In this study, the authors propose a hierarchical control architecture for dealing with faults and adverse environmental conditions on an Automated Highway System (AHS). The faults are classified according to the capabilities remaining on the vehicle or roadside after the fault has occurred. Information about these capabilities is used by supervisors in each of the layers to select appropriate control strategies. The extended control strategies that are needed by these supervisors in each layer of the hierarchy are outlined. A companion paper, abstracted in PATH Database record no. 9597, develops and verifies protocols for extended coordination strategies and maneuvers.

In this report the authors present a unified framework for carrying out safety calculations for the automated highway problem and obtain sufficient conditions for a set of continuous controllers to be safe and use these conditions to design a discrete scheme that switches between them. Guarantees of safety for the closed loop hybrid system follow by design/

This report presents an evaluation of the Phase II Smart Card Demonstration Project, the goal of which is to develop a transit fare payment system for commercialization that will improve transit efficiency and effectiveness. The major focus of the project is the testing of selected technologies in revenue service. Two types of fare payment cards were selected: a contactless radio frequency (RF) card and a contact card. The advanced fare payment system includes passenger transaction units installed on buses and the associated control and communications system. The evaluation covers the following areas: functional performance of hardware and software components, impacts on transit management, operations and efficiency, transit passenger responses and perceptions, and institutional and organizational issues related to the planning and implementation of the Field Operational Test.