Method and device for measuring the height of flight of a hydrofoil craft using capacitive sensors

Abstract

The application relates to a method and device for measuring wing height of a hydrofoil craft by using a capacitive sensor. The method comprises: converting a capacitive change signal of the capacitive sensor into a corresponding frequency change amount; wherein the capacitive sensor is installed at the end of a hydrofoil support rod and is used for generating the capacitive change signal based on water level change; inputting the frequency change amount into a draft depth model to obtain an actual draft depth; and calculating target wing height data according to a known position relationship of the hydrofoil support rod relative to a ship body based on the actual draft depth. The method can provide high-precision and real-time measurement of the wing height of the hydrofoil craft by measuring the wing height of the hydrofoil craft by using the capacitive sensor, avoid interference of environmental factors on the measurement accuracy compared with an ultrasonic sensor, improve the wing height measurement frequency and stability, and significantly enhance the stability and safety of the hydrofoil craft navigation.

Description

Technical Field

[0001] This invention belongs to the field of computer and communication technology, and in particular relates to a method and apparatus for measuring the wing altitude of a hydrofoil using a capacitive sensor. Background Technology

[0002] In the field of marine navigation, hydrofoils are vessels that use unique hydrofoils as their primary power structure. During navigation, accurately measuring the takeoff altitude of a hydrofoil is crucial to ensuring its stability and efficiency. Traditional methods for measuring the takeoff altitude of hydrofoils often rely on ultrasonic sensors. Ultrasonic waves are emitted from a module, reflected off the water surface, and then received by the module, which then processes the data to obtain the altitude. However, this method is limited by the speed of sound, resulting in long measurement times per measurement and difficulty in achieving high-frequency measurements. Furthermore, the actual water surface is not an ideal plane; the presence of waves and spray prevents ultrasonic waves from reflecting at ideal angles, easily causing disordered altitude measurement information and even yielding erroneous data, thus affecting the hydrofoil's navigation control and safety. Summary of the Invention

[0003] Therefore, it is necessary to provide a method for measuring the wing altitude of a hydrofoil using a capacitive sensor to address the aforementioned technical problems, thereby improving the frequency, accuracy, and stability of wing altitude measurement and enhancing the dynamic control and navigation stability of the hydrofoil.

[0004] In a first aspect, this application provides a method for measuring the wing altitude of a hydrofoil using a capacitive sensor, the method comprising:

[0005] The capacitance change signal from the capacitance sensor is converted into a corresponding frequency change; the capacitance sensor is installed at the end of the hydrofoil support rod and is used to generate a capacitance change signal based on water level changes.

[0006] Input the frequency change into the draft model to obtain the actual draft.

[0007] Based on the actual draft, the target wing altitude data is calculated according to the known positional relationship between the hydrofoil support rod and the hull.

[0008] In one embodiment, the formula for calculating the target wing altitude data based on the draft and the known positional relationship of the hydrofoil support rod relative to the hull is as follows:

[0009] H = L1 + (Lh)

[0010] Where H is the target wing altitude data; L1 is the distance from the hull to the top of the capacitive sensor; L is the vertical length of the capacitive sensor; and h is the actual draft.

[0011] In one embodiment, converting the capacitance change signal of the capacitance sensor into a corresponding frequency change includes:

[0012] The capacitance value is calculated based on the capacitance change signal through a capacitance detection circuit. The capacitance detection circuit includes a constant current source, a capacitor, a switch, a reference voltage source, and a comparator. The constant current source is connected to the sensing electrode of the capacitor. The capacitor includes a sensing electrode connected to system ground. The switch is connected in parallel with the capacitor. The reference voltage source is connected to the first input terminal of the comparator. The system ground terminal of the capacitor is connected to the second input terminal of the comparator. The output terminal of the comparator outputs a PWM signal.

[0013] The capacitance value is converted into a corresponding frequency change through a frequency conversion circuit.

[0014] In one embodiment, the formula for calculating the capacitance value is:

[0015] C = (I s *△t) / V ref

[0016] Among them, I s The constant current value provided by the constant current source, Δt is the time interval between the switch being turned off and the comparator outputting a high-level signal, during which the constant current source charges the capacitor, V. ref A fixed voltage value set for the reference voltage source.

[0017] In one embodiment, the method further includes:

[0018] Acquire multiple hull height data points, which are used to characterize the distance of different hull positions relative to the water surface;

[0019] The ship's height data is preprocessed and then fused using data fusion technology to obtain the fused ship's height.

[0020] The fused hull height is smoothed and filtered to obtain the actual hull height, and the deviation between the actual hull height data and the target wing height data is calculated.

[0021] Control commands are generated based on the deviation height, and these commands are used to instruct the control hull to reach the target wing altitude data.

[0022] In one embodiment, the method further includes:

[0023] A dielectric constant-capacitance relationship model was constructed based on experimental data and corresponding capacitance measurement data under different water conditions. The experimental data included water salinity, water temperature, and water pH.

[0024] Input the capacitance value into the dielectric constant-capacitance relationship model to obtain the estimated dielectric constant of the current water area;

[0025] The actual draft is corrected based on the estimated dielectric constant to obtain the corrected draft.

[0026] Based on the known positional relationship between the hydrofoil support rod and the hull, the corrected target wing altitude data is calculated using the corrected draft, and the corrected target wing altitude data is determined as the target wing altitude data.

[0027] Secondly, this application also provides a system for measuring the wing altitude of a hydrofoil using a capacitive sensor, the system comprising:

[0028] The frequency conversion module is used to convert the capacitance change signal from the capacitance sensor into a corresponding frequency change; wherein, the capacitance sensor is installed at the end of the hydrofoil support rod and is used to generate the capacitance change signal based on the water level change.

[0029] The draft calculation module is used to input the frequency change into the draft model to obtain the actual draft.

[0030] The wing altitude calculation module is used to calculate the target wing altitude data based on the actual draft and the known positional relationship between the hydrofoil support rod and the hull.

[0031] Thirdly, this application also provides a device for measuring the wing altitude of a hydrofoil using a capacitive sensor. The device includes a capacitive sensor installed at the end of the hydrofoil support rod, a draft conversion device, and a hull flight altitude conversion unit. The hull flight altitude conversion unit is located in the central controller of the hydrofoil, and the sensing electrode of the capacitive sensor is immersed in the water area where the hydrofoil is currently located.

[0032] The capacitance sensor includes a capacitance detection circuit, which includes a constant current source, a capacitor, a switch, a reference voltage source, and a comparator. The constant current source is connected to the sensing electrode of the capacitor. The capacitor includes a sensing electrode and a system ground. The switch is connected in parallel with the capacitor. The reference voltage source is connected to the first input terminal of the comparator. The system ground terminal of the capacitor is connected to the second input terminal of the comparator. The output terminal of the comparator outputs a PWM signal.

[0033] The draft conversion device is used to convert the capacitance change signal of the capacitance sensor into a corresponding frequency change.

[0034] The draft conversion device is used to input the frequency change into the draft model to obtain the actual draft, and generate the actual draft signal based on the actual draft.

[0035] The hull flight altitude conversion unit is used to calculate the target wing flight altitude data based on the actual draft and the known positional relationship between the hydrofoil support rod and the hull, and then control the takeoff altitude through the central controller.

[0036] In one embodiment, the device further includes a data transmission device for receiving the actual draft signal, converting the actual draft signal into a differential CAN signal or an RS485 signal, and transmitting it to the ship's flight altitude conversion unit through the corresponding physical interface.

[0037] Fourthly, this application also provides a computer-readable storage medium having a computer program stored thereon, wherein the computer program, when executed by a processor, implements the steps of the method of any one of the first aspects.

[0038] The aforementioned method, apparatus, system, and readable storage medium for measuring the wing altitude of a hydrofoil using a capacitive sensor firstly converts the capacitance change signal of the capacitive sensor into a frequency change signal, which is easier to transmit and process. This effectively reduces interference during signal transmission, improves signal stability and reliability, and provides more accurate water level change data, thus providing high-quality raw signals for subsequent calculations. The capacitive sensor, installed at the end of the hydrofoil support rod, senses water level changes and outputs a corresponding capacitance change signal. This process converts a physical quantity into a measurable electrical signal, providing a valid basis for calculating the actual draft of the hydrofoil. Secondly, by inputting the obtained frequency change into a draft model, the relationship between the capacitance signal change and the draft is quantified, further improving the accuracy of draft measurement and providing necessary parameter support for subsequent wing altitude calculations. Finally, based on the actual draft output by the model and the known positional relationship between the hydrofoil support rod and the hull, stable target wing altitude data can be calculated under complex water surface conditions, thereby ensuring the navigation stability and safety of the hydrofoil.

[0039] Compared with traditional ultrasonic sensor measurement methods, this method, through the organic combination of capacitive sensors, signal conversion, draft calculation, and geometric relationship operations, has the following advantages:

[0040] 1. Significantly increased frequency for wing altitude measurement. In traditional ultrasonic methods, the highest frequency for ultrasonic measurement is typically below 40Hz due to the speed of sound. However, this method, combined with a capacitive sensor, is not limited by the speed of sound, and the capacitance value changes rapidly with water level, allowing for a measurement frequency of at least 150Hz. This significantly increases the frequency of flight altitude measurement, providing more detailed and higher-frequency data output in complex water surface environments. This facilitates more accurate tracking and adjustment of wing altitude, thereby improving flight stability and safety.

[0041] 2. Significantly improved accuracy of hydrofoil altitude measurement. Due to the unevenness of the water surface, various waves can alter the reflection direction of ultrasonic waves, causing ultrasonic sensors to fail to obtain data or obtain incorrect altitude data. However, in this method, the effect of water waves on the capacitive sensor is limited to changes in the wave height. The capacitance value follows the slight fluctuations of the water waves in real time, fundamentally avoiding abnormal data caused by changes in reflection direction. This further improves the accuracy of hydrofoil altitude measurement, effectively reducing potential risks caused by inaccurate hydrofoil altitude measurement and providing strong support for the safe and stable navigation of hydrofoils. Attached Figure Description

[0042] To more clearly illustrate the technical solutions in the embodiments or related technologies of this application, the accompanying drawings used in the description of the embodiments or related technologies will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0043] Figure 1 A schematic flowchart of a method for measuring the wing altitude of a hydrofoil using a capacitive sensor, provided as an exemplary embodiment of the present invention;

[0044] Figure 2 A capacitance detection circuit diagram is provided as an exemplary embodiment of the present invention;

[0045] Figure 3 This is a schematic diagram of a system structure for measuring the wing altitude of a hydrofoil using a capacitive sensor, as an exemplary embodiment of the present invention. Detailed Implementation

[0046] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0047] In one embodiment, such as Figure 1 As shown, a method for measuring the wing altitude of a hydrofoil using a capacitive sensor is provided. This embodiment illustrates the application of this method to a terminal. It is understood that this method can also be applied to a server, and to a system including both a terminal and a server, and implemented through interaction between the terminal and the server. In this embodiment, the method includes the following steps:

[0048] S101: Converts the capacitance change signal from the capacitance sensor into a corresponding frequency change; wherein, the capacitance sensor is installed at the end of the hydrofoil support rod and is used to generate a capacitance change signal based on water level changes.

[0049] When a hydrofoil travels on water, the hydrofoil support rod is at a critical position where the hydrofoil contacts the water. Schematic, a capacitive sensor, which can be elongated and mounted at the end of the support rod, can be a copper rod as the sensing electrode, encased in an insulating material and placed inside a cylindrical container connected to the water surface. Based on the fundamental principle of capacitance, changes in water level cause changes in the dielectric constant or electrode spacing within the sensor, resulting in a change in capacitance and generating a capacitance change signal. However, transmitting and processing this capacitance change signal presents certain challenges. To facilitate subsequent analysis and calculation, specific circuit designs or signal processing techniques, such as combining an oscillating circuit, can be used to convert the capacitance change signal into a corresponding frequency signal, i.e., a frequency change. Frequency signals have stronger anti-interference capabilities, effectively reducing signal loss and distortion during transmission, ensuring accurate and stable transmission to the subsequent data processing unit, and providing a reliable data foundation for precise measurement of hydrofoil altitude.

[0050] S102: Input the frequency change into the draft model to obtain the actual draft.

[0051] Specifically, the draft model is constructed based on extensive experimental data and theoretical research, reflecting the intrinsic relationship between frequency changes and actual draft. When the frequency change enters the draft model, the frequency data is first filtered, organized, and corrected according to pre-set rules to eliminate potential measurement errors or interference noise. A specific algorithm maps the frequency value to the corresponding draft value, thus obtaining the actual draft. This provides an accurate intermediate data foundation for subsequent calculations, ensuring the consistency and accuracy of the measurement. Illustratively, in this process, for a hydrofoil, since the capacitive sensor is installed at the end of the hydrofoil support rod, the actual draft can be understood as the vertical distance from the end of the capacitive sensor entering the water to the water surface, i.e., the vertical depth of the hydrofoil hull submerged in the water, thus providing the relationship between the hydrofoil and the water surface.

[0052] S103: Based on the actual draft, calculate the target wing altitude data according to the known positional relationship between the hydrofoil support rod and the hull.

[0053] The positional relationship between the hydrofoil support rod and the hydrofoil boat hull is a predetermined geometric relationship. Illustratively, the positional relationship between the hydrofoil support rod and the hydrofoil boat hull can be obtained by considering the rod's installation position and angle on the hull, as well as its length, shape, and other geometric parameters. Furthermore, by constructing a spatial geometric model and calculating based on the actual draft, the target wing altitude data of the hydrofoil boat can be obtained. The target wing altitude data refers to the desired vertical distance from the hydrofoil boat hull to the water surface. Real-time monitoring of the target wing altitude helps operators adjust the hydrofoil boat's navigation status accordingly, ensuring optimal performance and improving navigation efficiency and safety.

[0054] In the aforementioned method for measuring the wing altitude of a hydrofoil using a capacitive sensor, the capacitance change signal is acquired and processed in real time by a capacitive sensor installed at the end of the hydrofoil support rod. Compared to traditional ultrasonic sensor measurement methods, this avoids the influence of environmental factors such as sound speed, thus facilitating accurate measurement of the hydrofoil's wing altitude. Furthermore, converting the capacitance change signal into a frequency change effectively reduces interference during signal transmission, improving signal stability and reliability. By inputting the frequency change into a draft model for analysis, the frequency change is transformed into meaningful draft data, further enhancing the scientific rigor and reliability of the data processing. Finally, combining the actual draft with geometric calculations based on the known relative positional relationship between the hydrofoil support rod and the hull, the target wing altitude data is obtained. This not only improves the accuracy of the calculation but also provides crucial data support for the hydrofoil's flight control.

[0055] Compared to traditional ultrasonic sensor measurement methods, this method not only significantly improves the frequency and accuracy of wing altitude measurement, but also provides more stable and real-time target wing altitude data support in complex water environments, providing an important guarantee for the safe and stable operation of hydrofoils.

[0056] In one embodiment, the formula for calculating the target wing altitude data based on the draft and the known positional relationship of the hydrofoil support rod relative to the hull is as follows:

[0057] H = L1 + (Lh)

[0058] Where H is the target wing altitude data; L1 is the distance from the hull to the top of the capacitive sensor; L is the vertical length of the capacitive sensor; and h is the actual draft.

[0059] In the above formula, the distance L1 from the hull to the top of the capacitive sensor is a fixed value determined by the hydrofoil's structural design, and can represent the vertical distance from the preset reference point on the hull to the top of the capacitive sensor. The vertical length L of the capacitive sensor is a constant determined by factors such as the sensor's specifications and installation method. The actual draft h reflects the vertical distance from the end of the capacitive sensor submerged in the water to the water surface, i.e., the depth of the hull submerged in the water. Therefore, (Lh) in the formula can represent the length of the capacitive sensor above the water surface. By combining this with the distance L1 from the hull to the top of the capacitive sensor, the target wing altitude data H can be obtained.

[0060] In one embodiment, converting the capacitance change signal of the capacitance sensor into a corresponding frequency change includes:

[0061] The capacitance value is calculated based on the capacitance change signal through a capacitance detection circuit. The capacitance detection circuit includes a constant current source, a capacitor, a switch, a reference voltage source, and a comparator. The constant current source is connected to the sensing electrode of the capacitor. The capacitor includes a sensing electrode connected to system ground. The switch is connected in parallel with the capacitor. The reference voltage source is connected to the first input terminal of the comparator. The system ground terminal of the capacitor is connected to the second input terminal of the comparator. The output terminal of the comparator outputs a PWM signal.

[0062] The capacitance value is converted into a corresponding frequency change through a frequency conversion circuit.

[0063] Specifically, such as Figure 2 As shown, the constant current source is connected to the sensing electrode of the capacitor. Its function is to provide a constant current to the capacitor. According to the principle of capacitor charging, the change in charge is proportional to time, laying the foundation for subsequent calculation of the capacitance value. The capacitor includes the sensing electrode and system ground, and its capacitance value will change due to factors such as water level changes. A MOSFET (Metal-Oxide-Semiconductor Field-Effect Transistor) can be used as the switch, connected in parallel with the capacitor, and its on / off state is controlled by a switch control signal. When the switch is closed, the voltage on the capacitor drops rapidly to 0; when the switch is open, the constant current source begins to charge the capacitor, and the capacitor voltage rises. The periodic on / off switching of the switch causes the capacitor to continuously charge and discharge, thereby generating a measurable voltage change.

[0064] A reference voltage source is connected to the first input terminal of the comparator, providing a fixed reference voltage. This reference voltage is the standard by which the comparator determines the capacitor voltage. The system ground terminal of the capacitor is connected to the second input terminal of the comparator, which compares the capacitor voltage with the reference voltage. When the capacitor voltage is less than the reference voltage, the comparator outputs a low level; when the capacitor voltage is greater than the reference voltage, the comparator outputs a high level. The comparator outputs a PWM (Pulse Width Modulation) signal. High and low levels represent two states of the pulse, and the changes in the high and low levels of the PWM signal reflect the changes in the capacitor voltage, and thus the changes in the capacitance value. The switch control signal can be sent by the processing unit, which also sends the comparator output signal to the processing unit. The processing unit can then calculate the capacitance value based on the switch control signal and the comparator output signal. Finally, based on the capacitance-frequency characteristic relationship, such as in an LC oscillator circuit, the capacitance value can be converted into a corresponding frequency change for transmission.

[0065] In one embodiment, the formula for calculating the capacitance value is:

[0066] C = (I s *△t) / V ref

[0067] Among them, I s The constant current value provided by the constant current source, Δt is the time interval between the switch being turned off and the comparator outputting a high-level signal, during which the constant current source charges the capacitor, V. ref A fixed voltage value set for the reference voltage source.

[0068] Indicatively, the period and duty cycle of the PWM signal output by the comparator are closely related to the charging and discharging process of the capacitor. One cycle includes the entire process from the start of charging (switch open) to the voltage reaching the reference voltage (comparator output high level) and then to the capacitor discharging (switch closed). The capacitance value C can be calculated by measuring the period and high-level duration of the PWM signal to determine Δt.

[0069] In one embodiment, the method further includes:

[0070] Acquire multiple hull height data points, which are used to characterize the distance of different hull positions relative to the water surface;

[0071] The ship's height data is preprocessed and then fused using data fusion technology to obtain the fused ship's height.

[0072] The fused hull height is smoothed and filtered to obtain the actual hull height, and the deviation between the actual hull height data and the target wing height data is calculated.

[0073] Control commands are generated based on the deviation height, and these commands are used to instruct the control hull to reach the target wing altitude data.

[0074] After obtaining the target wing altitude data, the current wing altitude of the hydrofoil can be adjusted. During the adjustment process, the hull may experience variations in altitude relative to the water surface at different locations due to various factors such as uneven load distribution, currents, and waves. Multiple sensors can be used to acquire the distances of different hull positions relative to the water surface, resulting in multiple hull altitude data points. Furthermore, the collected hull altitude data can be preprocessed, such as removing outliers and normalizing the data. Data fusion methods, such as weighted averaging, Kalman filtering, and Bayesian estimation, can then be used to better monitor the actual altitude of various parts of the hydrofoil above the water, helping to avoid potential dangers caused by excessively low local altitudes.

[0075] Applying smoothing filters such as averaging or low-pass filtering to the obtained fused hull height can further remove high-frequency noise components from the data, making it smoother and more stable. Subtracting the actual hull height from the target wing flight height yields the deviation height. This deviation height represents the difference between the current hull height and the desired target wing flight height, and the magnitude and direction of the deviation height are used to generate corresponding control commands. For example, a positive deviation height may indicate that the hull is higher than the target wing flight height, requiring a reduction in hull height; a negative deviation height may indicate a need to increase hull height.

[0076] The control commands can be used by the central controller of the hydrofoil to control the angle of the hydrofoil, the power of the propeller, etc., to adjust the attitude and speed of the hull, so that the hull can reach the target wing height, thereby improving the navigation performance and stability of the hydrofoil.

[0077] In one embodiment, the method further includes:

[0078] A dielectric constant-capacitance relationship model was constructed based on experimental data and corresponding capacitance measurement data under different water conditions. The experimental data included water salinity, water temperature, and water pH.

[0079] Input the capacitance value into the dielectric constant-capacitance relationship model to obtain the estimated dielectric constant of the current water area;

[0080] The actual draft is corrected based on the estimated dielectric constant to obtain the corrected draft.

[0081] Based on the known positional relationship between the hydrofoil support rod and the hull, the corrected target wing altitude data is calculated using the corrected draft, and the corrected target wing altitude data is determined as the target wing altitude data.

[0082] To illustrate, the dielectric constant is a crucial parameter describing the electrical properties of water, typically used to reflect its response to an electric field. It is influenced not only by the water's chemical composition (such as salinity) and temperature but also by its physical state. Changes in the dielectric constant directly affect the measurements of capacitance sensors, potentially leading to inaccurate draft measurements. Therefore, to mitigate the impact of the dielectric constant, a dielectric constant-capacitance relationship model can be constructed based on experimental data and corresponding capacitance measurements under different water conditions, using a specific algorithm or function. By inputting the actual measured capacitance value into the established model, the dielectric constant of the current water area can be calculated. A correction function can be constructed based on the influence of the dielectric constant on draft to adjust the actual draft, obtaining a corrected draft that better reflects the current water conditions. Based on the known positional relationship of the hydrofoil support rod relative to the hull, using geometric principles and the corrected draft, a more accurate corrected wing altitude data is recalculated as the final target wing altitude data. This data more accurately reflects the wing altitude of the hydrofoil under current water conditions, providing a more reliable basis for subsequent navigation control and performance evaluation.

[0083] Based on the same inventive concept, such as Figure 3 As shown in the figure, this application embodiment also provides a system 300 for measuring the wing altitude of a hydrofoil using a capacitive sensor. The system includes:

[0084] The frequency conversion module 301 is used to convert the capacitance change signal of the capacitance sensor into a corresponding frequency change; wherein, the capacitance sensor is installed at the end of the hydrofoil support rod and is used to generate the capacitance change signal based on the water level change.

[0085] The draft calculation module 302 is used to input the frequency change into the draft model to obtain the actual draft.

[0086] The wing altitude calculation module 303 is used to calculate the target wing altitude data based on the actual draft and the known positional relationship between the hydrofoil support rod and the hull.

[0087] The system uses a frequency conversion module 301 to convert the capacitance change signal from the capacitive sensor into a corresponding frequency change, making the signal easier to process and analyze, and providing stronger anti-interference capabilities and higher transmission stability. Furthermore, the capacitive sensor, installed at the end of the hydrofoil support rod, generates a capacitance change signal due to water level changes, achieving accurate, stable, and efficient water level change detection. This provides a reliable data foundation for subsequent draft calculation and hydrofoil altitude adjustment. The frequency change output from the frequency conversion module 301 is then input into the draft model in the draft calculation module 302 to obtain the actual draft. This process utilizes the relationship between the frequency change and the draft model to convert the physical signal into a real physical quantity related to the hydrofoil's draft—the actual draft. This result reflects the hydrofoil's draft in its current state, providing crucial information for assessing its navigation status.

[0088] The hydrofoil altitude calculation module 303 converts the actual draft into target hydrofoil altitude data based on geometric principles and the known positional relationship between the hydrofoil support rod and the hull. This data helps operators better understand the hydrofoil's flight status, ensuring it navigates at the optimal altitude and further improving navigation efficiency and safety.

[0089] Furthermore, the calculation formula for calculating the target wing altitude data in the wing altitude calculation module 303 based on the draft and the known positional relationship between the hydrofoil support rod and the hull is as follows:

[0090] H = L1 + (Lh)

[0091] Where H is the target wing altitude data; L1 is the distance from the hull to the top of the capacitive sensor; L is the vertical length of the capacitive sensor; and h is the actual draft.

[0092] Furthermore, the frequency conversion module 301 includes:

[0093] The capacitance calculation subunit is used to calculate the capacitance value based on the capacitance change signal through the capacitance detection circuit. The capacitance detection circuit includes a constant current source, a capacitor, a switch, a reference voltage source, and a comparator. The constant current source is connected to the sensing electrode of the capacitor. The capacitor includes a sensing electrode connected to the system ground. The switch is connected in parallel with the capacitor. The reference voltage source is connected to the first input terminal of the comparator. The system ground terminal of the capacitor is connected to the second input terminal of the comparator. The output terminal of the comparator outputs a PWM signal.

[0094] The capacitor conversion subunit is used to convert the capacitance value into a corresponding frequency change through a frequency conversion circuit.

[0095] Furthermore, the formula for calculating the capacitance value is as follows:

[0096] C = (I s *△t) / V ref

[0097] Among them, I s The constant current value provided by the constant current source, Δt is the time interval between the switch being turned off and the comparator outputting a high-level signal, during which the constant current source charges the capacitor, V. ref A fixed voltage value set for the reference voltage source.

[0098] Furthermore, the system also includes a wing altitude control module for:

[0099] Acquire multiple hull height data points, which are used to characterize the distance of different hull positions relative to the water surface;

[0100] The ship's height data is preprocessed and then fused using data fusion technology to obtain the fused ship's height.

[0101] The fused hull height is smoothed and filtered to obtain the actual hull height, and the deviation between the actual hull height data and the target wing height data is calculated.

[0102] Control commands are generated based on the deviation height, and these commands are used to instruct the control hull to reach the target wing altitude data.

[0103] Furthermore, the system also includes a wing altitude correction module for:

[0104] A dielectric constant-capacitance relationship model was constructed based on experimental data and corresponding capacitance measurement data under different water conditions. The experimental data included water salinity, water temperature, and water pH.

[0105] Input the capacitance value into the dielectric constant-capacitance relationship model to obtain the estimated dielectric constant of the current water area;

[0106] The actual draft is corrected based on the estimated dielectric constant to obtain the corrected draft.

[0107] Based on the known positional relationship between the hydrofoil support rod and the hull, the corrected target wing altitude data is calculated using the corrected draft, and the corrected target wing altitude data is determined as the target wing altitude data.

[0108] In an exemplary embodiment, this application also provides a device for measuring the wing altitude of a hydrofoil using a capacitive sensor. The device includes a capacitive sensor installed at the end of the hydrofoil support rod, a draft conversion device, and a hull flight altitude conversion unit. The hull flight altitude conversion unit is located in the central controller of the hydrofoil, and the sensing electrode of the capacitive sensor is immersed in the water area where the hydrofoil is currently located.

[0109] The capacitance sensor includes a capacitance detection circuit, which includes a constant current source, a capacitor, a switch, a reference voltage source, and a comparator. The constant current source is connected to the sensing electrode of the capacitor. The capacitor includes a sensing electrode and a system ground. The switch is connected in parallel with the capacitor. The reference voltage source is connected to the first input terminal of the comparator. The system ground terminal of the capacitor is connected to the second input terminal of the comparator. The output terminal of the comparator outputs a PWM signal.

[0110] The draft conversion device is used to convert the capacitance change signal of the capacitance sensor into a corresponding frequency change.

[0111] The draft conversion device is used to input the frequency change into the draft model to obtain the actual draft, and generate the actual draft signal based on the actual draft.

[0112] The hull flight altitude conversion unit is used to calculate the target wing flight altitude data based on the actual draft and the known positional relationship between the hydrofoil support rod and the hull, and then control the takeoff altitude through the central controller.

[0113] In one exemplary embodiment, the present invention also provides a computer-readable storage medium storing a computer program thereon. When executed by a processor, the computer program implements the steps of a method for measuring the wing altitude of a hydrofoil using a capacitive sensor, as described in this application. The computer-readable storage medium may include: read-only memory (ROM), random access memory (RAM), solid-state drive (SSD), or optical disk, etc. The random access memory may include resistive random access memory (ReRAM) and dynamic random access memory (DRAM). The above embodiments merely illustrate several implementation methods of the embodiments of this application, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the patent application. It should be noted that those skilled in the art can make several modifications and improvements without departing from the concept of the embodiments of this application, and these all fall within the protection scope of the embodiments of this application.

Claims

1. A method for measuring the wing altitude of a hydrofoil using a capacitive sensor, characterized in that, The method includes: The capacitance change signal from the capacitance sensor is converted into a corresponding frequency change; wherein the capacitance sensor is installed at the end of the hydrofoil support rod and is used to generate a capacitance change signal based on water level changes. Input the frequency change into the draft model to obtain the actual draft. Based on the actual draft, the target wing altitude data is calculated according to the known positional relationship between the hydrofoil support rod and the hull. The process of converting the capacitance change signal of the capacitance sensor into a corresponding frequency change includes: The capacitance value is calculated based on the capacitance change signal by a capacitance detection circuit, which includes a constant current source, a capacitor, a switch, a reference voltage source, and a comparator. The constant current source is connected to the sensing electrode of the capacitor, the capacitor includes a sensing electrode connected to system ground, the switch is connected in parallel with the capacitor, the reference voltage source is connected to the first input terminal of the comparator, the system ground terminal of the capacitor is connected to the second input terminal of the comparator, and the output terminal of the comparator outputs a PWM signal. The capacitance value is converted into the corresponding frequency change through a frequency conversion circuit. The formula for calculating the capacitance value is as follows: C=(I s *△t) / V ref Among them, I s The constant current value provided by the constant current source, Δt is the time interval from when the switch is turned off to when the comparator outputs a high-level signal, during which the constant current source charges the capacitor, V ref A fixed voltage value is set for the reference voltage source.

2. The method according to claim 1, characterized in that, The formula for calculating the target wing altitude data based on the draft and the known positional relationship between the hydrofoil support rod and the hull is as follows: H = L1 + (Lh) Wherein, H is the target wing altitude data; L1 is the distance from the hull to the top of the capacitive sensor; L is the vertical length of the capacitive sensor; and h is the actual draft.

3. The method according to claim 1, characterized in that, The method further includes: Multiple hull height data are acquired, which are used to characterize the distance of different positions of the hull relative to the water surface; The hull height data is preprocessed and then fused using data fusion technology to obtain the fused hull height. The fused hull height is smoothed and filtered to obtain the actual hull height, and the deviation between the actual hull height data and the target wing height data is calculated. Based on the deviation height, a control command is generated, which is used to instruct the hull to reach the target wing altitude data.

4. The method according to claim 1, characterized in that, The method further includes: A dielectric constant-capacitance relationship model was constructed based on experimental data and corresponding capacitance measurement data under different water conditions. The experimental data included water salinity, water temperature, and water pH. The capacitance value is input into the dielectric constant-capacitance relationship model to obtain an estimated value of the dielectric constant of the current water area; The actual draft is corrected based on the estimated dielectric constant to obtain the corrected draft. Based on the known positional relationship of the hydrofoil support rod relative to the hull, the corrected target wing altitude data is calculated based on the corrected draft, and the corrected target wing altitude data is determined as the target wing altitude data.

5. A system for measuring the wing altitude of a hydrofoil using a capacitive sensor, characterized in that, The system is used to implement the method according to any one of claims 1 to 4, the system comprising: A frequency conversion module is used to convert the capacitance change signal of the capacitance sensor into a corresponding frequency change; wherein, the capacitance sensor is installed at the end of the hydrofoil support rod and is used to generate a capacitance change signal based on water level changes. The draft calculation module is used to input the frequency change into the draft model to obtain the actual draft. The wing altitude calculation module is used to calculate the target wing altitude data based on the actual draft and the known positional relationship between the hydrofoil support rod and the hull.

6. A device for measuring the wing altitude of a hydrofoil using a capacitive sensor, characterized in that, The device is used to implement the method according to any one of claims 1 to 4. The device includes a capacitive sensor installed at the end of the hydrofoil support rod, a draft conversion device and a hull flight altitude conversion unit. The hull flight altitude conversion unit is located in the central controller of the hydrofoil, and the sensing electrode of the capacitive sensor is immersed in the water area where the hydrofoil is currently located. The capacitance sensor includes a capacitance detection circuit, which includes a constant current source, a capacitor, a switch, a reference voltage source, and a comparator. The constant current source is connected to the sensing electrode of the capacitor. The capacitor includes a sensing electrode connected to system ground. The switch is connected in parallel with the capacitor. The reference voltage source is connected to the first input terminal of the comparator. The system ground terminal of the capacitor is connected to the second input terminal of the comparator. The output terminal of the comparator outputs a PWM signal. The draft conversion device is used to convert the capacitance change signal of the capacitance sensor into a corresponding frequency change. The draft conversion device is used to input the frequency change into the draft model to obtain the actual draft, and generate an actual draft signal based on the actual draft. The hull flight altitude conversion unit is used to calculate the target wing flight altitude data based on the actual draft and the known positional relationship between the hydrofoil support rod and the hull, and to control the takeoff altitude through the central controller.

7. The apparatus according to claim 6, characterized in that, The device also includes a data transmission device for receiving the actual draft signal, converting the actual draft signal into a differential CAN signal or an RS485 signal, and transmitting it to the ship's flight altitude conversion unit through the corresponding physical interface.

8. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by a processor, it implements the steps of the method according to any one of claims 1 to 4.

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