An approach to developing variable-rate sprayer technologies is to install electronic control systems on conventional sprayers. This study introduces a direct injection type electronic solution concentration control system. This control system was installed on a field sprayer, and then a map-based variable-rate sprayer was developed. The control system consisted of a chemical tank, a chemical metering pump, the metering pump’s driver, the metering pump’s speed sensor, the implement’s travelling speed sensor, an Electronic Control Unit (ECU), a GPS receiver and a mixing unit. The metering pump discharge was measured at different carrier liquid (water) working pressures (3, 4 and 5 bar) and different chemical metering pump shaft speed (100, 200, 300 and... |