Air Vehicle Control Using Multiple Control Surfaces

This research is investigating the use of wide span, smoothly varying control surfaces placed on the leading and trailing edges of a wing to control cruise and maneuver performance of a representative combat unmanned vehicle. The purpose of the research is to understand the desired mechanical characteristics as well as the optimum deflection distribution in the spanwise and chordwise directions. In particular we are looking for the shapes of the control surfaces such that roll, pitch, and yaw control are performance requirements are met while the necessary input energy (actuator) is minimized during maneuvering phase of a mission. We are also looking at using the same set of control surfaces to minimize the induced drag during the cruise, loiter and dash portions of the flight profile. Several objective functions where investigated to gain insight into minimizing the actuator requirements. The optimization schemes satisfied equilibrium conditions. Results indicate and that the deflection distribution of the control surfaces is strongly dependent on the selected objective function, and that the desired shapes of the surfaces range from a linear variation to a parabolic distribution. Nomenclature b Span (ft) c Chord (ft) S Wing area (ft 2 ) α L C Lift coefficient due to angle of attack p L C Roll moment coefficient due to roll rate