Roughness Measurement of Polished Beech Wood by a Robotic Arm with a Laser Rangefinder

Abstract

In the past, rough measurement mostly used contact or non-contact needle instruments to measure the surface profile along a straight line and could not match the diversified production behavior patterns. The programs that analyze the measurement data all include Gaussian filters. The ISO standard series on Gaussian filtering has been published. Improper usage of Gaussian filtration can completely deform surface images and underestimate or overestimate calculated parameters. The purpose of this paper is to show that the laser rangefinder can be quickly installed and used with Matlab software to reversely restore 3D images so that an operator can visually see the surface changes of a workpiece before and after grinding and polishing. The non-contact laser rangefinder measures samples milled with different grinding particle sizes: no. 80, 120, and 240. By using Gaussian filters with different cutoff wavelengths of 0.25 mm, 0.8 mm, 2.5 mm, and 8 mm, the influence of improper parameters on the Ra value of the workpiece surface roughness is discussed. In the experiments, the suitable grinding particle size for European beech wood polishing is analyzed as 80.