UAV Performing Level Turn Maneuver Under CG Offset: Backstepping Control Scheme

Abstract

When an Unmanned Aerial Vehicle (UAV) experiences uneven cargo loading or release, the center of gravity (c.g.) undergoes a lateral shift, leading to complex coupled and non-linear asymmetric dynamics. This poses significant challenges in controlling the UAV, particularly during lateral/directional maneuvers. To ensure the UAV's safety and stability, it becomes imperative to implement nonlinear control strategies. This study tackles the issue by first ad-hoc modeling the asymmetric dynamics and then effectively transforming them into strict feedback form. This transformation guarantees the desired level turn maneuver performance for a fixed-wing UAV, even when facing lateral center of gravity shifts. Subsequently, a backstepping control approach is developed to enable autonomous maneuver execution. Simulation results illustrate that the maneuver performance under lateral asymmetry closely resembles that of the symmetric case, demonstrating the effectiveness and need of the proposed control strategy in handling such scenarios.