GPS Swing Arms Prove Their Worth

When Boswell decided to add two corner systems to existing pivots nearly two years ago, he opted to go with the newest option from the manufacturer and install GPS-guidance on both. According to Boswell, who farms with the aid of eight center pivot units near Shickley, Nebraska, one of the corner arms was brand new. The other one was a used arm that came off a pivot that had been flipped by a windstorm leaving the corner arm as the only usable piece.

"I went with GPS on the new one, because it's on a rented farm where I didn't want to have to bury wire," Boswell explains of his investments. "The other GPS-guided arm runs beneath a high-voltage power line, which can interfere with the signal from the buried wire."

Just as GPS guidance has taken a role in equipment steering, it's also becoming the dominant force in corner pivot guidance. All four major pivot brands – Lindsay, Reinke, T-L, and Valley – now offer satellite-assisted corner guidance. Previously, the only option for corner system guidance was a wire buried in the ground that guided the steering arm via a radio signal.

"GPS guidance is still a little more costly option than the traditional buried-wire guidance system," says Neal Schlautman, engineering manager at T-L Irrigation. "Yet, nearly 95% of the new corner systems going out of here these days have the GPS option."

Schlautman says wire guidance is still a viable option on farms with deep soils that are owned by the customer. However, he says GPS corner systems have become especially appealing to customers who buy a system to erect on a rented or leased farm, since they don't lose the investment in guidance if they lose the lease.

accommodates future expansion

Another exammple where GPS might be the preferable choice would be a field that has an old farmstead in one corner that you hope to take out someday, Schlautman says.

"Rather than splice in a new section of wire when that day comes, all you have to do with our GPS navigation is to use the teach function to create a new path," he says.

Schlautman says GPS guidance on center pivots has also opened up a world of new opportunities in fields that have traditionally been too rough or too rocky for buried wire.

In the meantime, guidance has only gotten more accurate since the first GPS corner guidance systems were introduced a few years ago.

rtk guidance

Today, GPS corner systems from all four brands use signals from multiple satellites to avoid losing a signal.
All four brands also employ real-time kinematic (RTK) guidance, which is either supported by multiple brands of existing receivers utilizing an existing base station or an irrigation company-supplied base station, which requires no subscription.

"Our systems also include a wheel-angle sensor that helps ensure track-on-track accuracy," Schlautman says. "We can retrofit GPS guidance onto older corner systems, too."

However, retrofitting is more expensive than if it were purchased with a complete new corner arm system, simply because the customer is bearing the full cost at the time, he says.

"In other words, we're not shipping a system with GPS guidance in lieu of wire guidance and crediting you for part of the cost," Schlautman explains.