Hybrid State System Development for Autonomous Vehicle Control in Urban Scenarios

This paper analyzes a hybrid-state-system-based controller for an autonomous vehicle in urban traffic and provides development procedures for hybrid-state systems for automatic control. The OhioState University Autonomous City Transport utilizes a discrete-state system, based on a finite state machine for high-level decision making and a continuous-state controller for low-level lateral and longitudinal control. The design procedure for the overall hybrid controller involves a series of capability grafts, each improving the ability of the vehicle to handle diverse situations. The design methodology, as demonstrated in a number of development steps, and architecture are capable of handling various urban scenarios, as demonstrated in a June 2007 site visit by Darpa officials.