A magnetoresistive three-axis magnetometer was designed, fabricated, characterized and tested with the purpose of detecting vehicles on highways. The magnetoresistive (MR) magnetometer sensor element is a permalloy (NiFe) thin-film deposited on silicon. The sensors are fabricated using equipment similar to integrated circuit manufacturing, so many sensors can be produced on a single silicon wafer. The sensor has three orthogonal sensing axes and uses a 1 kohm permalloy transducer (a Wheatstone-bridge) that uses the 'barber-pole' method of biasing the sensitivity curve. Testing included measurements at in-use roadway test sites. Magnetic signatures of vehicles were collected and post-test analyzed by applying a detection algorithm. Detection accuracy was greater than 99 % for all types of vehicles passing over the detectors. The sensors are low cost and can be packaged with simple electronics to make a low-cost vehicle detector.
A solid-state vehicle detector for roadway applications
Ein magnetfeldabhängiger Halbleitersensor für das Detektieren von Fahrzeugen auf der Autobahn
1995
6 Seiten, 12 Bilder, 2 Tabellen, 2 Quellen
Aufsatz (Konferenz)
Englisch
A solid-state vehicle detector for roadway applications
Kraftfahrwesen | 1995
|A Solid-State Vehicle Detector for Roadway Applications
British Library Conference Proceedings | 1995
|