Electro-wetting surface regulation system, method and vehicle

Abstract

This application discloses an electrowetting surface control system, method, and vehicle, belonging to the field of automotive technology. The system uses a vehicle speed sensor to acquire real-time driving speed; a control module determines a target voltage amplitude based on the real-time driving speed and sends it to a voltage drive module; the voltage drive module applies a voltage corresponding to the target voltage amplitude to a transparent conductive electrode layer; the transparent electrowetting glass panel includes a glass substrate, a transparent conductive electrode layer, a dielectric layer, and a hydrophobic functional layer stacked sequentially, wherein the transparent conductive electrode layer and the dielectric layer form an insulating capacitor structure. When a voltage is applied to the transparent conductive electrode layer, the electrowetting effect of the insulating capacitor structure adjusts the contact angle between the hydrophobic functional layer and water droplets, thereby regulating the wetting state. This application maintains a hydrophobic state to assist drainage during high-speed driving, a hydrophilic state to assist cleaning during low-speed driving, and a moderately hydrophilic state to achieve a balance during medium-speed driving.

Description

Technical Field

[0001] This application relates to the field of automotive technology, and in particular to an electrowetting surface control system, method, and vehicle. Background Technology

[0002] During vehicle operation, the airflow velocity on the windshield surface is positively correlated with vehicle speed. This drastic change in airflow shear force caused by variations in vehicle speed has a decisive impact on the self-cleaning properties of the glass surface (such as rainwater rolling off, stain adhesion, and detergent distribution). Specifically: High-speed driving conditions: The strong airflow shearing force is beneficial for blowing rainwater and loose stains away from the glass surface, but it also easily blows away the detergent, making it difficult for it to adhere effectively to the glass surface and reducing cleaning efficiency.

[0003] At low speeds or when stationary: the airflow shear force is weak, and rainwater easily accumulates on the glass surface to form a water film or large water droplets, which seriously affects the driver's visibility; although the washer fluid is not easily blown away, it is easy to flow, making it difficult to achieve efficient use.

[0004] Currently, the surface wettability of self-cleaning technologies applied to vehicle windshields, such as superhydrophobic or hydrophilic coatings, cannot be changed once it is fixed. For example, superhydrophobic surfaces have excellent drainage performance under high-speed driving conditions, but under low-speed driving or stationary conditions, droplets may adhere and fail to roll off, potentially causing blurred vision. On the other hand, hydrophilic surfaces help the detergent spread and clean under low-speed driving or stationary conditions, but under high-speed driving conditions, the detergent is easily blown away by airflow, resulting in waste and cleaning failure. Summary of the Invention

[0005] This application provides an electrowetting surface control system, method, and vehicle to solve the problem that the wettability of a windshield surface cannot be dynamically adjusted according to vehicle speed, making it difficult to simultaneously achieve high-speed drainage and low-speed cleaning. The technical solution is as follows: According to a first aspect of this application, an electrowetting surface control system is provided, the system comprising: a vehicle speed sensor, a voltage driving module, a control module, and a transparent electrowetting glass panel; The vehicle speed sensor is used to obtain the real-time driving speed of the vehicle; The control module is connected to the vehicle speed sensor and the voltage drive module respectively, and is used to determine the target voltage amplitude according to the real-time driving speed and send the target voltage amplitude to the voltage drive module; The voltage driving module is electrically connected to the transparent conductive electrode layer in the transparent electrowetting glass panel, and is used to apply a voltage corresponding to the target voltage amplitude to the transparent conductive electrode layer; The transparent electrowetting glass panel includes a glass substrate, a transparent conductive electrode layer, a dielectric layer, and a hydrophobic functional layer stacked sequentially. The transparent conductive electrode layer and the dielectric layer form an insulating capacitor structure. When a voltage is applied to the transparent conductive electrode layer, the electrowetting effect of the insulating capacitor structure adjusts the contact angle between the hydrophobic functional layer and the water droplet, thereby adjusting the wetting state of the surface of the transparent electrowetting glass panel.

[0006] In one possible implementation, the control module is further configured to: When the real-time driving speed is greater than the first preset threshold, a target voltage amplitude less than the first voltage threshold is determined so that the wetting state of the transparent electrowetting glass panel surface is a hydrophobic state. When the real-time driving speed is less than the second preset threshold, a target voltage amplitude greater than the second voltage threshold is determined so that the wetting state of the transparent electrowetting glass panel surface is a hydrophilic state. When the real-time driving speed is less than the first preset threshold and greater than the second preset threshold, the target voltage amplitude is determined based on the negative correlation between the voltage amplitude and the real-time driving speed.

[0007] In one possible implementation, the transparent conductive electrode layer comprises an electrode array formed by a plurality of independently controllable electrode units; The control module is also used to determine a uniform target voltage amplitude based on the real-time driving speed, and apply the uniform target voltage amplitude to each electrode unit through the voltage driving module.

[0008] In one possible implementation, the system further includes a detergent spraying module connected to the control module; The control module is also used to send a spraying command to the cleaning liquid spraying module when it is determined that the surface of the transparent electrowetting glass panel needs to be cleaned. The detergent spraying module is used to spray detergent onto the surface of the transparent electrowetting glass panel in response to the spraying command.

[0009] In one possible implementation, the control module is further configured to: When it is determined that the surface of the transparent electrowetting glass panel needs to be cleaned, the target voltage amplitude is determined according to the preset mapping relationship and the real-time driving speed, and the target voltage amplitude is sent to the voltage driving module. After determining that the voltage driving module applies a voltage corresponding to the target voltage amplitude to the transparent conductive electrode layer so that the surface of the transparent electrowetting glass panel is in a stable hydrophilic state, a spraying command is sent to the washing liquid spraying module.

[0010] In one possible implementation, the system further includes a wiper module connected to the control module; The control module is also used to send a wiping command to the wiper module after sending a spray command to the wash liquid spray module. The wiper module is also configured to perform a wiping operation on the transparent electrowetting glass panel surface in response to the wiping command.

[0011] In one possible implementation, the control module is further configured to: Data on the effect of airflow on the spreading of detergent at different travel speeds were measured. Measure the adhesion efficiency data of the detergent under different wetting conditions; Measure the friction and wear data during windshield wiper operation; Based on the influence data, the adhesion efficiency data, and the friction and wear data, the mapping relationship between different driving speeds and different voltage amplitudes is determined.

[0012] According to a second aspect of this application, an electrowetting surface control method is provided for use in the electrowetting surface control system described above, the method comprising: Obtain the vehicle's real-time speed; The target voltage amplitude is determined based on the real-time driving speed; A voltage corresponding to the target voltage amplitude is applied to the transparent conductive electrode layer in the transparent electrowetting glass panel to adjust the wetting state of the transparent electrowetting glass panel surface.

[0013] According to a third aspect of this application, a computer-readable storage medium is provided, wherein at least one instruction is stored therein, the at least one instruction being loaded and executed by a processor to implement the electrowetting surface control method as described above.

[0014] According to a fourth aspect of this application, a vehicle is provided, the vehicle including the above-described electrowetting surface control device.

[0015] The beneficial effects of the technical solution provided in this application include at least the following: It achieves dynamic matching between the wettability of the transparent electrowetting glass panel surface and the driving speed (i.e., airflow intensity): at high speeds, it maintains a hydrophobic state to assist in drainage, and raindrops form spherical droplets that quickly roll off under the action of airflow, avoiding water film from affecting the driver's vision; at low speeds, it switches to a hydrophilic state to assist in cleaning, shortening cleaning time and reducing visual interference; at medium speeds, it is in a moderately hydrophilic state to achieve a balance, so that the self-cleaning performance reaches the optimal level across the entire vehicle speed range.

[0016] In a hydrophobic state, raindrops are easily blown away by airflow, significantly reducing the frequency of wiper usage. During cleaning, in a hydrophilic state, the detergent can quickly spread into a uniform liquid film on the glass panel surface, greatly improving adhesion efficiency. Furthermore, the uniform liquid film formed by the detergent has a lubricating effect, which can reduce friction during wiper wiping, reduce wear on wiper blades, and extend wiper life.

[0017] The transparent conductive electrode layer comprises an electrode array formed by multiple independent and controllable electrode units. A uniform target voltage amplitude can be applied to each electrode unit, thereby achieving uniform control of the wetting state of the entire glass surface. This eliminates the need for complex partition control circuits and multiple independent drive channels, making it easy to integrate into existing automotive glass manufacturing processes with limited cost increases. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments 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.

[0019] Figure 1 This is a structural block diagram of an electrowetting surface control system provided in one embodiment of this application; Figure 2 This is a flowchart of an embodiment of the electrowetting surface control method provided in this application. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the implementation methods of this application will be further described in detail below with reference to the accompanying drawings.

[0021] The following is an explanation of the terms used in this application.

[0022] Contact angle: When a droplet falls onto a solid surface, the angle formed at the solid-liquid interface through the liquid to the gas-liquid interface at the solid-liquid-gas three-phase junction is called the contact angle. The size of the contact angle reflects the degree of wetting of the solid surface by the liquid.

[0023] Hydrophobic state: When the contact angle is greater than 90°, the droplet is spherical, does not easily spread on the solid surface, and easily rolls off; this state is called hydrophobic. When the contact angle is greater than 150°, it is called superhydrophobic, exhibiting a typical "lotus effect". In this application, the contact angle corresponding to the hydrophobic state is ≥110°, the droplet is spherical on the glass surface, and is easily blown away under the action of high-speed airflow, making it suitable for high-speed driving conditions.

[0024] Hydrophilic state: When the contact angle is less than 90°, the droplet spreads on the solid surface; this state is called the hydrophilic state. When the contact angle is less than 10°, it is called the superhydrophilic state, where the droplet almost completely spreads into a film. In this application, the contact angle corresponding to the hydrophilic state is ≤90°, and the washing liquid or rainwater spreads into a uniform liquid film on the glass surface, which is not easily dispersed by airflow, making it suitable for low-speed driving or cleaning conditions.

[0025] Electrowetting regulation principle: When a voltage is applied to the transparent conductive electrode layer in the transparent electrowetting glass panel, the insulating capacitor structure formed by the transparent conductive electrode layer and the dielectric layer stores electrostatic energy, thereby changing the solid-liquid interfacial tension between the hydrophobic functional layer and the water droplet, thus continuously adjusting the contact angle. Specifically, the higher the applied voltage, the smaller the contact angle, and the more hydrophilic the surface becomes; when the applied voltage is zero or low, the contact angle is larger, and the surface remains hydrophobic. Therefore, this application can adjust the wetting state of the transparent electrowetting glass panel surface in real time according to vehicle speed, achieving dynamic switching between hydrophobic and hydrophilic states.

[0026] like Figure 1 The diagram illustrates a structural block diagram of an electrowetting surface control system according to an embodiment of this application. This electrowetting surface control method can be applied to vehicles. The electrowetting surface control system includes: a vehicle speed sensor 110, a voltage drive module 120, a control module 130, and a transparent electrowetting glass panel 140. The control module 130 is connected to both the vehicle speed sensor 110 and the voltage drive module 120, and the voltage drive module 120 is connected to the transparent electrowetting glass panel 140.

[0027] Vehicle speed sensor 110 is used to acquire the real-time driving speed of the vehicle. The vehicle speed sensor 110 can be a magnetoelectric vehicle speed sensor, a Hall effect vehicle speed sensor, or a photoelectric vehicle speed sensor. It is installed at the output shaft of the vehicle's transmission or at the wheel hub, and acquires the real-time driving speed at a sampling frequency of 10Hz. The real-time driving speed is then transmitted to the control module 130 via the Controller Area Network (CAN) bus.

[0028] The control module 130 is connected to the vehicle speed sensor 110 and the voltage drive module 120 respectively, and is used to determine the target voltage amplitude based on the real-time driving speed and send the target voltage amplitude to the voltage drive module 120.

[0029] In this embodiment, the control module 130 uses an embedded microcontroller (such as the STM32F4 series), receives the real-time driving speed collected by the vehicle speed sensor 110 through the CAN bus, converts the real-time driving speed into a target voltage amplitude according to a preset algorithm, and sends the target voltage amplitude to the voltage drive module 120 through the communication interface.

[0030] The control module 130 can convert real-time driving speed into a target voltage amplitude using various methods. For example, the target voltage amplitude can be calculated using a preset mathematical formula, i.e., establishing a functional relationship U=f(v) between real-time driving speed v and voltage amplitude U, and substituting the real-time driving speed into the formula to calculate the corresponding target voltage amplitude. Alternatively, the control module 130 can pre-store a mapping relationship between real-time driving speed and voltage amplitude, and can query this mapping relationship based on the real-time driving speed to obtain the corresponding target voltage amplitude. Furthermore, the system continuously optimizes and updates the mapping relationship during use, making the control more precise.

[0031] In this embodiment, the mapping relationship between real-time driving speed and voltage amplitude is as follows: (1) When the real-time driving speed is greater than the first preset threshold, the corresponding voltage amplitude is less than the first voltage threshold. The first preset threshold is 80-120 km / h, and the first voltage threshold is less than 5V. For example, when the real-time driving speed is 90 km / h, the first voltage threshold is 0V.

[0032] (2) When the real-time driving speed is less than the second preset threshold, the corresponding voltage amplitude is greater than the second voltage threshold. The second preset threshold is 20-40 km / h, and the second voltage threshold is greater than 40V. For example, when the real-time driving speed is 30 km / h, the second voltage threshold is 60V.

[0033] (3) When the real-time driving speed is greater than the first preset threshold and less than the second preset threshold, the voltage amplitude is negatively correlated with the real-time driving speed. That is, the higher the real-time driving speed, the lower the voltage amplitude; the lower the real-time driving speed, the higher the voltage amplitude. For example, the real-time driving speed is 60 km / h and the second voltage threshold is 40V. The negative correlation can be a linear relationship, a piecewise linear relationship, or a nonlinear relationship, which is not limited here.

[0034] Based on the above mapping relationship, the control module 130 is further configured to: when the real-time driving speed is greater than the first preset threshold, determine a target voltage amplitude that is less than the first voltage threshold so that the wetting state of the surface of the transparent electrowetting glass panel 140 is hydrophobic; when the real-time driving speed is less than the second preset threshold, determine a target voltage amplitude that is greater than the second voltage threshold so that the wetting state of the surface of the transparent electrowetting glass panel 140 is hydrophilic; when the real-time driving speed is less than the first preset threshold and greater than the second preset threshold, determine a target voltage amplitude based on the negative correlation between the voltage amplitude and the real-time driving speed.

[0035] The voltage driving module 120 is electrically connected to the transparent conductive electrode layer in the transparent electrowetting glass panel 140, and is used to apply a voltage corresponding to the target voltage amplitude to the transparent conductive electrode layer.

[0036] The voltage driving module 120 can be a programmable high-voltage power supply with an output range of 0-100V, a resolution of 0.1V, and a response time of less than 50ms. The voltage driving module 120 receives the target voltage amplitude sent by the control module 130, generates and outputs a voltage corresponding to the voltage amplitude to the transparent conductive electrode layer.

[0037] The transparent electrowetting glass panel 140 includes a glass substrate, a transparent conductive electrode layer, a dielectric layer and a hydrophobic functional layer stacked sequentially. The transparent conductive electrode layer and the dielectric layer form an insulating capacitor structure. When a voltage is applied to the transparent conductive electrode layer, the contact angle between the hydrophobic functional layer and the water droplet is adjusted by the electrowetting effect of the insulating capacitor structure, thereby adjusting the wetting state of the surface of the transparent electrowetting glass panel 140.

[0038] The glass substrate is made of ordinary automotive windshield glass, with a thickness of 3-5mm. It has sufficient mechanical strength and good light transmittance to meet the safety requirements and visibility needs during vehicle operation.

[0039] The transparent conductive electrode layer is made of indium tin oxide (ITO) or aluminum-doped zinc oxide (AZO) thin film with a thickness of 100-300 nm and a sheet resistance ≤50 Ω / sq. In this embodiment, the transparent conductive electrode layer adopts a full-surface electrode structure, which realizes unified control of the wetting state of the entire glass surface, simplifying the control logic and reducing manufacturing costs.

[0040] In another implementation, the transparent conductive electrode layer may also include an electrode array formed by multiple independently controllable electrode units. In this implementation, the control module 130 is further configured to determine a uniform target voltage amplitude based on the real-time driving speed, and apply the uniform target voltage amplitude to each electrode unit via the voltage drive module 120, thereby achieving uniform control of the wetting state of the entire glass surface. This embodiment uses a uniform voltage application method to simplify control and reduce costs, but this solution does not exclude the possibility of implementing zoned differentiated control.

[0041] It should be noted that since each electrode unit is independently controllable, in certain application scenarios, different applied voltages can be generated according to the distribution of stains, lighting conditions, or field of view requirements in different areas, and voltages of different amplitudes can be applied to different electrode units to achieve differentiated control of glass surface partitions.

[0042] The dielectric layer uses a high dielectric constant material (such as hafnium dioxide HfO2), with a thickness of 200 nm and a transmittance greater than 90%. High dielectric constant materials can achieve a large capacitance value at a relatively thin thickness, thereby reducing the operating voltage required for electrowetting effect and improving response speed.

[0043] The hydrophobic functional layer is a self-assembled monolayer of fluorosilane with an initial contact angle of 120°. This means that the glass surface exhibits superhydrophobic properties when no voltage is applied. The hydrophobic functional layer is extremely thin and does not affect the light transmittance of the glass. It also has good wear resistance and chemical stability.

[0044] The transparent conductive electrode layer and the dielectric layer form an insulating capacitor structure. When the voltage driving module 120 applies a voltage to the transparent conductive electrode layer, this insulating capacitor structure stores electrostatic energy, reducing the solid-liquid interfacial tension between the hydrophobic functional layer and the water droplet, thereby reducing the contact angle between the hydrophobic functional layer and the water droplet. Specifically, the higher the voltage applied to the transparent conductive electrode layer, the smaller the contact angle between the hydrophobic functional layer and the water droplet, and the more hydrophilic the wetting state of the transparent electrowetting glass panel 140 surface tends to be; when the voltage applied to the transparent conductive electrode layer is zero or low, the contact angle is larger, and the wetting state of the transparent electrowetting glass panel 140 surface remains hydrophobic. This process is reversible; after the voltage applied to the transparent conductive electrode layer is removed, the solid-liquid interfacial tension recovers, and the transparent electrowetting glass panel 140 surface returns to a hydrophobic state. By continuously adjusting the amplitude of the applied voltage, the contact angle can be continuously adjusted from 30° to 120°, thereby precisely matching the wetting state of the transparent electrowetting glass panel 140 surface with the driving speed.

[0045] In this embodiment, when the target voltage amplitude is less than the first voltage threshold, the surface of the transparent electrowetting glass panel 140 remains hydrophobic (contact angle ≥ 110°) to utilize high-speed airflow to assist in drainage or blowing away stains. When the target voltage amplitude is greater than the second voltage threshold, the surface of the transparent electrowetting glass panel 140 switches to a hydrophilic state (contact angle ≤ 90°) to enhance the spreading ability of washing liquid or rainwater.

[0046] To achieve the automatic cleaning function of the transparent electrowetting glass panel 140, the system is also equipped with a cleaning liquid spraying module. Specifically, the system also includes a cleaning liquid spraying module connected to the control module 130; the control module 130 is also used to send a spraying command to the cleaning liquid spraying module when it determines that the surface of the transparent electrowetting glass panel 140 needs to be cleaned; the cleaning liquid spraying module is used to spray cleaning liquid onto the surface of the transparent electrowetting glass panel 140 in response to the spraying command.

[0047] When determining whether the surface of the transparent electrowetting glass panel 140 needs to be cleaned, one or more of the following methods can be used: (1) Manual triggering method Users can actively trigger the cleaning process via in-vehicle buttons, touchscreens, or voice commands. For example, if a user notices bird droppings on the transparent electrowetting glass panel 140, pressing the cleaning button will trigger the system to determine that cleaning is needed.

[0048] (2) Automatic triggering method An optical sensor (such as a camera or photoelectric sensor) is installed inside the transparent electrowetting glass panel 140 to detect the distribution and degree of dirt on the panel surface in real time. When the detected dirt area exceeds a preset threshold or the light transmittance is lower than a preset threshold, the system automatically determines that cleaning is required.

[0049] When it is determined that the surface of the transparent electrowetting glass panel 140 needs to be cleaned, the control module 130 sends a spraying command to the cleaning liquid spraying module, which responds to the command by spraying 10ml of protease cleaner onto the bird droppings area.

[0050] To ensure that the cleaning fluid can spread sufficiently on the transparent electrowetting glass panel 140 without being dispersed by airflow, the system adopts a control strategy of first adjusting the wetting state and then spraying the cleaning fluid. Specifically, the control module 130 is also used to: determine the target voltage amplitude based on a preset mapping relationship and real-time driving speed when it is determined that the surface of the transparent electrowetting glass panel 140 needs to be cleaned, and send the target voltage amplitude to the voltage drive module 120; after determining that the voltage drive module 120 applies a voltage corresponding to the target voltage amplitude to the transparent conductive electrode layer to make the surface of the transparent electrowetting glass panel 140 in a stable hydrophilic state, send a spraying command to the cleaning fluid spraying module.

[0051] During the cleaning process, the control module 130 first applies a voltage corresponding to the target voltage amplitude to the transparent conductive electrode layer through the voltage drive module 120. After the wetting state of the transparent electrowetting glass panel 140 stabilizes (about 100ms), the washing liquid is sprayed through the washing liquid spraying module to ensure that the washing liquid spreads immediately and is not blown away by the airflow.

[0052] After the detergent spray is completed, the softened stains and detergent need to be scraped off by the wipers to complete the entire cleaning process. Specifically, the system also includes a wiper module connected to the control module 130; the control module 130 is also used to send a wiping command to the wiper module after sending a spray command to the detergent spray module; the wiper module is also used to perform a wiping operation on the surface of the transparent electrowetting glass panel 140 in response to the wiping command.

[0053] Optionally, the control module 130 can send a spray command to the washer fluid spray module, wait for a predetermined time, and then send a wiping command to the wiper module. This predetermined time allows the washer fluid to fully soak the stains and soften the deposits, thereby improving the wiping and cleaning effect. For example, after spraying the washer fluid, soaking for 30 seconds before activating the wipers can easily remove bird droppings. The specific value of the predetermined time can be calibrated or adaptively adjusted according to the type of stain, the characteristics of the washer fluid, and environmental conditions. For example, it can be set to 5-10 seconds for ordinary dust and 20-30 seconds for bird droppings or insect residue.

[0054] As another implementation, the control module 130 can also send a wiping command to the wiper module immediately after sending a spray command to the detergent spray module, which is suitable for scenarios with light stains or those requiring quick cleaning.

[0055] The uniform liquid film formed by the detergent in a hydrophilic state has a lubricating effect, which can reduce the friction when the wipers are wiping, reduce the wear of the wiper blades, and extend the wiper life by more than 2 times.

[0056] The aforementioned mapping relationship is not fixed but is obtained through pre-calibration, which requires comprehensive consideration of multiple factors affecting the cleaning effect. Specifically, the control module 130 is also used to: measure the influence of airflow on the spread of the washing liquid at different driving speeds; measure the adhesion efficiency of the washing liquid under different wetting conditions; measure the friction and wear data during wiper wiping; and determine the mapping relationship between different driving speeds and different voltage amplitudes based on the influence data, adhesion efficiency data, and friction and wear data.

[0057] The calibration objectives and procedures for combining wind tunnel experiments with field testing are explained below.

[0058] The target objective is to maximize the adhesion efficiency of the washing liquid to the glass surface at different vehicle speeds, without wasting the droplets due to airflow blowing or excessive spreading.

[0059] Calibration process: 1. Place the vehicle in a wind tunnel and set different wind speeds (corresponding to different driving speeds).

[0060] 2. The adhesion rate of the detergent spray was measured at different voltage amplitudes (0, 20, 40, 60, 80V) (the number of droplets hitting the glass was counted by high-speed camera). The specific data are shown in Table 1.

[0061] 3. Draw a three-dimensional surface of adhesion rate-driving speed-voltage amplitude, and select the voltage amplitude with the highest adhesion rate at each driving speed as the mapped voltage amplitude.

[0062] 4. Fit the discrete points to obtain the continuous mapping function U=f(v).

[0063] Table 1

[0064] The above data shows that this embodiment can increase the detergent adhesion rate from 30%-50% in the traditional solution to 85%-95%, reduce detergent usage by 50%-70%, and achieve significant water-saving effect.

[0065] During actual driving, the driving speed may fluctuate slightly. If the voltage amplitude changes frequently with the driving speed, the wetting state of the transparent electrowetting glass panel 140 may repeatedly switch around the threshold, affecting system stability and user experience. To avoid the above problems, this embodiment introduces a hysteresis interval and uses an asymmetric threshold for voltage switching control. Specifically: When the driving speed increases, the voltage switching threshold is set to: high-speed threshold v high up =95 km / h, low speed threshold v low up =45 km / h; When the driving speed decreases, the voltage switching threshold is set to: high-speed threshold v high down =85 km / h, low speed threshold v low down =35 km / h.

[0066] In other words, as the driving speed increases, the switching threshold rises to 95 km / h (higher than the original threshold of 90 km / h), and as the driving speed decreases, the switching threshold decreases to 85 km / h (lower than the original threshold of 90 km / h). This creates a hysteresis range between 85 km / h and 95 km / h. When the driving speed fluctuates within this range, the system state remains unchanged, and no switching occurs. Similarly, a similar hysteresis range is set between the low-speed and medium-speed regions: switching only occurs when the driving speed exceeds 45 km / h and when the driving speed decreases, switching only occurs when the driving speed falls below 35 km / h, forming a hysteresis range of 35 km / h to 45 km / h. Through this asymmetric threshold design, when the driving speed fluctuates near the threshold, the system will not immediately switch the voltage amplitude, thus preventing repeated switching near the threshold and improving the system's stability and control smoothness.

[0067] This application fully utilizes airflow energy during high-speed driving and can maintain a hydrophobic state without applying voltage (zero energy consumption); it only consumes a small amount of electrical energy to drive the electrowetting effect during low-speed driving or washing, resulting in low overall energy consumption and conforming to the trend of energy conservation and environmental protection.

[0068] In summary, the electrowetting surface control system provided in this application embodiment achieves dynamic matching between the wettability of the transparent electrowetting glass panel surface and the driving speed (i.e., airflow intensity): at high speeds, it maintains a hydrophobic state to assist drainage, and raindrops form spherical droplets that quickly roll off under the action of airflow, avoiding water film from affecting the driver's vision; at low speeds, it switches to a hydrophilic state to assist cleaning, shorten cleaning time, and reduce visual interference; at medium speeds, it is in a moderately hydrophilic state to achieve balance, so that the self-cleaning performance reaches its optimal level across the entire vehicle speed range.

[0069] In a hydrophobic state, raindrops are easily blown away by airflow, significantly reducing the frequency of wiper usage. During cleaning, in a hydrophilic state, the detergent can quickly spread into a uniform liquid film on the glass panel surface, greatly improving adhesion efficiency. Furthermore, the uniform liquid film formed by the detergent has a lubricating effect, which can reduce friction during wiper wiping, reduce wear on wiper blades, and extend wiper life.

[0070] The transparent conductive electrode layer comprises an electrode array formed by multiple independent and controllable electrode units. A uniform target voltage amplitude can be applied to each electrode unit, thereby achieving uniform control of the wetting state of the entire glass surface. This eliminates the need for complex partition control circuits and multiple independent drive channels, making it easy to integrate into existing automotive glass manufacturing processes with limited cost increases.

[0071] The working process of the electrowetting surface control system described in this embodiment will be explained in detail below in conjunction with specific driving scenarios.

[0072] (1) High-speed driving scenario When the vehicle is traveling at 120 km / h on the highway, the control module 130 obtains the driving speed signal v=120 km / h via the CAN bus, determines that the driving speed is greater than the first preset threshold of 90 km / h, and determines that the target voltage amplitude is 0V. The control module 130 sends 0V to the voltage drive module 120, which applies a voltage to the transparent conductive electrode layer to keep the transparent electrowetting glass panel 140 in a superhydrophobic state (contact angle 120°). At this time, raindrops falling on the transparent electrowetting glass panel 140 form spherical droplets, which quickly roll off under the action of high-speed airflow, resulting in good self-cleaning effect. Under high-speed conditions, the system maintains a hydrophobic state and makes full use of airflow to assist drainage, without consuming electrical energy or detergent.

[0073] (2) Medium-speed driving scenario When the vehicle is traveling at 60 km / h on an urban expressway, the control module 130 obtains the driving speed v = 60 km / h and determines that the driving speed is between the second preset threshold of 40 km / h and the first preset threshold of 90 km / h. Based on the negative correlation, it calculates or looks up the target voltage amplitude of 40V. The control module 130 sends 40V to the voltage drive module 120, which applies a 40V voltage to the transparent conductive electrode layer. The transparent electrowetting glass panel 140 becomes moderately hydrophilic (contact angle approximately 65°). At this time, rainwater spreads into a thin layer on the transparent electrowetting glass panel 140 and flows evenly under the action of airflow, making it less likely to form a water film that obstructs vision. Under medium-speed conditions, the system, through a moderate hydrophilic state, allows rainwater to spread evenly and flow away with the airflow, reducing reliance on windshield wipers.

[0074] (3) Scenarios where low-speed driving is required and cleaning is needed When a vehicle is traveling at 30 km / h on urban roads and the user needs to clean bird droppings, the control module 130 obtains the driving speed v = 30 km / h and determines that the speed is less than the second preset threshold of 40 km / h, thus setting the target voltage amplitude to 60V. The control module 130 sends 60V to the voltage drive module 120, which applies 60V to the transparent conductive electrode layer, causing the transparent electrowetting glass panel 140 to switch to a superhydrophilic state (contact angle approximately 30°). Subsequently, the control module 130 controls the washing liquid spraying module to spray washing liquid onto the transparent electrowetting glass panel 140. The washing liquid quickly spreads and forms a film on the hydrophilic surface, completely covering the bird droppings, which are then easily removed by the wipers after soaking. Under low-speed conditions, the system switches to a hydrophilic state, allowing the washing liquid to spread fully, compensating for the shortcomings of airflow assistance and achieving a highly efficient and water-saving cleaning effect.

[0075] (4) Scenarios with continuous changes in vehicle speed As the vehicle gradually decelerates from high speed, the control module 130 continuously monitors changes in speed and dynamically adjusts the target voltage amplitude based on the real-time speed. For example, when the speed decreases from 120 km / h to 60 km / h, the voltage amplitude gradually increases from 0V to 40V; when the speed continues to decrease to 30 km / h, the voltage amplitude further increases to 60V. Conversely, when the vehicle accelerates, the voltage amplitude decreases as the speed increases. The system enables continuous dynamic adjustment of the wetting state of the transparent electrowetting glass panel 140 surface with speed, thereby maintaining optimal self-cleaning performance across the entire vehicle speed range.

[0076] like Figure 2 The diagram illustrates a flowchart of an electrowetting surface control method according to an embodiment of this application, which can be applied to vehicles. This electrowetting surface control method may include: Step 201: Obtain the vehicle's real-time speed.

[0077] The vehicle speed sensor is installed on the output shaft of the vehicle's transmission or at the wheel hub. It collects real-time driving speed at a sampling frequency of 10Hz and sends the real-time driving speed to the control module via the CAN bus.

[0078] Step 202: Determine the target voltage amplitude based on the real-time driving speed.

[0079] The control module receives real-time driving speed data collected by the vehicle speed sensor via the CAN bus, converts the real-time driving speed into a target voltage amplitude according to a preset algorithm, and sends the target voltage amplitude to the voltage drive module through the communication interface.

[0080] The control module can convert real-time driving speed into a target voltage amplitude using various methods. For example, the target voltage amplitude can be calculated using a preset mathematical formula, establishing a functional relationship U=f(v) between the real-time driving speed v and the voltage amplitude U. Substituting the real-time driving speed into the formula yields the corresponding target voltage amplitude. Alternatively, the control module can pre-store a mapping relationship between real-time driving speed and voltage amplitude, allowing it to query this mapping relationship based on the real-time driving speed to obtain the corresponding target voltage amplitude. Furthermore, the system continuously optimizes and updates the mapping relationship during use, resulting in more precise control.

[0081] When converting real-time driving speed into a target voltage amplitude, if the real-time driving speed is greater than a first preset threshold, a target voltage amplitude less than the first voltage threshold is determined so that the wetting state of the transparent electrowetting glass panel surface is hydrophobic; if the real-time driving speed is less than a second preset threshold, a target voltage amplitude greater than the second voltage threshold is determined so that the wetting state of the transparent electrowetting glass panel surface is hydrophilic; if the real-time driving speed is less than the first preset threshold and greater than the second preset threshold, a target voltage amplitude is determined based on the negative correlation between voltage amplitude and real-time driving speed.

[0082] Step 203: Apply a voltage corresponding to the target voltage amplitude to the transparent conductive electrode layer in the transparent electrowetting glass panel to adjust the wetting state of the transparent electrowetting glass panel surface.

[0083] In this embodiment, the transparent conductive electrode layer includes an electrode array formed by multiple independently controllable electrode units. The control module can determine a uniform target voltage amplitude based on the real-time driving speed, and apply the uniform target voltage amplitude to each electrode unit through the voltage drive module, thereby achieving uniform control of the wetting state of the entire glass surface. This embodiment adopts a uniform voltage application method to simplify control and reduce costs, but this solution does not exclude the possibility of implementing differentiated control in different zones.

[0084] To enable automatic cleaning of the transparent electrowetting glass panel, the system is also equipped with a cleaning fluid spraying module. Specifically, the system also includes a cleaning fluid spraying module connected to the control module; when the control module determines that the surface of the transparent electrowetting glass panel needs to be cleaned, it sends a spraying command to the cleaning fluid spraying module; the cleaning fluid spraying module responds to the spraying command and sprays cleaning fluid onto the surface of the transparent electrowetting glass panel.

[0085] When it is determined that the surface of the transparent electrowetting glass panel needs to be cleaned, the control module sends a spray command to the cleaning liquid spraying module. In response to the command, the cleaning liquid spraying module sprays 10ml of protease cleaner onto the bird droppings area.

[0086] To ensure the cleaning solution spreads fully on the transparent electrowetting glass panel without being dispersed by airflow, the system employs a control strategy of first adjusting the wetting state before spraying the cleaning solution. Specifically, when the control module determines that the surface of the transparent electrowetting glass panel needs to be cleaned, it determines the target voltage amplitude based on a preset mapping relationship and the real-time driving speed, and sends the target voltage amplitude to the voltage drive module. After determining that the voltage drive module applies a voltage corresponding to the target voltage amplitude to the transparent conductive electrode layer to bring the surface of the transparent electrowetting glass panel into a stable hydrophilic state, it sends a spraying command to the cleaning solution spraying module.

[0087] During the cleaning process, the control module first applies a voltage corresponding to the target voltage amplitude to the transparent conductive electrode layer through the voltage drive module. After the wetting state of the transparent electrowetting glass panel stabilizes (about 100ms), the washing liquid is sprayed through the washing liquid spray module to ensure that the washing liquid spreads immediately and is not blown away by the airflow.

[0088] After the detergent spray is completed, the softened stains and detergent need to be scraped off by the wipers to complete the cleaning process. Specifically, the system also includes a wiper module connected to the control module; after sending a spray command to the detergent spray module, the control module sends a wiping command to the wiper module; the wiper module responds to the wiping command and performs a wiping operation on the transparent electrowetted glass panel surface.

[0089] Optionally, the control module can send a spray command to the washer fluid spray module and then wait a predetermined time before sending a wiping command to the wiper module. This predetermined time allows the washer fluid to fully soak the stains and soften the adhering substances, thereby improving the wiping and cleaning effect. For example, after spraying the washer fluid, soaking for 30 seconds before starting the wipers can easily remove bird droppings. The specific value of the predetermined time can be calibrated or adaptively adjusted according to the type of stain, the characteristics of the washer fluid, and environmental conditions. For example, it can be set to 5-10 seconds for ordinary dust and 20-30 seconds for bird droppings or insect residue. As another implementation, the control module can also send a wiping command to the wiper module immediately after sending the spray command to the washer fluid spray module, which is suitable for scenarios with light stains or requiring quick cleaning. The uniform liquid film formed by the washer fluid in its hydrophilic state has a lubricating effect, which can reduce the friction during wiper wiping, reduce the wear of the wiper blades, and extend the wiper life by more than 2 times.

[0090] The aforementioned mapping relationship is not fixed but is obtained through pre-calibration. Calibration requires comprehensive consideration of multiple factors affecting the cleaning effect. Specifically, the control module measures the impact of airflow on the spread of the wash liquid at different driving speeds; measures the adhesion efficiency of the wash liquid under different wetting conditions; and measures the friction and wear data during wiper operation. Based on the impact data, adhesion efficiency data, and friction and wear data, the mapping relationship between different driving speeds and different voltage amplitudes is determined. The wind tunnel and field test data during calibration are detailed in Table 1 and will not be repeated here.

[0091] This application fully utilizes airflow energy during high-speed driving and can maintain a hydrophobic state without applying voltage (zero energy consumption); it only consumes a small amount of electrical energy to drive the electrowetting effect during low-speed driving or washing, resulting in low overall energy consumption and conforming to the trend of energy conservation and environmental protection.

[0092] In summary, the electrowetting surface control method provided in this application embodiment achieves dynamic matching between the wettability of the transparent electrowetting glass panel surface and the driving speed (i.e., airflow intensity): at high speeds, it maintains a hydrophobic state to assist drainage, and raindrops form spherical droplets that quickly roll off under the action of airflow, avoiding water film from affecting the driver's vision; at low speeds, it switches to a hydrophilic state to assist cleaning, shorten cleaning time, and reduce visual interference; at medium speeds, it is in a moderately hydrophilic state to achieve balance, so that the self-cleaning performance reaches its optimal level across the entire vehicle speed range.

[0093] In a hydrophobic state, raindrops are easily blown away by airflow, significantly reducing the frequency of wiper usage. During cleaning, in a hydrophilic state, the detergent can quickly spread into a uniform liquid film on the glass panel surface, greatly improving adhesion efficiency. Furthermore, the uniform liquid film formed by the detergent has a lubricating effect, which can reduce friction during wiper wiping, reduce wear on wiper blades, and extend wiper life.

[0094] The transparent conductive electrode layer comprises an electrode array formed by multiple independent and controllable electrode units. A uniform target voltage amplitude can be applied to each electrode unit, thereby achieving uniform control of the wetting state of the entire glass surface. This eliminates the need for complex partition control circuits and multiple independent drive channels, making it easy to integrate into existing automotive glass manufacturing processes with limited cost increases.

[0095] One embodiment of this application provides a computer-readable storage medium storing at least one instruction, which is loaded and executed by a processor to implement the electrowetting surface control method as described above.

[0096] It should be understood that the various forms of processes shown above can be used to rearrange, add, or delete steps. For example, the steps described in this disclosure can be executed in parallel, sequentially, or in different orders, as long as the desired result of the technical solution disclosed in this application can be achieved, and this is not limited herein.

[0097] The specific embodiments described above do not constitute a limitation on the scope of protection of this application. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this application should be included within the scope of protection of this application.

Claims

1. A surface electrowetting control system, characterized in that, The system includes: a vehicle speed sensor, a voltage drive module, a control module, and a transparent electrowetting glass panel; The vehicle speed sensor is used to obtain the real-time driving speed of the vehicle; The control module is connected to the vehicle speed sensor and the voltage drive module respectively, and is used to determine the target voltage amplitude according to the real-time driving speed and send the target voltage amplitude to the voltage drive module; The voltage driving module is electrically connected to the transparent conductive electrode layer in the transparent electrowetting glass panel, and is used to apply a voltage corresponding to the target voltage amplitude to the transparent conductive electrode layer; The transparent electrowetting glass panel includes a glass substrate, a transparent conductive electrode layer, a dielectric layer, and a hydrophobic functional layer stacked sequentially. The transparent conductive electrode layer and the dielectric layer form an insulating capacitor structure. When a voltage is applied to the transparent conductive electrode layer, the electrowetting effect of the insulating capacitor structure adjusts the contact angle between the hydrophobic functional layer and the water droplet, thereby adjusting the wetting state of the surface of the transparent electrowetting glass panel.

2. The electrowetting surface control system according to claim 1, characterized in that, The control module is also used for: When the real-time driving speed is greater than the first preset threshold, a target voltage amplitude less than the first voltage threshold is determined so that the wetting state of the transparent electrowetting glass panel surface is a hydrophobic state. When the real-time driving speed is less than the second preset threshold, a target voltage amplitude greater than the second voltage threshold is determined so that the wetting state of the transparent electrowetting glass panel surface is a hydrophilic state. When the real-time driving speed is less than the first preset threshold and greater than the second preset threshold, the target voltage amplitude is determined based on the negative correlation between the voltage amplitude and the real-time driving speed.

3. The electrowetting surface control system according to claim 1, characterized in that, The transparent conductive electrode layer includes an electrode array formed by multiple independently controllable electrode units; The control module is also used to determine a uniform target voltage amplitude based on the real-time driving speed, and apply the uniform target voltage amplitude to each electrode unit through the voltage driving module.

4. The electrowetting surface control system according to claim 1, characterized in that, The system also includes a detergent spraying module connected to the control module; The control module is also used to send a spraying command to the cleaning liquid spraying module when it is determined that the surface of the transparent electrowetting glass panel needs to be cleaned. The detergent spraying module is used to spray detergent onto the surface of the transparent electrowetting glass panel in response to the spraying command.

5. The electrowetting surface control system according to claim 4, characterized in that, The control module is also used for: When it is determined that the surface of the transparent electrowetting glass panel needs to be cleaned, the target voltage amplitude is determined according to the preset mapping relationship and the real-time driving speed, and the target voltage amplitude is sent to the voltage driving module. After determining that the voltage driving module applies a voltage corresponding to the target voltage amplitude to the transparent conductive electrode layer so that the surface of the transparent electrowetting glass panel is in a stable hydrophilic state, a spraying command is sent to the washing liquid spraying module.

6. The electrowetting surface control system according to claim 4, characterized in that, The system also includes a wiper module connected to the control module; The control module is also used to send a wiping command to the wiper module after sending a spray command to the wash liquid spray module. The wiper module is also configured to perform a wiping operation on the transparent electrowetting glass panel surface in response to the wiping command.

7. The electrowetting surface control system according to claim 5, characterized in that, The control module is also used for: Data on the effect of airflow on the spreading of detergent at different travel speeds were measured. Measure the adhesion efficiency data of the detergent under different wetting conditions; Measure the friction and wear data during windshield wiper operation; Based on the influence data, the adhesion efficiency data, and the friction and wear data, the mapping relationship between different driving speeds and different voltage amplitudes is determined.

8. A method for controlling the electrowetting surface, characterized in that, For use in the electrowetting surface control system as described in any one of claims 1 to 7, the method comprises: Obtain the vehicle's real-time speed; The target voltage amplitude is determined based on the real-time driving speed; A voltage corresponding to the target voltage amplitude is applied to the transparent conductive electrode layer in the transparent electrowetting glass panel to adjust the wetting state of the transparent electrowetting glass panel surface.

9. A computer-readable storage medium, characterized in that, The storage medium stores at least one instruction, which is loaded and executed by a processor to implement the electrowetting surface control method as described in claim 8.

10. A vehicle, characterized in that, The vehicle includes an electrowetting surface control system as described in any one of claims 1 to 7.

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