A QFT controller design implementation for a worm gear driven manipulator joint

Abstract

Quantitative feedback theory (QFT) design technology is used in conjunction with a parametric model of a robot manipulator joint driven by a worm gear transmission. The plant family of this system contains both stable and unstable members and it is of interest to design a controller that will stabilize the entire family and provide acceptable performance. A nominal loop transfer function containing a nonminimum phase controller is shaped. It is found that controller bandwidth is a key for successful implementation.