This paper explores the notion and usefulness of nonstationary velocity profiles for high priority emergency vehicle transit on automated highways. These profiles are intended for use in the link layer of the hierarchical control architecture defined by the California Partners for Automated Transit and Highways (PATH) program. A non-stationary velocity profile which can be used to circulate traffic around a faster moving emergency vehicle is introduced. The effects on traffic flow are illustrated. A traffic flow controller that sustains nonstationary velocity profiles on fully automated highways is designed. Controller stability is discussed stressing the usefulness of nonstationary velocity profiles in creating a moving area of low vehicle density. Simulation results obtained using SmartCap, a traffic flow simulation program, demonstrate the fast circulation of an emergency vehicle in AHS while high traffic flow is maintained.

Issue Section:
Technical Papers
Keywords:
automated highways, emergency services, hierarchical systems, traffic control, stability
Topics:
Control equipment, Density, Highways, Traffic, Vehicles, Emergencies, Flow (Dynamics), Feedback
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Copyright © 2002
 by ASME
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