This book is motivated by the following technological developments: high quality
integrated sensors and actuators, powerful control processors that can implement
complex control algorithms, and powerful computer hardware and software that can
be used to design and analyze control systems. We believe that these technological
developments have the following rami cations for linear controller design:
When many high quality sensors and actuators are incorporated into the de-
sign of a system, sophisticated control algorithms can outperform the simple
control algorithms that have su ced in the past.
Current methods of computer-aided control system design underutilize avail-
able computing power and need to be rethought.
This book is one small step in the directions suggested by these rami cations.
We have several goals in writing this text:
To give a clear description of how we might formulate the linear controller
design problem, without regard for how we may actually solve it, modeling
fundamental specications as opposed to speci cations that are artifacts of a
particular method used to solve the design problem.
To show that a wide (but incomplete) class of linear controller design problems
can be cast as convex optimization problems.
To argue that solving the controller design problems in this restricted class is
in some sense fundamentally tractable: although it involves more computing
than the standard methods that have \analytical" solutions, it involves much
less computing than a global parameter search. This provides a partial answer
to the question of how to use available computing power to design controllers.
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