Test method and apparatus for vehicle head-up display screen

Abstract

This application relates to a method and apparatus for testing the image of a vehicle's head-up display (HUD). The method includes: constructing a test site that meets preset test standards; after controlling a vehicle to be tested that meets preset test conditions to drive to the test area of ​​the test site; receiving at least one test command from the HUD; and acquiring the display images of the HUD under different test commands; comparing the display images with the actual images under different test commands to obtain multiple comparison results; determining whether each comparison result meets the accuracy standard of the corresponding test command; and determining that the HUD is unqualified if at least one comparison result does not meet the accuracy standard. This solves the technical problems in related technologies, such as long testing time, low testing efficiency, inability to meet the requirements of rapid measurement on production lines, and the significant impact of the depth of field of the zoom lens on the testing accuracy of the virtual image distance, as well as the limited number of test angles.

Description

Technical Field

[0001] This application relates to the field of electronic and electrical technology, and in particular to a method and apparatus for testing the head-up display screen of a vehicle. Background Technology

[0002] A head-up display (HUD) is a new type of display device in cockpit products. Its principle is that the image on the HUD screen is reflected twice before being projected onto the windshield, displaying vehicle information, navigation, ADAS (Advanced Driver Assistance Systems) information, etc., allowing the driver to access relevant driving information without looking down at the instrument panel, thus increasing driving safety. Because the image is displayed on the windshield, an irregular plane, image correction becomes an essential and extremely difficult problem to solve.

[0003] In related technologies, when measuring the virtual image distance of a head-up display, an imaging luminance meter based on a zoom lens is used for measurement. By controlling the focal length of the camera and using the depth-of-field effect of the zoom lens, the boundary between clear and blurry images is determined to determine the virtual image distance.

[0004] However, the related technologies have long testing times and low testing efficiency, which cannot meet the requirements of rapid measurement on the production line. Furthermore, the depth of field of the zoom lens itself will seriously affect the testing accuracy of the virtual image distance, and the testing angle is limited, which needs to be improved. Summary of the Invention

[0005] This application provides a method and apparatus for testing the head-up display screen of a vehicle, in order to solve the technical problems in the related art, such as long testing time, low testing efficiency, inability to meet the requirements of rapid measurement on the production line, and the fact that the depth of field of the zoom lens itself will seriously affect the testing accuracy of the virtual image distance, and the limited number of testing angles.

[0006] The first aspect of this application provides a method for testing the image of a vehicle's head-up display (HUD), comprising the following steps: constructing a test site that meets preset test standards, and controlling a vehicle to be tested that meets preset test conditions to drive to a test area of ​​the test site; after the vehicle to be tested drives to the test area, receiving at least one test command from the HUD, and acquiring display images of the HUD under different test commands; comparing the display images with actual images under the different test commands to obtain multiple comparison results, determining whether each comparison result meets the accuracy standard of the corresponding test command, and determining that the HUD is unqualified if at least one comparison result does not meet the accuracy standard.

[0007] Optionally, in one embodiment of this application, constructing a test site that meets preset test standards includes: setting a projection background board that meets preset imaging conditions on one side of the test site, such that the projection background board is in front of the vehicle under test; adjusting the position of the test site so that the ambient light meets preset lighting conditions; setting a detection camera to acquire image data of the vehicle under test using the detection camera; positioning the projection background board and the vehicle under test respectively based on the image data; and adjusting the position of the vehicle under test using the positioning results until it is determined that the vehicle under test has driven into the test area.

[0008] Optionally, in one embodiment of this application, after controlling the vehicle under test that meets the preset test conditions to drive to the test area of ​​the test site, the method further includes: performing four-wheel alignment on the vehicle under test so that the positional error between the vehicle and the test area is less than a first preset threshold, and the tilt error between the vehicle and the test area is less than a second preset threshold; determining whether the windshield of the vehicle under test meets the preset cleaning standard; if the windshield does not meet the preset cleaning standard, generating a cleaning reminder signal; otherwise, controlling the vehicle under test to drive to the test area.

[0009] Optionally, in one embodiment of this application, the test instructions include at least one of the following: image size test instruction, lower viewing angle test instruction, left viewing angle test instruction, projection distance test instruction, image distortion rate test instruction, and ghost detection test instruction.

[0010] Optionally, in one embodiment of this application, when the test instruction is the image distortion rate test instruction, the method further includes: sending a display field of view boundary map to the head-up display based on the image distortion rate test instruction; acquiring an actual field of view boundary map displayed on the windshield using a camera installed inside the vehicle under test, wherein there are no obstructions between the camera and the projection background panel; calculating the image distortion rate of the head-up display using a preset distortion algorithm based on the display field of view boundary map and the actual field of view boundary map, so as to determine whether the head-up display meets the accuracy standard based on the image distortion rate.

[0011] Optionally, in one embodiment of this application, when the test instruction is the ghost detection test instruction, the method further includes: sending a display ghost detection image to the head-up display based on the ghost detection test instruction; using the camera to acquire an actual ghost detection image displayed on the windshield; and calculating the ghost accuracy of the head-up display based on the display ghost detection image and the actual ghost detection image, so as to determine whether the head-up display meets the accuracy standard based on the ghost accuracy.

[0012] Optionally, in one embodiment of this application, after determining that the head-up display is unqualified, the method further includes: obtaining a display image and an actual image corresponding to each comparison result that does not meet the preset accuracy standard; reading the first dot matrix coordinates of the display image and the corresponding second dot matrix coordinates of the actual image respectively; calculating the point deviation feature function between the first dot matrix coordinates and the second dot matrix coordinates, and forming a correction table from the matrix composed of the point deviation feature function; and writing the correction table into the internal memory of the head-up display to correct the display screen of the head-up display.

[0013] A second aspect of this application provides a testing device for a vehicle head-up display (HUD) image, comprising: a construction module for constructing a test site that meets preset test standards and controlling a vehicle under test that meets preset test conditions to drive to a test area of ​​the test site; a receiving module for receiving at least one test command from the HUD after the vehicle under test has driven to the test area, and acquiring display images of the HUD under different test commands; and a testing module for comparing the display images with actual images under the different test commands to obtain multiple comparison results, determining whether each comparison result meets the accuracy standard of the corresponding test command, and determining that the HUD is unqualified if at least one comparison result does not meet the accuracy standard.

[0014] Optionally, in one embodiment of this application, the construction module includes: a first setting unit, configured to set a projection background board that meets preset imaging conditions on one side of the test site, so that the projection background board is in front of the vehicle under test; an adjustment unit, configured to adjust the position of the test site so that the ambient light meets preset lighting conditions; and a second setting unit, configured to set a detection camera to acquire image data of the vehicle under test using the detection camera, locate the projection background board and the vehicle under test respectively based on the image data, and adjust the position of the vehicle under test using the positioning results until it is determined that the vehicle under test has driven to the test area.

[0015] Optionally, in one embodiment of this application, it further includes: a positioning module, used to perform four-wheel positioning on the vehicle under test, so that the positional error between the vehicle and the test area is less than a first preset threshold, and the tilt error between the vehicle and the test area is less than a second preset threshold; and a determination module, used to determine whether the windshield of the vehicle under test meets a preset cleaning standard. If the windshield does not meet the preset cleaning standard, a cleaning reminder signal is generated; otherwise, the vehicle under test is controlled to drive to the test area.

[0016] Optionally, in one embodiment of this application, the test instructions include at least one of the following: image size test instruction, lower viewing angle test instruction, left viewing angle test instruction, projection distance test instruction, image distortion rate test instruction, and ghost detection test instruction.

[0017] Optionally, in one embodiment of this application, when the test instruction is the image distortion rate test instruction, the test module further includes: a first sending unit, configured to send a display field of view boundary map to the head-up display based on the image distortion rate test instruction; a first acquisition unit, configured to acquire an actual field of view boundary map displayed on the windshield using a camera installed inside the vehicle under test, wherein there are no obstructions between the camera and the projection background panel; and a first calculation unit, configured to calculate the image distortion rate of the head-up display using a preset distortion algorithm based on the display field of view boundary map and the actual field of view boundary map, so as to determine whether the head-up display meets the accuracy standard based on the image distortion rate.

[0018] Optionally, in one embodiment of this application, when the test instruction is the ghost detection test instruction, the test module further includes: a second sending unit, configured to send a display ghost detection image to the head-up display based on the ghost detection test instruction; a second acquisition unit, configured to acquire an actual ghost detection image displayed on the windshield using the camera; and a second calculation unit, configured to calculate the ghost accuracy of the head-up display based on the display ghost detection image and the actual ghost detection image, so as to determine whether the head-up display meets the accuracy standard based on the ghost accuracy.

[0019] Optionally, in one embodiment of this application, it further includes: an acquisition module, configured to acquire a display image and an actual image corresponding to each comparison result that does not meet the preset accuracy standard; a reading module, configured to read the first dot matrix coordinates of the display image and the corresponding second dot matrix coordinates of the actual image respectively; a calculation module, configured to calculate the point deviation feature function between the first dot matrix coordinates and the second dot matrix coordinates, and form a correction table from the matrix composed of the point deviation feature function; and a storage module, configured to write the correction table into the internal memory of the head-up display to correct the display screen of the head-up display.

[0020] A third aspect of this application provides an electronic device, including: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement the vehicle head-up display screen testing method as described in the above embodiments.

[0021] A fourth aspect of this application provides a computer-readable storage medium storing computer instructions for causing the computer to perform the vehicle head-up display screen testing method as described in the above embodiments.

[0022] This application embodiment can construct a test site that meets preset test standards. After controlling a test vehicle that meets preset test conditions to drive to the test area of ​​the test site, it receives at least one test command from the head-up display (HUD) and collects the display images of the HUD under different test commands. The displayed images are then compared with the actual images under different test commands to obtain multiple comparison results. Each comparison result is judged to see if it meets the accuracy standard of the corresponding test command. If at least one comparison result does not meet the accuracy standard, the HUD is deemed unqualified. This improves the testing efficiency of the HUD, reduces testing errors caused by manual intervention, meets the rapid measurement needs of the production line, enables multi-directional testing, and the test results are beneficial for subsequent HUD calibration. Therefore, it solves the technical problems in related technologies, such as long testing time, low testing efficiency, inability to meet the requirements of rapid measurement on the production line, and the fact that the depth of field of the zoom lens itself significantly affects the testing accuracy of the virtual image distance, as well as the limited testing angles.

[0023] Additional aspects and advantages of this application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of this application. Attached Figure Description

[0024] The above and / or additional aspects and advantages of this application will become apparent and readily understood from the following description of the embodiments taken in conjunction with the accompanying drawings, wherein:

[0025] Figure 1 This is a flowchart of a method for testing the head-up display screen of a vehicle according to an embodiment of this application;

[0026] Figure 2 This is a schematic diagram of image size detection according to an embodiment of this application;

[0027] Figure 3 This is a schematic diagram of image distortion detection according to an embodiment of this application;

[0028] Figure 4 This is a schematic diagram of a distortion algorithm according to an embodiment of this application;

[0029] Figure 5 This is a schematic diagram of image ghosting detection according to an embodiment of this application;

[0030] Figure 6 This is a schematic diagram of the camera position according to an embodiment of this application;

[0031] Figure 7 This is a schematic diagram of vehicle posture according to an embodiment of this application;

[0032] Figure 8 This is a schematic diagram illustrating the principle of a head-up display screen testing method according to an embodiment of this application;

[0033] Figure 9 This is a flowchart of a head-up display screen testing method according to an embodiment of this application;

[0034] Figure 10 This is a schematic diagram illustrating the principle of a head-up display screen testing method according to another embodiment of this application;

[0035] Figure 11 This is a schematic diagram of a vehicle head-up display screen testing device according to an embodiment of this application;

[0036] Figure 12 This is a schematic diagram of the structure of an electronic device provided according to an embodiment of this application. Detailed Implementation

[0037] The embodiments of this application are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this application, and should not be construed as limiting this application.

[0038] The following describes a method and apparatus for testing the head-up display (HUD) image of a vehicle, according to embodiments of this application, with reference to the accompanying drawings. Addressing the issues mentioned in the background section, such as long testing times, low efficiency, inability to meet the requirements of rapid measurement on production lines, and limitations in the depth of field of zoom lenses significantly affecting the accuracy of virtual image distance testing, as well as the limited testing angles, this application provides a method for testing the HUD image of a vehicle. This method involves constructing a test area that meets preset testing standards. After controlling a vehicle to be tested, meeting the preset testing conditions, to drive to the test area of ​​the test area, at least one test command from the HUD is received. The displayed images of the HUD under different test commands are then acquired. These images are compared with the actual images under different test commands to obtain multiple comparison results. Each comparison result is then judged to meet the accuracy standard of the corresponding test command. If at least one comparison result does not meet the accuracy standard, the HUD is deemed unqualified. This improves the testing efficiency of the HUD, reduces testing errors caused by manual intervention, meets the requirements of rapid measurement on production lines, enables multi-directional testing, and the test results are beneficial for subsequent HUD calibration. This solves the technical problems in related technologies, such as long testing time, low testing efficiency, inability to meet the requirements of rapid measurement on the production line, and the fact that the depth of field of the zoom lens itself will seriously affect the testing accuracy of the virtual image distance, as well as the limited number of testing angles.

[0039] Specifically, Figure 1 This is a flowchart illustrating a method for testing the head-up display screen of a vehicle, as provided in an embodiment of this application.

[0040] like Figure 1 As shown, the testing method for the vehicle's head-up display screen includes the following steps:

[0041] In step S101, a test site that meets the preset test standards is constructed, and the vehicle to be tested that meets the preset test conditions is controlled to drive to the test area of ​​the test site.

[0042] In actual implementation, the embodiments of this application can pre-construct a test site that meets preset test standards for testing the head-up display screen of the vehicle, and after the test site is constructed, control the vehicle to be tested that meets the preset test conditions to drive to the test area of ​​the test site.

[0043] Among them, the test vehicle that meets the preset test conditions can be: all doors are closed; vehicle speed: 0km / h; vehicle power: ON; gearbox position: neutral or parking; occupant weight: no occupants; default suspension is in the zero position (subsequent coordinates are based on this); driver's side window is open.

[0044] Optionally, in one embodiment of this application, constructing a test site that meets preset test standards includes: setting a projection background board that meets preset imaging conditions on one side of the test site, so that the projection background board is in front of the vehicle under test; adjusting the position of the test site so that the ambient light meets preset lighting conditions; setting a detection camera to acquire image data of the vehicle under test using the detection camera, locating the projection background board and the vehicle under test respectively based on the image data, and adjusting the position of the vehicle under test using the positioning results until it is determined that the vehicle under test has driven into the test area.

[0045] For example, a test site that meets the preset test standards can be: specified lighting conditions: brightness ≥ 500 lux, light color temperature 6500K, and stable light environment (no flicker or color temperature fluctuation) (data confirmed by the equipment manufacturer); there should be a matte black background board in front of the vehicle, and the size of the background board should be large enough to cover the imaging area; the ambient light should be uniform, with no concentrated focused light spots on the projection background board; there should be no shadows on the projection background board; and there should be no obstructions between the test camera and the projection background board.

[0046] In step S102, after the vehicle under test drives to the test area, at least one test command from the head-up display is received, and the display images of the head-up display under different test commands are collected respectively.

[0047] Furthermore, in this embodiment of the application, after the vehicle under test drives to the test area, it can receive at least one test command for the head-up display and use a camera installed inside the vehicle under test to capture the display images of the head-up display under different test commands.

[0048] For example, the position of the camera installed inside the vehicle under test can be defined by the position of the camera housing. The relevant positioning can follow the coordinate system of the four-wheel alignment system; the positioning accuracy requirement for the camera inside the vehicle is ±1mm for each axis and ±0.1° for each axis rotation direction.

[0049] Optionally, in one embodiment of this application, after controlling the vehicle under test that meets the preset test conditions to drive to the test area of ​​the test site, the method further includes: performing four-wheel alignment on the vehicle under test so that the positional error between the vehicle and the test area is less than a first preset threshold and the tilt error between the vehicle and the test area is less than a second preset threshold; determining whether the windshield of the vehicle under test meets the preset cleaning standard; if the windshield does not meet the preset cleaning standard, generating a cleaning reminder signal; otherwise, controlling the vehicle under test to drive to the test area.

[0050] In some embodiments, after the vehicle under test, meeting preset test conditions, is driven to the test area of ​​the test site, the positioning of the vehicle under test can be detected using a detection force. This ensures that the positional error between the vehicle under test and the test area is less than a first preset threshold, and the tilt error between the vehicle and the test area is less than a second preset threshold. For example, the positional accuracy of the vehicle under test in the XY plane is + / -5mm; the tilt accuracy of the vehicle under test in the XZ plane is + / -3°. Simultaneously, it is determined whether the windshield of the vehicle under test meets a preset cleanliness standard. Since dirt can affect the detection results, a cleaning reminder signal can be generated to remind relevant personnel to clean it; otherwise, the test continues.

[0051] The test commands can include: image size test command, lower viewpoint test command, left viewpoint test command, projection distance test command, image distortion rate test command, and ghost detection test command.

[0052] In step S103, the displayed image is compared with the actual image under different test commands to obtain multiple comparison results. Each comparison result is judged to see if it meets the accuracy standard of the corresponding test command. If at least one comparison result does not meet the accuracy standard, the head-up display is deemed unqualified.

[0053] The process involves sending a display field-of-view boundary map to the head-up display (HUD) based on the image distortion rate test command; using a camera installed inside the vehicle under test to capture the actual field-of-view boundary map displayed on the windshield, where there are no obstructions between the camera and the projection background; and using a preset distortion algorithm to calculate the image distortion rate of the HUD based on the display field-of-view boundary map and the actual field-of-view boundary map, in order to determine whether the HUD meets the accuracy standard.

[0054] Specifically, based on the ghost detection test command, a ghost detection image is sent to the head-up display; an actual ghost detection image is captured on the windshield using a camera; and the ghost accuracy of the head-up display is calculated based on the displayed ghost detection image and the actual ghost detection image, so as to determine whether the head-up display meets the accuracy standard.

[0055] In actual implementation, the detection items in this application embodiment may include:

[0056] 1. Image size:

[0057] Once the vehicle under test and the camera are in place, the system connects to the industrial control computer's diagnostic system. Upon completion, a diagnostic command is sent to the head-up display (HUD) to show the field of view boundary map, such as... Figure 2 As shown. The camera captures the image displayed on the windshield, and the image size is calculated. The measurement system has an accuracy of 0.1° and a tolerance of ±6%.

[0058] 2. Downward viewing angle / projection distance:

[0059] The downward angle is the angle between the line connecting the optical reference point and the center of the virtual image and the XY plane.

[0060] Once the vehicle under test and the camera are in place, the system connects to the industrial control computer's diagnostic system. Upon completion, a diagnostic command is sent to the head-up display (HUD) to show the field of view boundary map, such as... Figure 2 As shown. The camera captures the image displayed on the windshield, and the downward viewing angle and projection distance of the image are calculated. The measurement system has an accuracy of 0.1° and a tolerance requirement of ±0.3°.

[0061] The downward viewing angle is optional and can be disregarded as a criterion for judgment. This is because the height of the head-up display image is adjustable, making the downward viewing angle variable.

[0062] 3. Left-hand perspective (reference item):

[0063] Once the vehicle under test and the camera are in place, the system connects to the industrial control computer's diagnostic system. Upon completion, a diagnostic command is sent to the head-up display (HUD) to show the field of view boundary map, such as... Figure 2 As shown. The camera captures the image displayed on the windshield, and the left-hand angle of the image is calculated. The measurement system has an accuracy of 0.1° and a tolerance of ±0.3°.

[0064] 4. Projection distance:

[0065] Once the vehicle under test and the camera are in place, the system connects to the industrial control computer's diagnostic system. Upon completion, a diagnostic command is sent to the head-up display (HUD) to show the field of view boundary map, such as... Figure 2 As shown. The camera captures the image displayed on the windshield, and the projection distance of the image is calculated. The measurement system has an accuracy of ±1mm and a tolerance requirement of ±6%.

[0066] 5. Image distortion rate:

[0067] Once the vehicle under test and the camera are in place, the system connects to the industrial control computer's diagnostic system. Upon completion, a diagnostic command is sent to the head-up display (HUD) to show the field of view boundary map, such as... Figure 3 The camera captures the image displayed on the windshield, and the image distortion rate is calculated. The measurement system has an accuracy of 1% and a distortion rate of <5%. Figure 4 The bitmap consists of 25x11 dots, with each dot being 8 pixels, and they need to be evenly distributed.

[0068] Distortion algorithms such as Figure 4 As shown, the projected black dot image is compared with the white dot image on the black baffle in front. The deviation values ​​Δx and Δy of the corresponding black and white points' x and y coordinates are taken, and the distance PD from the center point to this white point is taken. The distortion rate is calculated as follows:

[0069]

[0070] Calculation and judgment criteria:

[0071] Measure the horizontal and vertical deviation of each point from the ideal value and convert it into pixel values. Magnify the values ​​by 4 times and round them to the nearest integer (Δx and Δy).

[0072] If the distortion rate exceeds the set value, the corresponding parameters will be written to the head-up display (Δx and Δy are both values ​​magnified by 4 times and rounded down).

[0073]

[0074] Where ΔX and ΔY are represented by pixel values, representing the offset relative to the original image coordinates.

[0075] ΔX: Theoretical X-direction value - Actual X-direction value

[0076] ΔY: Theoretical Y-direction value - Actual Y-direction value.

[0077] If the final calculated distortion rate is greater than the judgment value, the correction parameters need to be written into the head-up display via a diagnostic command. The specific data transmission order is as follows: ΔX11, ΔY11, ..., ΔX1n, ΔY1n, ..., ΔXm1, ΔYm1, ..., ΔXmn, ΔYmn. Where m = 11 and n = 25.

[0078] 6. Ghosting detection:

[0079] Once the vehicle under test and the camera are in place, the system connects to the industrial control computer's diagnostic system. After completion, a diagnostic command is sent to the head-up display (HUD) to show the ghosting detection image, such as... Figure 5 As shown. The camera captures the image displayed on the windshield. If the image has ghosting, there will be two images, one real and one virtual, in the image. The ghosting is calculated. The measurement system accuracy is 0.1mm, and the ghosting is <1mrad.

[0080] Optionally, in one embodiment of this application, the display image and the actual image corresponding to each comparison result that does not meet the preset accuracy standard are obtained; the first dot matrix coordinates of the display image and the second dot matrix coordinates of the corresponding actual image are read respectively; the point deviation feature function between the first dot matrix coordinates and the second dot matrix coordinates is calculated, and the matrix composed of the point deviation feature function is used to form a correction table; the correction table is written into the internal memory of the head-up display to correct the display screen of the head-up display.

[0081] As one possible implementation, the embodiments of this application can also perform image correction, wherein the head-up display correction parameter table is written into the head-up display's internal memory through a diagnostic system; the coordinates of the actual points in the image are acquired by the camera system; the coordinates of the standard board dot matrix are suggested to be acquired by the camera system; and the correction table is a matrix composed of the characteristic function values ​​of the point deviation.

[0082] Combination Figures 2 to 10 As shown, the working principle of the vehicle head-up display screen testing method of this application embodiment is explained in detail with an example.

[0083] like Figures 6-8 As shown, the site layout and vehicle layout involved in the vehicle head-up display screen testing method of this application embodiment are the prerequisites for the detection.

[0084] The prerequisites include:

[0085] 1. Test vehicle conditions: All doors are closed; Vehicle speed: 0km / h; Vehicle power: ON; Gearbox position: Neutral or Park; Occupant weight: No occupants; Default suspension is at zero position (subsequent coordinates will be based on this); Driver's side window is open.

[0086] 2. Environmental conditions: such as Figure 6 As shown, a separate area is required for the head-up display (HUD) inspection station when the vehicle rolls off the production line. Equipment includes: a black front panel, a camera, and an industrial control computer. Natural light is required.

[0087] 3. Four-wheel alignment: Before the test begins, the vehicle to be tested must undergo four-wheel alignment to ensure that the vehicle is in a normal and accurate position, and to prevent the head-up display image from failing the test due to incorrect vehicle position.

[0088] 4. Specified site requirements: such as Figure 7 As shown, the positional accuracy of the vehicle under test in the XY plane is + / -5mm; the tilt accuracy of the vehicle under test in the XZ plane is + / -3°; the specified lighting conditions are: brightness ≥500 lux, light color temperature 6500K, and a stable lighting environment (no flicker or color temperature fluctuation) (data confirmed by the equipment manufacturer); there should be a matte black background board in front of the vehicle, and the size of the background board should be large enough to cover the imaging area; the ambient light should be uniform, with no concentrated focused light spots on the projection background board; there should be no shadows on the projection background board; there should be no obstructions between the detection camera and the projection background board; the windshield of the vehicle under test must be clean, as dirt will affect the detection results.

[0089] 5. Camera Position: The camera position is defined by the position of the eye box. The relevant positioning should follow the coordinate system of the four-wheel alignment system; the camera's positioning accuracy within the vehicle should be ±1mm for each axis and ±0.1° for each axis rotation direction; the camera's shooting points within the eye box range are as follows... Figure 8 As shown.

[0090] like Figure 9 and Figure 10 As shown, after all the preconditions are met, the detection items in this application embodiment may include:

[0091] 1. Image size:

[0092] Once the vehicle under test and the camera are in place, the system connects to the industrial control computer's diagnostic system. Upon completion, a diagnostic command is sent to the head-up display (HUD) to show the field of view boundary map, such as... Figure 2 As shown. The camera captures the image displayed on the windshield, and the image size is calculated. The measurement system has an accuracy of 0.1° and a tolerance of ±6%.

[0093] 2. Downward viewing angle / projection distance:

[0094] The downward angle is the angle between the line connecting the optical reference point and the center of the virtual image and the XY plane.

[0095] Once the vehicle under test and the camera are in place, the system connects to the industrial control computer's diagnostic system. Upon completion, a diagnostic command is sent to the head-up display (HUD) to show the field of view boundary map, such as... Figure 2 As shown. The camera captures the image displayed on the windshield, and the downward viewing angle and projection distance of the image are calculated. The measurement system has an accuracy of 0.1° and a tolerance requirement of ±0.3°.

[0096] The downward viewing angle is optional and can be disregarded as a criterion for judgment. This is because the height of the head-up display image is adjustable, making the downward viewing angle variable.

[0097] 3. Left-hand perspective (reference item):

[0098] Once the vehicle under test and the camera are in place, the system connects to the industrial control computer's diagnostic system. Upon completion, a diagnostic command is sent to the head-up display (HUD) to show the field of view boundary map, such as... Figure 2 As shown. The camera captures the image displayed on the windshield, and the left-hand angle of the image is calculated. The measurement system has an accuracy of 0.1° and a tolerance of ±0.3°.

[0099] 4. Projection distance:

[0100] Once the vehicle under test and the camera are in place, the system connects to the industrial control computer's diagnostic system. Upon completion, a diagnostic command is sent to the head-up display (HUD) to show the field of view boundary map, such as... Figure 2As shown. The camera captures the image displayed on the windshield, and the projection distance of the image is calculated. The measurement system has an accuracy of ±1mm and a tolerance requirement of ±6%.

[0101] 5. Image distortion rate:

[0102] Once the vehicle under test and the camera are in place, the system connects to the industrial control computer's diagnostic system. Upon completion, a diagnostic command is sent to the head-up display (HUD) to show the field of view boundary map, such as... Figure 3 The camera captures the image displayed on the windshield, and the image distortion rate is calculated. The measurement system has an accuracy of 1% and a distortion rate of <5%. Figure 4 The bitmap consists of 25x11 dots, with each dot being 8 pixels, and they need to be evenly distributed.

[0103] Distortion algorithms such as Figure 4 As shown, the projected black dot image is compared with the white dot image on the black baffle in front. The deviation values ​​Δx and Δy of the corresponding black and white points' x and y coordinates are taken, and the distance PD from the center point to this white point is taken. The distortion rate is calculated as follows:

[0104]

[0105] Calculation and judgment criteria:

[0106] Measure the horizontal and vertical deviation of each point from the ideal value and convert it into pixel values. Magnify the values ​​by 4 times and round them to the nearest integer (Δx and Δy).

[0107] If the distortion rate exceeds the set value, the corresponding parameters will be written to the head-up display (Δx and Δy are both values ​​magnified by 4 times and rounded down).

[0108]

[0109] Where ΔX and ΔY are represented by pixel values, representing the offset relative to the original image coordinates.

[0110] ΔX: Theoretical X-direction value - Actual X-direction value

[0111] ΔY: Theoretical Y-direction value - Actual Y-direction value.

[0112] If the final calculated distortion rate is greater than the judgment value, the correction parameters need to be written into the head-up display via a diagnostic command. The specific data transmission order is as follows: ΔX11, ΔY11, ..., ΔX1n, ΔY1n, ..., ΔXm1, ΔYm1, ..., ΔXmn, ΔYmn. Where m = 11 and n = 25.

[0113] 6. Ghosting detection:

[0114] Once the vehicle under test and the camera are in place, the system connects to the industrial control computer's diagnostic system. After completion, a diagnostic command is sent to the head-up display (HUD) to show the ghosting detection image, such as... Figure 5 As shown. The camera captures the image displayed on the windshield. If the image has ghosting, there will be two images, one real and one virtual, in the image. The ghosting is calculated. The measurement system accuracy is 0.1mm, and the ghosting is <1mrad.

[0115] Furthermore, embodiments of this application can perform image correction based on the detection results: the head-up display correction parameter table is written into the head-up display's internal memory via a diagnostic system. The coordinates of the actual points in the image are captured by the camera system. It is recommended to use the coordinates of the standard board dot matrix captured by the camera system. The correction table is a matrix composed of the characteristic function values ​​of the point deviation.

[0116] In this embodiment, the ghost distance test image, the image distortion test image, the imaging size, the downward viewing angle, the projection distance, and the image rotation test image can also be preset.

[0117] When performing image distortion calculation, Tester can be used to calculate and generate distortion calibration data, and write the calculated image distortion rate calibration value. In actual execution, this embodiment can wait 10 seconds after writing to ensure that the calibration data takes effect.

[0118] In addition, this application embodiment can also test other optional items: read the head-up display product number; read the head-up display software / hardware version; read the head-up display calibration status (if this step is required, the calibration status must be read before and after testing to prevent calibration failure); write the vehicle body VIN number; write the factory ID.

[0119] The vehicle head-up display (HUD) image testing method proposed in this application can construct a test site that meets preset test standards. After controlling the vehicle under test, which meets the preset test conditions, to drive to the test area of ​​the test site, it receives at least one test command from the HUD and collects the display images of the HUD under different test commands. The displayed images are then compared with the actual images under different test commands to obtain multiple comparison results. Each comparison result is judged to meet the accuracy standard of the corresponding test command. If at least one comparison result does not meet the accuracy standard, the HUD is deemed unqualified. This improves the testing efficiency of the HUD, reduces testing errors caused by manual intervention, meets the rapid measurement requirements of the production line, enables multi-directional testing, and the test results are beneficial for subsequent HUD calibration. Therefore, this method solves the technical problems in related technologies, such as long testing time, low testing efficiency, inability to meet the requirements of rapid measurement on the production line, and the significant impact of the depth of field of the zoom lens on the testing accuracy of the virtual image distance, as well as the limited number of test angles.

[0120] Next, referring to the accompanying drawings, a test apparatus for a vehicle head-up display screen according to an embodiment of this application is described.

[0121] Figure 11 This is a block diagram of a vehicle head-up display screen testing device according to an embodiment of this application.

[0122] like Figure 11 As shown, the head-up display screen testing device 10 for the vehicle includes: a construction module 100, a receiving module 200, and a testing module 300.

[0123] Specifically, the construction module 100 is used to construct a test site that meets preset test standards and control the test vehicle that meets preset test conditions to drive to the test area of ​​the test site.

[0124] The receiving module 200 is used to receive at least one test command from the head-up display after the vehicle under test has driven to the test area, and to acquire the display images of the head-up display under different test commands.

[0125] The test module 300 is used to compare the displayed image with the actual image under different test instructions to obtain multiple comparison results. It then determines whether each comparison result meets the accuracy standard of the corresponding test instruction. If at least one comparison result does not meet the accuracy standard, the head-up display is deemed unqualified.

[0126] Optionally, in one embodiment of this application, the construction module 100 includes: a first setting unit, an adjustment unit, and a second setting unit.

[0127] The first setting unit is used to set a projection background board that meets the preset imaging conditions on one side of the test site, so that the projection background board is in front of the vehicle under test.

[0128] The adjustment unit is used to adjust the position of the test site so that the ambient light meets the preset lighting conditions.

[0129] The second setting unit is used to set up the detection camera to acquire image data of the vehicle under test, locate the projection background board and the vehicle under test according to the image data, and adjust the position of the vehicle under test according to the positioning results until it is determined that the vehicle under test has driven to the test area.

[0130] Optionally, in one embodiment of this application, the vehicle head-up display screen testing device 10 further includes a positioning module and a determination module.

[0131] The positioning module is used to perform four-wheel positioning on the vehicle under test, so that the positional error between the vehicle and the test area is less than a first preset threshold and the tilt error between the vehicle and the test area is less than a second preset threshold.

[0132] The determination module is used to determine whether the windshield of the vehicle under test meets the preset cleaning standards. If the windshield does not meet the preset cleaning standards, a cleaning reminder signal is generated; otherwise, the vehicle under test is controlled to drive to the testing area.

[0133] Optionally, in one embodiment of this application, the test instructions include at least one of the following: image size test instruction, lower viewpoint test instruction, left viewpoint test instruction, projection distance test instruction, image distortion rate test instruction, and ghost detection test instruction.

[0134] Optionally, in one embodiment of this application, when the test instruction is a screen distortion rate test instruction, the test module 300 further includes: a first sending unit, a first acquisition unit, and a first calculation unit.

[0135] The first sending unit is used to send a display field of view boundary map to the head-up display based on the image distortion rate test command.

[0136] The first acquisition unit is used to acquire the actual field-of-view boundary map displayed on the windshield using a camera installed inside the vehicle under test, wherein there are no obstructions between the camera and the projection background.

[0137] The first calculation unit is used to calculate the image distortion rate of the head-up display based on the displayed field of view boundary map and the actual field of view boundary map using a preset distortion algorithm, so as to determine whether the head-up display meets the accuracy standard based on the image distortion rate.

[0138] Optionally, in one embodiment of this application, when the test instruction is a ghosting detection test instruction, the test module 300 further includes: a second sending unit, a second acquisition unit, and a second calculation unit.

[0139] The second sending unit is used to send a ghost detection map to the head-up display based on the ghost detection test command.

[0140] The second acquisition unit is used to acquire the actual ghosting detection image displayed on the windshield using a camera.

[0141] The second calculation unit is used to calculate the ghosting accuracy of the head-up display based on the displayed ghosting detection map and the actual ghosting detection map, so as to determine whether the head-up display meets the accuracy standard based on the ghosting accuracy.

[0142] Optionally, in one embodiment of this application, the vehicle head-up display screen testing device 10 further includes: an acquisition module, a reading module, a calculation module, and a storage module.

[0143] The acquisition module is used to obtain the display image and the actual image corresponding to each comparison result that does not meet the preset accuracy standard.

[0144] The reading module is used to read the first dot matrix coordinates of the displayed image and the corresponding second dot matrix coordinates of the actual image, respectively.

[0145] The calculation module is used to calculate the point deviation characteristic function between the coordinates of the first lattice and the coordinates of the second lattice, and to form a correction table from the matrix composed of the point deviation characteristic functions.

[0146] The storage module is used to write the correction form into the head-up display's internal memory to correct the head-up display's display.

[0147] It should be noted that the foregoing explanation of the vehicle head-up display screen testing method embodiment also applies to the vehicle head-up display screen testing device of this embodiment, and will not be repeated here.

[0148] The vehicle head-up display (HUD) image testing device proposed in this application can construct a test site that meets preset test standards. After controlling a vehicle to be tested that meets preset test conditions to drive to the test area of ​​the test site, it receives at least one test command from the HUD and collects the display images of the HUD under different test commands. The displayed images are then compared with the actual images under different test commands to obtain multiple comparison results. Each comparison result is judged to meet the accuracy standard of the corresponding test command. If at least one comparison result does not meet the accuracy standard, the HUD is deemed unqualified. This improves the testing efficiency of the HUD, reduces testing errors caused by manual intervention, meets the rapid measurement requirements of the production line, enables multi-directional testing, and the test results are beneficial for subsequent HUD calibration. Therefore, it solves the technical problems in related technologies, such as long testing time, low testing efficiency, inability to meet the requirements of rapid measurement on the production line, and the fact that the depth of field of the zoom lens itself significantly affects the testing accuracy of the virtual image distance, as well as the limited testing angles.

[0149] Figure 12 A schematic diagram of the structure of an electronic device provided in an embodiment of this application. The electronic device may include:

[0150] The memory 1201, the processor 1202, and the computer program stored on the memory 1201 and executable on the processor 1202.

[0151] When the processor 1202 executes the program, it implements the vehicle head-up display screen testing method provided in the above embodiments.

[0152] Furthermore, electronic devices also include:

[0153] Communication interface 1203 is used for communication between memory 1201 and processor 1202.

[0154] The memory 1201 is used to store computer programs that can run on the processor 1202.

[0155] The memory 1201 may include high-speed RAM memory, and may also include non-volatile memory, such as at least one disk storage device.

[0156] If the memory 1201, processor 1202, and communication interface 1203 are implemented independently, then the communication interface 1203, memory 1201, and processor 1202 can be interconnected via a bus to complete communication between them. The bus can be an Industry Standard Architecture (ISA) bus, a Peripheral Component Interconnect (PCI) bus, or an Extended Industry Standard Architecture (EISA) bus, etc. Buses can be divided into address buses, data buses, control buses, etc. For ease of representation, Figure 12 The bus is represented by a single thick line, but this does not mean that there is only one bus or one type of bus.

[0157] Optionally, in a specific implementation, if the memory 1201, processor 1202, and communication interface 1203 are integrated on a single chip, then the memory 1201, processor 1202, and communication interface 1203 can communicate with each other through an internal interface.

[0158] The processor 1202 may be a central processing unit (CPU), an application specific integrated circuit (ASIC), or one or more integrated circuits configured to implement the embodiments of this application.

[0159] This embodiment also provides a computer-readable storage medium storing a computer program that, when executed by a processor, implements the above-described method for testing the head-up display screen of a vehicle.

[0160] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0161] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying 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 application, "N" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0162] Any process or method described in the flowchart or otherwise herein can be understood as representing a module, segment, or portion of code comprising one or N executable instructions for implementing custom logic functions or processes, and the scope of the preferred embodiments of this application includes additional implementations in which functions may be performed not in the order shown or discussed, including substantially simultaneously or in reverse order depending on the functions involved, as should be understood by those skilled in the art to which embodiments of this application pertain.

[0163] The logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as a sequenced list of executable instructions for implementing logical functions, and can be embodied in any computer-readable medium for use by, or in conjunction with, an instruction execution system, apparatus, or device (such as a computer-based system, a processor-included system, or other system that can fetch and execute instructions from, an instruction execution system, apparatus, or device). For the purposes of this specification, "computer-readable medium" can be any means that can contain, store, communicate, propagate, or transmit programs for use by, or in conjunction with, an instruction execution system, apparatus, or device. More specific examples (a non-exhaustive list) of computer-readable media include: an electrical connection having one or more wires (electronic device), a portable computer disk drive (magnetic device), random access memory (RAM), read-only memory (ROM), erasable and editable read-only memory (EPROM or flash memory), fiber optic devices, and portable optical disc read-only memory (CDROM). Alternatively, the computer-readable medium may be paper or other suitable media on which the program can be printed, since the program can be obtained electronically by optically scanning the paper or other medium, followed by editing, interpreting, or otherwise processing as necessary, and then stored in a computer memory.

[0164] It should be understood that the various parts of this application can be implemented using hardware, software, firmware, or a combination thereof. In the above embodiments, the N steps or methods can be implemented using software or firmware stored in memory and executed by a suitable instruction execution system. For example, if implemented in hardware as in another embodiment, it can be implemented using any one or a combination of the following techniques known in the art: discrete logic circuits having logic gates for implementing logical functions on data signals, application-specific integrated circuits (ASICs) having suitable combinational logic gates, programmable gate arrays (PGAs), field-programmable gate arrays (FPGAs), etc.

[0165] Those skilled in the art will understand that all or part of the steps of the methods described in the above embodiments can be implemented by a program instructing related hardware. The program can be stored in a computer-readable storage medium, and when executed, it includes one or a combination of the steps of the method embodiments.

[0166] Furthermore, the functional units in the various embodiments of this application can be integrated into a processing module, or each unit can exist physically separately, or two or more units can be integrated into a module. The integrated module can be implemented in hardware or as a software functional module. If the integrated module is implemented as a software functional module and sold or used as an independent product, it can also be stored in a computer-readable storage medium.

[0167] The storage medium mentioned above can be a read-only memory, a disk, or an optical disk, etc. Although embodiments of this application have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting this application. Those skilled in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of this application.

Claims

1. A method for testing the image of a vehicle's head-up display, characterized in that, Includes the following steps: Construct a test site that meets the preset test standards, and control the test vehicle that meets the preset test conditions to drive to the test area of ​​the test site; After the vehicle under test drives to the test area, it receives multiple test commands from the head-up display and captures the display images of the head-up display under different test commands. The displayed image is compared with the actual image under different test commands to obtain multiple comparison results. Each comparison result is judged to determine whether it meets the accuracy standard of the corresponding test command. If at least one comparison result does not meet the accuracy standard, the head-up display is determined to be unqualified. The test commands include: image size test command, lower viewpoint test command, left viewpoint test command, projection distance test command, image distortion rate test command, and ghost detection test command. In the case where the test command is the image distortion rate test command, the method further includes: sending a display field of view boundary map to the head-up display based on the image distortion rate test command; acquiring an actual field of view boundary map displayed on the windshield using a camera installed inside the vehicle under test, wherein there are no obstructions between the camera and the projection background panel; calculating the image distortion rate of the head-up display using a preset distortion algorithm based on the display field of view boundary map and the actual field of view boundary map, and determining whether the head-up display meets the accuracy standard based on the image distortion rate; Wherein, when the test instruction is the ghost detection test instruction, the method further includes: sending a display ghost detection image to the head-up display based on the ghost detection test instruction; using the camera to acquire an actual ghost detection image displayed on the windshield; calculating the ghost accuracy of the head-up display based on the display ghost detection image and the actual ghost detection image, so as to determine whether the head-up display meets the accuracy standard based on the ghost accuracy.

2. The method according to claim 1, characterized in that, The construction of a test site that meets preset test standards includes: A projection background board that meets preset imaging conditions is set on one side of the test site so that the projection background board is in front of the vehicle under test. Adjust the position of the test site so that the ambient light meets the preset lighting conditions; A detection camera is set up to acquire image data of the vehicle under test. The projection background and the vehicle under test are located based on the image data. The position of the vehicle under test is adjusted based on the positioning results until it is determined that the vehicle under test has driven into the test area.

3. The method according to claim 1, characterized in that, After controlling the vehicle under test, which meets the preset test conditions, to drive to the test area of ​​the test site, the process further includes: Four-wheel alignment is performed on the vehicle under test so that the positional error between the vehicle and the test area is less than a first preset threshold and the tilt error between the vehicle and the test area is less than a second preset threshold. Determine whether the windshield of the vehicle under test meets the preset cleaning standard. If the windshield does not meet the preset cleaning standard, generate a cleaning reminder signal; otherwise, control the vehicle under test to drive to the test area.

4. The method according to claim 1, characterized in that, After determining that the head-up display is defective, the process also includes: Obtain the display image and the actual image corresponding to each comparison result that does not meet the accuracy standard; Read the first dot matrix coordinates of the displayed image and the corresponding second dot matrix coordinates of the actual image, respectively; Calculate the point deviation characteristic function between the first point matrix coordinates and the second point matrix coordinates, and form a correction table from the matrix composed of the point deviation characteristic function; The correction table is written into the internal memory of the head-up display to correct the display screen.

5. A testing device for a vehicle head-up display screen, characterized in that, include: The construction module is used to construct a test site that meets preset test standards and control the test vehicle that meets preset test conditions to drive to the test area of ​​the test site. The receiving module is used to receive at least one test command from the head-up display after the vehicle under test has driven to the test area, and to acquire the display images of the head-up display under different test commands respectively. The testing module is used to compare the displayed image with the actual image under different test commands to obtain multiple comparison results, determine whether each comparison result meets the accuracy standard of the corresponding test command, and determine that the head-up display is unqualified if at least one comparison result does not meet the accuracy standard. The test commands include: image size test command, lower viewpoint test command, left viewpoint test command, projection distance test command, image distortion rate test command, and ghost detection test command. When the test instruction is the image distortion rate test instruction, the test module further includes: a first sending unit, used to send a display field of view boundary map to the head-up display based on the image distortion rate test instruction; a first acquisition unit, used to acquire an actual field of view boundary map displayed on the windshield using a camera installed inside the vehicle under test, wherein there are no obstructions between the camera and the projection background; and a first calculation unit, used to calculate the image distortion rate of the head-up display based on the display field of view boundary map and the actual field of view boundary map using a preset distortion algorithm, so as to determine whether the head-up display meets the accuracy standard based on the image distortion rate; When the test instruction is the ghost detection test instruction, the test module further includes: a second sending unit, used to send a display ghost detection image to the head-up display based on the ghost detection test instruction; a second acquisition unit, used to acquire an actual ghost detection image displayed on the windshield using the camera; and a second calculation unit, used to calculate the ghost accuracy of the head-up display based on the display ghost detection image and the actual ghost detection image, so as to determine whether the head-up display meets the accuracy standard based on the ghost accuracy.

6. An electronic device, characterized in that, include: A memory, a processor, and a computer program stored in the memory and executable on the processor, the processor executing the program to implement the head-up display screen testing method for a vehicle as described in any one of claims 1-4.

7. A computer-readable storage medium having a computer program stored thereon, characterized in that, The program is executed by the processor to implement the head-up display screen testing method for vehicles as described in any one of claims 1-4.

Images