The technology is decades old, but it’s hard not to marvel at some of the ways GPS is being used today. Besides giving people near-precise driving directions and telling hikers how far …
The technology is decades old, but it’s hard not to marvel at some of the ways GPS is being used today. Besides giving people near-precise driving directions and telling hikers how far they’ve walked up a trail, we can see in real time where the delivery driver is with your pizza.
People don’t always see how the technology is being used in agriculture, but it’s just as impressive.
Working on razor-thin margins, farmers are benefiting from the way precision GPS, combined with GIS mapping, lowers their inputs and maximizes crop yields. The technology can provide less water on an area where it puddles too much, plant more seeds on a spot that’s particularly fertile, or leave off fertilizer on soil that’s got too much bentonite and won’t grow anything. That’s on top of driving the machinery exactly where it needs to go over the field.
However, it requires something much more precise than what we use in our cars. The signal on your smartphone is accurate to about 16 feet, which is “plenty accurate for driving and hiking — things like that,” said Greg Wilson, general manager for Heart Mountain Equipment.
The business is the authorized dealer of Trimble equipment, which specializes in precision farming.
Buildings, trees, map defects, and other obstacles can degrade the accuracy of the signal, which is why GPS can sometimes send you driving over houses next to the road.
Unlike the GPS on your car, however, utilizing GPS technology in agriculture requires a lot more precise measurements than a one-signal GPS unit can provide. In modern agriculture, farmers need to be precise down to less than an inch, and that requires something much more complex than your car uses.
At one time, GPS satellites degraded the signal — known as selective availability (SA) — so that civilian users wouldn’t have the accuracy the military does. After a long political battle over concerns that it would undermine national security, in 2000, the government agreed to stop degrading the civilian signal. The newest GPS satellites going into space no longer have SA capability.
New civilian signals are being phased in, and there are some augmentation systems that are used to improve GPS accuracy. Some of these were developed for aviation, but they are also used in agriculture.
Even with these augmentation systems, it’s not quite accurate enough for agriculture. To really get down to that sub-inch level, they use a locally based system called real-time kinematic (RTK).
This system uses a fixed position — in the case of Powell-area farmers, this base station is on the Big Horn Co-op building near Hamilton and South streets — to adjust data gathered from a number of GPS satellites to adjust for variations and arrive at a precise data point that can be accurate within a centimeter.
“You can drive a tractor over snow and come back, and you can’t see any change in the tracks. It’s exactly in the same spot,” Wilson said.
In older tractors with retrofitted computer equipment, worn bushings, pumps, and cylinders might not get that perfect track the way a new tractor would, but the RTK signal can provide the steering inputs needed to do it if the equipment is good enough, he said.
Wilson said the technology is also being used to upgrade the area’s tile drain systems, which were put in as much as a century ago to direct the runoff irrigation on fields back to the river. Sometimes these old terracotta drain routes direct water into the basements of new development or become so clogged that they fail to properly drain fields. The RTK signals help ensure a very precise grade of the drains’ slope under the soil. It can also help grade the field so flood irrigation rows water more evenly.
While some crops don’t need such precision, Wilson said most farmers are adopting these technologies to get the most out of their operations. While there was some reluctance among some of them a couple decades ago when it was first coming into use in the area, as it is with any technology, precision farming is becoming the norm.
“I’m old enough to remember when some people said they wouldn’t ever have an automatic transmission. Now, it’s hard to find a standard transmission on a new car,” Wilson said. “We’re seeing the same thing with farm technology.”
The tractors still need a human operator on board, just like self-driving cars. As precise as the technology is, errors can still drive a $500,000 piece of equipment into a ditch or onto a highway. However, Wilson said, he’s seen robotic, self-driving tractor concepts displayed at industry conventions. In the future, the farmer might complete his whole harvest from his home office.