A robotic lawnmower system comprising an robotic lawnmower comprising a plurality of sensors (170), wherein the controller is configured for receiving a signal through a first sensor (170') and determining a first signal qualifier for the first sensor (170'); receiving a signal through a second sensor (170") and determining a second signal qualifier for the at least one second sensor (170"); comparing the first signal qualifier and the at least one second signal qualifier; and selecting the sensor (170) providing the highest signal qualifier for synchronisation.
