Decentralized Multi-Robot Encirclement of a 3D Target with Guaranteed Collision Avoidance

TL;DR

This paper introduces a decentralized control framework enabling multiple robots to encircle a moving 3D target while guaranteeing collision avoidance, validated through simulations and real-world experiments.

Contribution

It proposes three variations of a control strategy for multi-robot encirclement, including an extension for maintaining safe inter-robot distances, all with local communication.

Findings

Effective encirclement demonstrated in simulations and experiments.

Decentralized approach requires only local communication.

Guarantees collision avoidance among robots.

Abstract

We present a control framework for achieving encirclement of a target moving in 3D using a multi-robot system. Three variations of a basic control strategy are proposed for different versions of the encirclement problem, and their effectiveness is formally established. An extension ensuring maintenance of a safe inter-robot distance is also discussed. The proposed framework is fully decentralized and only requires local communication among robots; in particular, each robot locally estimates all the relevant global quantities. We validate the proposed strategy through simulations on kinematic point robots and quadrotor UAVs, as well as experiments on differential-drive wheeled mobile robots.