Spectral confocal probe pose calibration method and device based on plane constraint

Abstract

The application provides a plane constraint-based spectral confocal probe pose calibration method and device, and belongs to the field of precision measurement and instrument technology.The method comprises the following steps: firstly, at least three non-coplanar plane standard parts are measured by using a contact probe, and through coordinate conversion and fitting, equations of the standard planes in a machine coordinate system are accurately established; then, the same plane parts are measured by using a spectral confocal probe, and the obtained measurement point coordinates and distance values are combined with the known plane equations to construct a linear over-determined equation set about the probe pose parameters (including an optical axis direction vector and a space position vector); finally, the equation set is solved by using a least square method to obtain accurate pose parameters.The application converts a nonlinear problem into a linear solution, avoids iterative calculation, and significantly improves the calibration efficiency and accuracy.Meanwhile, the use of plane constraint allows the measurement points to be uniformly distributed, effectively reduces the equation set ill-conditioning, and enhances the robustness of the calibration process.

Description

Technical Field

[0001] This invention relates to the field of precision measurement and instrumentation technology, and in particular to a method and apparatus for calibrating the pose of a spectral confocal probe based on planar constraints. Background Technology

[0002] A confocal spectral probe is a high-precision non-contact measurement sensor based on the principles of optical dispersion and confocal technology. In industrial applications, it is typically clamped onto a coordinate measuring machine (CMM), which then moves the probe for measurement. The pose calibration error of the confocal spectral probe directly affects measurement accuracy; therefore, its pose needs to be calibrated to ensure accurate measurements. Most methods for calibrating confocal spectral probes employ a standard sphere-based approach. This involves measuring the standard sphere from multiple angles, fitting its center, and solving for the sensor's mounting pose parameters. However, this method suffers from limitations. Because the angles and measurement points measured by the standard sphere are relatively small, the coupling between spatial position and beam direction during equation-solving leads to reduced calibration accuracy.

[0003] A composite probe is created by combining a spectral confocal probe with a contact probe. This allows for the construction of a multi-degree-of-freedom scanning device based on a coordinate measuring machine (CMM) for measuring the surface dimensions and morphology of aircraft blades. Figure 1 As shown, Figure 1 This is a schematic diagram of the aircraft blade measurement system provided by the present invention. Based on a contact coordinate measuring machine (CMM), this device integrates a turntable and a spectral confocal sensor to construct a spectral confocal blade measurement system. The turntable is mounted on the marble platform of the CMM, forming a four-axis linkage measurement and scanning system. The spectral confocal probe and the contact probe are combined into a composite probe, establishing a defined spatial positional relationship between the two.

[0004] Ideally, the spectral confocal probe and the contact scanning probe of the coordinate measuring machine (CMM) form a contact-non-contact composite scanning probe. The optical probe beam direction is aligned with the Y-axis of the machine tool, and the spectral confocal probe and the trigger-type probe mounted on the CMM have a fixed relative position. However, due to the inaccurate positioning reference of the spectral confocal probe during installation, eccentricity and tilt will inevitably occur. These installation errors will reduce measurement accuracy, and the unknown zero point position will make it impossible to solve the absolute coordinates of the workpiece in space. Therefore, it is necessary to calibrate the pose of the spectral confocal probe. Summary of the Invention

[0005] The measurement system requires the orientation calibration of the spectral confocal probe. Considering that this system uses a composite probe, this invention proposes a spectral confocal probe orientation calibration method and device based on planar constraints, which simplifies the calibration operation and improves the accuracy and robustness of the spectral confocal probe orientation calibration.

[0006] In a first aspect, the present invention provides a method for calibrating the pose of a spectral confocal probe based on planar constraints, comprising: establishing a coordinate system including a three-coordinate machine coordinate system, a contact probe coordinate system, a spectral confocal probe coordinate system, and a standard planar coordinate system; determining the pose parameters of the spectral confocal probe that need to be calibrated for the transformation between the spectral confocal probe coordinate system and the three-coordinate machine coordinate system, wherein the pose parameters include an optical axis direction vector and a spatial position vector; the optical axis direction vector is a vector formed by the direction cosines of the angles between the optical axis and the three coordinate axes of the spectral confocal probe coordinate system, and the spatial position vector is the offset direction of the origin of the spectral confocal probe coordinate system relative to the origin of the machine coordinate system. The process involves: measuring at least three non-coplanar planar standard parts using the contact probe; measuring multiple non-collinear points on each planar standard part; transforming the coordinates of the measurement points from the contact probe coordinate system to the coordinate system of a three-coordinate machine; fitting the plane equations corresponding to each planar standard part in the coordinate system of the three-coordinate machine; measuring the at least three non-coplanar planar standard parts using a spectral confocal probe; recording the coordinate values ​​displayed on the three-coordinate machine and the distance values ​​measured by the spectral confocal probe for each measurement point; combining the coordinate values, distance values, and the corresponding plane equations to construct a system of linear equations about the pose parameters; and solving the system of linear equations to obtain the pose parameters.

[0007] According to the planar constraint-based spectral confocal probe pose calibration method provided by the present invention, a coordinate system system is established including a three-coordinate machine coordinate system, a contact probe coordinate system, a spectral confocal probe coordinate system, and a standard planar coordinate system. This includes: setting the origin of the three-coordinate machine coordinate system as the machine zero point, with the coordinate axes parallel to the direction of movement of the machine guide rail; setting the origin of the contact probe coordinate system at the center of the probe tip, with the coordinate axes parallel to the coordinate axes of the machine coordinate system; and setting the origin of the spectral confocal probe coordinate system as the starting point of the spectral confocal probe's measurement range, with the coordinate axes parallel to the coordinate axes of the machine coordinate system.

[0008] According to the planar constraint-based spectral confocal probe pose calibration method provided by the present invention, the step of fitting the planar equation specifically includes: for each planar standard, selecting no less than three non-collinear measurement points; substituting the coordinates of each measurement point in the three-coordinate machine coordinate system into the planar equation; constructing an overdetermined linear equation system and solving it to determine the planar equation parameters corresponding to the planar standard.

[0009] According to the planar constraint-based spectral confocal probe pose calibration method provided by the present invention, the step of constructing a linear equation system specifically includes:

[0010] Define the pose parameters to be calibrated, where the optical axis direction vector is... The spatial position vector is , Let X, Y, and Z be the components of the optical axis direction vector in the coordinate system of the spectral confocal probe, respectively. These are the components of the spatial position vector along the X, Y, and Z axes in the three-coordinate machine coordinate system;

[0011] For the k The first standard plane i Each measurement point, based on the coordinates displayed by the coordinate measuring machine. Distance values ​​measured by a spectral confocal probe And the plane equation parameters corresponding to the planar standard parts. , , as well as Establish the equation:

[0012] .

[0013] The planar constraint-based spectral confocal probe pose calibration method provided by the present invention solves a system of linear equations to obtain pose parameters, including:

[0014] Let the vector of parameters to be determined be The equations corresponding to each measurement point are rearranged into linear form. ;

[0015] in, , ;

[0016] Stack the p and q points of all measurements to form a matrix P and a vector Q, respectively, and then use the formula... Solve for the pose parameters.

[0017] According to the planar constraint-based spectral confocal probe pose calibration method provided by the present invention, the measurement points are uniformly distributed on the entire plane.

[0018] According to the planar constraint-based spectral confocal probe pose calibration method provided by the present invention, the spectral confocal probe and the contact probe are integrated into a composite probe and mounted on a coordinate measuring machine with a turntable.

[0019] The planar constraint-based spectral confocal probe pose calibration method provided by the present invention further includes: determining the transformation information for converting the measurement points of the spectral confocal probe to the coordinate system of a three-coordinate machine; and realizing the coordinate transformation of the measurement points according to the solved pose parameters and transformation relationship.

[0020] Secondly, the present invention also provides a spectral confocal probe pose calibration device based on planar constraints, comprising:

[0021] The first processing module is used to establish a coordinate system that includes a three-coordinate machine coordinate system, a contact probe coordinate system, a spectral confocal probe coordinate system, and a standard plane coordinate system.

[0022] The second processing module is used to determine the pose parameters of the spectral confocal probe that need to be calibrated for the transformation between the spectral confocal probe coordinate system and the three-coordinate machine coordinate system. The pose parameters include the optical axis direction vector and the spatial position vector. The optical axis direction vector is the vector formed by the direction cosine of the angle between the optical axis and the three coordinate axes of the spectral confocal probe coordinate system. The spatial position vector is the offset vector of the origin of the spectral confocal probe coordinate system relative to the origin of the machine coordinate system.

[0023] The third processing module is used to measure at least three non-coplanar planar standard parts using the contact probe, measure multiple non-collinear points on each planar standard part, transform the coordinates of the measurement points from the contact probe coordinate system to the three-coordinate machine coordinate system, and fit the plane equations corresponding to each planar standard part in the three-coordinate machine coordinate system.

[0024] The fourth processing module is used to measure the at least three non-coplanar planar standard parts using a spectral confocal probe, record the coordinate values ​​displayed by the coordinate measuring machine and the distance values ​​measured by the spectral confocal probe for each measurement point, combine the coordinate values ​​and distance values ​​with the corresponding planar equations to construct a system of linear equations about the pose parameters, and solve the system of linear equations to obtain the pose parameters.

[0025] The method and apparatus for spectral confocal probe pose calibration based on planar constraints provided by this invention have the following advantages compared with the prior art:

[0026] (1) The calibration operation is simple and the accuracy is high. This invention uses a contact probe to pre-calibrate at least three non-coplanar planar standard parts, which provides an accurate and known spatial constraint reference for the subsequent pose calibration of the spectral confocal probe. The calibration process is transformed into solving a system of linear overdetermined equations, avoiding the complexity and accuracy loss caused by nonlinear iterative solutions in traditional methods, thereby improving the computational efficiency and final accuracy of the calibration parameters.

[0027] (2) The calibration process is robust. Compared with the ill-conditioned problems of the equations caused by the concentration of measurement points in the limited angle and range of the standard sphere in traditional methods, the method of this invention allows and encourages the uniform distribution of measurement points on the planar standard. This approach effectively reduces the linear correlation between the row vectors in the constructed equation system, enhances the numerical stability, and makes the calibration results insensitive to measurement noise and point selection, thus significantly improving the overall robustness.

[0028] (3) Particularly suitable for composite precision measurement systems. The method of this invention is naturally adapted to composite probe systems that integrate spectral confocal probes and contact probes (such as four-axis linkage scanning systems used for measuring the profiles of aerospace blades). This method makes full use of the existing contact probes in the system to complete the establishment of a high-precision reference plane, realizes the complementary advantages of the two probes and the unification of the calibration process, and provides reliable calibration technology support for the precision and efficient measurement of complex curved surface parts. Attached Figure Description

[0029] To more clearly illustrate the technical solutions in this invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0030] Figure 1 This is a schematic diagram of the structure of the aircraft blade measurement system provided by the present invention;

[0031] Figure 2 This is a flowchart illustrating the spectral confocal probe pose calibration method based on planar constraints provided by the present invention.

[0032] Figure 3 This is a schematic diagram of the coordinate system provided by the present invention;

[0033] Figure 4 This is a schematic diagram of the structure of the spectral confocal probe pose calibration model provided by the present invention;

[0034] Figure 5 This is a schematic diagram of the spectral confocal probe calibration provided by the present invention;

[0035] Figure 6 This is a schematic diagram of the structure of the electronic device provided by the present invention. Detailed Implementation

[0036] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0037] It should be noted that, in the description of the embodiments of the present invention, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0038] The terms "first," "second," etc., used in this application are used to distinguish similar objects and not to describe a specific order or sequence. It should be understood that such terms can be used interchangeably where appropriate so that embodiments of this application can be implemented in orders other than those illustrated or described herein, and the objects distinguished by "first," "second," etc., are generally of the same class, without limiting the number of objects; for example, a first object can be one or more. Furthermore, "and / or" indicates at least one of the connected objects, and the character " / " generally indicates that the preceding and following objects are in an "or" relationship.

[0039] Figure 2 This is a flowchart illustrating the planar constraint-based spectral confocal probe pose calibration method provided by the present invention, as shown below. Figure 2 As shown, including but not limited to the following steps:

[0040] Step 201: Establish a coordinate system that includes a three-coordinate machine coordinate system, a contact probe coordinate system, a spectral confocal probe coordinate system, and a standard plane coordinate system;

[0041] The coordinate systems include a coordinate system for a three-coordinate machine, a coordinate system for a contact probe, a coordinate system for a spectral confocal probe, and a standard plane (for calibration). The positional relationships of the measurement system coordinate systems are as follows: Figure 3 As shown, Figure 3 This is a schematic diagram of the coordinate system provided by the present invention: Machine Coordinate System The origin is the zero point of the coordinate measuring machine, and the X, Y, and Z axes are parallel to the direction of movement of the machine guide rail; the contact probe coordinate system... Origin of coordinates Located at the center of the ruby ​​sphere at the tip of the probe, with the X, Y, and Z axes parallel to the machine coordinate system's three coordinate axes; non-contact probe coordinate system. Origin of coordinates The X, Y, and Z axes are parallel to the machine coordinate system and the standard plane coordinate system, serving as the starting point of the spectral confocal probe's measurement range. .

[0042] Step 202: Determine the pose parameters of the spectral confocal probe to be calibrated. The pose parameters include the optical axis direction vector and the spatial position vector. The optical axis direction vector is the vector formed by the direction cosines of the angles between the optical axis and the three coordinate axes of the spectral confocal probe coordinate system. The spatial position vector is the offset vector of the origin of the spectral confocal probe coordinate system relative to the origin of the machine coordinate system.

[0043] Figure 4 This is a schematic diagram of the spectral confocal probe pose calibration model provided by the present invention. The specific parameters to be calibrated are as follows: Figure 4 As shown, including the beam direction: Spatial location Ideally, the spectral confocal probe is fixedly connected to the Z-axis, with its optical axis parallel to the Y-axis. The origin of the spectral confocal probe is located a certain distance from the origin of the contact probe. Because the confocal spectral probe cannot be perfectly aligned with the Y-axis during installation, a spatial tilt angle will occur. Let the angles between the optical axis of the confocal spectral probe and the three coordinate axes be... ， Then the unit direction vector of the optical axis in the coordinate system of the spectral confocal probe is: .

[0044] Assuming the coordinate information displayed by the coordinate machine is Given a spectral confocal probe measuring at a distance of d, and considering probe tilt, the coordinates of the measurement point obtained by the spectral confocal probe in the coordinate system of the three-coordinate machine are:

[0045] .

[0046] Based on the above conversion information (conversion formula), after solving for the pose parameters, the coordinates of the measurement point of the spectral confocal probe in the coordinate system of the three-coordinate machine can be obtained.

[0047] Step 203: Use the contact probe to measure at least three non-coplanar planar standard parts, measure multiple non-collinear points on each planar standard part, transform the coordinates of the measurement points from the contact probe coordinate system to the three-coordinate machine coordinate system, and fit the plane equations corresponding to each planar standard part in the three-coordinate machine coordinate system.

[0048] Suppose for the th One flat standard part ( ), select on its surface ( Measurements are taken at the ) non-collinear points. In the coordinate system of the three-coordinate machine, the )th On the plane, the first The coordinates of the points in the contact probe coordinate system are: .

[0049] Let the equation of the plane be:

[0050]

[0051] in: It is a coefficient of the plane.

[0052] Substituting each measurement point into the equation, we obtain a system of linear equations:

[0053]

[0054] Rewrite the system of equations in matrix form:

[0055]

[0056] Where: coefficient matrix for matrix:

[0057]

[0058] parameter vector

[0059] constant vector

[0060] This is an overdetermined system of linear equations. Solving this equation yields the parameters of the standard plane.

[0061] Step 204: Use a spectral confocal probe to measure the at least three non-coplanar planar standard parts, record the coordinate values ​​displayed by the coordinate measuring machine and the distance values ​​measured by the spectral confocal probe for each measurement point, combine the coordinate values ​​and distance values ​​with the corresponding planar equations to construct a system of linear equations about the pose parameters, and solve the system of linear equations to obtain the pose parameters.

[0062] A spectral confocal probe is used to measure n (n≥3) groups of non-coplanar planar standard parts. Twenty points are selected on each planar standard part for measurement. The point position information obtained in the coordinate system of the spectral confocal probe is converted into the coordinate information in the coordinate system of the base three-coordinate machine. Then, the coordinate points are substituted into the plane equations, and the established equation system is solved to obtain the pose parameters of the spectral confocal probe.

[0063] To reduce calibration errors and improve algorithm robustness, n (n≥3) non-coplanar planar standard parts are used to calibrate the spatial pose of the spectral confocal probe, such as... Figure 5 As shown, Figure 5 This is a schematic diagram of the spectral confocal probe calibration provided by the present invention. The plane equations corresponding to each plane are known (obtained from step 203):

[0064]

[0065] Suppose for the th One flat standard part ( ), select on its surface ( ) non-collinear points are measured. For the ) points... The first plane Measurement points ( Record the following data: coordinates of the points displayed by the coordinate measuring machine: Distance values ​​measured by the spectral confocal probe: The coordinates of the measurement point obtained by the spectral confocal probe in the machine coordinate system are: .

[0066] Due to the measurement point It should be located in the first Therefore, it lies on a plane and satisfies the plane equation. Substituting the coordinates, we get:

[0067]

[0068] in, k The serial number of the standard plane. ; and These are the parameters of the standard plane.

[0069] Rearranging the above equation, we get:

[0070]

[0071] Let the vector of parameters to be determined be: For the first On the plane, the first A number of measurement points can be written in linear form:

[0072]

[0073] in, , .

[0074] By combining the equations corresponding to all measurement points and constructing a normal matrix, we obtain the least-squares solution for the spatial pose of the spectral confocal probe:

[0075]

[0076] in:

[0077]

[0078]

[0079] The aforementioned matrix equations are linear overdetermined equations, which can be directly calculated quickly using normal matrices without iterative processes. When using a plane for calibration, the measurement points can be evenly distributed across the entire plane, reducing the linear correlation between the equations, improving the robustness of the calculation process, reducing fitting errors, and enhancing calibration accuracy.

[0080] Secondly, the present invention also provides a spectral confocal probe pose calibration device based on planar constraints, comprising:

[0081] The first processing module is used to establish a coordinate system that includes a three-coordinate machine coordinate system, a contact probe coordinate system, a spectral confocal probe coordinate system, and a standard plane coordinate system.

[0082] The second processing module is used to determine the pose parameters of the spectral confocal probe that need to be calibrated for the transformation between the spectral confocal probe coordinate system and the three-coordinate machine coordinate system. The pose parameters include the optical axis direction vector and the spatial position vector. The optical axis direction vector is the vector formed by the direction cosine of the angle between the optical axis and the three coordinate axes of the spectral confocal probe coordinate system. The spatial position vector is the offset vector of the origin of the spectral confocal probe coordinate system relative to the origin of the machine coordinate system.

[0083] The third processing module is used to measure at least three non-coplanar planar standard parts using the contact probe, measure multiple non-collinear points on each planar standard part, transform the coordinates of the measurement points from the contact probe coordinate system to the three-coordinate machine coordinate system, and fit the plane equations corresponding to each planar standard part in the three-coordinate machine coordinate system.

[0084] The fourth processing module is used to measure the at least three non-coplanar planar standard parts using a spectral confocal probe, record the coordinate values ​​displayed by the coordinate measuring machine and the distance values ​​measured by the spectral confocal probe for each measurement point, combine the coordinate values ​​and distance values ​​with the corresponding planar equations to construct a system of linear equations about the pose parameters, and solve the system of linear equations to obtain the pose parameters.

[0085] It should be noted that the planar constraint-based spectral confocal probe pose calibration device provided in this embodiment of the invention can execute the planar constraint-based spectral confocal probe pose calibration method described in any of the above embodiments during specific operation, which will not be elaborated in this embodiment.

[0086] In summary, the planar constraint-based spectral confocal probe pose calibration method and apparatus provided by this invention have the following advantages compared with the prior art:

[0087] (1) The calibration operation is simple and the accuracy is high. This invention uses a contact probe to pre-calibrate at least three non-coplanar planar standard parts, which provides an accurate and known spatial constraint reference for the subsequent pose calibration of the spectral confocal probe. The calibration process is transformed into solving a system of linear overdetermined equations, avoiding the complexity and accuracy loss caused by nonlinear iterative solutions in traditional methods, thereby improving the computational efficiency and final accuracy of the calibration parameters.

[0088] (2) The calibration process is robust. Compared with the ill-conditioned problems of the equations caused by the concentration of measurement points in the limited angle and range of the standard sphere in traditional methods, the method of this invention allows and encourages the uniform distribution of measurement points on the planar standard. This approach effectively reduces the linear correlation between the row vectors in the constructed equation system, enhances the numerical stability, and makes the calibration results insensitive to measurement noise and point selection, thus significantly improving the overall robustness.

[0089] (3) Particularly suitable for composite precision measurement systems. The method of this invention is naturally adapted to composite probe systems that integrate spectral confocal probes and contact probes (such as four-axis linkage scanning systems used for measuring the profiles of aerospace blades). This method makes full use of the existing contact probes in the system to complete the establishment of a high-precision reference plane, realizes the complementary advantages of the two probes and the unification of the calibration process, and provides reliable calibration technology support for the precision and efficient measurement of complex curved surface parts.

[0090] Figure 6 This is a schematic diagram of the structure of the electronic device provided by the present invention, such as... Figure 6 As shown, the electronic device may include a processor 610, a communications interface 620, a memory 630, and a communication bus 640. The processor 610, communications interface 620, and memory 630 communicate with each other via the communication bus 640. The processor 610 can call logic instructions from the memory 630 to execute a planar constraint-based spectral confocal probe pose calibration method.

[0091] Through the above description of the embodiments, those skilled in the art can clearly understand that each embodiment can be implemented by means of software plus necessary general-purpose hardware platforms, and of course, it can also be implemented by hardware. Based on this understanding, the above technical solutions, in essence or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, magnetic disk, optical disk, etc., and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute the methods described in the various embodiments or some parts of the embodiments.

[0092] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications 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.

Claims

1. A method for calibrating the pose of a spectral confocal probe based on planar constraints, characterized in that, include: Establish a coordinate system that includes a three-coordinate machine coordinate system, a contact probe coordinate system, a spectral confocal probe coordinate system, and a standard plane coordinate system; The pose parameters of the spectral confocal probe that need to be calibrated for the transformation between the spectral confocal probe coordinate system and the three-coordinate machine coordinate system are determined. The pose parameters include the optical axis direction vector and the spatial position vector. The optical axis direction vector is the vector formed by the direction cosine of the angle between the optical axis and the three coordinate axes of the spectral confocal probe coordinate system. The spatial position vector is the offset vector of the origin of the spectral confocal probe coordinate system relative to the origin of the machine coordinate system. The contact probe is used to measure at least three non-coplanar planar standard parts. Multiple non-collinear points on each planar standard part are measured. The coordinates of the measurement points are transformed from the contact probe coordinate system to the three-coordinate machine coordinate system, and the corresponding plane equations in the three-coordinate machine coordinate system are fitted. The at least three non-coplanar planar standard parts are measured using a spectral confocal probe. The coordinate values ​​displayed by the coordinate measuring machine and the distance values ​​measured by the spectral confocal probe are recorded for each measurement point. The coordinate values, distance values ​​and the corresponding planar equations are combined to construct a system of linear equations about the pose parameters. The system of linear equations is then solved to obtain the pose parameters.

2. The method for spectral confocal probe pose calibration based on planar constraints according to claim 1, characterized in that, Establish a coordinate system comprising a three-coordinate machine coordinate system, a contact probe coordinate system, a spectral confocal probe coordinate system, and a standard plane coordinate system, including: Set the origin of the coordinate system of the three-coordinate machine as the zero point of the three-coordinate measuring machine, and make the coordinate axes parallel to the direction of movement of the machine guide rail; The origin of the contact probe coordinate system is set at the center of the probe tip, and the coordinate axes are parallel to the coordinate axes of the machine coordinate system. Set the origin of the spectral confocal probe coordinate system as the starting point of the spectral confocal probe range, and make the coordinate axes parallel to the coordinate axes of the machine coordinate system.

3. The method for spectral confocal probe pose calibration based on planar constraints according to claim 1, characterized in that, The steps for fitting the plane equation specifically include: For each planar standard component, select no fewer than three non-collinear measurement points; Substitute the coordinates of each measurement point in the coordinate system of the three-coordinate machine into the plane equation; Construct and solve an overdetermined system of linear equations to determine the plane equation parameters corresponding to the plane standard part.

4. The method for spectral confocal probe pose calibration based on planar constraints according to claim 1, characterized in that, The steps for constructing the linear equation system specifically include: Define the pose parameters to be calibrated, where the optical axis direction vector is... The spatial position vector is , Let X, Y, and Z be the components of the optical axis direction vector in the coordinate system of the spectral confocal probe, respectively. These are the components of the spatial position vector along the X, Y, and Z axes in the three-coordinate machine coordinate system; For the k The first standard plane i Each measurement point, based on the coordinates displayed by the coordinate measuring machine. Distance values ​​measured by a spectral confocal probe And the plane equation parameters corresponding to the planar standard parts. , , as well as Establish the equation: 。 5. The method for spectral confocal probe pose calibration based on planar constraints according to claim 4, characterized in that, Solving the system of linear equations to obtain pose parameters includes: Let the vector of parameters to be determined be The equations corresponding to each measurement point are rearranged into linear form. ; in, , ; Stack the p and q points of all measurements to form a matrix P and a vector Q, respectively, and then use the formula... Solve for the pose parameters.

6. The method for spectral confocal probe pose calibration based on planar constraints according to claim 1, characterized in that, The measurement points are evenly distributed across the entire plane.

7. The method for spectral confocal probe pose calibration based on planar constraints according to claim 1, characterized in that, The spectral confocal probe and the contact probe are integrated into a composite probe and mounted on a coordinate measuring machine with a turntable.

8. The method for spectral confocal probe pose calibration based on planar constraints according to claim 1, characterized in that, Also includes: Determine the transformation information for converting the measurement points of the spectral confocal probe to the coordinate system of the three-coordinate machine; The coordinate transformation of the measurement point is achieved based on the solved pose parameters and transformation relationships.

9. A spectral confocal probe pose calibration device based on planar constraints, characterized in that, include: The first processing module is used to establish a coordinate system that includes a three-coordinate machine coordinate system, a contact probe coordinate system, a spectral confocal probe coordinate system, and a standard plane coordinate system. The second processing module is used to determine the pose parameters of the spectral confocal probe that need to be calibrated for the transformation between the spectral confocal probe coordinate system and the three-coordinate machine coordinate system. The pose parameters include the optical axis direction vector and the spatial position vector. The optical axis direction vector is the vector formed by the direction cosine of the angle between the optical axis and the three coordinate axes of the spectral confocal probe coordinate system. The spatial position vector is the offset vector of the origin of the spectral confocal probe coordinate system relative to the origin of the machine coordinate system. The third processing module is used to measure at least three non-coplanar planar standard parts using the contact probe, measure multiple non-collinear points on each planar standard part, transform the coordinates of the measurement points from the contact probe coordinate system to the three-coordinate machine coordinate system, and fit the plane equations corresponding to each planar standard part in the three-coordinate machine coordinate system. The fourth processing module is used to measure the at least three non-coplanar planar standard parts using a spectral confocal probe, record the coordinate values ​​displayed by the coordinate measuring machine and the distance values ​​measured by the spectral confocal probe for each measurement point, combine the coordinate values ​​and distance values ​​with the corresponding planar equations to construct a system of linear equations about the pose parameters, and solve the system of linear equations to obtain the pose parameters.

10. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the computer program, it implements the steps of the planar constraint-based spectral confocal probe pose calibration method as described in any one of claims 1 to 8.

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