Determining Optimal Piecewise Polynomial Coefficients for the Electronic Cam in the CNC Sanding Mechanism

Abstract

In this paper, an optimal Electrical Cam (Ecam) profile is obtained by identifying the best breakpoint positions for piecewise polynomials using the cubic spline interpolation method. To achieve a curve that best tracks the reference Ecam curve, the breakpoint positions are determined using particle swarm optimization with random inertia weight (RNW-PSO). The previous programmable logic controller (PLC) used in the sanding mechanism was the DELTA DVP40ES2, utilizing the Ecam capability of DELTA ASD-A2 servo motors. To implement the Ecam function independently of the servo motor type, it has been integrated into a PLC, specifically the SIEMENS SIMATIC CPU 1215C. The optimized Ecam curve is then applied to a computer numerical control (CNC) sanding machine. Practical results demonstrate the effectiveness of the proposed method, showing improved sanding quality and better compliance with the reference curve.

Keywords

• cubic spline interpolation
• ecam
• cnc sanding machine
• rnw–pso