Experimental PC based TGPID control method for 2D CNC machine

An important problem in the control of circular motion of CNC machine is to let X and Y axes move simultaneously. This article addresses this problem for the performance of desktop-scale CNC milling machine for reducing roundness error (REB), minimizing position time difference (ΔTt). An approach that can solve those problems will be introduced. Our approach uses a Taguchi–Grey System–Proportional Integral Derivative (TGPID). This method emphasizes an improvement of system performance through this controller’s robustness, such as a faster initialization in gaining as appropriate local minima and also high responsive. In this paper, it is aimed to enhance on multi-performance characteristics, namely actual radius (R_act) and position time (Tt). The improvement of roundness error in counter-clockwise (CCW) direction is from 0.151 mm by default, being 0.140 mm by TPID (Taguchi–PID; without grey system), and 0.133 mm by TGPID. The method can reduce the roundness error significantly, also the difference of position time for 100%. This proposed method also offers a simple experimental-based approach. An improvement of its performance indicated that this proposed approach is applied successfully to multi-linear motion performance optimization which is determined by many parameters at multi-quality performances. Performances of the proposed controller scheme, as well as some practical design aspects, are demonstrated by the control of a circular motion of CNC machine.