Design of a disturbance accommodating controller an airbrone pointing device

This paper describes the practical application of "Disturbance Accommodating Control Theory" to a high-performance laser pointing (sighting) device mounted in a helicopter. The disturbances considered include the fundamental and first harmonic rotor-induced vibrations, weapon recoils, and a general class of uncertain pitching motions. It is shown that the disturbance accommodating controller can be designed by systemmatic linear algebraic techniques using state variables. The final controller is completely linear and yields a controller "transfer function" having rather unique properties in terms of controller poles and zeroes. The comparative pointing accuracy of the laser device using both a commercially designed classical controller and our "disturbance accommodating" controller is studied via analog simulation. By this means, it is shown that the proposed disturbance accommodating controller can (ideally) improve laser pointing accuracy by 2500%, compared to the classical controller.