Multi-axis parallel platform positioning method and device without feedback control

Abstract

The invention belongs to the technical field of multi-axis parallel platform positioning, and particularly discloses a multi-axis parallel platform positioning method and device without feedback control. The method comprises the following steps: modeling a system error of a multi-axis parallel platform into an assembly error, a processing error and a reverse idle stroke error of each actuator in the multi-axis parallel platform, and compensating a current joint vector of each actuator to obtain a compensated joint vector of each actuator; the assembly error and the machining error are obtained by resolving full-degree-of-freedom stepping test data of the multi-axis parallel platform; the reverse idle stroke error of each actuator is obtained by performing motion test analysis on each actuator; and adjusting the action of each actuator according to the compensated joint vector of each actuator so as to position the pose of the multi-axis parallel platform. According to the multi-axis parallel platform, the positioning precision of the multi-axis parallel platform can be effectively improved, and the multi-axis parallel platform can be suitable for more stringent high-precision application scenes.

Description

Technical Field

[0001] The present application belongs to the technical field of multi-axis parallel platform positioning, and more specifically, relates to a multi-axis parallel platform positioning method and device without feedback control. Background Art

[0002] The precise adjustment of the position and attitude of detectors such as CMOS and CCD in the microscopic imaging optical path relies on a full-degree-of-freedom multi-axis parallel platform positioning device. The parallel mechanism in this device is widely used for the precise adjustment of the position and attitude of detectors due to its advantages such as high rigidity, high precision, and large load capacity. However, the existing multi-axis parallel platform faces important technical challenges when applied to high-precision application scenarios such as optical imaging systems. In practical applications, the compact layout of the microscopic imaging optical path limits the installation space of the parallel positioning platform. Due to spatial constraints, it is often difficult to integrate a position feedback device into the parallel mechanism for closed-loop control, resulting in the actual motion trajectory of the parallel mechanism often deviating from the theoretical design trajectory and low positioning accuracy.

[0003] Conventional feedback-free control methods for multi-axis parallel platforms typically rely on a pre-defined idealized kinematic model and precise motor drive commands to achieve the target position of the end effector. These control processes do not rely on real-time feedback. However, the positioning accuracy of this feedback-free control approach is inherently limited by factors such as the accuracy of the kinematic model (including geometric parameter errors, nonlinear errors, coupling errors, etc.), the inherent precision and consistency of the drive components, the manufacturing and assembly errors of the transmission mechanism (clearance, backlash, elastic deformation), and structural deformation caused by load or dynamic motion. This results in significant cumulative errors in the positioning process from command to actual position that are difficult to compensate in real time, making it difficult to meet high-precision requirements.

[0004] Therefore, how to better achieve the positioning of multi-axis parallel platforms without feedback control has become a technical problem that needs to be solved urgently in the industry. Summary of the Invention

[0005] In response to the defects of the existing technology, the purpose of this application is to better realize the positioning of the multi-axis parallel platform, aiming to solve the problem that the traditional multi-axis parallel platform positioning method based on feedback-free control will produce significant and difficult to compensate for cumulative errors in the positioning process from instructions to actual posture, making it difficult to meet high-precision requirements.

[0006] To achieve the above objectives, in a first aspect, the present application provides a multi-axis parallel platform positioning method without feedback control, comprising: The system error of the multi-axis parallel platform is modeled as an assembly error, a machining error, and a reverse lost motion error of each actuator in the multi-axis parallel platform, and the current joint vector of each actuator is compensated to obtain a compensated joint vector of each actuator; the assembly error and the machining error are obtained by solving the full-degree-of-freedom step test data of the multi-axis parallel platform; and the reverse lost motion error of each actuator is obtained by performing motion test analysis on each actuator; The action of each actuator is adjusted according to the compensated joint vector of each actuator to position the posture of the multi-axis parallel platform.

[0007] Optionally, before modeling the system error of the multi-axis parallel platform as assembly error, machining error, and reverse backlash error of each actuator in the multi-axis parallel platform, and compensating the current joint vector of each actuator to obtain the compensated joint vector of each actuator, the method further includes: For any of the actuators, obtaining an actual forward displacement increment when the actuator moves forward to a position where the thread lost motion is zero, and obtaining an actual reverse displacement increment when the actuator moves reversely from a position where the thread lost motion is zero to a stop; Based on the actual positive displacement increment and the actual reverse displacement increment corresponding to each of the actuators, a reverse lost motion error of each of the actuators during motion steering is determined.

[0008] Optionally, the step of acquiring full-degree-of-freedom stepping test data of the multi-axis parallel platform specifically includes: Determine the calibration stroke of the multi-axis parallel platform in each degree of freedom, and divide the calibration stroke in each degree of freedom into equal parts, and determine each measurement point in each degree of freedom and its corresponding theoretical pose of the step test; When the multi-axis parallel platform performs a step test on each degree of freedom, determining an actual posture error of a measurement point corresponding to each step test on each degree of freedom; According to the theoretical posture and actual posture error corresponding to each measurement point on each degree of freedom, step test data on each degree of freedom is obtained; the degrees of freedom include translational degree of freedom and rotational degree of freedom.

[0009] Optionally, the specific steps of solving the full-degree-of-freedom step test data of the multi-axis parallel platform to obtain the assembly error include: Determining a kinematic error transfer equation of an actuator of the multi-axis parallel platform based on an inverse kinematic equation of the multi-axis parallel platform; Determine a linear coefficient between the theoretical pose and the actual pose error for each measurement point on each degree of freedom according to the theoretical pose and the actual pose error corresponding to each measurement point on each degree of freedom; The assembly error is obtained by solving the kinematic error transfer equation and the linear coefficient corresponding to each degree of freedom.

[0010] Optionally, the specific steps of solving the full-degree-of-freedom stepping test data of the multi-axis parallel platform to obtain the machining error include: Determine the theoretical pose error corresponding to each measuring point on each degree of freedom according to the theoretical pose corresponding to each measuring point on each degree of freedom and the linear coefficient between the theoretical pose and the actual pose error on each degree of freedom; Determining a residual corresponding to each measurement point on each degree of freedom according to a theoretical actual posture error and an actual posture error corresponding to each measurement point on each degree of freedom; The machining error is obtained by performing an inverse solution based on the residual corresponding to each measurement point on each degree of freedom and the inverse kinematic equation of the multi-axis parallel platform.

[0011] Optionally, the multi-axis parallel platform is a six-axis parallel positioning platform; The six-axis parallel positioning platform includes a base, a six-axis linkage mechanism fixed above the base, and a moving platform arranged above the six-axis linkage mechanism; The six-axis linkage mechanism includes three fixed slots, each of which is provided with a ball slot mechanism and two actuator mounting positions, wherein each of the actuator mounting positions is provided with an actuator; Each of the ball-slot mechanisms comprises a metal ball, an inclined slot, and a guide rail; the metal ball is located in the inclined slot; and the top end of each metal ball is connected to the moving platform; Each of the actuators is used to push the inclined slot to perform linear motion on the guide rail, so that the inclined slot and the metal ball form a kinematic pair through point contact, so as to adjust the posture of the moving platform.

[0012] In a second aspect, the present application provides a multi-axis parallel platform positioning device without feedback control, comprising: a compensation processing module, configured to model the system error of the multi-axis parallel platform as an assembly error, a machining error, and a reverse lost motion error of each actuator in the multi-axis parallel platform, and compensate a current joint vector of each actuator to obtain a compensated joint vector of each actuator; the assembly error and the machining error are obtained by solving full-degree-of-freedom stepping test data of the multi-axis parallel platform; and the reverse lost motion error of each actuator is obtained by performing motion test analysis on each actuator; The posture positioning module is used to adjust the action of each actuator according to the compensated joint vector of each actuator to position the posture of the multi-axis parallel platform.

[0013] In a third aspect, the present application provides an electronic device comprising: at least one memory for storing programs; and at least one processor for executing the programs stored in the memory. When the program stored in the memory is executed, the processor is used to execute the method described in the first aspect or any possible implementation of the first aspect.

[0014] In a fourth aspect, the present application provides a computer-readable storage medium, which stores a computer program. When the computer program runs on a processor, the processor executes the method described in the first aspect or any possible implementation of the first aspect.

[0015] In a fifth aspect, the present application provides a computer program product, which, when executed on a processor, enables the processor to execute the method described in the first aspect or any possible implementation of the first aspect.

[0016] It can be understood that the beneficial effects of the second to fifth aspects mentioned above can be found in the relevant description of the first aspect mentioned above, and will not be repeated here.

[0017] In general, the above technical solutions conceived by this application have the following beneficial effects compared with the existing technologies: The present application provides a multi-axis parallel platform positioning method and device with feedback-free control. The method and device obtain the assembly error, processing error and reverse backlash error of the multi-axis parallel platform by adopting a calibration test technology based on precision measurement, and use these kinematic parameter errors to compensate for the current joint vector of each actuator, and adjust the action of each actuator according to the compensated joint vector of each actuator to position the posture of the multi-axis parallel platform. Compared with the traditional direct feedback-free control method that only uses the initial ideal model, the compensation mechanism with embedded inherent errors of the parallel platform can significantly reduce the influence of systematic error sources caused by model inaccuracy, manufacturing and assembly deviations, etc. on the end positioning accuracy, thereby effectively improving the positioning accuracy of the multi-axis parallel platform, making it suitable for more stringent high-precision application scenarios, while maintaining the inherent advantages of feedback-free control, simple structure, low cost, and no sensor delay. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 1 is a flow chart of a multi-axis parallel platform positioning method without feedback control provided in an embodiment of the present application; Figure 2 Schematic diagram of thread idle stroke of the actuator provided in an embodiment of the present application; Figure 3 Schematic diagram of a displacement measurement system in the direction of motion of an actuator provided in an embodiment of the present application; Figure 4 Schematic diagram of the structure of the six-axis parallel positioning platform provided in an embodiment of the present application; Figure 5 Schematic diagram of the structure of the ball-groove mechanism in the six-axis parallel positioning platform provided in an embodiment of the present application; Figure 6 1 is a schematic structural diagram of a multi-axis parallel platform positioning device without feedback control provided in an embodiment of the present application; Figure 7 It is a structural diagram of an electronic device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0019] In order to make the purpose, technical solutions and advantages of this application more clear, the following further describes this application in detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain this application and are not intended to limit this application.

[0020] In the specification and claims of this application, the terms "first" and "second" are used to distinguish different objects, rather than to describe a specific order of objects. For example, "first response message" and "second response message" are used to distinguish different response messages, rather than to describe a specific order of response messages.

[0021] In the embodiments of this application, words such as "exemplary" or "for example" are used to indicate examples, illustrations, or descriptions. Any embodiment or design described as "exemplary" or "for example" in the embodiments of this application should not be interpreted as being preferred or advantageous over other embodiments or designs. Rather, the use of words such as "exemplary" or "for example" is intended to present the relevant concepts in a concrete manner.

[0022] In the description of the embodiments of the present application, unless otherwise specified, "multiple" means two or more, for example, multiple processing units means two or more processing units, etc.; multiple elements means two or more elements, etc.

[0023] The embodiments of the present application are described below in conjunction with the drawings in the embodiments of the present application.

[0024] Figure 1 is a flow chart of a multi-axis parallel platform positioning method without feedback control provided in an embodiment of the present application. It can be understood that this method can be applied to a multi-axis parallel platform including multiple actuators, such as Figure 1 As shown, the method includes: Step S1: Modeling the system error of the multi-axis parallel platform as assembly error, machining error, and reverse lost motion error of each actuator in the multi-axis parallel platform, compensating the current joint vector of each actuator to obtain a compensated joint vector of each actuator; the assembly error and machining error are obtained by solving the full-degree-of-freedom step test data of the multi-axis parallel platform; the reverse lost motion error of each actuator is obtained by performing motion test analysis on each actuator; Step S2: adjusting the action of each actuator according to the compensated joint vector of each actuator to position the posture of the multi-axis parallel platform.

[0025] Specifically, the assembly error described in the embodiments of this application refers to the deviation between the actual structure of a multi-axis parallel platform and the designed model due to manufacturing errors of components, improper assembly processes, or improper assembly methods during the assembly process. This deviation may affect the kinematic performance and positioning accuracy of the platform.

[0026] The machining errors described in the embodiments of this application refer to the deviations in the actual geometric shapes of related components from their theoretical design shapes caused by various error factors during the manufacturing process of key kinematic pairs. Such errors may affect the machining quality and the positioning accuracy of the platform.

[0027] The reverse backlash error described in the embodiment of the present application refers to the lag in displacement or posture of the output action of the actuator in the multi-axis parallel platform when the input direction changes from forward to reverse in the working state.

[0028] In an embodiment of the present application, in step S1, the system error of the multi-axis parallel platform is modeled as assembly error, machining error, and reverse lost motion error of each actuator in the multi-axis parallel platform. This allows pre-collection of full-degree-of-freedom stepping test data of the multi-axis parallel platform and calculation of the full-degree-of-freedom stepping test data of the multi-axis parallel platform by solving the kinematic equation to obtain the assembly error and machining error. At the same time, by performing forward and reverse motion tests on each actuator in the multi-axis parallel platform, the reverse lost motion error of each actuator can be obtained based on the motion displacement deviation.

[0029] Furthermore, in step S1, the current joint vector of each actuator can be compensated using the assembly error, machining error of the multi-axis parallel platform and the reverse backlash error of each actuator in the multi-axis parallel platform obtained above, thereby obtaining the compensated joint vector of each actuator.

[0030] More specifically, in the embodiment of the present application, the compensated joint vectors of each actuator in the multi-axis parallel platform can be obtained by the following model, namely:

[0031] Where Θ represents the joint vector after actuator compensation; Indicates processing error; Indicates the reverse lost motion error of the actuator; Represents the theoretical pose vector of the multi-axis parallel platform; Indicates assembly error; Express the general inverse kinematic equations of a multi-axis parallel platform; represents the theoretical joint vector of the actuator calculated using the corrected joint structure parameters; Represents the structural parameter vector of the multi-axis parallel platform.

[0032] Furthermore, in step S2, the action of each actuator is adjusted according to the compensated joint vector of each actuator, so that each actuator moves to the desired design position, and the precise adjustment of the posture of the internal parallel mechanism dynamic platform is completed through the linkage mechanism, thereby achieving precise positioning of the multi-axis parallel platform posture.

[0033] In an embodiment of the present application, under a feedback-free control framework, a calibration technology based on precision measurement is used to pre-acquire the actual kinematic parameter errors of the platform, including assembly errors, processing errors, reverse backlash errors of each actuator, and key nonlinear factors. Based on this, the core kinematic equations (especially the inverse kinematic model) are accurately corrected and compensated for. During actual operation, the controller can calculate the drive instructions based on this corrected high-precision kinematic model to control the movement of each actuator.

[0034] In a specific embodiment of the present application, in the application scenario of a microscopic imaging system, detectors such as CMOS or CCD in the microscopic imaging optical path are fixed on a multi-axis parallel platform. By accurately positioning the posture of the multi-axis parallel platform, precise adjustment of the position and posture of each detector is completed. Since there is no need to introduce sensor feedback, the volume of the multi-axis parallel platform will not be increased, and high-precision alignment of multiple imaging focal planes can be achieved in a compact microscopic imaging system at low cost.

[0035] The feedback-free control multi-axis parallel platform positioning method of the embodiment of the present application obtains the assembly error, processing error and reverse backlash error of the multi-axis parallel platform by adopting a calibration test technology based on precision measurement, and uses these kinematic parameter errors to compensate for the current joint vector of each actuator, and adjusts the action of each actuator according to the compensated joint vector of each actuator to position the posture of the multi-axis parallel platform. Compared with the traditional direct feedback-free control method that only uses the initial ideal model, the compensation mechanism with embedded inherent errors of the parallel platform through pre-compensation can significantly reduce the influence of systematic error sources caused by model inaccuracy, manufacturing and assembly deviations, etc. on the end positioning accuracy, thereby effectively improving the positioning accuracy of the multi-axis parallel platform, making it suitable for more stringent high-precision application scenarios, while maintaining the inherent advantages of feedback-free control, simple structure, low cost, and no sensor delay.

[0036] Based on the content of the above embodiment, as an optional embodiment, in step S1, the system error of the multi-axis parallel platform is modeled as an assembly error, a processing error, and a reverse backlash error of each actuator in the multi-axis parallel platform, and the current joint vector of each actuator is compensated to obtain the compensated joint vector of each actuator. The method further includes: For any actuator among the actuators, obtain the actual forward displacement increment when any actuator moves forward to the position where the thread lost motion is zero, and obtain the actual reverse displacement increment when any actuator moves reversely from the position where the thread lost motion is zero to a stop; Based on the actual positive displacement increment and the actual negative displacement increment corresponding to each actuator, the negative lost motion error of each actuator during the motion steering is determined.

[0037] It should be noted that the source of the reverse backlash error is the clearance between the threads in the actuator transmission system, such as Figure 2 shown.

[0038] Specifically, in the embodiment of the present application, a bidirectional motion test is performed on each actuator in the multi-axis parallel platform. For any actuator, the actuator is connected to the host computer, and the host computer sends a positive displacement instruction x1 to the actuator to ensure that its thread pair is in close contact during the positive process. At this time, the thread idle stroke is zero. Then, the host computer sends a positive displacement instruction x1 to the actuator. 20 , the laser interferometer records the actual positive displacement increment Then, the host computer sends a reverse displacement instruction x to the actuator. 20 , record the actual reverse displacement increment .

[0039] In the embodiment of the present application, the reverse lost motion error of the actuator during the motion steering can be further determined based on the actual positive displacement increment and the actual reverse displacement increment corresponding to the actuator. Here, the measured reverse lost motion error is The following relations are satisfied: - .

[0040] In the embodiment of the present application, the displacement measurement system in the direction of motion of the actuator is, for example, a laser interferometer. Figure 3 In the measurement system shown, the actuator pushes the slider to move on the guide rail, driving the laser interferometer component on the slider to move.

[0041] In a specific embodiment of the present application, based on a bidirectional motion test of a multi-axis parallel platform, the reverse backlash error of each actuator in the multi-axis parallel platform during motion steering is obtained, and the specific steps include: Step 1: Obtain a first forward displacement instruction of the actuator of the multi-axis parallel platform.

[0042] Step 2: Control the actuator of the multi-axis parallel platform to move forward according to the first forward displacement instruction so that the thread pair of the actuator is in close contact during the forward displacement process.

[0043] Step three: After the threaded pair of the actuator is in close contact during the forward displacement process, a second forward displacement instruction of the actuator of the multi-axis parallel platform is obtained.

[0044] Step 4: Control the actuator of the multi-axis parallel platform to move forward according to the first forward displacement instruction, and measure the actual forward displacement increment of the thread pair.

[0045] Step 5: Obtain the reverse displacement command of the actuator of the multi-axis parallel platform.

[0046] Step six: controlling the actuator of the multi-axis parallel platform to move in the reverse direction according to the reverse displacement instruction, and measuring the actual reverse displacement increment of the thread pair.

[0047] Step seven, calculating the reverse backlash error of the actuator of the multi-axis parallel platform during motion steering based on the actual forward displacement increment and the actual reverse displacement increment.

[0048] In a specific embodiment of the present application, the actuator backlash compensation is performed to compensate for the screw thread backlash of the actuator reverse motion. Taking the six-axis parallel platform as an example, the joint vector of the parallel platform can be recorded as =[ i 1, i 2,…, i 6], the joint vector increment of each actuator of the parallel platform from position P0 to position P is: ; Where, i 1, i 2,…, i 6 represents the joint vectors of the first actuator, the second actuator, ..., the sixth actuator respectively; is the inverse kinematics solution function of the parallel platform; represents the joint vectors of each actuator of the parallel platform at the position P0; Represents the joint vectors of each actuator of the parallel platform at position P; the position P0 is represented by ( x 0, y 0, z 0, i x , i y , i z ) means, where ( x 0, y 0, z 0) represents the position coordinate, ( i x , i y , i z ) indicates posture; represents the increment of the joint vector of each actuator of the parallel platform; dth [i] represents the joint vector increment of the i-th actuator. If it is less than 0, it means that steering has occurred and reverse backlash error compensation is required.

[0049] The method of the embodiment of the present application performs a bidirectional motion test on each actuator in a multi-axis parallel platform, performs reverse clearance compensation on the actuator during the test, compensates for the thread lost motion of the actuator in the reverse motion, and obtains the reverse lost motion error of each actuator during the motion steering, which can ensure the accuracy and reliability of the reverse lost motion error calculation data of each actuator.

[0050] Based on the content of the above embodiment, as an optional embodiment, the steps of acquiring full-degree-of-freedom stepping test data of the multi-axis parallel platform specifically include: Determine the calibration stroke of the multi-axis parallel platform in each degree of freedom, and divide the calibration stroke in each degree of freedom into equal parts, and determine each measurement point in each degree of freedom and its corresponding theoretical position and posture of the step test; When the multi-axis parallel platform performs a step test on each degree of freedom, the actual position error of the measurement point corresponding to each step test on each degree of freedom is determined; According to the theoretical posture and actual posture error corresponding to each measurement point on each degree of freedom, the step test data on each degree of freedom is obtained; the degrees of freedom include translational degree of freedom and rotational degree of freedom.

[0051] Specifically, in the embodiments of the present application, assembly errors and machining errors can be determined by performing step tests on each degree of freedom of the multi-axis parallel platform using an external measuring instrument. The degrees of freedom include translational and rotational degrees of freedom, and the full degree of freedom step test data of the multi-axis parallel platform includes step test data for each translational degree of freedom and step test data for each rotational degree of freedom.

[0052] In an embodiment of the present application, the calibration stroke of the multi-axis parallel platform in each degree of freedom is determined, including determining the calibration stroke of the multi-axis parallel platform in each translational degree of freedom and each rotational degree of freedom, and dividing the calibration stroke on each degree of freedom into equal parts. Specifically, it is necessary to divide the calibration stroke on each translational degree of freedom and each rotational degree of freedom into equal parts, and then determine the theoretical displacement of each measurement point on each translational degree of freedom and its corresponding step test, as well as the theoretical posture of each measurement point on each rotational degree of freedom and its corresponding step test, thereby obtaining the theoretical posture of each measurement point on each degree of freedom and its corresponding step test.

[0053] Furthermore, when the multi-axis parallel platform performs a step test on each degree of freedom, the actual posture of the measurement point corresponding to each step test on each degree of freedom is obtained, and the actual posture error is calculated based on the theoretical posture and the actual posture, that is, the actual displacement error of the measurement point corresponding to each step test on each translational degree of freedom, and the actual posture error of the measurement point corresponding to each step test on each rotational degree of freedom are obtained, and finally the step test data on each degree of freedom are formed.

[0054] by x Taking axis displacement measurement as an example, the calibration stroke on a single degree of freedom is Tr, and the stroke is divided into n equal parts. This allows n measurement points to be determined along the calibration stroke. The displacement sensor's measuring head is fixed to the center of the multi-axis parallel platform, and the platform is stepped in steps of Tr / n. The theoretical displacement of each measurement point is Tr / n. The displacement sensor records the actual displacement after each step and subtracts it from the theoretical displacement, forming a point pair of the form [theoretical displacement, actual displacement error].

[0055] For x For rotational measurement on the rotational degree of freedom of the axis, fix the attitude sensor measuring head to the rotation axis of the parallel platform, and measure the theoretical attitude and attitude error of each measurement point in the same way as above to form a point pair in the form of [theoretical attitude, actual attitude error].

[0056] In a specific embodiment of the present application, the specific steps of obtaining full-degree-of-freedom stepping test data of a multi-axis parallel platform include: Step 1: for each translational degree of freedom, determine the calibration stroke of each translational degree of freedom.

[0057] Step 2: Divide the calibration stroke of each translational degree of freedom into n equal parts to obtain each measurement point in the calibration stroke and the theoretical displacement of each measurement point.

[0058] Step 3: Control the multi-axis parallel platform to perform step test with a step size of Tr / n; Tr represents the calibration stroke.

[0059] Step 4: Obtain the actual displacement of the corresponding measuring point after each step is completed, recorded by the displacement sensor located at the center of the multi-axis parallel platform.

[0060] Step 5: For each translational degree of freedom, determine the actual displacement error based on the actual displacement and theoretical displacement of each measurement point.

[0061] Step 6: For each translational degree of freedom, obtain the step test data of each translational degree of freedom based on the theoretical displacement and actual displacement error of each measurement point.

[0062] Step 7: For each rotational degree of freedom, determine the calibration stroke of each rotational degree of freedom.

[0063] Step eight, divide the calibration stroke of each rotational degree of freedom into n equal parts, and obtain each measurement point in the calibration stroke and the theoretical posture of each measurement point.

[0064] Step nine, control the multi-axis parallel platform to perform step test with a step length of Tr / n; Tr represents the calibration stroke.

[0065] Step 10: Obtain the actual posture of the corresponding measurement point after each stepping is completed, recorded by the posture sensor located at the rotation axis of the multi-axis parallel platform.

[0066] Step 11: For each rotational degree of freedom, determine the actual posture error based on the actual posture and theoretical posture of each measurement point.

[0067] Step 12: For each rotational degree of freedom, obtain the step test data of each rotational degree of freedom according to the theoretical posture and actual posture error of each measurement point.

[0068] The method of the embodiment of the present application divides the calibration stroke on each degree of freedom of the multi-axis parallel platform into equal parts, sets the theoretical posture of each measurement point on each degree of freedom and its corresponding step test to be the same, thereby simplifying the test data processing process, and then collecting the theoretical posture and actual posture error of each measurement point on each degree of freedom of the platform during the test to form step test data on each degree of freedom. This can improve the efficiency of obtaining step test data of all degrees of freedom of the platform while providing reliable technical data for the subsequent solution of assembly errors and processing errors.

[0069] Based on the content of the above embodiment, as an optional embodiment, the specific steps of solving the full-degree-of-freedom step test data of the multi-axis parallel platform to obtain the assembly error include: Based on the inverse kinematic equation of the multi-axis parallel platform, the kinematic error transmission equation of the actuator of the multi-axis parallel platform is determined; According to the theoretical pose and actual pose error corresponding to each measurement point on each degree of freedom, the linear coefficient between the theoretical pose and the actual pose error on each degree of freedom is determined; The assembly error is obtained by solving the kinematic error transfer equation and the linear coefficient corresponding to each degree of freedom.

[0070] Specifically, in an embodiment of the present application, the specific steps of calculating the assembly error based on the full-degree-of-freedom step test data include: Step 1: Determine the inverse kinematic equation of the multi-axis parallel platform.

[0071] Considering the general inverse kinematic solution of the parallel platform, it can be expressed as:

[0072] Where Θ represents the joint vector, m T represents the structural parameter vector of the multi-axis parallel platform (such as hinge position, rod length, etc.), m Indicates the number of structural parameters of the multi-axis parallel platform, x y z T Represents the end pose vector.

[0073] Step 2: Introduce the Jacobian matrix mapping and the parameter structure parameter sensitivity matrix to establish the differential relationship between assembly error and processing error, and construct the kinematic error transfer equation of the actuator of the multi-axis parallel platform, namely: ; in, is the kinematic Jacobian matrix, is the structural parameter sensitivity matrix.

[0074] In a multi-axis parallel platform with high repeatability and high positioning accuracy, assuming that the motion error of the actuator (the error caused by encoder control error and signal noise) is much smaller than the error caused by the structural parameters and assembly of the mechanism, the nonlinear residual of the repeatability error can be Replace as the kinematic error, and then construct the error transfer equation of the following form, namely: ; Step 3: Fit the linear coefficient between the theoretical pose and the actual pose error of each degree of freedom according to the theoretical pose and the actual pose error corresponding to each measurement point in the step test data of each degree of freedom.

[0075] Here, the degrees of freedom include translational and rotational degrees of freedom. For translational degrees of freedom, the corresponding terms are theoretical displacement, actual displacement, and actual displacement error; for rotational degrees of freedom, the corresponding terms are theoretical pose, actual pose, and actual pose error. To uniformly describe each degree of freedom, each can be described as theoretical pose, actual pose, and actual pose error.

[0076] More specifically, through x , y , z , i x , i y , i z The step measurement of six degrees of freedom can form the following error table for each degree of freedom, namely: ; Among them, for the translational degree of freedom, ..., represents the displacement of each measuring point, Represents the actual displacement error of the nth actual target point relative to the theoretical target point; for the rotational degree of freedom, ... Indicates the posture of each measurement point; Represents the actual attitude error of the nth actual target point relative to the theoretical target point.

[0077] Furthermore, err is calculated list The linear regression of , that is: ; Then we can get the linear relationship between the theoretical pose and pose error of each degree of freedom: ; in, Represents the linear coefficient.

[0078] Step 4: Solve the above kinematic error transfer equation and the linear coefficient corresponding to each degree of freedom to obtain the assembly error.

[0079] Specifically, after measuring each degree of freedom, the linear coefficient matrix consisting of the linear coefficients corresponding to each degree of freedom is obtained. k ,but k Should meet: ; in, It should be specified as all the structural parameters of the current multi-axis parallel platform. For example, for a multi-axis parallel platform including hinges a, b and rod length, x y z x T , solving this equation can give the assembly error .

[0080] The method of the embodiment of the present application, by combining the structural parameter characteristics of the multi-axis parallel platform, introduces the Jacobian matrix mapping and the parameter structure parameter sensitivity matrix on the basis of the general kinematic equation, establishes the differential relationship between the assembly error and the processing error, and constructs the kinematic error transfer equation of the actuator of the multi-axis parallel platform to solve the assembly error of the multi-axis parallel platform, which can effectively improve the accuracy and reliability of the assembly error calculation and provide reliable technical data for the subsequent compensation calculation of the actuator joint vector.

[0081] Based on the content of the above embodiment, as an optional embodiment, the specific steps of solving the full-degree-of-freedom step test data of the multi-axis parallel platform to obtain the machining error include: Determine the theoretical pose error corresponding to each measurement point on each degree of freedom based on the theoretical pose corresponding to each measurement point on each degree of freedom and the linear coefficient between the theoretical pose and the actual pose error on each degree of freedom; According to the theoretical actual posture error and the actual posture error corresponding to each measurement point on each degree of freedom, the residual corresponding to each measurement point on each degree of freedom is determined; The machining error is obtained by performing inverse solution based on the residual corresponding to each measurement point on each degree of freedom and the inverse kinematic equation of the multi-axis parallel platform.

[0082] Specifically, in the embodiment of the present application, the theoretical posture error corresponding to each measuring point on each degree of freedom is determined based on the theoretical posture corresponding to each measuring point on each degree of freedom and the linear coefficient between the theoretical posture and the actual posture error on each degree of freedom, wherein the theoretical posture error is the result of bringing the theoretical displacement (posture) of each measuring point into , k and x are known, we can get , which is the theoretical pose error.

[0083] Furthermore, in the embodiment of the present application, the residual corresponding to each measurement point on each degree of freedom is determined based on the theoretical actual posture error and the actual posture error corresponding to each measurement point on each degree of freedom, thereby establishing an error mapping table to compensate for the processing error. list The residuals at each measurement point form a list of the residuals for each degree of freedom , which can be expressed as: ; Residual list Contains the posture offset information caused by the machining error at each measurement point of each degree of freedom. 、 、 、 、 Represents the actual displacement (attitude) error corresponding to each degree of freedom; 、 、 、 、 、 Indicates the theoretical displacement (attitude) error corresponding to each degree of freedom.

[0084] Furthermore, in the embodiment of the present application, the machining error is obtained by performing an inverse solution based on the residual corresponding to each measurement point on each degree of freedom and the inverse kinematic equation of the multi-axis parallel platform. Specifically, the residual list can be calculated according to the following model: The residual is used to solve the inverse kinematics: ; Thus, the increment of the joint vector can be obtained , which is the machining error of the multi-axis parallel platform, which can be understood as the motion compensation value that needs to be added to the actuator due to the machining error.

[0085] In a specific embodiment of the present application, the specific steps of calculating the machining error based on the full-degree-of-freedom step test data of the multi-axis parallel platform include: Step 1: For each degree of freedom, determine the theoretical pose error based on the theoretical pose of each measurement point in the corresponding calibration stroke and the linear coefficient between the theoretical pose and the actual pose error.

[0086] Step 2: Determine the residual of each measurement point based on the actual posture error and theoretical posture error of each measurement point in the calibration stroke corresponding to each degree of freedom.

[0087] Step 3: Substitute the residual of each measurement point corresponding to each degree of freedom into the inverse kinematic equation of the multi-axis parallel platform for inverse solution to obtain the joint vector increment of each actuator of the multi-axis parallel platform, which is the machining error.

[0088] The method of the embodiment of the present application calculates the residual of the posture data of each measurement point on each degree of freedom by mining the linear coefficient between the theoretical posture and the actual posture error on each degree of freedom, and uses the residual corresponding to each measurement point on each degree of freedom and the inverse kinematic equation of the multi-axis parallel platform to perform inverse solution to solve the processing error, which can effectively improve the accuracy and reliability of the processing error calculation and provide reliable technical data for the subsequent compensation calculation of the actuator joint vector.

[0089] Figure 4 This is a schematic diagram of the structure of the multi-axis parallel platform provided in the embodiment of the present application. Figure 4 As shown, in the embodiment of the present application, the multi-axis parallel platform is a six-axis parallel positioning platform; The six-axis parallel positioning platform includes a base 1, a six-axis linkage mechanism 2 fixed above the base 1, and a moving platform 3 arranged above the six-axis linkage mechanism 2; The six-axis linkage mechanism 2 includes three fixed slots 21, each fixed slot 21 is provided with a ball slot mechanism 22 and two actuator mounting positions 23, wherein each actuator mounting position 23 is installed with an actuator 231; Each ball-slot mechanism 22 includes a metal ball 221, an inclined slot 222, and a guide rail 223. The metal ball 221 is located in the inclined slot 222. The top end of each metal ball 221 is connected to the moving platform 3. Each actuator 231 is used to push the inclined slot 222 to perform linear motion on the guide rail 223 , so that the inclined slot 222 and the metal ball 221 form a kinematic pair through point contact, so as to adjust the position of the moving platform 3 .

[0090] Specifically, in the embodiment of the present application, the six-axis parallel positioning platform includes a base 1, a six-axis linkage mechanism 2 and a moving platform 3. The three ball-slot mechanisms 22 (such as Figure 5As shown in the figure, the six-axis linkage mechanism 2 is arranged below the moving platform 3, and each ball groove mechanism 22 is arranged in the corresponding fixed groove 21 in the six-axis linkage mechanism 2. The fixed groove 21 is provided with an actuator mounting position 23, and the actuator 231 is installed on the fixed groove 21 through the actuator mounting position 23.

[0091] Each ball-and-slot mechanism 22 comprises a metal ball 221, an inclined slot 222, and a guide rail 223. The metal ball 221 is positioned within the inclined slot 222, which reciprocates along the guide rail 223. The top ends of the three metal balls 221 are threadedly connected to the movable platform 3. An actuator 231 is used to propel the corresponding inclined slot 222 linearly along the corresponding guide rail 223, forming a kinematic pair through point contact between the inclined slot 222 and the metal ball 221 to adjust the position of the movable platform 3.

[0092] Here, the six-axis parallel positioning platform achieves complete kinematic coupling with the moving platform 3 through six high-pair contact points on three sides. When the actuator 231 pushes the inclined slot 222, the kinematic coupling points of the ball-slot mechanism 22 change, thereby adjusting the position of the moving platform 3. Specifically, the moving platform 3 can be equipped with detectors such as CMOS and CCD sensors in the microscope imaging optical path.

[0093] Something that needs to be explained, Figure 6 In order to more clearly show the structural relationship, the metal ball and the inclined groove are shown in a non-contact state. In actual application, the two are always in contact.

[0094] Specifically, the above-mentioned six-axis parallel positioning platform based on dynamic coupling design is taken as an example to illustrate the implementation process of the multi-axis parallel platform positioning without feedback control provided by this application. For the six-axis parallel positioning platform with dynamic coupling design, its kinematic equation can be expressed in the following form, namely: ; in, i i Indicates its i joint parameters, [x,y,z, i x , i y , i z ] T The pose parameters representing its six degrees of freedom; q Represents the cotangent value of the chute angle in the platform structure, Represents the coupling diameter of the moving platform.

[0095] Backlash compensation is used to compensate for the thread lost motion of the linear actuator in reverse motion, i.e., the reverse lost motion error. The six actuator joint vectors are recorded as =[ i 1, i 2,…, i 6], is the inverse kinematics solution function of the six-axis parallel positioning platform. When moving from position P0 to position P, the joint vector increment of each actuator of the parallel platform is: ; Among them, δθ[i] represents the joint vector increment of the i-th actuator. If it is less than 0, it means that a turn has occurred, and the actuator needs to perform reverse backlash error compensation.

[0096] For the assembly error, in the six-axis parallel platform with dynamic coupling design, the main error is the cotangent value of the actual inclination angle of the inclined slot. q and coupling diameter dominant, so its structural parameters Specifically [ ], then the corresponding error transfer equation can be expressed as follows: ; After performing step measurement on the 3rd and 4th degrees of freedom of the platform using a laser interferometer, the corresponding linear coefficient matrix is ​​calculated. k ,but k Should meet: ; in F =[ ] T , solve this equation to get the assembly error .

[0097] After measuring all degrees of freedom, the residual list The residual is used to solve the inverse kinematics: ; The increment of the joint vector obtained , the motion compensation value that needs to be added to the machining error actuator can be obtained.

[0098] Finally, the compensated joint vectors of the six-axis parallel positioning platform actuator are calculated using the following compensation model: ,Right now:

[0099] Furthermore, the action of each actuator in the six-axis parallel positioning platform is adjusted according to the compensated joint vector of each actuator to achieve positioning of the position of its moving platform.

[0100] This application also provides an application scenario that utilizes the aforementioned multi-axis parallel platform positioning method. Specifically, the feedback-free multi-axis parallel platform positioning method provided in this embodiment can be applied in a microscopic imaging scenario. This scenario includes a multi-axis parallel platform positioning error compensation and positioning phase, and a microscopic imaging phase. The multi-axis parallel platform positioning method provided in this embodiment pertains to the multi-axis parallel platform positioning error compensation and positioning phase.

[0101] The method of the embodiment of the present application provides a six-axis parallel positioning platform based on dynamic coupling design. By combining the aforementioned multi-axis parallel platform positioning error compensation and positioning method, there is no need to introduce any sensor feedback, the volume of the entire device platform will not be increased, the cost is low, and high-precision positioning of the six-axis parallel platform without feedback control can be achieved under feedback control conditions.

[0102] The multi-axis parallel platform positioning device without feedback control provided in the present application is described below. The multi-axis parallel platform positioning device without feedback control described below and the multi-axis parallel platform positioning method without feedback control described above can be referenced to each other.

[0103] Figure 6 Schematic diagram of the structure of the multi-axis parallel platform positioning device without feedback control provided in the embodiment of the present application. It can be understood that the device can be applied to a multi-axis parallel platform including multiple actuators, such as Figure 6 As shown, the device includes: The compensation processing module 10 is configured to model the system error of the multi-axis parallel platform as an assembly error, a machining error, and a reverse lost motion error of each actuator in the multi-axis parallel platform, and compensate the current joint vector of each actuator to obtain a compensated joint vector of each actuator. The assembly error and the machining error are obtained by solving the full-degree-of-freedom stepping test data of the multi-axis parallel platform; the reverse lost motion error of each actuator is obtained by performing motion test analysis on each actuator. The posture positioning module 20 is used to adjust the action of each actuator according to the compensated joint vector of each actuator to position the posture of the multi-axis parallel platform.

[0104] It is understandable that the detailed functional implementation of each of the above units / modules can be found in the introduction of the aforementioned method embodiment, and will not be repeated here.

[0105] It should be understood that the above-mentioned device is used to execute the method in the above-mentioned embodiment. The implementation principle and technical effect of the corresponding program module in the device are similar to those described in the above-mentioned method. The working process of the device can refer to the corresponding process in the above-mentioned method and will not be repeated here.

[0106] The feedback-free controlled multi-axis parallel platform positioning device of the embodiment of the present application obtains the assembly error, processing error and reverse backlash error of the multi-axis parallel platform by adopting a calibration test technology based on precision measurement, and uses these kinematic parameter errors to compensate for the current joint vector of each actuator, and adjusts the action of each actuator according to the compensated joint vector of each actuator to position the posture of the multi-axis parallel platform. Compared with the traditional direct feedback-free control method that only uses the initial ideal model, the compensation mechanism with embedded inherent errors of the parallel platform through pre-compensation can significantly reduce the influence of systematic error sources caused by model inaccuracy, manufacturing and assembly deviations, etc. on the end positioning accuracy, thereby effectively improving the positioning accuracy of the multi-axis parallel platform, making it suitable for more stringent high-precision application scenarios, while maintaining the inherent advantages of feedback-free control, simple structure, low cost, and no sensor delay.

[0107] Based on the method in the above embodiment, the embodiment of the present application provides an electronic device, such as Figure 7 As shown, the electronic device may include: a processor (Processor) 710, a communication interface (Communications Interface) 720, a memory (Memory) 730 and a communication bus 740, wherein the processor 710, the communication interface 720, and the memory 730 communicate with each other via the communication bus 740. The processor 710 may call the logic instructions in the memory 730 to execute the method in the above embodiment.

[0108] In addition, the logic instructions in the aforementioned memory 730 can be implemented in the form of a software functional unit and, when sold or used as an independent product, can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application, or the portion that contributes to the prior art, or the portion of the technical solution, can be embodied in the form of a software product. The computer software product is stored in a storage medium and includes a number of instructions for enabling a computer device (which can be a personal computer, server, or network device, etc.) to execute all or part of the steps of the method described in each embodiment of the present application.

[0109] Based on the method in the above embodiment, an embodiment of the present application provides a computer-readable storage medium, which stores a computer program. When the computer program runs on a processor, the processor executes the method in the above embodiment.

[0110] Based on the method in the above embodiment, an embodiment of the present application provides a computer program product. When the computer program product runs on a processor, the processor executes the method in the above embodiment.

[0111] It is understood that the processor in the embodiments of the present application may be a central processing unit (CPU), other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field programmable gate arrays (FPGA), other programmable logic devices, transistor logic devices, hardware components, or any combination thereof. The general-purpose processor may be a microprocessor or any conventional processor.

[0112] The method steps in the embodiments of the present application can be implemented by hardware or by a processor executing software instructions. The software instructions can be composed of corresponding software modules, which can be stored in random access memory (RAM), flash memory, read-only memory (ROM), programmable read-only memory (PROM), erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), registers, hard disks, mobile hard disks, CD-ROMs, or any other form of storage medium known in the art. An exemplary storage medium is coupled to the processor so that the processor can read information from the storage medium and write information to the storage medium. Of course, the storage medium can also be an integral part of the processor. The processor and storage medium can be located in an ASIC.

[0113] The above embodiments can be implemented in whole or in part using software, hardware, firmware, or any combination thereof. When implemented using software, they can be implemented in whole or in part in the form of a computer program product. The computer program product comprises one or more computer instructions. When loaded and executed on a computer, the computer program instructions fully or partially produce the processes or functions described in the embodiments of this application. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions can be stored in a computer-readable storage medium or transmitted via the computer-readable storage medium. The computer instructions can be transmitted from one website, computer, server, or data center to another website, computer, server, or data center via wired (e.g., coaxial cable, optical fiber, digital subscriber line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.) means. The computer-readable storage medium can be any available medium accessible by a computer or a data storage device such as a server or data center that integrates one or more available media. The available medium can be magnetic media (e.g., floppy disk, hard disk, tape), optical media (e.g., DVD), or semiconductor media (e.g., solid-state drive (SSD)).

[0114] It will be understood that the various numerical numbers involved in the embodiments of the present application are merely distinctions for the convenience of description and are not intended to limit the scope of the embodiments of the present application.

[0115] It should be understood that expressions such as "include" and "may include" used in this application indicate the existence of the disclosed functions, operations, or constituent elements, and do not limit one or more additional functions, operations, and constituent elements. In this application, terms such as "include" and / or "have" may be interpreted as indicating specific characteristics, numbers, operations, constituent elements, components, or combinations thereof, but may not be interpreted as excluding the existence or possibility of adding one or more other characteristics, numbers, operations, constituent elements, components, or combinations thereof.

[0116] In the description of the embodiments of the present application, it should be noted that, unless otherwise clearly specified and limited, the term "connection" should be understood in a broad sense. For example, "connection" can be a detachable connection or a non-detachable connection; it can be a direct connection or an indirect connection through an intermediate medium. Among them, "fixed connection" means that the two are connected to each other and the relative position relationship after the connection remains unchanged. "Rotational connection" means that the two are connected to each other and can rotate relative to each other after the connection. "Sliding connection" means that the two are connected to each other and can slide relative to each other after the connection. The directional terms mentioned in the embodiments of the present application, such as "top", "bottom", "inside", "outside", "left", "right", etc., are only reference to the directions of the accompanying drawings. Therefore, the directional terms used are for better and clearer explanation and understanding of the embodiments of the present application, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the embodiments of the present application.

[0117] The above description is merely a specific embodiment of the present application, but the scope of protection of the present application is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in this application should be included in the scope of protection of this application. Therefore, the scope of protection of this application should be based on the scope of protection of the claims.

Claims

1. A multi-axis parallel platform positioning method without feedback control, characterized in that: include: The system error of the multi-axis parallel platform is modeled as an assembly error, a machining error, and a reverse lost motion error of each actuator in the multi-axis parallel platform, and the current joint vector of each actuator is compensated to obtain a compensated joint vector of each actuator; the assembly error and the machining error are obtained by solving the full-degree-of-freedom step test data of the multi-axis parallel platform; the reverse lost motion error of each actuator is obtained by performing motion test analysis on each actuator; The action of each actuator is adjusted according to the compensated joint vector of each actuator to position the posture of the multi-axis parallel platform.

2. The multi-axis parallel platform positioning method without feedback control according to claim 1, characterized in that: Before modeling the system error of the multi-axis parallel platform as an assembly error, a machining error, and a reverse backlash error of each actuator in the multi-axis parallel platform, and compensating the current joint vector of each actuator to obtain the compensated joint vector of each actuator, the method further includes: For any of the actuators, obtaining an actual forward displacement increment when the actuator moves forward to a position where the thread lost motion is zero, and obtaining an actual reverse displacement increment when the actuator moves reversely from a position where the thread lost motion is zero to a stop; Based on the actual positive displacement increment and the actual reverse displacement increment corresponding to each of the actuators, a reverse lost motion error of each of the actuators during motion steering is determined.

3. The multi-axis parallel platform positioning method without feedback control according to claim 1, characterized in that: The steps for acquiring full-degree-of-freedom stepping test data of the multi-axis parallel platform specifically include: Determine the calibration stroke of the multi-axis parallel platform in each degree of freedom, and divide the calibration stroke in each degree of freedom into equal parts, and determine each measurement point in each degree of freedom and its corresponding theoretical pose of the step test; When the multi-axis parallel platform performs a step test on each degree of freedom, determining an actual posture error of a measurement point corresponding to each step test on each degree of freedom; According to the theoretical posture and actual posture error corresponding to each measurement point on each degree of freedom, step test data on each degree of freedom is obtained; the degrees of freedom include translational degree of freedom and rotational degree of freedom.

4. The multi-axis parallel platform positioning method without feedback control according to claim 3, characterized in that: The specific steps of calculating the full-degree-of-freedom step test data of the multi-axis parallel platform to obtain the assembly error include: Determining a kinematic error transfer equation of an actuator of the multi-axis parallel platform based on an inverse kinematic equation of the multi-axis parallel platform; Determine a linear coefficient between the theoretical pose and the actual pose error for each measurement point on each degree of freedom according to the theoretical pose and the actual pose error corresponding to each measurement point on each degree of freedom; The assembly error is obtained by solving the kinematic error transfer equation and the linear coefficient corresponding to each degree of freedom.

5. The multi-axis parallel platform positioning method without feedback control according to claim 4, characterized in that: Solving the full-degree-of-freedom step test data of the multi-axis parallel platform to obtain the machining error, the specific steps include: Determine the theoretical pose error corresponding to each measuring point on each degree of freedom according to the theoretical pose corresponding to each measuring point on each degree of freedom and the linear coefficient between the theoretical pose and the actual pose error on each degree of freedom; Determining a residual corresponding to each measurement point on each degree of freedom according to a theoretical actual posture error and an actual posture error corresponding to each measurement point on each degree of freedom; The machining error is obtained by performing an inverse solution based on the residual corresponding to each measurement point on each degree of freedom and the inverse kinematic equation of the multi-axis parallel platform.

6. The multi-axis parallel platform positioning method without feedback control according to any one of claims 1 to 5, characterized in that: The multi-axis parallel platform is a six-axis parallel positioning platform; The six-axis parallel positioning platform includes a base, a six-axis linkage mechanism fixed above the base, and a moving platform arranged above the six-axis linkage mechanism; The six-axis linkage mechanism includes three fixed slots, each of which is provided with a ball slot mechanism and two actuator mounting positions, wherein each of the actuator mounting positions is provided with an actuator; Each of the ball-slot mechanisms comprises a metal ball, an inclined slot, and a guide rail; the metal ball is located in the inclined slot; and the top end of each metal ball is connected to the moving platform; Each of the actuators is used to push the inclined slot to perform linear motion on the guide rail, so that the inclined slot and the metal ball form a kinematic pair through point contact, so as to adjust the posture of the moving platform.

7. A multi-axis parallel platform positioning device without feedback control, characterized in that: include: a compensation processing module, configured to model the system error of the multi-axis parallel platform as an assembly error, a machining error, and a reverse lost motion error of each actuator in the multi-axis parallel platform, and compensate a current joint vector of each actuator to obtain a compensated joint vector of each actuator; the assembly error and the machining error are obtained by solving full-degree-of-freedom stepping test data of the multi-axis parallel platform; and the reverse lost motion error of each actuator is obtained by performing motion test analysis on each actuator; The posture positioning module is used to adjust the action of each actuator according to the compensated joint vector of each actuator to position the posture of the multi-axis parallel platform.

8. An electronic device, characterized in that: include: at least one memory for storing a computer program; At least one processor is used to execute the program stored in the memory. When the program stored in the memory is executed, the processor is used to execute the method according to any one of claims 1 to 6.

9. A computer-readable storage medium storing a computer program, characterized in that: When the computer program is executed on a processor, the processor is caused to execute the method according to any one of claims 1 to 6.

10. A computer program product, characterized in that When the computer program product is run on a processor, the processor is enabled to perform the method according to any one of claims 1 to 6.

Images