May 23, 2007 | By: Laura Skillman

Technology has advanced at a rapid pace on the farm, from satellites guiding farmers through their fields to equipment allowing a tractor to steer itself.

“We’re really at an exciting time with this technology,” said Ben Koostra, an engineer associate with the University of Kentucky College of Agriculture. “What we’ve seen is in the past five or six years, the very early adopters started using this technology,” he said. “But in just the last few years we’ve seen more and more people starting to use this stuff.”

Farmers use global positioning satellites to pinpoint field locations for such activities as soil testing, field mapping and crop yield monitoring. This technology allows anyone with a GPS receiver to determine their location based on latitude and longitude as well as elevation.

The GPS system can also be tied to a light bar with the ultimate goal to reduce overlaps and skips in fields. A light bar inside a tractor guides equipment through the field from pass to pass. If the driver gets off the path, the light bar shows the necessary adjustments. Light bars have proven to pay for themselves, Koostra noted during the recent UK wheat field day.

The technology has improved, Koostra remarked, with systems today able to account for curves and slopes while earlier versions only allowed for straight line use. Few fields, especially in Kentucky, are perfectly straight, he noted.

Auto steering is something that is also gaining popularity with farmers as the technology and quality of the equipment has improved, he said. Auto steering basically takes the task of steering the tractor away from the farmer. Instead, GPS technology guides the tractor through the field.

There are two main types of systems. One is a motor that attaches to the steering column and the other is an integrated hydraulic controller which taps into the hydraulics of the steering system. In both cases the computer automatically steers the tractor.

“We are seeing entry-level auto steer systems quite a bit with operations like spraying where you don’t have to be ultra precise,” he said. 

Technology systems have different accuracy levels and costs. Farmers need to do their research to determine the type of GPS system they will need to perform specific tasks. Low cost 
receivers on the market are accurate within three meters. As the price increases, so does the accuracy. The highest accuracy level can be within an inch, but can cost tens of thousands of dollars.

This technology uses real time kinematic receivers or base stations and uses radios to transmit information to field equipment, Koostra said. Some companies and even farmers are developing base station networks within a geographic area with some people owning base stations and others paying a fee to use them.
New technology is now also putting GPS systems onto the implement to ensure that it is tracking in the same path as the tractor. This technology will ensure accuracy on sloped fields where the implement may move at a slightly different angle than the tractor. This is important in central Kentucky because of the terrain, he said.

Individual row or spray nozzle control is also being developed to account for turns in fields to eliminate over application or under application or seed placement.

Farmers may view a planter with individual row controls at this year’s UK field day on July 26 at the Research and Education Center in Princeton. Field day participants also will be able to see demonstrations of a tractor equipped with both types of auto steer technology.


Ben Koostra, 859-257-3000, ext. 121