A study on machining capability of a 2-DoF PKM-based milling machine

In the recent past, Parallel Kinematic Machines (PKM) with fixed-length legs have been claimed for their potential use as machine tools due to smaller moving masses leading to the high dynamic characteristics and accuracy. In this paper, the machining capability of a 2-Degrees-of-Freedom (DoF) PKM-based milling machine is explored. Stiffness of the PKM was estimated using finite element analysis approach. Extensive experimentation was carried out by varying machining conditions, i.e., cutting speed, feed rate and depth of emit to study the variation in performance measures, namely, surface roughness and material removal rate. Regression models were developed to predict the surface roughness. An attempt was made to find the optimum machining conditions for PKM using Genetic Algorithm. The experimental results confirm the capability of fixed-length leg PKM-based machine tool to perform machining operations upon metals like hard Aluminium alloys. (C) 2013 The Authors. Published by Elsevier Ltd.