Laser radar calibration device

Abstract

The utility model relates to a laser radar calibration device comprising a test main body, and the interior of the test main body comprises a first installation position and a second installation position. The first installation position is provided with a first laser radar to be calibrated, and the second installation position is provided with a second laser radar which completes calibration. The target plate and the test main body are oppositely arranged in a first direction; the displacement module comprises a slide rail, and the test main body and the target plate can move along the slide rail; the control module comprises an upper computer and a displacement controller; the receiving end of the upper computer is connected with the first laser radar and the second laser radar, and the output end is connected with the displacement controller which is used for controlling the distance between the test body and the target plate in the first direction. According to the utility model, the laser radar can be immediately driven to move to the next distance measurement position after one-time data collection, so that the calibration efficiency is improved; compared with the manual control of the movement of the laser radar or the target plate, the position of the light spot does not need to be recalibrated when the position is changed, and the calibration precision and accuracy are better.

Description

Technical Field

[0001] The utility model relates to the technical field of laser radar calibration, in particular to a laser radar calibration device. Background Art

[0002] LiDAR is a radar system that emits laser beams to detect target position, speed and other characteristic quantities. It emits a detection laser beam to the target, receives the signal reflected from the target, compares it with the transmitted signal, and obtains relevant information such as the target's distance, direction, and altitude. LiDAR is widely used in geographic surveying and mapping, autonomous driving and other fields due to its high precision and high resolution.

[0003] To ensure measurement accuracy, the laser radar needs to be calibrated before leaving the factory, and a target plate is set to reflect the laser beam. In the existing calibration process, the position of the target plate is manually set and adjusted. Each calibration requires moving the target plate once, observing and collecting the position information of the light spot on the target surface, and keeping the light spot position unchanged for manual alignment. The labor cost is high and affects the calibration efficiency. Utility Model Content

[0004] To this end, the technical problem to be solved by the utility model is to overcome the technical difficulty in the prior art that manual adjustment of the target surface position during laser radar calibration affects the calibration efficiency and accuracy, and to provide a laser radar calibration device to achieve automatic control during the calibration process and improve the calibration efficiency.

[0005] In order to solve the above technical problems, the utility model provides a laser radar calibration device, which includes:

[0006] A test body, wherein the test body includes a first installation position and a second installation position; the first installation position is provided with a first laser radar to be calibrated, and the second installation position is provided with a second laser radar that has completed calibration;

[0007] A target plate, wherein the target plate and the test subject are arranged opposite to each other in a first direction;

[0008] A displacement module, wherein the displacement module comprises a slide rail, wherein the slide rail extends along the first direction; the test body and the target plate are capable of moving along the slide rail;

[0009] A control module, the control module includes a host computer and a displacement controller; a receiving end of the host computer is connected to the first laser radar and the second laser radar, and an output end of the host computer is connected to the displacement controller, and the displacement controller is used to control the distance between the test body and the target plate in the first direction.

[0010] In one embodiment of the utility model, a first slider is provided at the bottom of the test body and is slidably connected to the slide rail, and a second slider is provided at the bottom of the target plate and is slidably connected to the slide rail; at least one of the first slider and the second slider is configured to be fixed in the first direction.

[0011] In one embodiment of the present invention, the slide rail includes a first rail and a second rail arranged in parallel, the first rail and the second rail are spaced apart in a second direction, and the second direction is perpendicular to the first direction.

[0012] In one embodiment of the utility model, the slide rail also includes a connecting beam and an adjustment block; the connecting beam is located in the interval and connects the first track and the second track along the second direction, and the adjustment block is located on the side of the first track and the second track away from the interval in the second direction.

[0013] In one embodiment of the present invention, the displacement module further includes a rack and a gear. The rack has two groups. The two groups of racks are located in the interval and are respectively arranged close to the first track and the second track. The gear has a tooth surface meshing with the rack.

[0014] In one embodiment of the present utility model, the control module includes a servo motor, which drives the gear to rotate; the displacement controller is configured as a motor controller, which is connected to and controls the start and stop of the servo motor.

[0015] In one embodiment of the utility model, one side surface of the target plate in the thickness direction is set as a reflective surface, and the reflective surface is perpendicular to the first direction; the first laser radar and the second laser radar both emit laser beams along the first direction and toward the reflective surface.

[0016] In one embodiment of the present invention, the first installation position and the second installation position are arranged along a vertical direction inside the test body.

[0017] In an embodiment of the present invention, the target plate is made of stainless steel.

[0018] In one embodiment of the present invention, the host computer is configured as a PC.

[0019] The above technical solution of the utility model has the following beneficial effects compared with the prior art:

[0020] The laser radar calibration device described in the utility model can realize the cyclic driving of the laser radar, and thus realize its ranging at multiple positions; on the one hand, it reduces the waiting time between different positions, and can immediately drive the laser radar to move to the next ranging position after completing one data collection; the automation degree of the device and the calibration efficiency are improved; on the other hand, compared with manually controlling the movement of the laser radar or the target plate, it has higher stability, and there is no need to recalibrate the spot position when changing position, and the calibration precision and accuracy are better. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to make the content of the utility model easier to understand, the utility model is further described in detail according to the specific embodiments of the utility model in combination with the accompanying drawings, wherein:

[0022] Figure 1 This is a schematic diagram of the structure of a laser radar calibration device in a preferred embodiment of the utility model;

[0023] Figure 2 This is a schematic diagram of the principle of the laser radar calibration device in the preferred embodiment of the utility model;

[0024] Figure 3 It is a working schematic diagram of the control module in the preferred embodiment of the utility model.

[0025] Explanation of the reference numerals in the specification: 1. Test body; 11. First mounting position; 12. Second mounting position; 2. Target plate; 21. Reflection surface; 3. Slide rail; 31. First track; 32. Second track; 33. Connecting beam; 34. Adjustment block; 4. Host computer; 5. Displacement controller; 6. Servo motor. DETAILED DESCRIPTION

[0026] The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments so that those skilled in the art can better understand the present invention and implement it, but the embodiments are not intended to limit the present invention.

[0027] Example

[0028] Reference Figure 1 to Figure 3 As shown, the utility model provides a laser radar calibration device, which includes a test body 1, a target plate 2, a displacement module and a control module; the position adjustment of the test body 1 or the target plate 2 during the calibration process is realized through the control module, thereby avoiding continuous calibration of the spot position during manual adjustment, and improving the calibration efficiency and accuracy.

[0029] Specifically, refer to Figure 1As shown, the test body 1 is provided with a laser radar to be calibrated, and the target plate 2 is arranged opposite to the test body 1 in the first direction; one side surface of the target plate 2 in the thickness direction is set as a reflective surface 21, and the reflective surface 21 is perpendicular to the first direction; the laser radar emits laser to the reflective surface 21, and the laser reflected back by the reflective surface 21 is received by the laser radar again, and the distance between the laser radar and the reflective surface 21 is calculated according to the time difference between the emission and the incidence. In some embodiments, at least the material of the reflective surface 21 is set to stainless steel to maintain the reflective performance and improve the ranging accuracy; in other embodiments, the reflective surface 21 can also be set to glass, plastic, or metal coated with reflective material.

[0030] Next, it should be noted that the test body 1 includes a first installation position 11 and a second installation position 12. The first installation position 11 is provided with a first laser radar to be calibrated, and the first laser radar is set as the laser radar to be calibrated. The second installation position 12 is provided with a second laser radar, which is a calibrated laser radar. The second laser radar serves as a standard ranging module to form a ranging control of the first laser radar, so as to calibrate and calibrate the first laser radar.

[0031] Next, the first laser radar and the second laser radar both emit laser beams along the first direction and toward the reflecting surface 21 to obtain a first ranging result; after changing the distance between the test body 1 and the target plate 2, the relative moving distances between the first laser radar and the second laser radar and the target plate 2 are equal, and a second ranging result is obtained at this time, and the difference between the first ranging result and the second ranging result is the moving distance measured by the laser radar; if the difference between the moving distance obtained by the first laser radar and the moving distance obtained by the second laser radar is within the error range, the first laser radar completes the calibration. In a preferred embodiment of the utility model, by comparing the moving distance, compared with comparing the ranging results, the ranging error caused by the position difference of the first laser radar and the second laser radar in the first direction can be avoided, and only the first laser radar and the second laser radar need to form the same relative moving distance, without considering the specific placement positions of the first laser radar and the second laser radar, which is more efficient when assembling the calibration device and the calibration result is more accurate. In some embodiments, the first mounting position 11 and the second mounting position 12 are arranged in the vertical direction inside the test body 1.

[0032] Specifically, refer to Figure 1As shown, the displacement module includes a slide rail 3, the slide rail 3 extends along the first direction, and the test body 1 and the target plate 2 can move along the slide rail 3; further, a first slider is provided at the bottom of the test body 1 to be slidably connected to the slide rail 3, and a second slider is provided at the bottom of the target plate 2 to be slidably connected to the slide rail 3; at least one of the first slider and the second slider is configured to be fixed in the first direction. In some embodiments, the position of the first slider is fixed, and the second slider slides to change the position of the target plate 2, thereby changing the distance between the reflective surface 21 and the laser radar; in some embodiments, the position of the second slider is fixed, and the first slider slides to change the position of the test body 1, thereby changing the distance between the reflective surface 21 and the laser radar.

[0033] Further, the slide rail 3 includes a first rail 31 and a second rail 32 arranged in parallel, the first rail 31 and the second rail 32 have a gap in a second direction, and the second direction is perpendicular to the first direction; the slide rail 3 also includes a connecting beam 33 and an adjustment block 34; the connecting beam 33 is located in the gap and connects the first rail 31 and the second rail 32 along the second direction, and the adjustment block 34 is located on the side of the first rail 31 and the second rail 32 away from the gap in the second direction, and is used to fix the rails and adjust the gap width in the second direction.

[0034] Furthermore, the displacement module also includes a rack and a gear, and there are two groups of racks. The two groups of racks are located in the interval and are respectively arranged close to the first track 31 and the second track 32, and the gear has a tooth surface meshing with the rack; in a preferred embodiment of the utility model, the gear is fixed at the bottom of the test body 1, and the test body 1 moves along the first direction during the meshing transmission process between the gear and the rack, and the position of the target plate 2 in the first direction is fixed for calibration.

[0035] Specifically, the laser radar calibration device realizes automatic control and calibration of the test subject 1 through the control module; Figure 3As shown, the control module includes a host computer 4, a displacement controller 5 and a servo motor; the receiving end of the host computer 4 is connected to the first laser radar and the second laser radar to receive their ranging results, and the output end of the host computer 4 is connected to the displacement controller 5. After receiving the ranging result data once, the host computer 4 controls the displacement controller 5 to perform the next ranging, and the displacement controller 5 is used to control the distance between the test body 1 and the target plate 2 in the first direction. In some embodiments, the host computer 4 is set as a PC; the displacement controller 5 is set as a motor controller, the gear of the displacement module is driven by a servo motor, and the displacement controller 5 is connected to and controls the start and stop of the servo motor.

[0036] It should be noted that, through research by the inventors of this case, it was found that in the existing calibration process, scales are marked on the guide rails on which the laser radar or target plate 2 moves, and the moving distance of the laser radar is read through the scales and compared with the ranging results for calibration; on the one hand, when transmission is performed through the meshing of gears and racks, the minimum step length of the movement of the test subject 1 is related to the tooth surface parameters, and the ideal stepless adjustment cannot be fully achieved. Therefore, it is difficult for the position of the laser radar to correspond to the scale lines, and there is an order of magnitude difference between the accuracy of the gears and the scale setting of the track, and there is a large error in the calibration using the scale line readings; on the other hand, even if the moving distance is set by the other driving devices to adjust the position of the test subject 1, there is still a certain deviation between the preset adjustment distance and the actual moving distance of the test subject 1. Therefore, the track scale lines are not suitable for the calibration of the laser radar, which affects the calibration and detection accuracy. In the preferred embodiment of the utility model, by setting the second laser radar as the standard ranging module, and using the change in the relative distance between the two groups of laser radars and the target plate 2 during movement as the calibration data, it is possible to eliminate the scale setting of the slide rail 3, reduce costs and simplify the device structure, and compensate for the deviation of the moving distance, thereby improving the calibration precision and accuracy.

[0037] The working principle of the laser radar calibration device described in the utility model is as follows:

[0038] Reference Figure 3 As shown, the host computer 4 sends a movement instruction to the displacement controller 5. After receiving the movement instruction, the displacement controller 5 adjusts the speed and number of revolutions of the servo motor, and moves the test body 1 along the slide rail 3 through the engagement of the gear and the rack; after the test body 1 reaches the preset first ranging position, the host computer 4 sends a ranging instruction to the first laser radar and the second laser radar, and the first laser radar and the second laser radar measure the distance between themselves and the reflective surface 21 of the target plate 2, and send a ranging result back to the host computer 4 to complete its measurement at the first ranging position.

[0039] After receiving the returned data, the host computer 4 repeats the above steps to move the laser radar to the preset second ranging position to complete the measurement of the second ranging position until all preset positions are tested; compare the difference between the ranging results of the first laser radar and the second laser radar to determine whether the calibration is completed.

[0040] Obviously, the above embodiments are merely examples for the purpose of clear explanation and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived therefrom are still within the scope of protection of the invention of the utility model.

Claims

1. A laser radar calibration device, characterized in that: include, A test body, wherein the test body includes a first installation position and a second installation position; the first installation position is provided with a first laser radar to be calibrated, and the second installation position is provided with a second laser radar that has completed calibration; A target plate, wherein the target plate and the test subject are arranged opposite to each other in a first direction; A displacement module, wherein the displacement module comprises a slide rail, wherein the slide rail extends along the first direction; the test body and the target plate are capable of moving along the slide rail; A control module, the control module includes a host computer and a displacement controller; a receiving end of the host computer is connected to the first laser radar and the second laser radar, and an output end of the host computer is connected to the displacement controller, and the displacement controller is used to control the distance between the test body and the target plate in the first direction.

2. A laser radar calibration device according to claim 1, characterized in that: A first slider is provided at the bottom of the test body and is slidably connected to the slide rail, and a second slider is provided at the bottom of the target plate and is slidably connected to the slide rail; at least one of the first slider and the second slider is configured to be fixed in the first direction.

3. A laser radar calibration device according to claim 1, characterized in that: The slide rail includes a first rail and a second rail arranged in parallel, the first rail and the second rail are spaced apart in a second direction, and the second direction is perpendicular to the first direction.

4. A laser radar calibration device according to claim 3, characterized in that: The slide rail further includes a connecting beam and an adjusting block; the connecting beam is located in the interval and connects the first track and the second track along the second direction, and the adjusting block is located on a side of the first track and the second track away from the interval in the second direction.

5. A laser radar calibration device according to claim 3, characterized in that: The displacement module also includes a rack and a gear. The rack has two groups. The two groups of racks are located in the interval and are respectively arranged close to the first track and the second track. The gear has a tooth surface meshing with the rack.

6. A laser radar calibration device according to claim 5, characterized in that: The control module includes a servo motor, which drives the gear to rotate; the displacement controller is configured as a motor controller, which is connected to and controls the start and stop of the servo motor.

7. The laser radar calibration device according to claim 1, characterized in that: One side surface of the target plate in the thickness direction is set as a reflection surface, and the reflection surface is perpendicular to the first direction; the first laser radar and the second laser radar both emit laser beams along the first direction and toward the reflection surface.

8. A laser radar calibration device according to claim 7, characterized in that: The first installation position and the second installation position are arranged along a vertical direction inside the test body.

9. The laser radar calibration device according to claim 1, characterized in that: The material of the target plate is set to stainless steel.

10. The laser radar calibration device according to claim 1, characterized in that: The host computer is set to be a PC.

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