Ultrasonic cleaning method and device, vehicle-mounted camera and vehicle

Abstract

The invention provides an ultrasonic cleaning method which comprises the steps that an ultrasonic transducer is connected with a cleaned object, and the ultrasonic transducer is suitable for resonating with the cleaned object; acquiring the characteristics of the ultrasonic transducer when the ultrasonic transducer and the cleaned object resonate; and according to the characteristics, if the cleaned object is dirty, cleaning the cleaned object. The dirt is judged according to the characteristics of the ultrasonic transducer when the ultrasonic transducer resonates with the cleaned object, an image of a camera does not need to be analyzed, the method does not depend on an image algorithm and a domain controller decision, and the response speed is high. The invention further provides an ultrasonic cleaning device, a vehicle-mounted camera and a vehicle.

Description

Technical Field

[0001] The present application relates to the field of cleaning, and in particular to an ultrasonic cleaning method, device, vehicle-mounted camera, and vehicle. Background Art

[0002] With the development of intelligent driving technology, vehicle-mounted cameras have become very important sensors on the vehicle body. If the camera is blocked by dirt, it will seriously affect the relevant functions of the vehicle and thus affect driving safety.

[0003] In the existing ultrasonic cleaning method, the camera image is analyzed and image algorithms are relied upon to determine the dirt on the camera. The initial training cost is high, and the later stage relies on the vehicle's intelligent driving domain controller. The system is complex and occupies the computing power of the vehicle's intelligent driving domain controller. Summary of the Invention

[0004] Embodiments of the present invention provide an ultrasonic cleaning method, device, and vehicle-mounted camera to at least partially solve the above-mentioned problems.

[0005] In order to achieve the above object, according to a first aspect of the present invention, there is provided an ultrasonic cleaning method, comprising: connecting an ultrasonic transducer to the object to be cleaned, wherein the ultrasonic transducer is suitable for resonating with the object to be cleaned; Acquiring characteristics of the ultrasonic transducer when the ultrasonic transducer resonates with the object to be cleaned; According to the feature, if the object to be cleaned is dirty, the object to be cleaned is cleaned.

[0006] Through the above method, the characteristics of the ultrasonic transducer when the ultrasonic transducer resonates with the object to be cleaned are used to judge dirtiness. There is no need to analyze the image of the camera, and it does not rely on the image algorithm and the domain controller decision. It has a fast response speed and can work independently, freeing up the computing power of the domain controller.

[0007] Optionally, the characteristic of the ultrasonic transducer includes at least one of a resonant frequency and an impedance.

[0008] Optionally, according to the feature, if the object to be cleaned is dirty, cleaning the object to be cleaned includes: The resonant frequency is obtained and compared with a preset resonant frequency. If the difference between the resonant frequency and the preset resonant frequency is greater than a first threshold, the object to be cleaned is dirty; the preset resonant frequency is the resonant frequency when the ultrasonic transducer resonates with the object to be cleaned when the object to be cleaned is not dirty.

[0009] Optionally, according to the feature, if the object to be cleaned is dirty, cleaning the object to be cleaned includes: The impedance is obtained and compared with a preset impedance. If the difference between the impedance and the preset impedance is greater than a second threshold, the object to be cleaned is dirty; the preset impedance is the impedance of the ultrasonic transducer when the ultrasonic transducer resonates with the object to be cleaned when the object to be cleaned is not dirty.

[0010] Optionally, according to the feature, if the object to be cleaned is dirty, cleaning the object to be cleaned includes: If the object to be cleaned is dirty, determining the type of the dirt according to the characteristics; According to the type of dirt, the object to be cleaned is cleaned in a corresponding manner.

[0011] Optionally, the cleaning of the object to be cleaned in a corresponding manner according to the type of dirt includes: According to the type of dirt, the ultrasonic transducer generates a corresponding vibration frequency to clean the object to be cleaned.

[0012] Optionally, according to the feature, if the object to be cleaned is dirty, cleaning the object to be cleaned includes: If the object to be cleaned is dirty, several preset cleaning modes are used to clean the object to be cleaned in sequence; the several preset cleaning modes are the resonant frequencies corresponding to several common dirts attached to the object to be cleaned.

[0013] Optionally, the several common dirt include but are not limited to one or more of water droplets, dust, mud spots and oil stains.

[0014] According to a second aspect of the present invention, there is provided an ultrasonic cleaning device comprising: Controller; an ultrasonic transducer connected to the object to be cleaned, wherein the ultrasonic transducer is adapted to resonate with the object to be cleaned; a detection module, configured to obtain characteristics of the ultrasonic transducer when the ultrasonic transducer resonates with the object to be cleaned; The controller determines whether the object to be cleaned is dirty according to the feature. If the object to be cleaned is dirty, the controller controls the ultrasonic transducer to resonate with the object to be cleaned to clean the object.

[0015] Optionally, a driving circuit is further included for inverting direct current into alternating current, the frequency of the alternating current being the resonant frequency of the ultrasonic transducer, and the controller is connected to the ultrasonic transducer via the driving circuit.

[0016] Optionally, the drive circuit includes a gate driver and a half-bridge inverter circuit, the controller outputs a PWM signal to the gate driver, and the gate driver controls the switching of the power tube in the half-bridge inverter circuit according to the PWM signal, so that the half-bridge inverter converts direct current into alternating current of corresponding frequency.

[0017] Optionally, the PWM signal includes a PWMA signal and a PWMB signal, the PWMA signal and the PWMB signal are 180 degrees out of phase with each other, and have the same frequency and duty cycle.

[0018] Optionally, the driving circuit further includes a transformer, which is connected to the half-bridge inverter and converts the voltage of the alternating current output by the half-bridge inverter into a voltage suitable for the ultrasonic transducer.

[0019] Optionally, the PWM signal output by the controller is transmitted to the gate driver through an IO isolator, and the IO isolator is a high-speed optocoupler.

[0020] Optionally, the driving circuit is connected to the ultrasonic transducer via an impedance matching circuit, and the impedance matching circuit includes a first inductor connected in series with the ultrasonic transducer.

[0021] Optionally, the detection module includes a sampling resistor, a current sampling module and a voltage sampling module, the sampling resistor is connected in series with the ultrasonic transducer, the current sampling module samples the current of the sampling resistor, and the voltage sampling module samples the voltage of the ultrasonic transducer.

[0022] Optionally, the controller calculates the impedance of the ultrasonic transducer according to the data collected by the current sampling module and the voltage sampling module.

[0023] Optionally, a memory is further included for storing the ultrasonic cleaning method proposed in the first aspect, so that the ultrasonic cleaning device is suitable for running the ultrasonic cleaning method to clean the object to be cleaned.

[0024] According to a third aspect of the present invention, there is provided a vehicle-mounted camera, comprising the ultrasonic cleaning device proposed in the second aspect, wherein the object to be cleaned is a lens of the vehicle-mounted camera.

[0025] According to a fourth aspect of the present invention, a vehicle is provided, comprising the ultrasonic cleaning device proposed in the second aspect or the vehicle-mounted camera proposed in the third aspect, wherein the controller is connected to a CAN bus of the vehicle.

[0026] Other features and advantages of the present application will be described in detail in the subsequent detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] To more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of the present application. Those skilled in the art can also derive other drawings based on these drawings without inventive effort.

[0028] In order to more completely understand the present application and its beneficial effects, the following description will be given in conjunction with the accompanying drawings, wherein the same drawing numbers represent the same parts in the following description.

[0029] Figure 1 1 is a flow chart of an ultrasonic cleaning method provided in one embodiment of the present invention; Figure 2 1 is a flow chart of an ultrasonic cleaning method provided in one embodiment of the present invention; Figure 3 is a schematic diagram of an ultrasonic cleaning device provided in one embodiment of the present invention; Figure 4 is a circuit diagram of an ultrasonic cleaning device provided in one embodiment of the present invention; Figure 5 1 is a schematic diagram of an impedance matching circuit for an ultrasonic transducer provided in one embodiment of the present invention; Figure 6 is a circuit diagram of a current sampling module provided in one embodiment of the present invention; Figure 7 4 is a circuit diagram of a voltage sampling module provided in one embodiment of the present invention. DETAILED DESCRIPTION

[0030] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the embodiments described are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present application.

[0031] According to the first aspect of the present invention, Figure 1 As shown, an ultrasonic cleaning method is provided, comprising: connecting an ultrasonic transducer to the object to be cleaned, wherein the ultrasonic transducer is suitable for resonating with the object to be cleaned; Acquiring characteristics of the ultrasonic transducer when the ultrasonic transducer resonates with the object to be cleaned; According to the feature, if the object to be cleaned is dirty, the object to be cleaned is cleaned.

[0032] In an embodiment of the present invention, the characteristic of the ultrasonic transducer includes at least one of a resonant frequency and an impedance.

[0033] Each material has its own resonant frequency. An ultrasonic transducer with a corresponding resonant frequency is selected based on the resonant frequency of the object being cleaned. In one embodiment of the present invention, the ultrasonic transducer is made of piezoelectric ceramic. An electrical signal is used to excite the ultrasonic transducer, generating mechanical vibrations that resonate with the object being cleaned. When dirt is present on the object being cleaned, its resonant frequency changes, with different types of dirt exhibiting different resonant frequencies.

[0034] In an implementation method of an embodiment of the present invention, if the object to be cleaned is contaminated based on the characteristics, cleaning the object to be cleaned includes: obtaining the resonant frequency, comparing it with a preset resonant frequency, and determining that the object to be cleaned is contaminated if the difference between the resonant frequency and the preset resonant frequency is greater than a first threshold value; the preset resonant frequency is the resonant frequency at which the ultrasonic transducer resonates with the object to be cleaned when the object to be cleaned is not contaminated. If the difference between the resonant frequency and the preset resonant frequency is less than or equal to the first threshold value, it is determined that the object to be cleaned is not contaminated, or the contamination is minor and does not affect normal use of the object to be cleaned.

[0035] In another implementation method of one embodiment of the present invention, if the object to be cleaned is contaminated based on the feature, cleaning the object includes: obtaining the impedance, comparing it with a preset impedance, and determining that the object to be cleaned is contaminated if the difference between the impedance and the preset impedance is greater than a second threshold value; the preset impedance is the impedance of the ultrasonic transducer when the ultrasonic transducer resonates with the object to be cleaned when the object to be cleaned is not contaminated. If the difference between the impedance and the preset impedance is less than or equal to the second threshold value, it is determined that the object to be cleaned is not contaminated, or the contamination is minor and does not affect normal use of the object to be cleaned.

[0036] In one embodiment of the present invention, if the object to be cleaned is contaminated based on the characteristics, cleaning the object includes: if the object to be cleaned is contaminated, determining the type of contamination based on the characteristics; and cleaning the object to be cleaned using a corresponding method based on the type of contamination. Different types of contamination correspond to different characteristics of the ultrasonic transducer when the ultrasonic transducer resonates with the object to be cleaned, and the type of contamination can be determined based on these characteristics. Furthermore, based on the type of contamination, the ultrasonic transducer generates a corresponding vibration frequency to clean the object to be cleaned.

[0037] In one embodiment of the present invention, it is also possible not to identify the type of dirt, but only to determine whether If dirt is present, the cleaning modes corresponding to common types of dirt are sequentially run, thus eliminating the step of identifying the type of dirt. According to the feature, if the object to be cleaned is dirty, cleaning the object to be cleaned includes: if the object to be cleaned is dirty, cleaning the object to be cleaned using several preset cleaning modes in sequence; the several preset cleaning modes are the resonant frequencies corresponding to several common types of dirt attached to the object to be cleaned. The several common dirt include, but are not limited to, one or more of water droplets, dust, mud spots, and oil stains. For example, when the object to be cleaned is stained with water droplets, the resonant frequency of the ultrasonic transducer is a first resonant frequency, corresponding to the first preset cleaning mode; when the object to be cleaned is stained with dust, the resonant frequency of the ultrasonic transducer is a second resonant frequency, corresponding to the second preset cleaning mode; when the object to be cleaned is stained with mud spots, the resonant frequency of the ultrasonic transducer is a third resonant frequency, corresponding to the third preset cleaning mode; and when the object to be cleaned is stained with oil, the resonant frequency of the ultrasonic transducer is a fourth resonant frequency, corresponding to the fourth preset cleaning mode. If the object to be cleaned is dirty, regardless of the type of dirt, the object to be cleaned is cleaned in the emcee's preset cleaning mode, the second preset cleaning mode, the third preset cleaning mode, and the fourth preset cleaning mode in sequence.

[0038] In one embodiment of the present invention, Figure 2 As shown, an ultrasonic cleaning method is provided, comprising the following steps: At fixed time intervals, the object being cleaned is checked for dirtiness; If the cleaned object is not dirty, continue to perform dirt detection on the cleaned object at fixed time intervals; If the object to be cleaned is dirty, several preset cleaning modes are run in sequence; If the object to be cleaned is still dirty, several preset cleaning modes are run again in sequence; If the object to be cleaned is not dirty, the object to be cleaned is detected for dirt at fixed time intervals.

[0039] According to a second aspect of the present invention, there is provided an ultrasonic cleaning device, such as Figure 3 As shown, it includes: a controller; an ultrasonic transducer connected to the object to be cleaned, and the ultrasonic transducer is suitable for resonating with the object to be cleaned; a detection module, used to obtain the characteristics of the ultrasonic transducer when the ultrasonic transducer resonates with the object to be cleaned; the controller determines whether the object to be cleaned is dirty based on the characteristics, and if the object to be cleaned is dirty, the controller controls the ultrasonic transducer to resonate with the object to be cleaned to clean the object to be cleaned.

[0040] In one embodiment of the present invention, a driving circuit is further included for inverting direct current into alternating current, the frequency of the alternating current is the resonant frequency of the ultrasonic transducer, and the controller is connected to the ultrasonic transducer via the driving circuit.

[0041] In one embodiment of the present invention, Figure 4 As shown, the drive circuit includes a gate driver and a half-bridge inverter circuit. The controller outputs a PWM signal to the gate driver. The gate driver controls the switching of the power transistors in the half-bridge inverter circuit according to the PWM signal, so that the half-bridge inverter converts DC power into AC power of a corresponding frequency. The PWM signal includes a PWMA signal and a PWMB signal. The PWMA signal and the PWMB signal are 180 degrees out of phase with each other, and the frequency and duty cycle are consistent.

[0042] In one embodiment of the present invention, the driving circuit further includes a transformer connected to the half-bridge inverter, and the transformer converts the voltage of the alternating current output by the half-bridge inverter into a voltage suitable for the ultrasonic transducer.

[0043] In one embodiment of the present invention, the PWM signal output by the controller is transmitted to the gate driver through an IO isolator, and the IO isolator is a high-speed optocoupler.

[0044] In one embodiment of the present invention, the controller is a DSP, FPGA, or MCU with a high-precision timer. The controller's timer IO generates two control signals, PWMA and PWMB. Because the subsequent stage utilizes a half-bridge inverter circuit, these two control signals are complementary, 180 degrees out of phase, with consistent frequency and duty cycle, and feature dead-zone control. The gate driver voltage range is 10-20V. To ensure safe operation of the controller, an IO isolator is used to isolate and protect the controller's IO. The IO isolator is a high-speed optocoupler that meets the frequency range requirements for the PWM control signal.

[0045] In one embodiment of the present invention, the driving circuit is connected to the ultrasonic transducer via an impedance matching circuit, and the impedance matching circuit includes a first inductor L2 connected in series with the ultrasonic transducer. Figure 5 As shown, the dashed box represents the equivalent circuit of the ultrasonic transducer. The ultrasonic transducer can be equivalent to a seventeenth resistor R17, a second capacitor C2, and a second inductor L2 connected in series with a first capacitor C1 in parallel. The first capacitor C1 is the static capacitance of the ultrasonic transducer, the seventeenth resistor R17 is a combination of a static resistor and a dynamic resistor, the second capacitor C2 is a dynamic capacitor, and the second inductor L2 is a dynamic inductor. Therefore, the ultrasonic transducer operates in a capacitive manner. If the drive circuit directly drives the ultrasonic transducer, reflected power will be generated, causing the device temperature to rise. Connecting the first inductor L1 in series with the ultrasonic transducer makes the ultrasonic transducer and the first inductor L1 resistive as a whole, ensuring normal operation of the ultrasonic transducer while also providing a certain filtering function.

[0046] In one embodiment of the present invention, Figure 4 As shown, the detection module includes a sampling resistor R0, a current sampling module, and a voltage sampling module. The sampling resistor R0 is connected in series with the ultrasonic transducer. The current sampling module samples the current of the sampling resistor R0, and the voltage sampling module samples the voltage of the ultrasonic transducer. The controller calculates the impedance of the ultrasonic transducer based on the data collected by the current sampling module and the voltage sampling module.

[0047] In one embodiment of the present invention, Figure 6As shown, the current sampling module collects the voltage at one end of the sampling resistor R0, and after voltage division and attenuation through the first resistor R1 and the second resistor R2, enters the first operational amplifier U1. One end of the second resistor R2 is connected between the first resistor R1 and the first operational amplifier U1, and the other end of the second resistor R2 is grounded. The current sampling module collects the voltage at the other end of the sampling resistor R0, and after voltage division and attenuation through the third resistor R3 and the fourth resistor R4, enters the second operational amplifier U2. One end of the fourth resistor R4 is connected between the third resistor R3 and the second operational amplifier U2, and the other end of the fourth resistor R4 is grounded. The signals output by the first and second op amps U1 and U2 pass through a differential amplifier circuit formed by a fifth resistor R5, a sixth resistor R6, a seventh resistor R7, an eighth resistor R8, and a third op amp U3 to obtain a voltage difference across the sampling resistor R0. The signal output by the first op amp U1 passes through the fifth resistor R5 and is input to the third op amp U3. One end of the sixth resistor R6 is connected between the fifth resistor R5 and the third op amp U3, and the other end of the sixth resistor R6 is grounded. The signal output by the second op amp U2 passes through the seventh resistor R7 and is input to the third op amp U3. One end of the eighth resistor R8 is connected between the seventh resistor R7 and the third op amp U3, and the other end of the eighth resistor R8 is connected to the output end of the third op amp U3. The third op amp U3 outputs the voltage difference to the ADC port of the controller, and the controller calculates the current flowing through the sampling resistor R0 based on the voltage difference and the resistance value of the sampling resistor R0. Since the sampling resistor R0 is connected in series with the ultrasonic transducer, the current flowing through the sampling resistor R0 is equal to the current flowing through the ultrasonic transducer.

[0048] In one embodiment of the present invention, Figure 7As shown, the voltage sampling module collects the voltage at one end of the ultrasonic transducer, and enters the fourth operational amplifier U4 after voltage division and attenuation through the ninth resistor R9 and the tenth resistor R10. One end of the tenth resistor R10 is connected between the ninth resistor R9 and the fourth operational amplifier U4, and the other end of the tenth resistor R10 is grounded; the voltage sampling module collects the voltage at the other end of the ultrasonic transducer, and enters the fifth operational amplifier U5 after voltage division and attenuation through the eleventh resistor R11 and the twelfth resistor R12. One end of the twelfth resistor R12 is connected between the eleventh resistor R11 and the fifth operational amplifier U5, and the other end of the twelfth resistor R12 is grounded. The signals output by the fourth and fifth op amps U4 and U5 pass through a differential amplifier circuit formed by a thirteenth resistor R13, a fourteenth resistor R14, a fifteenth resistor R15, a sixteenth resistor R16, and a sixth op amp U6, thereby obtaining a voltage difference across the ultrasonic wave. The signal output by the fourth op amp U4 passes through the thirteenth resistor R13 and is input to the sixth op amp U6. One end of the fourteenth resistor R14 is connected between the thirteenth resistor R13 and the sixth op amp U6, and the other end of the fourteenth resistor R14 is grounded. The signal output by the fifth op amp U5 passes through the fifteenth resistor R15 and is input to the sixth op amp U6. One end of the sixteenth resistor R16 is connected between the fifteenth resistor R15 and the sixth op amp U6, and the other end of the sixteenth resistor R16 is connected to the output end of the sixth op amp U6. The sixth op amp U6 outputs the voltage difference to an ADC port of a controller, and the controller calculates the voltage across the ultrasonic transducer based on the voltage difference.

[0049] The controller calculates the impedance of the ultrasonic transducer based on the voltage across the ultrasonic transducer and the current flowing through the ultrasonic transducer. The resonant frequency of the ultrasonic transducer corresponds to the impedance. Based on the impedance of the ultrasonic transducer, the difference between the resonant frequency of the ultrasonic transducer and a preset resonant frequency can be determined, thereby determining whether dirt is present on the object being cleaned.

[0050] In one embodiment of the present invention, Figure 4 As shown, it also includes a memory for storing the ultrasonic cleaning method proposed in the first aspect of the present invention, so that the ultrasonic cleaning device is suitable for running the ultrasonic cleaning method to clean the object to be cleaned.

[0051] In one embodiment of the present invention, a power input is further included. The power input provides power VDD1 to the controller via a power IC. The power IC also provides power VDD2 to the gate driver via an isolated power IC. The power input also provides power VCC to a half-bridge inverter circuit via a boost power IC. The half-bridge inverter circuit inverts power VCC into AC power.

[0052] In one embodiment of the present invention, Figure 4 As shown, a key detection circuit KEY is also included, and the key detection circuit KEY is used to switch the preset cleaning mode.

[0053] According to a third aspect of the present invention, there is provided a vehicle-mounted camera, comprising the ultrasonic cleaning device provided in the second aspect, wherein the object to be cleaned is a lens of the vehicle-mounted camera.

[0054] According to a fourth aspect of the present invention, a vehicle is provided, comprising the ultrasonic cleaning device provided in the second aspect or the vehicle-mounted camera provided in the third aspect, wherein the controller is connected to a CAN bus of the vehicle.

[0055] In the description of this application, the terms "first" and "second" are used for descriptive purposes only and should not be understood to indicate or imply relative importance or implicitly specify the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more features. In the description of this application, "plurality" means two or more, unless otherwise specifically defined.

[0056] In the above embodiments, the description of each embodiment has its own focus. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0057] The embodiments, implementation methods and related technical features of the present application can be combined and replaced with each other without conflict.

[0058] The above are only preferred embodiments of the present application and do not constitute any form of limitation to the present application. In the embodiments of the present application, the description of each embodiment has its own focus. For parts that are not described in detail in a certain embodiment, please refer to the relevant content of other embodiments. However, any brief modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present application without departing from the content of the technical solution of the present application are still within the scope of the technical solution of the present application.

Claims

1. An ultrasonic cleaning method, characterized in that, include: connecting an ultrasonic transducer to the object to be cleaned, wherein the ultrasonic transducer is suitable for resonating with the object to be cleaned; Acquiring characteristics of the ultrasonic transducer when the ultrasonic transducer resonates with the object to be cleaned; According to the feature, if the object to be cleaned is dirty, the object to be cleaned is cleaned.

2. The ultrasonic cleaning method according to claim 1, wherein The characteristic of the ultrasonic transducer includes at least one of a resonant frequency and an impedance.

3. The ultrasonic cleaning method according to claim 2, wherein: According to the feature, if the object to be cleaned is dirty, cleaning the object to be cleaned includes: The resonant frequency is obtained and compared with a preset resonant frequency. If the difference between the resonant frequency and the preset resonant frequency is greater than a first threshold, the object to be cleaned is dirty; the preset resonant frequency is the resonant frequency when the ultrasonic transducer resonates with the object to be cleaned when the object to be cleaned is not dirty.

4. The ultrasonic cleaning method according to claim 2, wherein: According to the feature, if the object to be cleaned is dirty, cleaning the object to be cleaned includes: The impedance is obtained and compared with a preset impedance. If the difference between the impedance and the preset impedance is greater than a second threshold, the object to be cleaned is dirty; the preset impedance is the impedance of the ultrasonic transducer when the ultrasonic transducer resonates with the object to be cleaned when the object to be cleaned is not dirty.

5. The ultrasonic cleaning method according to claim 1, wherein: According to the feature, if the object to be cleaned is dirty, cleaning the object to be cleaned includes: If the object to be cleaned is dirty, determining the type of the dirt according to the characteristics; According to the type of dirt, the object to be cleaned is cleaned in a corresponding manner.

6. The ultrasonic cleaning method according to claim 5, characterized in that The method of cleaning the object to be cleaned in a corresponding manner according to the type of dirt includes: According to the type of dirt, the ultrasonic transducer generates a corresponding vibration frequency to clean the object to be cleaned.

7. The ultrasonic cleaning method according to claim 1, wherein: According to the feature, if the object to be cleaned is dirty, cleaning the object to be cleaned includes: If the object to be cleaned is dirty, several preset cleaning modes are used to clean the object to be cleaned in sequence; the several preset cleaning modes are the resonant frequencies corresponding to several common dirts attached to the object to be cleaned.

8. The ultrasonic cleaning method according to claim 7, characterized in that: Several common Dirt includes but is not limited to one or more of water droplets, dust, mud spots and oil stains.

9. An ultrasonic cleaning device, characterized in that: include: Controller; an ultrasonic transducer connected to the object to be cleaned, wherein the ultrasonic transducer is adapted to resonate with the object to be cleaned; a detection module, configured to obtain characteristics of the ultrasonic transducer when the ultrasonic transducer resonates with the object to be cleaned; The controller determines whether the object to be cleaned is dirty according to the feature. If the object to be cleaned is dirty, the controller controls the ultrasonic transducer to resonate with the object to be cleaned to clean the object.

10. The ultrasonic cleaning device according to claim 9, characterized in that It also includes a driving circuit for inverting direct current into alternating current, the frequency of the alternating current being the resonant frequency of the ultrasonic transducer, and the controller is connected to the ultrasonic transducer via the driving circuit.

11. The ultrasonic cleaning device according to claim 10, characterized in that The drive circuit includes a gate driver and a half-bridge inverter circuit. The controller outputs a PWM signal to the gate driver. The gate driver controls the switching of the power tube in the half-bridge inverter circuit according to the PWM signal, so that the half-bridge inverter converts direct current into alternating current of corresponding frequency.

12. The ultrasonic cleaning device according to claim 11, characterized in that The PWM signal includes a PWMA signal and a PWMB signal. The PWMA signal and the PWMB signal have a phase difference of 180 degrees, and the frequency and duty cycle are consistent.

13. The ultrasonic cleaning device according to claim 11, characterized in that The driving circuit further includes a transformer connected to the half-bridge inverter, and the transformer converts the voltage of the alternating current output by the half-bridge inverter into a voltage adapted to the ultrasonic transducer.

14. The ultrasonic cleaning device according to claim 11, wherein The PWM signal output by the controller is transmitted to the gate driver through an IO isolator, and the IO isolator is a high-speed optocoupler.

15. The ultrasonic cleaning device according to claim 10, characterized in that The driving circuit is connected to the ultrasonic transducer via an impedance matching circuit, and the impedance matching circuit includes a first inductor connected in series with the ultrasonic transducer.

16. The ultrasonic cleaning device according to claim 9, characterized in that The detection module includes a sampling resistor, a current sampling module and a voltage sampling module. The sampling resistor is connected in series with the ultrasonic transducer. The current sampling module samples the current of the sampling resistor, and the voltage sampling module samples the voltage of the ultrasonic transducer.

17. The ultrasonic cleaning device according to claim 16, characterized in that The controller calculates the impedance of the ultrasonic transducer according to the data collected by the current sampling module and the voltage sampling module.

18. The ultrasonic cleaning device according to claim 9, characterized in that The ultrasonic cleaning device further comprises a memory for storing the ultrasonic cleaning method according to any one of claims 1 to 8, so that the ultrasonic cleaning device is suitable for running the ultrasonic cleaning method according to any one of claims 1 to 8 to clean the object to be cleaned.

19. A vehicle-mounted camera, characterized in that: The ultrasonic cleaning device comprises the ultrasonic cleaning device according to any one of claims 9 to 18, wherein the object to be cleaned is the lens of the vehicle-mounted camera.

20. A vehicle, characterized in that: The ultrasonic cleaning device comprises the ultrasonic cleaning device according to any one of claims 9 to 18 or the vehicle-mounted camera according to claim 19, wherein the controller is connected to a CAN bus of the vehicle.

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