Distance-Based Adaptive Formation Control With Guaranteed Collision Avoidance and Connectivity Maintenance

In this article, a distance-based adaptive formation control scheme is proposed for a group of agents with external disturbances and unknown parameters. Different from the existing results, global stability of the closed-loop system can be guaranteed even if the desired formation framework is nonminimally or noninfinitesimally rigid. A distance bound selection method is presented to transform the problem of avoiding ambiguous formation shapes, collision, and connectivity interruption to a constrained control problem. A prescribed performance bound technique is utilized to restrict the distances into the preset ranges, and an adaptive law is designed for each agent to estimate the unknown parameters. It is shown that the proposed scheme can ensure the boundedness of all the closed-loop system signals, and the distance constraints are not violated. Finally, simulation results are presented to demonstrate the effectiveness of the proposed scheme.

I. Introduction

In Recent years, formation control of multiagent systems has attracted considerable attention due to its wide application [1], [2]. According to the topological structure and required measurable signals [3], formation control schemes can be roughly classified into displacement-based, distance-based, bearing-based, and angle-based approaches. In displacement-based [4], [5] and bearing-based [6], [7], [8] schemes, relative states to neighboring agents should be measured in orientation aligned local coordinate systems (or global coordinate system). In contrast, distance-based [9], [10], [11], [12], [13], [14], [15], [16], [17], [18], [19] and angle-based [20], [21] schemes only need the relative states in unaligned local coordinate systems. Without the prealignment procedure, agents can use the local sensors (RGB-D camera for instance) to measure the required signals, which make such methods well suited for GPS-denied environments.