A method, device, equipment and storage medium for posture decoupling kinematic calibration

Abstract

The present application discloses a posture decoupling kinematic calibration method, device, equipment and storage medium, the method includes: constructing a posture decoupling motion model based on equivalent rotation vectors and rigid body motion transformation rules; introducing posture errors, performing posture space decomposition through the posture decoupling motion model, and obtaining posture error expressions and position equivalent expressions; analyzing the coupling effect of posture changes on positions based on the posture error expressions and position equivalent expressions, and obtaining posture coupling increments; constructing a target decoupling calibration model based on the posture coupling increments and the initial decoupling calibration model; using the least squares method to solve the geometric errors of different degrees of freedom for the target decoupling calibration model based on the preset axis posture errors, and obtaining calibration errors. The present application can solve the technical problems that the prior art does not consider the influence of posture on position in a multi-degree-of-freedom motion system, and it is difficult to eliminate the error differences between different degrees of freedom, resulting in poor calibration and compensation effects.

Description

Technical Field

[0001] The present application relates to the field of mechanical motion technology, and in particular to a posture decoupling kinematic calibration method, device, equipment and storage medium. Background Art

[0002] Parts processing needs to have the characteristics of complex morphology, large size and high precision at the same time, so it is necessary to improve the processing stroke and operating accuracy of multi-axis manufacturing equipment to meet various complex needs. Five-axis is widely used in complex surface processing due to its posture adjustment capability, and its absolute positioning accuracy is the most critical performance indicator. Kinematic geometric error calibration is one of the effective ways to improve the absolute positioning accuracy of multi-degree-of-freedom motion systems. In processing situations where both position and posture need to maintain high precision, the existing technology mainly uses the method of minimizing the overall position and posture error to achieve calibration. However, due to differences in the dimensions, values ​​and measurement accuracy of position and posture, it will lead to differences in geometric errors between different degrees of freedom, and some posture errors will have weak convergence problems, making it difficult for the overall calibration method to achieve the optimal compensation effect of position and posture.

[0003] Although the current calibration method separates the parameters of the attitude and position matrices in the terminal homogeneous transformation matrix, it does not evaluate the influence of attitude on position, and the position matrix still has the coupling of position parameters and attitude parameters. Since this type of method cannot consider the influence of attitude on position, it is still difficult to achieve optimal calibration and optimal compensation of corresponding errors for each degree of freedom of the mechanism. Summary of the invention

[0004] The present application provides a posture decoupled kinematic calibration method, device, equipment and storage medium, which are used to solve the technical problem that the prior art does not consider the influence of posture on position in a multi-degree-of-freedom motion system, and it is difficult to eliminate the error difference between different degrees of freedom, resulting in poor calibration and compensation effects.

[0005] In view of this, the first aspect of the present application provides a posture decoupling kinematic calibration method, comprising:

[0006] Construct a posture decoupled motion model based on equivalent rotation vector and rigid body motion transformation rules;

[0007] Introducing a posture error, performing posture space decomposition through the posture decoupling motion model, and obtaining a posture error expression and a position equivalent expression;

[0008] Analyze the coupling effect of the posture change on the position according to the posture error expression and the position equivalent expression to obtain the posture coupling increment;

[0009] Constructing a target decoupling calibration model according to the posture coupling increment and the initial decoupling calibration model, wherein the initial decoupling calibration model is constructed according to the posture decoupling motion model;

[0010] The least square method is used to solve the geometric errors of different degrees of freedom of the target decoupling calibration model according to the preset axis posture error to obtain the calibration error.

[0011] Preferably, the posture error is introduced, and the posture space is decomposed by the posture decoupling motion model to obtain the posture error expression and the position equivalent expression, including:

[0012] Introducing a posture error into the posture decoupling motion model to construct an error decoupling motion model;

[0013] The attitude error is quantified by the error decoupling motion model to obtain an attitude error expression;

[0014] An equivalent rotation vector operation is performed on the error decoupling motion model to obtain an equivalent position expression.

[0015] Preferably, the least square method is used to solve the geometric errors of different degrees of freedom of the target decoupling calibration model according to the preset axis posture error to obtain the calibration error, including:

[0016] The preset axis posture error includes a preset axis attitude error and a preset axis position error;

[0017] Using the least square method to solve the attitude geometric error parameters according to the preset axis attitude error and the target decoupling calibration model;

[0018] Evaluate the coupling effect of the attitude change on the position according to the attitude geometric error parameter to obtain a coupling increment parameter;

[0019] The least square method is adopted to solve the position geometry error parameter according to the coupling increment parameter and the target decoupling calibration model to obtain the calibration error, wherein the calibration error includes the attitude geometry error parameter and the position geometry error parameter.

[0020] Preferably, the method of using the least square method to solve geometric errors of different degrees of freedom of the target decoupling calibration model according to the preset axis posture error to obtain the calibration error also includes:

[0021] After constructing the measurement coordinate system, obtain the rotation center and rotation radius of the B and C axes, and calculate the initial equivalent rotation vector;

[0022] Solve the rotation amounts of the B and C axes according to the collected target end position information and the initial equivalent rotation vector to obtain the attitude information;

[0023] Based on the posture information and the collected terminal X, Y, Z axis position information, the errors of the B, C, X, Y, and Z axes are calculated respectively to obtain the preset axis posture error and the preset axis position error.

[0024] The second aspect of the present application provides a posture decoupling kinematic calibration device, comprising:

[0025] A model building unit, used for building a posture decoupled motion model based on an equivalent rotation vector and rigid body motion transformation rules;

[0026] A posture decomposition unit is used to introduce a posture error, perform posture space decomposition through the posture decoupling motion model, and obtain a posture error expression and a position equivalent expression;

[0027] A coupling analysis unit, used for analyzing the coupling effect of the posture change on the position according to the posture error expression and the position equivalent expression, and obtaining a posture coupling increment;

[0028] A model adjustment unit, configured to construct a target decoupling calibration model according to the posture coupling increment and an initial decoupling calibration model, wherein the initial decoupling calibration model is constructed according to the posture decoupling motion model;

[0029] The calibration solving unit is used to solve the geometric errors of different degrees of freedom of the target decoupling calibration model according to the preset axis posture error by using the least square method to obtain the calibration error.

[0030] Preferably, the posture decomposition unit is specifically used for:

[0031] Introducing a posture error into the posture decoupling motion model to construct an error decoupling motion model;

[0032] The attitude error is quantified by the error decoupling motion model to obtain an attitude error expression;

[0033] An equivalent rotation vector operation is performed on the error decoupling motion model to obtain an equivalent position expression.

[0034] Preferably, the calibration solution unit is specifically used for:

[0035] The preset axis posture error includes a preset axis attitude error and a preset axis position error;

[0036] Using the least square method to solve the attitude geometric error parameters according to the preset axis attitude error and the target decoupling calibration model;

[0037] Evaluate the coupling effect of the attitude change on the position according to the attitude geometric error parameter to obtain a coupling increment parameter;

[0038] The least square method is adopted to solve the position geometry error parameter according to the coupling increment parameter and the target decoupling calibration model to obtain the calibration error, wherein the calibration error includes the attitude geometry error parameter and the position geometry error parameter.

[0039] Preferably, it also includes:

[0040] An initial vector acquisition unit is used to acquire the rotation center and rotation radius of the B and C axes and calculate the initial equivalent rotation vector after constructing the measurement coordinate system;

[0041] A rotation amount calculation unit is used to solve the rotation amounts of the B and C axes according to the collected target end posture information and the initial equivalent rotation vector to obtain the posture information;

[0042] The posture error calculation unit is used to calculate the errors of the B, C, X, Y, and Z axes respectively based on the posture information and the collected terminal X, Y, and Z axis position information to obtain the preset axis posture error and the preset axis position error.

[0043] A third aspect of the present application provides a posture decoupling kinematic calibration device, the device comprising a processor and a memory;

[0044] The memory is used to store program codes and transmit the program codes to the processor;

[0045] The processor is used to execute the posture decoupling kinematic calibration method described in the first aspect according to the instructions in the program code.

[0046] A fourth aspect of the present application provides a computer-readable storage medium, which is used to store program code, and the program code is used to execute the posture decoupling kinematic calibration method described in the first aspect.

[0047] It can be seen from the above technical solutions that the embodiments of the present application have the following advantages:

[0048] In the present application, a posture decoupling kinematic calibration method is provided, including: constructing a posture decoupling motion model based on equivalent rotation vectors and rigid body motion transformation rules; introducing posture errors, and performing posture space decomposition through the posture decoupling motion model to obtain posture error expressions and position equivalent expressions; analyzing the coupling effect of posture changes on position based on the posture error expressions and position equivalent expressions to obtain posture coupling increments; constructing a target decoupling calibration model based on the posture coupling increments and the initial decoupling calibration model, and the initial decoupling calibration model is constructed based on the posture decoupling motion model; using the least squares method to solve the geometric errors of different degrees of freedom of the target decoupling calibration model based on the preset axis posture errors to obtain the calibration error.

[0049] The posture decoupling kinematic calibration method provided by the present application proposes a posture decoupling calibration scheme based on an equivalent rotation vector, which not only spatially decomposes the posture through the posture decoupling motion model to obtain independent expressions of posture and position motion, but also analyzes the coupling effect of posture on position based on the independent expression model to obtain accurate posture coupling increments; then adjust the calibration model according to the posture coupling increment and solve it; the accuracy of the geometric errors of different degrees of freedom obtained by the solution can be ensured, because the separated posture and position errors can reach their own convergence, and the position motion is not affected by the coupling; so this process can ensure that the optimal calibration is achieved and the error compensation requirements are met. Therefore, the present application can solve the technical problem that the prior art does not consider the influence of posture on position in a multi-degree-of-freedom motion system, and it is difficult to eliminate the error difference between different degrees of freedom, resulting in poor calibration and compensation effects. BRIEF DESCRIPTION OF THE DRAWINGS

[0050] Figure 1 A schematic diagram of a flow chart of a posture decoupling kinematic calibration method provided in an embodiment of the present application;

[0051] Figure 2 A schematic diagram of the structure of a posture decoupling kinematic calibration device provided in an embodiment of the present application;

[0052] Figure 3 A schematic diagram of the construction process of a posture decoupled motion model based on an equivalent rotation vector provided in an embodiment of the present application;

[0053] Figure 4 A schematic diagram of the posture structure principle based on the posture decoupling motion model provided in an embodiment of the present application. DETAILED DESCRIPTION

[0054] In order to enable those skilled in the art to better understand the solution of the present application, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0055] For easier understanding, see Figure 1 , an embodiment of a posture decoupling kinematic calibration method provided by the present application includes:

[0056] Step 101: construct a posture decoupled motion model based on equivalent rotation vectors and rigid body motion transformation rules.

[0057] See also Figure 3 , the posture change of the end effector can be regarded as the posture matrix Left multiply the equivalent rotation vector , specifically expressed as:

[0058]

[0059] in, is the vector after the posture change, is the equivalent rotation vector. When the B-axis and C-axis rotation angles are used to describe the rotation, the change in the end effector point can be expressed as:

[0060]

[0061] in, , , Represents the standard rotation matrix around the Y axis and Z axis respectively. When , the following equation holds:

[0062]

[0063] Solving the equation, we can get the C-axis rotation, that is, the attitude angle :

[0064]

[0065] in, is a symbolic variable used to express different posture angles.

[0066] Amount of rotation on C axis Based on this, we can get the rotation of the B axis, that is, the attitude angle is :

[0067]

[0068] Then the posture decoupling motion model constructed based on the equivalent rotation vector can be expressed as:

[0069]

[0070] in, represents the position parameter component, is the equivalent rotation vector, which can be the initial value or the variable value of the calculation change process. , The rotation matrices are respectively composed of the rotation amounts of the B axis and the C axis; , Represent the equivalent postures of the B and C axes respectively; , They respectively represent the attitude errors calculated by the equivalent rotation vector.

[0071] Step 102: introduce posture error, perform posture space decomposition through posture decoupling motion model, and obtain posture error expression and position equivalent expression.

[0072] Further, step 102 includes:

[0073] Introducing posture error into the posture decoupled motion model, constructing the error decoupled motion model;

[0074] The attitude error is quantified through the error decoupling motion model to obtain the attitude error expression;

[0075] Perform equivalent rotation vector operation on the error decoupling motion model to obtain the equivalent position expression.

[0076] It should be noted that after the introduction of posture error, the posture decoupled motion model can be expressed as the error decoupled motion model:

[0077]

[0078] in, is the total position error, Indicates the theoretical position, is the position error associated with the position parameter, , They represent the attitude error, , They respectively represent the attitude angle errors calculated by the equivalent rotation vector.

[0079] Based on the above model, the specific attitude error value can be quantified, and the attitude error expression can be obtained:

[0080]

[0081] in, represents the geometric parameters related to the posture, is the theoretical geometric parameter related to the posture, Represents the geometric parameter error related to the posture.

[0082] By calculating the equivalent rotation vector of the above model, we can get the equivalent position expression:

[0083]

[0084] in, The theoretical position representing the position rigid body motion transformation rule, Represents the geometric parameters related to posture in the rigid body motion transformation rules, , They represent the theoretical geometric parameters and geometric parameter errors related to posture in the rigid body motion transformation rules, , They represent the theoretical attitude and attitude error in the posture decoupled motion model, respectively, and .

[0085] Step 103: Analyze the coupling effect of the posture change on the position based on the posture error expression and the position equivalent expression to obtain the posture coupling increment.

[0086] According to the above two expressions, we can analyze the coupling effect of posture change on position, which is specifically expressed as the position coupling increment caused by posture change, that is, the posture coupling increment:

[0087]

[0088] Through the posture decoupling motion model, the posture can be decoupled into independent expressions in space. Then, on this basis, the position coupling increment caused by the posture change is analyzed, and the influence expression model under the decoupling of posture and position is established. Since the posture and position are expressed independently, all the two can converge in their respective metric spaces to achieve the purpose of optimal error compensation; and this application also takes into account the coupling effect of posture on position, so it can ensure that the calibration process conforms to the actual situation and the calibration effect is better.

[0089] Step 104: construct a target decoupling calibration model according to the posture coupling increment and the initial decoupling calibration model, and the initial decoupling calibration model is constructed according to the posture decoupling motion model.

[0090] For the posture decoupling process of the posture decoupling motion model based on the equivalent rotation vector, please refer to Figure 4 , the process takes into account the influence of the posture coupling increment. The specific process is to build the initial decoupling calibration model based on the posture decoupling motion model:

[0091]

[0092] in, is the terminal attitude error vector after data collection and conversion, , They represent the B-axis attitude error and C-axis attitude error after data acquisition and conversion, respectively. is the attitude error mapping matrix, , Represent the error mapping matrices of the B-axis and C-axis respectively, Represents the geometric parameter error related to the attitude; is the end position error, where , , Indicates the position error of the X, Y, and Z axes, is the position error mapping matrix, , , Represent the error mapping matrices of X, Y, and Z respectively; Represents the geometric parameter error related to the position.

[0093] Considering that position errors are divided into two types, one is the error caused by attitude change, and the other is the error caused by the inherent error of position geometric parameters. This embodiment considers the coupling effect of attitude and position, and can remove the remaining position error after the attitude is coupled to the position increment:

[0094]

[0095] in, is the posture coupling increment, is the end position error. After coupling adjustment, the target decoupling calibration model is expressed as:

[0096]

[0097] in, Represents the remaining position error after removing the coupled increment of attitude to position.

[0098] Step 105: Use the least square method to solve the geometric errors of different degrees of freedom of the target decoupling calibration model according to the preset axis posture error to obtain the calibration error.

[0099] Further, step 105 includes:

[0100] The preset axis posture error includes the preset axis attitude error and the preset axis position error;

[0101] The least square method is used to solve the attitude geometric error parameters according to the preset axis attitude error and the target decoupling calibration model;

[0102] The coupling effect of the attitude change on the position is evaluated according to the attitude geometric error parameters, and the coupling increment parameters are obtained;

[0103] The least square method is used to solve the position geometry error parameters according to the coupling increment parameters and the target decoupling calibration model to obtain the calibration error. The calibration error includes attitude geometry error parameters and position geometry error parameters.

[0104] Furthermore, step 105, before that, also includes:

[0105] After constructing the measurement coordinate system, obtain the rotation center and rotation radius of the B and C axes, and calculate the initial equivalent rotation vector;

[0106] Solve the rotation amounts of the B and C axes according to the collected target end position information and the initial equivalent rotation vector to obtain the attitude information;

[0107] Based on the posture information and the collected terminal X, Y, Z axis position information, the errors of the B, C, X, Y, and Z axes are calculated respectively to obtain the preset axis posture error and the preset axis position error.

[0108] It should be noted that the formula for solving the target decoupling calibration model can be expressed as:

[0109]

[0110] After the target decoupling calibration model is successfully constructed, the solution calculation needs to be based on the preset axis posture error, that is, the preset axis posture error and the preset axis position error. These two parameters are pre-calculated data. The specific process includes constructing a measurement coordinate system, moving along the X-axis and Y-axis, and establishing the measurement coordinate system through linear fitting. ; Then, the rotation trajectory of the B-axis and C-axis can be obtained through the measurement system, so as to obtain the rotation center of the B-axis and C-axis, and the rotation path of the B-axis and C-axis and the radius of the B-axis can be obtained through circular fitting. , the intersection of the B and C axis rotation paths is used as the measuring head, which will be used as initial parameters for subsequent calculations. In addition to obtaining the rotation parameters of the B and C axes, it is also necessary to collect some initial projection components to calculate the initial equivalent rotation vector; take the coordinates of the measuring head to the C axis rotation center , as the projection components in the X and Y directions , , combined with the radius of the B axis Calculate the projection component of the Z axis , the calculated initial equivalent rotation vector is expressed as follows:

[0111]

[0112] In addition, a visual system or laser tracker is required to collect the terminal position information, including the attitude matrix and the position matrix ; According to the posture matrix The information and the initial equivalent rotation vector can be used to solve the actual rotation and theoretical rotation of the B-axis and C-axis, that is, the attitude information. The difference between the actual rotation and the theoretical rotation can be used to calculate the attitude error of the end. . The actual position matrix , that is, the position error of the end can be calculated by subtracting the axis position information from the theoretical position ; This is the preset axis attitude error and preset axis position error.

[0113] According to the solved preset axis attitude error, the attitude geometric error parameter can be solved, that is, the solution formula (a) of the target decoupling calibration model; and according to the solved attitude geometric error parameter, the coupling effect of attitude change on position can be evaluated to obtain the coupling increment parameter; combined with the coupling increment parameter and the preset axis position error, the solution formula (b) of the target decoupling calibration model can be solved to obtain the position geometric error parameter. The attitude geometric error parameter and the position geometric error parameter are the calibration error; based on the calibration error, the best calibration can be achieved and the optimal error compensation can be satisfied.

[0114] The posture decoupling kinematic calibration method provided in the embodiment of the present application proposes a posture decoupling calibration scheme based on an equivalent rotation vector, which not only spatially decomposes the posture through the posture decoupling motion model to obtain independent expressions of posture and position motion, but also analyzes the coupling effect of posture on position based on the independent expression model to obtain accurate posture coupling increments; then adjust the calibration model according to the posture coupling increment and solve it; the accuracy of the geometric errors of different degrees of freedom obtained by the solution can be ensured, because the separated posture and position errors can reach their own convergence, and the position motion is not affected by the coupling; so this process can ensure that the optimal calibration is achieved and the error compensation requirements are met. Therefore, the embodiment of the present application can solve the technical problem that the prior art does not consider the influence of posture on position in a multi-degree-of-freedom motion system, and it is difficult to eliminate the error difference between different degrees of freedom, resulting in poor calibration and compensation effects.

[0115] For easier understanding, see Figure 2 , the present application provides an embodiment of a posture decoupling kinematic calibration device, comprising:

[0116] A model building unit 201 is used to build a posture decoupled motion model based on an equivalent rotation vector and a rigid body motion transformation rule;

[0117] A posture decomposition unit 202 is used to introduce a posture error, perform posture space decomposition through a posture decoupling motion model, and obtain a posture error expression and a position equivalent expression;

[0118] A coupling analysis unit 203 is used to analyze the coupling effect of the posture change on the position according to the posture error expression and the position equivalent expression to obtain the posture coupling increment;

[0119] A model adjustment unit 204, configured to construct a target decoupling calibration model according to a posture coupling increment and an initial decoupling calibration model, wherein the initial decoupling calibration model is constructed according to the posture decoupling motion model;

[0120] The calibration solving unit 205 is used to solve the geometric errors of different degrees of freedom of the target decoupling calibration model according to the preset axis posture error by using the least square method to obtain the calibration error.

[0121] Furthermore, the posture decomposition unit 202 is specifically used for:

[0122] Introducing posture error into the posture decoupled motion model, constructing the error decoupled motion model;

[0123] The attitude error is quantified through the error decoupling motion model to obtain the attitude error expression;

[0124] Perform equivalent rotation vector operation on the error decoupling motion model to obtain the equivalent position expression.

[0125] Furthermore, the calibration solution unit 205 is specifically used for:

[0126] The preset axis posture error includes the preset axis attitude error and the preset axis position error;

[0127] The least square method is used to solve the attitude geometric error parameters according to the preset axis attitude error and the target decoupling calibration model;

[0128] The coupling effect of the attitude change on the position is evaluated according to the attitude geometric error parameters, and the coupling increment parameters are obtained;

[0129] The least square method is used to solve the position geometry error parameters according to the coupling increment parameters and the target decoupling calibration model to obtain the calibration error. The calibration error includes attitude geometry error parameters and position geometry error parameters.

[0130] Furthermore, it also includes:

[0131] The initial vector acquisition unit 206 is used to acquire the rotation center and rotation radius of the B and C axes and calculate the initial equivalent rotation vector after constructing the measurement coordinate system;

[0132] The rotation amount calculation unit 207 is used to solve the rotation amounts of the B and C axes according to the collected target end posture information and the initial equivalent rotation vector to obtain the posture information amount;

[0133] The posture error calculation unit 208 is used to calculate the errors of the B, C, X, Y, and Z axes respectively based on the posture information and the collected terminal X, Y, and Z axis position information to obtain the preset axis posture error and the preset axis position error.

[0134] The present application also provides a posture decoupling kinematic calibration device, the device comprising a processor and a memory;

[0135] The memory is used to store the program code and transmit the program code to the processor;

[0136] The processor is used to execute the posture decoupling kinematic calibration method in the above method embodiment according to the instructions in the program code.

[0137] The present application also provides a computer-readable storage medium, which is used to store program code, and the program code is used to execute the posture decoupling kinematic calibration method in the above method embodiment.

[0138] In the several embodiments provided in the present application, it should be understood that the disclosed devices and methods can be implemented in other ways. For example, the device embodiments described above are only schematic. For example, the division of the units is only a logical function division. There may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0139] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0140] In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of software functional units.

[0141] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application is essentially or the part that contributes to the prior art or all or part of the technical solution can be embodied in the form of a software product. The computer software product is stored in a storage medium, including a number of instructions for executing all or part of the steps of the method described in each embodiment of the present application through a computer device (which can be a personal computer, server, or network device, etc.). The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (full name in English: Read-Only Memory, English abbreviation: ROM), random access memory (full name in English: Random Access Memory, English abbreviation: RAM), disk or optical disk and other media that can store program codes.

[0142] As described above, the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A posture decoupling kinematic calibration method, characterized in that: include: A posture decoupled motion model is constructed based on the equivalent rotation vector and rigid body motion transformation rules. The posture decoupled motion model can be expressed as: in, is the theoretical position, ΛQ represents the position parameter component, V vec is the equivalent rotation vector, which is the initial value or the variable value of the calculation change process. are the rotation matrices composed of the rotations of the B axis and the C axis respectively; equ , C equ Represent the equivalent postures of the B and C axes respectively; Respectively represent the attitude errors calculated by the equivalent rotation vector; Introducing a posture error, performing posture space decomposition through the posture decoupling motion model, and obtaining a posture error expression and a position equivalent expression; According to the attitude error expression and the position equivalent expression, the coupling effect of attitude change on position is analyzed to obtain the attitude coupling increment, which is expressed as: Among them, Ω and ΔΩ represent the theoretical attitude and attitude error in the posture decoupling motion model, respectively, and Constructing a target decoupling calibration model according to the posture coupling increment and the initial decoupling calibration model, wherein the initial decoupling calibration model is constructed according to the posture decoupling motion model; The least square method is used to solve the geometric errors of different degrees of freedom of the target decoupling calibration model according to the preset axis posture error to obtain the calibration error.

2. The posture decoupling kinematic calibration method according to claim 1, characterized in that: The posture error is introduced, and the posture space is decomposed by the posture decoupling motion model to obtain the posture error expression and the position equivalent expression, including: Introducing a posture error into the posture decoupling motion model to construct an error decoupling motion model; The attitude error is quantified by the error decoupling motion model to obtain an attitude error expression; An equivalent rotation vector operation is performed on the error decoupling motion model to obtain an equivalent position expression.

3. The posture decoupling kinematic calibration method according to claim 1, characterized in that: The least square method is used to solve the geometric errors of different degrees of freedom of the target decoupling calibration model according to the preset axis posture error to obtain the calibration error, including: The preset axis posture error includes a preset axis attitude error and a preset axis position error; Using the least square method to solve the attitude geometric error parameters according to the preset axis attitude error and the target decoupling calibration model; Evaluate the coupling effect of the attitude change on the position according to the attitude geometric error parameter to obtain a coupling increment parameter; The least square method is adopted to solve the position geometry error parameter according to the coupling increment parameter and the target decoupling calibration model to obtain the calibration error, wherein the calibration error includes the attitude geometry error parameter and the position geometry error parameter.

4. The posture decoupling kinematic calibration method according to claim 1, characterized in that: The method adopts the least square method to solve the geometric errors of different degrees of freedom of the target decoupling calibration model according to the preset axis posture error to obtain the calibration error, and the method also includes: After constructing the measurement coordinate system, obtain the rotation center and rotation radius of the B and C axes, and calculate the initial equivalent rotation vector; Solve the rotation amounts of the B and C axes according to the collected target end position information and the initial equivalent rotation vector to obtain the attitude information; Based on the posture information and the collected terminal X, Y, Z axis position information, the errors of the B, C, X, Y, and Z axes are calculated respectively to obtain the preset axis posture error and the preset axis position error.

5. A posture decoupling kinematic calibration device, characterized in that: include: The model building unit is used to build a posture decoupled motion model based on an equivalent rotation vector and a rigid body motion transformation rule. The posture decoupled motion model can be expressed as: in, is the theoretical position, ΛQ represents the position parameter component, V vec is the equivalent rotation vector, which is the initial value or the variable value of the calculation change process. are the rotation matrices composed of the rotations of the B axis and the C axis respectively; equ , C equ Represent the equivalent postures of the B and C axes respectively; Respectively represent the attitude errors calculated by the equivalent rotation vector; A posture decomposition unit is used to introduce a posture error, perform posture space decomposition through the posture decoupling motion model, and obtain a posture error expression and a position equivalent expression; A coupling analysis unit is used to analyze the coupling effect of the posture change on the position according to the posture error expression and the position equivalent expression, and obtain the posture coupling increment, and the posture coupling increment is expressed as: Among them, Ω and ΔΩ represent the theoretical attitude and attitude error in the posture decoupling motion model, respectively, and A model adjustment unit, configured to construct a target decoupling calibration model according to the posture coupling increment and an initial decoupling calibration model, wherein the initial decoupling calibration model is constructed according to the posture decoupling motion model; The calibration solving unit is used to solve the geometric errors of different degrees of freedom of the target decoupling calibration model according to the preset axis posture error by using the least square method to obtain the calibration error.

6. The posture decoupling kinematic calibration device according to claim 5, characterized in that: The posture decomposition unit is specifically used for: Introducing a posture error into the posture decoupling motion model to construct an error decoupling motion model; The attitude error is quantified by the error decoupling motion model to obtain an attitude error expression; An equivalent rotation vector operation is performed on the error decoupling motion model to obtain an equivalent position expression.

7. The posture decoupling kinematic calibration device according to claim 5, characterized in that: The calibration solution unit is specifically used for: The preset axis posture error includes a preset axis attitude error and a preset axis position error; Using the least square method to solve the attitude geometric error parameters according to the preset axis attitude error and the target decoupling calibration model; Evaluate the coupling effect of the attitude change on the position according to the attitude geometric error parameter to obtain a coupling increment parameter; The least square method is adopted to solve the position geometry error parameter according to the coupling increment parameter and the target decoupling calibration model to obtain the calibration error, wherein the calibration error includes the attitude geometry error parameter and the position geometry error parameter.

8. The posture decoupling kinematic calibration device according to claim 5, characterized in that: Also includes: An initial vector acquisition unit is used to acquire the rotation center and rotation radius of the B and C axes and calculate the initial equivalent rotation vector after constructing the measurement coordinate system; A rotation amount calculation unit is used to solve the rotation amounts of the B and C axes according to the collected target end posture information and the initial equivalent rotation vector to obtain the posture information; The posture error calculation unit is used to calculate the errors of the B, C, X, Y, and Z axes respectively based on the posture information and the collected terminal X, Y, and Z axis position information to obtain the preset axis posture error and the preset axis position error.

9. A posture decoupling kinematic calibration device, characterized in that: The device comprises a processor and a memory; The memory is used to store program code and transmit the program code to the processor; The processor is used to execute the posture decoupling kinematic calibration method described in any one of claims 1-4 according to the instructions in the program code.

10. A computer-readable storage medium, characterized in that: The computer-readable storage medium is used to store program code, and the program code is used to execute the posture decoupling kinematic calibration method described in any one of claims 1-4.

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