Research and Development of an Automatic Variable Rate Fertilizer Applicator for Cassava

Abstract

          ^{Plant production technology, according to the specific fertility of the site, is applying the technology as plant requirements and according to each location such as seed sowing rate, fertilizer sowing rate and pesticide control rate. The purpose of this study was to investigate and develop "an Automatic Variable Rate Fertilizer Applicator for Cassava." The micro-controller (Arduino mega 2560) controlled the speed of the DC motors (24 V, 500 W) which are driven to sow tree fertilizers for 3 tanks. This machine controlled through the PWM (Pulse Width Modulation) signal and used an encoder to measure the ground wheel speed. The results showed that the accuracy of the 46-0-0, 18-46 and 0-0-60 fertilizer rate tests were 91.55%, 90.26% and 94.07% respectively. In addition, testing of an automated variable rate fertilizer applicator in the cassava field revealed that the average field was 4.79 rai hr-1 at average travelling speed of tractor 1.17 m s-1, average field efficiency was 75.43% and average fuel consumption was 0.69 l rai-1}