Real time parameter based contour error estimation algorithms for free form contour following

In order to improve the contour error accuracy of two-dimensional linear motor, an improved cross-coupled control (CCC) scheme combining real-time contour error estimation and model-free adaptive control (MFAC) is proposed. The real-time contour error estimation method is based on CCC theory and coordinate transformation idea. It can accurately determine the contour error point of regular contour and avoid the influence of tracking error on the contour error. At the same time, for the design of two-axis error controller, only the input and output data generated by two-dimensional linear motor in reciprocating motion are used to design a multiple input multiple output-model-free adaptive control (MIMO-MFAC) algorithm, this algorithm avoids the dependence on accurate mathematical model and reduces the control difficulty. The experimental comparison showed that the proposed method improves the system tracking accuracy and contour accuracy, and verifies the proposed method correctness and effectiveness.

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Iterative Learning Cross-Coupled Control for XY Table Based on Real-Time Contour Error Estimation

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.383-390.7054 ◽

2011 ◽

Vol 383-390 ◽

pp. 7054-7059 ◽

Cited By ~ 1

Author(s):

Li Mei Wang ◽

Qi Yang ◽

Yi Biao Sun ◽

Chun Fang Liu

Keyword(s):

Real Time ◽

External Disturbance ◽

Iterative Learning ◽

Free Form ◽

Contour Error ◽

Dynamic Matching ◽

Linear Motors ◽

Control Scheme ◽

Table Model ◽

Estimate Method

The contour accuracy of XY table directly driven by two linear motors was influenced by the complicated reel-time contour error model of free-form curves, uncertainty external disturbance and dynamic matching between X axis and Y axis. To establish XY table model that easily calculated and suitable for free-form curves, real-time contour error estimate method was adopted. In order to reduce uncertainty external disturbance and dynamic matching between X axis and Y axis, the iterative learning cross-coupled controller (ILCCC) was designed for current compensation on X axis and Y axis. Simulation results show that the control scheme can enhance the robustness of the system, and effectively improve the XY table of contour precision.

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Real-Time Contour Error Estimation with NURBS Interpolator

2018 2nd International Conference on Robotics and Automation Sciences (ICRAS) ◽

10.1109/icras.2018.8443187 ◽

2018 ◽

Author(s):

Hongjian Zhang ◽

Xiaoyong Ni ◽

Pan Hu ◽

Youjia Yuan

Keyword(s):

Real Time ◽

Error Estimation ◽

Contour Error ◽

Nurbs Interpolator

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Two Dimensional Intelligent Feedrate Control Incorporating Stage Dynamics

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.764-765.653 ◽

2015 ◽

Vol 764-765 ◽

pp. 653-657

Author(s):

Kuan Chen Lin ◽

Chun Hsien Huang

Keyword(s):

Real Time ◽

Traditional Method ◽

Control Design ◽

Industrial Applications ◽

Free Form ◽

Contour Error ◽

Dynamic Factor ◽

Two Dimensional ◽

B Spline ◽

Path Curvature

This paper studies the dynamic feedrate control problem for mechanical stages performing contouring actions. In modern researches, feedrate is considered as a dynamic factor instead of simple constant value in the traditional methods, and should be properly controlled to meet higher precision standard nowadays. To incorporate the dynamic feedrate in the path interpolation, the so called non-uniform rational B-spline (NURBS) algorithm is utilized to form the fundamental real-time interpolation structure of this research. The result of a sophisticated intelligent feedrate control design is then proposed where the system feedrate is real-time determined based on both the feedback of the path curvature and the measured contour error. Experiments and comparative studies for free-form paths are also conducted where the results show that the proposed design indeed can provide significant precision improvement in overall contouring performance in contrast to the traditional method. Therefore, the effectiveness and the goal of the proposed method can be verified which suggests that the entire scheme has the potential for real industrial applications.

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Cross-coupled control based on real-time Double Circle contour error estimation for biaxial motion system

Measurement and Control ◽

10.1177/0020294021993830 ◽

2021 ◽

Vol 54 (3-4) ◽

pp. 324-335

Author(s):

Li Bo ◽

Wang Taiyong ◽

Wang Peng

Keyword(s):

Real Time ◽

Error Estimation ◽

Approximation Method ◽

Control Strategy ◽

Estimation Method ◽

Contour Error ◽

Motion System ◽

Contour Machining ◽

And Control ◽

Error Estimation Method

In contour machining, contour error is a major factor affecting machining quality. In order to improve the performance of contour following, many control techniques based on real-time contour error estimation have been developed. In this paper, a Double Circle contour error estimation method is proposed. First, based on the kinematic information of the reference point on the command trajectory, five interpolation points closest to the actual point are obtained. Then the approximate contour error is obtained by employing the Double Circle approximation method. Compared with the common contour error approximation methods, the proposed method can achieve high precision approximation. In addition, according to the proposed contour error approximation method, the cross-coupled control strategy is improved. Experiments prove the effectiveness of the proposed estimation method and control strategy.

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