Calculation of unmanned aerial vehicle positioning coordinates when dropping agricultural loads

Abstract

In some agricultural processes, an unmanned aerial vehicle (UAV) delivers fertilizers, crop protection products, water and water solutions. The drop of material objects (load) can be controlled by a microprocessor installed on the UAV by means of an algorithm-based program. The authors conducted theoretical studies to develop a mathematical model of the load motion when it is dropped from a low-flying UAV and an algorithm for determining the moment of load drop to reach a given landing point using the known flight parameters. The study identified factors influencing the trajectory of the dropped material objects and posed the problem of determining the distance from the point of load dropping from the UAV to the required landing point. The article presents systems of differential equations of load motion without air resistance and with a quadratic dependence of the air resistance force on the drop velocity. Curves are constructed to determine the moment of load drop simplistically using the velocity and flight altitude of the UAV. The equations for calculating the final horizontal component of the loads drop velocity, the tangent angle and duration of its drop, as well as the required distance are given. The arguments of the found functions are ballistic coefficient, speed and flight altitude of the UAV. The authors note the necessity of refining the obtained solutions by taking into account the dependence of the parameters of the dropped loads on the wind speed and direction, as well as precipitation and atmospheric pressure. The article presents an algorithm of automatic control of the reset of material objects dropping by an on-board eight-bit processor with cyclic implementation of the duration of incoming information processing.