in real time via the fiber optic composite cable, and then the mother vessel uploads the data to a ground receiving station via a satellite link or a pre-installed antenna. After completing its mission, the ROV4 automatically returns, precisely docking with the wireless charging coil assembly via a positioning beacon and automatically charging itself in preparation for the next mission. This master-slave collaborative structure enables long-term unattended operation and significantly improves the spatial resolution and information coverage of observations.

[0063] In the above embodiments, preferably, the dynamics of the underwater vehicle's high-speed surface navigation mode can be described as a typical lift-supported motion mechanism, and its dynamic model can be expressed as:

[0064] ;

[0065] In the formula, L For the lift of the mothership; ρ The density of the water body; U The speed of the mothership; S The airfoil planar area for water-lifting hydrofoils; C L This is the lift coefficient.

[0066] The dynamic model of the underwater gliding and navigation mode of an underwater vehicle can be expressed as:

[0067] ;

[0068] In the formula, F net The net buoyancy force on the mother ship; m For the mass of the mothership; g It is the acceleration due to gravity; ρThe density of the water body; V To create space for the mothership. This is achieved by controlling the amount of CO2 gas released or absorbed to regulate... F net The value indicates whether the object is rising or sinking.

[0069] In the above embodiments, preferably, the control and communication unit is composed of an embedded processor. The control unit, combined with an inertial measurement unit, depth sensor, temperature sensor, and current meter, achieves autonomous state perception and decision-making. The control algorithm adopts a layered architecture, with the upper layer being the task planning layer and the lower layer being the attitude and execution layer. The communication unit uses a satellite link for remote communication on the water surface and transmits via acoustic modulation underwater.

[0070] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and not to limit them. Although this application 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 therein. 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 this application, and they should all be covered within the scope of the claims and specification of this application. In particular, as long as there is no structural conflict, the various technical features mentioned in the embodiments can be combined in any way. This application is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. An underwater submersible based on electrochemical gas control, characterized in that, Includes the mothership, silent buoyancy adjustment unit, hydrofoil power unit, and control and communication unit; Multiple silent buoyancy adjustment units are distributed around the bottom outer perimeter of the mothership. Each silent buoyancy adjustment unit includes a reaction chamber, an electrolytic electrode, an ionic liquid storage chamber, a gas permeation membrane, and a flexible airbag. The reaction chamber is fixed to the mothership and connected to the flexible airbag through multiple air vents. The ionic liquid storage chamber is installed inside the reaction chamber and contains an ionic liquid with CO2 release and absorption capabilities. The ionic liquid storage chamber has openings and is covered by the gas permeation membrane. The electrolytic electrode... The positive and negative electrodes of the electrolytic electrode are inserted into the ionic liquid. The control and communication unit controls the direction and intensity of the electric field applied to the positive and negative electrodes of the electrolytic electrode to achieve electrochemical reversible absorption and release of CO2: when a reducing electric field is applied to the electrolytic electrode, CO2 in the ionic liquid is released into the flexible gasbag, increasing the volume of the flexible gasbag and thus increasing buoyancy to make the mothership float; when an oxidizing electric field is applied to the electrolytic electrode, CO2 in the flexible gasbag is absorbed by the ionic liquid, decreasing the volume of the flexible gasbag and thus decreasing buoyancy to make the mothership submerge. The hydrofoil power unit includes a gliding hydrofoil, a water-lifting hydrofoil, and a propulsion unit. The two gliding hydrofoils are symmetrically arranged on both sides of the stern of the mothership and can be folded and retracted relative to the mothership. The two water-lifting hydrofoils are respectively arranged in the middle and at the bottom of the stern of the mothership. The propulsion unit is mounted on the water-lifting hydrofoil located at the bottom of the stern of the mothership. The ionic liquid is a 1-butyl-3-methylimidazolium tetrafluoroborate solution pre-dissolved with CO2.

2. The underwater submersible according to claim 1, characterized in that, This underwater vehicle has two modes: high-speed surface navigation and silent underwater navigation. In the high-speed water surface navigation mode, the gliding hydrofoil is in a folded state. The control and communication unit generates lift by adjusting the angle of attack of the water surface lifting hydrofoil, so that part of the mothership leaves the water surface, which significantly reduces frictional drag and wave-making drag. The propulsion unit enables the mothership to travel at high speed and over long distances. Upon reaching the mission area, the underwater vehicle switches to underwater gliding mode. At this time, the control and communication unit shuts down the thrusters and controls the deployment of the gliding hydrofoils. Simultaneously, it controls the electrolytic electrodes to periodically apply reducing and oxidizing electric fields, enabling the mothership to advance by relying on the horizontal component of the lift generated by the gliding hydrofoils during the periodic "dive-surface" process, thus achieving continuous and silent underwater gliding.

3. The underwater submersible according to claim 1, characterized in that, The electrochemical reversible adsorption and desorption process of CO2 achieved by the 1-butyl-3-methylimidazolium tetrafluoroborate solution is as follows: When the electrolytic electrode applies a reducing electric field to the ionic liquid, the cations in the ionic liquid gain electrons at the cathode and are reduced to neutral molecules, which greatly reduces their ability to bind CO2. This causes the pre-dissolved CO2 gas to be rapidly released. The released CO2 gas is discharged into the flexible gasbag through the gas permeation membrane, which reduces the relative density of the mothership to generate positive buoyancy, thereby propelling the mothership to float. Conversely, when the electrolytic electrode applies an oxidation electric field to the ionic liquid, the neutral molecules in the ionic liquid lose electrons at the anode and are oxidized back to their original ionic state. At this time, their ability to bind CO2 is enhanced again, and they begin to extract CO2 gas from the flexible gasbag. This absorption process reduces the relative density of the mothership to form negative buoyancy, thereby prompting the mothership to dive.

4. The underwater submersible according to claim 3, characterized in that, The control and communication unit is equipped with a PID controller, which is electrically connected to the electrolysis electrode. By precisely controlling the voltage magnitude and duration of the electric field applied to the electrolysis electrode, the release and absorption of CO2 can be accurately regulated, thereby achieving millinewton-level fine-tuning of net buoyancy.

5. The underwater submersible according to claim 4, characterized in that, The PID controller is pre-loaded with the following mathematical models for ideal gas states and mathematical models for CO2 absorption and release by ionic liquids: In the formula, This represents the volume change of CO2 gas. n CO2 This refers to the molar amount of CO2 released. R It is the ideal gas constant; T It is the temperature of the gas; p It is the pressure of the gas; I The current released by the electrolytic electrodes; t The duration for which an electric field is applied to the electrolytic electrodes; η For current efficiency; z The number of electrons in the reaction; F It is Faraday's constant; The volume of CO2 gas required to produce a specific change in buoyancy can be accurately calculated using the mathematical model described above. This allows for the reverse calculation of the magnitude and duration of the electric field applied to the electrolytic electrode, thus enabling precise fine-tuning of the net buoyancy.

6. The underwater submersible according to claim 1, characterized in that, It also includes an ROV, and an ROV deployment and retrieval compartment is provided at the stern of the mother vessel. The ROV deployment and retrieval compartment is equipped with a deployment and retrieval mechanism and a wireless charging coil assembly. The ROV is placed in the ROV deployment and retrieval compartment and is connected to the mother vessel through an optical fiber composite cable and the deployment and retrieval mechanism.

7. The underwater submersible according to claim 2, characterized in that, The dynamics of the high-speed surface navigation mode described above can be described as a typical lift-supported motion mechanism, and its dynamic model can be expressed as: In the formula, L For the lift of the mothership; ρ Density of water; U The speed of the mothership; S The airfoil planar area for water-lifting hydrofoils; C L This is the lift coefficient.

8. The underwater submersible according to claim 2, characterized in that, The dynamic model of the underwater gliding and submersible navigation mode can be expressed as follows: In the formula, F net The net buoyancy force on the mother ship; m For the mass of the mothership; g It is the acceleration due to gravity; ρ Density of water; V To create space for the mothership.

9. The underwater submersible according to any one of claims 1 to 8, characterized in that, The control and communication unit consists of an embedded processor. The control unit, combined with an inertial measurement unit, depth sensor, temperature sensor, and current meter, enables autonomous state perception and decision-making. The control algorithm adopts a hierarchical architecture, with the upper layer being the task planning layer and the lower layer being the attitude and execution layer. The communication unit uses a satellite link for remote communication on the water surface and transmits via acoustic modulation underwater.

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