A servomechanism controller design tool

A controller design technique for a range of positioning servomechanisms was required. Each servo was to deliver an identical performance using different brushless DC motor, leadscrew and carriage components. The components were selected dependent upon space and available power. Performance was defined in terms of sensitivity and complementary sensitivity functions. From these, weighting functions were derived and used in an H_∞ optimization to find a suitable control algorithm. The same weighting functions could then be used for servomechanisms using different components, so achieving similar performance without further control engineer design input. Tests for stability within parameter tolerance ranges and overall performance confidence checks were developed. The process was used on two servomechanisms