Formation control of unmanned rotorcraft systems with state constraints and inter-agent collision avoidance

Abstract

In this paper, we present a novel framework and control laws for the formation of multiple unmanned rotorcraft systems, be it single-rotor helicopters or multi-copters, with physical constraints and with inter-agent collision avoidance, in cluttered environments. The proposed technique consists of a closed-form analytical consensus control solution in the free space and an optimization-based motion planning protocol for inter-agent and obstacle collision avoidance. More specifically, a consensus control law is designed to tackle a series of state constraints, that is, the physical limitations of velocity, acceleration and jerk, and an optimization-based motion planning technique is utilized to generate solutions when the consensus control fails to provide a collision-free trajectory. The stability of the switching process between the consensus control and motion planning is guaranteed by a sufficiency condition. The effectiveness of the proposed technique is successfully demonstrated through both simulation and real flight experiments.