A STUDY OF THE IMPACT OF WORKPIECE LOCATION ON MACHINING PERFORMANCE OF A 2-DOF PKM BASED MACHINE TOOL

摘要

This paper presents the impact of workpiece location on the machining performance of a 2 - degree of freedom Parallel Kinematic Machine (PKM) tool. The PKM behavior is highly non-uniform and depends on the tool position within the workspace. The structural deformation and vibration due to cutting loads affect the quality of machined surfaces. The aim of the present study is to find the optimal tool position (workpiece location) where the workpiece is machined to a specific quality level. End-milling operations are carried out at various locations within the workspace and the surface roughness of machined surface (R_a) is measured at each location. A regression model is developed to predict the surface roughness. The study shows that the workpiece location has significant impact upon surface roughness of the machined part. Finally, a suitable workspace is defined for end-milling operation.