Method and apparatus for prescription application of products to an agricultural field

摘要

A prescription farming control system includes a navigation controller and a product delivery controller for controlling the rate of operation of a number of agricultural product delivery mechanisms mounted on an applicator vehicle as a function of the global position of the vehicle in an agricultural field. Information is stored in computer memory on board the vehicle to define a number of layers corresponding to each of the delivery mechanisms, each layer including a number of zones representing different levels of activity of the corresponding mechanism. Each zone is defined by a plurality of vertices, rather than on a pixel-by-pixel basis. The navigation controller receives satellite positioning data to combine with pseudorange correction data received from a fixed ground station to determine a corrected accurate global position of the vehicle. A graphics coprocessor includes active invisible graphics memory page onto which each layer is sequentially drawn and interrogated. One user selected layer can be stored on an inactive visible graphics memory page for visual display and then page flipped to the active page for subsequent interrogation. The pixel on each layer associated with the current global position of the vehicle is interrogated to determine the proper level of activity of the delivery mechanism at that location. The product delivery controller includes features to prevent re-application of a product on portions of the agricultural field over which the vehicle has already traveled.