High beam and low beam height calibration method and system

Abstract

This invention provides a method and system for calibrating the height of the light-dark line of a low beam lamp. The method involves adjusting the light source to a first height; adjusting the height of an illuminance meter until its first reading reaches a first critical value, and recording the second height corresponding to the first critical value; acquiring the illuminance of the light source using an optical axis height measuring instrument; obtaining a second reading of the illuminance from the optical axis height measuring instrument, and recording the third height corresponding to the second critical value; calculating the measurement error based on the second and third heights; and calculating the calibration height based on the measurement error. This invention uses a light source instead of a low beam lamp for detection, and an adjustable illuminance meter to determine the height of the light-dark line. The height of the light source during testing is detected using an optical axis height measuring instrument, and the measurement error is calculated based on the results of the two tests, thus achieving the calibration function.

Description

Technical Field

[0001] This invention relates to the field of automobile manufacturing technology, and in particular to a method and system for calibrating the height of the low beam headlight's light and dark lines. Background Technology

[0002] During the production process, before a vehicle leaves the factory, the position of the low beam headlight's cutoff line (or the angle of the low beam's optical axis deflection) needs to be adjusted to meet regulatory requirements. Therefore, the position of the low beam headlight's cutoff line needs to be tested.

[0003] The current testing method involves using a single vehicle as a standard vehicle. The position of the light and dark lines on this standard vehicle is adjusted on a standard workbench until they fall within the regulatory midpoint. This standard vehicle is then used to calibrate the light and dark line height detection equipment on the production line. Subsequent vehicles leaving the factory are then adjusted to use this height as a reference for adjusting the optical axis position.

[0004] Current technology for measuring the position of the light and dark lines on a standard vehicle involves shining the low beam headlights onto a screen and measuring the height of the light and dark lines on the screen using a ruler. This testing method is prone to visual bias; furthermore, the height of the standard vehicle can change as it moves to the production line, leading to measurement errors; and during calibration on the production line, the instrument's detection algorithm can also have biases. Therefore, due to these factors, the accuracy of low beam headlight axis height calibration and measurement is poor. Vehicles that use this standard to adjust the headlight axis height are prone to failing to meet regulatory requirements. Summary of the Invention

[0005] The main objective of this invention is to provide a method and system for calibrating the height of the low beam headlight's light and dark lines. This aims to solve the technical problem in the prior art where measurement errors lead to low accuracy in the measurement results during the calibration and testing of the low beam headlight axis of a vehicle, resulting in the vehicle failing to meet regulatory requirements.

[0006] To achieve the above objectives, this invention proposes a method for calibrating the height of the low beam headlight's light and dark line, the method comprising:

[0007] Adjust the light source to the first height;

[0008] An illuminance meter is installed, and the distance between the illuminance meter and the light source is a preset length;

[0009] The illuminance of the light source is collected by the illuminance meter.

[0010] Adjust the height of the illuminance meter until the first reading of the illuminance meter reaches the first critical value, and record the second height corresponding to the first reading value being the first critical value;

[0011] Set up an optical axis height measuring instrument, and make the distance between the optical axis height measuring instrument and the light source the preset length;

[0012] The illuminance of the light source is collected using the optical axis height measuring instrument.

[0013] Obtain the second reading of the illuminance on the optical axis height measuring instrument, and record the third height corresponding to the second reading value being the second critical value;

[0014] The measurement error is calculated based on the second height and the third height;

[0015] The calibration height is calculated based on the measurement error.

[0016] Optionally, the step of adjusting the height of the illuminance meter until the first reading of the illuminance meter reaches a first critical value, and recording the second height corresponding to the first reading value being the first critical value, includes:

[0017] Move the illuminance meter from bottom to top and obtain the first reading of the illuminance meter;

[0018] When the first reading value changes from the first preset value to the second preset value, the first preset value before it becomes the second preset value is taken as the first threshold value;

[0019] Record the second height corresponding to the first reading value when the first threshold value is reached.

[0020] Optionally, the step of setting an optical axis height measuring instrument and ensuring that the distance between the optical axis height measuring instrument and the light source is the preset length includes:

[0021] Move the light source to the area to be measured;

[0022] The optical axis height measuring instrument is set in the area to be measured, and the distance between the optical axis height measuring instrument and the light source is the preset length.

[0023] Optionally, after adjusting the light source to the first height, the method further includes:

[0024] Adjust the optical axis of the light source to be horizontal;

[0025] After the step of moving the light source to the area to be measured, the method further includes:

[0026] The optical axis of the light source is readjusted to be horizontal.

[0027] Optionally, the step of collecting the illuminance of the light source using the illuminance meter includes:

[0028] Adjust the light source and the illuminance meter to be on the same straight line;

[0029] Adjust the detection surface of the illuminance meter so that the detection surface of the illuminance meter is perpendicular to the optical axis of the light source;

[0030] Turn on the light source and illuminate the detection surface of the illuminance meter to collect the illuminance of the light source through the illuminance meter.

[0031] Optionally, the step of acquiring the illuminance of the light source using the optical axis height measuring instrument includes:

[0032] Adjust the light source and the optical axis height measuring instrument to be on the same straight line;

[0033] Adjust the detection surface of the optical axis height measuring instrument so that the detection surface of the optical axis height measuring instrument is perpendicular to the optical axis of the light source;

[0034] Turn on the light source and illuminate the detection surface of the optical axis height measuring instrument to collect the illuminance of the light source through the optical axis height measuring instrument.

[0035] Optionally, the second height H, the third height h, and the measurement error Δh satisfy the following relationship:

[0036] Hh = △h.

[0037] Optionally, the step of calculating the calibration height based on the measurement error includes:

[0038] Obtain the measured value from the optical axis height measuring instrument;

[0039] The calibrated height is calculated based on the measured value and the measurement error.

[0040] Optionally, the measured value h0, the measurement error Δh, and the calibration height C satisfy the following relationship:

[0041] C = h0 + Δh.

[0042] Furthermore, to address the aforementioned problems, this invention also proposes a low beam headlight brightness / darkness line height calibration system, which includes:

[0043] A gimbal, wherein a light source is provided on the gimbal, and the gimbal is used to adjust a first height of the light source;

[0044] An illuminance meter is used to collect the illuminance value of the light source and measure the second height of the light-dark line of the light source;

[0045] An optical axis height measuring instrument is used to collect the illuminance value of the light source and measure the third height of the light and dark line of the light source;

[0046] The calculation module is used to calculate the measurement error based on the second height and the third height, and to calculate the calibration height based on the measurement error.

[0047] This invention employs a light source instead of a low beam headlight for detection, avoiding low beam headlight height deviation caused by vehicle movement. It uses an adjustable illuminance meter to determine the height of the light source's light and dark lines based on the illuminance measured by the illuminance meter, eliminating optical axis height deviation caused by manual observation. During calibration, the height of the light source during testing is measured using an optical axis height measuring instrument. The measurement error is calculated based on the results of the two measurements. This allows for the calculation of the actual low beam headlight axis height of other vehicles during subsequent testing using the measurement error correction parameter, thus achieving the calibration function. Attached Figure Description

[0048] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0049] Figure 1 This is a flowchart illustrating the first embodiment of the low beam headlight brightness and darkness line calibration method of the present invention;

[0050] Figure 2 This is a flowchart illustrating the second embodiment of the low beam headlight brightness and darkness line calibration method of the present invention;

[0051] Figure 3 This is a flowchart illustrating the third embodiment of the low beam headlight brightness and darkness line calibration method of the present invention;

[0052] Figure 4 This is a flowchart illustrating the fourth embodiment of the low beam headlight brightness and darkness line calibration method of the present invention;

[0053] Figure 5 This is a flowchart illustrating the fifth embodiment of the low beam headlight brightness and darkness line calibration method of the present invention;

[0054] Figure 6 This is a flowchart illustrating the sixth embodiment of the low beam headlight brightness and darkness line calibration method of the present invention;

[0055] Figure 7 This is a schematic diagram of the low beam headlight brightness and darkness line calibration system of the present invention.

[0056] Explanation of icon numbers:

[0057] label name label name 10 light source 20 gimbal 30 Illuminance meter

[0058] The realization of the objective, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0059] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0060] It should be noted that all directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present invention are only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indication will also change accordingly.

[0061] Furthermore, in this invention, descriptions involving "first," "second," etc., are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0062] In this invention, unless otherwise explicitly specified and limited, the terms "connection," "fixed," etc., should be interpreted broadly. For example, "fixed" can mean a fixed connection, a detachable connection, or an integral part; it can mean a mechanical connection or an electrical connection; it can mean a direct connection or an indirect connection through an intermediate medium; it can mean the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0063] Furthermore, the technical solutions of the various embodiments of the present invention can be combined with each other, but only if they are feasible for those skilled in the art. If the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such combination of technical solutions does not exist and is not within the scope of protection claimed by the present invention.

[0064] This invention provides a method for calibrating the height of the light and dark lines of low beam headlights. Please refer to [the relevant documentation]. Figure 1 , Figure 1 This is a flowchart illustrating the first embodiment of the low beam headlight brightness and darkness line height calibration method of the present invention. The low beam headlight brightness and darkness line height calibration method includes the following steps:

[0065] Step S10: Adjust the light source 10 to the first height;

[0066] Step S20: Set up the illuminance meter 30 and make the distance between the illuminance meter 30 and the light source 10 a preset length;

[0067] Step S30: Collect the illuminance of the light source 10 using the illuminance meter 30;

[0068] Step S40: Adjust the height of the illuminance meter 30 until the first reading of the illuminance on the illuminance meter 30 reaches its maximum, and record the second height corresponding to the maximum first reading;

[0069] Step S50: Set the optical axis height measuring instrument and make the distance between the optical axis height measuring instrument and the light source 10 the preset length;

[0070] Step S60: Collect the illuminance of the light source 10 using the optical axis height measuring instrument;

[0071] Step S70: Obtain the second reading of the illuminance on the optical axis height measuring instrument, and record the third height corresponding to the maximum second reading;

[0072] Step S80: Calculate the measurement error based on the second height and the third height;

[0073] Step S90: Calculate the calibration height based on the measurement error.

[0074] In this embodiment, the light source 10 can be fixed on the gimbal 20, and the height of the light source 10 can be adjusted by the gimbal 20.

[0075] The first height is determined based on the vehicle model to be measured. For example, a standard vehicle is selected, and its tire pressure, number of occupants, fuel level, and other conditions are adjusted to ensure the standard vehicle is in normal operating condition for measurement, thereby improving detection accuracy. After adjustment, the distance from the center of the low beam headlight 10 of the standard vehicle to the ground is measured as the first height.

[0076] The light source 10 can be the same low beam headlight as that of a standard vehicle, and it is fixed on the gimbal 20. When adjusting the height of the light source 10, the distance from the center of the light source 10 to the ground surface is also used as the first height to ensure that the control variables are consistent.

[0077] After the initial height of the light source 10 is adjusted, the height of the light-dark line of the light source 10 should be measured in a standard environment, such as a laboratory environment free from other light interference, so that the measurement result is as close as possible to the actual height of the light-dark line of the light source 10. The distance between the light source 10 and the illuminance meter 30 should be adjusted to the preset length, which can be set between 10m and 15m, so that a clear light-dark line is visible when the beam of light from the light source 10 falls on the position of the illuminance meter 30.

[0078] It is understandable that areas above the light-dark line are either dark or have very low light intensity, while areas below the light-dark line have higher light intensity and are bright. Therefore, the difference in illuminance is greatest at the light-dark line.

[0079] The illuminance meter 30 includes a measuring head and a high-precision ruler, with the measuring head being adjustable in height on the high-precision ruler. When the light beam emitted by the light source 10 shines on the measuring head, the illuminance value of the light source 10 at that height position will be displayed on the measuring head.

[0080] By moving the measuring head up and down, when the measuring head moves from below the light-dark line to the critical position of the light-dark line, that is, just before the measuring head enters the dark height above the light-dark line, the first reading of the illuminance meter 30 is the first critical value. At this time, the height of the measuring head on the high-precision ruler is recorded as the second height.

[0081] After the second height measurement is completed, the illuminance meter 30 is replaced with an optical axis height measuring instrument.

[0082] The illuminance values ​​of the light source 10 at various locations are collected using the optical axis height measuring instrument. Similarly, at the position of the light-dark line, the collected illuminance value shows a sudden drop. Therefore, before entering the dark height just above the light-dark line, the second reading displayed on the optical axis height measuring instrument is the second critical value. At this time, the height of the optical axis height measuring instrument at the second critical value position is recorded as the third height.

[0083] The measurement error is calculated using the second height and the third height.

[0084] The second height H, the third height h, and the measurement error Δh satisfy the following formula:

[0085] Formula 1: Hh = △h.

[0086] During actual measurement, the headlights of the vehicle under test are shone onto the optical axis height measuring instrument. The height of the light and dark lines of the vehicle under test is measured by the optical axis height measuring instrument, and the calibration height of the vehicle under test is calculated by combining the measurement error. The calibration height is the actual height of the light and dark lines of the vehicle under test.

[0087] When the calibration height does not meet the regulatory requirements, the optical axis position of the low beam can be adjusted using a dimming screwdriver to make the light and dark lines meet the regulatory requirements.

[0088] The technical solution of this invention uses a light source 10 instead of a low beam headlight for detection, avoiding the low beam headlight height deviation caused by vehicle movement; and uses an adjustable illuminance meter 30 to determine the height of the light and dark line of the light source 10 by detecting the illuminance through the illuminance meter 30, eliminating the optical axis height deviation caused by manual visual inspection; during calibration, the height of the light source 10 during testing is detected by the optical axis height measuring instrument, and the measurement error is calculated based on the results of the two tests, so that in the subsequent testing of other vehicles, the actual height of the low beam headlight axis of other vehicles can be calculated by using the measurement error correction parameter, thus realizing the calibration function.

[0089] Further, please refer to Figure 2 , Figure 2 This is a flowchart illustrating the second embodiment of the low beam headlight brightness and darkness line calibration method of the present invention. Step S40 includes:

[0090] Step S41: Move the illuminance meter 30 from bottom to top and obtain the first reading of the illuminance meter 30;

[0091] Step S42: When the first reading value changes from the first preset value to the second preset value, the first preset value before it becomes the second preset value is taken as the first threshold value;

[0092] Step S43: Record the second height corresponding to the first reading value when the first reading value is the first critical value.

[0093] During actual measurement, the illuminance meter 30 is gradually moved from bottom to top. When the illuminance meter 30 is in the bright area below the light-dark line, the first reading is displayed as the first preset value, which can be set to 1000 lumens to 1400 lumens.

[0094] When the illuminance meter 30 is in a dark area above the light-dark line, the first reading value is displayed as the second preset value, which can be set to 0 to 1 lumen.

[0095] When the first reading value changes from the first preset value to the second preset value, the first preset value before it changes to the second preset value is taken as the first critical value, and the corresponding second height is recorded, thereby ensuring the accuracy of the measured second height.

[0096] Further, please refer to Figure 3 , Figure 3This is a flowchart illustrating the third embodiment of the low beam headlight brightness and darkness line calibration method of the present invention. Step S50 includes the following steps:

[0097] Step S51: Move the light source 10 to the area to be tested;

[0098] Step S52: Set the optical axis height measuring instrument in the area to be measured, and make the distance between the optical axis height measuring instrument and the light source 10 the preset length.

[0099] In this embodiment, when actually measuring the vehicle under test, the vehicle under test should be measured in the area to be measured.

[0100] Therefore, in order to ensure the accuracy of the measurement error calculation, when measuring the height of the light and dark lines of the light source 10 using the optical axis height measuring instrument, the test environment of the light source 10 should be moved to the area to be measured, so as to ensure the consistency of the control variables.

[0101] After moving the light source 10 to the area to be measured, adjust the position of the optical axis height measuring instrument so that the distance between it and the light source 10 is also the preset length. This ensures the accuracy of the final measurement error calculation.

[0102] Further, please refer to Figure 4 , Figure 4 This is a flowchart illustrating the fourth embodiment of the low beam headlight brightness and darkness line calibration method of the present invention. After step S10, the method further includes:

[0103] Step S11: Adjust the optical axis of the light source 10 to be horizontal;

[0104] After step S51, the following is also included:

[0105] Step S53: Readjust the optical axis of the light source 10 to be horizontal.

[0106] A level is installed on the gimbal 20. There are two levels, which are perpendicular to each other, so that the optical axis of the light source 10 can be adjusted horizontally in two directions.

[0107] In this embodiment, the optical axis of the light source 10 is horizontally adjusted once before measurement using the illuminance meter 30, and again before measurement using the optical axis height measuring instrument. This ensures that the control variables are consistent in the two measurements, improving the accuracy of the measurement error calculation.

[0108] Further, please refer to Figure 5 , Figure 5This is a flowchart illustrating the fifth embodiment of the low beam headlight brightness and darkness line calibration method of the present invention. Step S30 includes:

[0109] Step S31: Adjust the light source 10 and the illuminance meter 30 to be on the same straight line;

[0110] Step S32: Adjust the detection surface of the illuminance meter 30 so that the detection surface of the illuminance meter 30 is perpendicular to the optical axis of the light source 10;

[0111] Step S33: Turn on the light source 10 and let the light source 10 illuminate the detection surface of the illuminance meter 30 so as to collect the illuminance of the light source 10 through the illuminance meter 30.

[0112] The measuring head of the illuminance meter 30 has a detection surface, which is used to receive the light emitted by the light source 10 and measure the corresponding illuminance.

[0113] In this embodiment, a cross laser pointer is used for adjustment. Positioning is achieved using the horizontal and vertical lines of the cross laser pointer, ensuring that the optical axis of the light source 10 and the center of the detection surface are on the same horizontal and vertical lines, thereby guaranteeing that the center of the detection surface of the illuminance meter 30 is perpendicular to the optical axis of the light source 10.

[0114] Similarly, step S60 includes:

[0115] Step S61: Adjust the light source 10 and the optical axis height measuring instrument to be on the same straight line;

[0116] Step S62: Adjust the detection surface of the optical axis height measuring instrument so that the detection surface of the optical axis height measuring instrument is perpendicular to the optical axis of the light source 10;

[0117] Step S63: Turn on the light source 10 and let the light source 10 illuminate the detection surface of the optical axis height measuring instrument, so as to collect the illuminance of the light source 10 through the optical axis height measuring instrument.

[0118] In this embodiment, the relative position between the light source 10 and the optical axis height measuring instrument is further ensured by the cross laser instrument, and the relative position between the light source 10 and the illuminance meter 30 is the same, thereby ensuring the consistency of control variables in the measurement process and improving the accuracy of measurement error calculation.

[0119] Further, please refer to Figure 6 , Figure 6 This is a flowchart illustrating the sixth embodiment of the low beam headlight brightness and darkness line calibration method of the present invention. Step S90 includes:

[0120] Step S91: Obtain the measurement value of the optical axis height measuring instrument;

[0121] Step S92: Calculate the calibration height based on the measured value and the measurement error.

[0122] The optical axis height measuring instrument is used to detect the vehicle under test in the test area. The algorithm of the optical axis height measuring instrument can directly calculate the height of the light and dark lines of the vehicle under test and record it as the measured value h0.

[0123] The measured value h0, the measurement error Δh, and the calibration height C satisfy the following formula:

[0124] Formula 2: C = h0 + Δh.

[0125] After adding the measurement error to the measured value, the resulting calibrated height is the actual value of the vehicle under test, thus improving the detection accuracy.

[0126] Furthermore, to address the aforementioned problems, this invention also proposes a low beam headlight brightness and darkness height calibration system, please refer to... Figure 7 The low beam headlight height calibration system includes a pan-tilt unit 20, an illuminance meter 30, an optical axis height measuring instrument, and a calculation module. The pan-tilt unit 20 is equipped with a light source 10 and is used to adjust the first height of the light source 10. The illuminance meter 30 is used to collect the illuminance value of the light source 10 and measure the second height of the headlight-dark line of the light source 10. The optical axis height measuring instrument is used to collect the illuminance value of the light source 10 and measure the third height of the headlight-dark line of the light source 10. The calculation module is used to calculate the measurement error based on the second and third heights, and to calculate the calibration height based on the measurement error.

[0127] In this embodiment, the light source 10 can be fixed on the gimbal 20, and the height of the light source 10 can be adjusted by the gimbal 20.

[0128] The first height is determined based on the vehicle model to be measured. For example, a standard vehicle is selected, and its tire pressure, number of occupants, fuel level, and other conditions are adjusted to ensure the standard vehicle is in normal operating condition for measurement, thereby improving detection accuracy. After adjustment, the distance from the center of the low beam headlight 10 of the standard vehicle to the ground is measured as the first height.

[0129] The light source 10 can be the same low beam headlight as that of a standard vehicle, and it is fixed on the gimbal 20. When adjusting the height of the light source 10, the distance from the center of the light source 10 to the ground surface is also used as the first height to ensure that the control variables are consistent.

[0130] After the initial height of the light source 10 is adjusted, the height of the light-dark line of the light source 10 should be measured in a standard environment, such as a laboratory environment free from other light interference, so that the measurement result is as close as possible to the actual height of the light-dark line of the light source 10. The distance between the light source 10 and the illuminance meter 30 should be adjusted to the preset length, which can be set between 10m and 15m, so that a clear light-dark line is visible when the beam of light from the light source 10 falls on the position of the illuminance meter 30.

[0131] It is understandable that areas above the light-dark line are either dark or have very low light intensity, while areas below the light-dark line have higher light intensity and are bright. Therefore, the difference in illuminance is greatest at the light-dark line.

[0132] The illuminance meter 30 includes a measuring head and a high-precision ruler, with the measuring head being adjustable in height on the high-precision ruler. When the light beam emitted by the light source 10 shines on the measuring head, the illuminance value of the light source 10 at that height position will be displayed on the measuring head.

[0133] By moving the measuring head up and down, when the measuring head moves from below the light-dark line to the critical position of the light-dark line, that is, just before the measuring head enters the dark height above the light-dark line, the first reading of the illuminance meter 30 is the first critical value. At this time, the height of the measuring head on the high-precision ruler is recorded as the second height.

[0134] After the second height measurement is completed, the illuminance meter 30 is replaced with an optical axis height measuring instrument.

[0135] The illuminance values ​​of the light source 10 at various locations are collected using the optical axis height measuring instrument. Similarly, at the position of the light-dark line, the collected illuminance value shows a sudden drop. Therefore, before entering the dark height just above the light-dark line, the second reading displayed on the optical axis height measuring instrument is the second critical value. At this time, the height of the optical axis height measuring instrument at the second critical value position is recorded as the third height.

[0136] The measurement error is calculated using the second height and the third height.

[0137] The second height H, the third height h, and the measurement error Δh satisfy the following formula:

[0138] Formula 1: Hh = △h.

[0139] During actual measurement, the headlights of the vehicle under test are shone onto the optical axis height measuring instrument. The height of the light and dark lines of the vehicle under test is measured by the optical axis height measuring instrument, and the calibration height of the vehicle under test is calculated by combining the measurement error. The calibration height is the actual height of the light and dark lines of the vehicle under test.

[0140] When the calibration height does not meet the regulatory requirements, the optical axis position of the low beam can be adjusted using a dimming screwdriver to make the light and dark lines meet the regulatory requirements.

[0141] The technical solution of this invention uses a light source 10 instead of a low beam headlight for detection, avoiding the low beam headlight height deviation caused by vehicle movement; and uses an adjustable illuminance meter 30 to determine the height of the light and dark line of the light source 10 by detecting the illuminance through the illuminance meter 30, eliminating the optical axis height deviation caused by manual visual inspection; during calibration, the height of the light source 10 during testing is detected by the optical axis height measuring instrument, and the measurement error is calculated based on the results of the two tests, so that in the subsequent testing of other vehicles, the actual height of the low beam headlight axis of other vehicles can be calculated by using the measurement error correction parameter, thus realizing the calibration function.

[0142] The above description is merely a preferred embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural transformations made using the contents of the present invention's specification and drawings under the inventive concept of the present invention, or direct / indirect applications in other related technical fields, are included within the patent protection scope of the present invention.

Claims

1. A method for calibrating the height of the light and dark lines of a low beam headlight, characterized in that, The method for calibrating the brightness and darkness line height of low beam headlights includes: Adjust the light source to the first height; An illuminance meter is set up, and the distance between the illuminance meter and the light source is set to a preset length; wherein, the distance between the light source and the illuminance meter is adjusted to the preset length so that when the light beam of the light source falls on the position of the illuminance meter, it can present a line of light and dark. The illuminance of the light source is collected by the illuminance meter. The height of the illuminance meter is adjusted until the first reading of the illuminance meter reaches the first critical value, and the second height corresponding to the first reading value being the first critical value is recorded; wherein, the area above the light-dark line is dark, and the area below the light-dark line is bright, the illuminance meter includes a measuring head, and the first reading of the illuminance meter is defined as the first critical value before the measuring head enters the height above the light-dark line where the area is dark during the process of the measuring head moving from below the light-dark line to above the light-dark line; Set up an optical axis height measuring instrument, and make the distance between the optical axis height measuring instrument and the light source the preset length; The illuminance of the light source is collected using the optical axis height measuring instrument. The second reading of illuminance on the optical axis height measuring instrument is obtained, and the third height corresponding to the second reading value being the second critical value is recorded; wherein, at the position of the light-dark line, the illuminance value collected by the optical axis height measuring instrument drops sharply; the second reading value displayed on the optical axis height measuring instrument is defined as the second critical value before the optical axis height measuring instrument enters the dark height above the light-dark line. The measurement error is calculated based on the second height and the third height; The calibration height is calculated based on the measurement error.

2. The method for calibrating the height of the low beam headlight's light and dark lines according to claim 1, characterized in that, The steps of adjusting the height of the illuminance meter until the first reading of the illuminance meter reaches the first critical value, and recording the second height corresponding to the first reading value being the first critical value, include: Move the illuminance meter from bottom to top and obtain the first reading of the illuminance meter; When the first reading value changes from a first preset value to a second preset value, the first preset value before changing to the second preset value is taken as the first threshold value; wherein, when the illuminance meter is in the bright area below the light-dark line, the first reading value is displayed as the first preset value; when the illuminance meter is in the dark area above the light-dark line, the first reading value is displayed as the second preset value; Record the second height corresponding to the first reading value when the first threshold value is reached.

3. The method for calibrating the height of the low beam headlight's light and dark lines according to claim 1, characterized in that, The steps of setting up an optical axis height measuring instrument and ensuring that the distance between the optical axis height measuring instrument and the light source is the preset length include: Move the light source to the area to be measured; The optical axis height measuring instrument is set in the area to be measured, and the distance between the optical axis height measuring instrument and the light source is the preset length.

4. The method for calibrating the height of the low beam headlight's light and dark lines according to claim 3, characterized in that, After adjusting the light source to the first height, the process also includes: Adjust the optical axis of the light source to be horizontal; After the step of moving the light source to the area to be measured, the method further includes: The optical axis of the light source is readjusted to be horizontal.

5. The method for calibrating the height of the low beam headlight's light and dark lines according to claim 1, characterized in that, The steps of collecting the illuminance of the light source using the illuminance meter include: Adjust the light source and the illuminance meter to be on the same straight line; Adjust the detection surface of the illuminance meter so that the detection surface of the illuminance meter is perpendicular to the optical axis of the light source; Turn on the light source and illuminate the detection surface of the illuminance meter to collect the illuminance of the light source through the illuminance meter.

6. The method for calibrating the brightness and darkness line height of low beam headlights according to claim 1, characterized in that, The steps of acquiring the illuminance of the light source using the optical axis height measuring instrument include: Adjust the light source and the optical axis height measuring instrument to be on the same straight line; Adjust the detection surface of the optical axis height measuring instrument so that the detection surface of the optical axis height measuring instrument is perpendicular to the optical axis of the light source; Turn on the light source and illuminate the detection surface of the optical axis height measuring instrument to collect the illuminance of the light source through the optical axis height measuring instrument.

7. The method for calibrating the height of the low beam headlight's light and dark lines according to claim 1, characterized in that, The second height H, the third height h, and the measurement error Δh satisfy the following relationship: Hh = △h.

8. The method for calibrating the height of the low beam headlight's light and dark lines according to claim 1, characterized in that, The steps for calculating the calibration height based on the measurement error include: Obtain the measured value from the optical axis height measuring instrument; The calibrated height is calculated based on the measured value and the measurement error.

9. The method for calibrating the height of the low beam headlight's light and dark lines according to claim 8, characterized in that, The measured value h0, the measurement error Δh, and the calibration height C satisfy the following relationship: C = h0 + Δh.

10. A low beam headlight brightness and darkness line calibration system, characterized in that, The low beam headlight brightness and darkness line calibration system includes: A gimbal, wherein a light source is provided on the gimbal, and the gimbal is used to adjust a first height of the light source; An illuminance meter is used to collect the illuminance value of the light source and measure the second height of the light-dark line of the light source; wherein, the area above the light-dark line is dark and the area below the light-dark line is bright. The illuminance meter includes a measuring head. As the measuring head moves from below the light-dark line to above the light-dark line, before the measuring head reaches the height above the light-dark line where the area is dark, the first reading of the illuminance meter is a first critical value, and the height of the measuring head on a high-precision ruler at this time is the second height. An optical axis height measuring instrument is used to collect the illuminance value of the light source and measure the third height of the light-dark line. Specifically, at the location of the light-dark line, the illuminance value collected by the optical axis height measuring instrument drops sharply. Before the optical axis height measuring instrument reaches a dark height above the light-dark line, a second reading displayed on the instrument is defined as a second critical value. The height at this second critical value position is defined as the third height. The calculation module is used to calculate the measurement error based on the second height and the third height, and to calculate the calibration height based on the measurement error.

Images