Eigenstructure Control: A flight vehicle handling qualities design tool

With the development of high reliability sensors, computers and actuators, it is now possible to build flight vehicle control systems with extraordinary performance. Indeed full authority fly-by-wire flight vehicles using feedback controllers can substantially mask the basic airframe dynamic characteristics and consequently its performance limitations. These technology developments in turn have brought into focus the role of multivariable control system design methods to evolve complex multi-loop systems using multiple sensors and control effectors. Multivariable control techniques are now being demonstrated in experimental flight research programs. It is thus reasonable to expect that these methods will be used in flight vehicle control design of production aircraft as increased sophistication in airframe design and performance is sought. Among the many control techniques available for such design, Eigenstructure Control techniques offer some unique advantages since the flight vehicle handling qualities requirements originate in the modal control framework. The present study explores methods to adapt this method for deriving practical flight control laws.