Abstract: A system for controlling the operation of a moving irrigation system lengthens the period of the on-and-off cycle specified by the speed timer to drive the pivot arm assembly. This reduces the frequency of the on-and-off cycles and thereby reduces wear and tear on the drive components. To modify the cycle period, a processor determines a modified on-time and a modified off-time having the same ratio of on-time to off-time as the speed timer to maintain the same average speed for the pivot arm assembly. The processor then controls operation of the pivot arm assembly to move in an on-and-off manner using the modified on-time and modified off-time.

Abstract: A method for controlling operation of a self-propelled irrigation system compensates for differences in expected wind drift and evaporative losses for time periods over the course of an irrigation cycle. Speed modifier values are determined for selected time periods to modify the base speed for the pivot arm assembly based on the corresponding expected wind drift and evaporative losses, with offsetting speed modifier values to modify the speed of the pivot arm assembly for other time periods, so that the period of time for completing an irrigation cycle remains unchanged. The pivot arm assembly is then controlled to move at the corresponding modified speed for each time period.

Abstract: A system for controlling the operation of a moving irrigation system lengthens the period of the on-and-off cycle specified by the speed timer to drive the pivot arm assembly. This reduces the frequency of the on-and-off cycles and thereby reduces wear and tear on the drive components. To modify the cycle period, a processor determines a modified on-time and a modified off-time having the same ratio of on-time to off-time as the speed timer to maintain the same average speed for the pivot arm assembly. The processor then controls operation of the pivot arm assembly to move in an on-and-off manner using the modified on-time and modified off-time.

Abstract: A method for controlling operation of a self-propelled irrigation system compensates for differences in expected wind drift and evaporative losses for time periods over the course of an irrigation cycle. Speed modifier values are determined for selected time periods to modify the base speed for the pivot arm assembly based on the corresponding expected wind drift and evaporative losses, with offsetting speed modifier values to modify the speed of the pivot arm assembly for other time periods, so that the period of time for completing an irrigation cycle remains unchanged. The pivot arm assembly is then controlled to move at the corresponding modified speed for each time period.

Abstract: A method of moving at least two irrigation spans across a ground surface of a field may include receiving an initial movement control signal corresponding to a user-selected fluid application rate, determining the user-selected fluid application rate from the initial movement control signal, determining a position of at least one span in the field, modifying the initial movement control signal to a modified movement control signal according to a predetermined modification factor, with a value of the modification factor varying according to a position of the span in the field such that the modification factor varies among span positions, and sending the modified movement control signal to the drive motor control. A system is also disclosed.