A study of the impact of machine tool structure on machining processes

This paper deals with parallel kinematics machine (PKM) applications for high speed machining. PKM behaviour is anisotropic, so structural deflection due to cutting loads generates different defects in the machined part, according to tool position and orientation in the workspace. The aim of the present study is the definition of a mechanical workspace where the part is machined to a specified quality level. Models of the machine tool structure, the load generated by the cutting phenomena and the machined surface are used to determine this workspace and are applied to a tricept structure with telescopic legs for grooving and drilling operations. A simulation shows that leg deflection gives rise to defects of the machined entity which are evaluated with respect to tool position and orientation. Finally, a mechanical workspace is defined for a drilling process using a tricept structure machine tool.