Method and device for testing imaging quality of vehicle-mounted camera in salt mist high and low temperature environment

Abstract

The invention relates to the technical field of vehicle-mounted equipment testing devices, and discloses a method and a device for testing the imaging quality of a vehicle-mounted camera in a salt-spray high-low temperature environment, and the method comprises the steps: installing a to-be-tested camera on an adjustable platform in a salt-spray environment cabin, maintaining an optimal angle, and forming a closed environment; adjustable sodium chloride salt mist is provided by the salt mist generation system, and environmental parameters are controlled by the temperature and humidity generation control system; the salt mist environment chamber is provided with high-low-temperature-resistant high-transmittance glass and a self-cleaning device, and the glass is cleaned before soaking is finished; the camera is lightened through the lightening driving system, and the camera is adjusted to be centered with the test graphic card; by adjusting working conditions such as temperature, humidity, light environment and attitude angle, the camera is driven to shoot an image card image and transmit the image card image to the image analysis module; the module analyzes the image in real time and quantifies the imaging quality of the camera; the technical problem that the composite environment working condition cannot be simulated in the prior art is solved.

Description

Technical Field

[0001] This invention relates to the field of vehicle-mounted equipment testing devices, specifically to a method and device for testing the imaging quality of vehicle-mounted cameras under salt spray high and low temperature environments. Background Technology

[0002] As one of the core sensors in an environmental perception system, vehicle-mounted cameras play a crucial role in capturing real-time information about the vehicle's surroundings. In practical use, however, they face complex and ever-changing external environmental challenges. Especially in coastal areas or regions where de-icing agents are used in winter, vehicle-mounted cameras are constantly exposed to harsh environments of salt spray corrosion and fluctuating high and low temperatures, making them highly susceptible to environmental erosion. This can lead to a series of problems such as lens fogging, coating peeling, and circuit corrosion, ultimately resulting in decreased image quality or even malfunction, seriously threatening driving safety.

[0003] Although salt spray testing is widely used in automotive component testing to assess the corrosion resistance of materials, traditional salt spray testing methods have significant limitations in simulating the actual working environment of vehicle cameras.

[0004] Traditional salt spray tests often focus only on the impact of a single environmental factor, such as salt spray or high and low temperatures, on materials. This fails to fully reproduce the complex environmental conditions faced by vehicle cameras in actual use, resulting in significant discrepancies between test results and actual performance.

[0005] During salt spray testing, although the test chamber allows for real-time monitoring of sample corrosion through a transparent observation window, the high-transmittance glass window inside the salt spray environment chamber is highly susceptible to salt spray deposition, leading to decreased light transmittance and affecting image quality. Furthermore, the window cleaning process before each shot is not only time-consuming and labor-intensive, but also potentially has a significant impact on the test results due to temperature, humidity, and salt spray environment disturbances during the cleaning process. Summary of the Invention

[0006] The present invention aims to provide a method and apparatus for testing the imaging quality of vehicle-mounted cameras under salt spray high and low temperature environments, so as to solve the technical problem that the existing technology cannot simulate complex environmental conditions.

[0007] To achieve the above objectives, the present invention adopts the following technical solution: a method for testing the imaging quality of a vehicle-mounted camera under salt spray high and low temperature environments, comprising: S1. Install the camera under test on the angle-adjustable platform inside the salt spray environment chamber, keep the camera at the optimal angle for salt spray immersion, close the salt spray chamber to form a sealed environment, and close the darkroom door. S2. Drive the image acquisition card in the darkroom to light up the camera and confirm that the sample under test is in normal condition; S3. Provide sodium chloride salt spray with adjustable concentration and composition to the salt spray environment chamber through the salt spray generation system: The salt solution storage device of the salt spray generation system ensures the stability of the salt spray concentration during the test process, and the salt spray spraying device of the salt spray generation system can atomize the salt solution and spray it evenly on the sample surface. The salt spray chamber is connected to a temperature and humidity control system to ensure that the temperature and humidity of the camera immersion area meet the requirements and maintain a certain immersion time. S4. The salt spray environment chamber is equipped with high and low temperature resistant, high light transmittance glass and a self-cleaning device. Before taking pictures after immersion, the light transmittance glass is cleaned to remove the salt spray and water vapor deposits on the glass. S5. Light up the camera module under test through the camera lighting drive system, and adjust the adjustable mounting platform of the camera and the multi-degree-of-freedom adjustment device of the test chart to achieve alignment between the camera and the chart. S6. Adjust the temperature and humidity maintenance time and sequence in the environmental chamber through the temperature and humidity generation and control system; S7. Adjust the system configuration test light environment through the map card supplementary light source to provide all-weather map card shooting illumination; S8. Set the angle between the map card and the camera using the map card light source multi-degree-of-freedom attitude adjustment system, and preset the camera shooting angle and relative position; S9. The image acquisition card drives the camera to capture images of the image card while traversing salt spray, temperature, humidity, light environment, and attitude angle conditions, and transmits the images to the image analysis module. The image analysis module performs real-time analysis of the images and outputs the camera's resolution / resolution, distortion, chromatic aberration, and defocus curve parameters to quantify the imaging quality of the camera in salt spray high and low temperature environments.

[0008] The principle and advantages of this solution are as follows: This invention constructs a salt spray high and low temperature environment simulation system, placing the camera under test in this environment. A salt spray generation system provides adjustable concentration salt spray, while a temperature and humidity generation and control system controls the ambient temperature and humidity. An angle-adjustable platform adjusts the camera angle, and an image acquisition card drives the camera to capture images under different operating conditions. Finally, an image analysis module analyzes the images to quantify the camera's imaging quality. This solves the problem that existing technologies cannot simulate complex environmental conditions, comprehensively reproducing the complex environmental conditions such as salt spray, high and low temperatures, and humidity faced by vehicle-mounted cameras in actual use. This makes the test results closer to actual performance, improving the accuracy and reliability of the test.

[0009] Preferably, as an improvement, the self-cleaning step of the light-transmitting glass in S4 includes: Step S401: Establish environmental parameter baselines; Before the transparent glass self-cleans, the system records the initial salt spray concentration. ,temperature and humidity As a benchmark value, and to set the allowable fluctuation range; Step S402: Determining the cleanliness of the light-transmitting glass; The sharpness assessment module periodically captures images of the translucent glass window and calculates the sharpness index FI. The formula for calculating FI is as follows:

[0010] Where VOL is the sharpness based on edge sharpness, which is the gradient energy of the image; FE is the sharpness based on frequency domain analysis, which is the energy proportion of high-frequency components; and (1-G) is the sharpness based on light transmission uniformity, which is the gray-level distribution of the light-transmitting area. The FI is obtained by normalizing and weighting the three sharpness metrics. , , Determined based on the actual application scenario; Before the module under test takes a picture of the card, the self-cleaning mode of the light-transmitting glass is pre-selected based on the calculated FI value: light cleaning FI is greater than 0.9, standard cleaning FI is 0.9~0.7, and deep cleaning FI is less than 0.7. Step S403: Cleaning mode selection; Select the mode based on the clarity index and environmental stability requirements of salt spray, temperature, and humidity: select the light mode when there is light pollution and the environment is sensitive; select the standard mode when there is moderate pollution; select the deep mode when there is heavy pollution or in non-critical test stages. Step S404: Adjust parameters in real time; During the cleaning process, the environmental parameter analyzer continuously monitors changes in salt spray, temperature, and humidity, while the parameter regulator dynamically adjusts airflow pressure, duration, and electrostatic voltage to ensure that environmental fluctuations do not exceed limits. Step S405: Effect verification; After cleaning is completed, images are captured again to calculate the clarity index (FI). If the FI is still lower than the cleaning threshold, a second cleaning is initiated. The cleaning threshold is determined based on the original state of the transparent glass. This process is repeated until the clarity index (FI) of the transparent glass captured by the surveillance camera meets the cleaning threshold.

[0011] The beneficial effects of this improvement are as follows: By establishing environmental parameter benchmarks, determining the cleanliness of the transparent glass, selecting a cleaning mode, adjusting parameters in real time, and verifying the cleaning effect, a self-cleaning function for the transparent glass is achieved. It can automatically select an appropriate cleaning mode based on the degree of contamination of the transparent glass and the requirements for environmental stability, and dynamically adjust parameters during the cleaning process. This ensures the cleaning effect while minimizing the impact on salt spray, temperature, and humidity, guaranteeing the stability of the testing environment and improving the accuracy of the test results.

[0012] By calculating the Sharpness Index (FI), which comprehensively considers multiple factors such as edge sharpness, frequency domain analysis, and light transmission uniformity, the cleanliness of translucent glass can be more accurately determined, providing a reliable basis for selecting the appropriate cleaning mode. Choosing a cleaning mode based on the Sharpness Index and environmental stability requirements makes the cleaning process more scientific and reasonable, effectively cleaning the translucent glass while avoiding unnecessary environmental disturbance caused by over-cleaning.

[0013] Environmental parameters were monitored in real time and dynamically adjusted during the cleaning process to ensure that environmental fluctuations did not exceed limits, further improving the stability of the testing environment. Through effect verification and a secondary cleaning mechanism, the cleanliness of the transparent glass met testing requirements, improving the quality of image acquisition.

[0014] Preferably, as an improvement, the salt spray environment stability control method of S3 includes: Based on a multivariable coupled control model, the control inputs of spray volume, heating rate, and humidification volume are optimized to enable the system to quickly converge to the set value and remain stable. Through a laser particle size analyzer and temperature and humidity sensors placed near the camera under test, the salt spray mass concentration and particle diameter distribution, temperature, and humidity parameters in the salt spray chamber are monitored in real time. The data is transmitted to the control system in real time, and the salt spray, temperature, and humidity generating devices are linked to automatically adjust the spray concentration, temperature, and humidity to achieve closed-loop control. The multi-parameter coordinated control model of the salt spray environment chamber is as follows: C= (T, RH, spray volume); T= (C, RH, heating power); RH= (C, T, humidification rate); The system status is The control input is the salt spray volume. Heating power Humidification capacity The state equation is:

[0015] , , This is the coupled dynamic function between salt spray volume, heating power, and humidification volume under salt spray conditions.

[0016] The beneficial effects of this improvement are as follows: Based on a multivariable coupled control model, by real-time monitoring of the salt spray mass concentration, particle diameter distribution, temperature, and humidity parameters within the salt spray chamber, and by automatically adjusting the salt spray, temperature, and humidity generating devices, closed-loop control of the salt spray environment is achieved. This allows for rapid convergence to the set value and maintenance of stability, improving the stability and controllability of the salt spray environment and providing more accurate and reliable environmental conditions for testing vehicle-mounted cameras.

[0017] By establishing a multi-parameter coordinated control model among salt spray, temperature, and humidity, the interrelationships between these parameters were clarified, providing a theoretical basis for achieving closed-loop control. Parameters are monitored in real time using a laser particle size analyzer and sensors, and the data is transmitted to the control system. This system then adjusts the spray concentration, temperature, and humidity in a coordinated manner, enabling timely responses to environmental changes and ensuring the stability of environmental parameters.

[0018] Preferably, as an improvement, the cleaning methods of the glass self-cleaning system include airflow pulse cleaning and electrostatic anti-fog cleaning; airflow pulse cleaning involves spraying dry air onto the transparent glass to form a rotating vortex to remove condensate; electrostatic anti-fog cleaning involves coating the inner surface of the transparent glass with a transparent conductive oxide film, applying a pulsed DC voltage to generate a weak electric field, changing the orientation of water molecules to prevent condensation.

[0019] The beneficial effects of this improvement are: by combining airflow pulse cleaning and electrostatic anti-fog cleaning, salt spray deposits and water vapor condensation on transparent glass can be removed more effectively. Airflow pulse cleaning creates a rotating vortex by spraying dry air, which can powerfully remove condensation; electrostatic anti-fog cleaning changes the orientation of water molecules by applying a weak electric field to prevent water vapor condensation. The synergistic effect of the two improves the cleaning effect.

[0020] Different cleaning modes are selected based on the degree of contamination. The light mode only activates the electrostatic anti-fogging function and is suitable for lightly contaminated and environmentally sensitive situations. The standard mode combines electrostatic anti-fogging and short-duration airflow pulses and is suitable for moderate contamination. The deep mode performs a longer full-power cleaning and is suitable for heavily contaminated or non-critical testing phases. This tiered cleaning mode is more flexible and efficient and can meet the needs of different testing scenarios.

[0021] Preferably, as an improvement, the light mode only activates the electrostatic anti-fog function; the standard mode activates the electrostatic anti-fog function and combines it with a 1-2 second airflow pulse; and the deep mode activates the electrostatic anti-fog function and performs a 3-5 second full-power cleaning.

[0022] The beneficial effects of this improvement are: by enabling only the electrostatic anti-fog function, it can reduce environmental disturbance while ensuring the prevention of water vapor condensation. It is suitable for test scenarios with mild pollution and sensitive environment, which can meet the cleaning requirements and ensure the stability of the test environment to the greatest extent.

[0023] Activating the electrostatic anti-fog mode combined with a 1-2 second airflow pulse adds airflow pulse cleaning to the light mode, more effectively removing moderate contamination, suitable for general moderate contamination testing. Activating the electrostatic anti-fog mode with a 3-5 second full-power cleaning function thoroughly cleans light-transmitting glass for heavily contaminated or non-critical testing phases, ensuring image acquisition quality. These three modes allow for flexible selection based on different situations, improving the targeting and efficiency of cleaning.

[0024] Preferably, as an improvement, the salt spray environment chamber integrates a high-precision salt spray concentration sensor, a temperature and humidity probe, and an image clarity analysis module to monitor changes in environmental parameters within the salt spray environment chamber in real time, and dynamically adjusts cleaning parameters through an adaptive algorithm to ensure that fluctuations in environmental parameters are within the allowable range; The self-cleaning system compensation algorithm includes: when the cleaning airflow causes a decrease in local salt spray concentration, or deviations in temperature and humidity, the system initiates a compensation program. First, it calculates the concentration deviations ΔC, ΔT, and ΔH. Then, it adjusts the outputs of the salt spray generator, temperature generator, and humidity generator according to PID closed-loop control compensation. , , These are proportional coefficients, integral coefficients, and empirical coefficients, obtained by fitting actual test data. Salt spray concentration feedback adjustment:

[0025] in, To control and adjust the flow output of the spray pump; This refers to the deviation in salt spray concentration. , , The proportional, integral, and derivative gain coefficients for salt spray feedback regulation; Temperature feedback adjustment:

[0026] in, To control and regulate the temperature settings; To set the temperature; This is the measured temperature; , , For temperature feedback adjustment, the proportional, integral, and derivative gain coefficients are used. Humidity feedback adjustment:

[0027] in, To control and regulate the output of humidity; To set the humidity; This is the actual measured humidity. , , The humidity feedback adjustment ratio, integral, and derivative gain coefficients.

[0028] The beneficial effects of this improvement are: integrating a high-precision salt spray concentration sensor, temperature and humidity probe, and image clarity analysis module, it can monitor changes in environmental parameters within the salt spray environment chamber in real time and dynamically adjust cleaning parameters through an adaptive algorithm. This ensures that environmental parameter fluctuations remain within acceptable limits during the cleaning process, improving the stability and reliability of the testing environment. When the cleaning airflow causes a local decrease in salt spray concentration or deviations in temperature and humidity, the system initiates a compensation program, adjusting the outputs of the salt spray generator, temperature generator, and humidity generator according to PID closed-loop control. Through precise feedback adjustment, it can quickly restore the stability of environmental parameters and reduce the impact of cleaning operations on the testing environment.

[0029] Preferably, as an improvement, the S4 also includes a bidirectional airflow recovery mechanism, which provides a return channel for the clean airflow to be collected, dehydrated, and reused, and is equipped with a salt trap.

[0030] The benefits of this improvement are: setting up a return channel for clean airflow to collect and dehydrate it for reuse, effectively saving resources and reducing testing costs. Equipping the system with a salt trap prevents salt spray crystallization and diffusion, avoiding secondary pollution to the testing environment and equipment, and ensuring a clean and stable testing environment.

[0031] An imaging quality testing device for vehicle-mounted cameras under high and low temperature salt spray environments includes an environmental simulation system: A darkroom provides a testing environment free from external light interference; Humidity generating chamber, used to generate different humidity conditions; Temperature generating chambers are used to provide different temperature environments; Salt spray generator is used to generate salt spray environments of different concentrations. The salt spray environment chamber is connected to a humidity generator, a temperature generator, and a salt spray generator. The humidity generator is connected to the salt spray environment chamber via humidity inlet and outlet pipes to supply humidity conditions, the temperature generator is connected to the salt spray environment chamber via temperature inlet and outlet pipes to supply temperature conditions, and the salt spray generator is connected to the salt spray environment chamber via a salt spray generator to supply salt spray conditions, thus simulating the environment of salt spray, high and low temperatures, and humidity changes. The salt spray environment chamber is equipped with high and low temperature resistant transparent glass for observation. The chamber body is made of corrosion-resistant materials and has internal temperature and humidity sensors that can monitor and report environmental parameters in real time. The salt spray generator uses a salt spray spraying device installed circumferentially inside the salt spray environment chamber to evenly spray the salt solution generated inside the salt spray generation chamber into the chamber, simulating salt spray environments of different concentrations. The salt spray generator also uses laser particle size analyzers installed on opposite sides of the salt spray environment chamber to monitor the salt spray mass concentration and particle diameter distribution in the salt spray chamber in real time. Temperature control subsystem: By installing temperature sensors at the camera to be tested and at the outlet of the temperature inlet and outlet pipes, the temperature is monitored and adjusted to maintain the temperature environment inside the cabin and simulate various extreme temperature conditions. Humidity control subsystem: By installing humidity sensors at the camera to be tested and at the outlet of the humidity inlet and outlet pipes, the humidity control subsystem monitors, adjusts and maintains the humidity environment inside the chamber, and works together with the temperature control subsystem to simulate complex temperature and humidity conditions. An adjustable high-pressure jet module is used to enable the salt spray generator's salt spray device to spray salt spray at different angles and pressures, thus replicating the salt spray impact conditions during real road driving. A self-cleaning system for transparent glass is installed inside the salt spray environment chamber to prevent salt spray deposition. The self-cleaning system for transparent glass includes a composite airflow vortex cleaning subsystem and an electrostatic anti-fog coating. The closed-loop control system for environmental parameters integrates high-precision sensors to monitor the impact of cleaning operations on the environment inside the chamber in real time, and dynamically adjusts cleaning parameters through adaptive algorithms to ensure that environmental fluctuations are within the allowable range. The bidirectional airflow recovery mechanism collects and dehydrates the clean airflow through the return channel for reuse, and is equipped with a salt trap to prevent salt spray crystallization and diffusion.

[0032] The beneficial effects of this improvement are: through the synergistic effect of the darkroom chamber, humidity generating chamber, temperature generating chamber, salt spray generating chamber, and salt spray environment chamber, it is possible to accurately simulate the environment of salt spray, high and low temperatures, and humidity changes, providing comprehensive environmental conditions for the testing of vehicle-mounted cameras. The circumferentially arranged salt spray device and laser particle size analyzer can uniformly spray salt solution and monitor the salt spray mass concentration and particle diameter distribution in real time, ensuring accurate simulation of the salt spray environment.

[0033] Sensors are installed at the camera under test and at the inlet / outlet connection point of the inlet / outlet pipe to accurately monitor and adjust the temperature and humidity environment inside the chamber, simulating various complex conditions. This allows the salt spray device to spray salt spray at different angles and pressures, replicating the salt spray impact conditions experienced during real-world road driving, thus improving the realism and reliability of the test. A composite airflow vortex cleaning subsystem and an electrostatic anti-fog coating are incorporated to effectively prevent salt spray deposition and ensure the quality of image acquisition.

[0034] Integrating high-precision sensors and adaptive algorithms, it monitors the impact of cleaning operations on the chamber environment in real time, dynamically adjusting cleaning parameters to ensure environmental fluctuations remain within acceptable limits. Clean airflow is collected and dehydrated through a return channel for reuse, and a salt trap prevents salt mist crystallization and diffusion, conserving resources and maintaining a clean environment.

[0035] Preferably, as an improvement, an optical testing system is also included: The camera mounting adjustable platform is set up inside the salt spray environment chamber to install the camera under test and achieve multi-degree-of-freedom adjustment to ensure that the camera can be accurately aligned with the test chart. The multi-degree-of-freedom chart attitude adjustment system is set up in a darkroom box to adjust the position and angle of the test chart, simulating the shooting environment of the vehicle camera under different attitudes; The Tuka supplemental lighting source adjustment system is set up in a darkroom box to configure the test lighting environment and simulate all-weather lighting conditions, including different color temperatures, illuminance and spectral distributions; The camera lighting drive system connects to the camera outside the environmental chamber via a data cable, enabling remote lighting and shooting of the camera. It also receives the raw image data captured by the camera, performs analog-to-digital conversion, and transmits the data to the image analysis module through an interface.

[0036] The benefits of this improvement are as follows: The adjustable camera mounting platform allows for multi-degree-of-freedom adjustment, ensuring precise alignment of the camera with the test chart and improving testing accuracy. Adjusting the position and angle of the test chart simulates the shooting environment of an onboard camera in different postures, making the test closer to real-world conditions. Configuring the test lighting environment simulates all-weather lighting conditions, including different color temperatures, illuminance, and spectral distributions, comprehensively evaluating the camera's imaging performance under varying lighting conditions. It enables remote camera activation and driving for shooting, and receives raw image data, completing analog-to-digital conversion and data transmission, facilitating operation and data processing.

[0037] Preferably, as an improvement, it also includes an image acquisition and analysis system: The image acquisition card receives image data captured by the camera and transmits it to the image analysis module; The image analysis module performs real-time analysis on the acquired images, calculates and outputs quantitative indicators of image quality, including resolution, distortion, chromatic aberration, and defocus curve.

[0038] The benefits of this improvement are: it receives image data captured by the camera and transmits it to the image analysis module, ensuring accurate transmission of image data. Real-time analysis of the acquired images provides an objective basis for evaluating camera performance. Attached Figure Description

[0039] Figure 1This is an overall flowchart of an embodiment of the present invention.

[0040] Figure 2 This is a flowchart of the self-cleaning process for transparent glass.

[0041] Figure 3 This is a schematic diagram of the overall structure of an embodiment of the present invention.

[0042] Figure 4 This is a schematic diagram of the darkroom.

[0043] Figure 5 This is a schematic diagram of a glass self-cleaning system.

[0044] The reference numerals in the accompanying drawings include: darkroom 1, environmental chamber 2, temperature and humidity control system 3, salt spray generator 4, camera 5, attitude adjustable platform 6, light-transmitting glass 7, chart 8, multi-degree-of-freedom adjustment mechanism 9, salt spray spray device 10, laser particle size analyzer 11, and vortex air nozzle 12. Detailed Implementation

[0045] The following detailed description illustrates the specific implementation method: Example A method and apparatus for testing the imaging quality of a vehicle-mounted camera under high and low temperature salt spray conditions, comprising a method for testing the imaging quality of a vehicle-mounted camera under high and low temperature salt spray conditions and an apparatus for testing the imaging quality of a vehicle-mounted camera under high and low temperature salt spray conditions.

[0046] This solution constructs a composite environment simulation system to achieve coupled testing of multiple factors such as salt spray corrosion, temperature shock, humidity change, lighting environment change, shooting angle adjustment, and self-cleaning of light-transmitting glass. It can accurately and automatically evaluate the imaging stability of vehicle cameras in harsh environments.

[0047] The basics are as follows: Figure 1 As shown, a method for testing the imaging quality of a vehicle-mounted camera under high and low temperature salt spray conditions includes: S1. Install the camera under test on the angle-adjustable platform inside the salt spray environment chamber, keep the camera at the optimal angle for salt spray immersion, close the salt spray chamber to form a sealed environment, and close the darkroom door. S2. Drive the image acquisition card in the darkroom to light up the camera and confirm that the sample under test is in normal condition; S3. Provide sodium chloride salt spray with adjustable concentration and composition to the salt spray environment chamber through the salt spray generation system: The salt solution storage device of the salt spray generation system ensures the stability of the salt spray concentration during the test process, and the salt spray spraying device of the salt spray generation system can atomize the salt solution and spray it evenly on the sample surface. The salt spray chamber is connected to a temperature and humidity control system to ensure that the temperature and humidity of the camera immersion area meet the requirements and maintain a certain immersion time. S4. The salt spray environment chamber is equipped with high and low temperature resistant, high light transmittance glass and a self-cleaning device. Before taking pictures after immersion, the light transmittance glass is cleaned to remove the salt spray and water vapor deposits on the glass. S5. Light up the camera module under test through the camera lighting drive system, and adjust the adjustable mounting platform of the camera and the multi-degree-of-freedom adjustment device of the test chart to achieve alignment between the camera and the chart. S6. Adjust the temperature and humidity maintenance time and sequence in the environmental chamber through the temperature and humidity generation and control system; S7. Adjust the system configuration test light environment through the map card supplementary light source to provide all-weather map card shooting illumination; S8. Set the angle between the map card and the camera using the map card light source multi-degree-of-freedom attitude adjustment system, and preset the camera shooting angle and relative position; S9. The image acquisition card drives the camera to capture images of the image card while traversing salt spray, temperature, humidity, light environment, and attitude angle conditions, and transmits the images to the image analysis module. The image analysis module performs real-time analysis of the images and outputs the camera's resolution / resolution, distortion, chromatic aberration, and defocus curve parameters to quantify the imaging quality of the camera in salt spray high and low temperature environments.

[0048] Among them, as attached Figure 2 As shown, the self-cleaning steps for the transparent glass in S4 include: Step S401: Establish environmental parameter baselines; Before the transparent glass self-cleans, the system records the initial salt spray concentration. ,temperature and humidity As a benchmark value, and setting an allowable fluctuation range, for example ±1% ±0.5℃ ±2%RH.

[0049] Step S402: Determining the cleanliness of the light-transmitting glass; The sharpness assessment module periodically captures images of the translucent glass window and calculates the sharpness index FI. The formula for calculating FI is as follows:

[0050] Where VOL is the sharpness based on edge sharpness, which is the gradient energy of the image; FE is the sharpness based on frequency domain analysis, which is the energy proportion of high-frequency components; and (1-G) is the sharpness based on light transmission uniformity, which is the gray distribution of the light transmission area.

[0051] The FI is obtained by normalizing and weighting the three sharpness metrics. , , Based on the actual application scenario, this embodiment is... 0.3 0.3 It is 0.4.

[0052] Before the module under test takes a picture of the card, the self-cleaning mode of the light-transmitting glass is pre-selected based on the calculated FI value: light cleaning (FI > 0.9), standard cleaning (0.9~0.7), and deep cleaning (FI < 0.7). Among them, the light mode only enables the electrostatic anti-fog function; the standard mode enables the electrostatic anti-fog function and combines it with a 1-2 second airflow pulse; the deep mode enables the electrostatic anti-fog function and performs a 3-5 second full-power cleaning.

[0053] Step S403: Cleaning mode selection; Select the mode based on the clarity index and environmental stability requirements of salt spray, temperature, and humidity: select the light mode when there is light pollution and the environment is sensitive; select the standard mode when there is moderate pollution; and select the depth mode when there is heavy pollution or in non-critical test stages.

[0054] Step S404: Adjust parameters in real time; During the cleaning process, the environmental parameter analyzer continuously monitors changes in salt spray, temperature, and humidity, while the parameter regulator dynamically adjusts airflow pressure, duration, and electrostatic voltage to ensure that environmental fluctuations do not exceed limits. The airflow pressure adjustment range is 0.15MPa-0.25MPa, the duration adjustment range is 1s-5s, and the electrostatic voltage adjustment range is 12V-24V.

[0055] Step S405: Effect verification; After cleaning is completed, images are collected again to calculate the clarity index (FI). If the FI is still lower than the cleaning threshold, a second cleaning is initiated. The cleaning threshold is determined based on the original state of the transparent glass. In this embodiment, the cleaning threshold is 0.95. This process is repeated until the clarity index (FI) of the transparent glass collected by the transparent glass monitoring camera meets the cleaning threshold.

[0056] This plan, as attached Figure 3 and attached Figure 4 As shown, a temperature and humidity salt spray environment chamber 2 is arranged in a darkroom 1 environment. The temperature and humidity salt spray environment chamber is connected to a temperature and humidity control system 3 and a salt spray generator 4 to simulate different concentrations of salt spray, temperature, and humidity environments inside the temperature and humidity salt spray environment chamber 2. A camera 5 is clamped and fixed on an adjustable platform 6 inside the temperature and humidity salt spray environment chamber. A drive module is set outside the temperature and humidity salt spray environment chamber to connect to the camera. The temperature and humidity salt spray environment chamber is made of light-transmitting glass 7, and a diagram 8 is set on the top of the temperature and humidity salt spray environment chamber.

[0057] This method for testing the imaging quality of vehicle-mounted cameras involves setting up a temperature, humidity, and salt spray environment chamber within a darkroom setting. An integrated environmental control system simulates different salt spray concentrations, temperature, and humidity conditions. A multi-degree-of-freedom adjustment mechanism 9 ensures precise alignment between the camera 7 and the test chart 8. An automated image analysis system quantifies the imaging quality parameters. Its technical features are: (1) Construct a four-dimensional test environment of "salt spray + temperature + humidity + light" to realistically simulate coastal, winter and all-weather working conditions; (2) The salt spray environment chamber where the camera is installed is equipped with transparent glass and a self-cleaning system to ensure the accuracy of the camera images during the entire testing process. (3) The camera mounting platform can be finely adjusted to achieve initial test position centering in conjunction with the map card light source adjustment system; the relative angle between the test map card and the camera is adjusted by the multi-degree-of-freedom map card attitude adjustment system to simulate the shooting of the map card under different angle states of the vehicle camera; (4) The camera is connected to the lighting drive system outside the environmental cabin via a data cable. The camera can be driven to take pictures of the card at a specific time point and transmit the images to the image analysis module. (5) Establish a fully automated testing process to achieve integrated operation of environmental simulation, image acquisition and data analysis.

[0058] The salt spray environment stability control methods for S3 include: Based on a multivariable coupled control model, the control inputs of spray volume, heating rate, and humidification are optimized to enable the system to quickly converge to the set value and remain stable. Through a laser particle size analyzer and temperature and humidity sensors placed near the camera under test, the salt spray mass concentration, particle diameter distribution, temperature, and humidity parameters in the salt spray chamber are monitored in real time. The data is transmitted to the control system in real time, and the salt spray, temperature, and humidity generating devices are linked to automatically adjust the spray concentration, temperature, and humidity to achieve closed-loop control.

[0059] The multi-parameter coordinated control model of the salt spray environment chamber is as follows: C= (T, RH, spray volume); T= (C, RH, heating power); RH= (C, T, humidification rate); The system status is The control input is the salt spray volume. Heating power Humidification capacity The state equation is:

[0060] , , This is the coupled dynamic function between salt spray volume, heating power, and humidification volume under salt spray conditions.

[0061] The glass self-cleaning system achieves a balance between efficient cleaning of the observation window and stability of the experimental environment through a multi-modal collaborative cleaning mechanism. The cleaning methods include pulsed airflow cleaning and electrostatic anti-fogging cleaning. Pulsed airflow cleaning involves spraying dry air onto the transparent glass to create a rotating vortex that removes condensation. Electrostatic anti-fogging cleaning involves coating the inner surface of the transparent glass with a transparent conductive oxide (ITO) film and applying a pulsed DC voltage to generate a weak electric field, altering the orientation of water molecules to prevent condensation.

[0062] The salt spray environment chamber integrates a high-precision salt spray concentration sensor, temperature and humidity probes, and an image clarity analysis module. It monitors changes in environmental parameters within the chamber in real time and dynamically adjusts cleaning parameters using an adaptive algorithm to ensure fluctuations remain within acceptable limits. The environmental parameter fluctuation ranges are: salt spray concentration change ≤ ±1%, temperature fluctuation ≤ ±0.5℃, and humidity change ≤ ±2%RH.

[0063] The self-cleaning system compensation algorithm includes the following: when the cleaning airflow causes a decrease in local salt spray concentration, or deviations in temperature and humidity, the system initiates a compensation program. First, it calculates the concentration deviations ΔC, ΔT, and ΔH. Then, it adjusts the outputs of the salt spray generator, temperature generator, and humidity generator according to PID closed-loop control compensation. , , The proportional coefficient, integral coefficient, and empirical coefficient are obtained by fitting actual test data.

[0064] Salt spray concentration feedback adjustment:

[0065] in, To control and adjust the flow output of the spray pump; Salt spray concentration deviation (set value - measured value); , , Salt spray feedback adjustment ratio, integral, and derivative gain coefficients (obtained from actual testing); Temperature feedback adjustment:

[0066] in, Control and adjust the temperature settings; Set the temperature (e.g., 35℃); Measured temperature (from temperature sensor); , , Temperature feedback adjustment ratio, integral, and derivative gain coefficients (obtained from actual testing); Humidity feedback adjustment:

[0067] in, Control the output of humidity regulation; Set the humidity (e.g., 95%RH); Measured humidity (from humidity sensor); , , Humidity feedback adjustment ratio, integral, and derivative gain coefficients (obtained from actual testing).

[0068] The S4 also features a bidirectional airflow recovery mechanism, which collects and dehydrates the clean airflow for reuse, preventing an increase in internal air pressure and humidity. The system is equipped with a salt trap to prevent salt mist crystallization and diffusion during the cleaning process.

[0069] This method selects an appropriate cleaning mode based on the condition of the glass as captured by a camera next to the high-transmittance glass, combined with the experimental stage and the degree of glass contamination: light mode (electrostatic anti-fogging only), standard mode (electrostatic + short-term airflow), and deep mode (full-power cleaning). This minimizes interference with the experiment while ensuring the image quality of the target board. A complete closed-loop control process is formed through steps such as establishing environmental parameter benchmarks, determining cleaning needs, selecting cleaning modes, real-time parameter adjustment, and effect verification.

[0070] An imaging quality testing device for vehicle-mounted cameras under high and low temperature salt spray environments includes an environmental simulation system, an optical testing system, and an image acquisition and analysis system.

[0071] As attached Figure 3 Appendix Figure 4 and appendix Figure 5 As shown, the environmental simulation system includes: The darkroom, or darkroom 1, provides a testing environment free from external light interference, ensuring the accuracy of test results.

[0072] A humidity generating chamber is used to create different humidity conditions.

[0073] Temperature generating chambers are used to provide different temperature environments.

[0074] Salt spray generator is used to generate salt spray environments of different concentrations.

[0075] Salt spray environment chamber 2, including a humidity generator, a temperature generator, and a salt spray generator, is connected to the salt spray environment chamber. Specifically, the humidity generator supplies humidity conditions via humidity inlet and outlet pipes, the temperature generator supplies temperature conditions via temperature inlet and outlet pipes, and the salt spray generator supplies salt spray conditions via a salt spray generator. This simulates environments with salt spray, high and low temperatures, and humidity variations.

[0076] The salt spray environment chamber is equipped with high and low temperature resistant transparent glass 7 for observation. The chamber body is made of corrosion resistant materials and is equipped with temperature and humidity sensors inside, which can monitor and report environmental parameters in real time.

[0077] The salt spray generator 4 uses a salt spray injection device 10 installed circumferentially inside the salt spray environment chamber to uniformly spray the salt solution generated in the salt spray generation chamber into the chamber, simulating salt spray environments of different concentrations. The salt spray generator also uses laser particle size analyzers 11 installed on opposite sides of the salt spray environment chamber to monitor the salt spray mass concentration and particle diameter distribution in real time.

[0078] Temperature control subsystem: Temperature sensors are installed at the camera to be tested and at the outlet of the temperature inlet and outlet pipes to monitor and adjust the temperature environment inside the cabin, simulating various extreme temperature conditions.

[0079] Humidity control subsystem: By installing humidity sensors at the camera to be tested and at the outlet of the humidity inlet and outlet pipes, the humidity environment inside the cabin is monitored, adjusted and maintained. It works together with the temperature control subsystem to simulate complex temperature and humidity conditions.

[0080] An adjustable high-pressure jet module is used to enable the salt spray generator's salt spray injection device to spray salt spray at different angles and pressures, replicating the salt spray impact conditions during real road driving.

[0081] A self-cleaning system for transparent glass is installed inside the salt spray environment chamber to prevent salt spray buildup. The system includes a composite airflow vortex cleaning subsystem and an electrostatic anti-fog coating.

[0082] As attached Figure 4 Appendix Figure 5As shown, the composite airflow vortex cleaning subsystem employs multiple sets of precision nozzles arranged in a ring to spray dry air, forming a rotating vortex to remove salt spray condensate from the observation window. It also utilizes three sets of vortex air nozzles arranged in a ring, with each set of nozzles 12 uniformly positioned at the same incident angle of 120 degrees to spray dry air onto the observation window surface, creating a standard annular vortex to remove condensate. To meet different cleanliness requirements, it can provide localized enhanced cleaning to address similar agglomerated contaminants. The incident angles of the three sets of vortex air nozzles in this composite airflow vortex cleaning subsystem can be independently adjusted to adapt to the optimal vortex pattern.

[0083] An electrostatic anti-fog coating is used; the inner surface of the observation window is coated with a transparent conductive oxide (ITO) film. Applying a pulsed DC voltage generates a weak electric field, which alters the orientation of water molecules to prevent condensation. Compared to conventional heating films, energy consumption is reduced by 80% without affecting the internal temperature of the chamber.

[0084] The closed-loop environmental parameter control system integrates high-precision sensors, such as temperature sensors, humidity sensors, and laser particle size analyzers, to monitor the impact of cleaning operations on the environment inside the chamber in real time. It dynamically adjusts cleaning parameters through adaptive algorithms to ensure that environmental fluctuations are within the allowable range.

[0085] The two-way airflow recovery mechanism collects clean airflow through the return channel, dehydrates it, and reuses it, avoiding an increase in air pressure and humidity inside the chamber. It is also equipped with a salt trap to prevent salt mist crystallization and diffusion.

[0086] As attached Figure 4 and attached Figure 5 As shown, the optical testing system includes: The adjustable camera clamping platform, also known as the attitude-adjustable platform 6, is installed inside the salt spray environment chamber. It is used to mount the camera under test 5 and allows for multi-degree-of-freedom adjustment, ensuring the camera can be accurately aligned with the test chart 8. The adjustable camera clamping platform is a three-degree-of-freedom clamping platform, supporting pitch ±30° and rotation 360° adjustment. Furthermore, the platform has multiple camera clamping positions, each with radially movable mounting rails to facilitate camera installation and adjustment.

[0087] The multi-degree-of-freedom chart attitude adjustment system is set up in the darkroom box. Through the multi-degree-of-freedom adjustment mechanism 9, it is used to adjust the position and angle of the test chart to simulate the shooting environment of the vehicle camera under different attitudes.

[0088] The Tuka supplemental lighting system, located in a darkroom, is used to configure the test lighting environment and simulate all-weather lighting conditions, including different color temperatures, illuminance, and spectral distributions.

[0089] The camera lighting drive system connects to the camera outside the environmental chamber via a data cable, enabling remote lighting and shooting of the camera. It also receives the raw image data captured by the camera, performs analog-to-digital conversion, and transmits the data to the image analysis module through an interface.

[0090] Image acquisition and analysis system, including: The image acquisition card receives image data captured by the camera and transmits it to the image analysis module.

[0091] The image analysis module performs real-time analysis on the acquired images, calculates and outputs quantitative indicators of image quality, such as resolution, distortion, chromatic aberration, and defocus curve.

[0092] The device adopts a modular design, with each subsystem and module being independently controllable and able to work collaboratively; it is equipped with a corrosion-resistant and light-transmitting observation window and an automatic cleaning device; it has a built-in standard communication interface that supports interfacing with the MES system; the transparent glass top cover of the salt spray environment chamber is designed to be opened and closed, allowing the test samples to be removed after the test is completed.

[0093] This embodiment illustrates the salt spray high and low temperature environment test of a certain model of front-view vehicle camera. The test object is a 3-megapixel CMOS front-view FOV150°, FOV90° wide-angle camera module, installed in a temperature and humidity salt spray environment chamber on a three-degree-of-freedom mounting platform. This camera mounting adjustable platform supports pitch ±30° and rotation 360°. When the darkroom is closed, the internal basic illuminance is ≤0.1Lux, and the test parameters are set as follows: Salt spray environment: 5% NaCl solution, spray rate 1.5 mL / h. The angle between the spray angle of the camera under test and the spray angle is 45°. Temperature cycling: -30℃ (4h) → 25℃ (2h) → 85℃ (4h), conversion rate 10℃ / min, cycle period 48h; Humidity control: 30%RH in low temperature range, 95%RH in high temperature range; Glass self-cleaning system: After the salt spray immersion is completed and before the camera takes a picture, the system sets up self-cleaning of the transparent glass to ensure that the light transmittance of the glass window for camera shooting remains above 95%.

[0094] Test chart: ISO12233 resolution test chart, taken at equal intervals with 10% field of view in the horizontal, vertical and diagonal directions; Supplemental lighting intensity: Parallel light tube supplemental lighting, color temperature set to 6500K, center illuminance of test chart set to 1000Lux, 10Lux, and 2Lux respectively, brightness uniformity 93%; Cabin temperature during camera recording: The temperature control system is set to -40℃, -20℃, 0℃, 20℃, 40℃, 60℃, 85℃, and 95℃. The system is set to complete automated shooting, transmit the captured images to the image analysis module for SFR analysis, generate analysis results and store the raw data; The image analysis module measured the following: SFR ≥ 0.65@Ny / 2 in the central area; SFR ≥ 0.43@Ny / 2 in 70% field of view; and under 2Lux low illumination, SFR in both the YUV and Raw domains was not less than 60% of the specified value. The test data shows that the camera can still maintain good imaging performance under extreme salt spray and high / low temperature environments.

[0095] The method of this invention was used to conduct high and low temperature tests on a batch of six fisheye cameras with FOV 180° and FOV 130° of surround view system after immersion in a salt spray environment.

[0096] Six modules were installed on the adjustable camera mounting platform and connected to the camera lighting drive system outside the salt spray environment chamber via data cables.

[0097] The sample was immersed in a salt spray environment chamber at a salt spray concentration of 8% + 85℃ for 120 hours under high humidity (95%RH). The transparent glass was cleaned using a self-cleaning system. The temperature control system was set to -40℃, -20℃, 0℃, 20℃, 40℃, 60℃, 85℃, and 95℃, with a humidity of 70%RH. The color temperature of the collimator supplemental light was 6500K, and the illuminance of the center supplemental light on the test chart was set to 1000Lux. The camera was aligned with the center of the chart, and the camera was driven to take pictures of the chart at equal intervals along the horizontal, vertical, and diagonal directions, each at 10% of the field of view. The images were then transmitted to the image analysis module for distortion, resolution, and defocus analysis. The statistical analysis results compared with the design state showed: edge resolution decreased by 13.5%, which was attributed to image quality degradation caused by salt spray crystallization at the wide-angle edges; distortion increased by 3.4%, which was attributed to increased optical distortion due to high-temperature salt spray impact; and low-temperature defocus increased by 0.15mm, which was attributed to displacement of the lens assembly caused by thermal expansion and contraction of the camera module materials.

[0098] Compared to existing technologies, this self-cleaning system for transparent glass maintains the light transmittance of the observation window at over 90% (traditional methods typically result in less than 70%), with salt spray concentration changes during the cleaning process less than 1%, temperature fluctuations controlled within ±0.3℃, and humidity changes not exceeding ±1.5%RH. This fully meets the stringent requirements of standards such as ASTM B117 and ISO 9227 for the stability of the salt spray testing environment. Furthermore, the system can achieve continuous testing observations for up to 1000 hours without manual intervention, significantly improving the automation level and reliability of salt spray testing results.

[0099] This invention can effectively identify typical failures of cameras with different architectures under salt spray and high / low temperature environments, providing quantitative basis for improving sealing design and optical coating. Simultaneously, this invention can perform attenuation tests on key parameters of multiple samples, ensuring the consistency of the testing system while significantly improving testing efficiency. Compared to traditional single-factor testing methods, this invention integrates salt spray, high / low temperature, humidity, lighting environment, test angle, and number of test samples into an automated test, improving efficiency several times over while shortening the development and testing cycle, reducing interference factors introduced by human intervention, saving testing costs, facilitating the statistical analysis of product consistency, and providing a reference basis for improving production processes.

[0100] The above descriptions are merely embodiments of the present invention, and common knowledge such as specific technical solutions and / or characteristics are not described in detail here. It should be noted that those skilled in the art can make various modifications and improvements without departing from the technical solutions of the present invention, and these should also be considered within the scope of protection of the present invention. These modifications and improvements will not affect the effectiveness of the implementation of the present invention or the practicality of the patent. The scope of protection claimed in this application should be determined by the content of its claims, and the specific embodiments described in the specification can be used to interpret the content of the claims.

Claims

1. A method for testing imaging quality of a vehicle-mounted camera in a salt spray high-low temperature environment, characterized in that, include: S1. Install the camera under test on the angle-adjustable platform inside the salt spray environment chamber, keep the camera at the optimal angle for salt spray immersion, close the salt spray chamber to form a sealed environment, and close the darkroom door. S2. Drive the image acquisition card in the darkroom to light up the camera and confirm that the sample under test is in normal condition; S3. Provide sodium chloride salt spray with adjustable concentration and composition to the salt spray environment chamber through the salt spray generation system: The salt solution storage device of the salt spray generation system ensures the stability of the salt spray concentration during the test process, and the salt spray spraying device of the salt spray generation system can atomize the salt solution and spray it evenly on the sample surface. The salt spray chamber is connected to a temperature and humidity control system to ensure that the temperature and humidity of the camera immersion area meet the requirements and maintain a certain immersion time. S4. The salt spray environment chamber is equipped with high and low temperature resistant, high light transmittance glass and a self-cleaning device. Before taking pictures after immersion, the light transmittance glass is cleaned to remove the salt spray and water vapor deposits on the glass. S5. Light up the camera module under test through the camera lighting drive system, and adjust the adjustable mounting platform of the camera and the multi-degree-of-freedom adjustment device of the test chart to achieve alignment between the camera and the chart. S6. Adjust the temperature and humidity maintenance time and sequence in the environmental chamber through the temperature and humidity generation and control system; S7. Adjust the system configuration test light environment through the map card supplementary light source to provide all-weather map card shooting illumination; S8. Set the angle between the map card and the camera using the map card light source multi-degree-of-freedom attitude adjustment system, and preset the camera shooting angle and relative position; S9. The image acquisition card drives the camera to capture images of the image card while traversing working conditions such as salt spray, temperature, humidity, light environment, and attitude angle, and transmits the images to the image analysis module. The image analysis module performs real-time analysis of the image and outputs the camera's resolution, distortion, chromatic aberration, and defocus curve parameters, quantifying the camera's imaging quality under salt spray and high / low temperature environments.

2. The method according to claim 1, wherein, The self-cleaning step of the light-transmitting glass in S4 includes: Step S401: Establish environmental parameter baselines; The initial salt mist concentration is recorded by the system as a reference value before the self-cleaning of the light-transmitting glass , temperature and humidity , and a fluctuation range is set. Step S402: Determining the cleanliness of the light-transmitting glass; The sharpness assessment module periodically captures images of the translucent glass window and calculates the sharpness index FI. The formula for calculating FI is as follows: Where VOL is the sharpness based on edge sharpness, which is the gradient energy of the image; FE is the sharpness based on frequency domain analysis, which is the energy proportion of high-frequency components; and (1-G) is the sharpness based on light transmission uniformity, which is the gray-level distribution of the light-transmitting area. The three clarity indicators are normalized and fused by weighting to obtain FI, usually , , Determined according to the actual application scenario; Before the module under test takes a picture of the card, the self-cleaning mode of the light-transmitting glass is pre-selected based on the calculated FI value: light cleaning FI is greater than 0.9, standard cleaning FI is 0.9~0.7, and deep cleaning FI is less than 0.

7. Step S403: Cleaning mode selection; Select the mode based on the clarity index and environmental stability requirements of salt spray, temperature, and humidity: select the light mode when there is light pollution and the environment is sensitive; select the standard mode when there is moderate pollution; select the deep mode when there is heavy pollution or in non-critical test stages. Step S404: Adjust parameters in real time; During the cleaning process, the environmental parameter analyzer continuously monitors changes in salt spray, temperature, and humidity, while the parameter regulator dynamically adjusts airflow pressure, duration, and electrostatic voltage to ensure that environmental fluctuations do not exceed limits. Step S405: Effect verification; After cleaning is completed, images are captured again to calculate the clarity index (FI). If the FI is still lower than the cleaning threshold, a second cleaning is initiated. The cleaning threshold is determined based on the original state of the transparent glass. This process is repeated until the clarity index (FI) of the transparent glass captured by the surveillance camera meets the cleaning threshold.

3. The method according to claim 2, wherein the method is a method for testing the imaging quality of a vehicle-mounted camera in a salt spray high-low temperature environment. The salt spray environment stability control method of S3 includes: Based on a multivariable coupled control model, the control inputs of spray volume, heating rate, and humidification volume are optimized to enable the system to quickly converge to the set value and remain stable. Through a laser particle size analyzer and temperature and humidity sensors placed near the camera under test, the salt spray mass concentration and particle diameter distribution, temperature, and humidity parameters in the salt spray chamber are monitored in real time. The data is transmitted to the control system in real time, and the salt spray, temperature, and humidity generating devices are linked to automatically adjust the spray concentration, temperature, and humidity to achieve closed-loop control. The multi-parameter coordinated control model of the salt spray environment chamber is as follows: C= (T, RH, spray volume); T= (C, RH, heating power); RH = 100 - (T - 20) / 5 (C, T, humidification amount); System state is , control input is salt spray injection amount , heating power , humidification amount , state equation is: , , is a coupling dynamics function among the salt spray spraying amount, the heating power, and the humidifying amount in the salt spray environment.

4. The salt spray high and low temperature environment vehicle-mounted camera imaging quality test method according to claim 3, characterized in that: The cleaning methods of the glass self-cleaning system include airflow pulse cleaning and electrostatic anti-fog cleaning; airflow pulse cleaning involves spraying dry air into the transparent glass to form a rotating vortex to remove condensation; electrostatic anti-fog cleaning involves coating the inner surface of the transparent glass with a transparent conductive oxide film, applying a pulsed DC voltage to generate a weak electric field, changing the orientation of water molecules to prevent condensation.

5. The salt spray high and low temperature environment vehicle-mounted camera imaging quality test method according to claim 4, characterized in that: Light mode activates only the electrostatic anti-fog function; Standard mode activates the electrostatic anti-fog function and combines it with a 1-2 second airflow pulse; Deep mode activates the electrostatic anti-fog function and performs a 3-5 second full-power cleaning.

6. The salt spray high and low temperature environment vehicle-mounted camera imaging quality test method according to claim 5, characterized in that, The salt spray environment chamber integrates a high-precision salt spray concentration sensor, temperature and humidity probe, and image clarity analysis module to monitor changes in environmental parameters within the salt spray environment chamber in real time. It also dynamically adjusts cleaning parameters through an adaptive algorithm to ensure that fluctuations in environmental parameters are within the allowable range. The self-cleaning system compensation algorithm comprises: when the cleaning airflow causes local salt mist concentration to decrease, temperature and humidity to deviate, the system starts a compensation program, first calculates concentration deviation ΔC, ΔT and ΔH, and then adjusts the output of the salt mist generator, the temperature generator and the humidity generator according to PID closed-loop control compensation, wherein 、 、 are proportional coefficients, integral coefficients and experience coefficients, which are obtained by combining actual test data fitting. Salt spray concentration feedback adjustment: in, To control and adjust the flow output of the spray pump; This refers to the deviation in salt spray concentration. , , The proportional, integral, and derivative gain coefficients for salt spray feedback regulation; Temperature feedback adjustment: in, To control and regulate the temperature settings; To set the temperature; This is the measured temperature; , , For temperature feedback adjustment, the proportional, integral, and derivative gain coefficients are used. Humidity feedback adjustment: in, To control and regulate the output of humidity; To set the humidity; This is the actual measured humidity. , , The humidity feedback adjustment ratio, integral, and derivative gain coefficients.

7. The method for testing the imaging quality of a vehicle-mounted camera under high and low temperature salt spray environments according to claim 6, characterized in that: The S4 also incorporates a bidirectional airflow recovery mechanism, which provides a return channel for clean airflow to be collected, dehydrated, and reused, and is equipped with a salt trap.

8. A testing device for the imaging quality of a vehicle-mounted camera under high and low temperature salt spray conditions, employing the testing method described in any one of claims 1-7, characterized in that, Including environmental simulation systems: A darkroom provides a testing environment free from external light interference; Humidity generating chamber, used to generate different humidity conditions; Temperature generating chambers are used to provide different temperature environments; Salt spray generator is used to generate salt spray environments of different concentrations. The salt spray environment chamber is connected to a humidity generator, a temperature generator, and a salt spray generator. The humidity generator is connected to the salt spray environment chamber via humidity inlet and outlet pipes to supply humidity conditions, the temperature generator is connected to the salt spray environment chamber via temperature inlet and outlet pipes to supply temperature conditions, and the salt spray generator is connected to the salt spray environment chamber via a salt spray generator to supply salt spray conditions, thus simulating the environment of salt spray, high and low temperatures, and humidity changes. The salt spray environment chamber is equipped with high and low temperature resistant transparent glass for observation. The chamber body is made of corrosion-resistant materials and has internal temperature and humidity sensors that can monitor and report environmental parameters in real time. The salt spray generator uses a salt spray spraying device installed circumferentially inside the salt spray environment chamber to evenly spray the salt solution generated inside the salt spray generation chamber into the chamber, simulating salt spray environments of different concentrations. The salt spray generator also uses laser particle size analyzers installed on opposite sides of the salt spray environment chamber to monitor the salt spray mass concentration and particle diameter distribution in the salt spray chamber in real time. Temperature control subsystem: By installing temperature sensors at the camera to be tested and at the outlet of the temperature inlet and outlet pipes, the temperature is monitored and adjusted to maintain the temperature environment inside the cabin and simulate various extreme temperature conditions. Humidity control subsystem: By installing humidity sensors at the camera to be tested and at the outlet of the humidity inlet and outlet pipes, the humidity control subsystem monitors, adjusts and maintains the humidity environment inside the chamber, and works together with the temperature control subsystem to simulate complex temperature and humidity conditions. An adjustable high-pressure jet module is used to enable the salt spray generator's salt spray device to spray salt spray at different angles and pressures, thus replicating the salt spray impact conditions during real road driving. A self-cleaning system for transparent glass is installed inside the salt spray environment chamber to prevent salt spray deposition. The self-cleaning system for transparent glass includes a composite airflow vortex cleaning subsystem and an electrostatic anti-fog coating. The closed-loop control system for environmental parameters integrates high-precision sensors to monitor the impact of cleaning operations on the environment inside the chamber in real time, and dynamically adjusts cleaning parameters through adaptive algorithms to ensure that environmental fluctuations are within the allowable range. The bidirectional airflow recovery mechanism collects and dehydrates the clean airflow through the return channel for reuse, and is equipped with a salt trap to prevent salt spray crystallization and diffusion.

9. The vehicle-mounted camera imaging quality testing device under salt spray high and low temperature environment according to claim 8, characterized in that, It also includes optical testing systems: The camera mounting adjustable platform is set up inside the salt spray environment chamber to install the camera under test and achieve multi-degree-of-freedom adjustment to ensure that the camera can be accurately aligned with the test chart. The multi-degree-of-freedom chart attitude adjustment system is set up in a darkroom box to adjust the position and angle of the test chart, simulating the shooting environment of the vehicle camera under different attitudes; The Tuka supplemental lighting source adjustment system is set up in a darkroom box to configure the test lighting environment and simulate all-weather lighting conditions, including different color temperatures, illuminance and spectral distributions; The camera lighting drive system connects to the camera outside the environmental chamber via a data cable, enabling remote lighting and shooting of the camera. It also receives the raw image data captured by the camera, performs analog-to-digital conversion, and transmits the data to the image analysis module through an interface.

10. The vehicle-mounted camera imaging quality testing device under salt spray high and low temperature environment according to claim 9, characterized in that, It also includes image acquisition and analysis systems: The image acquisition card receives image data captured by the camera and transmits it to the image analysis module; The image analysis module performs real-time analysis on the acquired images, calculates and outputs quantitative indicators of image quality, including resolution, distortion, chromatic aberration, and defocus curve.

Images