Generation of normalized tool vector from 3-axis CL data and its application to a mold polishing robot

Cutter location (CL) data with normal vectors can be used for not only a desired trajectory of tool's translational motions but also a desired force direction for molds. In this paper, such normalized tool vectors from 3-axis CL data are generated for a polishing robot. The resultant CL data allow the polishing robot based on an industrial robot to realize a teaching-less operation of position and force. The present robot can also control the polishing force consisting of the contact and kinetic friction forces. During the polishing of a mold, a position feedback loop has a delicate contribution to the force feedback loop in Cartesian space so as not to make the tool deviate from the desired trajectory. The effectiveness and validity of the proposed robot have been proved by actual polishing experiments using an aluminum mold with curved surface.