Automatic calibration method, system and storage medium for vehicle-mounted laser inertial group

Abstract

The present invention relates to a calibration method for a vehicle-mounted laser inertial group to be inspected, and specifically to an automated calibration method, system and storage medium for a vehicle-mounted laser inertial group. The method solves the problems of complex process, high cost, long cycle and easy error in existing calibration, compensation and precision testing. After the vehicle-mounted laser inertial group to be inspected is unloaded from the vehicle, the automated calibration, compensation and precision testing of the inertial group can be quickly realized in the calibration room of the shooting range, and the group can be loaded onto the vehicle after passing the precision test. The entire test process only requires one tester to operate in strict accordance with the user manual, which greatly improves the calibration accuracy and efficiency of the entire system, shortens the calibration test and loading time, reduces the calibration test cost, reduces the risk of human operation errors, and meets the requirements of rapid calibration.

Description

Technical Field

[0001] The present invention relates to a calibration method for a vehicle-mounted laser inertial system to be inspected, and in particular to an automated calibration method, system and storage medium for a vehicle-mounted laser inertial system. Background Art

[0002] To meet training and maintenance needs throughout its lifecycle, the laser inertial unit (LIU) undergoes a calibration cycle two years after installation. Upon completion, the unit must be removed from the vehicle for calibration, compensation, and accuracy testing. This process involves numerous modules, is complex, and places high demands on precision, requiring stringent operator control. Currently, manual testing of the LIS is a complex process for testers, requiring the coordination of multiple personnel. This requires significant initial training and training for specialized testers on how to operate and control the turntable, power control device, and basic knowledge of the LIS. This results in significant labor and material costs, as well as a lengthy calibration and testing cycle. Furthermore, current calibration, compensation, and accuracy testing cannot be performed until the LIS returns to the factory, further extending the calibration and testing cycle. Furthermore, manual operation can easily lead to operational errors, invalidating test data. Summary of the Invention

[0003] The purpose of the present invention is to provide a method for automated calibration, compensation and precision testing of a vehicle-mounted laser inertial group, so as to solve the problems of the existing calibration, compensation and precision testing, such as the complex process, high cost, long cycle and easy error. By adopting the method of the present invention, the vehicle-mounted laser inertial group to be tested can quickly realize the automated calibration, compensation and precision testing of the inertial group in the calibration room of the shooting range after it is unloaded from the vehicle, and can be loaded onto the vehicle after passing the precision test. The entire test process only requires one tester to operate in strict accordance with the user manual, which greatly improves the calibration accuracy and efficiency of the entire system, shortens the calibration test and loading time, reduces the calibration test cost, reduces the risk of human operation errors, and meets the requirements of rapid calibration.

[0004] The technical solution of the present invention is to provide an automated calibration method for a vehicle-mounted laser inertial system, which is special in that it includes the following steps:

[0005] Step 1: Install the vehicle-mounted laser inertial group to be inspected;

[0006] Step 1.1. Remove the vehicle-mounted laser inertial group to be inspected together with the upper base plate and fix them on the turntable located in the calibration room of the shooting range;

[0007] Step 1.2: Power on the turntable and the laser inertial group on the vehicle to be inspected in sequence;

[0008] Step 1.3: Balance the turntable and loosen the pitch axis locking pin on the turntable body;

[0009] Step 2: Communication detection;

[0010] Communication test to ensure that the power supply serial port of the on-board laser inertial group to be inspected, the turntable communication serial port, the on-board laser inertial group test serial port to be inspected, and the on-board laser inertial group client serial port are communicating normally;

[0011] Step 3: Calibration;

[0012] Step 3.1: Receive the self-calibration command and control the turntable to rotate the vehicle-mounted laser inertial system (LIRS) to be inspected in sequence according to the preset 19 calibration positions. After rotating to each calibration position, collect and count the pulse signals of each channel of the vehicle-mounted LRS to obtain calibration test data.

[0013] Step 3.2, control the inner and outer frames of the turntable to return to zero;

[0014] Step 4: Calibration test data burning;

[0015] Package the calibration test data generated in step 3 according to the set format, and burn the packaged calibration test data into the vehicle-mounted laser inertial group to be tested;

[0016] Step 5: Compensation test;

[0017] Step 5.1: Control the laser inertial group on the vehicle to be inspected to perform x1 times of eight-direction north-seeking on the turntable to obtain the north-seeking values ​​of 8x1 positions;

[0018] Step 5.2: Based on the true north values ​​of 8x1 positions and the north-seeking values ​​of 8x1 positions, obtain the x1 times eight-azimuth north-seeking errors, and then determine the heading effect deviation value;

[0019] Step 5.3, write the heading effect deviation value into the internal parameter file of the vehicle-mounted laser inertial system to be inspected;

[0020] Step 5.4: Calculate the heading 3RMS value based on the heading effect deviation value, combined with the attitude angle test value and true value of the laser inertial group of the vehicle to be tested at the i-th position, and compensate the heading 3RMS value in the calibration test data to generate the final calibration data;

[0021] Step 6: Accuracy verification;

[0022] Control the laser inertial group of the vehicle to be inspected to perform x2 times of eight-direction north-seeking on the turntable. After the north-seeking is completed, hold the heading for the set time and calculate the relevant parameters. According to the calculation results and judgment criteria, determine whether the laser inertial group of the vehicle to be inspected is calibrated. If it is unqualified, return to step 3 and recalibrate. Otherwise, complete the calibration and turn off the laser inertial group of the vehicle to be inspected and the turntable.

[0023] Furthermore, in order to improve the calibration accuracy, step 3.1 is repeated three times to obtain three sets of calibration test data; in step 4, the three sets of calibration test data are averaged, packaged according to the set format, and the packaged calibration test data is burned into the vehicle-mounted laser inertial group to be tested.

[0024] Furthermore, the nineteen calibration positions preset in step 3.1 are as follows:

[0025] Position number External frame angle (°)(Z) Inner frame angle (°)(X) Rotate 90° 0 0 0 Around -Z axis 1 270 0 Around +Z axis 2 0 0 Around +Z axis 3 90 0 Around +Z axis 4 180 0 Around -Z axis 5 90 0 Around -Z axis 6 0 0 Around -Z axis 7 270 0 Around +X axis 8 270 90 Around +Z axis 9 0 90 Around +Z axis 10 90 90 Around +Z axis 11 180 90 Around -Z axis 12 90 90 Around -Z axis 13 0 90 Around -Z axis 14 270 90 Around +X axis 15 270 180 Around +X axis 16 270 270 Around -X axis 17 270 180 Around -X axis 18 270 90 Around -X axis 19 270 0 Around +Z axis 0 0 0 Initial position .

[0026] Furthermore, in step 5.1, x1 is equal to 2, and the second eight-direction north search position is as follows:

[0027] Position number Turntable inner frame(°) 1 0 2 45 3 90 4 135 5 180 6 225 7 270 8 315 9 0 10 45 11 90 12 135 13 180 14 225 15 315 .

[0028] Furthermore, the second eight-azimuth north-finding error in step 5.2 is calculated according to the following formula:

[0029] Δ i =γ i -θ i

[0030] Among them, i=0,1,...15, θ i is the true north value of the 16 positions in step 5.1, where θ0=θ, θ1=θ+45, θ2=θ+90, θ3=θ+135, θ4=θ+180, θ5=θ+225, θ6=θ+270, θ7=θ+315, θ8=θ, θ9=θ+45, θ 10 =θ+90,θ3=θ+135,θ 12 =θ+180,θ 13 =θ+225,θ 14 =θ+270,θ 15 =θ+315;γ i is the north-seeking value of the ith position among the 16 positions obtained in step 5.1.

[0031] Furthermore, in step 5.2, the heading effect deviation value Δ is calculated according to the following formula:

[0032] Δ=3600*∑Δ i / 16.

[0033] Furthermore, in step 5.4, the heading 3RMS value is calculated according to the following formula:

[0034]

[0035] Among them, k is the attitude angle of the laser inertial group on the vehicle to be inspected, which are the heading angle Ф, the pitch angle β, and the roll angle ψ, respectively. kiis the error between the test value and the true value of the attitude angle (heading angle Φ, pitch angle β, roll angle ψ) of the vehicle-mounted laser inertial system to be inspected at the i-th position;

[0036] where X ki Calculated by the following formula:

[0037] X ki =θ ki测 -θ k0

[0038] Among them, θ ki测 is the attitude angle (heading angle, pitch angle, roll angle) test value of the vehicle-mounted laser inertial group to be tested at the i-th position, Represents the heading angle test value of the vehicle-mounted laser inertial system to be tested, θ βi测 Represents the pitch angle test value of the vehicle-mounted laser inertial system to be tested, θ ψi测 Represents the roll angle test value of the vehicle-mounted laser inertial system to be tested;

[0039] θ k0 is the true value of the attitude angle (heading angle, pitch angle, roll angle) of the onboard laser inertial system to be inspected at the i-th position, Represents the true value of the heading angle of the vehicle-mounted laser inertial system to be inspected, θ β0 Represents the true value of the pitch angle of the vehicle-mounted laser inertial system to be inspected, θ ψ0 Represents the true value of the roll angle of the laser inertial system on the vehicle to be inspected;

[0040] θ k0 Calculated by the following formula:

[0041] θ k0 =θ′1+Δ

[0042] Wherein, θ′1 is the attitude angle test value of the vehicle-mounted laser inertial system when the turntable is rotated to 0 degrees and the theodolite is aimed at the prism of the vehicle-mounted laser inertial system, and Δ is the heading effect deviation value.

[0043] Furthermore, the heading effect deviation value Δ is calculated according to the following formula:

[0044] Δ=((γ1-θ′1)+(γ2-θ′2)) / 2

[0045] γ1 is the north-seeking value of the vehicle-mounted laser inertial system test when the turntable rotates to 0 degrees;

[0046] θ′1 is the attitude angle test value of the vehicle-mounted laser inertial system when the turntable rotates to 0 degrees and the theodolite is aimed at the prism of the vehicle-mounted laser inertial system;

[0047] γ2 is the north-seeking value of the vehicle-mounted laser inertial group test when the turntable rotates to 45 degrees;

[0048] θ′2 is the attitude angle test value of the vehicle-mounted laser inertial system to be tested when the turntable is rotated to 45 degrees and the theodolite is aimed at the prism of the vehicle-mounted laser inertial system to be tested.

[0049] Furthermore, θ′1 and θ′2 are calculated by the following formulas:

[0050] θ′1=(λ+μ1)+β1·tan((ν1)*pi / 180)+90

[0051] θ′2=(λ+μ2)+β2·tan((ν2)*pi / 180)+90

[0052] Wherein, λ is the reference angle of the true north reference; μ1 is the horizontal angle when the turntable is rotated to 0 degrees and the theodolite is aimed at the prism of the vehicle-mounted laser inertial system to be tested; β1 is the pitch angle test value of the vehicle-mounted laser inertial system to be tested when the turntable is rotated to 0 degrees and the theodolite is aimed at the prism of the vehicle-mounted laser inertial system to be tested; ν1 is the vertical angle when the turntable is rotated to 0 degrees and the theodolite is aimed at the vehicle-mounted laser inertial system to be tested; pi is the circumference of a circle;

[0053] μ2 is the horizontal angle when the turntable is rotated to 45 degrees and the theodolite is aimed at the vehicle-mounted laser inertial unit (LIU) to be inspected; β2 is the pitch angle test value of the vehicle-mounted laser inertial unit (LIU) to be inspected when the turntable is rotated to 45 degrees and the theodolite is aimed at the prism of the vehicle-mounted laser inertial unit (LIU); ν2 is the vertical angle when the turntable is rotated to 45 degrees and the theodolite is aimed at the vehicle-mounted laser inertial unit (LIU) to be inspected.

[0054] Furthermore, in step 6, the relevant parameters include the standard deviation of the heading angle error, the standard deviation of the pitch angle attitude error, the standard deviation of the roll angle attitude error, the static azimuth keeping accuracy, the static linear velocity keeping accuracy and the horizontal positioning accuracy. The judgment criteria include: the standard deviation value of the heading angle error 3RMS ≤ 1.5'; the standard deviation value of the pitch angle and roll angle errors 3RMS ≤ 0.016°; the static azimuth keeping accuracy is not greater than 0.01 (°) / h; the static linear velocity keeping accuracy -1 ≤ V E ≤1 and -1≤V N ≤1 (unit: m / s); where V E is the eastward velocity, V N is the north velocity; the static navigation positioning accuracy (50% CEP) value is less than or equal to 1nm / h (5h).

[0055] Furthermore, the static bearing keeping accuracy is determined according to the following formula: γ = |γ1′-γ2′|;

[0056] Where γ1′ is the heading angle measurement value of the laser inertial system of the vehicle to be inspected at the current moment, which is read 1 minute after the completion of north-seeking; γ2′ is the heading angle measurement value of the laser inertial system of the vehicle to be inspected at the current moment, which is read 1 hour later.

[0057] The present invention also provides an automated calibration and testing system for a vehicle-mounted laser inertial group, characterized in that it includes a memory and a processor, wherein the memory stores a computer program, and when the computer program is executed by the processor, the process of steps 3 to 6 above is implemented.

[0058] The present invention also provides a computer-readable storage medium, characterized in that a computer program is stored thereon, and when the computer program is executed, the process of steps 3 to 6 above is implemented.

[0059] The beneficial effects of the present invention are:

[0060] 1. The present invention can truly realize the automatic calibration of the vehicle-mounted laser inertial group without human intervention. The entire work process can be completed by one person without switching back and forth between various software. One-click operation can be directly realized to automatically complete the power switch control, turntable control and laser inertial group calibration, compensation and accuracy detection. The test data and results are uniformly given by the software, avoiding errors and mistakes caused by human calculation and operation, and improving the calibration accuracy.

[0061] 2. This invention optimizes the workflow while ensuring truly controllable testing procedures. This reduces staff workload, shortens testing time, and lowers labor costs. This improves overall system calibration efficiency, shortens calibration time, and mitigates technical risks, freeing up a significant number of test personnel. Furthermore, it meets the military's requirements for rapid calibration. BRIEF DESCRIPTION OF THE DRAWINGS

[0062] Figure 1 This is a flow chart of the automated calibration method for a vehicle-mounted laser inertial system according to the present invention;

[0063] Figure 2 This is a flow chart of communication detection in the automated calibration method of the vehicle-mounted laser inertial group according to the present invention;

[0064] Figure 3 This is a calculation flow chart after the calibration process in the automated calibration method of the vehicle-mounted laser inertial group according to the present invention;

[0065] Figure 4 This is a compensation test flow chart for the automated calibration method of the vehicle-mounted laser inertial system of the present invention;

[0066] Figure 5 This is a flowchart of the accuracy verification in the automated calibration method of the vehicle-mounted laser inertial group of the present invention. DETAILED DESCRIPTION

[0067] To make the above-mentioned objects, features, and advantages of the present invention more clearly understood, the following detailed description of the specific embodiments of the present invention is given in conjunction with the accompanying drawings. It is obvious that the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary persons in this field without creative work should fall within the scope of protection of the present invention.

[0068] In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention may also be implemented in other ways different from those described herein. Those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0069] Secondly, the term "embodiment" as used herein refers to specific features, structures, or characteristics that may be included in at least one implementation of the present invention. The phrases "in other embodiments" that appear in various places throughout this specification do not necessarily refer to the same embodiment, nor do they refer to separate or selective embodiments that are mutually exclusive with other embodiments.

[0070] Before installing the inertial group, it is necessary to determine the installation position and related requirements of the turntable in the range calibration room:

[0071] a) When installing the turntable, it is required to be installed on a vibration-isolating foundation; the installation orientation must also be fixed. After the pitch and azimuth axes are zeroed, the turntable's support block is on the north side and the connector is on the east side. That is, the axis end mirror of the outer frame axis is required to point to the east, and the installation angle must be within 1.5 degrees.

[0072] b) When aiming, the north datum error must be no greater than 5", and the north datum must be calibrated regularly in accordance with relevant requirements. The north datum must be installed on a vibration-isolating foundation. Prisms that do not meet the requirements or are out of calibration cannot be used. The height of the north datum must be as consistent as possible with the height of the prism of the inertial group (approximately 1.5m, the specific height is based on actual measurement after the turntable is installed). When aiming with a theodolite, the theodolite must use the flat aiming method when aiming at the prism.

[0073] c) Turntable position accuracy requirements: The position accuracy of the turntable's pitch and azimuth axes must be better than 0.0005° under load, and the load-bearing capacity must be no less than 80kg. The position accuracy of the turntable must not be affected by long-term load bearing. The position accuracy must be inspected annually.

[0074] d) Turntable horizontal accuracy requirements: When no load (inertial group) is applied, after the turntable is powered on and returns to zero, two high-precision levels (with a resolution of at least 0.2") are placed vertically on the turntable surface. The turntable is controlled to rotate the azimuth axis 360°. The shims on the turntable base are adjusted. The horizontal accuracy must reach 2" for one full rotation. This item requires annual inspection.

[0075] e) Regarding the reference direction of theodolite and prism: The output of theodolite should be the optical aiming angle value of the angle between the inner normal of the prism and the north direction, with the value of north-north being positive. The prism reference should be the optical aiming angle value of the angle between the inner normal of the reference prism and the north direction, with the value of north-north being positive.

[0076] f) All power cables and communication serial port cables must be reliably connected to ensure there are no connection faults. Annual inspection is required. Pitch axis trim is required.

[0077] like Figure 1 As shown, this embodiment implements the automated calibration of the vehicle-mounted laser inertial system through the following process:

[0078] Step 1: Install the laser inertial group on the vehicle to be inspected;

[0079] Remove the onboard laser inertial unit (IMU) from the vehicle to be inspected, along with the upper base plate. Secure it to the turntable according to the specified installation method. Connect the cables as required. Power on the turntable, industrial computer, and onboard IMU to be inspected, in sequence. Level the turntable and loosen the pitch axis locking pins on the turntable body.

[0080] Step 2: Communication detection;

[0081] like Figure 2 As shown, the power supply serial port of the on-board laser inertial group to be inspected, the turntable communication serial port, the test serial port of the on-board laser inertial group to be inspected and the client serial port of the on-board laser inertial group to be inspected are checked in turn to see if they are connected normally and the communication is normal.

[0082] Step 3: Calibration;

[0083] When the inertia group preheating time is up, click the "Calibrate" button on the industrial computer to automatically perform calibration according to the following process:

[0084] a) After receiving the self-calibration command, first memorize the local latitude and gravity acceleration;

[0085] b) Then control the inner and outer frames of the turntable to unlock, so that the vehicle-mounted laser inertial group to be inspected can be flipped in sequence according to the preset 19 calibration positions;

[0086] The preset nineteen calibration positions are as follows:

[0087] Position number External frame angle (°)(Z) Inner frame angle (°)(X) Rotate 90° 0 0 0 Around -Z axis 1 270 0 Around +Z axis 2 0 0 Around +Z axis 3 90 0 Around +Z axis 4 180 0 Around -Z axis 5 90 0 Around -Z axis 6 0 0 Around -Z axis 7 270 0 Around +X axis 8 270 90 Around +Z axis 9 0 90 Around +Z axis 10 90 90 Around +Z axis 11 180 90 Around -Z axis 12 90 90 Around -Z axis 13 0 90 Around -Z axis 14 270 90 Around +X axis 15 270 180 Around +X axis 16 270 270 Around -X axis 17 270 180 Around -X axis 18 270 90 Around -X axis 19 270 0 Around +Z axis 0 0 0 Initial position

[0088] c) After the first position is placed, wait for no less than 10 seconds before starting data collection; the sampling time for each position is 330 seconds. When the sampling time for each position reaches 300 seconds, start flipping to the next position. This dynamic flipping process is completed within 30 seconds. Repeat this process until all 19 positions are flipped. The pulse signals of each channel of the inertial group are collected and counted to generate calibration test data E 1X 、E 1Y 、E 1Z 、E 0X 、E 0Y 、E 0Z 、E XY 、E YX 、E ZY 、E YZ 、E XZ 、E ZX , K 1X , K 1Y , K 1Z , K 0X , K 0Y , K 0Z , K XY , K YX , K ZY , K YZ , K XZ , K ZX . E 0X 、E 0Y 、E 0Z is the gyro zero position, E 1X 、E 1Y 、E 1Z is the gyro calibration factor, E XY 、E YX 、E ZY 、E YZ 、E XZ 、E ZX K is the gyro installation error. 0X , K 0Y , K 0Z is the accelerometer zero position, K 1X , K 1Y , K 1Z is the accelerometer calibration factor, K XY , K YX , K ZY , K YZ , K XZ , K ZX To improve the calibration accuracy, repeat this step three times to obtain three sets of calibration test data.

[0089] d) Control the inner and outer frames of the turntable to return to zero.

[0090] Step 4: Calculate the parameters and write the calculation results into the laser inertial group of the vehicle to be tested;

[0091] like Figure 3 , click the "Parameter Calculation" button, the software will automatically calculate the three calibration test data in sequence according to the software requirements and average the three test results, and finally save the averaged data.

[0092] After the parameter calculation is completed, the parameter burning box will automatically pop up. Click the "Parameter Burn" button. The software will automatically package the saved calibration test data in a certain format, communicate with the on-board laser inertial group to be tested through the asynchronous serial bus, and burn the packaged calibration test data into the on-board laser inertial group to be tested.

[0093] Step 5: Compensation test;

[0094] like Figure 4 As shown, click the "Compensation Test" button, and the software automatically controls the inertial group to perform two eight-azimuth north search on the turntable, sending five initial alignment commands to the inertial group in each azimuth. Finally, the heading 3RMS value is calculated based on the local true north value, and the test result is compensated in the calibration test data to generate the final calibration data. The details are as follows:

[0095] Step 5.1: Control the vehicle-mounted laser inertial group to be inspected to perform eight-azimuth north-seeking twice on the turntable to obtain north-seeking values ​​at 16 positions. In other embodiments, eight-azimuth north-seeking can be performed a set number of times according to actual needs, such as three or four times.

[0096] The second eight-direction north search positions are as follows:

[0097]

[0098]

[0099] Step 5.2: Based on the true north values ​​of the 16 positions and the north-seeking values ​​of the 16 positions, obtain the eight-azimuth north-seeking errors twice, and then determine the heading effect deviation value;

[0100] The second eight-azimuth north-finding error is calculated according to the following formula:

[0101] Δ i =γ i -θ i

[0102] Among them, i=0,1,...15, θ iis the true north value of the 16 positions in step 5.1, where θ0=θ, θ1=θ+45, θ2=θ+90, θ3=θ+135, θ4=θ+180, θ5=θ+225, θ6=θ+270, θ7=θ+315, θ8=θ, θ9=θ+45, θ 10 =θ+90,θ3=θ+135,θ 12 =θ+180,θ 13 =θ+225,θ 14 =θ+270,θ 15 =θ+315;γ i is the north-seeking value of the ith position among the 16 positions obtained in step 5.1.

[0103] The heading effect deviation value Δ is calculated according to the following formula:

[0104] Δ=3600*∑Δ i / 16.

[0105] Step 5.3, write the heading effect deviation value into the internal parameter file of the vehicle-mounted laser inertial group to be tested; the specific method is: through the vehicle-mounted laser inertial group raw data communication test port, use the program parameter fixing software to read the parameter file inside the vehicle-mounted laser inertial group, and then set the parameter "delta" in the 10th row and 4th column to -Δ (unit: ") (the value of delta is -Δ) according to the format of Table 3, convert the changed parameter file into the "*.bin" format using the fixing software, and burn the "*.bin" format file into the navigation computer circuit through the program parameter fixing software.

[0106] Table 3 Parameter format

[0107]

[0108]

[0109] Step 5.4: Calculate the heading 3RMS value based on the heading effect deviation value, combined with the attitude angle test value and true value of the laser inertial group of the vehicle to be tested at the i-th position, and compensate the heading 3RMS value in the calibration test data to generate the final calibration data;

[0110]

[0111] Among them, k is the attitude angle of the laser inertial group on the vehicle to be inspected, which are the heading angle Ф, the pitch angle β, and the roll angle ψ, respectively. ki is the error between the test value and the true value of the attitude angle (heading angle Φ, pitch angle β, roll angle ψ) of the vehicle-mounted laser inertial system to be inspected at the i-th position;

[0112] where X ki Calculated by the following formula:

[0113] X ki =θ ki测 -θ k0

[0114] Among them, θ ki测 is the attitude angle (heading angle, pitch angle, roll angle) test value of the vehicle-mounted laser inertial group to be tested at the i-th position, Represents the heading angle test value of the vehicle-mounted laser inertial system to be tested, θ βi测 Represents the pitch angle test value of the vehicle-mounted laser inertial system to be tested, θ ψi测 Represents the roll angle test value of the vehicle-mounted laser inertial system to be tested;

[0115] θ k0 is the true value of the attitude angle (heading angle, pitch angle, roll angle) of the onboard laser inertial system to be inspected at the i-th position, Represents the true value of the heading angle of the vehicle-mounted laser inertial system to be inspected, θ β0 Represents the true value of the pitch angle of the vehicle-mounted laser inertial system to be inspected, θ ψ0 Represents the true value of the roll angle of the laser inertial system on the vehicle to be inspected;

[0116] θ k0 Calculated by the following formula:

[0117] θ k0 =θ′1+Δ

[0118] Wherein, θ′1 is the attitude angle test value of the vehicle-mounted laser inertial system when the turntable is rotated to 0 degrees and the theodolite is aimed at the prism of the vehicle-mounted laser inertial system, and Δ is the heading effect deviation value.

[0119] The heading effect deviation value Δ is calculated according to the following formula:

[0120] Δ=((γ1-θ′1)+(γ2-θ′2)) / 2

[0121] γ1 is the north-seeking value of the vehicle-mounted laser inertial system test when the turntable rotates to 0 degrees;

[0122] θ′1 is the attitude angle test value of the vehicle-mounted laser inertial system when the turntable rotates to 0 degrees and the theodolite is aimed at the prism of the vehicle-mounted laser inertial system;

[0123] γ2 is the north-seeking value of the vehicle-mounted laser inertial group test when the turntable rotates to 45 degrees;

[0124] θ′2 is the attitude angle test value of the vehicle-mounted laser inertial system to be tested when the turntable is rotated to 45 degrees and the theodolite is aimed at the prism of the vehicle-mounted laser inertial system to be tested.

[0125] θ′1 and θ′2 are calculated by the following formulas:

[0126] θ′1=(λ+μ1)+β1·tan((ν1)*pi / 180)+90

[0127] θ′2=(λ+μ2)+β2·tan((ν2)*pi / 180)+90

[0128] Wherein, λ is the reference angle of the true north reference; μ1 is the horizontal angle when the turntable is rotated to 0 degrees and the theodolite is aimed at the prism of the vehicle-mounted laser inertial system to be tested; β1 is the pitch angle test value of the vehicle-mounted laser inertial system to be tested when the turntable is rotated to 0 degrees and the theodolite is aimed at the prism of the vehicle-mounted laser inertial system to be tested; ν1 is the vertical angle when the turntable is rotated to 0 degrees and the theodolite is aimed at the vehicle-mounted laser inertial system to be tested; pi is the circumference of a circle;

[0129] μ2 is the horizontal angle when the turntable is rotated to 45 degrees and the theodolite is aimed at the vehicle-mounted laser inertial unit (LIU) to be inspected; β2 is the pitch angle test value of the vehicle-mounted laser inertial unit (LIU) to be inspected when the turntable is rotated to 45 degrees and the theodolite is aimed at the prism of the vehicle-mounted laser inertial unit (LIU); ν2 is the vertical angle when the turntable is rotated to 45 degrees and the theodolite is aimed at the vehicle-mounted laser inertial unit (LIU) to be inspected.

[0130] Step 6: Accuracy verification;

[0131] like Figure 5 As shown, click the "Accuracy Verification" button, the software automatically controls the inertial group to search for north in all directions on the turntable, and then performs the heading hold function for 5 hours after the north search is completed. Finally, the standard deviation of the heading angle error, the standard deviation of the pitch angle attitude error, the standard deviation of the roll angle attitude error, the static holding accuracy, the static navigation positioning accuracy, and the east speed V are calculated. E Accuracy, north direction is speed V N Accuracy: The final determination of whether the inertial group calibration is qualified is based on the calculation results and judgment criteria. If it is unqualified, recalibration is required.

[0132] The judgment criteria are as follows: the standard deviation of the heading angle error 3RMS ≤ 1.5'; the standard deviation of the pitch angle and roll angle error 3RMS ≤ 0.016°; the static azimuth holding accuracy is no more than 0.01 (°) / h; the static linear velocity holding accuracy is -1 ≤ V E ≤1 and -1≤V N ≤1 (unit: m / s); where V E is the eastward velocity, V N is the north velocity; the static navigation positioning accuracy (50% CEP) value is less than or equal to 1nm / h (5h).

[0133] The static bearing keeping accuracy is determined according to the following formula: γ = |γ1′-γ2′|;

[0134] Where γ1′ is the north-seeking value of the laser inertial group of the vehicle to be inspected at the current moment, read 1 minute after the north-seeking is completed; γ2′ is the north-seeking value of the laser inertial group of the vehicle to be inspected at the current moment, read another 1 hour later.

[0135] The static navigation positioning accuracy (50% CEP) is calculated according to the following formula:

[0136]

[0137]

[0138]

[0139] Δλ i =60×(λ 测试i -λ 真值 )

[0140] Where: is the latitude test value of the vehicle-mounted laser inertial system to be inspected for the i-th time, unit: °; is the true latitude value, unit: °; λ 测试i is the longitude test value of the vehicle-mounted laser inertial system to be tested for the i-th time, unit: °; λ 真值 is the true longitude value, unit: °; is the latitude error of the ith test, unit: ′; Δλ i is the longitude error of the ith test, unit: ′. i is the time of the i-th trial, Unit: h; 50% CEP - static navigation positioning accuracy, unit: nm / h; n is the number of valid tests; RER i is the radial error of the ith test, unit: nm / h.

[0141] Step 7: Automatically shut down the system after the test is completed, which includes:

[0142] 1) Software controls the mechanical lock of the inner and outer axes of the turntable;

[0143] 2) Software control turns off the power of the laser inertial group;

[0144] 3) Turn off the turntable power supply under software control;

[0145] 4) Manually turn off the turntable industrial computer and power control button.

[0146] This embodiment further discloses an automated calibration and testing system for a vehicle-mounted laser inertial system, comprising a memory and a processor. The memory stores a computer program, and when the computer program is executed by the processor, the above-mentioned processes of steps 3 to 7 are implemented.

[0147] This embodiment further discloses a computer-readable storage medium having a computer program stored thereon. When the computer program is executed, the process of steps 3 to 7 described above is implemented. In some possible implementations, the present invention may also be implemented in the form of a program product, which includes program code. When the program product is executed on a terminal device, the program code is used to cause the terminal device to execute the steps according to various exemplary embodiments of the present invention described in the above method section of this specification.

[0148] The program product for implementing the above method may be a portable compact disc read-only memory (CD-ROM) and include program code, and can be run on a terminal device, such as a personal computer. However, the program product of the present invention is not limited thereto. In the present invention, a computer-readable storage medium may be any tangible medium containing or storing a program that can be used by or in conjunction with an instruction execution system, apparatus, or device.

[0149] The program product may employ any combination of one or more readable media. The readable medium may be a readable signal medium or a readable storage medium. The readable storage medium may be, for example, but not limited to, an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, device, or component, or any combination thereof. More specific examples (a non-exhaustive list) of readable storage media include: an electrical connection with one or more wires, a portable disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination thereof.

Claims

1. An automated calibration method for a vehicle-mounted laser inertial system, characterized in that: The following steps are involved: Step 1: Install the vehicle-mounted laser inertial group to be inspected; Step 1.

1. Remove the vehicle-mounted laser inertial group to be inspected together with the upper base plate and fix them on the turntable located in the calibration room of the shooting range; Step 1.2: Power on the turntable and the laser inertial group on the vehicle to be inspected in sequence; Step 1.3: Balance the turntable and loosen the pitch axis locking pin on the turntable body; Step 2: Communication detection; Communication test to ensure that the power supply serial port of the on-board laser inertial group to be inspected, the turntable communication serial port, the on-board laser inertial group test serial port to be inspected, and the on-board laser inertial group client serial port are communicating normally; Step 3: Calibration; Step 3.1: Receive the self-calibration command and control the turntable to rotate the vehicle-mounted laser inertial system (LIRS) to be inspected in sequence according to the preset 19 calibration positions. After rotating to each calibration position, collect and count the pulse signals of each channel of the vehicle-mounted LRS to obtain calibration test data. Step 3.2, control the inner and outer frames of the turntable to return to zero; Step 4: Calibration test data burning; Package the calibration test data generated in step 3 according to the set format, and burn the packaged calibration test data into the vehicle-mounted laser inertial group to be tested; Step 5: Compensation test; Step 5.1, control the laser inertial group of the vehicle to be inspected to perform x1 times of north-seeking in eight directions on the turntable to obtain north-seeking values ​​of 8x1 positions, where x1 is an integer greater than or equal to 1; Step 5.2: Based on the true north values ​​of 8x1 positions and the north-seeking values ​​of 8x1 positions, obtain the x1 times eight-azimuth north-seeking errors, and then determine the heading effect deviation value; Step 5.3, write the heading effect deviation value into the internal parameter file of the vehicle-mounted laser inertial system to be inspected; Step 5.4: Calculate the heading 3RMS value based on the heading effect deviation value, combined with the attitude angle test value and true value of the laser inertial group of the vehicle to be tested at the i-th position, and compensate the heading 3RMS value in the calibration test data to generate the final calibration data; Calculate the heading 3RMS value according to the following formula: Among them, k is the attitude angle of the laser inertial group on the vehicle to be inspected, which are the heading angle Ф, the pitch angle β, and the roll angle ψ, respectively. ki is the error between the attitude angle test value and the true value of the vehicle-mounted laser inertial system to be inspected at the i-th position; where X ki Calculated by the following formula: X ki =θ ki测 -θ k0 Among them, θ ki测 is the attitude angle test value of the vehicle-mounted laser inertial group to be tested at the i-th position, Represents the heading angle test value of the vehicle-mounted laser inertial system to be tested, θ βi测 Represents the pitch angle test value of the vehicle-mounted laser inertial system to be tested, θ ψi测 Represents the roll angle test value of the vehicle-mounted laser inertial system to be tested; θ k0 is the true value of the attitude angle of the vehicle-mounted laser inertial system to be inspected at the i-th position, Represents the true value of the heading angle of the vehicle-mounted laser inertial system to be inspected, θ β0 Represents the true value of the pitch angle of the vehicle-mounted laser inertial system to be inspected, θ ψ0 Represents the true value of the roll angle of the laser inertial system on the vehicle to be inspected; θ k0 Calculated by the following formula: i k0 =θ′1+Δ Where θ′1 is the attitude angle test value of the vehicle-mounted laser inertial system when the turntable is rotated to 0 degrees and the theodolite is aimed at the prism of the vehicle-mounted laser inertial system. Δ is the heading effect deviation value, which is calculated according to the following formula: Δ=((γ1-θ′1)+(γ2-θ′2)) / 2 γ1 is the north-seeking value of the vehicle-mounted laser inertial system test when the turntable rotates to 0 degrees; θ′1 is the attitude angle test value of the vehicle-mounted laser inertial system when the turntable rotates to 0 degrees and the theodolite is aimed at the prism of the vehicle-mounted laser inertial system; γ2 is the north-seeking value of the vehicle-mounted laser inertial group test when the turntable rotates to 45 degrees; θ′2 is the attitude angle test value of the vehicle-mounted laser inertial system when the turntable is rotated to 45 degrees and the theodolite is aimed at the prism of the vehicle-mounted laser inertial system; θ′1 and θ′2 are calculated by the following formulas: θ′1=(λ+μ1)+β1·tan((ν1)*pi / 180)+90 θ′2=(λ+μ2)+β2·tan((ν2)*pi / 180)+90 Wherein, λ is the reference angle of the true north reference; μ1 is the horizontal angle when the turntable is rotated to 0 degrees and the theodolite is aimed; β1 is the pitch angle test value of the onboard laser inertial group to be tested when the turntable is rotated to 0 degrees; ν1 is the vertical angle when the turntable is rotated to 0 degrees and the theodolite is aimed at the onboard laser inertial group to be tested; pi is the circumference of a circle; μ2 is the horizontal angle when the turntable is rotated to 45 degrees and the theodolite is aimed at the laser inertial unit (IMU) on the vehicle to be inspected; β2 is the pitch angle test value of the laser inertial unit (IMU) on the vehicle to be inspected when the turntable is rotated to 45 degrees; ν2 is the vertical angle when the turntable is rotated to 45 degrees and the theodolite is aimed at the laser inertial unit (IMU) on the vehicle to be inspected; Step 6: Accuracy verification; Control the laser inertial group of the vehicle to be inspected to perform x2 eight-azimuth north-seeking on the turntable, where x2 is an integer greater than or equal to 1. After the north-seeking is completed, perform heading maintenance for a set time, calculate relevant parameters, and determine whether the calibration of the laser inertial group of the vehicle to be inspected is qualified based on the calculation results and judgment criteria. If it is unqualified, return to step 3 and recalibrate. Otherwise, complete the calibration and shut down the laser inertial group of the vehicle to be inspected and the turntable. The relevant parameters include the standard deviation of the heading angle error, the standard deviation of the pitch angle attitude error, the standard deviation of the roll angle attitude error, the static heading maintenance accuracy, the static linear velocity maintenance accuracy and the horizontal positioning accuracy. The judgment criteria include: the standard deviation value of the heading angle error 3RMS ≤ 1.5'; the standard deviation value of the pitch angle and roll angle errors 3RMS ≤ 0.016°; the static heading maintenance accuracy is not greater than 0.01 (°) / h; the static linear velocity maintenance accuracy -1 ≤ V E ≤1 and -1≤V N ≤1, unit m / s; where V E is the eastward velocity, V N is the north velocity; the static navigation positioning accuracy is less than or equal to 1nm / h.

2. The automated calibration method for a vehicle-mounted laser inertial system according to claim 1, characterized in that: Repeat step 3.1 three times to obtain three sets of calibration test data; in step 4, average the three sets of calibration test data, package them according to the set format, and burn the packaged calibration test data into the vehicle-mounted laser inertial group to be tested.

3. The automated calibration method for a vehicle-mounted laser inertial system according to claim 2, characterized in that: The nineteen calibration positions preset in step 3.1 are as follows: 。 4. The automated calibration method for a vehicle-mounted laser inertial system according to claim 3, characterized in that: In step 5.1, x1 is equal to 2, and the position of the second eight-direction north search is as follows: 。 5. The automated calibration method for a vehicle-mounted laser inertial system according to claim 4, characterized in that: The second eight-azimuth north-finding error in step 5.2 is calculated using the following formula: D i =c i -θ i Among them, i=0,1,...15, θ i is the true north value of the 16 positions in step 5.1, where θ0=θ, θ1=θ+45, θ2=θ+90, θ3=θ+135, θ4=θ+180, θ5=θ+225, θ6=θ+270, θ7=θ+315, θ8=θ, θ9=θ+45, θ 10 =θ+90,θ3=θ+135,θ 12 =θ+180,θ 13 =θ+225,θ 14 =θ+270,θ 15 =θ+315;γ i is the north-seeking value of the ith position among the 16 positions obtained in step 5.

1.

6. The automated calibration method for a vehicle-mounted laser inertial system according to claim 5, characterized in that: In step 5.2, the heading effect deviation value Δ is calculated according to the following formula: Δ=3600*∑Δ i / 16.

7. The automated calibration method for a vehicle-mounted laser inertial system according to claim 1, characterized in that: The static bearing keeping accuracy is determined according to the following formula: γ = |γ1′-γ2′|; Where γ1′ is the heading angle measurement value of the laser inertial system on the vehicle to be inspected at the current moment, read 1 minute after the north-seeking is completed; γ2′ is the heading angle measurement value of the laser inertial system on the vehicle to be inspected at the current moment, read another 1 hour later.

8. An automated calibration and testing system for a vehicle-mounted laser inertial system, characterized by: The method comprises a memory and a processor, wherein the memory stores a computer program, and when the computer program is executed by the processor, the process of steps 3 to 6 in the automatic calibration method of the vehicle-mounted laser inertial system according to any one of claims 1 to 7 is implemented.

9. A computer-readable storage medium, characterized in that: A computer program is stored thereon, and when the computer program is executed, the process of steps 3 to 6 in the automatic calibration method of the vehicle-mounted laser inertial system according to any one of claims 1 to 7 is implemented.

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