Pose-decoupled kinematic calibration method, apparatus and device, and storage medium

Abstract

A pose-decoupled kinematic calibration method, apparatus and device, and a storage medium. The method comprises: constructing a pose-decoupled motion model on the basis of an equivalent rotation vector and a rigid body motion transformation rule (101); introducing a pose error, and performing pose space decomposition by means of the pose-decoupled motion model to obtain an orientation error expression and a position equivalent expression (102); analyzing the coupling effect of an orientation change on a position on the basis of the orientation error expression and the position equivalent expression so as to obtain a pose coupling increment (103); constructing a target decoupled calibration model on the basis of the pose coupling increment and an initial decoupled calibration model, wherein the initial decoupled calibration model is constructed on the basis of the pose-decoupled motion model (104); and using the least squares method to perform geometric error calculation of different degrees of freedom on the target decoupled calibration model on the basis of preset axial pose errors, so as to obtain a calibration error (105). The method can solve the technical problem in the prior art that the influence of an orientation on a position in a multi-degree-of-freedom motion system is not considered, making it is difficult to eliminate an error difference between different degrees of freedom, and thus resulting in poor calibration and compensation effects.

Description

A method, apparatus, device, and storage medium for pose decoupling kinematic calibration. Technical Field

[0001] This application relates to the field of mechanical motion technology, and in particular to a method, apparatus, device and storage medium for posture decoupling kinematic calibration. Background Technology

[0002] Component machining requires complex shapes, large dimensions, and high precision, necessitating improvements in the machining stroke and operational accuracy of multi-axis manufacturing equipment to meet various complex demands. Five-axis machining, with its attitude adjustment capabilities, is widely applicable to complex surface machining, and its absolute positioning accuracy is the most critical performance indicator. Kinematic geometry error calibration is one effective way to improve the absolute positioning accuracy of multi-degree-of-freedom motion systems. In machining applications where both position and attitude require high precision, current technologies primarily employ the method of minimizing overall pose error for calibration. However, due to differences in the dimensions, values, and measurement accuracy of position and attitude, geometric error differences arise between different degrees of freedom, leading to weak convergence of some attitude errors. This makes it difficult for the overall calibration method to achieve optimal compensation for position and attitude.

[0003] While current calibration methods separate the attitude and position matrices within the homogeneous transformation matrix at the end point, they do not evaluate the influence of attitude on position. Therefore, the position matrix still contains coupling between position and attitude parameters. Because these methods cannot consider the impact of attitude on position, it remains difficult to achieve optimal calibration and corresponding error compensation for each degree of freedom of the mechanism. Summary of the Invention

[0004] This application provides a pose decoupling kinematic calibration method, apparatus, device, and storage medium 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, making it difficult to eliminate the error differences between different degrees of freedom, resulting in poor calibration and compensation effects.

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

[0006] A pose-decoupled motion model is constructed based on equivalent rotation vectors and rigid body motion transformation rules;

[0007] By introducing pose error, pose space decomposition is performed through the pose decoupled motion model to obtain the pose error expression and the position equivalent expression;

[0008] The coupling effect of attitude change on position is analyzed based on the attitude error expression and the position equivalent expression to obtain the pose coupling increment;

[0009] A target decoupling calibration model is constructed based on the pose coupling increment and the initial decoupling calibration model, wherein the initial decoupling calibration model is constructed based on the pose decoupling motion model.

[0010] The least squares method is used to solve for the geometric errors of the target decoupled calibration model with different degrees of freedom based on the preset axis pose error, and the calibration error is obtained.

[0011] Preferably, the introduction of pose error, and the decomposition of pose space through the pose decoupled motion model to obtain the pose error expression and the position equivalent expression, includes:

[0012] A pose error is introduced into the pose decoupled motion model to construct an error decoupled motion model.

[0013] The attitude error is quantified and expressed using the aforementioned error decoupling motion model, resulting in an attitude error expression.

[0014] The equivalent rotation vector operation is performed on the error decoupled motion model to obtain the position equivalent expression.

[0015] Preferably, the step of using the least squares method to solve for the geometric errors of the target decoupling calibration model with different degrees of freedom based on the preset axis pose error to obtain the calibration error includes:

[0016] The preset axis pose error includes the preset axis pose error and the preset axis position error;

[0017] The attitude geometric error parameters are solved using the least squares method based on the preset axis attitude error and the target decoupling calibration model.

[0018] The degree of coupling influence of attitude change on position is evaluated based on the attitude geometric error parameters to obtain the coupling increment parameters;

[0019] The position geometric error parameters are solved using the least squares method based on the coupling increment parameters and the target decoupling calibration model to obtain the calibration error, which includes the attitude geometric error parameters and the position geometric error parameters.

[0020] Preferably, the step of using the least squares method to solve for the geometric errors of the target decoupling calibration model with different degrees of freedom based on the preset axis pose error to obtain the calibration error further includes:

[0021] After establishing the measurement coordinate system, obtain the rotation centers and radii of the B and C axes, and calculate the initial equivalent rotation vector;

[0022] Based on the collected target end pose information and the initial equivalent rotation vector, the rotation amounts of the B and C axes are calculated to obtain the attitude information.

[0023] Based on the attitude information and the acquired end-point 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 attitude error and preset axis position error.

[0024] A second aspect of this application provides a pose decoupling kinematic calibration device, comprising:

[0025] The model building unit is used to construct a pose-decoupled motion model based on the equivalent rotation vector and rigid body motion transformation rules.

[0026] The pose decomposition unit is used to introduce pose error and perform pose space decomposition through the pose decoupled motion model to obtain the pose error expression and the position equivalent expression.

[0027] The coupling analysis unit is used to analyze the coupling effect of attitude change on position based on the attitude error expression and the position equivalent expression, and to obtain the pose coupling increment.

[0028] The model adjustment unit is used to construct a target decoupling calibration model based on the pose coupling increment and the initial decoupling calibration model, wherein the initial decoupling calibration model is constructed based on the pose decoupling motion model.

[0029] The calibration solution unit is used to solve the geometric error of the target decoupled calibration model with different degrees of freedom based on the preset axis pose error using the least squares method, so as to obtain the calibration error.

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

[0031] A pose error is introduced into the pose decoupled motion model to construct an error decoupled motion model.

[0032] The attitude error is quantified and expressed using the aforementioned error decoupling motion model, resulting in an attitude error expression.

[0033] The equivalent rotation vector operation is performed on the error decoupled motion model to obtain the position equivalent expression.

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

[0035] The preset axis pose error includes the preset axis pose error and the preset axis position error;

[0036] The attitude geometric error parameters are solved using the least squares method based on the preset axis attitude error and the target decoupling calibration model.

[0037] The degree of coupling influence of attitude change on position is evaluated based on the attitude geometric error parameters to obtain the coupling increment parameters;

[0038] The position geometric error parameters are solved using the least squares method based on the coupling increment parameters and the target decoupling calibration model to obtain the calibration error, which includes the attitude geometric error parameters and the position geometric error parameters.

[0039] Preferably, it further includes:

[0040] The initial vector acquisition unit is used to acquire the rotation centers and radii of the B and C axes after establishing the measurement coordinate system, and to calculate the initial equivalent rotation vector;

[0041] The rotation calculation unit is used to calculate the rotation of the B and C axes based on the collected target end pose information and the initial equivalent rotation vector to obtain the attitude information.

[0042] The pose error calculation unit is used to calculate the errors of the B, C, X, Y, and Z axes based on the pose information and the acquired end-effector X, Y, and Z axis position information, respectively, to obtain the preset axis pose error and preset axis position error.

[0043] A third aspect of this application provides a pose decoupling kinematics calibration device, the device including a processor and a memory;

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

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

[0046] A fourth aspect of this application provides a computer-readable storage medium for storing program code for performing the pose decoupling kinematic calibration method described in the first aspect.

[0047] As can be seen from the above technical solutions, the embodiments of this application have the following advantages:

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

[0049] The pose decoupling kinematic calibration method provided in this application proposes a pose decoupling calibration scheme based on equivalent rotation vectors. This scheme not only spatially decomposes the pose using a pose decoupling motion model to obtain independent expressions of attitude and position motion, but also analyzes the coupling effect of attitude on position based on the independent expression model, obtaining accurate pose coupling increments. Then, the calibration model is adjusted based on the pose coupling increments and solved. This ensures the accuracy of the geometric errors of different degrees of freedom obtained from the solution, because the separated attitude and position errors can converge independently, and the position motion is unaffected by coupling. Therefore, this process ensures optimal calibration and meets error compensation requirements. Thus, this application solves the technical problem in existing technologies that do not consider the influence of attitude on position in multi-degree-of-freedom motion systems, making it difficult to eliminate error differences between different degrees of freedom, resulting in poor calibration and compensation effects. Attached Figure Description

[0050] Figure 1 is a schematic flowchart of a pose decoupling kinematic calibration method provided in an embodiment of this application;

[0051] Figure 2 is a schematic diagram of a pose decoupling kinematic calibration device provided in an embodiment of this application;

[0052] Figure 3 is a schematic diagram of the construction process of the pose decoupling motion model based on the equivalent rotation vector provided in the embodiment of this application;

[0053] Figure 4 is a schematic diagram of the pose structure principle based on the pose decoupling motion model provided in the embodiment of this application. Detailed Implementation

[0054] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present application, and not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present application.

[0055] For ease of understanding, please refer to Figure 1. An embodiment of a pose decoupling kinematic calibration method provided in this application includes:

[0056] Step 101: Construct a pose decoupled motion model based on the equivalent rotation vector and rigid body motion transformation rules.

[0057] Referring to Figure 3, the pose change of the end effector can be viewed as left-multiplying the pose matrix ∏R by the equivalent rotation vector V. vec Specifically, it can be expressed as: V'=[∏R]V vec

[0058] Where, V' = [v' x ,v' y ,v' z ] is the vector after the attitude change, V vec =[x vec ,y vec ,z vec ] is the equivalent rotation vector. When rotating using the B-axis and C-axis rotation angles, the change in the end effector point can be expressed as: R B R C V vec =V”

[0059] Where, V”=[v' x ',v' y ',v' z '], R B R C Let V' and V' represent the standard rotation matrices around the Y-axis and Z-axis, respectively. When V' = V", the following equation holds: R B R C V vec =[∏R]V vec

[0060] Solving the equations yields the C-axis rotation, i.e., the attitude angle.

[0061] Here, μ is a symbolic variable used to express different attitude angles.

[0062] Rotation along the C-axis Based on this, the rotation of the B-axis, i.e., the attitude angle, can be obtained.

[0063] Therefore, the pose decoupled motion model constructed based on the equivalent rotation vector can be expressed as:

[0064] Where ΛQ represents the position parameter components, V vec The equivalent rotation vector can be an initial value or a variable value used to calculate the change process. The rotation matrices are formed by the rotation amounts along the B-axis and C-axis, respectively; B equ C equ These represent the equivalent attitudes of the B and C axes, respectively. These represent the attitude errors calculated using the equivalent rotation vector.

[0065] Step 102: Introduce pose error, and decompose the pose space through the pose decoupling motion model to obtain the pose error expression and the position equivalent expression.

[0066] Further, step 102 includes:

[0067] Introduce pose error into the pose decoupled motion model to construct an error decoupled motion model;

[0068] The attitude error is quantified and expressed by the error decoupling motion model, resulting in the attitude error expression.

[0069] Equivalent rotation vector calculations are performed on the error-decoupled motion model to obtain the position equivalent expression.

[0070] It should be noted that, after introducing pose error, the pose decoupled motion model can be expressed as an error decoupled motion model:

[0071] in, This represents the total position error. The theoretical position is represented by Δ(ΛQ), the position error related to the position parameters is ΔB. equ ΔC equ These represent attitude errors, These represent the attitude angle errors calculated using the equivalent rotation vector.

[0072] Based on the above model, the specific attitude error value can be quantified to obtain the attitude error expression:

[0073] Among them, L Ω Represents the geometric parameters related to attitude. These are theoretical geometric parameters related to attitude. This represents the geometric parameter error related to attitude.

[0074] By performing equivalent rotation vector calculations on the above model, the equivalent position expression can be obtained:

[0075] in, L represents the theoretical position according to the rules of rigid body motion transformation. Ω Represents the geometric parameters related to attitude in the rigid body motion transformation rules. Let represent the theoretical geometric parameters and geometric parameter errors related to attitude in the rigid body motion transformation rules, respectively; and Ω and ΔΩ represent the theoretical attitude and attitude error in the pose decoupled motion model, respectively.

[0076] Step 103: Analyze the coupling effect of attitude change on position based on the attitude error expression and the position equivalent expression to obtain the pose coupling increment.

[0077] Based on the above two expressions, we can analyze the coupling effect of attitude change on position, specifically expressed as the position coupling increment caused by attitude change, i.e., pose coupling increment:

[0078] By using a pose-decoupled motion model, pose can be spatially decoupled into independent representations. Based on this, the position coupling increment caused by pose changes is analyzed, and an impact representation model is established for the decoupled pose and position. Since pose and position are independently represented, they can converge in their respective metric spaces, achieving optimal error compensation. Furthermore, this application considers the coupling effect of pose on position, thus ensuring that the calibration process conforms to actual conditions and yields better calibration results.

[0079] Step 104: Construct the target decoupling calibration model based on the pose coupling increment and the initial decoupling calibration model. The initial decoupling calibration model is constructed based on the pose decoupling motion model.

[0080] The pose decoupling process of the pose decoupling motion model based on the equivalent rotation vector is shown in Figure 4. This process considers the influence of the pose coupling increment. Specifically, the initial decoupling calibration model is constructed based on the pose decoupling motion model:

[0081] Where, ΔΩ B,C =[ΔBΔC] T Let J be the end-effector attitude error vector after data acquisition and conversion, where ΔB and ΔC represent the B-axis attitude error and C-axis attitude error after data acquisition and conversion, respectively. Ω =[J B J C ] T J is the attitude error mapping matrix. B J C Let ΔL represent the error mapping matrices for the B-axis and C-axis, respectively. Ω Indicates the attitude-related geometric parameter error; ΔP X Y, Z = [ΔX ΔY ΔZ] T The term refers to the end-position error, where ΔX, ΔY, and ΔZ represent the position errors of the X, Y, and Z axes, respectively, and J is the end-position error. P =[J X J Y J Z ] T J is the position error mapping matrix. X J Y J Z Let ΔL represent the error mapping matrices for X, Y, and Z, respectively; P This represents the position-related geometric parameter error.

[0082] Position errors are categorized into two types: errors caused by attitude changes and errors caused by inherent errors in position geometric parameters. This embodiment considers the coupling effect between attitude and position, and can remove the residual position error after the attitude-position coupling increment.

[0083] in, This is the pose coupling increment, ΔP X,Y,Z This represents the end-position error. After coupling adjustment, the resulting target decoupling calibration model is expressed as:

[0084] Where, ΔP RES This represents the remaining position error after removing the attitude-position coupling increment.

[0085] Step 105: Using the least squares method, the geometric error of the target decoupling calibration model with different degrees of freedom is solved based on the preset axis pose error to obtain the calibration error.

[0086] Further, step 105 includes:

[0087] Preset axis pose error includes preset axis attitude error and preset axis position error;

[0088] The least squares method is used to solve for the attitude geometric error parameters based on the preset axis attitude error and the target decoupling calibration model.

[0089] The degree of coupling influence of attitude change on position is evaluated based on attitude geometric error parameters, and the coupling increment parameters are obtained.

[0090] The least squares method is used to solve for the position geometric error parameters based on the coupling increment parameters and the target decoupling calibration model, and the calibration error is obtained. The calibration error includes attitude geometric error parameters and position geometric error parameters.

[0091] Furthermore, step 105, preceding the following, also includes:

[0092] After establishing the measurement coordinate system, obtain the rotation centers and radii of the B and C axes, and calculate the initial equivalent rotation vector;

[0093] Based on the collected target end pose information and the initial equivalent rotation vector, the rotation amounts of the B and C axes are calculated to obtain the attitude information.

[0094] Based on the attitude information and the acquired end-point 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 attitude error and preset axis position error.

[0095] It should be noted that the formula for solving the target decoupling calibration model can be expressed as:

[0096] The solution calculation after the target decoupling calibration model is successfully constructed requires the preset axis pose error, namely the preset axis attitude 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 and Y axes, and establishing the measurement coordinate system X'Y'Z' through linear fitting. Then, the rotation trajectories of the B and C axes can be obtained through the measurement system, thus obtaining the rotation centers of the B and C axes. Finally, the rotation paths of the B and C axes and the radius L of the B axis are obtained through circular fitting. Rb The intersection of the rotation paths of the B and C axes is used as the measuring head, and these will serve as initial parameters for subsequent calculations. In addition to obtaining the rotation parameters of the B and C axes, some initial projection components need to be acquired to calculate the initial equivalent rotation vector; the coordinates O from the measuring head to the rotation center of the C axis are taken. c As the projection components in the X and Y directions, x las y las Combined with the radius L of the B-axis Rb Calculate the projection components of the Z-axis The calculated initial equivalent rotation vector is represented as follows:

[0097] In addition, a vision system or laser tracker is needed to acquire end-effector pose information, including the attitude matrix ∏R and the position matrix P. Based on the attitude matrix ∏R and the initial equivalent rotation vector, the actual and theoretical rotations of the B and C axes, i.e., the attitude information, can be calculated. Subtracting the actual and theoretical rotations yields the end-effector attitude error ΔΩ. Similarly, subtracting the actual position matrix P (axis position information) from the theoretical position yields the end-effector position error ΔP; these are the preset axis attitude error and preset axis position error.

[0098] The attitude geometric error parameters, i.e., the solution formula (a) for the target decoupling calibration model, can be obtained from the solved preset axis attitude error. The coupling effect of attitude changes on position can be evaluated based on the solved attitude geometric error parameters, yielding the coupling increment parameters. Combining the coupling increment parameters and the preset axis position error, the solution formula (b) for the target decoupling calibration model can be solved, obtaining the position geometric error parameters. These attitude and position geometric error parameters constitute the calibration error. Optimal calibration and optimal error compensation can be achieved based on these calibration errors.

[0099] The pose decoupling kinematic calibration method provided in this application proposes a pose decoupling calibration scheme based on equivalent rotation vectors. It not only spatially decomposes the pose using a pose 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, obtaining accurate pose coupling increments. Then, the calibration model is adjusted based on the pose coupling increments and solved. This ensures the accuracy of the geometric errors of different degrees of freedom obtained from the solution, because the separated posture and position errors can converge independently, and the position motion is not affected by coupling. Therefore, this process ensures optimal calibration and meets error compensation requirements. Thus, this application can solve the technical problem that existing technologies do not consider the influence of posture on position in multi-degree-of-freedom motion systems, making it difficult to eliminate error differences between different degrees of freedom, resulting in poor calibration and compensation effects.

[0100] For ease of understanding, please refer to Figure 2. This application provides an embodiment of a pose decoupling kinematic calibration device, including:

[0101] Model building unit 201 is used to build a pose decoupled motion model based on equivalent rotation vectors and rigid body motion transformation rules;

[0102] The pose decomposition unit 202 is used to introduce pose error, perform pose space decomposition through pose decoupling motion model, and obtain pose error expression and position equivalent expression.

[0103] The coupling analysis unit 203 is used to analyze the coupling effect of attitude change on position based on the attitude error expression and the position equivalent expression, and to obtain the pose coupling increment.

[0104] The model adjustment unit 204 is used to construct the target decoupling calibration model based on the pose coupling increment and the initial decoupling calibration model. The initial decoupling calibration model is constructed based on the pose decoupling motion model.

[0105] The calibration solution unit 205 is used to solve the geometric error of the target decoupled calibration model with different degrees of freedom based on the preset axis pose error using the least squares method, so as to obtain the calibration error.

[0106] Furthermore, the pose decomposition unit 202 is specifically used for:

[0107] Introduce pose error into the pose decoupled motion model to construct an error decoupled motion model;

[0108] The attitude error is quantified and expressed by the error decoupling motion model, resulting in the attitude error expression.

[0109] Equivalent rotation vector calculations are performed on the error-decoupled motion model to obtain the position equivalent expression.

[0110] Furthermore, the calibration solver unit 205 is specifically used for:

[0111] Preset axis pose error includes preset axis attitude error and preset axis position error;

[0112] The least squares method is used to solve for the attitude geometric error parameters based on the preset axis attitude error and the target decoupling calibration model.

[0113] The degree of coupling influence of attitude change on position is evaluated based on attitude geometric error parameters, and the coupling increment parameters are obtained.

[0114] The least squares method is used to solve for the position geometric error parameters based on the coupling increment parameters and the target decoupling calibration model, and the calibration error is obtained. The calibration error includes attitude geometric error parameters and position geometric error parameters.

[0115] Furthermore, it also includes:

[0116] The initial vector acquisition unit 206 is used to acquire the rotation centers and rotation radii of the B and C axes after constructing the measurement coordinate system, and to calculate the initial equivalent rotation vector;

[0117] The rotation calculation unit 207 is used to calculate the rotation of the B and C axes based on the collected target end pose information and the initial equivalent rotation vector to obtain the attitude information.

[0118] The pose error calculation unit 208 is used to calculate the errors of the B, C, X, Y, and Z axes based on the pose information and the acquired end X, Y, and Z axis position information, respectively, to obtain the preset axis pose error and the preset axis position error.

[0119] This application also provides a pose decoupling kinematics calibration device, which includes a processor and a memory;

[0120] The memory is used to store program code and transfer the program code to the processor;

[0121] The processor is used to execute the pose decoupling kinematic calibration method in the above method embodiment according to the instructions in the program code.

[0122] This application also provides a computer-readable storage medium for storing program code for executing the pose decoupling kinematic calibration method in the above method embodiments.

[0123] In the several embodiments provided in this application, it should be understood that the disclosed apparatus and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative; for instance, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be through some interfaces; the indirect coupling or communication connection between apparatuses or units may be electrical, mechanical, or other forms.

[0124] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0125] Furthermore, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0126] If the integrated unit is implemented as 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 this application, in essence, 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. This computer software product is stored in a storage medium and includes several instructions for executing all or part of the steps of the methods described in the various embodiments of this application through a computer device (which may be a personal computer, server, or network device, etc.). The aforementioned storage medium includes: USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, optical disks, and other media capable of storing program code.

[0127] The above-described embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application 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. Such 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 this application.

Claims

1. A method for pose decoupling kinematic calibration, characterized in that, include: A pose-decoupled motion model is constructed based on equivalent rotation vectors and rigid body motion transformation rules; By introducing pose error, pose space decomposition is performed through the pose decoupled motion model to obtain the pose error expression and the position equivalent expression; The coupling effect of attitude change on position is analyzed based on the attitude error expression and the position equivalent expression to obtain the pose coupling increment; A target decoupling calibration model is constructed based on the pose coupling increment and the initial decoupling calibration model, wherein the initial decoupling calibration model is constructed based on the pose decoupling motion model. The least squares method is used to solve for the geometric errors of the target decoupled calibration model with different degrees of freedom based on the preset axis pose error, and the calibration error is obtained.

2. The pose decoupling kinematic calibration method according to claim 1, characterized in that, The introduction of pose error, followed by pose space decomposition using the pose decoupled motion model, yields pose error expressions and position equivalent expressions, including: A pose error is introduced into the pose decoupled motion model to construct an error decoupled motion model. The attitude error is quantified and expressed using the aforementioned error decoupling motion model, resulting in an attitude error expression. The equivalent rotation vector operation is performed on the error decoupled motion model to obtain the position equivalent expression.

3. The pose decoupling kinematic calibration method according to claim 1, characterized in that, The least squares method is used to solve for the geometric errors of the target decoupling calibration model at different degrees of freedom based on the preset axis pose error, resulting in the calibration error, including: The preset axis pose error includes the preset axis pose error and the preset axis position error; The attitude geometric error parameters are solved using the least squares method based on the preset axis attitude error and the target decoupling calibration model. The degree of coupling influence of attitude change on position is evaluated based on the attitude geometric error parameters to obtain the coupling increment parameters; The position geometric error parameters are solved using the least squares method based on the coupling increment parameters and the target decoupling calibration model to obtain the calibration error, which includes the attitude geometric error parameters and the position geometric error parameters.

4. The pose decoupling kinematic calibration method according to claim 1, characterized in that, The step of using the least squares method to solve for the geometric errors of the target decoupled calibration model at different degrees of freedom based on the preset axis pose error to obtain the calibration error also includes: After establishing the measurement coordinate system, obtain the rotation centers and radii of the B and C axes, and calculate the initial equivalent rotation vector; Based on the collected target end pose information and the initial equivalent rotation vector, the rotation amounts of the B and C axes are calculated to obtain the attitude information. Based on the attitude information and the acquired end-point 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 attitude error and preset axis position error.

5. A pose decoupling kinematic calibration device, characterized in that, include: The model building unit is used to construct a pose-decoupled motion model based on the equivalent rotation vector and rigid body motion transformation rules. The pose decomposition unit is used to introduce pose error and perform pose space decomposition through the pose decoupled motion model to obtain the pose error expression and the position equivalent expression. The coupling analysis unit is used to analyze the coupling effect of attitude change on position based on the attitude error expression and the position equivalent expression, and to obtain the pose coupling increment. The model adjustment unit is used to construct a target decoupling calibration model based on the pose coupling increment and the initial decoupling calibration model, wherein the initial decoupling calibration model is constructed based on the pose decoupling motion model. The calibration solution unit is used to solve the geometric error of the target decoupled calibration model with different degrees of freedom based on the preset axis pose error using the least squares method, so as to obtain the calibration error.

6. The pose decoupling kinematic calibration device according to claim 5, characterized in that, The pose decomposition unit is specifically used for: A pose error is introduced into the pose decoupled motion model to construct an error decoupled motion model. The attitude error is quantified and expressed using the aforementioned error decoupling motion model, resulting in an attitude error expression. The equivalent rotation vector operation is performed on the error decoupled motion model to obtain the position equivalent expression.

7. The pose decoupling kinematic calibration device according to claim 5, characterized in that, The calibration and solving unit is specifically used for: The preset axis pose error includes the preset axis pose error and the preset axis position error; The attitude geometric error parameters are solved using the least squares method based on the preset axis attitude error and the target decoupling calibration model. The degree of coupling influence of attitude change on position is evaluated based on the attitude geometric error parameters to obtain the coupling increment parameters; The position geometric error parameters are solved using the least squares method based on the coupling increment parameters and the target decoupling calibration model to obtain the calibration error, which includes the attitude geometric error parameters and the position geometric error parameters.

8. The pose decoupling kinematic calibration device according to claim 5, characterized in that, Also includes: The initial vector acquisition unit is used to acquire the rotation centers and radii of the B and C axes after establishing the measurement coordinate system, and to calculate the initial equivalent rotation vector; The rotation calculation unit is used to calculate the rotation of the B and C axes based on the collected target end pose information and the initial equivalent rotation vector to obtain the attitude information. The pose error calculation unit is used to calculate the errors of the B, C, X, Y, and Z axes based on the pose information and the acquired end-effector X, Y, and Z axis position information, respectively, to obtain the preset axis pose error and preset axis position error.

9. A pose decoupling kinematic calibration device, characterized in that, The device includes 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 pose decoupling kinematic calibration method according to 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 for executing the pose decoupling kinematic calibration method according to any one of claims 1-4.

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