Roads/Highways

Normal Communication Networks require the Sender to specify the address of the Receiver before communication can take place. In problems that a rise in an Automated Vehicle Highway System, the Sender can identify the Receiver by its physical location only (i.e. a car wanting to communicate with the car immediately in front of it). Normal Communication Procedures that use the Receiver's Address to establish communication must be preceded by an Address Finding Protocol. An Address Finding Protocol which uses the Absoulate Location of vehicles has been proposed in [2] and is reviewed in...

This report presents a vehicle reidentification algorithm for consecutive detector stations on a freeway, whereby a vehicle measurement made at a downstream detector station is matched with the vehicle's corresponding measurement at an upstream station. The algorithm should improve freeway surveillance by measuring the actual vehicle travel times; these are simply the differences in the times that each (matched) vehicle arrives to the upstream and downstream stations. Thus, it will be possible to quantify conditions between widely spaced detector stations rather than assuming that the...

The Institute of Transportation Studies (ITS) is assisting the California Department of Transportation (CALTRANS) to establish and conduct a program of advanced highway technology R&D to obtain better productivity from the States’ most used highway segments. The Program on Advanced Technology for the High-way, PATH, centers on advanced technology opportunities that may contribute to the relief of traffic congestion, with related problems of air pollution and parking; and on energy for transportation, in particular continued use of petroleum based fuels.

A new version of a field-deployable real-time laser-based detection system has been developed using new techniques of electronics and optics. The laser-based non-intrusive detection system uses a laser line that is projected onto the ground as a probe. The reflected light is collected and focused into a photodiode array by an optical system. Vehicle presence is detected based on the absence of reflected laser light. By placing two identical laser/sensor pairs at a known distance apart, the speeds of both the front and rear of a vehicle are measured based on the times when each sensor is...