Bearing-based Simultaneous Localization and Affine Formation Tracking for Fixed-wing Unmanned Aerial Vehicles

This paper studies the bearing-based simultaneous localization and affine formation tracking (SLAFT) control problem for fixed-wing unmanned aerial vehicles (UAVs). In the considered problem, only a small set of UAVs, named leaders, can obtain their global positions, and the other UAVs only have access to bearing information relative to their neighbors. To address the problem, we propose novel schemes by integrating the distributed bearing-based self-localization algorithm and the observer-based affine formation tracking controller. The designed localization algorithm estimates the global position by using inter-UAV bearing measurements, and the observer-based controller tracks the desired formation with the estimated positions. A key distinction of our approach is extending the SLAFT control scheme to the bearing-based coordination of nonholonomic UAV systems, where the desired inter-UAV bearings can be time-varying, instead of constant ones assumed in most of the existing results. Two control schemes with different convergence rates are designed to meet desired task requirements under different conditions. The stability analysis of the two schemes for SLAFT control is proved, and numerous simulations are carried out to validate the theoretical analysis.