Guidelines and procedures are developed for specifying the location and spacing of sensors needed and used by algorithms which detect freeway incidents. The sensor placement problem is considered for each of the following geometric features: freeways containing only level, tangential sections of roadway with on and off ramps; freeways containing weaving areas of between 1000 and 3000 feet (305 and 914 M); freeway segments containing a change in the number of lanes; and freeway segments with a change in the alignment. The guidelines and procedures permit the user to determine the optimum spacing of sensor stations given the roadway geometry, the funding available for sensor installation, and the requirements for incident detection algorithm performance. Major emphasis is placed upon assessing the tradeoffs between cost and effectiveness of a variety of candidate sensor configurations.
Abstract