A MODEL FOR MEASURING THE EFFECT OF TIRE PRESSURE AND DRIVING SPEED ON HORIZONTAL SPRAYER BOOM MOVEMENTS AND SPRAY PATTERN

There are a number of reasons for incorrect spray distributions but horizontal boom vibrations, effected by soil unevenness, are a major cause of irregular spray patterns. A modal model of a flexible sprayer boom was developed, based on experimental measurements and modal analysis techniques to investigate horizontal boom vibrations and the related spray pattern. Field input forces were simulated with a tractor and mounted sprayer driven over a standardized bumpy road. The modal model and the input force were combined in a forced response technique to simulate the boom movement by which the spray deposit distribution was computed. A comparison of the spray patterns with different tire pressures and driving speeds gave an optimal range of use for the tested sprayer, tractor and tires. This method allows rapid testing of new sprayer designs.