Green transport system: a technology demonstration of adaptive road lighting with giant magnetoresistive sensor network for energy efficiency and reducing light pollution

Abstract

To enhance energy efficiency and reduce light pollution of overnight road lighting in suburban traffic, we propose a novel green transport system based on giant magnetoresistive (GMR) sensors. The basic principle is to detect the perturbation to the earth magnetic field by a ferrous vehicle with GMR sensors. This system can switch on the road lighting to full illumination gradually before the motor vehicle arrives and dim it out after the vehicle leaves without the driver noticing. Based on a sparse suburban road in the countryside of Hong Kong, a demonstration model was constructed to illustrate its feasibility. GMR sensors and the associated electrical energy control components including signal processors, relays, and dimmers were integrated into a complete system. The experimental result indicates that the sensing principle is feasible and the whole system can function together coherently to achieve over 90% energy saving. Such system can be scaled up to be implemented in real road conditions. © (2013) Trans Tech Publications, Switzerland.