This self-guide lawnmower follows electrical cord laid under the grass on your lawn which is turned on when you want to mow. This path is in left side of simulator.
The right side is lawnmower with two separate drive wheels. Each motor was connected to a coil that picks up the induced current from wire under the grass. The coils wound in opposite directions cancel each other out when mower exactly straddles the electric cord. If mower strays to the side one motor stops until other wheel brings machine over electric guide cord.
This was made using coils, an audio amplifier, a transformer, with sensitive relays and relays.
I wonder if normally open reed switches connected to opposite wheels would work with the correct sensitivity where the SPST switches are in the motor circuit?
