Method for installing and debugging scanning reflector of frequency modulation laser radar

Abstract

The invention relates to the technical field of precision measurement, in particular to a frequency modulation laser radar scanning reflector mounting and debugging method. The method comprises the following steps: starting a frequency modulation laser radar scanner, rotating a pitch axis to a 0-degree position, starting test equipment, measuring a reflecting surface of a reflector, at least measuring three non-collinear points, and scanning a reflector plane through three-point fitting; rotating a pitch axis of the frequency modulation laser radar scanner to a preset position, measuring three non-collinear points of a reflecting surface, and fitting a scanning reflecting mirror plane at the moment; analyzing the front scanning mirror plane and the rear scanning mirror plane to obtain an included angle theta, and measuring the distance SS'between the two scanning mirror planes at the pitch axis position; the included angle between the plane of the scanning reflector and the pitch axis is theta / 2, the distance is SS ' / 2, the installation plane of the reflector before and after scanning is modified, and the reflector is installed to eliminate the included angle and the distance. According to the invention, high-precision installation and debugging of the frequency modulation laser radar scanning reflector are realized, and the production efficiency and measurement precision of the frequency modulation laser radar are improved.

Description

Technical Field

[0001] This invention relates to the field of precision measurement technology, and more specifically, to a method for installing and debugging a frequency-modulated lidar scanning reflector. Background Technology

[0002] Currently, in frequency-modulated lidar measurement systems, the installation and debugging methods for scanning mirrors mainly include the following:

[0003] Low-precision systems rely on machining to ensure accuracy. This method is relatively simple, primarily ensuring the installation accuracy of the scanning mirror through the design, processing technology, and machining precision of the machining dimensional chain, and then fixing the mirror with screws. However, this method depends entirely on machining for accuracy. In actual product manufacturing, slight differences may occur between products due to variations in laser output direction and axis installation and adjustment positions. Due to the limitations of machining, errors still exist in the actual installation position of the scanning mirror relative to the azimuth and pitch axes, as well as the laser beam position. Therefore, this method can only be applied to low-precision, low-cost scanning measurement systems.

[0004] This method involves visually measuring the azimuth and pitch rotation axes, then adjusting the position of the scanning mirror until the scanning reflector surface coincides with the pitch axis. In actual scanning mirror installation, the reflecting plane of the scanning mirror is obtained visually, and the pitch axis is fitted based on the rotation relationship. The relationship between the pitch axis and the scanning mirror is then measured. If the scanning mirror and pitch axis do not coincide, the mounting base is repaired, and the measurement is repeated until the scanning mirror surface coincides with the pitch axis. However, this method, which uses visual fitting of the axis, has a certain measurement error, and the measurement and data processing process is relatively cumbersome, making it impossible to achieve high-efficiency and high-precision measurement of installation errors. Summary of the Invention

[0005] This invention aims to at least partially solve one of the technical problems in related technologies. Therefore, the objective of this invention is to propose a method for installing and debugging a frequency-modulated lidar scanning mirror. This invention achieves high-precision installation and debugging of the frequency-modulated lidar scanning mirror, improving the production efficiency and measurement accuracy of the frequency-modulated lidar.

[0006] To achieve the above and other related objectives, the present invention provides a method for installing and debugging a frequency-modulated lidar scanning reflector, comprising:

[0007] S1. The frequency-modulated lidar scanner to be debugged is installed and fixed on the workbench of the test equipment;

[0008] S2. Start the frequency-modulated lidar scanner, rotate the pitch axis to the 0° position, start the test equipment, measure the reflective surface of the reflector of the frequency-modulated lidar scanner, measure at least three non-collinear points, and fit the plane of the reflector by the three points.

[0009] S3. Rotate the pitch axis of the frequency-modulated laser radar scanner to a preset position, measure the three non-collinear points of the reflective surface again through the test equipment, and fit the scanning reflective mirror plane at this time again.

[0010] S4. Analyze the two scanning mirror planes before and after to obtain their included angle θ, and at the same time measure the distance SS' between the two scanning mirror planes at the pitch axis position;

[0011] S5. Scan the angle between the plane of the reflector and the pitch axis to θ / 2 and the distance to SS' / 2. Modify the mounting plane of the reflector before and after scanning, and reinstall the reflector to eliminate the angle and distance.

[0012] In one embodiment of the present invention, it further includes:

[0013] S6. Repeat steps S1 to S5 to obtain the angle between the two front and rear scanning mirror planes and the distance between the two scanning mirror planes at the current pitch axis position until the measured angle is not greater than the preset angle and the distance is not greater than the preset distance, then the design requirements are met.

[0014] In one embodiment of the present invention, the preset position is a 180° position.

[0015] In one embodiment of the present invention, the preset angle is 0.001°.

[0016] In one embodiment of the present invention, the preset distance is 0.01 mm.

[0017] In one embodiment of the present invention, the analysis of the front and rear scanning mirror planes in step S4 includes analyzing the front and rear scanning mirror planes through the test equipment control software.

[0018] In one embodiment of the present invention, step S5, which involves scanning the angle between the reflector plane and the pitch axis as θ / 2 and the distance as SS' / 2, includes scanning the angle between the reflector plane and the pitch axis as θ / 2 and the distance as SS' / 2 based on spatial relationships.

[0019] In one embodiment of the present invention, the testing device is a coordinate measuring machine.

[0020] As described above, the frequency-modulated lidar scanning reflector installation and debugging method of the present invention has the following beneficial effects:

[0021] The present invention discloses a method for installing and debugging a frequency-modulated lidar scanning reflector. The debugging of the frequency-modulated lidar scanning reflector is based on the rotational symmetry of the reflector surface. The mirror's pitch and tilt axes are measured and fitted before and after a 180° rotation using a coordinate measuring machine. This yields the distance and angular relationship between the pitch axis and the reflector surface. By adjusting the reflector surface, the mirror surface is made to coincide with the pitch axis. The entire debugging method does not require complicated operating procedures, and both accuracy and efficiency are greatly improved.

[0022] This invention provides a method for installing and debugging a frequency-modulated lidar scanning mirror. Using a coordinate measuring machine, and based on the principle of rotational symmetry, a portable and reliable method for installing and debugging a frequency-modulated lidar scanning mirror is established. This method achieves high-precision installation and debugging of the frequency-modulated lidar scanning mirror, thereby improving the production efficiency and measurement accuracy of the frequency-modulated lidar.

[0023] The present invention provides a method for installing and debugging a frequency-modulated lidar scanning mirror. The establishment of this method fundamentally solves the technical difficulties in the installation and debugging of frequency-modulated lidar scanning mirrors. It not only meets the requirements for high-precision debugging but also has a highly efficient operation process, which is fully adaptable to the needs of mass production. Attached Figure Description

[0024] Figure 1 This is a flowchart illustrating a method for installing and debugging a frequency-modulated lidar scanning reflector according to an embodiment of the present invention.

[0025] Figure 2 This is a schematic diagram of the measurement principle of a frequency-modulated laser radar scanner, which is an embodiment of the present invention, describing the installation and debugging method of a frequency-modulated laser radar scanning reflector.

[0026] Figure 3 This is a schematic diagram of the installation position of a frequency-modulated lidar scanning reflector installation and debugging method according to an embodiment of the present invention.

[0027] Figure 4 This is a schematic diagram of the distance measurement model between the mirror surface and the pitch axis of a frequency-modulated lidar scanning reflector installation and debugging method according to an embodiment of the present invention.

[0028] Figure 5 This is a schematic diagram of a measurement model of the angle between the mirror surface and the pitch axis in a frequency-modulated lidar scanning mirror installation and debugging method according to an embodiment of the present invention. Detailed Implementation

[0029] The following specific examples illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that, unless otherwise specified, the following embodiments and features described therein can be combined with each other.

[0030] It should be noted that the illustrations provided in the following embodiments are only schematic representations of the basic concept of the present invention. Therefore, the illustrations only show the components related to the present invention and are not drawn according to the actual number, shape and size of the components in the actual implementation. In the actual implementation, the form, quantity and proportion of each component can be arbitrarily changed, and the layout of the components may also be more complex.

[0031] Terms such as "first" or "second" may be used to describe various components, but these components are not limited by the terms described above. The terms described above are used to distinguish one component from another; for example, without departing from the scope of the concept according to this disclosure, a first component may be referred to as a second component, and similarly, a second component may be referred to as a first component.

[0032] Furthermore, "connected / linked" indicates that one component is directly electrically connected to another component or indirectly electrically connected through another component. Unless otherwise explicitly stated in the sentence, the singular form may include the plural form. Additionally, the terms "comprising / including" or "containing / including" as used in this specification indicate the presence or addition of one or more components, steps, operations, and elements. Specific structural or functional descriptions of examples of embodiments of the concepts disclosed in this specification are merely illustrative to describe examples of embodiments of the concepts, and examples of embodiments of the concepts can be implemented in various forms, but these descriptions are not limited to the examples of embodiments described in this specification.

[0033] Based on the concept, various modifications and changes can be applied to examples of embodiments, such that examples of embodiments will be illustrated in the accompanying drawings and described in the specification. However, examples of embodiments based on the concept are not limited to specific embodiments, but include all changes, equivalents, or substitutions included within the spirit and scope of this disclosure.

[0034] It should be understood that when describing an element as "connected" or "linked" to another element, the element may be directly connected or linked to the other element, or it may be connected or linked to the other element via a third element. Conversely, it should be understood that when an element is described as "directly connected to" or "directly linked to" another element, no other element is placed between them. Other expressions describing relationships between components (i.e., "between" and "directly between" or "adjacent to" and "directly adjacent to") need to be interpreted in the same way.

[0035] The terminology used in this specification is for the purpose of describing specific examples of implementations only and is not intended to limit this disclosure. The singular form may include the plural form unless there is an explicit contrary meaning in the context. It should be understood in this specification that the terms "comprising" or "having" indicate the presence of the features, quantities, steps, operations, components, parts, or combinations thereof described in the specification, but do not preclude the possibility of the presence or addition of one or more other features, quantities, steps, operations, components, parts, or combinations thereof.

[0036] Unless otherwise defined, all terms used herein (including technical or scientific terms) shall have the same meaning as commonly understood by one of ordinary skill in the art. If a term is not clearly defined in a common dictionary in this specification, it shall be interpreted as having the same meaning as in the context of the relevant art, and not as an ideal or overly formal meaning.

[0037] Descriptions of known components and processing techniques may be omitted to avoid unnecessarily obscuring the embodiments of this disclosure.

[0038] Throughout this specification, the same reference numerals refer to the same elements. Therefore, even if a reference numeral is not mentioned or described with reference to one drawing, it may be mentioned or described with reference to another drawing. Furthermore, even if a reference numeral is not shown in one drawing, it may be mentioned or described with reference to another drawing.

[0039] Additionally, the logic level of a signal may be different from or opposite to the logic level described. For example, a signal described as having a logic "high" level may optionally have a logic "low" level, and a signal described as having a logic "low" level may optionally have a logic "high" level.

[0040] The embodiments of this disclosure will now be described in detail with reference to the accompanying drawings. However, those skilled in the art will understand that many technical details have been provided in the embodiments of this disclosure to facilitate a better understanding of the disclosure. However, the technical solutions claimed in this disclosure can be implemented even without these technical details and various variations and modifications based on the following embodiments.

[0041] Please see Figure 1 , Figure 2 , Figure 1 This is a flowchart illustrating a method for installing and debugging a frequency-modulated lidar scanning reflector according to an embodiment of the present invention. Figure 2 This is a schematic diagram illustrating the measurement principle of a frequency-modulated lidar scanner, illustrating an embodiment of the present invention's method for installing and debugging a frequency-modulated lidar scanning reflector. The method for installing and debugging a frequency-modulated lidar scanning reflector according to the present invention includes:

[0042] S1. The frequency-modulated lidar scanner to be debugged is installed and fixed on the workbench of the test equipment.

[0043] S2. Start the frequency-modulated lidar scanner, rotate the pitch axis to the 0° position, start the test equipment, measure the reflective surface of the reflector of the frequency-modulated lidar scanner, measure at least three non-collinear points, and fit the plane of the reflector by the three points.

[0044] S3. Rotate the pitch axis of the frequency-modulated laser radar scanner to a preset position, and measure the three non-collinear points on the reflective surface again using the test equipment, and then fit the scanning reflective mirror plane at this time.

[0045] S4. Analyze the two scanning mirror planes before and after to obtain their included angle θ, and at the same time measure the distance SS' between the two scanning mirror planes at the pitch axis position.

[0046] S5. Scan the angle between the plane of the reflector and the pitch axis to θ / 2 and the distance to SS' / 2. Modify the mounting plane of the reflector before and after scanning, and reinstall the reflector to eliminate the angle and distance.

[0047] S6. Repeat steps S1 to S5 to obtain the angle between the two front and rear scanning mirror planes and the distance between the two scanning mirror planes at the current pitch axis position until the measured angle is not greater than the preset angle and the distance is not greater than the preset distance, then the design requirements are met.

[0048] Specifically, the preset position is a 180° position.

[0049] Specifically, the preset angle is 0.001°.

[0050] Specifically, the preset distance is 0.01mm.

[0051] Specifically, step S4 involves analyzing the two scanning mirror planes, including using the test equipment control software to analyze the two scanning mirror planes.

[0052] Specifically, in step S5, scanning the angle between the reflector plane and the pitch axis is θ / 2 and the distance is SS' / 2, which includes scanning the angle between the reflector plane and the pitch axis as θ / 2 and the distance as SS' / 2 according to the spatial relationship.

[0053] The frequency-modulated lidar scanning mirror installation and debugging method of the present invention is based on the analysis of the above-mentioned scanning mirror installation and debugging method. By using the principle of rotational symmetry, the pitch axis is rotated 180°, and the reflective surface before and after rotation is measured by a coordinate measuring machine. The spatial distance between the centers of the reflective mirror and the included angle of the mirror surface before and after rotation are measured. Thus, the installation error of the scanning mirror is accurately measured. By adjusting the position of the reflector, high-precision and high-efficiency installation and debugging of the scanning mirror can be achieved.

[0054] In one embodiment of the present invention, the frequency-modulated lidar scanner is a non-contact, large-size, high-precision three-dimensional measuring instrument that obtains the three-dimensional coordinates of the measured point in a polar coordinate system through high-precision ranging and two-dimensional high-precision angle measurement. In actual engineering development, the scanning mirror of the frequency-modulated lidar scanner is an important optical component, thereby establishing a measurement coordinate system for three-dimensional scanning. The measurement laser of the frequency-modulated lidar is emitted upward by the laser emitting unit located on the underside of the device, and after passing through the scanning mirror, it performs a three-dimensional scan of the target. The reflection point is the origin of the measurement coordinate system, and the azimuth 0° and elevation 0° are the X-axis and Z-axis of the measurement coordinate system, respectively. The measurement coordinate system is thus established as follows: Figure 1 As shown. To ensure the stability of the coordinate system, the spatial position of the reflectors needs to be precisely adjusted. Specifically, the angle between the reflector surface and the pitch axis must not exceed 0.001°, and the distance between the reflector center and the pitch axis must not exceed 0.01mm. Ensuring these technical specifications is a key challenge for achieving high-precision three-dimensional scanning measurement with frequency-modulated lidar. Therefore, this invention proposes a method for installing and adjusting the scanning reflector of a frequency-modulated lidar, precisely measuring and adjusting the spatial position of the scanning reflector to achieve high-precision installation and adjustment.

[0055] In one embodiment of the present invention, based on the principle of rotational symmetry, the reflective surface is measured before and after rotation by rotating the pitch axis by 180° using a coordinate measuring machine. The spatial distance between the centers of the reflective surfaces before and after rotation is measured, and the included angle between the mirror surfaces before and after rotation is calculated. According to spatial relationships, the angle between the reflector and the pitch axis is half the included angle between the mirror surfaces before and after rotation, and the distance between the center of the reflector and the pitch axis is half the distance between the centers of the mirror surfaces before and after rotation. Based on the measurement results, the mechanical structure is adjusted, the mounting plane of the reflector before and after scanning is repaired, and then measurements are performed again until the measurement indicators meet the technical requirements, at which point the scanning reflector is fixed.

[0056] Figure 3 , Figure 4 middle, Figure 3 This is a schematic diagram of the installation position of a frequency-modulated lidar scanning reflector installation and debugging method according to an embodiment of the present invention. Figure 4 This is a schematic diagram of the mirror surface and elevation axis distance measurement model for a frequency-modulated lidar scanning mirror installation and debugging method according to an embodiment of the present invention. The O-XYZ coordinate system is the turntable coordinate system, where OY is the elevation rotation axis, OZ is the azimuth rotation axis, and OX is one axis of the turntable rectangular coordinate system defined according to the right-hand rule, which is the theoretical laser emission direction. FFGH is the reflecting mirror surface, and S is the intersection point of the reflecting mirror surface and OX.

[0057] Specifically, when adjusting the reflector surface, it is necessary to ensure that OS is within 0.05mm and the angle between OY and the reflector surface is less than 0.002°.

[0058] Specifically, the testing equipment is a coordinate measuring machine (CMM). The radar component under test is placed on the CMM's worktable and fixed stably to ensure that the CMM can easily test the reflector.

[0059] Please see Figure 5 , Figure 5 This is a schematic diagram of a measurement model for the angle between the mirror surface and the pitch axis in a frequency-modulated lidar scanning mirror installation and debugging method according to an embodiment of the present invention. The basic adjustment method involves a servo system controlling the azimuth axis for stability, and a pitch motor rotating to position the mirror at 0° and 180° respectively. Before rotation, the FFGH plane is measured and fitted using a coordinate measuring machine (CMM). Similarly, after rotation, the FFGH plane is fitted again using a CMM. A normal line passing through the mirror center point S of the fitted plane before rotation is used as the measurement axis (OX axis). The distance (SS') between this axis and the intersection point of the two fitted planes before and after rotation is measured. Half of this distance is OS. OS is measured on a CMM; a value less than 0.05 mm is considered satisfactory.

[0060] Specifically, the angle between the pitch axis OY and the reflecting mirror is defined as the angle between the projection of the reflecting surface onto the OXY plane and OY.

[0061] Specifically, the included angle θ can be easily measured using a coordinate measuring machine. θ / 2 is the angle between the mirror and the pitch axis, and a value less than 0.002° is sufficient to meet the requirements.

[0062] During the measurement process, it is necessary to test the fixture to fix the reflector. If the distance or angle does not meet the requirements, the reflector mount should be repaired according to the test direction until the test technical requirements are met. After fixing, the reflector can be fixed. After fixing, the distance and angle should be tested again after 12 hours, and they must still meet the technical requirements. If the indicators deviate, the problem should be found and the device reinstalled and tested until the technical requirements are met. At this point, the reflector testing and installation are complete.

[0063] In summary, the debugging of the frequency-modulated lidar scanning mirror is based on the rotational symmetry of the mirror surface. The mirror's pitch and tilt axes are measured and fitted before and after a 180° rotation using a coordinate measuring machine. This yields the distance and angular relationship between the pitch axis and the mirror surface. By adjusting the mirror surface, the mirror surface is aligned with the pitch axis. The entire debugging method does not require complicated procedures, and both accuracy and efficiency are greatly improved.

[0064] The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit the invention. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in the present invention should still be covered by the claims of the present invention.

Claims

1. A frequency-modulated ladar scanning mirror installation and commissioning method, characterized by, The application relates to a method for adjusting a frequency-modulated laser radar scanner, and belongs to the technical field of frequency-modulated laser radar scanner adjustment. S1, fixing a frequency-modulated laser radar scanner to be adjusted on a test equipment workbench; S2, starting the frequency-modulated laser radar scanner, rotating an elevation shaft to a 0-degree position, starting the test equipment, measuring a reflecting surface of a reflecting mirror of the frequency-modulated laser radar scanner, and measuring at least three non-collinear points to fit a scanning mirror plane through the three points; S3, rotating the elevation shaft of the frequency-modulated laser radar scanner to a preset position, measuring three non-collinear points of the reflecting surface through the test equipment again, and fitting a scanning mirror plane at the moment again; S4, analyzing the two scanning mirror planes before and after scanning, obtaining an included angle theta, and measuring the distance SS' of the two scanning mirror planes at the position of the elevation shaft; S5, scanning the included angle theta / 2 between the reflecting mirror plane and the elevation shaft and the distance SS' / 2, modifying the installation planes of the reflecting mirrors before and after scanning, and re-installing the reflecting mirrors to eliminate the included angle and the distance.

2. The method of mounting and commissioning a frequency-modulated ladar scanning mirror of claim 1, wherein, Further comprising: S6, executing the steps S1 to S5 again to obtain the included angle between the two scanning mirror planes before and after scanning and the distance of the two scanning mirror planes at the position of the elevation shaft until the measured included angle is not greater than a preset angle and the distance is not greater than a preset distance, and then the design requirement is met.

3. The method of mounting and commissioning a frequency-modulated ladar scanning mirror of claim 1, wherein: The preset position is a 180-degree position.

4. The method of mounting and commissioning a frequency-modulated ladar scanning mirror of claim 2, wherein: The preset angle is 0.001 degrees.

5. The method of mounting and commissioning a frequency-modulated ladar scanning mirror of claim 4, wherein: The preset distance is 0.01 mm.

6. The method of mounting and commissioning a frequency-modulated ladar scanning mirror of claim 1, wherein: The analysis of the two scanning mirror planes before and after scanning in the step S4 comprises analyzing the two scanning mirror planes before and after scanning through test equipment control software.

7. The method of mounting and commissioning a frequency-modulated ladar scanning mirror of claim 1, wherein: The scanning of the included angle theta / 2 between the reflecting mirror plane and the elevation shaft and the distance SS' / 2 in the step S5 comprises scanning the included angle theta / 2 between the reflecting mirror plane and the elevation shaft and the distance SS' / 2 according to the spatial relationship.

8. The frequency-modulated ladar scanning mirror installation and commissioning method of any of claims 1-7, wherein: The test equipment is a three-coordinate measuring machine.

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