Architecture and Algorithm for a Laboratory Vehicle Collision Avoidance System

In this paper we describe the application architecture for a collision avoidance system developed for a fleet of sensorless mobile vehicles. The system has been deployed in the IT Convergence Lab in the Coordinated Science Laboratory at the University of Illinois at Urbana-Champaign, which is a testbed for studying system architecture for networked embedded control systems. We describe several factors that a well designed collision avoidance algorithm needs to address, and discuss some of the tradeoffs and design decisions that need to be made. The solution that we have developed has a minimal effect on existing components for higher level functionality, as well their interfaces. The architecture and algorithm provide a low level safety guarantee regardless of higher level objectives. The architecture exploits the infrastructure and services provided by the control domain middleware, called Etherware, which has been developed in the laboratory. Indeed, the development of the collision avoidance system shows the usefulness of the specific services and abstractions that Etherware provides to the application designer in facilitating rapid system design and deployment.