Patent ID: 6232889
Filing Date: 2001-05-15
Classification: G08G

Abstract:
A system for controlling passage of one or more vehicles through an intersection having signal lights such that the one or more vehicles may preempt the signal lights, the system comprising:a mobile unit capable of being mounted in the one or more vehicles, wherein the mobile unit has a compass for measuring a magnetic heading of the one or more vehicles; anda base unit capable of being connected to a controller of the signal lights of the intersection, the base unit being configured to adjust the magnetic heading received from the mobile unit by a number of degrees equal to the number of degrees that the intersection is offset from being aligned in a substantially North/South and East/West configuration, the base unit being configured to produce at least one output signal which is dependent on the adjusted magnetic heading of the one or more vehicles, wherein the at least one output signal is recevied by the controller which preempts the normal operation of the signal lights and causes the signal lights to respond in a prescribed manner to the one or more vehicles.