Abstract: An apparatus may include a reservoir configured to hold a fluid additive, an injector element to inject the fluid additive into the primary fluid applied to a ground surface by the irrigation apparatus, a flow sensor to measure the flow of the fluid additive from the reservoir to the injector element, and a pump apparatus controller configured to maintain a rate of pumping of the fluid additive based on the output of the flow sensor. The additive pumping apparatus configured to vary a pump motor speed and thereby the rate at which the fluid additive may be pumped into the primary fluid of the fluid application assembly, the adjustment to the pumping rate being based upon the current position and the actual speed of movement of the distal-end of the outermost span of the irrigation apparatus in the field.

Abstract: A method and apparatus for site-specific application of a fluid additive, with or without irrigation water, wherein a center pivot or lateral move irrigation system is utilized for a dedicated additive spraying system. Said spraying system including an additive pumping apparatus with a pump controller in communication with an irrigation system position sensor, and an additive pump in fluid communication with a reservoir of additive and a plurality of flow control valves. Said flow control valves each in fluid communication with an additive carrying conduit, said conduit terminating with an end-portion of conduit with spray nozzle set. Each said end-portion with spray nozzle set configured to apply additive to a ground surface below said end-portion and within the boundaries of polygon shaped areas of a field based on the position of the pipe spans, said position provided to the pump controller by the irrigation system position sensor.

Abstract: An irrigation system with steady state speeds of movement achieves and maintains substantial straight alignment of multiple interconnected spans with continuous movement over a range of speeds in a forward and reverse movement direction. A variable-speed drive controller monitors and processes the output of the corresponding alignment detector and, based on the output of the alignment detector, selects from memory and continuously furnishes to the corresponding span motor a predetermined progressively increasing speed profile, a predetermined progressively decreasing speed profile, or a new fixed current speed.

Abstract: An irrigation system with transient state speeds of movement achieves and maintains substantial straight alignment of multiple interconnected spans with continuous movement over a range of speeds in a forward and reverse movement direction. A variable-speed drive controller monitors and processes the output of the corresponding alignment detector and, based on the output of the alignment detector, selects from memory and continuously furnishes to the corresponding span motor a predetermined progressively increasing speed profile or a predetermined progressively decreasing speed profile.

Abstract: An irrigation system with an alignment detector uses a plurality of discrete sensors to detect and measure each irrigator span's misalignment when moving in either direction. In particular, this sensor alignment detector utilizes a first sensor for the forward movement direction and a second sensor for the reverse movement direction, which provides a significant improvement in alignment optimization and sensitivity.