Experimental implementation of Taylor series expansion error compensation on a bi-axial CNC machine

Int J Adv Manuf Technol

Chen

2016

Contouring errors calculated from the tracking errors of the individual servo drives is one of the important factors that affect machining accuracy. Through the precompensation of the tracking errors the contouring error can be reduced. This paper builds the prediction model of the tracking error, based on which iterative pre-compensation scheme is proposed, to achieve the optimum precompensation value without running servo drives repetitively. Simulation and experiment results verify that the tracking error can be predicted accurately by the prediction model and the iterative pre-compensation scheme of the tracking error can reduce the contouring error effectively.

Section: Introductionmentioning

confidence: 99%

Iterative pre-compensation scheme of tracking error for contouring error reduction

Int J Adv Manuf Technol

Chen

2016

“…Zhu et al [7] proposed a real time contouring error estimator based on the second-order Taylor approximant of the point-to-curve distance function. Moreover, some advanced controllers were combined with CCC to improve the contouring performance of CNC platform, such as robust tracking controller [8], Taylor series expansion error compensator [9], generalized cross-coupled controller [10], and hierarchical optimal contour controller [11], etc.…”

Section: Introductionmentioning

confidence: 99%

“…Although the existing works [5][6][7][8][9][10][11] can reduce contouring errors, they were confined to two-or three-axis machines with only translational joints. The nonlinear kinematics of five-axis machines complicate the contouring error control, which thus needs more sophisticate controller design [12].…”

Section: Introductionmentioning

confidence: 99%

Contouring error control of the tool center point function for five-axis machine tools based on model predictive control

Yang

Int J Adv Manuf Technol

Ding

2016

In five-axis machining processes, tool center point (TCP) control is often used to adjust the orientation of the ball end milling while maintaining constant tool center point coordinates in the workpiece frame. Therefore, TCP contouring error decreases the quality of the machined surface, but very few efforts have been made so far to minimize the contouring error of five-axis TCP by feedback control. To this end, a model predictive control (MPC) method is developed here for rolling optimization. More precisely, the contouring error model of five-axis TCP function is developed, where a Jacobian matrix is used to approximate the relationship between the contouring error and five drivers' tracking errors. The MPC algorithm is afterwards derived, where constraints of control signals are considered as well to avoid violation of the power limitation of the drivers. Finally, the proposed MPC method is examined by extensive experiments using testing tool path of ISO 10791-6: 2014 to verify its effectiveness and superiority.

“…Xi et al. 19,20 proposed a model-based Taylor series expansion error compensation (TSEEC) aiming at eliminating the contour error of linear and circular contours by predicting the contour error and compensating it in the next d step, where d represents the delay of the identified model. Huo et al.…”

Section: Introductionmentioning

confidence: 99%

A zero phase error tracking based path precompensation method for high-speed machining

Proceedings of the Institution of Mechanical Engineers, Part C:

Zhao

et al. 2015

Contour error due to the dynamic characteristics of feed system has a great influence on machining accuracy, in highspeed machining. In this paper, a new path precompensation method is proposed using zero phase error tracking control algorithm to improve the contouring accuracy for multiaxis machining with large feed rates. In this method, the outputs are predicted with the identified position-loop models of feed systems, and a contour error calculator is designed to calculate contour error in each sample instance using the predicted output and reference input. In order to compensate the contour error resulting from the dynamic tracking error of feed systems, the contour error vector is decomposed orthogonally and the compensation components for individual axis are calculated using zero phase error tracking control algorithm. Simulations showed that contour errors can be significantly improved with small compensation using the new path precompensation method for linear, circular, and parabola contours. Experimental results showed that the new method can reduce contour error significantly and achieve a better compensation compared with zero phase error tracking control and cross-coupled path pre-compensation.