Resistor sensors: Two resistor sensors were added underneath the linear actuators to enable the position of each actuator to be known at any time. The resistor sensors sent an integer to the PLC from 0-1800.

Encoders: The encoders were added as an additional way to track the movements of the and position of the mower. They were screwed into a metal piece extending outside of the wheels. Because the encoder axel did not line up perfectly with the wheel axel (<= 1cm off), to ensure nothing broke, I attached the axels together by a flexible tube.  

GPS: More on this subject can be found on the ‘GPS TRACKING & RTK’ page