Distance measurement calibration equipment and distance measurement calibration method

Abstract

The invention provides distance measurement calibration equipment and a distance measurement calibration method, the distance measurement calibration equipment comprises a base, a power module, an electric control module and a calibration module, and the power module is arranged on the base; the electric control module is arranged on the base and is electrically connected with the power module driver; the calibration module comprises a plurality of reflecting plates, the plurality of reflecting plates are independently connected with the power module and are arranged around the central axis of the output end of the power module, and the reflectivity of each reflecting plate is different; the power module is used for driving the reflecting plates to rotate in the testing process, so that the reflecting plates are switched from the initial positions to the calibration positions one by one. The distance measurement calibration equipment provided by the invention does not need to be manually replaced, can realize arrangement of a plurality of test points, is favorable for effectively reducing the area of a test site, and realizes efficient and area-saving distance measurement calibration of the plurality of test points.

Description

Technical Field

[0001] This application belongs to the field of laser ranging technology, and more specifically relates to ranging calibration equipment and ranging calibration method. Background Technology

[0002] LiDAR is a type of ranging product. It is a radar system that detects the position, velocity, and other characteristics of a target by emitting a laser beam. It emits a laser beam towards the target and receives the signal reflected back from the target. After comparing and processing the reflected signal with the emitted signal, it obtains relevant target information. LiDAR is widely used in fields such as geographic surveying and autonomous driving due to its high precision and high resolution.

[0003] Currently, when calibrating distance measurement using lidar, signals are emitted and received at multiple distances and at test boards with different reflectivities. These signals are then processed to obtain standard distance measurement parameters. During the testing process, the test boards with different reflectivities are mostly switched manually, which is labor-intensive and inefficient. Therefore, there is an urgent need to develop a distance measurement device that can automatically switch test boards to efficiently achieve distance measurement calibration at multiple test points. Summary of the Invention

[0004] The first objective of this application is to provide a ranging calibration device to solve the technical problem in the prior art where test plates with different reflectivities are mostly switched manually during the testing process, which is labor-intensive and inefficient.

[0005] The second objective of this application is to provide a distance measurement calibration method for applying the aforementioned distance measurement calibration equipment to distance measurement products.

[0006] To achieve the above objectives, the technical solution adopted in this application is as follows: A ranging calibration device is provided, comprising: Base; The power module is mounted on the base; The calibration module includes multiple reflectors, each connected to the power module and arranged around the central axis of the power module's output end. Each reflector has a different reflectivity. An electronic control module is mounted on the base and electrically connected to the power module. The electronic control module is used to control the power module to drive the reflectors to rotate sequentially during testing, switching each reflector to a calibration position.

[0007] Optionally, the reflector has an initial position before calibration, a calibration position for receiving incident light, and a waiting position after calibration. All the calibration positions of the reflectors are the same. During the test, the electronic control module controls the power module to drive the reflectors to rotate sequentially, switching each reflector from the initial position to the calibration position to complete the calibration, and then rotating it to the waiting position.

[0008] Optionally, the base is provided with a limiting structure, which is at least partially located at the calibration position; the calibration module also includes multiple switches, one of which is correspondingly disposed on one of the reflectors, and the multiple switches are independently electrically connected to the electronic control module; when the reflector moves to the calibration position, the switch and the limiting structure are positioned and engaged.

[0009] Optionally, the limiting structure is provided with a groove, and the switch has a retractable locking post. When the reflector is rotated to the calibrated position, the retractable locking post is inserted into the groove.

[0010] Optionally, there may be multiple grooves, the number of grooves may be greater than or equal to the number of reflectors, the groove closest to the reflector is located at the calibration position, and the remaining grooves are located at the waiting position.

[0011] Optionally, the plurality of grooves are arranged in an arc shape along the movement trajectory of the reflector.

[0012] Optionally, two adjacent grooves form an angle β with the vertical line connecting them to the central axis of the power module output terminal, wherein the angle β is 5°-15°; and / or, The included angle θ between two adjacent reflectors is 5°-15°.

[0013] Optionally, the reflectivity of the reflector increases in either a counter-clockwise or clockwise direction; and / or, The reflectivity of the reflector is 5%-80%.

[0014] Optionally, the power module (20) includes a driver, a rotating shaft, and several clutch units. The driver is mounted on the base. The rotating shaft is connected to the driver. Each clutch unit is mounted on the rotating shaft and arranged sequentially along the axis of the rotating shaft. The number of clutch units and the number of reflectors are equal and they are connected in a one-to-one correspondence. Each clutch unit is electrically connected to the electronic control module and is used to disconnect from or connect to the rotating shaft under the control of the electronic control module.

[0015] Optionally, the clutch unit includes a clutch fitted on the rotating shaft and a clutch adapter plate connecting the clutch and the reflector; the clutch is electrically connected to the electronic control module.

[0016] Optionally, the power module further includes several bearing assemblies and several bearing adapter plates, with one bearing assembly correspondingly connected to one bearing adapter plate, and each bearing adapter plate correspondingly connected to the reflector.

[0017] A ranging calibration method, wherein the ranging calibration device described above is used for ranging of a ranging product, includes the following steps: Select a placement location and install the ranging product at the designated location; When the preset parameters are input into the electronic control module, all the reflectors are in their initial positions. The power module is controlled by the electronic control module to drive the first reflector to rotate to the calibrated position. The ranging product emits a laser signal to the reflector, the reflector receives the laser signal and feeds it back to the electronic control module as a feedback signal, the laser signal is reflected by the reflector back to the ranging product, and the ranging product collects the first calibration data; After the first measurement is completed, the electronic control module receives a feedback signal and controls the power module to drive the first reflector to rotate away from the calibration position; Repeat the calibration steps of the first emission plate for the remaining reflectors to obtain the remaining calibration data in sequence; The calibration data is fitted to obtain correction coefficients for improving the ranging accuracy of the ranging product. These correction coefficients are then input into the ranging model formula of the ranging product.

[0018] Optionally, the ranging model formula is: y = x1 + ax1 + bx2 + c; In the formula, y is the corrected distance; x1 is the measured distance; x2 is the laser intensity; a is the distance coefficient; b is the laser intensity coefficient; and c is a constant. In the fitting process based on the obtained calibration data, a, b, and c in the ranging calibration model formula are dynamically corrected, and the corrected a, b, and c are the correction coefficients.

[0019] The beneficial effects of the ranging calibration equipment and ranging calibration method provided in this application are as follows: Compared with the prior art, the ranging calibration device of this application has multiple reflective plates with different reflectivities. The multiple reflective plates are arranged in a ring around the central axis of the output end of the power module. The power module drives the reflective plates to rotate, realizing the automatic switching of multiple reflective plates with different reflectivities. The calibration positions of multiple reflective plates are consistent. After the first reflective plate is tested, the second reflective plate can be switched. This cycle is repeated without manual replacement. Furthermore, the rotation of the reflective plates is circumferential with the central axis of the power module as the central axis. The calibration position of each reflective plate is consistent, and multiple test points can be arranged. By moving the entire ranging calibration device, ranging calibration can be realized at each of the arranged test points. This can effectively save the area of ​​the test site and realize efficient and space-saving ranging calibration of multiple test points. The distance measurement calibration method of this application, when the distance measurement calibration equipment of this application is applied to distance measurement of distance measurement products, can realize the automatic switching of multiple reflective plates with different reflectivities, and efficiently and accurately realize the distance measurement calibration of multiple test points, saving manpower and material resources. Attached Figure Description

[0020] To more clearly illustrate the technical solutions in the embodiments of this application, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0021] Figure 1 This is a schematic diagram of the structure of the ranging calibration device provided in the embodiments of this application; Figure 2 for Figure 1 A top view of the distance measuring calibration device shown; Figure 3 for Figure 2 An enlarged schematic diagram of part A in the middle; Figure 4 for Figure 1 The diagram shows the application of the ranging calibration equipment. Figure 5 for Figure 2 A schematic diagram illustrating the application of the first reflector plate calibration in a ranging calibration device; Figure 6 for Figure 2 A schematic diagram illustrating the application of the second reflector calibration in a ranging calibration device; Figure 7 for Figure 2 A schematic diagram illustrating the application of the third reflector calibration in a ranging calibration device; Figure 8 for Figure 2 A schematic diagram illustrating the application of the fourth reflector plate in the ranging calibration equipment.

[0022] The following are the labeling elements in the figure: 1. Distance measuring calibration equipment; 10. Base; 11. Frame; 12. Support plate; 13. Foot cup; 14. Pulley; 15. Limiting structure; 151. Groove; 1511. First groove; 1512. Second groove; 1513. Third groove; 1514. Fourth groove; 20. Power module; 21. Driver; 22. Transmission unit; 221. Reducer; 222. Coupling; 223. Shaft mounting plate; 24. Rotary shaft; 25. Clutch unit; 26. Electric clutch; 27. Clutch adapter plate; 28. Bearing assembly; 29. ​​Bearing adapter plate; 210. Shaft fixing plate; 30. Electronic control module; 40. Calibration module; 41. Reflector; 411. First reflector; 412. Second reflector; 413. Third reflector; 414. Fourth reflector; 42. Switch. Detailed Implementation

[0023] To make the technical problems, technical solutions, and beneficial effects to be solved by this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and are not intended to limit the scope of this application.

[0024] It should be noted that when a component is referred to as being "fixed to" or "set on" another component, it can be directly on or indirectly on that other component. When a component is referred to as being "connected to" another component, it can be directly connected to or indirectly connected to that other component.

[0025] It should be understood that the terms "length", "width", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", and "outer" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0026] 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 one or more of that feature. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.

[0027] Please refer to the following: Figure 1 and Figure 2 The ranging calibration device 1 provided in the embodiments of this application will now be described. The ranging calibration device 1 includes a base 10, a power module 20, an electronic control module 30, and a calibration module 40; the power module 20 and the electronic control module 30 are both disposed on the base 10; the electronic control module 30 is electrically connected to the power module 20.

[0028] The calibration module 40 includes multiple reflectors 41, which are independently connected to the power module 20 and arranged around the central axis of the output end of the power module 20. Each reflector 41 has a different reflectivity.

[0029] The electronic control module 30 is used to control the power module 20 to drive the reflector 41 to rotate sequentially during the test, and to switch the reflector 41 to the calibration position one by one.

[0030] Compared with the prior art, the ranging calibration device 1 of this application has multiple reflective plates 41 with different reflectivities. The multiple reflective plates 41 are arranged around the central axis of the output end of the power module 20. The power module 20 drives the reflective plates 41 to rotate sequentially, realizing automatic switching of multiple reflective plates 41 with different reflectivities. The calibration positions of multiple reflective plates 41 are consistent. When the previous reflective plate 41 has been tested, the next reflective plate 41 can be switched. This cycle is repeated without manual replacement. Furthermore, the rotation of the reflective plates 41 moves around the central axis of the output end of the power module 20. Since the calibration position of each reflective plate 41 is consistent, there is no interference between the reflective plates. Therefore, multiple test points can be arranged. By moving the entire ranging calibration device 1, ranging calibration of each arranged test point can be realized, which can effectively save the area of ​​the test site and realize efficient and space-saving ranging calibration of multiple test points.

[0031] In some embodiments, the reflector 41 has an initial position, a calibration position, and a waiting position. The initial position is the position where the reflector 41 is before calibration. The calibration position is the position where the reflector 41 receives incident light. All reflectors 41 have the same calibration position. The waiting position is the position where the reflector 41 waits after calibration. During the test, the power module 20 is controlled by the electronic control module 30 to drive the reflector 41 to rotate sequentially, so that the reflector 41 rotates from the initial position to the calibration position one by one. After calibration, it rotates from the calibration position to the waiting position.

[0032] It should be noted that the initial position and the waiting position refer to the initial and final points of the trajectory of a reflector 41 during a single ranging calibration process, respectively. The initial position and the waiting position are located on either side of the calibration position. Since the reflector 41 is a solid structure, it occupies a certain amount of space, so the initial position and the waiting position of each reflector 41 are different. In some special cases, the calibration position and the waiting position of the last reflector 41 overlap; that is, after the last reflector 41 completes the calibration test, it does not leave the calibration position and uses the calibration position as its waiting position.

[0033] The base 10 provides a mounting foundation for the power module 20, the electronic control module 30, and the calibration module 40, enabling all components to be assembled into a complete device.

[0034] In some embodiments, the base 10 includes a frame 11 and a support plate 12. The support plate 12 is vertically disposed on the frame 11, and the electronic control module 30 is installed in the frame 11. The support plate 12 is used to install the power module 20, so that multiple components of the power module 20 can be installed along the extension direction of the support plate 12.

[0035] In some embodiments, the base 10 further includes feet 13 and pulleys 14. Both feet 13 and pulleys 14 are mounted on the bottom of the frame 11. The feet 13 are used after the ranging calibration device 1 has been positioned, providing support and stability. The pulleys 14 are used when moving the ranging calibration device 1, facilitating movement and handling. Optionally, the pulleys 14 can be casters, facilitating movement in multiple directions.

[0036] The reflector 41 has a photosensitive structure electrically connected to the electronic control module 30. The photosensitive structure is used to sense the light incident on the reflector 41 and, after sensing the light, sends the photosensitive information to the electronic control module 30. After receiving the photosensitive information, the electronic control module 30 controls the power module 20 to drive the reflector 41, which has received the light, to rotate.

[0037] In some embodiments, the base 10 is provided with a limiting structure 15, which is at least partially located at the calibration position. This limiting structure 15 is used to position the reflector 41 at the calibration position, ensuring that the reflector 41, when moved to the calibration position, will not move during calibration, thus guaranteeing the accuracy of the obtained calibration data. At this time, the calibration module 40 also includes multiple switches 42, each switch 42 corresponding to a reflector 41. Each switch 42 is independently electrically connected to the electronic control module 30. Through commands from the electronic control module 30, the reflector 41 can be sequentially driven to establish a connection with the power module 20, and the connection between the reflector 41 and the power module 20 can be switched.

[0038] When the first reflector 41 needs to rotate, the electronic control module 30 drives the switch 42 on the first reflector 41 to activate, causing the power module 20 to switch to a state where it can connect with the first reflector 41. In this way, the power module 20 can drive the first reflector 41 to rotate. When the reflector 41 rotates to the waiting position, the module controls the switch 42 on the first reflector 41 to activate again, disconnecting the power module 20 from the reflector 41. When the remaining reflectors 41 need to rotate in sequence, the electronic control module 30 controls the corresponding switches 42 of the remaining reflectors 41 to activate, causing the power module 20 to drive the remaining reflectors 41 to switch to a state where they can connect in sequence. This allows the power module 20 to drive the remaining reflectors 41 to rotate in sequence under the control of the electronic control module 30. When the reflector 41 moves to the calibrated position, the switch 42 engages with the limiting structure 15. When the reflector 41 receives light, the photosensitive structure of the emitter 41 sends the photosensitive information to the electronic control module 30. The electronic control module 30 controls the power module 20 to drive the emitter 41 to rotate to the waiting position, and the switch 42 separates from the limiting structure 15.

[0039] In some embodiments, the switch limiting structure 15 is provided with a groove 151, and the switch 42 has a retractable locking post. When the reflector 41 is rotated to the calibration position, the retractable locking post is inserted into the groove 151. In use, when the reflector 41 moves to the calibration position, the retractable locking post engages in the groove 151, which serves as a limit to prevent the reflector 41 from shifting during calibration and affecting the accuracy of the measurement results. On the other hand, the cooperation between the groove 151 and the retractable locking post also ensures the consistency of each reflector 41 in the calibration position, reducing calibration error.

[0040] In other embodiments, the switch 42 is provided with a structure of a miniature electric cylinder with a telescopic rod. The miniature electric cylinder is electrically connected to the electronic control module 30. The extension and retraction of the telescopic rod are controlled by the electronic control module 30. The telescopic rod of the miniature electric cylinder is a telescopic locking pin.

[0041] In some embodiments, there are multiple grooves 151, and the number of grooves 151 is greater than or equal to the number of reflectors 41. When all reflectors 41 are in the initial position, the groove 151 closest to the reflector 41 is in the calibration position, and the remaining grooves 151 are in the waiting position. Therefore, when the reflector 41 moves to the waiting position, the switch 42 on the reflector 41 is also inserted into the groove 151 in the waiting position. Specifically, the switch 42 on the first reflector 41 is inserted into the groove 151 farthest from the calibration position, and the remaining grooves 151 in the waiting position are sequentially inserted by the switch 42 on the subsequent reflectors 41 in the order opposite to the rotation direction of the reflector 41. The groove 151 is concave and the groove wall is arc-shaped. The locking post is telescopic, which facilitates the insertion and sliding out of the groove 151.

[0042] In some embodiments, multiple grooves 151 are arranged in an arc along the movement trajectory of the reflector 41, which facilitates the easy installation of the retractable pin and the positioning of the retractable pin with the grooves 151.

[0043] The power module 20 includes a driver 21 for driving the reflector 41 to rotate. The driver 21 is fixed on the base 10. All the reflectors are distributed in a ring around the central axis of the output end of the driver 21. Therefore, the axis of rotation is the central axis of the output end of the driver 21. The angle β formed by the perpendicular line connecting two adjacent grooves 151 to the central axis of the output end of the driver 21 is 5°-15°. This arrangement can save movement space and movement energy. After the multiple reflectors 41 are respectively positioned in the grooves 151, the two adjacent reflectors 41 will not be damaged due to friction.

[0044] The power module 20 provides power for the movement of the calibration module 40, mainly for the movement of the reflector 41. Optionally, the driver 21 can be a motor.

[0045] In some embodiments, such as Figure 1 As shown, optionally, as Figure 3 As shown, the power module 20 also includes a rotating shaft 24 and several clutch units 25. One end of the rotating shaft 24 is connected to the driver 21, and the other end is rotatably connected to the shaft fixing plate 210 for rotation under the drive of the driver 21. Each clutch unit 25 is mounted on the rotating shaft 24 and arranged sequentially along the axis of the rotating shaft 24. The number of clutch units 25 and reflectors 41 is equal and they are connected one-to-one. Each clutch unit 25 is electrically connected to the electronic control module 30 through the switch 42 on the corresponding reflector 41, and is used to switch to a state of being disconnected from the rotating shaft 24 or a state of being connected to the rotating shaft 24 under the control of the electronic control module 30. For example, when the first reflector 411 is to be driven to rotate, the electronic control module 30 controls the switch 42 on the first reflector 411 to activate, causing the clutch unit 25 corresponding to the first reflector 411 to switch to a state connected to the rotating shaft 24. Then, the driver 21 can be controlled to drive the rotating shaft 24 to rotate the first reflector 411. When the first reflector 411 rotates to its corresponding waiting position, the electronic control module 30 controls the switch 42 on the first reflector 411 to activate, causing the clutch unit 25 on the first reflector 411 to switch to a state disconnected from the rotating shaft 24. In this way, when the electronic control module 30 controls the power module 20 to drive the second reflector 412 to rotate, the first reflector 411 can still remain at its corresponding waiting position and will not rotate away from its corresponding waiting position along with the second reflector 412. Subsequent reflectors 41 perform the above operation, thereby ensuring that each reflector 41 can move to its corresponding waiting position after calibration.

[0046] Furthermore, the driver 21 is connected to the rotating shaft 24 via a transmission unit 22. Specifically, the transmission unit 22 includes a shaft mounting plate 223, a reducer 221, and a coupling 222. The shaft mounting plate 223 is mounted on the base 10. The reducer 221 connects the driver 21 and the coupling 222. The rotating shaft 24 passes through the shaft mounting plate 223 and is connected to the coupling 222. The driver 21 is preferably a motor. After the driver 21 operates, the driving force is transmitted to the rotating shaft 24 through the reducer 221 and the coupling 222, driving the rotating shaft 24 to rotate. When the speed of the driver 21 is too high, its torque is too low, which may make it difficult to drive the reflector 41 to rotate. Adding the reducer 221 can adjust the speed, thereby adjusting the torque and smoothly driving the reflector 41 to rotate.

[0047] The clutch unit 25 includes an electric clutch 26 sleeved on a rotating shaft 24 and a clutch adapter plate 27 connecting the electric clutch 26 and the reflector plate 41; the electric clutch 26 is electrically connected to the electronic control module 30. Each electric clutch 26 and clutch adapter plate 27 is connected to a corresponding reflector plate 41. The electronic control module 30 independently controls the start and stop of one electric clutch 26 and independently controls the rotational movement of one reflector plate 41.

[0048] For example, in one scheme, the ranging calibration device 1 has three reflectors 41, and correspondingly three electric clutches 26. The first electric clutch 26 is connected to the first reflector 41, the second electric clutch 26 is connected to the second reflector 41, and the third electric clutch 26 is connected to the third reflector 41. During the calibration process, the electronic control module 30 controls the first electric clutch 26 to automatically switch to the state of being connected to the rotating shaft 24 through the switch 42 on the first reflector 41. Therefore, the first reflector 41 can rotate under the drive of the driver 21. When the first reflector 41 rotates to the waiting position, the electronic control module 30 controls the first electric clutch 26 to switch to the state of being disconnected from the rotating shaft 24 through the switch 42 on the first reflector 41. The remaining electric clutches 26 complete the subsequent rotation according to the above operation.

[0049] Understandably, the power module 20 may contain multiple electric clutches 26 and clutch adapter plates 27, the number of which is multiple times the number of reflectors 41. That is, one electric clutch 26 and one clutch adapter plate 27 can be connected to one reflector 41, or two or three electric clutches 26 and clutch adapter plates 27 can be connected to one reflector 41. The electric clutches 26 and clutch adapter plates 27 corresponding to one reflector 41 have the same motion parameters.

[0050] In some embodiments, the power module 20 further includes a plurality of bearing assemblies 28 and a plurality of bearing adapter plates 29, which are disposed on the base 10. When the base 10 includes a support plate 12, the plurality of bearing assemblies 28 and bearing adapter plates 29 are disposed on the support plate 12, with one bearing assembly 28 correspondingly connected to one bearing adapter plate 29, and the plurality of bearing adapter plates 29 respectively connected to a reflector plate 41. The bearing assemblies 28 and bearing adapter plates 29 are used in cooperation, with one side of the bearing adapter plate 29 connected to the bearing assembly 28 and the other side connected to the reflector plate 41. Each bearing assembly 28 and bearing adapter plate 29 is correspondingly connected to one reflector plate 41 for independently coordinating the movement of one reflector plate 41.

[0051] When the size of the reflector 41 is large, the resistance to the electric clutch 26 and clutch adapter plate 27 in driving the reflector 41 is large. Bearing assembly 28 and bearing adapter plate 29 can be added to reduce the motion resistance of the reflector 41. In one embodiment, such as... Figure 1 As shown, the electric clutch 26 and the clutch adapter plate 27 are connected to the middle of the reflector plate 41, and the two sets of bearing assemblies 28 and the bearing adapter plate 29 are respectively connected to the two ends of the reflector plate 41, making the rotation of the reflector plate 41 smoother.

[0052] Of course, in some implementation schemes, the connection positions of the electric clutch 26 and clutch adapter plate 27 with the reflector plate 41, as well as the connection positions and quantities of the bearing assembly 28 and bearing adapter plate 29 with the reflector plate 41, can be adjusted according to the size and structural design of the reflector plate 41. The main purpose is to make the rotation of the reflector plate 41 smoother.

[0053] Understandably, the connection between the reflector plate 41 and the clutch adapter plate 27, as well as the connection between the reflector plate 41 and the bearing adapter plate 29, can be a detachable connection for easy replacement. The detachable connection method can be screw connection, clamp connection, snap-fit ​​connection, etc.

[0054] The electronic control module 30 is a module that can input motion parameters and is used to automatically control the motion of the power module 20 and the calibration module 40.

[0055] In some embodiments, the electrical control module 30 includes a PLC (Programmable Logic Controller), a motor drive module, a circuit breaker, and a relay. The motor drive module, circuit breaker, and relay are electrically connected to the PLC. The output terminal of the motor drive module is electrically connected to the driver 21, and the output terminal of the relay is electrically connected to the switch 42.

[0056] During use, control parameters can be input to the PLC, such as the rotation speed of the driver 21, the rotation angle of the first reflector 411, and the rotation angle of the second reflector 412. The motor drive module is used to drive the driver 21 in the power module 20. An air switch is a type of circuit breaker that protects the ranging calibration device 1 from short circuits, severe overloads, and undervoltage.

[0057] When the calibration module 40 is working, the reflector 41 receives the laser signal emitted by the ranging product and feeds it back to the electronic control module 30 as a feedback signal. According to the feedback signal, the electronic control module 30 controls the power module 20 to drive the reflector 41 to rotate, so that the reflector 41 rotates from the calibration position to the waiting position. At the same time, the laser signal is reflected by the reflector 41 to the ranging product, and the ranging product collects the calibration data.

[0058] In some embodiments, the reflectivity of the reflector 41 has a certain arrangement pattern, for example, the reflectivity of the reflector 41 increases in either a counterclockwise or clockwise direction. The reflectivity of multiple reflectors 41 follows a pattern along their arrangement direction. For example, when the ranging product is emitted from the right side of the reflector 41, the reflectivity of the reflector 41 increases in a counterclockwise direction; when the ranging product is emitted from the left side of the reflector 41, the reflectivity of the reflector 41 increases in a clockwise direction, to adapt to the ranging calibration test sequence from small to large.

[0059] Depending on the calibration requirements, the reflectivity of the reflector 41 can be 5%-80%. For example, in one embodiment, the ranging calibration device 1 has three reflectors 41, with reflectivity of 5%, 45%, and 70% respectively in the counterclockwise direction; in another embodiment, the ranging calibration device 1 has four reflectors 41, with reflectivity of 5%, 15%, 60%, and 80% respectively in the counterclockwise direction; in yet another embodiment, the ranging calibration device 1 has six reflectors 41, with reflectivity of 5%, 15%, 50%, 70%, and 80% respectively in the clockwise direction; and so on.

[0060] In some embodiments, the included angle θ between two adjacent reflectors 41 is 5°-15° to distinguish each reflector 41, ensuring that the use of multiple reflectors 41 does not obstruct the use of the next reflector 41, and saving space. For example, if the number of reflectors 41 is greater than or equal to four, and after multiple reflectors are calibrated, they move sequentially to the waiting position, if the included angle θ between two adjacent reflectors 41 is greater than 15°, it will occupy a large space for the initial and waiting positions, requiring more space to be reserved for the equipment, resulting in a larger equipment size. Therefore, the included angle θ between two adjacent reflectors 41 is generally chosen to be less than or equal to 15°. To prevent friction damage between adjacent reflectors 41, the included angle θ is chosen to be at least greater than or equal to 5°.

[0061] Understandably, the included angle θ between any two adjacent reflectors 41 can be the same or different. For example, the included angle θ between the reflectors 41 may increase sequentially in a clockwise direction along the arrangement of the reflectors 41, or increase sequentially in a counterclockwise direction along the arrangement of the reflectors 41, or vary irregularly along the arrangement direction of the reflectors 41. In some preferred embodiments, the included angle θ between any two adjacent reflectors 41 is the same to facilitate control.

[0062] This application embodiment also provides a ranging calibration method, which applies the above-mentioned ranging calibration device 1 to ranging products, including the following steps: S1: Select a placement location and place the ranging product at the placement location.

[0063] In step S1, the actual distance between each test point and the placement location is measured using a total station electronic distance measuring instrument.

[0064] S2: Input the preset parameters into the electronic control module 30. At this time, all reflectors 41 are in the initial position.

[0065] S3: Control the power module 20 through the electronic control module 30 to drive the first reflector 41 to rotate to the calibration position, so that the reflective surface of the reflector 41 is perpendicular to the central axis of the target to be measured.

[0066] While controlling the operation of the power module 20, the electronic control module 30 drives the electric clutch 26 corresponding to the first reflector 41 to switch to a state where the rotating shaft 24 and the first reflector 41 can transmit power. The power module 20 drives the rotating shaft 24 to rotate, and the rotating shaft 24 drives the electric clutch 26 corresponding to the first reflector 41 to rotate. The electric clutch 26 drives the first reflector 41 to rotate, rotating the first reflector 41 to the calibration position. When the first reflector 41 is rotated to the calibration position, the electronic control module 30 controls the switch 42 to insert into the groove 151 located at the calibration position, thereby locking the first reflector 41. After that, it waits to receive the signal transmitted by the ranging product.

[0067] S4: The ranging product emits a laser signal to the reflector 41. The reflector 41 receives the laser signal and feeds it back to the electronic control module 30 as a feedback signal. The laser signal is reflected by the reflector 41 to the ranging product, and the ranging product collects the first calibration data.

[0068] S5: After the first measurement is completed, the electronic control module 30 receives a feedback signal and controls the power module 20 to drive the first reflector 41 to rotate from the calibration position to the waiting position.

[0069] After collecting the first calibration data, the first reflector 41 has completed its work and needs to leave the calibration position to prepare for the test of the second reflector 41. The driver 21 continues to rotate in the original direction of rotation, driving the electric clutch 26 corresponding to the first reflector 41 to rotate, thereby driving the first reflector 41 to rotate from the calibration position to the waiting position.

[0070] S6: Repeat the calibration operation steps of the first emission plate 41 for the remaining reflectors 41, and obtain the remaining calibration data in sequence.

[0071] Before the control module 30 controls the power module 20 to drive the next reflector 41 to rotate, it first controls the corresponding switch 42 of the next reflector 41 to operate, and controls the corresponding electric clutch 26 of the next reflector 41 to switch to the state of connecting the next reflector 41 with the rotating shaft 24, so that the driver 21 of the power module 20 can drive the reflector 41 to rotate.

[0072] S7: Fit the obtained calibration data to obtain the correction coefficients used to improve the ranging accuracy of the ranging product, and input the correction coefficients into the ranging model formula of the ranging product.

[0073] The ranging product stores the ranging model formula: y=x1+ax1+bx2+c; where y is the corrected distance; x1 is the measured distance; x2 is the laser intensity; a is the distance coefficient; b is the laser intensity coefficient; and c is a constant.

[0074] The ranging calibration device 1 and the ranging product constitute a ranging system. The ranging system also includes a central processing module, which is electrically connected to the ranging product and the electronic control module 30. The central processing module sends commands to the ranging product and the electronic control module 30, and can control the ranging product and the electronic control module 30 to respond to the commands. The ranging product emits a laser signal and then receives the laser signal reflected by the reflector 41 through its own photoelectric sensor to obtain calibration data. Then, the collected calibration data is transmitted to the central processing module in real time. The central processing module first preprocesses the data (such as noise reduction and outlier removal), and then performs data fitting on the valid calibration data to obtain the corrected correction coefficients a, b, and c.

[0075] Understandably, to obtain the values ​​of a, b, and c, the following steps are required: First, select multiple standard test points for data collection. At each test point, use a total station to measure the precise distance from the distance measuring product to the test point (i.e., the total station electronic distance measuring instrument data) and record it in the central processing module. Next, use the distance measuring product to measure each test point, obtaining multiple sets of y, x1, and x2 values. Then, subtract the distance measured by the distance measuring product from the total station data to obtain the distance measurement error of the distance measuring product to each test point. Finally, using the multiple sets of errors, the measured distance x1, and the measured laser intensity x2, etc., according to the formula error = a... x1+b The corrected a, b, and c are obtained by performing a binary linear fitting of x² + c.

[0076] The obtained correction coefficients a, b, and c are written into the non-volatile memory of the ranging product, updating its built-in ranging model y = x1 + ax1 + bx2 + c. In actual ranging scenarios, the ranging product can calculate a high-precision distance value y by collecting x1 and x2 in real time and combining them with the stored correction coefficients.

[0077] In one embodiment of the scheme, such as Figures 2 to 8 As shown, the calibration module 40 includes four reflectors 41, which are arranged in a counterclockwise direction from the side closest to the limiting structure 15, namely the first reflector 411, the second reflector 412, the third reflector 413, and the fourth reflector 414. The reflectivity of the four reflectors 41 increases in the counterclockwise direction, and are 5%, 15%, 60%, and 80%, respectively. The included angle θ between two adjacent reflectors 41 is 15°.

[0078] The limiting structure 15 has four grooves 151, which are arranged sequentially from the end closest to the reflector 41 to the end away from the reflector 41 along its arc: first groove 1511, second groove 1512, third groove 1513, and fourth groove 1514. The first groove 1511 is located at the calibration position, the fourth groove 1514 is located at the waiting position of the first reflector 411, the third groove 1513 is located at the waiting position of the second reflector 412, the second groove 1512 is located at the waiting position of the third reflector 413, and the waiting position of the fourth reflector 414 overlaps with the calibration position.

[0079] The ranging product is placed to the right of the ranging calibration device 1. During the test, the first reflector 411 rotates clockwise to the first groove 1511 (i.e., the calibration position). The retractable locking pin of the first reflector 411 is positioned in conjunction with the first groove 1511, and the first reflector 411 is vertical, perpendicular to the central axis of the target to be measured. Figure 5 As shown; After the first signal value is collected, the first reflector 411 continues to rotate 45° clockwise to the fourth groove 1514. The retractable locking pin of the first reflector 411 engages with the fourth groove 1514 for positioning. The second reflector 412 rotates clockwise to the first groove 1511 (i.e., the calibration position). The retractable locking pin of the second reflector 412 engages with the first groove 1511 for positioning. The second reflector 412 is perpendicular to the central axis of the target being measured. Figure 6 As shown; After the second signal value is collected, the second reflector 412 continues to rotate 30° clockwise to the third groove 1513. The retractable locking pin of the second reflector 412 engages with the third groove 1513 for positioning. The third reflector 413 then rotates clockwise to the first groove 1511 (i.e., the calibration position). The retractable locking pin of the third reflector 413 engages with the first groove 1511 for positioning. The third reflector 413 is perpendicular to the central axis of the target being measured. Figure 7 As shown; After the third signal value is collected, the third reflector 413 continues to rotate 15° clockwise to the second groove 1512. The retractable locking pin of the third reflector 413 is positioned in conjunction with the second groove 1512. The fourth reflector 414 rotates clockwise to the first groove 1511 (i.e., the calibration position). The retractable locking pin of the fourth reflector 414 is positioned in conjunction with the first groove 1511. The fourth reflector 414 is perpendicular to the central axis of the target to be measured. Figure 8 As shown, the fourth signal value was collected.

[0080] The four signal values ​​are substituted into the ranging model formula to calculate the distance value, and the test is completed.

[0081] The ranging calibration method of this application embodiment, when the ranging calibration device 1 of this application embodiment is applied to ranging products, can automatically switch multiple reflective plates 41 with different reflectivities to the calibration position, efficiently and accurately realize the ranging calibration of multiple test points, and save manpower and material resources.

[0082] The above description is only a preferred embodiment of this application and is not intended to limit this application. Any modifications, equivalent substitutions and improvements made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A ranging calibration device (1), characterized in that: include: Base (10); A power module (20) is disposed on the base (10); The calibration module (40) includes multiple reflectors (41), each of which is connected to the power module (20) and arranged around the central axis of the output end of the power module (20). Each reflector (41) has a different reflectivity. An electronic control module (30) is disposed on the base (10) and electrically connected to the power module (20). The electronic control module (30) is used to control the power module (20) to drive the reflector (41) to rotate sequentially during the test, and to switch the reflector (41) to the calibration position one by one.

2. The ranging calibration device (1) as described in claim 1, characterized in that: The reflector (41) has an initial position before calibration, a calibration position for receiving incident light, and a waiting position after calibration. All the reflectors (41) have the same calibration position. During the test, the electronic control module (30) controls the power module (20) to drive the reflector (41) to rotate sequentially, switching each reflector (41) from the initial position to the calibration position to complete the calibration, and then rotating it to the waiting position.

3. The ranging calibration device (1) as described in claim 2, characterized in that: The base (10) is provided with a limiting structure (15), which is at least partially located at the calibration position; the calibration module (40) also includes multiple switches (42), one of the switches (42) is correspondingly located on one of the reflectors (41), and the multiple switches (42) are independently electrically connected to the electronic control module (30); when the reflector (41) moves to the calibration position, the switch (42) and the limiting structure (15) are positioned and engaged.

4. The ranging calibration device (1) as described in claim 3, characterized in that: The limiting structure (15) is provided with a groove (151), and the switch (42) has a retractable locking post. When the reflector (41) is rotated to the calibration position, the retractable locking post is inserted into the groove (151).

5. The ranging calibration device (1) as described in claim 4, characterized in that: The number of grooves (151) is greater than or equal to the number of reflectors (41). The groove (151) closest to the reflector (41) is located at the calibration position, and the remaining grooves (151) are located at the waiting position.

6. The ranging calibration device (1) as described in claim 5, characterized in that: The plurality of grooves (151) are arranged in an arc shape along the movement trajectory of the reflector (41).

7. The ranging calibration device (1) as described in claim 6, characterized in that: The two adjacent grooves (151) form an angle β with the vertical line connecting them to the central axis of the output end of the power module (20), wherein the angle β is 5°-15°; and / or, The included angle θ between two adjacent reflectors (41) is 5°-15°.

8. The ranging calibration device (1) as described in claim 1, characterized in that: The reflectivity of the reflector (41) increases in either a counterclockwise or clockwise direction; and / or, The reflectivity of the reflector (41) is 5%-80%.

9. The ranging calibration device (1) as described in claim 1, characterized in that: The power module (20) includes a driver (21), a rotating shaft (24), and several clutch units (25). The driver (21) is mounted on the base (10). The rotating shaft (24) is connected to the driver (21). Each clutch unit (25) is mounted on the rotating shaft (24) and arranged sequentially along the axis of the rotating shaft (24). The number of clutch units (25) and the number of reflectors (41) are equal and they are connected in a corresponding manner. Each clutch unit (25) is electrically connected to the electronic control module (30) and is used to disconnect from or connect to the rotating shaft (24) under the control of the electronic control module (30).

10. The ranging calibration device (1) according to claim 9, characterized in that, The clutch unit (25) includes a clutch (26) fitted on the rotating shaft (24) and a clutch adapter plate (27) connecting the clutch (26) and the reflector plate (41); the clutch (26) is electrically connected to the electronic control module (30).

11. The ranging calibration device (1) as described in claim 1, characterized in that: The power module (20) also includes several bearing assemblies (28) and several bearing adapter plates (29), with one bearing assembly (28) and one bearing adapter plate (29) connected to each other, and the bearing adapter plate (29) and the reflector plate (41) connected to each other respectively.

12. A distance measurement calibration method, characterized in that: The ranging calibration device (1) as described in any one of claims 1-11 is used for ranging of a ranging product, comprising the following steps: Select a placement location and install the ranging product at the designated location; When the preset parameters are input into the electronic control module (30), all the reflectors (41) are in their initial positions. The power module (20) is controlled by the electronic control module (30) to drive the first reflector (41) to rotate to the calibrated position; The ranging product emits a laser signal to the reflector (41), the reflector (41) receives the laser signal and feeds it back to the electronic control module (30) as a feedback signal, the laser signal is reflected by the reflector (41) to the ranging product, and the ranging product collects the first calibration data; After the first measurement is completed, the electronic control module (30) receives a feedback signal and controls the power module (20) to drive the first reflector (41) to rotate away from the calibration position; Repeat the calibration steps of the first emission plate for the remaining reflectors (41) to obtain the remaining calibration data in sequence; The calibration data is fitted to obtain correction coefficients for improving the ranging accuracy of the ranging product. These correction coefficients are then input into the ranging model formula of the ranging product.

13. The ranging calibration method as described in claim 12, characterized in that, The distance measurement model formula is: y = x1 + ax1 + bx2 + c; In the formula, y is the corrected distance; x1 is the measured distance; x2 is the laser intensity; a is the distance coefficient; b is the laser intensity coefficient; and c is a constant. In the fitting process based on the obtained calibration data, a, b, and c in the ranging calibration model formula are dynamically corrected, and the corrected a, b, and c are the correction coefficients.

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