LOOP VS ULTRASONIC IN CHICAGO: ULTRASONIC VEHICLE DETECTOR FIELD TEST ISOLATING DIFFUSED REFLECTION AND ENDURING HARSH ENVIRONMENT

Evaluation of ultrasonic detector (USD) against inductive loop detector (ILD) was conducted on the freeway in Chicago, USA for four seasons, in cooperation with the Illinois Department of Transportation (IDOT), Illinois, USA and Matsushita Communication Industrial (Panasonic), Yokohama, Japan. USD is the major vehicle detector in Japan, while ILD is the primary one in the USA. USD is easily operable in the existing traffic control system in USA, and keeps good performance and durability under the condition of heavy traffic and harsh environment of summer heat and winter freeze in Chicago. Also new algorithm for pulse ultrasonic vehicle detection to isolate diffused reflection is effective beneath the overpass on noisy freeway in Chicago. USD is one of the promising non-intrusive vehicle detectors and acceptable for various ITS applications. For the covering abstract see IRRD E102946.