Patent ID: 8924101

Claim:
A method of controlling movement of an irrigation system in a field based upon at least one transient condition in the field, the irrigation system including a span movable over the field, the span being supported by a plurality of towers, at least one of the towers having at least one wheel resting on the ground surface of the field and being rotatable to advance the span across the field, at least one of the towers having a motor assembly to rotate the wheel of the tower, the method comprising: providing a remote control unit on the irrigation system, the remote control unit including a location determination assembly configured to determine a location of the remote control unit on the span at a time; receiving a selected fluid application rate by the remote control unit; detecting an initial location of the remote control unit by the location determination assembly; determining an expected distance of movement of the remote control unit over at least one time interval at an initial movement speed, moving the span for a time interval in a manner corresponding to the selected fluid application rate; at an end of the time interval, detecting a first intermediate location of the remote control unit by the location determination assembly; determining an actual distance of movement during said time interval based upon the initial location and the first intermediate location; comparing the actual distance of movement to the expected distance of movement; determining if there is a deviation between the actual distance of movement and the expected distance of movement, and if a deviation exists, then determining a magnitude of the deviation; and if there is a deviation, then calculating an adjusted movement speed for a subsequent time interval.