Distributed Predefined Time Sliding Mode 3D Formation Control of Uavs

This paper addresses the 3D formation control of unmanned aerial vehicles (UAVs) by proposing a distributed predefined-time sliding mode control method. The system consists of multiple UAVs guided by a virtual leader. A distributed predefined-time state observer (DPTSO) is designed to estimate the position and velocity of the virtual leader within a predefined time. Based on these estimates, a nonsingular predefined-time sliding mode control law is developed for each UAV to maintain a desired relative position within the formation. This control law ensures that the formation tracking error converges to zero within a predefined time. Simulations involving four underactuated UAVs validate the effectiveness of the proposed control scheme, demonstrating robust performance under varying disturbances.