Broadcast Guidance of Multi-Agent Systems

Abstract

We consider the emergent behavior of a group of mobile agents guided by an exogenous broadcast signal. The agents’ dynamics is modelled by single integrators and they are assumed oblivious to their own position, however they share a common orientation (i.e. they have compasses). The broadcast control, a desired velocity vector, is detected by arbitrary subgroups of agents,that upon receipt of the guidance signal become "ad-hoc" leaders. The control signal and the set of leaders are assumed to be constant over some considerable intervals in time. A system without "ad-hoc" leaders is referred to as autonomous. The autonomous rule of motion is identical for all agents and is a gathering process ensuring a cohesive group. The agents that become leaders upon receipt of the exogenous control add the detected broadcast velocity to the velocity vector dictated by the autonomous rule of motion. This paradigm was considered in conjunction with several models of cohesive dynamics, linear and non-linear, with fixed inter-agent interaction topology, as well as systems with neighborhood based topology determined by the inter-agent distances. The autonomous dynamics of the models considered provides cohesion to the swarm, while, upon detection of a broadcast velocity vector, the leaders guide the group of agents in the direction of the control. For each local cohesion interaction model we analyse the effect of the broadcast velocity and of the set of leaders on the emergent behavior of the system. We show that in all cases considered the swarm moves in the direction of the broadcast velocity signal with speed set by the number of agents receiving the control and in a constellation determined by the model and the subset of "ad-hoc" leaders. All results are illustrated by simulations.