Adjustment time and offset of a system for spatially variable rate fertilisation

The aim of this research is to measure the adjustment time and offset of a cheap system for spatially variable rate fertilisation, designed, developed and set up by the Mechanics Section of I.T.A.F. Department. In order to test the system, a centrifugal fertiliser spreader, working by gravity, was modified connecting an actuator with the two hopper shutter slides. Two different actuator types were tested, in order to measure the accordingly variable adjustment time and offset. The adjustment offset of the centrifugal spreader increases with increasing machine average forward speed and decreases with increasing fertiliser rate, considering the same rate variation. The main components of the system can be mounted on different agricultural machines for spatially variable rate crop input application.