Calibration control method and system for laser scanning equipment and electronic equipment

Abstract

The invention provides a calibration control method and system for laser scanning equipment and electronic equipment, and relates to the field of laser scanning equipment calibration, in the method, a special calibration block comprising a protruding part is used for calibrating the laser scanning equipment, calibration of external parameters can be completed only through one-time collection, and the operation process is simplified; according to the method, the calibration control process is achieved through the intersection points between the characteristic lines of the calibration block and the laser plane of the laser scanning equipment, the length of the direction of the characteristic lines is not required, only the laser stripes need to cover the multiple characteristic lines, and the calibration precision is improved.

Description

Technical Field

[0001] This invention relates to the field of laser scanning equipment calibration, and in particular to a calibration control method, system and electronic equipment for laser scanning equipment. Background Technology

[0002] Laser scanning equipment is commonly used in various industrial inspection scenarios such as contour scanning and surface defect detection. It projects a laser plane onto the surface of the object being measured, forming a laser stripe. The surface contour data of the object can then be obtained by extracting and calculating from this laser stripe. In some applications, it is necessary to accurately obtain the position and attitude parameters of the laser scanning equipment itself to precisely reconstruct the scan data output by the equipment.

[0003] Because laser scanning equipment requires high measurement accuracy, existing technologies require repeated calibration using specific calibration blocks, which is not only complex but also yields unsatisfactory calibration results. Summary of the Invention

[0004] In view of this, the purpose of the present invention is to provide a calibration control method, system and electronic device for laser scanning equipment. The method uses a special calibration block with protrusions to calibrate the laser scanning equipment, and the calibration of external parameters can be completed with only one acquisition, simplifying the operation process. The method uses the intersection point between the feature lines of the calibration block and the laser plane of the laser scanning equipment to realize the calibration control process. There are no requirements on the direction and length of the feature lines, as long as the laser stripes can cover several feature lines, which improves the calibration accuracy and solves the above-mentioned problems existing in the prior art.

[0005] In a first aspect, embodiments of the present invention provide a calibration control method for a laser scanning device, the method comprising: Acquire a calibration block associated with a laser scanning device; wherein the protruding surface of the calibration block is provided with multiple reflective units; The feature line corresponding to the calibration block is determined based on the intersection line between adjacent reflective units, and the position and orientation parameters corresponding to the feature line are determined using the first coordinate system corresponding to the calibration block. When the calibration block is detected to be placed at the corresponding calibration position of the laser scanning device, the laser scanning device is controlled to project a laser plane onto the reflective unit using preset scanning parameters, and the laser stripes formed on the surface of the reflective unit are acquired in real time. The intersection parameters of the feature line and the laser stripe are determined using the second coordinate system corresponding to the laser scanning device, and the position vector and attitude matrix corresponding to the first coordinate system and the second coordinate system are calculated using the position parameters, direction parameters and intersection parameters; The external parameter calibration results of the laser scanning equipment are determined by the position vector and attitude matrix.

[0006] Optionally, the step of determining the feature line corresponding to the calibration block based on the intersection line between adjacent reflective units, and determining the position and orientation parameters corresponding to the feature line using the first coordinate system corresponding to the calibration block, includes: Obtain the first coordinate system corresponding to the calibration block, and obtain the reflection plane corresponding to each reflection unit based on the first coordinate system; Determine the intersection line between adjacent reflection planes corresponding to adjacent reflection units, and determine the feature line corresponding to the calibration block based on the intersection line; Obtain the coordinate and direction values ​​of the target point in the feature line, and determine the position and direction parameters corresponding to the coordinate and direction values ​​based on the first coordinate system.

[0007] Optionally, when the calibration block is detected to be placed at the corresponding calibration position on the laser scanning device, the step of controlling the laser scanning device to project a laser plane onto the reflecting unit using preset scanning parameters and acquiring the laser stripes formed on the surface of the reflecting unit in real time includes: Determine the preset calibration position in the laser scanning equipment and acquire the position sensor and image sensor corresponding to the calibration position; wherein, the calibration position is located in the laser irradiation area of ​​the laser scanning equipment; When the position sensor detects that the calibration block is placed at the calibration position, the preset scanning parameters are used to determine the corresponding line scan laser trigger command and its corresponding laser plane of the laser scanning device. According to the laser trigger command of the line scan, the laser scanning equipment is controlled to project the laser plane onto the reflection unit corresponding to the calibration block; The laser stripes formed on the surface of the reflective unit in the protrusion are detected and acquired in real time using an image sensor.

[0008] Optionally, the intersection parameters of the feature line and the laser stripe are determined using the second coordinate system corresponding to the laser scanning device, including: Obtain the second coordinate system corresponding to the laser scanning device; Determine the first and second planes corresponding to the adjacent reflective units of the feature line, and obtain the first laser stripe in the first plane and the second laser stripe in the second plane. Based on the second coordinate system, obtain the first straight line expression corresponding to the first laser stripe and the second straight line expression corresponding to the second laser stripe respectively; The first intersection point between the feature line and the laser stripe is calculated and obtained using the first and second line expressions. The intersection parameters of the feature line and the laser stripe are determined based on the coordinate parameters corresponding to the first intersection point in the second coordinate system.

[0009] Optionally, the position vector and attitude matrix corresponding to the first coordinate system and the second coordinate system are calculated using position parameters, orientation parameters, and intersection parameters, including: The first linear feature corresponding to the feature line is determined based on the planar feature data corresponding to the first plane and the second plane. After transforming the first linear feature from the first coordinate system to the second coordinate system based on the position and direction parameters, the second linear feature corresponding to the feature line is obtained, and the second intersection point is determined by the intersection point parameters of the second linear feature and the laser plane. The first intersection point is used as the observed data, and the second intersection point is used as the predicted data to obtain the deviation data between the observed data and the predicted data. The position vector and attitude matrix between the first coordinate system and the second coordinate system are determined using the deviation data.

[0010] Optionally, the position vector and attitude matrix satisfy the following relationship: ; ; in, The initial value corresponding to the feature line; This represents the current coordinate value corresponding to the feature line; For the first The second linear feature corresponding to each feature line; For the first The first linear feature corresponding to each feature line; For the first The position parameters of each feature line in the second coordinate system; For the first The position parameters of each feature line in the first coordinate system; For the first The direction parameters of each feature line in the second coordinate system; For the first The direction parameters of each feature line in the first coordinate system; This is the attitude matrix; It is a position vector; The second intersection point; The first intersection point; For laser plane; For the first The characteristic lines correspond to the following in the second coordinate system. Axis coordinate values; For the first The characteristic lines correspond to the following in the second coordinate system. Axis coordinate values; for The corresponding first vector component; for The corresponding second vector component; for The corresponding third vector component; for The corresponding first vector component; for The corresponding second vector component; for The corresponding third vector component.

[0011] Optionally, the step of determining the extrinsic parameter calibration results of the laser scanning device through the position vector and attitude matrix includes: Obtain the rotation vector corresponding to the attitude matrix; The initial values ​​of the external parameters corresponding to the laser scanning equipment are determined by the rotation vector and the position vector. Based on the initial values ​​of external parameters, position parameters, direction parameters, and intersection parameters, construct the fitness function and residual function corresponding to the laser scanning device respectively; The particle swarm optimization algorithm is used to obtain the first extrinsic parameter solution corresponding to the initial values ​​of the extrinsic parameters under the fitness function. One or more of the above nonlinear optimization algorithms, such as gradient descent, Newton's method, quasi-Newton's method, conjugate gradient method, and interior point method, are used to obtain the second extrinsic solution corresponding to the first extrinsic solution of the residual function; The calibration results of the external parameters corresponding to the laser scanning equipment are determined based on the second external parameter solution.

[0012] Optionally, the fitness function is: ; The residual function is: ; in, The fitness function; It is the residual function; The initial value corresponding to the feature line; This represents the current coordinate value corresponding to the feature line; The number of characteristic lines; This is the attitude matrix; It is a position vector; For the first The position parameters of each feature line in the first coordinate system; The first intersection point; For the first The direction parameters of each feature line in the first coordinate system; The vector to be determined is the vector corresponding to the position vector; Let be the vector to be determined corresponding to the rotation vector; This is the first external parameter solution.

[0013] In a second aspect, the present invention provides a calibration control system for a laser scanning device, the system comprising: An initialization module is used to acquire a calibration block associated with the laser scanning device; wherein, the protruding surface of the calibration block is provided with multiple reflective units; The feature line processing module is used to determine the feature line corresponding to the calibration block based on the intersection line between adjacent reflection units, and to determine the position parameters and direction parameters corresponding to the feature line using the first coordinate system corresponding to the calibration block. The laser irradiation control module is used to control the laser scanning device to project a laser plane onto the reflective unit using preset scanning parameters when the calibration block is detected to be placed at the corresponding calibration position of the laser scanning device, and to acquire the laser stripes formed on the surface of the reflective unit in real time. The calibration parameter determination module is used to determine the intersection parameters of the feature line and the laser stripe using the second coordinate system corresponding to the laser scanning device, and to calculate the position vector and attitude matrix corresponding to the first coordinate system and the second coordinate system using the position parameters, direction parameters and intersection parameters; The calibration execution control module is used to determine the external parameter calibration results of the laser scanning equipment through position vectors and attitude matrices.

[0014] Thirdly, embodiments of the present invention also provide an electronic device, which includes a processor and a memory, the memory storing computer-executable instructions that can be executed by the processor, the processor executing the computer-executable instructions to implement the steps of the calibration control method for a laser scanning device provided in the first aspect.

[0015] Fourthly, embodiments of the present invention also provide a storage medium storing computer-executable instructions, which, when invoked and executed by a processor, cause the processor to implement the steps of the calibration control method for a laser scanning device provided in the first aspect.

[0016] This invention provides a calibration control method, system, and electronic device for a laser scanning device. During the calibration process, the method first acquires a calibration block associated with the laser scanning device. The protruding surface of the calibration block is provided with multiple reflective units. Then, based on the intersection lines between adjacent reflective units, a feature line corresponding to the calibration block is determined, and the position and direction parameters corresponding to the feature line are determined using a first coordinate system corresponding to the calibration block. When the calibration block is detected to be placed at the calibration position corresponding to the laser scanning device, preset scanning parameters are used to control the laser scanning device to project a laser plane onto the reflective units, and laser stripes formed on the surface of the reflective units are acquired in real time. Subsequently, the intersection parameters of the feature line and the laser stripes are determined using a second coordinate system corresponding to the laser scanning device, and the position vector and attitude matrix corresponding to the first and second coordinate systems are calculated using the position, direction, and intersection parameters. Finally, the extrinsic parameter calibration result corresponding to the laser scanning device is determined using the position vector and attitude matrix. This method uses a special calibration block with protrusions to calibrate the laser scanning equipment, which can complete the calibration of external parameters with only one acquisition, simplifying the operation process. This method uses the intersection of the feature lines of the calibration block and the laser plane of the laser scanning equipment to realize the calibration control process. There are no requirements on the direction and length of the feature lines. It is only necessary for the laser stripes to cover a number of feature lines, which improves the calibration accuracy.

[0017] Other features and advantages of the invention will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing the invention. The objects and other advantages of the invention are realized and obtained in accordance with the structures particularly pointed out in the description, claims and drawings.

[0018] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, preferred embodiments are described below in detail with reference to the accompanying drawings. Attached Figure Description

[0019] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0020] Figure 1 A flowchart of a calibration control method for a laser scanning device provided in an embodiment of the present invention; Figure 2 This is a schematic diagram illustrating the correspondence between a calibration block and a laser scanning device in a calibration control method for a laser scanning device provided in an embodiment of the present invention. Figure 3 This is a flowchart of step S102 in a calibration control method for a laser scanning device provided in an embodiment of the present invention; Figure 4 This is a flowchart of step S103 in a calibration control method for a laser scanning device provided in an embodiment of the present invention; Figure 5 In step S104 of a calibration control method for a laser scanning device provided in an embodiment of the present invention, a flowchart is provided showing how to determine the intersection parameters of the feature line and the laser stripe using the second coordinate system corresponding to the laser scanning device. Figure 6 In step S104 of a calibration control method for a laser scanning device provided in an embodiment of the present invention, a flowchart is shown for calculating the position vector and attitude matrix corresponding to the first coordinate system and the second coordinate system using position parameters, direction parameters and intersection parameters; Figure 7 A flowchart of step S105 in a calibration control method for a laser scanning device provided in an embodiment of the present invention; Figure 8 In a calibration control method for a laser scanning device provided in an embodiment of the present invention, a diagram showing the correspondence between feature lines and laser stripes in a first coordinate system and a second coordinate system is provided. Figure 9 This is a schematic diagram of a calibration control system for a laser scanning device provided in an embodiment of the present invention; Figure 10 This is a schematic diagram of the structure of an electronic device provided in an embodiment of the present invention.

[0021] icon: 910 - Initialization module; 920 - Feature line processing module; 930 - Laser irradiation control module; 940 - Calibration parameter determination module; 950 - Calibration execution control module; 101 - Processor; 102 - Memory; 103 - Bus; 104 - Communication interface. Detailed Implementation

[0022] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0023] To facilitate understanding of this embodiment, a calibration control method for a laser scanning device disclosed in this embodiment of the invention will first be described, such as... Figure 1As shown, the method includes: Step S101: Obtain a calibration block associated with the laser scanning device; wherein, the protruding surface of the calibration block is provided with multiple reflective units.

[0024] First, a dedicated calibration block matching the laser scanning equipment to be calibrated is obtained. This calibration block must have a pre-defined protrusion structure (such as raised truncated pyramids, columnar protrusions, etc., to form clear geometric features), and multiple reflective units (such as high-reflectivity metal sheets, coated glass blocks, etc.) must be pre-fixed on the surface of the protrusion. The arrangement of the reflective units must ensure that the laser can be effectively reflected and form clearly identifiable laser stripes, providing a reliable reflective carrier for subsequent stripe acquisition and feature matching, and avoiding stripe blurring due to insufficient reflection, which would affect the subsequent calibration accuracy. This aligns with the core requirement of data acquisition source reliability in industrial testing.

[0025] Step S102: Determine the feature line corresponding to the calibration block based on the intersection line between adjacent reflective units, and determine the position and direction parameters corresponding to the feature line using the first coordinate system corresponding to the calibration block.

[0026] This step first identifies the physical intersection lines between adjacent reflective units on the surface of the calibration block protrusion (such as the intersection line of the edges of two perpendicular reflective units, the connecting edge line of adjacent reflective surfaces, etc.), and defines these intersection lines as the feature lines of the calibration block. Then, a first coordinate system dedicated to the calibration block (i.e., the coordinate system of the calibration block) is established. This can be achieved by using the geometric reference point of the calibration block (such as the center of symmetry of the protrusion, the vertex of a fixed reflective unit) as the origin, and a fixed edge of the calibration block as the coordinate axis (such as the X-axis along the length of the protrusion, and the Z-axis along the height of the protrusion), ensuring that the reference of the coordinate system is fixed. Subsequently, based on this first coordinate system, the position parameters (such as the three-dimensional coordinate values ​​of the two endpoints of the feature line in the first coordinate system) and direction parameters (such as the unit direction vector of the feature line, describing its direction in three-dimensional space) of each feature line are calculated through geometric measurement or preset design parameters, forming a complete parameter set of the feature lines, providing a reference for subsequent coordinate system transformation.

[0027] Step S103: When the calibration block is detected to be placed at the corresponding calibration position of the laser scanning device, the laser scanning device is controlled to project a laser plane onto the reflective unit using preset scanning parameters, and the laser stripes formed on the surface of the reflective unit are acquired in real time.

[0028] First, a mechanical limiting device or visual positioning system is used to check whether the calibration block is accurately placed in the preset calibration position of the laser scanning equipment (this position needs to be pre-calibrated to ensure the repeatability of each calibration block placement and reduce the impact of position deviation on calibration). If the position is confirmed to be accurate, preset scanning parameters (including laser power, laser plane projection angle, camera exposure time, scanning frame rate, etc., which need to be pre-optimized according to the reflectivity of the reflective unit and the ambient light intensity) are called to control the laser scanning equipment to project the laser plane onto the reflective unit of the protrusion of the calibration block. After the laser plane intersects with the surface of the reflective unit, a continuous laser stripe is formed. The image data of the laser stripe can be captured in real time by a relevant image acquisition module (such as an industrial camera) and transmitted to a relevant data processing unit for preliminary preprocessing (such as noise reduction and grayscale enhancement) to ensure that the stripe outline is clear and extractable.

[0029] Step S104: Determine the intersection parameters of the feature line and the laser stripe using the second coordinate system corresponding to the laser scanning device, and calculate the position vector and attitude matrix corresponding to the first coordinate system and the second coordinate system using the position parameters, direction parameters and intersection parameters.

[0030] First, a dedicated second coordinate system (i.e., the device coordinate system) is established for the laser scanning equipment. This is typically based on the origin of the laser emission point of the laser scanning equipment or the center of the lens of the image acquisition module, with the scanning direction of the equipment as the coordinate axis (e.g., the X-axis along the horizontal scanning direction and the Y-axis along the vertical direction), serving as the equipment's own measurement reference. Then, the contour of the pre-processed laser stripe image is extracted. Combined with the feature line parameters obtained in S102, relevant image matching algorithms (such as edge detection and line fitting) are used to determine the intersection parameters of each feature line with the laser stripe (i.e., the three-dimensional coordinate values ​​of the intersection points in the second coordinate system). Subsequently, based on spatial geometric principles (such as the formula for the intersection of a line and a plane, and the least squares method), the position parameters, direction parameters (from the first coordinate system), and intersection parameters (from the second coordinate system) of the feature lines are substituted into the coordinate transformation model to solve for the position vector (describing the three-dimensional offset of the origin of the calibration block coordinate system relative to the origin of the device coordinate system) and the attitude matrix (describing the rotational relationship between the coordinate axes of the two coordinate systems, which can be further converted into intuitive attitude parameters such as Euler angles) between the first coordinate system (calibration block) and the second coordinate system (equipment).

[0031] Step S105: Determine the external parameter calibration results of the laser scanning device through the position vector and attitude matrix.

[0032] The position vector and attitude matrix obtained from S104 are converted and verified (e.g., by reverse calculation to verify whether the error of the two coordinate system transformation is within the allowable range; if the error exceeds the tolerance, return to S103 to re-acquire stripes). After successful verification, the position offset of the device and calibration block corresponding to the position vector and the attitude rotation angle of the device and calibration block corresponding to the attitude matrix are integrated into the extrinsic parameter calibration results of the laser scanning device. These extrinsic parameters will be directly used for the accurate reconstruction of subsequent laser scanning data. In actual inspection, the device will convert the laser stripe data obtained from scanning (based on the device coordinate system) into actual three-dimensional spatial coordinates (based on the world coordinate system) according to the extrinsic parameters, ensuring that the contour data, defect location, and other information of the measured object are accurately matched with the actual physical space, ultimately solving the problems of repeated calibration and insufficient accuracy in the existing technology, and achieving the goal of completing accurate calibration in one acquisition.

[0033] The correspondence between calibration blocks and laser scanning equipment is as follows: Figure 2 As shown, multiple alumina ceramic plates are continuously placed on the calibration block plane. These alumina ceramic plates are custom-machined with a surface roughness of 0.001 mm, exhibiting excellent optical diffuse reflection properties. Alumina ceramics possess the physical characteristics of low absorption and high diffuse reflectance for line lasers. When laser light irradiates its surface, most of the laser energy is effectively reflected to the photosensitive unit of the profile measuring instrument, significantly improving the signal-to-noise ratio and measurement accuracy of data acquisition. The spatial pose relationship between the planes on the calibration block can be precisely measured to micrometers, and the intersection lines of the planes are not parallel in space. The line scanning laser plane of the laser scanning device irradiates the planes of the calibration block, forming multiple non-parallel coplanar laser intersection lines.

[0034] Optionally, step S102, which involves determining the feature line corresponding to the calibration block based on the intersection line between adjacent reflective units and determining the position and orientation parameters of the feature line using the first coordinate system corresponding to the calibration block, is as follows: Figure 3 As shown, it includes: Step S301: Obtain the first coordinate system corresponding to the calibration block, and obtain the reflection plane corresponding to each reflection unit based on the first coordinate system.

[0035] First, a unique first coordinate system (i.e., the calibration block coordinate system) is established for the calibration block. This coordinate system must be based on the physical geometric reference of the calibration block. Usually, a fixed reference point on the calibration block (such as the center of symmetry of the protrusion or the vertex of a corner of a certain reflective unit) is selected as the origin, and the rigid edges of the calibration block (such as the length edge of the protrusion or the edge perpendicular to the surface of the reflective unit) are used as the coordinate axes (for example, the X-axis extends horizontally along the protrusion, the Y-axis extends horizontally along the surface of the reflective unit, and the Z-axis is perpendicular to the surface of the reflective unit). This ensures the uniqueness and stability of the coordinate system and avoids reference deviations in subsequent parameter calculations.

[0036] Then, based on the first coordinate system, the parameters of the reflection plane corresponding to each reflection unit are obtained. Since the reflection unit (such as a metal reflector or coated glass) is fixedly installed on the surface of the protrusion of the calibration block, the spatial orientation of its reflection surface has been predetermined. The reflection plane can be obtained in two ways: First, by using the design drawings of the calibration block, the installation position and angle of the reflection unit in the first coordinate system are extracted, and the equation of the reflection plane (such as Ax+By+Cz+D=0) is directly calculated. Second, the surface of the reflection unit is sampled by a precision measuring tool (such as a coordinate measuring machine), and the parameters of the reflection plane are fitted to ensure that the reflection plane is completely matched with the actual physical surface, providing an accurate plane reference for subsequent intersection calculation.

[0037] Step S302: Determine the intersection line between adjacent reflection planes corresponding to adjacent reflection units, and determine the feature line corresponding to the calibration block based on the intersection line.

[0038] First, the adjacency relationship of all reflective units on the protruding surface of the calibration block is identified. Based on the spatial arrangement (such as matrix arrangement or ring arrangement) or physical connection relationship (such as sharing the same mounting base or closely adjacent edges) of the reflective units, it is determined which reflective units belong to adjacent reflective units (it is necessary to avoid misjudging non-physically adjacent reflective units, which would result in invalid intersection lines).

[0039] Then, the spatial intersection line of the adjacent reflecting planes corresponding to the adjacent reflecting units is solved. Specifically, based on the equations of the two adjacent reflecting planes obtained in S301, the intersection line of the two planes is calculated through spatial geometric operations (such as solving the equations of the two planes simultaneously, solving for the line parameters that satisfy the two equations, and obtaining the direction vector of the intersection line and the coordinates of a certain reference point).

[0040] Finally, the intersection line is defined as the feature line of the calibration block, and the validity of the intersection line needs to be verified. If the two reflection planes are parallel or nearly parallel (the intersection line does not exist or the direction is ambiguous), the adjacent reflection unit needs to be reselected. Only the intersection line with clear lines and spatial uniqueness can be used as the feature line to ensure that the subsequent intersection point with the laser stripe can be accurately matched, and to avoid the decrease in calibration accuracy due to the invalid feature line.

[0041] Step S303: Obtain the coordinate and direction values ​​corresponding to the target point in the feature line, and determine the position and direction parameters corresponding to the coordinate and direction values ​​based on the first coordinate system.

[0042] First, select target points on the determined feature lines. The target points should be easy to identify and measure. Prioritize the endpoints of the feature lines (such as the intersection of the edges of the reflective units, the intersection of the reflective plane and the outer shell of the calibration block), the midpoint (the geometric center of the feature line), or the intersection of the feature line with other reference structures of the calibration block (such as the intersection of the vertex of the protrusion and the feature line). Select at least two target points for each feature line (to determine the direction), and the target points should be evenly distributed on the feature line to avoid parameter calculation deviations due to excessive concentration of points.

[0043] Then, obtain the coordinates of the target point and the direction of the feature line; based on the first coordinate system established by S301, directly read the three-dimensional coordinates of the target point through relevant measurement tools, or derive the coordinates of the target point according to the preset installation parameters of the reflection unit; then, calculate the direction vector (i.e., direction value) of the feature line through the coordinate difference between the two target points, and normalize it to a unit direction vector (to facilitate subsequent coordinate system transformation calculations).

[0044] Finally, the coordinate and direction values ​​are converted into position and direction parameters of the feature line. The position parameters are presented as the coordinate range of the target points at both ends of the feature line in the first coordinate system or the coordinates of the midpoint of the feature line plus the length, which clearly describes the spatial position of the feature line in the first coordinate system. The direction parameters are presented as normalized unit direction vectors (such as (X,Y,Z)) which accurately describe the direction of the feature line in three-dimensional space, thus forming a complete parameter set of the feature line, providing reference data for coordinate system transformation in S104.

[0045] Optionally, when the calibration block is detected to be placed at the corresponding calibration position of the laser scanning device, the laser scanning device is controlled to project a laser plane onto the reflecting unit using preset scanning parameters, and the laser stripes formed on the surface of the reflecting unit are acquired in real time, as in step S103. Figure 4 As shown, it includes: Step S401: Determine the preset calibration position in the laser scanning device, and acquire the position sensor and image sensor corresponding to the calibration position; wherein, the calibration position is located in the laser irradiation area of ​​the laser scanning device.

[0046] First, the pre-set calibration position of the laser scanning equipment must be clearly defined. This position must be strictly within the laser irradiation coverage area of ​​the equipment (to ensure that the subsequent laser plane can be completely projected onto the reflective unit of the calibration block, avoiding the loss of stripes due to the laser not covering the area). It is usually calibrated by the mechanical reference of the equipment (such as positioning pins or limit baffles) to ensure the consistency of the placement of the calibration block each time.

[0047] Then, the two types of core sensors corresponding to the calibration position are matched: one is a position sensor (such as a photoelectric proximity switch, laser displacement sensor or mechanical limit sensor, used to detect whether the calibration block is physically in place), and the other is an image sensor (such as an industrial CCD / CMOS camera, which needs to be pre-calibrated with the laser projection direction and the position of the calibration block to ensure that the laser stripes formed on the surface of the reflective unit can be completely captured). Both types of sensors need to complete parameter calibration in advance (such as the trigger threshold of the position sensor, the focal length and exposure parameters of the image sensor) to provide reliable hardware support for subsequent detection and acquisition.

[0048] Step S402: When the position sensor detects that the calibration block is placed at the calibration position, the laser scanning device is used to determine the corresponding line scan laser trigger command and its corresponding laser plane using preset scanning parameters.

[0049] First, the real-time detection function of the position sensor is activated. When the position sensor detects that the physical contour of the calibration block (such as the edge of the protrusion or the mounting base of the reflective unit) reaches the preset trigger condition (such as the distance between the sensor and the calibration block being less than 0.5mm or mechanical limit trigger), it is determined that the calibration block has been accurately placed in the calibration position.

[0050] Then, the preset scanning parameters in the device are called (including laser power, laser plane projection angle, laser line width, scanning trigger frequency, etc. These parameters need to be optimized according to the reflectivity of the reflective unit. For example, the laser power can be reduced for high reflectivity reflective units to avoid stripe overexposure). Based on these parameters, the line scan laser trigger command of the laser scanning device (including laser emission timing and power adjustment signal) is generated. At the same time, the spatial parameters of the laser plane are determined (such as the normal vector of the plane and the expected intersection area between the plane and the calibration block reflective unit) to ensure that the laser plane can accurately cover the surface of the reflective unit corresponding to at least two feature lines.

[0051] Step S403: Control the laser scanning device to project the laser plane onto the reflection unit corresponding to the calibration block according to the line scan laser trigger command.

[0052] After receiving the line scan laser trigger command generated by S402, the control unit of the laser scanning equipment drives the laser emission module (such as a semiconductor laser or galvanometer scanning system) to work according to the command parameters. By adjusting the laser emission angle to a preset value, a laser beam of corresponding power is output, and the laser beam is expanded into a laser plane of preset thickness by optical elements (such as cylindrical mirrors).

[0053] When the laser plane is projected onto the surface of the reflective unit of the protruding part of the calibration block, it must be ensured that the intersection area of ​​the plane and the reflective unit is unobstructed (such as avoiding the equipment casing or cables blocking the laser), and that the laser stripe formed by the intersection is continuous and unbroken; if obstruction or breakage occurs, the equipment can trigger an alarm signal to prompt the adjustment of the calibration block position or the removal of obstructions to ensure the effectiveness of stripe acquisition.

[0054] Step S404: Use an image sensor to detect and acquire the laser stripes formed on the surface of the reflective unit in the protrusion in real time.

[0055] Synchronized with laser projection, the device's image sensor initiates real-time shooting at a preset frame rate (e.g., 30fps-60fps, to ensure the complete outline of the dynamic laser stripes is captured): the image sensor focuses the laser stripes on the surface of the reflective unit through the lens, converts the light signal into an electrical signal, and generates a grayscale image of the stripes.

[0056] During the acquisition process, the image sensor performs preliminary preprocessing on the original image (such as automatic noise reduction, grayscale enhancement, and contrast adjustment) to reduce the impact of ambient stray light on the clarity of the stripes. The preprocessed laser stripe image is transmitted to the device's data buffer unit in real time, providing a high-quality image data foundation for the subsequent extraction of feature lines and stripe intersections in S104.

[0057] Optionally, the intersection parameters of the feature line and the laser stripe can be determined using the second coordinate system corresponding to the laser scanning device, such as... Figure 5 As shown, it includes: Step S501: Obtain the second coordinate system corresponding to the laser scanning device.

[0058] First, define the dedicated second coordinate system (i.e., the "device coordinate system") for the laser scanning equipment. This coordinate system is the core reference for the equipment's measurement and data calculation. It is typically established with the equipment's key physical center as the origin; such as the laser emission point of the laser emitting module, the lens optical center of the image acquisition module (industrial camera), or the equipment's mechanical positioning reference point. The coordinate axis directions must be related to the actual working state of the equipment. For example, the X-axis is along the horizontal scanning direction of the equipment, the Y-axis is along the vertical direction, and the Z-axis is perpendicular to the scanning plane. This ensures that the coordinate system accurately maps the equipment's three-dimensional measurement space, providing a unified equipment-side reference framework for subsequent fringe expression derivation and intersection point calculation.

[0059] Step S502: Determine the first plane and the second plane corresponding to the adjacent reflective units of the feature line, and obtain the first laser stripe in the first plane and the second laser stripe in the second plane.

[0060] In this step, the physical carrier corresponding to the feature line is first identified. Since the feature line is determined by the intersection line of adjacent reflective units, the first and second planes corresponding to these two adjacent reflective units are first located (i.e., the reflective working surfaces of the reflective units, whose plane parameters can be pre-obtained based on the installation position and orientation of the reflective units in S102). Then, the laser plane projected by the laser scanning device intersects with the first and second planes respectively. Due to the different spatial orientations of the two planes (the angular differences between adjacent reflective units), two independent laser stripes will be formed on their respective surfaces: defined as the first laser stripe (on the first plane) and the second laser stripe (on the second plane). Subsequently, the image acquisition module of the device captures the image data of these two laser stripes and performs preliminary preprocessing (such as noise reduction and edge enhancement) to ensure that the stripe outline is clear and to avoid deviations in subsequent straight line fitting due to stripe blurring.

[0061] Step S503: Based on the second coordinate system, obtain the first line expression corresponding to the first laser stripe and the second line expression corresponding to the second laser stripe.

[0062] Based on the second coordinate system established by S501, geometric models are performed on the two laser stripes to obtain their corresponding linear expressions. Specifically, for the preprocessed image of the first laser stripe, an edge detection algorithm (such as the Canny operator) can be used to extract the pixel-level edges of the stripe, and then a linear fitting algorithm (such as the least squares method) can be used to obtain the linear equation of the stripe in the image pixel coordinate system. Using the "camera calibration parameters" pre-completed by the device (establishing a mapping relationship between pixel coordinates and the three-dimensional spatial coordinates of the second coordinate system), the linear equation in the pixel coordinate system is converted into the first linear expression in the second coordinate system. Then, the same process is followed for the second laser stripe to perform edge extraction, fitting, and coordinate transformation to obtain the second linear expression in the second coordinate system, ensuring that the mathematical forms of the two expressions are consistent, laying the foundation for subsequent simultaneous solution.

[0063] Step S504: Calculate and obtain the first intersection point between the feature line and the laser stripe using the first and second line expressions.

[0064] First, clarify the physical meaning of the intersection point: the feature line is the intersection line between the first plane and the second plane, while the first laser stripe and the second laser stripe are the intersection lines between the laser plane and the two planes, respectively. Therefore, the common intersection point of the three lines (the intersection line between the first plane and the intersection line between the laser plane and the two planes) is the actual intersection point (the first intersection point) between the feature line and the laser stripe.

[0065] Then, by combining the first and second line expressions obtained from S503, the system of equations is solved through algebraic operations (such as substitution elimination and matrix solving) to obtain a unique three-dimensional spatial coordinate point, which is then determined as the first intersection point.

[0066] Step S505: Determine the intersection parameters of the feature line and the laser stripe based on the coordinate parameters corresponding to the first intersection point in the second coordinate system.

[0067] First, the three-dimensional coordinate parameters of the first intersection point in the second coordinate system are extracted. The coordinate accuracy must match the measurement level of the laser scanning equipment, as it directly reflects the specific position of the intersection point in the equipment's measurement space. Then, by combining the error data of the fringe fitting (such as the root mean square error of the straight line fitting) and the deviation value of the coordinate transformation, an accuracy evaluation index is added to the intersection point coordinates to quantify the reliability of the intersection point parameters. Finally, the three-dimensional coordinate parameters and the accuracy evaluation index are integrated into the intersection parameters of the feature line and the laser fringe. This parameter will serve as the core input data for subsequent calculations of the position vector and attitude matrix of the first and second coordinate systems, ensuring the accuracy of the coordinate system transformation.

[0068] Optionally, the position vector and attitude matrix corresponding to the first coordinate system and the second coordinate system can be calculated using position parameters, orientation parameters, and intersection parameters, such as... Figure 6 As shown, it includes: Step S601: Determine the first linear feature corresponding to the feature line based on the planar feature data corresponding to the first plane and the second plane.

[0069] First, retrieve the planar feature data corresponding to the first plane (the reflecting surface of one of the adjacent reflecting units) and the second plane (the reflecting surface of another adjacent reflecting unit) locked in step S502. This data includes the plane equations, normal vector parameters, and plane boundary coordinates of the two planes in the first coordinate system (calibration block coordinate system). These data need to be pre-calibrated based on the installation parameters of the reflecting units in S102 and the reference of the first coordinate system to ensure the accuracy of the planar features.

[0070] Next, based on the principles of spatial geometry, the equations of the first and second planes are solved simultaneously to find the line of intersection; this line of intersection is the feature line of the calibration block. This line of intersection is defined as the first linear feature in the form of a parametric geometric description, usually presented using a point-to-point equation. The first linear feature is essentially a complete mathematical model of the feature line in the first coordinate system, providing the original geometric reference for subsequent cross-coordinate system transformations.

[0071] Step S602: Based on the position parameters and direction parameters, the first linear feature is transformed from the first coordinate system to the second coordinate system to obtain the second linear feature corresponding to the feature line, and the second intersection point is determined by the intersection point parameters of the second linear feature and the laser plane.

[0072] This step first transforms the coordinate system of the first linear feature: based on the feature line position parameters (such as the coordinates of the reference point in the first coordinate system) and direction parameters (such as the direction vector) obtained in step S102, the first linear feature is transformed from the first coordinate system (calibration block) to the second coordinate system (laser scanning device) through a coordinate system transformation model (preliminarily associating the mapping relationship between the first coordinate system and the second coordinate system, such as temporary translation and coarse rotation angle), to obtain the second linear feature; its mathematical form is consistent with that of the first linear feature (such as maintaining the point-direction equation), only the coordinate reference is updated to the device coordinate system to ensure the compatibility of subsequent calculations.

[0073] Then, determine the mathematical expression of the laser plane: retrieve the preset laser scanning parameters (such as laser projection angle and the coordinates of the second coordinate system of the emission center) in step S103, and combine them with the intersection logic of the laser plane and the reflection unit to derive the plane equation of the laser plane in the second coordinate system. This equation needs to accurately reflect the spatial attitude of the laser plane. If there is a deviation in equipment installation (such as slight tilt of laser projection), it needs to be corrected by the previous calibration parameters to avoid distortion of the plane equation.

[0074] Finally, the second intersection point is calculated: the equations of the second linear feature line and the laser plane are combined, and algebraic operations (such as substitution elimination or matrix solving) are used to obtain a unique three-dimensional spatial coordinate point. This point is the second intersection point, representing the theoretical intersection position of the transformed feature line and the laser plane in the device coordinate system.

[0075] Step S603: Use the first intersection point as the observed data and the second intersection point as the predicted data to obtain the deviation data between the observed data and the predicted data.

[0076] The observation data is the first intersection point obtained in step S504. This intersection point is the actual measured coordinate of the feature line (physical entity) and the laser stripe (the intersection line of the actual acquired laser plane) in the second coordinate system, which directly reflects the real physical position. The accuracy of the data depends on the quality of laser stripe extraction and fitting.

[0077] The predicted data is the second intersection point obtained in step S602. This intersection point is the calculated coordinate of the feature line (the theoretical model after coordinate system transformation) and the laser plane (theoretical equation) in the second coordinate system, representing the intersection position under the ideal state.

[0078] When calculating the deviation data between these two types of data, the core focus is on the three-dimensional coordinate difference, quantifying the difference between them. Commonly used forms include: coordinate component deviation, Euclidean distance deviation, and sum of squared deviations. The deviation data intuitively reflects the degree of fit between the theoretical model and the actual measurement, and is the core basis for subsequent solutions to the position vector and attitude matrix.

[0079] Step S604: Use the deviation data to determine the corresponding position vector and attitude matrix between the first coordinate system and the second coordinate system.

[0080] Deviation data characterizes the position transformation relationship between the first and second intersection points. A corresponding position transformation model can be constructed using deviation data. The second coordinate system coordinates of the first and second intersection points are taken as a pair of corresponding points. Finally, the position vector and attitude matrix are solved. The least squares method is used to fit multiple pairs of points to minimize the error between the theoretical transformation coordinates and the actual intersection coordinates. Thus, a unique attitude matrix (describing the rotation relationship of the first coordinate system relative to the second coordinate system, such as the rotation angle around the X, Y, and Z axes) and position vector (describing the three-dimensional offset of the origin of the first coordinate system relative to the origin of the second coordinate system) are calculated.

[0081] Optionally, the position vector and attitude matrix satisfy the following relationship: ; ; in, The initial value corresponding to the feature line; This represents the current coordinate value corresponding to the feature line; For the first The second linear feature corresponding to each feature line; For the first The first linear feature corresponding to each feature line; For the first The position parameters of each feature line in the second coordinate system; For the first The position parameters of each feature line in the first coordinate system; For the first The direction parameters of each feature line in the second coordinate system; For the first The direction parameters of each feature line in the first coordinate system; This is the attitude matrix; It is a position vector; The second intersection point; The first intersection point; For laser plane; For the first The characteristic lines correspond to the following in the second coordinate system. Axis coordinate values; For the first The characteristic lines correspond to the following in the second coordinate system. Axis coordinate values; for The corresponding first vector component; for The corresponding second vector component; for The corresponding third vector component; for The corresponding first vector component; for The corresponding second vector component; for The corresponding third vector component.

[0082] Optionally, step S105, which determines the extrinsic parameter calibration results of the laser scanning device through the position vector and attitude matrix, such as... Figure 7 As shown, it includes: Step S701: Obtain the rotation vector corresponding to the attitude matrix.

[0083] The correspondence between the feature lines and the laser stripes in the first and second coordinate systems is as follows: Figure 8 As shown, specifically, the attitude matrix can be parameterized into a rotation vector through transformation.

[0084] Step S702: Determine the initial values ​​of the external parameters corresponding to the laser scanning device through the rotation vector and the position vector.

[0085] Integrate the rotation vector and position vector into The form is determined and set as the initial value of the external parameters corresponding to the laser scanning equipment. Among them, The vector to be determined is the vector corresponding to the position vector; Let be the vector to be determined corresponding to the rotation vector.

[0086] Step S703: Construct the fitness function and residual function corresponding to the laser scanning device based on the initial values ​​of the external parameters, position parameters, direction parameters, and intersection parameters.

[0087] Optionally, the fitness function is: ; The residual function is: ; in, The fitness function; It is the residual function; The initial value corresponding to the feature line; This represents the current coordinate value corresponding to the feature line; The number of characteristic lines; This is the attitude matrix; It is a position vector; For the first The position parameters of each feature line in the first coordinate system; The first intersection point; For the first The direction parameters of each feature line in the first coordinate system; The vector to be determined is the vector corresponding to the position vector; Let be the vector to be determined corresponding to the rotation vector; This is the first external parameter solution.

[0088] Step S704: Use the particle swarm optimization algorithm to obtain the first extrinsic solution corresponding to the initial extrinsic values ​​under the fitness function.

[0089] The particle swarm optimization algorithm is used to search for a rough solution corresponding to the initial value of the extrinsic parameters under the fitness function, and this rough solution is used as the first extrinsic parameter solution.

[0090] Step S705: Use one or more of the above nonlinear optimization algorithms, such as gradient descent, Newton's method, quasi-Newton's method, conjugate gradient method, and interior point method, to obtain the second extrinsic solution corresponding to the first extrinsic solution of the residual function.

[0091] Then, one or more of the above nonlinear optimization algorithms, such as gradient descent, Newton's method, quasi-Newton's method, conjugate gradient method, and interior point method, are used to solve the residual function to obtain the second extrinsic solution corresponding to the first extrinsic solution.

[0092] Step S706: Determine the external parameter calibration result corresponding to the laser scanning equipment based on the second external parameter solution.

[0093] In layman's terms, position vector That is, the coordinates (x, y, z) of the origin of the object's own coordinate system in the reference coordinate system are used in the solution vector. Reference; attitude vector It can characterize the orientation of the three coordinate axes X, Y, and Z of the object's own coordinate system in the reference coordinate system, and can be used to describe the object's orientation. It has a total of 9 parameters, which can be parameterized into a three-dimensional vector through the Rodrigues transformation, and used in the solution vector. Refers to. The final solution result is the external parameter, which can be used as the external parameter calibration result.

[0094] As can be seen from the above calibration control method for laser scanning equipment, this method uses a special calibration block with protrusions to calibrate the laser scanning equipment, and the calibration of external parameters can be completed with only one acquisition, simplifying the operation process; this method uses the intersection of the feature lines of the calibration block and the laser plane of the laser scanning equipment to realize the calibration control process, and there are no requirements on the direction and length of the feature lines, as long as the laser stripes can cover several feature lines, thus improving the calibration accuracy.

[0095] Corresponding to the above embodiments of the calibration control method for laser scanning equipment, this invention also provides a calibration control system for laser scanning equipment, such as... Figure 9 As shown, the system includes: An initialization module 910 is used to acquire a calibration block associated with a laser scanning device; wherein, the protruding surface of the calibration block is provided with multiple reflective units; The feature line processing module 920 is used to determine the feature line corresponding to the calibration block based on the intersection line between adjacent reflection units, and to determine the position parameters and direction parameters corresponding to the feature line using the first coordinate system corresponding to the calibration block; The laser irradiation control module 930 is used to control the laser scanning device to project a laser plane onto the reflective unit using preset scanning parameters when the calibration block is detected to be placed at the corresponding calibration position of the laser scanning device, and to acquire the laser stripes formed on the surface of the reflective unit in real time. The calibration parameter determination module 940 is used to determine the intersection parameters of the feature line and the laser stripe using the second coordinate system corresponding to the laser scanning device, and to calculate the position vector and attitude matrix corresponding to the first coordinate system and the second coordinate system using the position parameters, direction parameters and intersection parameters; The calibration execution control module 950 is used to determine the external parameter calibration results of the laser scanning equipment through position vectors and attitude matrices.

[0096] As can be seen from the above-mentioned calibration control system for laser scanning equipment, the system uses a special calibration block with protrusions to calibrate the laser scanning equipment. The calibration of external parameters can be completed with only one acquisition, simplifying the operation process. The system uses the intersection of the feature lines of the calibration block and the laser plane of the laser scanning equipment to realize the calibration control process. There are no requirements on the direction and length of the feature lines. It is only necessary for the laser stripes to cover a number of feature lines, which improves the calibration accuracy.

[0097] The calibration control system for laser scanning equipment provided in this embodiment of the invention has the same implementation principle and technical effect as the aforementioned calibration control method embodiment for laser scanning equipment. For the sake of brevity, any parts not mentioned in the system embodiment can be referred to the corresponding content in the aforementioned calibration control method embodiment for laser scanning equipment.

[0098] This embodiment also provides an electronic device, the structural schematic diagram of which is shown below. Figure 10 As shown, the device includes a processor 101 and a memory 102; wherein the memory 102 is used to store one or more computer instructions, which are executed by the processor to implement the steps of the calibration control method for the laser scanning device described above.

[0099] Figure 10 The electronic device shown also includes a bus 103 and a communication interface 104, with the processor 101, communication interface 104 and memory 102 connected via the bus 103.

[0100] The memory 102 may include high-speed random access memory (RAM) and may also include non-volatile memory, such as at least one disk storage device. The bus 103 may be an ISA bus, PCI bus, or EISA bus, etc. The bus can be divided into address bus, data bus, control bus, etc. For ease of representation, Figure 10 The symbol is represented by a single double-headed arrow, but this does not mean that there is only one bus or one type of bus.

[0101] The communication interface 104 is used to connect to at least one user terminal and other network units through a network interface, and to send encapsulated IPv4 packets or IPv4 packets to the user terminal through the network interface.

[0102] Processor 101 may be an integrated circuit chip with signal processing capabilities. In implementation, each step of the above method can be completed by the integrated logic circuitry in the hardware of processor 101 or by instructions in software form. The processor 101 can be a general-purpose processor, including a Central Processing Unit (CPU), a Network Processor (NP), etc.; it can also be a Digital Signal Processor (DSP), an Application Specific Integrated Circuit (ASIC), a Field-Programmable Gate Array (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, or discrete hardware components. It can implement or execute the methods, steps, and logic block diagrams disclosed in the embodiments of this disclosure. The general-purpose processor can be a microprocessor or any conventional processor. The steps of the methods disclosed in the embodiments of this disclosure can be directly manifested as execution by a hardware decoding processor, or execution by a combination of hardware and software modules in the decoding processor. The software module can reside in a mature storage medium in the art, such as random access memory, flash memory, read-only memory, programmable read-only memory, electrically erasable programmable memory, or registers. This storage medium is located in memory 102. The processor 101 reads the information in memory 102 and, in conjunction with its hardware, completes the steps of the method described in the foregoing embodiments.

[0103] This invention also provides a storage medium storing a computer program, which, when executed by a processor, performs the steps of the calibration control method for a laser scanning device described in the foregoing embodiments.

[0104] In the several embodiments provided in this application, it should be understood that the disclosed systems, apparatuses, devices, and methods can be implemented in other ways. The system embodiments described above are merely illustrative. For example, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. Furthermore, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Additionally, the coupling or direct coupling or communication connection shown or discussed may be through some communication interfaces; the indirect coupling or communication connection between devices or units may be electrical, mechanical, or other forms.

[0105] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0106] In addition, the functional units in the various embodiments of the present invention can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit.

[0107] If the aforementioned functions are implemented as software functional units and sold or used as independent products, they can be stored in a processor-executable, non-volatile, computer-readable storage medium. Based on this understanding, the technical solution of this invention, essentially, or the part that contributes to the prior art, or a portion of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, electronic device, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0108] Finally, it should be noted that the above-described embodiments are merely specific implementations of the present invention, used to illustrate the technical solutions of the present invention, and not to limit it. The scope of protection of the present invention is not limited thereto. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that any person skilled in the art can still modify or easily conceive of changes to the technical solutions described in the foregoing embodiments within the technical scope disclosed in the present invention, or make equivalent substitutions for some of the technical features; and these modifications, changes, or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention, and should all be covered within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A calibration control method for a laser scanning device, characterized by, The method comprises: acquiring a calibration block associated with a laser scanning device; wherein a protruding part surface of the calibration block is provided with a plurality of reflection units; determining a feature line corresponding to the calibration block based on intersection lines between adjacent reflection units, and determining position parameters and direction parameters corresponding to the feature line by using a first coordinate system corresponding to the calibration block; when detecting that the calibration block is placed at a calibration position corresponding to the laser scanning device, controlling the laser scanning device to project a laser plane to the reflection units by using preset scanning parameters, and acquiring laser stripes formed by surfaces of the reflection units in real time; determining intersection parameters of the feature line and the laser stripes by using a second coordinate system corresponding to the laser scanning device, and calculating position vectors and attitude matrices corresponding to the first coordinate system and the second coordinate system by using the position parameters, the direction parameters and the intersection parameters; determining an external parameter calibration result corresponding to the laser scanning device by using the position vectors and the attitude matrices.

2. The calibration control method for a laser scanning device according to claim 1, wherein, The step of determining a feature line corresponding to the calibration block based on intersection lines between adjacent reflection units, and determining position parameters and direction parameters corresponding to the feature line by using a first coordinate system corresponding to the calibration block, comprises: acquiring a first coordinate system corresponding to the calibration block, and acquiring reflection planes corresponding to each reflection unit based on the first coordinate system; determining intersection lines between adjacent reflection planes corresponding to adjacent reflection units, and determining a feature line corresponding to the calibration block based on the intersection lines; acquiring coordinate values and direction values corresponding to target points in the feature line, and determining the position parameters and the direction parameters corresponding to the coordinate values and the direction values based on the first coordinate system.

3. The calibration control method for a laser scanning device according to claim 1, wherein The step of, when detecting that the calibration block is placed at a calibration position corresponding to the laser scanning device, controlling the laser scanning device to project a laser plane to the reflection units by using preset scanning parameters, and acquiring laser stripes formed by surfaces of the reflection units in real time, comprises: determining a preset calibration position in the laser scanning device, and acquiring a position sensor and an image sensor corresponding to the calibration position; wherein the calibration position is located in a laser irradiation region of the laser scanning device; when detecting that the calibration block is placed at the calibration position by using the position sensor, determining a line-scan laser triggering instruction corresponding to the laser scanning device and a laser plane corresponding thereto by using preset scanning parameters; controlling the laser scanning device to project the laser plane to the reflection units corresponding to the calibration block according to the line-scan laser triggering instruction; acquiring laser stripes formed by surfaces of the reflection units in the protruding part in real time by using the image sensor.

4. The calibration control method for a laser scanning device according to claim 1, wherein The step of determining intersection parameters of the feature line and the laser stripes by using a second coordinate system corresponding to the laser scanning device, comprises: acquiring a second coordinate system corresponding to the laser scanning device; determining a first plane and a second plane corresponding to adjacent reflection units corresponding to the feature line, acquiring a first laser stripe corresponding to the first plane and a second laser stripe corresponding to the second plane; acquire a first linear expression corresponding to the first laser stripe and a second linear expression corresponding to the second laser stripe based on the second coordinate system respectively; calculate and acquire a first intersection point of the feature line and the laser stripe by using the first linear expression and the second linear expression; determine an intersection parameter of the feature line and the laser stripe according to a coordinate parameter of the first intersection point in the second coordinate system.

5. The calibration control method for a laser scanning device according to claim 4, wherein calculate a position vector and an attitude matrix corresponding to the first coordinate system and the second coordinate system by using the position parameter, the direction parameter and the intersection parameter, including: determine a first linear feature corresponding to the feature line according to plane feature data corresponding to the first plane and the second plane; convert the first linear feature from the first coordinate system to the second coordinate system based on the position parameter and the direction parameter to obtain a second linear feature corresponding to the feature line, and determine a second intersection point by using the second linear feature and the intersection parameter corresponding to the laser plane; acquire deviation data between the observation data and the prediction data by taking the first intersection point as the observation data and taking the second intersection point as the prediction data; determine a position vector and an attitude matrix corresponding to the first coordinate system and the second coordinate system by using the deviation data.

6. The calibration control method for a laser scanning device according to claim 5, wherein The position vector and the attitude matrix satisfy the following relationship: ； ； wherein, is a start value corresponding to the feature line; is a current coordinate value corresponding to the feature line; is the second linear feature corresponding to the th feature line; is the first linear feature corresponding to the th feature line; is the position parameter corresponding to the th feature line in the second coordinate system; is the position parameter corresponding to the th feature line in the first coordinate system; is the direction parameter corresponding to the th feature line in the second coordinate system; is the direction parameter corresponding to the th feature line in the first coordinate system; is the pose matrix; is the position vector; is the second intersection point; is the first intersection point; is the laser plane; is the th feature line in the second coordinate system axis coordinate value; is the th feature line in the second coordinate system axis coordinate value; is the 1st vector component corresponding to; is the 2nd vector component corresponding to; is the 3rd vector component corresponding to; is the 1st vector component corresponding to; is the 2nd vector component corresponding to; is the 3rd vector component corresponding to.

7. The calibration control method for a laser scanning device according to claim 6, wherein The steps of determining an extrinsic calibration result corresponding to the laser scanning device by using the position vector and the attitude matrix include: acquire a rotation vector corresponding to the attitude matrix; determine an initial value of the extrinsic parameter corresponding to the laser scanning device by using the rotation vector and the position vector; construct an adaptive function and a residual function corresponding to the laser scanning device according to the initial value of the extrinsic parameter, the position parameter, the direction parameter and the intersection parameter respectively; acquire a first extrinsic parameter solution corresponding to the initial value of the extrinsic parameter under the adaptive function by using a particle swarm algorithm; acquire a second extrinsic parameter solution corresponding to the first extrinsic parameter solution by using one or more of the following nonlinear optimization algorithms: gradient descent method, Newton method, quasi-Newton method, conjugate gradient method and interior point method; determine an extrinsic calibration result corresponding to the laser scanning device based on the second extrinsic parameter solution.

8. The calibration control method for a laser scanning device according to claim 7, wherein, The adaptive function is: ； The residual function is: ； in, The fitness function is... The residual function is... The starting value corresponding to the feature line; The current coordinate value corresponding to the feature line; The number of the feature lines; The attitude matrix; The position vector; For the first The position parameters of the feature lines in the first coordinate system; This is the first intersection point; For the first The direction parameters of the feature lines in the first coordinate system; The vector to be determined is the vector corresponding to the position vector; The vector to be determined is the vector corresponding to the rotation vector; This is the solution for the first external parameter.

9. A calibration control system for a laser scanning device, characterized by The system includes: An initialization module is configured to acquire a calibration block associated with a laser scanning device, wherein a protruding part surface of the calibration block is provided with a plurality of reflection units. A feature line processing module is configured to determine a feature line corresponding to the calibration block based on an intersection line between adjacent reflection units, and determine a position parameter and a direction parameter of the feature line by using a first coordinate system corresponding to the calibration block. A laser irradiation control module is configured to control the laser scanning device to project a laser plane to the reflection units by using a preset scanning parameter when it is detected that the calibration block is placed at a calibration position corresponding to the laser scanning device, and acquire laser stripes formed by surfaces of the reflection units in real time. The calibration parameter determination module is configured to determine an intersection parameter of the feature line and the laser stripe by using a second coordinate system corresponding to the laser scanning device, and to calculate a position vector and an attitude matrix corresponding to the first coordinate system and the second coordinate system by using the position parameter, the direction parameter and the intersection parameter. The calibration execution control module is configured to determine an external parameter calibration result corresponding to the laser scanning device by using the position vector and the attitude matrix.

10. An electronic device, comprising: The electronic device comprises a processor and a memory, and the memory stores computer executable instructions capable of being executed by the processor. The processor executes the computer executable instructions to implement the steps of the calibration control method for the laser scanning device according to any one of claims 1 to 8.

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