Flatness-based Finite-Horizon Multi-UAV Formation Trajectory Planning and Directionally Aware Collision Avoidance Tracking

TL;DR

This paper introduces a flatness-based finite-horizon control method for multi-UAV formation planning and collision avoidance, eliminating reliance on numerical methods and incorporating a directionally aware collision strategy.

Contribution

It presents a novel collision-free formation control scheme using differential flatness and Pontryagin's principle, with a directionally aware collision avoidance strategy.

Findings

Effective formation trajectory planning without numerical methods

Collision avoidance prioritizes forward path UAVs

Simulation validates control scheme's effectiveness

Abstract

Optimal collision-free formation control of the unmanned aerial vehicle (UAV) is a challenge. The state-of-the-art optimal control approaches often rely on numerical methods sensitive to initial guesses. This paper presents an innovative collision-free finite-time formation control scheme for multiple UAVs leveraging the differential flatness of the UAV dynamics, eliminating the need for numerical methods. We formulate a finite-time optimal control problem to plan a formation trajectory for feasible initial states. This optimal control problem in formation trajectory planning involves a collective performance index to meet the formation requirements to achieve relative positions and velocity consensus. It is solved by applying Pontryagin's principle. Subsequently, a collision-constrained regulating problem is addressed to ensure collision-free tracking of the planned formation trajectory. The tracking problem incorporates a directionally aware collision avoidance strategy that prioritizes avoiding UAVs in the forward path and relative approach. It assigns lower priority to those on the sides with an oblique relative approach, disregarding UAVs behind and not in the relative approach. The high-fidelity simulation results validate the effectiveness of the proposed control scheme.