A Formation Reconfiguration Mechanism for Aerial Cable Towed Systems against Thrust Loss

This article focuses on the formation reconfiguration mechanism for an aerial cable towed system (ACTS), which is composed of three quadrotors manipulating a point-mass payload. The system dynamics are analyzed in depth, which yields a refined decoupled model under actuator faults by utilizing the variation linearization technique and coordinate transformations. Based on this model, a fixed-time sliding mode observer is applied to estimate the degree of thrust degradation. The estimates are used for analyzing and optimizing the capacity margin under thrust loss fault, which reconfigures the desired formation. Leader-follower controllers are then designed to track the planned trajectory with the desired formation. Finally, simulation results demonstrate the effectiveness of the proposed method.