A linear laser gear measurement sensor space pose optimization method

Abstract

The line laser gear measurement sensor space pose optimization method of the application comprises: generating tooth surface sampling points and tooth surface unit normal vectors in a gear coordinate system; transforming the tooth surface sampling points and tooth surface unit normal vectors to a line laser coordinate system; establishing an effective field of view model of the line laser sensor in the line laser coordinate system; selecting effective sampling points from the tooth surface sampling points in the line laser coordinate system that meet the preset measurement feasible conditions; calculating the included angle between the measurement direction and the tooth surface unit normal vector corresponding to the effective sampling points; constructing a space pose evaluation cost function; iteratively optimizing the candidate space pose parameter group within the preset parameter range to obtain the optimal sensor space pose parameter group; and determining the space pose parameter range of the line laser sensor. The application can determine the space pose parameter range of the line laser sensor according to the key geometric parameters of the gear and the line laser measurement system parameters, so as to improve the measurement quality, measurement stability and measurement efficiency.

Description

Technical Field

[0001] This application relates to the field of gear measurement technology, and in particular to a method for optimizing the spatial pose of a line laser gear measurement sensor. Background Technology

[0002] The measurement results of gear tooth surfaces directly affect the evaluation of gear meshing errors and the analysis of transmission performance. Line laser measurement can achieve non-contact measurement of gear surfaces. However, in practical applications, it has been found that the inter-tooth structure of gears can cause adjacent teeth to obstruct each other, making some tooth surfaces invisible or poorly visible from a single viewing angle. Moreover, the measurement quality changes significantly with the direction of the laser beam. When the beam direction is poor, a large number of invalid measurement points are generated, affecting the measurement quality. In addition, different gear parameters can lead to significant differences in the normal distribution of the tooth surface. Line laser sensors use a fixed posture, which is not universal. On-site posture adjustment often requires repeated experiments, which is time-consuming and affects measurement efficiency. Furthermore, it is difficult to adjust to a suitable posture, affecting measurement stability. Summary of the Invention

[0003] This application aims to address at least one of the technical problems existing in the prior art. To this end, this application proposes a spatial pose optimization method for a line laser gear measurement sensor, which can automatically evaluate candidate poses and output the spatial pose parameter range of the line laser sensor based on the key geometric parameters of the gear and the parameters of the line laser measurement system, thereby improving measurement quality, measurement stability, and measurement efficiency.

[0004] The spatial pose optimization method for a line laser gear measurement sensor according to embodiments of this application includes: Obtain the key geometric parameters of the gear, establish a gear tooth surface geometric model based on the key geometric parameters, and generate tooth surface sampling points and corresponding tooth surface unit normal vectors in the gear coordinate system; Based on the candidate spatial pose parameter set of the line laser sensor, the tooth surface sampling points and tooth surface unit normal vector in the gear coordinate system are transformed to the line laser coordinate system. The candidate spatial pose parameter set includes at least rotation parameters, translation parameters and gear phase angle. Acquire the parameters of the line laser measurement system and establish an effective field-of-view model of the line laser sensor in the line laser coordinate system; Based on the effective field-of-view model, effective sampling points that meet the preset measurement feasibility conditions are selected from the tooth surface sampling points in the line laser coordinate system. Using the opposite direction of the laser beam direction corresponding to the effective sampling point as the measurement direction, calculate the angle between the measurement direction and the unit normal vector of the tooth surface of the effective sampling point in the linear laser coordinate system; Construct the spatial pose evaluation cost function of the line laser sensor, and calculate the cost function value of each candidate spatial pose parameter group; Based on the cost function value, the candidate spatial pose parameter set is iteratively optimized within a preset parameter range to obtain the optimal sensor spatial pose parameter set. Based on the optimal sensor spatial pose parameter set, the spatial pose parameter range of the line laser sensor is determined, wherein the cost function value corresponding to the spatial pose parameter range is less than or equal to the cost function value corresponding to the optimal sensor spatial pose parameter set plus a preset tolerance value.

[0005] The spatial pose optimization method for the line laser gear measurement sensor according to the embodiments of this application has at least the following beneficial effects: In this application, a gear tooth surface geometric model is established through key geometric parameters. Based on the candidate spatial pose parameter group of the line laser sensor, the tooth surface sampling points and tooth surface unit normal vector in the gear coordinate system are transformed to the line laser coordinate system. Then, according to the parameters of the line laser measurement system, an effective field-of-view model of the line laser sensor is established in the line laser coordinate system. Based on the effective field-of-view model, effective sampling points that meet the preset measurement feasibility conditions are selected from the tooth surface sampling points. Then, through spatial pose evaluation and optimization, the recommended range of spatial pose parameters of the line laser sensor is obtained, which greatly improves the measurement quality, measurement stability and measurement efficiency.

[0006] According to some embodiments of this application, generating tooth surface sampling points in the gear coordinate system includes: The tooth profile curve is parameterized using the involute parameters of the gear, and the gear tooth surface is extended along the tooth width direction to obtain a parameterized representation of the tooth surface. A two-dimensional sampling grid is established in the involute parameter direction and the tooth width direction to sample the gear tooth surface, thereby obtaining the tooth surface sampling points in the gear coordinate system.

[0007] According to some embodiments of this application, the candidate spatial pose parameter set Represented as: , in, The rotational parameters of the line laser sensor relative to the gear coordinate system are... The translation parameter of the line laser sensor relative to the gear coordinate system. The gear phase angle; For the coordinates of any tooth surface sampling point in the gear coordinate system coordinates in the linear laser coordinate system Represented as: , in, The rotation matrix is ​​constructed using the rotation parameters. The translation matrix is ​​constructed using the translation parameters; For the unit normal vector of the tooth surface in the gear coordinate system The vector in the line laser coordinate system Represented as: .

[0008] According to some embodiments of this application, establishing the effective field-of-view model of the line laser sensor in the line laser coordinate system includes: An original field-of-view model of the line laser sensor is established in the line laser coordinate system, and the original field-of-view model represents the theoretical effective measurement area of ​​the line laser sensor. The original field-of-view model is subjected to lateral shrinking and vertical bottom raising to obtain the effective field-of-view model.

[0009] According to some embodiments of this application, the preset measurement feasibility conditions include visibility conditions, which include: Obtain the center point of the tip surface of each tooth of the gear, remove the teeth whose center point of the tip surface is located outside the effective field of view model, and then place them in the linear laser coordinate system. Next, remove the center point of the tooth tip surface. Coordinates less than the center point of the gear The coordinates of the gear teeth are used to obtain the target gear teeth; When the center point of the tooth tip surface of the target tooth is located in the linear laser coordinate system When the target tooth is in the negative side region of the shaft, the right tooth surface of the target tooth is selected as the target tooth surface; When the center point of the tooth tip surface of the target tooth is located in the linear laser coordinate system When the target tooth is in the positive side region of the shaft, the left tooth surface of the target tooth is selected as the target tooth surface; The tooth surface sampling points on the target tooth surface are selected to form the first sampling point set.

[0010] According to some embodiments of this application, the preset measurement feasibility conditions further include occlusion conditions, which include: The linear laser coordinate system is defined by the discrete arrangement of the multiple emitter units of the linear laser sensor. Axial direction; In the linear laser coordinate system, select the tooth surface sampling point on the target tooth surface. The position of the transmitter unit with the smallest distance in the axial direction is taken as the position of the transmitter unit corresponding to the tooth surface sampling point on the target tooth surface; Obstruction determination feature points are obtained on the target tooth surface. The obstruction determination feature points are the intersection points of the cylindrical surface of the tooth profile control circle and the tooth profile curve. The tooth apex of the adjacent tooth of the target tooth is obtained. The tooth apex is the intersection point of the tooth tip circle and the tooth profile curve, and is located on the side of the target tooth closer to the corresponding transmitter unit position. The obstruction determination feature points, the tooth apex, and the center point of the tooth tip surface are located on the same plane perpendicular to the axis of the gear. The occlusion determination feature point, the tooth vertex, and the emitter unit position are projected onto the linear laser coordinate system. In the plane, an incident beam vector of the laser beam is constructed based on the projection points of the transmitter unit position and the tooth apex. A comparison vector is constructed based on the projection points of the transmitter unit position and the occlusion determination feature points. The incident beam vector and the comparison vector are then compared. Two-dimensional cross product in a plane; Based on the positive or negative value of the two-dimensional cross product, it is determined that the occlusion determination feature point is located on the side of the corresponding laser beam. The feature point located on the side of the corresponding laser beam is then discarded if the target tooth is located in the linear laser coordinate system. Different target tooth surfaces on the sides of the shaft; If the occlusion determination feature point is located laterally to the corresponding laser beam and the target gear tooth is located in the linear laser coordinate system... If the lateral orientation of the shafts is the same, then determine whether the absolute value of the two-dimensional cross product is greater than a preset cross product tolerance threshold, and discard the target tooth surface whose absolute value of the two-dimensional cross product is less than or equal to the preset cross product tolerance threshold. Remove the tooth surface sampling points of the target tooth surface from the first sampling point set to obtain the second sampling point set.

[0011] According to some embodiments of this application, the preset measurement feasibility conditions further include field of view conditions, which include: Determine whether the tooth surface sampling points in the second sampling point set are within the field of view defined by the effective field of view model, and remove the tooth surface sampling points located outside the field of view defined by the effective field of view model to obtain a third sampling point set including the effective sampling points.

[0012] According to some embodiments of this application, the step of constructing the spatial pose evaluation cost function of the line laser sensor and calculating the cost function value of each candidate spatial pose parameter group includes: The ratio of the number of valid sampling points in the third sampling point set to the number of tooth surface sampling points in the second sampling point set is used as the field of view coverage rate, and the complement number of the field of view coverage rate is used as the field of view coverage penalty value. The valid sampling points with an included angle greater than a preset angle threshold are taken as bad points, and the ratio of the number of bad points to the number of valid sampling points is calculated to obtain the ratio of angle non-compliance points. Calculate the ratio of the included angle corresponding to the bad point to the preset angle threshold to obtain the angle exceeding the threshold value; Multiple bad points are arranged in the direction of involute parameters and tooth width to form a bad point binary matrix. The bad point binary matrix is ​​convolved by a multi-scale convolution kernel to calculate several local bad point density response values. When at least one of the local bad point density response values ​​exceeds the corresponding response threshold, the maximum value among the ratios of the local bad point density response value to the corresponding response threshold is taken as the cluster penalty value. The single-tooth surface cost is obtained by summing the field coverage penalty value, the ratio of angle non-compliant points, the angle exceeding the threshold amplitude value, and the clustering penalty value according to the first preset weighting. The mass cost is obtained by summing the worst and average values ​​of all the single tooth surface cost values ​​according to the second preset weighting. The evaluation value is obtained by summing the ratio of the field coverage rate and the effective sampling points whose included angle is less than or equal to the preset angle threshold according to the third preset weighting. When the evaluation value is less than the preset reference value, a quantity penalty value is introduced. The cost function value is obtained by summing the quality cost value and the quantity penalty value according to the fourth preset weighting.

[0013] According to some embodiments of this application, the step of iteratively optimizing the candidate spatial pose parameter set within a preset parameter range based on the cost function value to obtain the optimal sensor spatial pose parameter set includes: Calculate the cost function value corresponding to the parameters of each candidate spatial pose parameter group, and select the candidate spatial pose parameter group with the smallest cost function value as the optimal sensor spatial pose parameter group.

[0014] According to some embodiments of this application, determining the spatial pose parameter range of the line laser sensor based on the optimal sensor spatial pose parameter set includes: The parameters in the optimal sensor spatial pose parameter set are divided into target parameters and constraint parameters; The range of values ​​for the target parameter is obtained by a two-stage search, which includes a coarse scan search and a fine scan search. The search step size of the coarse scan search is larger than that of the fine scan search. The coarse scan search determines a local candidate region within a preset area, and the fine scan search determines the range of values ​​for the target parameter within the local candidate region. The range of values ​​for the constraint parameters is obtained by searching within the neighborhood of the optimal sensor spatial pose parameter set. The spatial pose parameter range is obtained based on the value range of the target parameter and the value range of the constraint parameter.

[0015] Other features and advantages of this application will be set forth in the following description, and will be apparent in part from the description, or may be learned by practicing this application. Attached Figure Description

[0016] The above and / or additional aspects and advantages of this application will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which: Figure 1 This is a flowchart illustrating the spatial pose optimization method for the line laser gear measurement sensor of this application. Figure 2 A schematic diagram of the gear tooth surface geometry model constructed for this application; Figure 3 This is a schematic diagram of the gear tooth surface after being filtered by visibility criteria in this application; Figure 4 A schematic diagram for determining the occlusion condition of the gear tooth surface in this application; Figure 5 This is a schematic diagram showing the location of one of the occlusion determination feature points, the corresponding tooth vertex, and the corresponding emitter unit position; Figure 6 A schematic diagram of the tooth surface when the line laser sensor of this application is configured with the optimal spatial pose parameters. Detailed Implementation

[0017] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0018] It should be noted that although functional modules are divided in the device schematic diagram and a logical order is shown in the flowchart, in some cases, the steps shown or described may be performed in a different order than the module division in the device or the order in the flowchart. The terms "first" and "second," etc., in the specification, claims, and the aforementioned drawings are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence.

[0019] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein is for the purpose of describing embodiments of this application only and is not intended to limit this application.

[0020] The following is for reference. Figures 1 to 6 This application describes a method for optimizing the spatial pose of a line laser gear measurement sensor according to embodiments thereof.

[0021] refer to Figure 1 As shown, the spatial pose optimization method for a line laser gear measurement sensor according to an embodiment of this application includes, but is not limited to, the following steps: S100. Obtain the key geometric parameters of the gear, establish a gear tooth surface geometric model based on the key geometric parameters, and generate tooth surface sampling points and corresponding tooth surface unit normal vectors in the gear coordinate system. S200, a candidate spatial pose parameter set based on a line laser sensor, transforms the tooth surface sampling points and tooth surface unit normal vector in the gear coordinate system to the line laser coordinate system. The candidate spatial pose parameter set includes at least rotation parameters, translation parameters, and gear phase angle. S300. Obtain the parameters of the line laser measurement system and establish an effective field-of-view model of the line laser sensor in the line laser coordinate system. S400. Based on the effective field-of-view model, select effective sampling points from the tooth surface sampling points in the line laser coordinate system that meet the preset measurement feasibility conditions. S500, Taking the opposite direction of the laser beam direction corresponding to the effective sampling point as the measurement direction, calculate the angle between the measurement direction and the unit normal vector of the tooth surface of the effective sampling point in the laser coordinate system. S600: Construct the spatial pose evaluation cost function for the line laser sensor and calculate the cost function value for each candidate spatial pose parameter group; S700: Based on the cost function value, iteratively optimize the candidate spatial pose parameter set within the preset parameter range to obtain the optimal sensor spatial pose parameter set; S800. Based on the optimal sensor spatial pose parameter set, determine the range of spatial pose parameters of the line laser sensor, wherein the cost function value corresponding to the range of spatial pose parameters is less than or equal to the cost function value corresponding to the optimal sensor spatial pose parameter set plus a preset tolerance value.

[0022] The spatial pose optimization method for a line laser gear measurement sensor in this application establishes a gear tooth surface geometric model through key geometric parameters. Based on the candidate spatial pose parameter group of the line laser sensor, the tooth surface sampling points and tooth surface unit normal vector in the gear coordinate system are transformed to the line laser coordinate system. Then, according to the parameters of the line laser measurement system, an effective field-of-view model of the line laser sensor is established in the line laser coordinate system. Based on the effective field-of-view model, effective sampling points that meet the preset measurement feasibility conditions are selected from the tooth surface sampling points. Finally, through spatial pose evaluation and optimization, the recommended spatial pose parameter range of the line laser sensor is obtained, which greatly improves the measurement quality, measurement stability and measurement efficiency.

[0023] The following is a detailed description of the spatial pose optimization method for the line laser gear measurement sensor proposed in this application.

[0024] In some embodiments of this application, step S100, obtaining the key geometric parameters of the gear, establishing a gear tooth surface geometric model based on the key geometric parameters, and generating tooth surface sampling points and corresponding tooth surface unit normal vectors in the gear coordinate system, specifically includes the following steps: In this step, key geometric parameters of the gear under test are obtained, including the number of teeth, module, tooth width, and pressure angle. If the gear under test is a helical gear, the helix angle can be further obtained, along with parameters such as the displacement coefficient and addendum coefficient used to describe non-standard gears. Gear coordinate system. of direction and The direction can be radial, with the tooth width direction aligned with the gear's axis, corresponding to the gear coordinate system. direction.

[0025] The gear tooth surface geometric model can be an involute tooth surface model. Based on the involute parametric equations and combined with key geometric parameters, the gear tooth surface geometric model is established. The gear tooth surface geometric model is as follows: Figure 2 As shown. Specifically, the tooth profile curve is parameterized with involute parameter u within the gear end face, and along the tooth width direction. The gear tooth surface is extended to obtain a parameterized representation of the tooth surface. , where b is the tooth width value.

[0026] A two-dimensional sampling grid is established in the involute parameter direction and the tooth width direction. The gear tooth surface is sampled to obtain the gear coordinate system. Coordinates of the sampling points on the tooth surface The set of and its corresponding tooth surface unit normal vector The set. Among them, for the gear coordinate system Each tooth surface sampling point below, based on Taking partial derivatives with respect to u and v respectively yields two tangent vectors. After calculating the tooth surface normal vector using the cross product and normalizing, the gear coordinate system is obtained. Unit normal vector of the tooth surface .

[0027] In some embodiments of this application, the sampling grid can be a uniform grid, with a preset step size in both the involute parameter direction and the tooth width direction. and The step size is determined based on the gear measurement resolution requirements and the spatial resolution of the line laser sensor. For example, It can be 0.004mm. It can be 0.001mm.

[0028] In some embodiments of this application, step S200, based on the candidate spatial pose parameter group of the line laser sensor, converts the gear coordinate system... Coordinates of the sampling points on the tooth surface and tooth surface unit normal vector Transform to linear laser coordinate system The parameters for each candidate spatial pose parameter group include at least rotation parameters, translation parameters, and gear phase angles, specifically including the following steps: In some embodiments of this application, a candidate spatial pose parameter group is provided. for: , in, For the line laser sensor relative to the gear coordinate system rotation parameters, For the line laser sensor relative to the gear coordinate system Translation parameters, The gear phase angle is used to describe the gear's position around its axis (i.e., ...). The rotation angle of the axis.

[0029] Based on candidate spatial pose parameter set The gear coordinate system can be determined. With line laser coordinate system The spatial pose relationship between them is determined, and a coordinate transformation formula is constructed.

[0030] For the gear coordinate system Coordinates of any tooth surface sampling point Its online laser coordinate system coordinates in It can be calculated using the following coordinate transformation relationship: ; Among them, through rotation parameters Construct rotation matrix By translation parameters Construct translation vector ; In some embodiments of this application, for the gear coordinate system Unit normal vector of the tooth surface Unit normal vector of tooth surface in online laser coordinate system Represented as: ; The gear coordinate system can be transformed using the above coordinate transformation. Coordinates of the sampling points on the tooth surface The set of and the corresponding unit normal vector of the tooth surface The set is uniformly transformed into the linear laser coordinate system. This provides a unified spatial reference for subsequent field of view determination, occlusion determination, and measurement angle calculation.

[0031] In some embodiments of this application, step S300 involves obtaining the parameters of the line laser measurement system and establishing the line laser coordinate system. The following steps are involved in establishing the effective field-of-view model for the linear laser sensor: In some embodiments of this application, parameters of the line laser measurement system are obtained. These parameters may include the reference distance, effective measurement width, effective measurement height, and shrinkage parameters related to safety margin of the line laser measurement system.

[0032] In some embodiments of this application, an online laser coordinate system Establish the original field of view model Original field of view model Used to characterize the theoretically effective measurement area of ​​a line laser sensor without a safety margin. Original field-of-view model. It can be defined by the horizontal boundary, the vertical boundary, and the working distance. For example, it can be represented as a set of points that satisfy the following boundary constraints: Horizontal boundary: ; Vertical boundary: ; Baseline distance: .

[0033] In some implementations, the original field-of-view model The shape can be trapezoidal or rectangular. Furthermore, to improve the stability of field-of-view edge region determination and reduce false edge detections, a model based on the original field-of-view is used. Perform safety edge reduction processing to obtain the effective field-of-view model of the line laser. Safety edge reduction treatment includes horizontal edge reduction and vertical bottom lifting.

[0034] Among them, the horizontal shrinkage refers to the amount of horizontal shrinkage introduced to the horizontal boundary. Horizontal shrinkage amount It can be the original field of view model The lateral dimension is 0.05 times or other suitable multiple, so that the effective lateral boundary becomes: Longitudinal elevation refers to introducing a longitudinal elevation amount at the longitudinal boundary. Vertical lifting amount It can be the original field of view model The longitudinal dimension is 0.05 times or another suitable multiple to eliminate unstable regions near the boundary, thereby obtaining an effective field-of-view model. .

[0035] In some embodiments of this application, step S400, selecting effective sampling points from the tooth surface sampling points in the line laser coordinate system that meet the preset measurement feasibility conditions according to the effective field-of-view model, specifically includes the following steps: refer to Figure 3 In some embodiments of this application, the preset measurement feasibility conditions include visibility conditions. Visibility determination is performed on each tooth, and tooth surface sampling points corresponding to the tooth surfaces that meet the requirements are selected to form a first sampling point set.

[0036] Visibility conditions specifically include: For each gear tooth, a representative point representing its position is determined. This representative point is selected as the center point of the tooth tip surface. The tooth tip surface is the portion of the tooth surface enclosed by the tooth tip surface, which is the end face of the tooth facing away from the gear axis. The center point of the tooth tip surface is the center point of the tooth surface facing away from the gear axis. Based on the center point of the tooth tip surface and the center point of the gear, an online laser coordinate system is established. Visibility constraints are set based on the relative positional relationships to filter out gear teeth that meet the visibility conditions, and the tooth tip center point is determined using an online laser coordinate system. The orientation relationship below determines the target tooth surface for the gear teeth.

[0037] Specifically, for each tooth, take the vertices of the gear tooth surfaces on both sides of the tooth at the middle position of the tooth width, and solve for the midpoint of the line connecting the two vertices to obtain the center point of the tooth tip surface. Ensure that the center point of the tooth tip surface is within the effective field of view of the effective field of view model, and remove teeth whose center point of the tooth tip surface is outside the effective field of view model.

[0038] And using the online laser coordinate system with the center point of the tooth tip surface and the center point of the gear. The relative position is used as a visibility constraint. For example, only teeth whose center point on the tooth tip surface satisfies a preset half-space condition are retained. The preset half-space condition can be an online laser coordinate system. Below, the center point of the tooth tip The coordinates are greater than or equal to the center point of the gear. Coordinates, removing the center point of the tooth tip surface Coordinates less than the center point of the gear The coordinates of the gear teeth are used to obtain the final target gear teeth.

[0039] Furthermore, based on the online laser coordinate system of the center point of the tooth tip surface... Below The coordinate symbols of the shaft divide the position of the gear teeth into... negative side region of the axis or On the positive side of the shaft, when the gear teeth are located When the shaft is in the negative side region, the right tooth surface of the gear tooth is selected as the target tooth surface. When the gear tooth is located in... When the shaft is in the positive side region, the left tooth surface of the gear tooth is selected as the target tooth surface, and the tooth surface sampling points on the target tooth surface are selected to form the first sampling point set.

[0040] In this embodiment, by selecting target teeth and target tooth surfaces based on preset half-space conditions and left and right half-zone determination under candidate poses, on the one hand, tooth surface areas that are within the visible half-space of the line laser sensor and are more likely to fall into the effective field of view can be preferentially retained, reducing invalid calculations for invisible areas. On the other hand, the evaluation range of subsequent tooth occlusion determination and measurement angle prediction is limited to the effective tooth surface area, thereby reducing the computational load and misjudgment risk of subsequent occlusion determination and measurement angle prediction, improving the computational efficiency and evaluation stability of the iterative search optimization process, and helping to output a pose parameter range of the line laser sensor that is more in line with the actual measurement feasibility.

[0041] refer to Figure 4 and Figure 5 As shown, in some embodiments of this application, the preset measurement feasibility conditions also include occlusion conditions, performing occlusion determination on the target tooth surface of the target tooth, removing all tooth surface sampling points corresponding to the occluded target tooth surface from the first sampling point set, and obtaining the second sampling point set.

[0042] The specific occlusion conditions include: An incident geometry model is constructed, which includes a discrete model of the emitter array. This discrete model is built from the array distribution parameters of the line laser emitter of the line laser sensor. Specifically, the multiple emitter units of the line laser emitter of the line laser sensor can be arranged along the line laser coordinate system. of Discrete arrangement along the axis, with each emitter unit in an online laser coordinate system. The spatial position of the transmitter unit is determined by the array starting position, discrete spacing, and effective array length parameters. The tooth surface sampling points on the target tooth surface have different lateral positions along the axial direction. There is a correspondence between the lateral coordinates along the axis and the emission position of the corresponding laser beam. Based on this correspondence, for any sampling point on the target tooth surface, the laser beam is positioned in the online laser coordinate system. The horizontal coordinate below, i.e. The coordinates are determined by selecting the transmitter unit with the smallest lateral coordinate distance from the sampling point on the target tooth surface from the set of lateral positions of each transmitter unit. This position is then used as the transmitter unit position corresponding to that sampling point. .

[0043] In this embodiment, by modeling the line laser emitter of the line laser sensor as a discrete array composed of multiple emitter units, and selecting the corresponding emitter unit position according to the position of the tooth surface sampling point on the target tooth surface in the lateral direction, the spatial source and direction difference of the laser beam at different lateral positions can be more realistically characterized, reducing the measurement angle estimation deviation caused by approximating with light from only a single direction.

[0044] Furthermore, obtain the occlusion determination feature points of the target tooth surface. Occlusion determination feature points The intersection point of the cylindrical surface of the tooth profile control circle and the tooth profile curve is located on the cylindrical surface of the preset tooth profile control circle and can be obtained by solving the involute equation of the gear. The radius of the tooth profile control cylinder is determined by calculation of the key geometric parameters of the gear, and the axis of the tooth profile control cylinder coincides with the axis of the gear.

[0045] Furthermore, obtain the tooth vertices of the adjacent teeth of the target tooth. Among them, the tooth apex The point where the tooth tip circle intersects the tooth profile curve, and along the beam direction of the laser beam incident on the target tooth, is the tooth tip. Located on the side of the target tooth closest to the corresponding transmitter unit position, the transmitter unit position corresponding to the target tooth is the position of the transmitter unit that emits the laser beam toward that target tooth. Occlusion determination feature point. Tooth apex The center point of the tooth tip is located on the same plane perpendicular to the axis of the gear, and the center point of the gear is also located on this plane.

[0046] Furthermore, the occlusion determination feature points are analyzed. The lateral orientation of the corresponding laser beam within a preset judgment plane is determined, and the target tooth surface is determined to be unobstructed or obstructed based on preset lateral criteria. The preset judgment plane is a linear laser coordinate system. of flat.

[0047] Position of the transmitter unit The apex of adjacent teeth And the occlusion determination feature points of the target gear teeth Projected to The plane yields three projection points. Based on the transmitter unit location... The projection point and the tooth vertex The projection point constructs the incident beam vector of the laser beam. Incident beam vector It can be represented as: ; Based on the transmitter unit location Projection points and occlusion determination feature points Construct comparison vectors from projection points Comparison vectors It can be represented as: ; Calculate the incident beam vector Comparison vectors exist Two-dimensional cross product in a plane .

[0048] Furthermore, based on the sign of the two-dimensional cross product and according to a preset orientation convention, the occlusion feature points are determined. Located to the left or right of the corresponding laser beam, the preset orientation can be: if the two-dimensional cross product is positive, then the occlusion is determined as a feature point. Located to the right of the corresponding laser beam; if the two-dimensional cross product is negative, then the occlusion is determined as a feature point. Located to the left of the corresponding laser beam; The occlusion detection feature point is located in the lateral direction of the corresponding laser beam, and the target gear tooth is located in the linear laser coordinate system. of Different target tooth surfaces on the sides of the shaft; If the occlusion detection feature point is located laterally to the corresponding laser beam and the target gear tooth is located in the linear laser coordinate system... of If the lateral orientations of the axes are the same, then it is determined whether the absolute value of the two-dimensional cross product is greater than a preset cross product tolerance threshold. If the absolute value of the two-dimensional cross product is not greater than the preset cross product tolerance threshold, it is treated as occlusion, and target tooth surfaces whose absolute value of the two-dimensional cross product is less than or equal to the preset cross product tolerance threshold are removed to ensure the conservatism and stability of the occlusion determination. Remove the tooth surface sampling points of the target tooth surface that were rejected from the first sampling point set to obtain the second sampling point set.

[0049] refer to Figure 4 As shown, assuming the tooth numbers are arranged in a counter-clockwise direction: tooth occlusion determination is performed on the target tooth surface of the i-th tooth, and the cross-product tolerance threshold is set to 0.01. The occlusion condition determination of this application is specifically explained below with two embodiments.

[0050] For the linear laser coordinate system of For the gear teeth on the right side of the shaft, determine whether the left tooth surface of the tooth is occluded. First, obtain the occlusion determination feature points of the target tooth surface of the i-th tooth. And along the beam direction of the laser beam, obtain the tooth vertex of the adjacent tooth i+1 located upstream of the target tooth. Thus, the tooth apex is determined based on the incident geometry model. Corresponding transmitter unit position To the tooth apex Occlusion determination feature points Transmitter unit location Project to Plane, construct comparison vectors and the incident beam vector Calculate the two-dimensional cross product of the two. .

[0051] If the 2D cross product is positive, it indicates that the occlusion of the feature points is being determined. To the right of the corresponding laser beam, the absolute value of the two-dimensional cross product is compared to the cross product tolerance threshold. If the absolute value of the two-dimensional cross product is greater than the cross product tolerance threshold, it indicates that the target tooth surface is not occluded. If the absolute value of the two-dimensional cross product is less than or equal to the cross product tolerance threshold, it indicates that the target tooth surface is occluded, and the occluded target tooth surface is discarded. If the two-dimensional cross product is negative, it indicates that the occlusion determination feature point is missing. On the left side of the laser beam, if the target tooth surface is determined to be occluded, then there is no need to examine the relationship between the absolute value of the two-dimensional cross product and the cross product tolerance threshold. All sampling points corresponding to the occluded target tooth surface are removed from the first sampling point set to obtain the second sampling point set.

[0052] For the linear laser coordinate system of For the teeth on the left side of the shaft, determine whether the right tooth surface is occluded. First, obtain the occlusion determination feature points of the target tooth surface of the i-th tooth. And along the beam direction of the laser beam, obtain the tooth apex of the adjacent tooth i-1 located upstream of the target tooth. Thus, the tooth apex is determined based on the incident geometry model. Corresponding transmitter unit position To the tooth apex Occlusion determination feature points Transmitter unit location Project to Plane, construct comparison vectors and the incident beam vector Calculate the cross product of the two. .

[0053] If the two-dimensional cross product is negative, it indicates that the occlusion of the feature points is being determined. To the left of the laser beam, the absolute value of the two-dimensional cross product is compared to the cross product tolerance threshold. If the absolute value of the two-dimensional cross product is greater than the cross product tolerance threshold, it indicates that the target tooth surface is not occluded. If the absolute value of the two-dimensional cross product is less than or equal to the cross product tolerance threshold, it indicates that the target tooth surface is occluded, and the occluded target tooth surface is discarded. If the two-dimensional cross product is positive, it indicates that the occlusion determination feature point is... On the right side of the laser beam, if the target tooth surface is determined to be occluded, then there is no need to examine the relationship between the absolute value of the two-dimensional cross product and the cross product tolerance threshold. All tooth surface sampling points corresponding to the occluded target tooth surface are removed from the first sampling point set to obtain the second sampling point set.

[0054] In this embodiment, occlusion determination is performed on the target tooth surface of the target gear tooth by occlusion condition, and all tooth surface sampling points on the occluded target tooth surface are removed from the first sampling point set. In this way, invalid calculations on the occluded area can be reduced, the screening efficiency and screening effect of effective sampling points can be improved, the computational efficiency and evaluation stability of the iterative search optimization process can be further improved, and it is more helpful to output the pose parameter range of the line laser sensor that is more in line with the actual measurement feasibility.

[0055] In some embodiments of this application, the preset measurement feasibility conditions further include field of view conditions, which specifically include: Perform a field-of-view determination on the tooth surface sampling points in the second sampling point set. Determine whether the tooth surface sampling points in the second sampling point set are located within the field-of-view region defined by the effective field-of-view model. If the tooth surface sampling points in the second sampling point set are located within the field-of-view region defined by the effective field-of-view model, it is determined that the tooth surface sampling point satisfies the field-of-view condition. Tooth surface sampling points located outside the field-of-view region defined by the effective field-of-view model are removed, resulting in a third sampling point set including the effective sampling points.

[0056] In this embodiment, by using the field of view conditions, the sampling points on the target tooth surface are judged, and the sampling points on the tooth surface located outside the field of view area defined by the effective field of view model are eliminated. This can further improve the screening efficiency and effect of effective sampling points, further improve the computational efficiency and evaluation stability of the iterative search optimization process, and help to output a recommended pose parameter range that is more in line with the feasibility of actual measurement.

[0057] In some embodiments of this application, S500, the measurement direction is the opposite direction of the laser beam direction corresponding to the effective sampling point, and the online laser coordinate system is used. Next, calculate the unit normal vector of the tooth surface corresponding to the measurement direction and the effective sampling point. The included angle between them, the measurement direction and the unit normal vector of the tooth surface corresponding to the effective sampling point The included angle between them can be defined as the measuring angle. Specifically, it includes: First, for any valid sampling point in the third sampling point set, based on the online laser coordinate system of that valid sampling point... The coordinates below and the corresponding transmitter unit positions The coordinates are used to determine the direction vector in the opposite direction of the line laser beam direction corresponding to the effective sampling point through vector calculation. Furthermore, combining this effective sampling point with the online laser coordinate system... The corresponding unit normal vector of the tooth surface Calculate the direction vector With the unit normal vector of the tooth surface The included angle between them, i.e., the measuring angle : ; Measuring angles The spatial angular relationship between the laser beam and the tooth surface normal is characterized, reflecting the measurement quality at the effective sampling point. Generally speaking, the measurement angle... The smaller the value, the better the measurement quality.

[0058] In some embodiments of this application, S600 involves constructing a spatial pose evaluation cost function for the line laser sensor and calculating the cost function value for each candidate spatial pose parameter group, specifically including the following steps: For any candidate spatial pose parameter set For each target tooth surface, online laser coordinate system The generated valid sampling points are used to perform field of view determination, resulting in a set of points within the field of view. The ratio of points within the field of view is calculated, which is the ratio of the number of valid sampling points in the third sampling point set to the number of tooth surface sampling points in the second sampling point set. This ratio is used as the field of view coverage rate. The complement of the field of view coverage rate is used as the field of view coverage penalty value. The sum of the field of view coverage rate and the field of view coverage penalty value is 1. When the ratio of points within the field of view is lower than the preset minimum ratio, a larger penalty is applied to the cost function to eliminate unusable poses.

[0059] Furthermore, a preset angle threshold is set, and valid sampling points in the field of view where the measured angle exceeds the preset angle threshold are marked as bad points. The ratio of the number of bad points to the number of valid sampling points on the same target tooth surface is calculated to obtain the ratio of angle failure points. The preset angle threshold can be determined according to the characteristics of the actual line laser sensor. Different line laser sensors have different preset angle thresholds due to differences in their optical structure and imaging principle. Simultaneously, the ratio of the included angle corresponding to the defective pixel exceeding a preset angle threshold is calculated to obtain the angle exceeding the threshold amplitude value. For example, if the angle corresponding to the defective pixel exceeds the preset angle threshold by 20%, the corresponding angle exceeding the threshold amplitude value can be 0.2.

[0060] Furthermore, multiple defective pixels are arranged in a grid topology formed by the involute parameter direction and the tooth width direction to form a defective pixel binary matrix. A multi-scale convolution kernel is then used to convolve the defective pixel binary matrix to calculate several local defective pixel density response values. The multi-scale convolution kernel can be a clumping kernel, a lateral kernel, or a vertical kernel. For example, the defective pixel binary matrix of a clumping kernel can be 5×5, that of a lateral kernel can be 1×5, and that of a vertical kernel can be 9×1.

[0061] When at least one local bad pixel density response value exceeds the corresponding response threshold, the maximum value among the ratios of the local bad pixel density response value to the corresponding response threshold is taken as the clustering penalty value to characterize the risk of bad pixels clustering in a local area.

[0062] Furthermore, the single-tooth surface value is obtained by summing the field coverage penalty value, the ratio of angle non-compliant points, the angle exceeding the threshold amplitude value, and the clustering penalty value according to the first preset weighting.

[0063] The single-tooth-surface cost value of each target tooth surface is aggregated, that is, the worst value and the average value of all single-tooth-surface costs are summed according to the second preset weighting to obtain the quality cost value.

[0064] The evaluation value is obtained by summing the ratio of the field of view coverage to the effective sampling points whose measurement angle is less than or equal to the preset angle threshold according to the third preset weight. When the evaluation value is less than the preset reference value, a quantity penalty value is introduced.

[0065] Finally, the cost function value is obtained by summing the quality cost value and the quantity penalty value according to the fourth preset weighting, and is used as the evaluation result of the candidate spatial pose parameter group.

[0066] In this embodiment, by constructing and calculating the aforementioned cost function, a unified quality evaluation standard can be formed among candidate spatial poses, thereby guiding the optimization solution to obtain a better pose. This cost function, on the one hand, ensures that a sufficient proportion of the target tooth surface sampling points fall within the effective field of view of the line laser through field-of-view coverage penalty and minimum coverage constraint. On the other hand, it constrains the measurement angle distribution through preset angle threshold related indicators, ensuring that the measurement angle of the vast majority of tooth surface sampling points is less than the preset angle threshold, while allowing a small number of tooth surface sampling points to exceed the preset angle threshold, but limiting their proportion and the extent of exceeding the limit. Furthermore, the clustering penalty value calculated by multi-scale convolution kernels suppresses the clustering of bad points in local areas, avoiding the formation of stripes or holes. And through the aggregation of worst and average values ​​and the quantity penalty value, it balances the worst tooth surface quality with the overall number of usable tooth surfaces, improving the stability and feasibility of selecting the optimal pose.

[0067] In some embodiments of this application, S700, based on the cost function value, iteratively optimizes the candidate spatial pose parameter set within a preset parameter range to obtain the optimal sensor spatial pose parameter set, specifically including: Calculate the cost function value corresponding to the parameters of each candidate spatial pose parameter group, and select the candidate spatial pose parameter group with the smallest cost function value as the optimal sensor spatial pose parameter group.

[0068] In some embodiments of this application, iterative optimization may employ evolutionary strategies, grid search, or random search. During the optimization process, candidate spatial pose parameter sets are generated through traversal or iteration. The cost function value corresponding to each candidate spatial pose parameter set is calculated, and the candidate spatial pose parameter set with the smallest cost function value is retained as the optimal sensor spatial pose parameter set, and its corresponding optimal cost function value is recorded.

[0069] In some embodiments of this application, S800, based on the optimal sensor spatial pose parameter set, determines the spatial pose parameter range of the line laser sensor, wherein the cost function value corresponding to the spatial pose parameter range is less than or equal to the cost function value corresponding to the optimal sensor spatial pose parameter set plus a preset tolerance value, including: Specifically, by adding a preset tolerance value to the cost function value corresponding to the optimal sensor spatial pose parameter set as a retention condition, the parameters of the optimal sensor spatial pose parameter set are expanded into a range of values, which serves as the spatial pose parameter range. The cost function value of the spatial pose parameter range must be less than or equal to the retention condition. The spatial pose parameter range of the line laser sensor includes at least one value interval corresponding to a spatial pose parameter.

[0070] The specific process for determining the range of spatial pose parameters is as follows: The parameters in the optimal sensor spatial pose parameter set are divided into target parameters and constraint parameters. Target parameters can be at least two parameters that have the greatest impact on the measurement; for example, the target parameter could be the gear phase angle. With lateral translation parameters The constraint parameters can be other parameters, such as rotation parameters. Translation parameters Of course, in other embodiments of this application, the target parameter and constraint parameter may be other parameters, which will not be elaborated here.

[0071] A two-stage search is performed on the target parameter within a preset region to obtain the range of values ​​for the target parameter. The constraint parameter is searched within the neighborhood of the optimal sensor spatial pose parameter set to obtain a smaller range of values ​​for the constraint parameter.

[0072] The two-stage search includes a coarse scan search and a local fine scan search. The coarse scan search has a larger step size than the fine scan search. The coarse scan search traverses or samples within a preset region, i.e., within a preset target parameter search interval, with a larger step size to determine local candidate regions. The local fine scan search performs a dense search within the local candidate regions with a smaller step size to accurately determine the value range of the target parameters. Both the coarse scan search and the local fine scan search use the cost function value corresponding to the optimal sensor spatial pose parameter set plus a preset tolerance value as a retention condition. Based on the set of candidate spatial pose parameter sets that meet the retention condition, the minimum and maximum values ​​are taken in the corresponding parameter dimensions to form the value range of each target parameter.

[0073] Furthermore, for the constraint parameters, a search is conducted within the neighborhood of the optimal sensor spatial pose parameter set, and candidate solutions are selected based on the retention conditions. The candidate solution set takes the minimum and maximum values ​​in each constraint parameter dimension to form the value range of each constraint parameter.

[0074] Furthermore, the range of values ​​for the target parameters and the range of values ​​for the constraint parameters together constitute the spatial pose parameter range of the line laser sensor. The spatial pose parameter range can include the value ranges of seven spatial pose parameters, namely the rotation parameters of the line laser sensor. Translation parameters and gear phase angle The range of values ​​for . Figure 6 The tooth surface condition when the line laser sensor uses the optimal spatial pose parameters.

[0075] In this embodiment, at least two parameters are set as target parameters with a large value range, and the remaining parameters are set as constraint parameters with a small value range, which can balance operability and measurement stability.

[0076] In some embodiments of this application, in order to further improve the pose planning efficiency when changing gears of different specifications, the spatial pose optimization method of the line laser gear measurement sensor of this application may also include step S900, offline construction and online retrieval of the spatial pose parameter library, based on the above steps.

[0077] The offline database building phase includes: Construct a preset gear parameter set, which contains a combination of key geometric parameters for gears of various specifications. The key geometric parameters include at least the number of teeth, module, and pressure angle, and may further include helix angle, tooth width, displacement coefficient, and / or addendum coefficient.

[0078] Furthermore, for each set of key geometric parameters in the preset gear parameter set, steps S100 to S800 are executed to obtain the corresponding spatial pose parameter range.

[0079] Furthermore, using the key geometric parameters of the gear as index keys and the spatial pose parameter range as index values, the index keys and index values ​​are stored in a storage unit to construct a spatial pose parameter library. To facilitate retrieval, in some embodiments of this application, the index keys can be normalized, discretized, or range-defined, and a search structure or index table can be established for the index keys. The search structure refers to a data storage format that structurally organizes the discretized and range-defined gear parameter index keys, enabling rapid matching and efficient retrieval of gear parameters with the spatial pose parameter range of the line laser sensor.

[0080] The online search phase includes: The key geometric parameters of the gear under test are obtained, and the spatial pose parameter library is searched and matched based on the key geometric parameters to output the corresponding spatial pose parameter range.

[0081] The retrieval and matching methods include one of the following: exact matching, nearest neighbor matching, and interpolation matching. Exact matching is used when the key geometric parameters of the gear under test are consistent with the index keys in the parameter library. Nearest neighbor matching is used to select the pose parameter range corresponding to the index key closest to the key geometric parameters of the gear in the spatial pose parameter library according to a preset distance metric. Interpolation matching is used when the key geometric parameters of the gear under test are located between multiple index keys. It interpolates and fuses the pose parameter ranges corresponding to multiple index keys to obtain a spatial pose parameter range that matches the specifications of the gear under test and outputs it.

[0082] The embodiments of this application have been described in detail above with reference to the accompanying drawings. However, this application is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of this application.

Claims

1. A method for optimizing the spatial pose of a line laser gear measurement sensor, characterized in that, include: Obtain the key geometric parameters of the gear, establish a gear tooth surface geometric model based on the key geometric parameters, and generate tooth surface sampling points and corresponding tooth surface unit normal vectors in the gear coordinate system; Based on the candidate spatial pose parameter set of the line laser sensor, the tooth surface sampling points and tooth surface unit normal vector in the gear coordinate system are transformed to the line laser coordinate system. The candidate spatial pose parameter set includes at least rotation parameters, translation parameters and gear phase angle. Acquire the parameters of the line laser measurement system and establish an effective field-of-view model of the line laser sensor in the line laser coordinate system; Based on the effective field-of-view model, effective sampling points that meet the preset measurement feasibility conditions are selected from the tooth surface sampling points in the line laser coordinate system. Using the opposite direction of the laser beam direction corresponding to the effective sampling point as the measurement direction, calculate the angle between the measurement direction and the unit normal vector of the tooth surface of the effective sampling point in the linear laser coordinate system; Construct the spatial pose evaluation cost function of the line laser sensor, and calculate the cost function value of each candidate spatial pose parameter group; Based on the cost function value, the candidate spatial pose parameter set is iteratively optimized within a preset parameter range to obtain the optimal sensor spatial pose parameter set. Based on the optimal sensor spatial pose parameter set, the spatial pose parameter range of the line laser sensor is determined, wherein the cost function value corresponding to the spatial pose parameter range is less than or equal to the cost function value corresponding to the optimal sensor spatial pose parameter set plus a preset tolerance value.

2. The method for optimizing the spatial pose of a line laser gear measuring sensor according to claim 1, characterized in that, The generation of tooth surface sampling points in the gear coordinate system includes: The tooth profile curve is parameterized using the involute parameters of the gear, and the gear tooth surface is extended along the tooth width direction to obtain a parameterized representation of the tooth surface. A two-dimensional sampling grid is established in the involute parameter direction and the tooth width direction to sample the gear tooth surface, thereby obtaining the tooth surface sampling points in the gear coordinate system.

3. The spatial pose optimization method for a line laser gear measurement sensor according to claim 1, characterized in that, The candidate spatial pose parameter set Represented as: ， in, The rotational parameters of the line laser sensor relative to the gear coordinate system are... The translation parameter of the line laser sensor relative to the gear coordinate system. The gear phase angle; For the coordinates of the tooth surface sampling points in the gear coordinate system coordinates in the linear laser coordinate system Represented as: ， in, The rotation matrix is ​​constructed using the rotation parameters. The translation matrix is ​​constructed using the translation parameters; For the unit normal vector of the tooth surface in the gear coordinate system The vector in the line laser coordinate system Represented as: 。 4. The method for optimizing the spatial pose of a line laser gear measuring sensor according to claim 1, characterized in that, The step of establishing the effective field-of-view model of the line laser sensor in the line laser coordinate system includes: An original field-of-view model of the line laser sensor is established in the line laser coordinate system. The original field-of-view model represents the theoretical effective measurement area of ​​the line laser sensor. The original field-of-view model is subjected to lateral shrinking and vertical bottom raising to obtain the effective field-of-view model.

5. The method for optimizing the spatial pose of a line laser gear measuring sensor according to claim 1, characterized in that, The preset measurement feasibility conditions include visibility conditions, which include: Obtain the center point of the tip surface of each tooth of the gear, remove the teeth whose center point of the tip surface is located outside the effective field of view model, and then place them in the linear laser coordinate system. Next, remove the center point of the tooth tip surface. Coordinates less than the center point of the gear The coordinates of the gear teeth are used to obtain the target gear teeth; When the center point of the tooth tip surface of the target tooth is located in the linear laser coordinate system When the target tooth is in the negative side region of the shaft, the right tooth surface of the target tooth is selected as the target tooth surface; When the center point of the tooth tip surface of the target tooth is located in the linear laser coordinate system When the target tooth is in the positive side region of the shaft, the left tooth surface of the target tooth is selected as the target tooth surface; The tooth surface sampling points on the target tooth surface are selected to form the first sampling point set.

6. The method for optimizing the spatial pose of a line laser gear measuring sensor according to claim 5, characterized in that, The preset measurement feasibility conditions also include occlusion conditions, which include: The linear laser coordinate system is defined by the discrete arrangement of the multiple emitter units of the linear laser sensor. Axial direction; In the linear laser coordinate system, select the tooth surface sampling point on the target tooth surface. The position of the transmitter unit with the smallest distance in the axial direction is taken as the position of the transmitter unit corresponding to the tooth surface sampling point on the target tooth surface; Obstruction determination feature points are obtained on the target tooth surface. The obstruction determination feature points are the intersection points of the cylindrical surface of the tooth profile control circle and the tooth profile curve. The tooth apex of the adjacent tooth of the target tooth is obtained. The tooth apex is the intersection point of the tooth tip circle and the tooth profile curve, and is located on the side of the target tooth closer to the corresponding transmitter unit position. The obstruction determination feature points, the tooth apex, and the center point of the tooth tip surface are located on the same plane perpendicular to the axis of the gear. The occlusion determination feature point, the tooth vertex, and the emitter unit position are projected onto the linear laser coordinate system. In the plane, an incident beam vector of the laser beam is constructed based on the projection points of the transmitter unit position and the tooth apex. A comparison vector is constructed based on the projection points of the transmitter unit position and the occlusion determination feature points. The incident beam vector and the comparison vector are then compared. Two-dimensional cross product in a plane; Based on the positive or negative value of the two-dimensional cross product, it is determined that the occlusion determination feature point is located on the side of the corresponding laser beam. The feature point located on the side of the corresponding laser beam is then discarded if the target tooth is located in the linear laser coordinate system. Different target tooth surfaces on the sides of the shaft; If the occlusion determination feature point is located laterally to the corresponding laser beam and the target gear tooth is located in the linear laser coordinate system... If the lateral orientation of the shafts is the same, then determine whether the absolute value of the two-dimensional cross product is greater than a preset cross product tolerance threshold, and discard the target tooth surface whose absolute value of the two-dimensional cross product is less than or equal to the preset cross product tolerance threshold. Remove the tooth surface sampling points on the target tooth surface from the first sampling point set to obtain the second sampling point set.

7. The method for optimizing the spatial pose of a line laser gear measuring sensor according to claim 6, characterized in that, The preset measurement feasibility conditions also include field of view conditions, which include: Determine whether the tooth surface sampling points in the second sampling point set are within the field of view defined by the effective field of view model, and remove the tooth surface sampling points located outside the field of view defined by the effective field of view model to obtain a third sampling point set including the effective sampling points.

8. The method for optimizing the spatial pose of a line laser gear measurement sensor according to claim 7, characterized in that, The construction of the spatial pose evaluation cost function for the line laser sensor and the calculation of the cost function value for each candidate spatial pose parameter group include: The ratio of the number of valid sampling points in the third sampling point set to the number of tooth surface sampling points in the second sampling point set is used as the field of view coverage rate, and the complement number of the field of view coverage rate is used as the field of view coverage penalty value. The valid sampling points with an included angle greater than a preset angle threshold are taken as bad points, and the ratio of the number of bad points to the number of valid sampling points is calculated to obtain the ratio of angle non-compliance points. Calculate the ratio of the included angle corresponding to the bad point to the preset angle threshold to obtain the angle exceeding the threshold value; Multiple bad points are arranged in the direction of involute parameters and tooth width to form a bad point binary matrix. The bad point binary matrix is ​​convolved by a multi-scale convolution kernel to calculate several local bad point density response values. When at least one of the local bad point density response values ​​exceeds the corresponding response threshold, the maximum value among the ratios of the local bad point density response value to the corresponding response threshold is taken as the cluster penalty value. The single-tooth surface cost is obtained by summing the field coverage penalty value, the ratio of angle non-compliant points, the angle exceeding the threshold amplitude value, and the clustering penalty value according to the first preset weighting. The mass cost is obtained by summing the worst and average values ​​of all the single tooth surface cost values ​​according to the second preset weighting. The evaluation value is obtained by summing the ratio of the field coverage rate and the effective sampling points whose included angle is less than or equal to the preset angle threshold according to the third preset weighting. When the evaluation value is less than the preset reference value, a quantity penalty value is introduced. The cost function value is obtained by summing the quality cost value and the quantity penalty value according to the fourth preset weighting.

9. The method for optimizing the spatial pose of a line laser gear measuring sensor according to claim 1, characterized in that, The step of iteratively optimizing the candidate spatial pose parameter set within a preset parameter range based on the cost function value to obtain the optimal sensor spatial pose parameter set includes: Calculate the cost function value corresponding to the parameters of each candidate spatial pose parameter group, and select the candidate spatial pose parameter group with the smallest cost function value as the optimal sensor spatial pose parameter group.

10. The method for optimizing the spatial pose of a line laser gear measurement sensor according to claim 1, characterized in that, Determining the range of spatial pose parameters of the line laser sensor based on the optimal sensor spatial pose parameter set includes: The parameters in the optimal sensor spatial pose parameter set are divided into target parameters and constraint parameters; The range of values ​​for the target parameter is obtained by a two-stage search, which includes a coarse scan search and a fine scan search. The search step size of the coarse scan search is larger than that of the fine scan search. The coarse scan search determines a local candidate region within a preset area, and the fine scan search determines the range of values ​​for the target parameter within the local candidate region. The range of values ​​for the constraint parameters is obtained by searching within the neighborhood of the optimal sensor spatial pose parameter set. The spatial pose parameter range is obtained based on the value range of the target parameter and the value range of the constraint parameter.

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