Biaxial contouring control using H^∞ pole placement design

This paper presents an H^∞ pole placement method, under a weighted mixed sensitivity problem, to design robust axis controllers in which the selection of weighting functions is investigated according to the relaxed performance measure. The objective is to independently design motion controllers using the notion of relaxed performance measure to reduce the dynamic contouring error, i.e., the cross-the-path error, in multiaxis servomechanisms. Experimental results from a biaxial servomechanism show that the H^∞ pole-placement method for axis controller design can effectively reduce contouring error by matching axis delay times and hence achieve good contouring accuracy.