Design and Performance Test of Embeded Module Metering Device for Variable Rate Fertilizer Applicator

Abstract

Uniform rate of fertilizer application (URA) practice is disregarding the productive potential of the various areas within the field. Thus, it is not efficient method because some area is less fertilized and other is over fertilized. With variable rate application (VRA) machines, the dose and the position of application could be given precisely as required by crops. Machinery with variable rate capabilities impressed as technologically sophisticated and expensive. In Indonesia, implementation of VRT in crop production is also still questioned, because fear of the complicated and expensive prices of the machines. Therefore the objective of this research is to develop an embeded system for variable metering device of granular applicator. The metering was equipped with two rotor, which could be operated as single rotor or double rotor. The dose of granular fertilizer could be controlled by controlling the rotation of the rotor. The rotation of the rotor was controlled using digital PID algorithm. The result of the test showed that using single rotor the output of urea, SP-36 and NPK are 0.84, 0.96 and 1.2 g/rotation respectively. Test on double rotor showed that the output of urea, SP-36 and NPK are 1.14, 2.22 and 2.1 g/rotation respectively. All results showed that the prototype of metering device can control fertilizer dose of urea, SP-36 and NPK fertilizer precisely with coefficient of determination of more than R2=0.99. For field operation in the future, the developed VRT applicator will be mounted on multi-purpose vehicle which was modified from riding type rice transplanter. Position of the vehicle in the field will be acquired using agriculture type RTK DGPS.