The development here opens new possibilities for
conventional-based multivariable control design. Eqs.
(7)-( 13) allow the designer to simultaneously monitor
closed-loop stability and performance in all the feedback
channels as the system gain and relative gains are
varied. This design strategy is intended to relieve some
of the burdens encountered with sequential loop closuredesign strategies, as well as directly extend Evans
concepts to fully coupled control system architectures.
Even with the results presented here, the multivariable
design problem is formidable. Selection of actuatorsensor
pairs and compensation still confront the
designer. However, rather than conducting the design as
a sequential process, the "design knobs" illustrated in
Fig. 2 can be used to tailor system behavior under a
unifying perspective.