Automatic guidance system for trackless vehicles - has circuit to generate phase difference signals to control system steering along AC cable in road surface

摘要

An automatic guidance system utilises signal phase shift to control the steering of a trackless vehicle, which has a horizontally positioned coil together with a vertical coil in which voltage signals are induced as the vehicle passes over a cable in-set into the road surface. The cable carries an a.c. signal. The coil (13,14) signals are amplified (20,23) and are mixed (26,27) with signal generated by an oscillator driven (28) one out of four bit counter (30). Comparator stage (21,22) monitor the phase differences of the signals to generate a command for the steering unit using a microprocessor control unit (25).