  A basic task in the design of an industrial robot application is the relative
placement of robot and workpiece. Process points are defined in Cartesian
coordinates relative to the workpiece coordinate system, and the workpiece has
to be located such that the robot can reach all points. Finding such a location
is still an iterative procedure based on the developers' intuition. One
difficulty is the choice of one of the several solutions of the backward
transform of a typical 6R robot. % combined with the limited range of the axes.
We present a novel algorithm that simultaneously optimizes the workpiece
location and the robot configuration at all process points using higher order
optimization algorithms. A key ingredient is the extension of the robot with a
virtual prismatic axis. The practical feasibility of the approach is shown with
an example using a commercial industrial robot.
