Eigenstructure assignment for handling qualities in helicopter flight control law design

The requirements of active control technology, together with increased operational demands, presents a range of new problems for the designers of helicopter flight control laws. Multivariable control system design techniques, such as eigenstructure assignment, provide a potentially powerful set of tools for control law development which take account of the inherently multi-input multi-output nature of the helicopter. This paper examines the use of eigenstructure assignment for the design of control laws based on state variable feedback. The merits of this approach are examined through the use of an illustrative design example with particular emphasis being given to decoupling and robustness properties