Traditional type fertilizer broadcasters were with constant opening with gravity flow method which was showing high variation in discharge quantity of fertilizer between the rows and this lead to under and over dosage. A battery operated variable rate fertilizer broadcaster was developed and it consisting of storage tank, metering unit, spreading unit and variable rate controller unit was developed. To standardize the metering mechanism for the fertilizer applicator, a study was conducted on the existing fertilizer metering devices. Based on the literatures, fluted roller feeding mechanism was selected for the development of fertiliser applicator, since the positive feeding mechanism results in accurate variations of the discharge rate by adjusting the exposed length of the fluted roller. The performance evaluation of the developed variable rate fertilizer broadcaster was conducted in laboratory to confirm its discharge in various exposure lengths of fluted roller as well as the spread pattern test to measure the coefficient of variation which is used to determine and express the uniformity of distribution of the application. It was observed that the application rate of 28, 64, 95 and 140 kg ha-1 could be achieved for 10, 20, 30 and 40 mm exposure length of flute respectively. The coefficients of variation were , , and per cent in application rates for 10, 20, 30 and 40 mm exposure length of flute respectively. The actual field capacity of the developed unit was observed as ha h -1 . The efficiency of the machine is 83 per cent. | Development of fertilizer broadcaster with electronically controlled fluted roller metering mechanism for paddy crop
