Robust control of a compact disc player

The design of robust controllers for a compact disc mechanism is considered. Using mu synthesis, a controller has been designed for good track-following. The design problem involves time-domain constraints on signals and robustness requirements for norm-bounded structured plant uncertainty. It is shown that by using weighting functions in the mu framework this problem can be solved, but at the cost of many design iterations. The mu controller has been implemented in an experimental setup with a digitally controlled compact disc player.<>