Control algorithms for stiffening an elastic industrial robot

An industrial robot (IR) position-control algorithm will be presented that was developed at the Fraunhofer Institute for the highly accurate cutting of geometrically complex metal surfaces. In the past the extreme tolerance requirements for hard alloy workpieces had to be met manually or by means of expensive specialized machine tools. It is shown that this advanced manufacturing task can be solved by a conventional IR if its elastic behavior can be sufficiently stiffened by the introduction of a more sophisticated control concept. Experiences with the design and the practical implementation will be discussed.