This article appears in the July 2016 issue of Potato Grower.
“You’re turning my pivot into a sprayer.” This was the initial reaction from Terry Wilcox of Wilcox Fresh in Rexburg, Idaho, who incorporated the new ConstantDrive technology onto a part-circle Valley center pivot irrigating potatoes over extremely hilly ground.
“We are doing much more than that,” I responded, “we are converting your pivot into a ‘super pivot.’”
What defines a “super pivot”? Is it two to three times faster system speeds, fewer drivetrain component failures and system breakdowns; maintained momentum that mitigates getting stuck in the mud; improved wheel tracking; precise application and uniform distribution of water, fertilizer and chemicals including foliars; on-demand sector irrigation passes; elimination of spoking; soft starts that enable larger wheels, enhanced irrigation and energy efficiency? The answer is all of the above.
Under the veil of every mild-mannered start-stop drivetrain is a super pivot waiting to spring into action. Regardless of irrigation system brand or vintage or types of crops grown, patented ConstantDrive technology provides an affordable solution to the many mechanical complications and precision limitations that are the sole result of a legacy drivetrain.
The fact is that every new and existing electric-drive center pivot in operation today maintains speed and alignment by repeatedly cycling high-torque AC motors at full power on and off thousands of times per day. This technology has barely changed in the last half-century. With the advent of ConstantDrive, pivots’ worst days may be behind them.
With no change to a base pivot, sprinkler chart, irrigation schedule or even operation and control preferences, ConstantDrive enables a grower to double his pivots’ current top speed, to distribute water with the uniformity of rain, and to keep running throughout the entire season so that he doesn’t fall behind on his irrigation schedule. A grower can simply run his pivot as he normally does.
ConstantDrive utilizes a patented method of integrating analog alignment sensors with VFDs (variable frequency drives) to precisely control the output speed of each AC motor in order to maintain string-straight system alignment. A single VFD independently adjusts the center drive motor speed at each wheel tower and, if needed, a service switch allows the operator to manually select between VFD mode and start-stop mode as a failsafe backup for further prevention of irrigation system downtime. ConstantDrive is a disruptive innovation that completely eliminates the start-stop movement at every center pivot wheel tower to achieve faster, more efficient variable-speed irrigation.
Wilcox anticipates a 5 percent increase in Russet Burbank No. 1s just from the uniform distribution of water using ConstantDrive in combination with LESA (low elevation spray application) for mitigating wind drift. In this way, water is essentially being applied like a paintbrush. Improved distribution uniformity equals increased irrigation efficiency that, in turn, results in higher quality and yield.
“We believe in adapting technology to our farming practices,” said Boardman, Ore., grower Vern Frederickson, who is currently utilizing ConstantDrive with a Pierce center pivot on potatoes. “The technology brings many benefits: better uniformity, fewer gearbox and structure issues with our high-speed pivots, but most of all, better control of our chemical applications.”
For Frederickson, his pivot’s ability make a full revolution in three hours when applying chemicals helps to not only avoid wind and resume irrigation sooner, but to cut irrigation pumping time and costs in half during chemigation.
Grower Tyler Cranney of expressed a similar sentiment with regards to the ConstantDrive technology installed on a Zimmatic pivot irrigating potatoes near Oakley, Idaho. “The two biggest advantages that I see are uniform distribution and less wear and tear.” Cranney also foresees the elimination of spoking and runoff that result from the repetitive starting and stopping of spans to be a very big step.
Once ConstantDrive incorporates intelligence into every wheel tower, diagnostic data can wirelessly be sent to the cloud for predictive analytics; real-time preventative maintenance alerts can then be sent to the grower as the final step in virtually eliminating irrigation system downtime.
“Many herbicides and pesticides—especially those applied to control pathogens like various rots, molds and wilts—need to be applied such that the chemical stays on the leaves,” says Washington State University extension specialist Troy Peters. “A pivot that moves faster can apply less water and therefore results in a more concentrated chemical application that doesn’t run off the leaves. A faster pivot can apply chemicals in a manner closer to that of a sprayer, whose objective is to get the leaves wet, in contrast to an irrigation system whose objective is to get water into the soil.
“If an irrigation system is not uniform, then more water has to be applied everywhere in order to adequately irrigate all areas of the field,” Peters continues. “The start-stop movement of pipe spans presents a uniformity issue with high-speed center drives and irrigation systems with a small wetted radius like the newer, high-efficiency irrigation systems that many growers are adopting such as LESA.”
As for greater gearbox longevity and eliminating the added expense of special gearbox oils, Peters says, “When a gearbox stops, the oil drips off the gears, and then starting it again suddenly with less oil on it and a jerk creates a lot more wear than a gearbox that is constantly moving.”
The creators of ConstantDrive see it as only just the beginning of a much larger ag tech revolution centered at reinventing the way water, fertilizer and chemicals are applied to every field. As tools like ConstantDrive take the variability out of pivot irrigation, elimnating variability in the field is, conceivably, fully achievable with the application of sensor-based technology and big data.
Author Kevin Abts is the CEO at Irrovation, solutions provider of the patented ConstantDrive technology. He can be contacted by email at kevin@irrovation.com.
ConstantDrive is protected under U.S. patent 6,755,362 with other patents pending.