Design of magnetic steering sensors for a serpentine driverless vehicle

A combination of vertically and horizontally oriented magnetic sensing coils is arranged to provide a signal that is used to control the steering of a driverless passenger vehicle. The vehicle is powered by induction from primary coils placed beneath the roadway. A secondary pick up coil on the underside of the vehicle must be maintained directly above the primary coil track in order to maximise the power transferred to the vehicle. Thus the steering system is required to operate over the widest possible range in order to handle corners and power failures so that the vehicle can be brought back on track and continue normal operation without the intervention of a driver. A sensor coil design based on spatial convolution is described and some of the trade offs listed. Finally theoretical computations are presented together with experimental results for comparison