Emergency vehicle maneuvers and control laws for automated highway systems

The operation and transit of emergency vehicles (EVs) on an automated highway system (AHS) designed under the control architecture proposed in the California PATH (Partners for Advanced Transit and Highways) program is described. The term "EVs" is used in a general sense to describe vehicles such as police cars, ambulances and tow trucks, that may service faults inside or outside the AHS. The transit of EVs requires intensive participation of the coordination layer, which directs the interactions of neighboring vehicles, and the link layer, which regulates traffic flow along stretches of highway. Various strategies for these two hierarchical layers that are needed to assign high-priority transit to EVs on the AHS are described. These coordination- and link-layer maneuvers circulate other vehicles around the EV in both free-flowing and stopped traffic.