Vehicle automatic headlamp correction method and system and headlamp control system thereof

Abstract

The invention provides an automatic vehicle headlamp correction method which is characterized in that the on-off threshold value of an automatic headlamp is dynamically adjusted by detecting the film pasting state of a front windshield of a vehicle and the corresponding illumination intensity. The method comprises the following specific steps: firstly, checking whether a vehicle front windshield is coated with a film, and obtaining initial illumination intensity; secondly, obtaining the illumination intensity in the vehicle after film pasting; calculating a correction proportion according to the film pasting state, the initial illumination intensity and the film pasting illumination intensity; and finally, calculating a correction threshold value according to the proportion, updating an on-off threshold value of the automatic headlight, and setting a hysteresis space to reduce the problem of frequent on-off of the automatic headlight when the illumination intensity jumps near the on-off threshold value. According to the method, the illumination intensity threshold value is accurately corrected, the problem that the automatic headlight is turned on and off abnormally after the vehicle is pasted with the film is effectively solved, and the driving safety and the energy utilization efficiency are remarkably improved.

Description

Technical Field

[0001] The present invention relates to an automotive intelligent driving assistance system, and particularly to a method and system for automatically calibrating vehicle headlights and its headlight control system. Background Art

[0002] In the field of automobiles, existing automatic headlight technologies mainly sense the external light intensity through an ambient light sensor and automatically control the turning on and off of the headlights according to a preset threshold. The automatic headlight on / off threshold set before the vehicle leaves the factory will be calibrated through various environments, and finally the threshold size is determined to ensure the most suitable for the driver's needs, that is, it cannot turn on the lights too early and waste energy, nor can it turn on the lights too late and affect driving safety. However, after the vehicle leaves the factory, most users will choose to apply a film to the front windshield of the vehicle to protect the vehicle glass. However, the ambient light sensor is generally set inside the cab, and the external ambient light needs to pass through the windshield to be sensed by the ambient light sensor. If a film is applied to the front windshield, the ambient light entering the cab from the outside is not only weakened by the windshield, but also weakened by the film applied to the windshield, resulting in a part of the ambient light actually received by the ambient light sensor being missing. In the same environment, obviously the ambient light intensity received when the front windshield is not filmed is higher. Therefore, filming the vehicle windshield will affect the response of the light intensity sensor to the true light intensity outside the vehicle, and thus will cause abnormal turning on and off of the vehicle headlights. Since the light intensity calibration of the vehicle is completed when it leaves the factory, a new method is needed to calibrate the automatic headlight on / off threshold of the vehicle after the windshield of the factory-produced vehicle is filmed. Summary of the Invention

[0003] In view of the above-mentioned disadvantages of the prior art, the purpose of the present invention is to provide a method and system for automatically calibrating vehicle headlights and its headlight control system, which are used to solve the problem that the front windshield film of the vehicle in the prior art affects the recognition accuracy of the vehicle for the light intensity, and further causes abnormal turning on and off of the vehicle automatic headlights.

[0004] To achieve the above object and other related objects, the present invention provides a method and system for automatically calibrating vehicle headlights and its headlight control system, which are applied to an automotive intelligent driving assistance system, check the film application status of the vehicle front windshield, and obtain the initial light intensity; obtain the film light intensity inside the vehicle after filming; calculate a calibration ratio according to the film application status, the initial light intensity, and the film light intensity; calculate a calibration threshold based on the calibration ratio and use it to update the on / off threshold of the automatic headlights.

[0005] In an embodiment of the present invention, the step of checking the film application status of the vehicle front windshield and obtaining the initial light intensity includes: checking the film application status of the vehicle front windshield; when the film application status is the non-filmed state, obtain the light intensity inside the vehicle as the initial light intensity.

[0006] In an embodiment of the present invention, the steps of checking the film pasting state of the vehicle front windshield and obtaining the initial light intensity include: checking the film pasting state of the vehicle front windshield; when the film pasting state is the film pasting state, obtaining the light intensity outside the vehicle as the initial light intensity.

[0007] In an embodiment of the present invention, when the film pasting state is the non-film pasting state, the correction ratio is calculated according to the following formula: Where α is the correction ratio, P1 is the initial light intensity, and P2 is the film pasting light intensity.

[0008] In an embodiment of the present invention, when the film pasting state is the non-film pasting state, the correction ratio is calculated according to the following formula: Where α is the correction ratio, P1 is the initial light intensity, P2 is the film pasting light intensity, and δ is the light transmittance of the vehicle front windshield.

[0009] In an embodiment of the present invention, the correction threshold is calculated according to the following formula based on the correction ratio: U' = U×(1 - λ); where U' is the correction threshold, U is the factory opening and closing threshold of the vehicle's automatic headlight, and λ is the correction ratio.

[0010] In an embodiment of the present invention, the steps of checking the film pasting state of the vehicle front windshield and obtaining the initial light intensity include: detecting the light intensity inside the vehicle: when the light intensity inside the vehicle is less than the preset light intensity threshold, the correction is stopped; when the light intensity inside the vehicle is greater than or equal to the light intensity threshold, the film pasting state of the vehicle front windshield is checked and the initial light intensity is obtained.

[0011] The present invention also provides a vehicle automatic headlight correction system, including: a state light intensity detection module for checking the film pasting state of the vehicle front windshield and obtaining the initial light intensity; an in-vehicle light intensity acquisition module for obtaining the film pasting light intensity inside the vehicle after film pasting; a calculation module for calculating a correction ratio according to the film pasting state, the initial light intensity, and the film pasting light intensity; and a threshold calculation and update module for calculating a correction threshold based on the correction ratio and updating the opening and closing threshold of the automatic headlight with it.

[0012] The present invention also provides an automatic headlight control system, comprising: an information host unit for obtaining the film pasting state of the vehicle front windshield and the initial light intensity in the case of the film pasted state; a light intensity acquisition unit for obtaining the initial light intensity when the vehicle is in the non-film pasted state, the film pasted light intensity and the real-time light intensity; a central domain control unit for calculating a correction threshold according to the film pasting state, the initial light intensity and the film pasted light intensity, and updating the correction threshold to the opening and closing threshold of the automatic headlight; the central domain control unit is further configured to send a headlight activation signal or a headlight extinguishing signal within a preset time according to the opening and closing threshold, a preset opening and closing range and the real-time light intensity; a headlight automatic control unit for automatically controlling the headlight according to the headlight activation signal or the headlight extinguishing signal.

[0013] In an embodiment of the present invention, the central domain control unit sends a headlight activation signal within a preset first time t1 when W < U - ΔI; wherein: when W < U - 2ΔI, a headlight activation signal is sent within a preset second time t2; when W < U + ΔI, a headlight activation signal is sent within a preset third time t3; wherein, W is the real-time light intensity; U is the opening and closing threshold; ΔI is a preset opening and closing range; and t2 < t1, t3 > t1.

[0014] As described above, a vehicle automatic headlight correction method, system and its headlight control system of the present invention have the following beneficial effects: corresponding light intensity detection methods are provided respectively according to the film pasting state of the vehicle front windshield. When the vehicle is not film pasted, since the influence of the glass on the light transmittance can be ignored, it is only necessary to measure the light intensity value inside the vehicle before film pasting as the initial light intensity and the light intensity value inside the vehicle after film pasting as the film pasted light intensity, and calculate the correction ratio according to the formula before film pasting; when the vehicle has been film pasted, the light intensity outside the vehicle is measured as the initial light intensity, and the light intensity inside the vehicle is measured as the film pasted light intensity, and the correction ratio after film pasting is calculated according to the formula after film pasting. According to the correction ratios obtained by the above two methods, a correction threshold is calculated by using the correction threshold formula and updated to the factory opening and closing threshold of the vehicle, so as to realize a correction method for correcting the opening and closing threshold of the automatic headlight in a relatively simple way after the vehicle leaves the factory; at the same time, in order to further make the opening and closing threshold more suitable for the actual situation, the present invention sets a hysteresis space on the updated opening and closing threshold to avoid the abnormal problem that the automatic headlight frequently opens and closes when the vehicle is driving in an environment where the light intensity is near the opening and closing threshold, further improving the correction value, realizing both energy saving and high efficiency and the improvement of user experience while ensuring driving safety, and significantly improving the performance and reliability of the automatic headlight system. Description of the Drawings

[0015] Figure 1 It is a schematic flow chart of the vehicle automatic headlight correction method provided by the embodiment of the present invention;

[0016] Figure 2 It shows a structural block diagram of a vehicle automatic headlight calibration system provided by an embodiment of the present invention;

[0017] Figure 3 It shows a structural block diagram of an automatic headlight control system provided by an embodiment of the present invention; Detailed implementation manners

[0018] The following uses specific specific examples to illustrate the implementation manners of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific implementation manners. Various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that, without conflict, the following embodiments and the features in the embodiments can be combined with each other.

[0019] It should be noted that the diagrams provided in the following embodiments only illustrate the basic concept of the present invention in a schematic manner. Therefore, only the components related to the present invention are shown in the diagrams, rather than being drawn according to the number, shape, and size of the components in actual implementation. The type, quantity, and ratio of each component in actual implementation can be arbitrarily changed, and the component layout type may also be more complex.

[0020] In the following description, a large number of details are explored to provide a more thorough explanation of the embodiments of the present invention. However, it is obvious to those skilled in the art that the embodiments of the present invention can be implemented without these specific details. In other embodiments, well-known structures and devices are shown in the form of block diagrams rather than in detail to avoid making the embodiments of the present invention difficult to understand.

[0021] The present invention provides a vehicle automatic headlight calibration method, system, and its headlight control system. For vehicle driving intelligent assistance, different calibration methods are adopted before and after pasting a film on the vehicle front windshield to adjust the light intensity threshold of the automatic headlight. According to different film pasting states of the vehicle, the pre-film calibration method can complete the threshold calibration through simple operations before pasting the film; while the post-film calibration method requires measuring the light intensity outside the vehicle for calibration. After correction and update, it can prevent the headlight from being abnormally lit and turned off when the light intensity frequently jumps, thereby optimizing the control performance of the automatic headlight and improving driving safety and energy efficiency.

[0022] Please refer to Figure 1 , which shows a schematic flow diagram of the vehicle automatic headlight calibration method in an exemplary embodiment of the present application, including the following steps:

[0023] S1, checking the film status of the front windshield of the vehicle and obtaining the initial light intensity;

[0024] The film state of the front windshield of the vehicle will affect its original light transmittance. Therefore, the present invention provides two correction methods for vehicles that have not been filmed but are ready to be filmed and vehicles that have already been filmed. At the same time, the requirement for the light measurement environment is that the vehicle should be in outdoor natural light conditions with good light.

[0025] Specifically, in one embodiment of the present invention, the steps of checking the film state of the front windshield of the vehicle and obtaining the initial light intensity include:

[0026] First, check the film status of the vehicle's front windshield;

[0027] According to whether the vehicle has been filmed, it is confirmed whether the vehicle is in a film-painted state or a non-film-painted state.

[0028] Secondly, when the film-applying state is the un-film-applying state, the light intensity inside the vehicle is obtained as the initial light intensity.

[0029] When the film state of the vehicle is the unfilmed state, the light intensity value at the front windshield inside the vehicle is obtained as the initial light intensity. In a preferred embodiment of the present invention, the light intensity inside the vehicle is measured by a light intensity sensor provided at the front windshield of the vehicle, such as conventional light intensity testing equipment: a light meter, a spectroradiometer, a photoresistor sensor, and those skilled in the art may select any other light intensity measuring equipment to obtain the light intensity.

[0030] Then, when the film-applying state is the film-applying state, the light intensity outside the vehicle is acquired as the initial light intensity.

[0031] When the film-applied state of the vehicle is the film-applied state, the light intensity value at the front windshield outside the vehicle is obtained as the initial light intensity. In a preferred embodiment of the present invention, the light intensity value outside the vehicle is obtained by measuring with a light intensity measuring device, and those skilled in the art may obtain it with other light measuring devices of their choice.

[0032] S2, obtaining the light intensity of the film inside the car after the film is applied;

[0033] The calibration process requires obtaining the light transmittance of the windshield before and after film application, so the initial light intensity and the film light intensity need to be measured separately.

[0034] When the vehicle is in the unfilmed state, the effect of the glass transmittance on the light intensity can be ignored, so the light intensity inside the vehicle when the vehicle is not filmed can be used as the initial light intensity. However, after the film is applied, the light transmittance of the windshield will change, so it is necessary to measure the film light intensity inside the vehicle again.

[0035] When the vehicle is in the film - applied state, the light outside the vehicle has been obtained as the initial light intensity. Therefore, it is also necessary to measure the light intensity of the film - applied light inside the vehicle.

[0036] S3. Calculate a correction ratio according to the film - applied state, the initial light intensity, and the film - applied light intensity.

[0037] Specifically, in an embodiment of the present invention, based on different film - applied states of the vehicle, the present invention provides two correction - ratio calculation formulas.

[0038] First, when the film - applied state is the non - film - applied state, the correction ratio is calculated according to the following formula: where α is the correction ratio, P1 is the initial light intensity, and P2 is the film - applied light intensity.

[0039] Second, when the film - applied state is the film - applied state, the correction ratio is calculated according to the following formula: where α is the correction ratio, P1 is the initial light intensity, P2 is the film - applied light intensity, and δ is the light transmittance of the vehicle's front windshield.

[0040] S4. Calculate a correction threshold based on the correction ratio and use it to update the opening and closing threshold of the automatic headlight.

[0041] Specifically, in an embodiment of the present invention, the correction threshold is calculated according to the following formula based on the correction ratio: U' = U×(1 - λ); where U' is the correction threshold, U is the factory - set opening and closing threshold of the vehicle's automatic headlight, and λ is the correction ratio.

[0042] Replace the factory - set opening and closing threshold U of the vehicle's automatic headlight before leaving the factory with the correction threshold U' to achieve the update of the opening and closing threshold.

[0043] Specifically, in an embodiment of the present invention, the steps of checking the film - applied state of the vehicle's front windshield and obtaining the initial light intensity include:

[0044] First, detect the light intensity inside the vehicle and determine whether the correction condition is met according to the light - intensity value inside the vehicle.

[0045] The purpose of calibrating the automatic headlight on / off threshold is to enable the reaction effect of the headlights to be as close as possible to the effect achieved by the on / off threshold set before leaving the factory during the normal use of the vehicle after leaving the factory. Therefore, the natural light environment conditions of the vehicle during the calibration operation should be as similar as possible to the lighting conditions during the natural use of the vehicle. Further, during the day in an environment with good lighting conditions, there is no need to turn on the automatic headlights. At other times, as long as the lighting conditions of the environment are good, there is also no need to turn on the automatic headlights. In other environments with poor lighting conditions, the automatic headlights need to be turned on. Therefore, to achieve this purpose, a light intensity threshold is set before the vehicle leaves the factory to determine whether the vehicle is in an environment with good lighting conditions. In a preferred embodiment of the present invention, the best calibration environment is selected when the natural light source is good, that is, when the sunlight is sufficient.

[0046] Secondly, when the light intensity inside the vehicle is less than the preset light intensity threshold, it indicates that the environment where the vehicle is located does not meet the calibration conditions, and the calibration is stopped;

[0047] When the light intensity inside the vehicle is less than the preset light intensity threshold, if it is not in an environment with good lighting conditions, the obtained calibration result is an invalid result. Therefore, in a preferred embodiment of the present invention, when the user starts the calibration operation in an environment where the light intensity is less than the preset light intensity threshold, the user is reminded through sound and light signals that the environment where the vehicle is located is not suitable for calibrating the automatic headlight on / off threshold, and the vehicle should be driven to an environment with good lighting conditions and tried again.

[0048] At the same time, when the light intensity inside the vehicle is greater than or equal to the light intensity threshold, the film pasting state of the vehicle's front windshield is checked, and the initial light intensity is obtained based on the film pasting state of the vehicle's front windshield.

[0049] When the lighting environment where the vehicle is located meets the calibration requirements, that is, when the light intensity value inside the vehicle is greater than or equal to the light intensity threshold, the calibration can be carried out according to the invention method. Check the film pasting state of the vehicle's front windshield, obtain the initial light intensity according to the film pasting state of the vehicle's front windshield, and perform the next calibration operation.

[0050] Please refer to Figure 2, which shows that the present invention discloses a vehicle automatic headlight correction system 200, including: a status light intensity detection module 210, an in-vehicle light intensity acquisition module 220, a calculation module 230, and a threshold calculation and update module 240. Among them, the status light intensity detection module 210 is used to check the film pasting status of the vehicle front windshield and obtain the initial light intensity; the in-vehicle light intensity acquisition module 220 is used to obtain the film-pasting light intensity inside the vehicle after film pasting; the calculation module 230 is used to calculate the correction ratio according to the film pasting status, the initial light intensity and the film-pasting light intensity; the threshold calculation and update module 240 is used to calculate a correction threshold based on the correction ratio and update the opening and closing threshold of the automatic headlight with it.

[0051] For the specific limitations of the vehicle automatic headlight correction system, reference can be made to the limitations on the vehicle automatic headlight correction method in the above text, which will not be elaborated here. Each module in the above battery detection system can be implemented in whole or in part by software, hardware and their combination.

[0052] The above modules can be embedded in the processor of the computer device in hardware format or independent of it, or stored in the memory of the computer device in software format, so as to facilitate the processor to call the corresponding operations of the above modules.

[0053] It should be noted that in order to highlight the innovative part of the present invention, modules that are not closely related to solving the technical problems proposed by the present invention are not introduced in this embodiment, but this does not mean that there are no other modules in this embodiment.

[0054] Please refer to Figure 3 , the present invention also discloses a vehicle automatic headlight correction system 300, including: an information host unit 310, a light intensity acquisition unit 320, a central domain control unit 330, and a headlight automatic control unit 340. Among them, the information host unit 310 is used to obtain the film pasting status of the vehicle front windshield and the initial light intensity in the case of the film pasting state; the light intensity acquisition unit 320 is used to obtain the initial light intensity, the film-pasting light intensity and the real-time light intensity when the vehicle is in the non-film-pasting state; the central domain control unit 330 is used to calculate a correction threshold according to the film pasting status, the initial light intensity and the film-pasting light intensity, and update the correction threshold as the opening and closing threshold of the automatic headlight; the central domain control unit is also used to issue a headlight activation signal or a headlight extinguishing signal within a preset time according to the opening and closing threshold, a preset opening and closing range and the real-time light intensity; the headlight automatic control unit 340 is used to automatically control the headlight according to the opening and closing threshold.

[0055] Specifically, in an embodiment of the present invention, when W < U - ΔI, the central domain control unit sends a headlight activation signal within a preset first time t1; where: when W < U - 2ΔI, it sends a headlight activation signal within a preset second time t2; when W < U + ΔI, it sends a headlight activation signal within a preset third time t3; where W is the real-time light intensity; U is the opening and closing threshold; ΔI is the preset opening and closing range; and t2 < t1, t3 > t1.

[0056] In a preferred embodiment of the present invention, the information host unit 310 can be established on the basis of a touch screen. When the user starts threshold calibration, click the calibration request button on the information host unit 310. The information host unit 310 pops up calibration guidance information and a confirmation button for whether to apply a film. When the user clicks the "Yes" button, the information host unit 310 obtains information to realize the acquisition of the vehicle film application state. When the vehicle is in the film-applied state, the information host unit 310 pops up an input box for entering the external light intensity of the vehicle. The user enters the measured external light intensity value of the vehicle in the input box and clicks the OK button. The information host unit 310 obtains the input information to realize the initial light intensity when the vehicle film application state is the film-applied state.

[0057] Specifically, in a preferred embodiment of the present invention, the light intensity acquisition unit 320 selects the light intensity sensor provided at the front windshield of the vehicle as the hardware basis. Those skilled in the art can select other light intensity detection devices to achieve the same function.

[0058] Specifically, in a preferred embodiment of the present invention, the central domain control unit 330 uses the central domain control module of the vehicle as the hardware basis and is electrically connected to the information host unit 310, the light intensity acquisition unit 320, and the headlight automatic control unit 340. Further, the present invention provides the specific process of the vehicle automatic headlight opening and closing threshold as follows:

[0059] The user clicks the calibration button displayed on the information host unit 310. The information host unit 310 sends a calibration request signal to the central domain control unit 330. The central domain control unit 330 receives and obtains the light intensity inside the vehicle through the light intensity acquisition unit 320, records the obtained light intensity inside the vehicle, and determines whether the light intensity P1 inside the vehicle is less than the preset light intensity threshold of the vehicle. If so, the central domain control unit 330 feeds back a signal that cannot be calibrated to the information host unit 310. The information host unit receives and displays "The lighting environment where the vehicle is located is not suitable for calibration operation. Please try again in the daytime and in a place with good ambient lighting." If the light intensity inside the vehicle is higher than the preset light intensity threshold, it sends a signal that can be calibrated to the information host unit 310. The information host unit 310 receives and pops up an option of "Is the current windshield already film-applied?" At this time, there are two steps according to the user's selection:

[0060] (1) If the user selects "Yes", the information host unit 310 pops up a prompt message "Please place the tool for measuring the ambient light intensity of the environment in front of the windshield outside the vehicle to measure the light intensity", and pops up a light intensity input box. The user inputs the measured light intensity at the front windshield outside the vehicle, clicks the OK button. The information host unit 310 receives the "Yes" signal, pops up the light intensity input box, and displays the words "Please place the tool for measuring the ambient light intensity of the environment in front of the windshield outside the vehicle and input the light intensity into the input box". After the user inputs the light intensity value, the information host unit 310 receives the light intensity value, and sends the signal that the vehicle is in the film - applied state and the received light intensity value to the central domain control unit 330. The central domain control unit 330 receives and uses the received light intensity value as the initial light intensity, and uses the light intensity as the light intensity of the film - applied interior of the vehicle. It judges whether the film - applied light intensity is less than the initial light intensity. If not, the central domain control unit 330 sends a signal of non - meeting the calibration requirement to the information host unit 310, and the host unit 310 receives and pops up a prompt message "Input error or the light environment where the vehicle is located is not suitable for calibration operation. Please try again in a place with good daylight and good ambient light"; if so, the central domain control unit 330 determines the calibration ratio according to the initial light intensity and the film - applied light intensity, determines the calibration threshold according to the calibration ratio, and replaces the factory opening and closing threshold of the vehicle's automatic headlight with the calibration threshold, that is, realizes the calibration process of the automatic headlight opening and closing threshold when the vehicle is in the film - applied state.

[0061] (2) If the user selects "No", the information host unit 310 pops up the words "Please apply film" and pops up an option "Is the film application completed?". After the user completes the film application and clicks the "Completed" option, the information host unit 310 receives and sends a signal that the vehicle is in the non - film - applied state to the central domain control unit 330. The central domain control unit 330 receives and uses the saved light intensity as the initial light intensity, measures the light intensity value of the interior of the vehicle after film application again through the light intensity acquisition unit 320 as the film - applied light intensity, and judges whether the film - applied light intensity is less than the initial light intensity. If not, the central domain control unit 330 sends a signal of non - meeting the calibration requirement to the information host unit 310, and the information host unit 310 receives and pops up a prompt message "Input error or the light environment where the vehicle is located is not suitable for calibration operation. Please try again in a place with good daylight and good ambient light"; if so, the central domain control unit 330 determines the calibration ratio according to the initial light intensity and the film - applied light intensity, determines the calibration threshold according to the calibration ratio, and replaces the factory opening and closing threshold of the vehicle's automatic headlight with the calibration threshold, that is, realizes the calibration process of the automatic headlight opening and closing threshold when the vehicle is in the non - film - applied state.

[0062] It should be noted that for the data filling and option button clicking described in the embodiments, after the information host unit 310 pops up the information or button, a timing request is sent to the central domain control unit 330. The user needs to complete it within the corresponding preset time. If the operation times out, the central domain control unit 330 sends a timeout signal to the information host unit 310, and the information host unit 310 receives and pops up an information prompt of "Operation timed out, please retry".

[0063] Furthermore, when the vehicle is driving normally in a tree-lined road or other lighting environments where the light intensity frequently jumps, it will trigger the frequent lighting and turning off of the vehicle's automatic headlights. To solve this problem, the present invention further provides corresponding solutions as follows:

[0064] When the central domain control unit 330 receives that the light intensity sent by the light intensity acquisition unit 320 is less than U - ΔI, the central domain control unit 330 sends an automatic headlight activation signal to the automatic headlight control unit 340, and the headlights turn on, where U is the automatic headlight on / off threshold and ΔI is the preset range; when the central domain control unit 330 receives that the light intensity sent by the light intensity acquisition unit 320 is greater than U + ΔI, the central domain control unit 330 sends an extinguishing signal to the automatic headlight control unit 340, and the automatic headlights turn off. This method prevents the problem of low beam flickering when the ambient light intensity frequently jumps near the on / off threshold by reserving a hysteresis space.

[0065] In another preferred embodiment of the present invention, when the central domain control unit 330 receives that the light intensity value sent by the light intensity acquisition unit 320 jumps from W to less than U - ΔI (W > U - ΔI), it is required that the central domain control unit 330 send an activation signal to the automatic headlight control unit 340 within the first preset time period, where W is the real-time light intensity value obtained and sent by the light intensity acquisition unit 320, U is the automatic headlight on / off threshold, and ΔI is the preset range. When the central domain control unit 330 receives that the light intensity value sent by the light intensity acquisition unit 320 jumps from W to less than U - 2ΔI (W < U - 2ΔI), it is required that the central domain control unit 330 send an activation signal to the automatic headlight control unit 340 within the second preset time period, where the second preset time period is less than the first preset time period. When the light intensity value sent by the light intensity acquisition unit 320 jumps from W to greater than U + ΔI, it is required that the central domain control unit 330 send an extinguishing signal to the automatic headlight control unit 340 within the third preset time period, where the third preset time period is greater than the first preset time period.

[0066] In summary, a vehicle automatic headlight calibration method, system and its headlight control system disclosed by the present invention can solve the problem that it is difficult to calibrate the change of the light intensity threshold caused by vehicle film pasting after the vehicle leaves the factory. At the same time, in an environment where the light intensity jumps near the opening and closing thresholds in reality, the automatic headlights will frequently open and close. A hysteresis space is set to achieve more appropriate opening and closing of the headlights, and at the same time, the service life of the automatic headlights can be effectively improved. It has the beneficial effects of a simple and effective method and easy promotion. Therefore, the present invention effectively overcomes various shortcomings in the prior art and has high industrial utilization value.

[0067] The above embodiments are only illustrative of the principles and effects of the present invention, and are not used to limit the present invention. Any person familiar with this technology can modify or change the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or changes completed by those with ordinary knowledge in the technical field without departing from the spirit and technical idea disclosed by the present invention should still be covered by the claims of the present invention.

Claims

1. A vehicle automatic headlight calibration method, characterized in that: The method comprises: Check the film status of the vehicle's front windshield and obtain the initial light intensity; Get the light intensity of the film inside the car after the film is applied; A correction ratio is calculated according to the film state, the initial light intensity and the film light intensity; a correction threshold is calculated according to the correction ratio and used to update the on / off threshold of the automatic headlights.

2. The vehicle automatic headlight calibration method according to claim 1, characterized in that: The steps of checking the film state of the front windshield of the vehicle and obtaining the initial light intensity include: Check the film status of the vehicle's front windshield; When the film-applying state is the un-film-applying state, the light intensity inside the vehicle is obtained as the initial light intensity.

3. The vehicle automatic headlight calibration method according to claim 1, characterized in that: The steps of checking the film state of the front windshield of the vehicle and obtaining the initial light intensity include: Check the film status of the vehicle's front windshield; When the film-applying state is the film-applying state, the light intensity outside the vehicle is acquired as the initial light intensity.

4. The vehicle automatic headlight calibration method according to claim 1, characterized in that: When the film-attaching state is the unattached state, the correction ratio is calculated according to the following formula: Wherein, α is the correction ratio, P1 is the initial light intensity, and P2 is the film light intensity.

5. The vehicle automatic headlight calibration method according to claim 1, characterized in that: When the film sticking state is the film sticking state, the correction ratio is calculated according to the following formula: Wherein, α is the correction ratio, P1 is the initial light intensity, P2 is the light intensity of the film, and δ is the light transmittance of the front windshield of the vehicle.

6. The vehicle automatic headlight calibration method according to claim 1, characterized in that: The correction threshold is calculated according to the correction ratio according to the following formula: U'=U×(1-λ); wherein U' is the correction threshold, U is the factory on / off threshold of the vehicle automatic headlights, and λ is the correction ratio.

7. The vehicle automatic headlight calibration method according to claim 1, characterized in that: The step of checking the film state of the front windshield of the vehicle and obtaining the initial light intensity includes: Detecting the light intensity inside the car: When the light intensity in the vehicle is less than a preset light intensity threshold, the correction is stopped; When the light intensity in the vehicle is greater than or equal to the light intensity threshold, the film state of the vehicle's front windshield is checked and the initial light intensity is obtained.

8. A vehicle automatic headlight calibration system, characterized in that: The system comprises: The state light intensity detection module checks the film status of the vehicle's front windshield and obtains the initial light intensity; The light intensity acquisition module in the car obtains the light intensity of the film in the car after the film is applied; A calculation module, used for calculating a correction ratio according to the film sticking state, the initial light intensity and the film sticking light intensity; The threshold calculation and updating module is used to calculate the correction threshold according to the correction ratio, and use it to update the on / off threshold of the automatic headlights.

9. An automatic headlight control system, characterized in that: The system comprises: An information host unit is used to obtain the film-applied state of the front windshield of the vehicle and the initial light intensity when the film is applied; A light intensity acquisition unit is used to obtain the initial light intensity of the vehicle without film, the light intensity after film application, and the real-time light intensity; The central domain control unit is used to calculate a correction threshold according to the film state, the initial light intensity and the film light intensity, and update the correction threshold to the automatic headlight on / off threshold; the central domain control unit is also used to send a headlight activation signal or a headlight off signal within a preset time according to the on / off threshold, the preset on / off range and the real-time light intensity; The headlight automatic control unit is used to automatically control the headlight according to the headlight activation signal or the headlight off signal.

10. The automatic headlight control system according to claim 9, characterized in that: When W < U - ΔI, the central domain control unit sends a headlight activation signal within a preset first time t1; where: When W < U - 2ΔI, it sends a headlight activation signal within a preset second time t2; When W < U + ΔI, it sends a headlight activation signal within a preset third time t3; where, W is the real-time light intensity; U is the opening and closing threshold; ΔI is the preset opening and closing range; and t2 < t1, t3 > t1.

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