Modeling and simulation of mass-actuated flexible aircraft for roll control

Abstract

Moving mass control (MMC) is a flight control technique that provides several unique advantages over conventional aerodynamic control surfaces, particularly for near space vehicles. In this study, we propose an MMC strategy for roll control of low-speed flexible HALE aircraft. Two internal moving masses are used to produce rolling moment rather than conventional ailerons. The complete equations of motion of the flexible aircraft carrying moving mass are first derived in terms of quasi-coordinates. A simplified model integrated with unsteady aerodynamic loads is obtained for roll control. The effect of moving mass positions on rigid-body motion and aeroelasticity couplings are analyzed. The feasibility of the mass-actuation concept for roll control of the flexible aircraft is primarily proven. The roll control ability and aeroelastic characteristics can be improved through the reasonable design of the moving mass system. The dynamic behavior of the system, while the mass travels along the wing, is simulated, implying that the elastic motion induces the delay effect in the roll motion of the flexible model compared with the rigid model. A roll rate control system is designed and analyzed to demonstrate the feasibility of using moving masses in real-time flight control.