Improving machine tool accuracy by a direct position measurement using a new approach of laser goniometry

摘要

Parallel kinematics machines (PKMs) present a promising new formation of machine kinematics. But, their application is limited due to insufficient positioning precision, which follows from errors of the transformation model and an indirect position measurement. To overcome these problems the development of an optical direct position measurement is presented. Three laser goniometric modules are used to measure six angles between fixed points and the PKM platform, which characterize the platform position and orientation completely. Each angle is determined with high precision using an additional reference laser beam and a CCD line sensor.