Comparative analysis between using an articulated arm robot and a conventional machine in milling applications

Abstract

The scope of this article is to perform a comparative analysis between low force milling operations performed by an articulated arm industrial robot and a conventional milling machine on an aluminium workpiece. The research sought to compare the machining force levels, tool behaviour and surface aspect in order to identify the nature of stiffness limitations for industrial robots. The expected force levels under normal circumstance were up to 100 N. The experiments were conducted using a Kawasaki FS 10 E articulated arm robot with six degrees of freedom. The experimental data was collected using a Kistler 9257B dynamometer. The experimental procedures were first conducted using the industrial robot approach. Several milling passes were performed using both full radial tool engagement and a lateral depth of cut equal to 2/3 of the tool diameter. The machining force values were compared for each axis, with focus on both machining force levels, variations and resulted surface aspect. Regarding tool behaviour and machining results, these aspects were observed directly during and after each operation. The main conclusion of the experimental procedures was that the biggest stiffness issues appeared along Z axis and also appeared with greater chip thickness.