Sideslip-roll composite turn control for a tailless aerial vehicle with flexible performance constraints.

Abstract

Considering flight safety and ride comfort, aircraft are usually not allowed to sideslip. However, compared to manned aircraft, unmanned aircraft can improve combat performance by appropriately reducing the safety factor. For example, a small sideslip of the aircraft may be utilized to reduce the roll angle to lower the radar cross-section. According to the requirements of ultra-low altitude penetration and inspired by the frequent drifting of cars participating in snow rallies when turning, we investigate the feasibility of sideslip-roll composite turn control for a tailless aerial vehicle (TAV) with high-precision trajectory tracking. Firstly, the TAV's non-affine and affine models for controller-oriented design are developed for the translational and rotational subsystems respectively. Secondly, a flexible funnel control method with a new error transformation function is proposed to obtain good transient and steady-state performance. Thirdly, a sideslip-roll composite turn control strategy is proposed to improve maneuverability based on the flight-path angle rate allocation method. Finally, A nonlinear dynamic inverse (NDI) controller is constructed for the TAV attitude loop. Simulation results show that the designed control method is strongly robust and can achieve the difficult ultra-low altitude penetration task.