Mondo Knows Facts
Under-road induction loops trigger green traffic lights for vehicles
Embedded wire coils detect metal car bodies to operate automatic traffic signals
Many traffic signal intersections use inductive loop sensors embedded in shallow pavement grooves beneath the asphalt. Passing cars and lorries alter the magnetic field created by electrical wire coils, signalling the traffic control computer that a vehicle is waiting at the stop line.
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Tags: traffic, sensors, roads
Under-road induction loops trigger green traffic lights for vehicles: the short answers
- Where does this come from, and can I check it?
- Embedded wire coils detect metal car bodies to operate automatic traffic signals. The figure is taken from NIST, which is linked in full on this page. Every fact on Mondo Knows names its source rather than repeating an unsourced claim.
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