Distributed Obstacle and Multi-Robot Collision Avoidance in Uncertain Environments

TL;DR

This paper presents a distributed control framework for heterogeneous multi-robot systems that ensures obstacle avoidance, collision prevention, and robust communication in uncertain environments, validated through simulations and experiments.

Contribution

It introduces a novel distributed NI-based formation control, dynamic topology adaptation, and a UAV-assisted tracking method for reliable multi-robot coordination.

Findings

Successful obstacle and collision avoidance demonstrated

Formation control with dynamic shape adaptation achieved

UAV tracking effectively maintained formation in experiments

Abstract

This paper tackles the distributed leader-follower (L-F) control problem for heterogeneous mobile robots in unknown environments requiring obstacle avoidance, inter-robot collision avoidance, and reliable robot communications. To prevent an inter-robot collision, we employ a virtual propulsive force between robots. For obstacle avoidance, we present a novel distributed Negative-Imaginary (NI) variant formation tracking control approach and a dynamic network topology methodology which allows the formation to change its shape and the robot to switch their roles. In the case of communication or sensor loss, a UAV, controlled by a Strictly-Negative-Imaginary (SNI) controller with good wind resistance characteristics, is utilized to track the position of the UGV formation using its camera. Simulations and indoor experiments have been conducted to validate the proposed methods.