A motion control method and system for a four-point supported POGO column parallel mechanism

Abstract

The present invention relates to a motion control method and system for a four-point supported POGO column parallel mechanism, and the method comprises the following steps: constructing a kinematic calculation model of the four-point supported POGO column parallel mechanism; confirming the workpiece posture required to be adjusted for the workpiece, and generating workpiece posture data according to the workpiece posture; substituting the workpiece posture data into the kinematic calculation model to obtain posture adjustment parameter data; generating a parallel mechanism adjustment signal according to the posture adjustment parameter data; adjusting the posture of the four-point supported POGO column parallel mechanism using the parallel mechanism adjustment signal; the motion control method of the four-point supported POGO column parallel mechanism provided by the present invention has the advantages of high control accuracy, fast posture adjustment response, etc.

Description

Technical Field

[0001] The present invention relates to the technical field of engineering machinery, and in particular to a motion control method and system for a four-point supported POGO column parallel mechanism. Background Art

[0002] In the existing posture adjustment and docking assembly process of various large cabin-type structural parts, parallel posture adjustment mechanisms of different configurations are mostly used to adjust the posture of the cabin workpiece. The parallel mechanism has the advantages of large stiffness-to-weight ratio, strong load-bearing capacity, and fast response speed. However, the parallel posture adjustment assembly system based on multi-point support generally requires redundant control, which puts forward higher requirements on the control method. The function of the existing tooling system is to tighten the workpiece to be assembled, and adjust the posture of the workpiece to achieve the subsequent assembly and inspection of the workpiece. Since multi-degree-of-freedom manual fine-tuning must be performed after the initial docking and positioning of various large cabin-type structural parts to ensure the rapid and accurate docking and assembly of the cabin, it is of great significance to design a multi-degree-of-freedom cabin posture adjustment device to achieve manual fine-tuning. In the process of cabin docking and inspection, the posture of the cabin is usually adjusted manually by manual handling or auxiliary adjustment devices, but manual handling not only increases the labor intensity, but also the adjustment process is very cumbersome and slow. Summary of the invention

[0003] In order to solve the technical problems in the prior art of manually directly transporting or manually adjusting the cabin section through auxiliary devices, resulting in a cumbersome and slow adjustment process, the present invention provides a motion control method and system for a four-point support POGO column parallel mechanism.

[0004] The technical solution of the present invention to solve the above technical problems is as follows:

[0005] A motion control method for a four-point supported POGO column parallel mechanism comprises the following steps:

[0006] Constructing a kinematic calculation model of a four-point supported POGO column parallel mechanism; wherein the four-point supported POGO column parallel mechanism is used to adjust the posture of a workpiece;

[0007] Confirming the workpiece posture that needs to be adjusted for the workpiece, and generating workpiece posture data according to the workpiece posture;

[0008] Substituting the workpiece posture data into the kinematic calculation model to obtain posture adjustment parameter data;

[0009] Generate a parallel mechanism adjustment signal according to the posture adjustment parameter data;

[0010] The parallel mechanism adjustment signal is used to adjust the posture of the four-point support POGO column parallel mechanism.

[0011] The beneficial effects of the present invention are: a calculation model is established according to the kinematic characteristics of the four-point supported POGO column parallel mechanism, the posture adjustment parameters are substituted into the calculation model to calculate the posture adjustment data required by the four-point supported POGO column parallel mechanism, and the four-point supported POGO column parallel mechanism is controlled to perform posture adjustment according to the posture adjustment data. It has the advantages of high control accuracy and fast posture adjustment response, and solves the technical problems of slow traditional manual posture adjustment and complicated adjustment process.

[0012] Based on the above technical solution, the present invention can also be improved as follows.

[0013] Furthermore, a kinematic calculation model of a four-point supported POGO column parallel mechanism is constructed, including the following steps:

[0014] The kinematic calculation model of the four-point supported POGO column parallel mechanism is constructed, including the following steps:

[0015] S101, constructing an initial positive solution kinematic equation;

[0016] S102, substituting the preset posture adjustment parameter data into the initial forward solution kinematic equation to obtain initial workpiece posture data;

[0017] S103, judging whether the initial workpiece posture data is qualified, if so, executing S104, if not, executing S105;

[0018] S104, performing an inverse solution on the initial forward kinematic equation to obtain the kinematic calculation model;

[0019] S105. Correct the initial forward kinematic equation to obtain the corrected initial forward kinematic equation, and return to S102 to execute in a loop until the obtained initial workpiece posture data is qualified, and inversely solve the corrected initial forward kinematic equation that makes the initial workpiece posture data qualified to obtain the kinematic calculation model.

[0020] Furthermore, the workpiece is a cylindrical cabin-section structure, and the workpiece posture includes a pitch angle, a roll angle and a yaw adjustment angle; wherein the pitch angle is the angle of rotation of the axial center line of the workpiece around the X-axis of the system coordinate system, the roll angle is the angle of rotation of the axial center line of the workpiece around the Z-axis of the system coordinate system, and the yaw adjustment angle is the angle of rotation of the axial center line of the workpiece around the Y-axis of the system coordinate system; the Y-axis of the system coordinate system is the vertical direction, the X-axis of the system coordinate system is the longitudinal direction of the horizontal direction, and the Z-axis of the system coordinate system is the transverse direction of the horizontal direction.

[0021] Further, the four-point support POGO column parallel mechanism includes a bottom platform and four mutually parallel support columns, the four support columns are vertically arranged, the four support columns are divided into two groups, each group includes two support columns, each support column has only three degrees of freedom, and the three degrees of freedom are all translational degrees of freedom; one end of the four support columns is connected to the bottom platform, and the other ends of the four support columns are respectively connected to the workpiece through a spherical hinge;

[0022] The parallel mechanism adjustment signal is used to adjust the posture of the four-point supporting POGO column parallel mechanism, specifically, the parallel mechanism adjustment signal is used to adjust the coordinate position of each supporting column corresponding to the three degrees of freedom.

[0023] Furthermore, when adjusting each of the support columns at the coordinate position corresponding to the three degrees of freedom, two support columns in the same group are adjusted synchronously.

[0024] Furthermore, the kinematic calculation model includes the following expressions:

[0025] ;

[0026] ;

[0027] ;

[0028] ;

[0029] ;

[0030] ;

[0031] in, , represents the movement vector of the two support columns in one group being synchronously adjusted in the X-axis direction of the system coordinate system, represents the movement vector of the two support columns in one group being synchronously adjusted in the Y-axis direction of the system coordinate system, A movement vector representing synchronous adjustment of the two support columns in one group in the Z-axis direction of the system coordinate system; represents the movement vector of the two support columns in another group being synchronously adjusted in the X-axis direction of the system coordinate system, represents the movement vector of the two support columns in another group being synchronously adjusted in the Y-axis direction of the system coordinate system, A moving vector representing the synchronous adjustment of the two support columns in the other group in the Z-axis direction of the system coordinate system; represents the pitch angle, represents the roll angle, represents the yaw adjustment angle, represents the spacing between the attitude adjustment units of the four-point support POGO column parallel mechanism when adjusting the pitch angle, Indicates the distance between the axis of the workpiece and the bottom platform surface, represents the spacing between the attitude adjustment units of the four-point support POGO column parallel mechanism when adjusting the roll angle, represents the length of the workpiece, Indicates the diameter of the workpiece.

[0032] Further, the workpiece posture data includes pitch angle data, roll angle data and yaw adjustment angle data;

[0033] Confirming the workpiece posture that needs to be adjusted for the workpiece, and generating workpiece posture data according to the workpiece posture, including the following steps:

[0034] Collecting the position and posture of the workpiece;

[0035] Calculate the difference between the posture of the workpiece and the preset posture, and obtain the values ​​of the pitch angle, roll angle and yaw adjustment angle;

[0036] The pitch angle data, the roll angle data and the yaw adjustment angle data are generated according to the values ​​of the pitch angle, the roll angle and the yaw adjustment angle respectively.

[0037] Further, generating a parallel mechanism adjustment signal according to the posture adjustment parameter data comprises the following steps:

[0038] generating an initial adjustment signal according to the posture adjustment parameter data;

[0039] Generate a posture compensation signal according to the actual posture data of all the support columns; wherein the actual posture data is obtained by respectively collecting the moving position or moving distance of each support column in the coordinate direction of the three degrees of freedom through a grating ruler;

[0040] The parallel mechanism adjustment signal is generated according to the initial adjustment signal and the posture compensation signal.

[0041] Further, generating the parallel mechanism adjustment signal according to the initial adjustment signal and the posture compensation signal comprises the following steps:

[0042] Generate a position adjustment signal according to the initial adjustment signal and the posture compensation signal;

[0043] generating a speed compensation signal according to the movement speed of each of the support columns;

[0044] Generate a current compensation signal according to a control current; wherein the control current is the current of a servo motor that controls the movement of the support column;

[0045] The parallel mechanism adjustment signal is generated according to the position adjustment signal, the speed compensation signal and the current compensation signal.

[0046] In order to solve the above technical problems, the present invention also provides a motion control system of a four-point support POGO column parallel mechanism, and its specific technical contents are as follows:

[0047] A motion control system for a four-point supported POGO column parallel mechanism, comprising:

[0048] A model building module, used to build a kinematic calculation model of a four-point supported POGO column parallel mechanism; wherein the four-point supported POGO column parallel mechanism is used to adjust the posture of the workpiece;

[0049] A data processing module is used to confirm the workpiece posture that needs to be adjusted for the workpiece, and to generate workpiece posture data according to the workpiece posture;

[0050] A calculation module, which substitutes the workpiece posture data into the kinematic calculation model to obtain posture adjustment parameter data;

[0051] A signal conversion module generates a parallel mechanism adjustment signal according to the posture adjustment parameter data;

[0052] The adjustment control module uses the parallel mechanism adjustment signal to adjust the posture of the four-point support POGO column parallel mechanism. BRIEF DESCRIPTION OF THE DRAWINGS

[0053] Figure 1 A flowchart of a motion control method for a four-point supported POGO column parallel mechanism implemented in the present invention;

[0054] Figure 2 This is a simplified structural diagram of a four-point support POGO column parallel mechanism in an embodiment of the present invention;

[0055] Figure 3 Schematic diagram of the workpiece rotating around the Z axis in an embodiment of the present invention;

[0056] Figure 4 Schematic diagram of the workpiece rotating around the X-axis for posture adjustment in an embodiment of the present invention;

[0057] Figure 5 Schematic diagram of the workpiece rotating around the Y-axis for posture adjustment in an embodiment of the present invention;

[0058] Figure 6It is a structural schematic diagram of a motion control system of a four-point support POGO column parallel mechanism in an embodiment of the present invention;

[0059] Figure 7 Schematic diagram of the control principle of the servo control system for controlling the motion of the four-point supported POGO column parallel mechanism in an embodiment of the present invention. DETAILED DESCRIPTION

[0060] The principles and features of the present invention are described below in conjunction with the accompanying drawings. The examples given are only used to explain the present invention and are not used to limit the scope of the present invention.

[0061] like Figure 1 As shown, this embodiment provides a motion control method for a four-point support POGO column parallel mechanism, comprising the following steps:

[0062] S1. Constructing a kinematic calculation model of a four-point supported POGO column parallel mechanism; wherein the four-point supported POGO column parallel mechanism is used to adjust the posture of a workpiece;

[0063] The kinematic calculation model of the four-point supported POGO column parallel mechanism is constructed, including the following steps:

[0064] The kinematic calculation model of the four-point supported POGO column parallel mechanism is constructed, including the following steps:

[0065] S101, constructing an initial positive solution kinematic equation;

[0066] S102, substituting the preset posture adjustment parameter data into the initial forward solution kinematic equation to obtain initial workpiece posture data;

[0067] S103, determine whether the initial workpiece posture data is qualified, if so, execute S104, if not, execute S105; wherein, determining whether the initial workpiece posture data is qualified is specifically: detecting the measured posture data of the workpiece by a detection instrument, comparing the initial workpiece posture data with the measured posture data, if the difference between the initial workpiece posture data and the measured posture data is within a preset range value, then the initial workpiece posture data is determined to be qualified; if the difference between the initial workpiece posture data and the measured posture data is outside the preset range value, then the initial workpiece posture data is determined to be unqualified.

[0068] S104, performing an inverse solution on the initial forward kinematic equation to obtain the kinematic calculation model;

[0069] S105. Correct the initial forward kinematic equation to obtain the corrected initial forward kinematic equation, and return to S102 to execute in a loop until the obtained initial workpiece posture data is qualified, and inversely solve the corrected initial forward kinematic equation that makes the initial workpiece posture data qualified to obtain the kinematic calculation model.

[0070] Specifically, the workpiece is a cylindrical cabin-type structural part, and the workpiece posture includes a pitch angle, a roll angle, and a yaw adjustment angle; wherein the pitch angle The roll angle is the angle at which the axial centerline of the workpiece rotates around the X-axis of the system coordinate system. is the angle of rotation of the axial centerline of the workpiece around the Z axis of the system coordinate system, and the yaw adjustment angle It is the angle of rotation of the axial center line of the workpiece around the Y-axis of the system coordinate system; the Y-axis of the system coordinate system is the vertical direction, the X-axis of the system coordinate system is the longitudinal direction of the horizontal direction, and the Z-axis of the system coordinate system is the transverse direction of the horizontal direction.

[0071] like Figure 2 As shown in the figure, the four-point support POGO column parallel mechanism adopts the support form of n-ppps parallel mechanism, where n=4 represents the number of motion branches, p represents the moving pair, and s represents the spherical pair. The spherical pair connects the motion branch with the motion platform, and the three moving pairs are respectively along the X-axis, Y-axis and Z-axis directions. Therefore, according to the calculation formula of the degree of freedom of the spatial mechanism, it can be obtained that the four-point support POGO column parallel mechanism is a six-degree-of-freedom parallel mechanism, and the four motion branches are distributed in a rectangular or parallel deformation distribution, and a total of 12 drive mechanisms are included.

[0072] Specifically, the four-point support POGO column parallel mechanism includes a bottom platform and four mutually parallel support columns, the four support columns are vertically arranged, the four support columns are divided into two groups, each group includes two support columns, each support column has only three degrees of freedom, and the three degrees of freedom are all translational degrees of freedom; one end of the four support columns is connected to the bottom platform, and the other ends of the four support columns are respectively connected to the workpiece through a spherical hinge;

[0073] The parallel mechanism adjustment signal is used to adjust the posture of the four-point support POGO column parallel mechanism, specifically, the parallel mechanism adjustment signal is used to adjust the coordinate position of each support column corresponding to the three degrees of freedom. When adjusting the coordinate position of each support column corresponding to the three degrees of freedom, two support columns in the same group are adjusted synchronously.

[0074] According to the structural characteristics of the four-point supported POGO column parallel mechanism, the forward and inverse kinematics analysis of the parallel mechanism is carried out:

[0075] The posture of the parallel mechanism in space is represented by the cosine value of the angle between the axes of the system coordinate system C under the same initial coordinates. The rotation matrix for:

[0076] ;

[0077] in, , , They respectively represent the unit vectors of the coordinate axes X1Y1Z1 in the system coordinate system C after the posture adjustment is completed.

[0078] The composite coordinate transformation is a combination of translation coordinate transformation and rotation coordinate transformation. That is, after the posture adjustment is completed, any coordinate B and any point can be transformed by rotation. and translation transformations Convert to the system coordinate system C. The formula for composite coordinate transformation is:

[0079] ;

[0080] Extended to the case where the number of motion branches n=4, that is, the composite adjustment transformation formula of 4 support columns is expressed by the homogeneous transformation matrix:

[0081] ;

[0082] Euler angle is to rotate the system coordinate system three times to obtain the geometric coordinate system representing the workpiece posture. The rotation matrix is ​​calculated with three rotation angles as three independent quantities. The rotation method is to rotate around the Z axis first. Angle, get X1Y1Z1, and then rotate around X1 Angle, get X2Y2Z2, and then rotate around Z2 Angle, get the geometric coordinate system X3Y3Z3. The three rotation processes are independent of each other, and the rotation matrix can be calculated from the values ​​of the three rotation angles:

[0083] ;

[0084] ;

[0085] in, Indicates the rotation angle around the Z axis , Indicates the rotation angle around the X axis , Refers to the Z axis after rotation ( ) Direction rotation angle .

[0086] The kinematic equations corresponding to the parallel mechanism's adjustment process are established and solved piecewise in sequence.

[0087] The transformation relationship between the parallel mechanism posture before posture adjustment and the target space posture is known, that is, the rotation matrix of the known geometric coordinate system relative to the reference coordinate system and translation matrix , the kinematic equations can be decomposed in piecewise form to obtain the rotation angles that keep the center of gravity unchanged. Analytical solution.

[0088] like Figure 3 As shown in the figure, the cabin section rotation adjustment around the Z axis, that is, the pitch angle adjustment expression is:

[0089] , ;

[0090] in, , They are the displacement of the center axis of the adjustment mechanism along the X and Y directions when the center axis position of the adjusted compartment remains unchanged. To adjust the height of the cabin section from the center of the plane of the attitude adjustment mechanism.

[0091] , ;

[0092] in, , They are respectively the displacement of the center position along the X and Y directions caused by multi-point support before and after adjustment when the center axis position of the adjusted cabin section remains unchanged, It is the distance between the posture adjustment units of the posture adjustment mechanism.

[0093] When the cabin needs to adjust its pitch attitude around the Z axis, in order to ensure that the position of the cabin center axis remains unchanged after adjustment, the adjustment amounts of the X-direction lateral displacement and Y-direction lateral displacement corresponding to the left and right adjustment mechanisms are respectively , , and The left and right adjustment mechanisms respectively represent the above-mentioned one group of support columns and the other group of support columns.

[0094] ;

[0095] ;

[0096] ;

[0097] ;

[0098] in, Adjust the angle for the pitch angle.

[0099] by As an example, by substituting into the above formula, the corresponding displacement in the X direction and the Y direction can be obtained respectively.

[0100] ;

[0101] ;

[0102] ;

[0103] ;

[0104] That is, when the pitch angle adjustment amount is 5°, the displacement of the attitude adjustment mechanism in the X direction on one side is 36.65mm, and the displacement of the corresponding side in the X direction is 33.07mm; the lifting displacement of the attitude adjustment mechanism in the Y direction is -39.44mm (reverse), and the lifting displacement of the corresponding side in the Y direction is 42.49mm.

[0105] like Figure 4 As shown, the cabin section rotates around the X-axis to adjust the attitude, that is, the roll angle adjustment expression is:

[0106] , ;

[0107] in, , They are the displacement of the center axis of the adjustment mechanism in the Z and Y directions when the center axis position of the adjusted compartment, i.e. the workpiece, remains unchanged. To adjust the height of the cabin section from the center of the plane of the attitude adjustment mechanism.

[0108] , ;

[0109] in, , They are the displacement of the center position along the Z and Y directions caused by the distributed attitude adjustment mechanism before and after the adjustment when the center axis position of the adjusted cabin section remains unchanged, It is the distance between the posture adjustment units of the posture adjustment mechanism.

[0110] When the cabin needs to adjust its rolling attitude around the X axis, in order to ensure that the position of the cabin center axis remains unchanged after adjustment, the adjustment amounts of the Z-direction lateral movement and Y-direction lifting and lowering corresponding to the adjustment mechanisms on the left and right sides are respectively , , and .

[0111] ;

[0112] ;

[0113] ;

[0114] ;

[0115] in, Adjust the angle for the roll angle. As an example, by substituting into the above formula, the corresponding displacement in the Z direction and the Y direction can be obtained respectively.

[0116] ;

[0117] ;

[0118] ;

[0119] ;

[0120] That is, when the roll angle adjustment amount is 8°, the displacement of one side of the attitude adjustment mechanism, i.e. one group of support columns, in the Z direction is 60.05mm, and the displacement of the corresponding side, i.e. the other group of support columns, in the Z direction is -51.29mm (51.29mm moved in the opposite direction along the Z axis); the lifting and lowering displacement of one group of support columns of the attitude adjustment mechanism in the Y direction is -58.74mm (58.74mm moved in the opposite direction along the Y axis), and the lifting and lowering displacement of the corresponding side, i.e. the other group of support columns, in the Y direction is 66.52mm.

[0121] like Figure 5 As shown, the cabin section rotates around the Y axis to adjust the attitude, that is, the yaw angle adjustment expression is:

[0122] , ;

[0123] in, , are the length and diameter of the cabin to be adjusted respectively. When the cabin needs to adjust its yaw attitude around the Y axis, in order to ensure that the position of the cabin center axis remains unchanged after adjustment, the adjustment amounts of the Z-direction lateral movement and X-direction lifting of the left and right adjustment mechanisms, i.e., the two sets of support columns mentioned above, are respectively , , and .

[0124] ;

[0125] ;

[0126] ;

[0127] ;

[0128] in, Adjust the angle for the yaw angle. As an example, by substituting into the above formula, the corresponding displacement in the Z direction and the X direction can be obtained respectively.

[0129] ;

[0130] ;

[0131] ;

[0132] ;

[0133] That is, when the yaw angle adjustment amount is 5°, the single-side Z-direction displacement of the attitude adjustment unit is 24.24mm, and the corresponding side Z-direction displacement is -26.05mm (reverse); the X-direction displacement of the attitude adjustment unit is 44.72mm, and the corresponding side X-direction lifting displacement is -42.44mm (reverse).

[0134] The kinematic calculation model finally obtained includes the following expressions:

[0135] ;

[0136] ;

[0137] ;

[0138] ;

[0139] ;

[0140] ;

[0141] in, , represents the movement vector of the two support columns in one group being synchronously adjusted in the x-axis direction of the system coordinate system, represents the movement vector of the two support columns in one group being synchronously adjusted in the Y-axis direction of the system coordinate system, A movement vector representing synchronous adjustment of the two support columns in one group in the Z-axis direction of the system coordinate system; represents the movement vector of the two support columns in another group being synchronously adjusted in the X-axis direction of the system coordinate system, represents the movement vector of the two support columns in another group being synchronously adjusted in the Y-axis direction of the system coordinate system, A moving vector representing the synchronous adjustment of the two support columns in the other group in the Z-axis direction of the system coordinate system; represents the pitch angle, represents the roll angle, represents the yaw adjustment angle, represents the spacing between the attitude adjustment units of the four-point support POGO column parallel mechanism when adjusting the pitch angle, Indicates the distance between the axis of the workpiece and the bottom platform surface, represents the spacing between the attitude adjustment units of the four-point support POGO column parallel mechanism when adjusting the roll angle, represents the length of the workpiece, Indicates the diameter of the workpiece.

[0142] S2, confirming the workpiece posture that needs to be adjusted for the workpiece, and generating workpiece posture data according to the workpiece posture; the workpiece posture data includes pitch angle data, roll angle data and yaw adjustment angle data;

[0143] Confirming the workpiece posture that needs to be adjusted for the workpiece, and generating workpiece posture data according to the workpiece posture, including the following steps:

[0144] Collecting the position and posture of the workpiece;

[0145] Calculate the difference between the posture of the workpiece and the preset posture, and obtain the values ​​of the pitch angle, roll angle and yaw adjustment angle;

[0146] The pitch angle data, the roll angle data and the yaw adjustment angle data are generated according to the values ​​of the pitch angle, the roll angle and the yaw adjustment angle respectively.

[0147] S3, substituting the workpiece posture data into the kinematic calculation model to obtain posture adjustment parameter data;

[0148] S4, generating a parallel mechanism adjustment signal according to the posture adjustment parameter data;

[0149] Generating a parallel mechanism adjustment signal according to the posture adjustment parameter data comprises the following steps:

[0150] S401, generating an initial adjustment signal according to the posture adjustment parameter data;

[0151] S402, generating a posture compensation signal according to the actual posture data of all the support columns; wherein the actual posture data is obtained by respectively collecting the moving position or moving distance of each support column in the coordinate direction of the three degrees of freedom through a grating ruler;

[0152] S403, generating the parallel mechanism adjustment signal according to the initial adjustment signal and the posture compensation signal.

[0153] Generating the parallel mechanism adjustment signal according to the initial adjustment signal and the posture compensation signal comprises the following steps:

[0154] Generate a position adjustment signal according to the initial adjustment signal and the posture compensation signal;

[0155] generating a speed compensation signal according to the movement speed of each of the support columns;

[0156] Generate a current compensation signal according to a control current; wherein the control current is the current of a servo motor that controls the movement of the support column;

[0157] The parallel mechanism adjustment signal is generated according to the position adjustment signal, the speed compensation signal and the current compensation signal.

[0158] S5. Utilize the parallel mechanism adjustment signal to adjust the posture of the four-point support POGO column parallel mechanism.

[0159] The embodiment of the present invention adopts the forward and inverse solution method of the four-point support axis linkage algorithm, and builds a vector space and control method by solving the trigonometric function relationship through three groups of eight-axis linkage, realizes the coupling superposition of the angle and position forward solutions, and obtains the inverse solution result of the axis position relationship through the breadth-first method, and the maximum angle coupling solution time is less than 300ms; the multi-axis linkage precision motion control method is based on the grating scale closed-loop feedback servo motor motion control system, and is integrated to form a multi-axis position tracking control strategy, and the adjustment accuracy can reach ±0.005mm.

[0160] like Figure 6 As shown, in some other embodiments, a motion control system of a four-point support POGO column parallel mechanism is also provided, comprising:

[0161] A model building module, used to build a kinematic calculation model of a four-point supported POGO column parallel mechanism; wherein the four-point supported POGO column parallel mechanism is used to adjust the posture of the workpiece;

[0162] A data processing module is used to confirm the workpiece posture that needs to be adjusted for the workpiece, and to generate workpiece posture data according to the workpiece posture;

[0163] A calculation module, which substitutes the workpiece posture data into the kinematic calculation model to obtain posture adjustment parameter data;

[0164] A signal conversion module generates a parallel mechanism adjustment signal according to the posture adjustment parameter data;

[0165] The adjustment control module uses the parallel mechanism adjustment signal to adjust the posture of the four-point support POGO column parallel mechanism.

[0166] like Figure 7 As shown, in some embodiments, a servo control system is also provided, which is used to control the four-point support POGO column parallel mechanism to adjust the posture and movement, and includes an information and data processing module, a signal conversion module and an adjustment control module:

[0167] The information and data processing module includes the above-mentioned model building module, data processing module, calculation module and:

[0168] The signal conversion module includes:

[0169] A current loop controller is used to generate a current compensation signal based on a control current; wherein the control current is the current of a servo motor that controls the movement of the support column; the input of the current loop controller integrates the current command and the feedback signal, so that the current in the armature winding is effectively controlled in both amplitude and phase, completing orthogonal or weak magnetic high-speed control with the flux vector; the current controller usually adopts a proportional-integral control law, which is fast enough to meet the requirements for tracking and controlling the instantaneous value of the current.

[0170] The speed loop controller is used to generate a speed compensation signal according to the movement speed of each support column; the speed controller in the speed loop controller also adopts a control law, and its output is used as a given quantity of the current controller, and is limited within a certain amplitude to limit the current value of the maximum armature circuit. The function of the speed controller is mainly to be able to perform stable speed control so that it does not oscillate during positioning; in position control, the speed loop is required to have the ability to quickly respond to speed instructions and have good characteristic hardness in steady state to suppress speed fluctuations.

[0171] The position loop controller is used to generate a position adjustment signal according to the initial adjustment signal and the posture compensation signal; the position sensor element in the position loop controller transmits the real-time displacement signal of the motion mechanism to the control device for position control, which is used to ensure the static accuracy and dynamic tracking performance of the system. The task of the position servo system is to enable the actuator to accurately track the position instruction. The proportional-differential control law can suppress oscillation, reduce overshoot, enhance stability, and speed up the tracking speed of the system.

[0172] The adjustment control module is specifically a servo system, which is used to generate the parallel mechanism adjustment signal according to the position adjustment signal, the speed compensation signal and the current compensation signal, wherein the parallel mechanism adjustment signal is then processed and amplified by a three-week angle converter and a signal amplifier to obtain a feedback control signal, and the feedback control signal includes the servo control data of each support column. The information and data processing module calculates the position and posture of each support column according to the servo control data, thereby realizing feedback control of each support column.

[0173] The embodiment of the present invention adopts the support form of n-ppps parallel mechanism by designing the attitude adjustment system, in which the spherical pair connects the motion branch and the motion platform, and the three moving pairs are respectively along the X-axis, Y-axis and Z-axis directions. During the attitude adjustment process, the present invention establishes corresponding kinematic equations for the adjustment process of each direction of the mechanism, and solves them piecewise in sequence, thereby achieving full decoupling of the position control of the axis system adjustment, ensuring that the position of the center point of the rotary axis remains unchanged during the single-axis movement, and does not affect the attitude adjustment of the cabin section around other axis systems and the position adjustment of the overall translation and lifting.

[0174] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the concept and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A motion control method for a four-point supported POGO column parallel mechanism, characterized in that: The steps include: Constructing a kinematic calculation model of a four-point supported POGO column parallel mechanism; wherein the four-point supported POGO column parallel mechanism is used to adjust the posture of a workpiece; Confirming the workpiece posture that needs to be adjusted for the workpiece, and generating workpiece posture data according to the workpiece posture; Substituting the workpiece posture data into the kinematic calculation model to obtain posture adjustment parameter data; Generate a parallel mechanism adjustment signal according to the posture adjustment parameter data; Using the parallel mechanism adjustment signal to adjust the posture of the four-point support POGO column parallel mechanism; The workpiece is a cylindrical cabin-type structural part, and the workpiece posture includes a pitch angle, a roll angle, and a yaw adjustment angle; wherein the pitch angle is the angle at which the axial center line of the workpiece rotates around the x-axis of the system coordinate system, and the roll angle is The yaw adjustment angle is the angle at which the axial centerline of the workpiece rotates around the Z axis of the system coordinate system. The yaw adjustment angle is the angle at which the axial centerline of the workpiece rotates around the Y axis of the system coordinate system. The Y axis of the system coordinate system is the vertical direction, the X axis of the system coordinate system is the longitudinal direction of the horizontal direction, and the Z axis of the system coordinate system is the transverse direction of the horizontal direction. The four-point support POGO column parallel mechanism includes a bottom platform and four mutually parallel support columns, the four support columns are vertically arranged, the four support columns are divided into two groups, each group includes two support columns, each support column has only three degrees of freedom, and the three degrees of freedom are all translational degrees of freedom; one end of the four support columns is connected to the bottom platform, and the other ends of the four support columns are respectively connected to the workpiece through a spherical hinge; Using the parallel mechanism adjustment signal to adjust the posture of the four-point support POGO column parallel mechanism, specifically using the parallel mechanism adjustment signal to adjust the coordinate position of each support column corresponding to the three degrees of freedom; The kinematic calculation model includes the following expressions: ； ； ； ； ； ； in, , represents the movement vector of the two support columns in one group being synchronously adjusted in the x-axis direction of the system coordinate system, represents the movement vector of the two support columns in one group being synchronously adjusted in the Y-axis direction of the system coordinate system, A movement vector representing synchronous adjustment of the two support columns in one group in the Z-axis direction of the system coordinate system; represents the movement vector of the two support columns in another group being synchronously adjusted in the X-axis direction of the system coordinate system, represents the movement vector of the two support columns in another group being synchronously adjusted in the Y-axis direction of the system coordinate system, A moving vector representing the synchronous adjustment of the two support columns in the other group in the Z-axis direction of the system coordinate system; represents the pitch angle, represents the roll angle, represents the yaw adjustment angle, represents the spacing between the attitude adjustment units of the four-point support POGO column parallel mechanism when adjusting the pitch angle, Indicates the distance between the axis of the workpiece and the bottom platform surface, represents the spacing between the attitude adjustment units of the four-point support POGO column parallel mechanism when adjusting the roll angle, represents the length of the workpiece, represents the diameter of the workpiece; The workpiece posture data includes pitch angle data, roll angle data and yaw adjustment angle data; Confirming the workpiece posture that needs to be adjusted for the workpiece, and generating workpiece posture data according to the workpiece posture, including the following steps: Collecting the position and posture of the workpiece; Calculate the difference between the posture of the workpiece and the preset posture, and obtain the values ​​of the pitch angle, roll angle and yaw adjustment angle; The pitch angle data, the roll angle data and the yaw adjustment angle data are generated according to the values ​​of the pitch angle, the roll angle and the yaw adjustment angle respectively.

2. The motion control method of the four-point support POGO column parallel mechanism according to claim 1 is characterized in that: The kinematic calculation model of the four-point supported POGO column parallel mechanism is constructed, including the following steps: S101, constructing the initial positive solution kinematic equation; S102, substituting the preset posture adjustment parameter data into the initial forward solution kinematic equation to obtain initial workpiece posture data; S103, judging whether the initial workpiece posture data is qualified, if so, executing S104, if not, executing S105; S104, performing an inverse solution on the initial forward kinematic equation to obtain the kinematic calculation model; S105. Correct the initial forward kinematic equation to obtain the corrected initial forward kinematic equation, and return to S102 to execute in a loop until the obtained initial workpiece posture data is qualified, and inversely solve the corrected initial forward kinematic equation that makes the initial workpiece posture data qualified to obtain the kinematic calculation model.

3. The motion control method of the four-point support POGO column parallel mechanism according to claim 2 is characterized in that: When adjusting each of the support columns at the coordinate position corresponding to the three degrees of freedom, two support columns in the same group are adjusted synchronously.

4. The motion control method of the four-point support POGO column parallel mechanism according to claim 3 is characterized in that: Generating a parallel mechanism adjustment signal according to the posture adjustment parameter data comprises the following steps: generating an initial adjustment signal according to the posture adjustment parameter data; Generate a posture compensation signal according to the actual posture data of all the support columns; wherein the actual posture data is obtained by respectively collecting the moving position or moving distance of each support column in the coordinate direction of the three degrees of freedom through a grating ruler; The parallel mechanism adjustment signal is generated according to the initial adjustment signal and the posture compensation signal.

5. The motion control method of the four-point support POGO column parallel mechanism according to claim 4 is characterized in that: Generating the parallel mechanism adjustment signal according to the initial adjustment signal and the posture compensation signal comprises the following steps: Generate a position adjustment signal according to the initial adjustment signal and the posture compensation signal; generating a speed compensation signal according to the movement speed of each of the support columns; Generate a current compensation signal according to a control current; wherein the control current is the current of a servo motor that controls the movement of the support column; The parallel mechanism adjustment signal is generated according to the position adjustment signal, the speed compensation signal and the current compensation signal.

6. A motion control system for a four-point supported POGO column parallel mechanism, characterized in that: include: A model building module, used to build a kinematic calculation model of a four-point supported POGO column parallel mechanism; wherein the four-point supported POGO column parallel mechanism is used to adjust the posture of the workpiece; A data processing module is used to confirm the workpiece posture that needs to be adjusted for the workpiece, and to generate workpiece posture data according to the workpiece posture; A calculation module, which substitutes the workpiece posture data into the kinematic calculation model to obtain posture adjustment parameter data; A signal conversion module generates a parallel mechanism adjustment signal according to the posture adjustment parameter data; An adjustment control module, which uses the parallel mechanism adjustment signal to adjust the posture of the four-point support POGO column parallel mechanism; The workpiece is a cylindrical cabin-type structural part, and the workpiece posture includes a pitch angle, a roll angle, and a yaw adjustment angle; wherein the pitch angle is the angle at which the axial center line of the workpiece rotates around the x-axis of the system coordinate system, and the roll angle is The yaw adjustment angle is the angle at which the axial centerline of the workpiece rotates around the Z axis of the system coordinate system. The yaw adjustment angle is the angle at which the axial centerline of the workpiece rotates around the Y axis of the system coordinate system. The Y axis of the system coordinate system is the vertical direction, the X axis of the system coordinate system is the longitudinal direction of the horizontal direction, and the Z axis of the system coordinate system is the transverse direction of the horizontal direction. The four-point support POGO column parallel mechanism includes a bottom platform and four mutually parallel support columns, the four support columns are vertically arranged, the four support columns are divided into two groups, each group includes two support columns, each support column has only three degrees of freedom, and the three degrees of freedom are all translational degrees of freedom; one end of the four support columns is connected to the bottom platform, and the other ends of the four support columns are respectively connected to the workpiece through a spherical hinge; Using the parallel mechanism adjustment signal to adjust the posture of the four-point support POGO column parallel mechanism, specifically using the parallel mechanism adjustment signal to adjust the coordinate position of each support column corresponding to the three degrees of freedom; The kinematic calculation model includes the following expressions: ； ； ； ； ； ； in, , represents the movement vector of the two support columns in one group being synchronously adjusted in the x-axis direction of the system coordinate system, represents the movement vector of the two support columns in one group being synchronously adjusted in the Y-axis direction of the system coordinate system, A movement vector representing synchronous adjustment of the two support columns in one group in the Z-axis direction of the system coordinate system; represents the movement vector of the two support columns in another group being synchronously adjusted in the X-axis direction of the system coordinate system, represents the movement vector of the two support columns in another group being synchronously adjusted in the Y-axis direction of the system coordinate system, A moving vector representing the synchronous adjustment of the two support columns in the other group in the Z-axis direction of the system coordinate system; represents the pitch angle, represents the roll angle, represents the yaw adjustment angle, represents the spacing between the attitude adjustment units of the four-point support POGO column parallel mechanism when adjusting the pitch angle, Indicates the distance between the axis of the workpiece and the bottom platform surface, represents the spacing between the attitude adjustment units of the four-point support POGO column parallel mechanism when adjusting the roll angle, represents the length of the workpiece, represents the diameter of the workpiece; The workpiece posture data includes pitch angle data, roll angle data and yaw adjustment angle data; Confirming the workpiece posture that needs to be adjusted for the workpiece, and generating workpiece posture data according to the workpiece posture, including the following steps: Collecting the position and posture of the workpiece; Calculate the difference between the posture of the workpiece and the preset posture, and obtain the values ​​of the pitch angle, roll angle and yaw adjustment angle; The pitch angle data, the roll angle data and the yaw adjustment angle data are generated according to the values ​​of the pitch angle, the roll angle and the yaw adjustment angle respectively.

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