Sit back and let the tractor do the steering

Wednesday, August 10, 2011

Manufacturers have yet to provide tractors that drive themselves, but that day may not be so far off

by MIKE MULHERN

In the not-too-distant future, scientists predict that farm robots will plant, spray and even hand-pick crops. But, for now, the best we can do is sit back and let the tractor do the steering while another program measures out the seed, spray or fertilizer.

Global Positioning Systems, or GPS, have enabled precision farming in the 21st century. By guiding us over our fields, GPS keeps lines straight and eliminates overlap, which can cost time and money.

When farmers work their fields with implements that can stretch to 60 feet, GPS tracking can keep each line accurate to within centimetres. You don't even have to steer. When you get to the headlands, depending on the system you have, you can either make the turn or allow the computer to command the implement lift, the turn and re-engagement, all at the press of a button. If your tractor doesn't have GPS steering, you go back to the manufacturer or buy an after-market brand that will adapt to any tractor. If it has power steering, a retrofit is possible.

One of the big after-market players is Hemisphere GPS, which features the Outback brand. Ryan Warehime, senior marketing co-ordinator for Hemisphere, says they can adapt to any tractor and their systems, beginning at about $900 for simple light-bar guidance, go all the way to something called eDriveX, which will cost about $20,000 all in but it does a lot.

"eDriveX is proportional steering that gets you down to about two centimetres of accuracy," Warehime says. "It will steer straight contour lines and then, at the end of the field, it actually has auto turn."

To accomplish the turn, the operator has to respond to a beep and screen prompt and tell the machine whether to turn left or right. "It gets you back on a straight line faster than you could turn yourself," Warehime says. "It does a perfect turn."

Installation, he says, can usually be accomplished by the farmer. It is especially easy if the manufacturer has included a harness you can plug into.

One of the manufacturers offering an optional, factory-installed, auto steer system is John Deere. Its system is a drive-by-wire one similar to that being offered on high-end automobiles. John Deere senior product development marketing representative Aaron Bartholomay says drive-by-wire is relatively new to the industry.

"Now, rather than having a mechanical linkage from the steering wheel down to the hydraulic valve," he says, "there are input sensors on the steering wheel and, as you turn the steering wheel, that's what commands the steering." Bartholomay says drive-by-wire also allows them to vary the steering ratio, depending on whether you are in high-speed transport mode or driving slowly over the field.

While John Deere has been offering GPS systems since the early 1990s, the latest systems on 2011 model 8R tractors are the most advanced, allowing the machine to auto-steer along a line and turn at the end of the field. "It will raise the implement up, turn the tractor at the end of the field, and then automatically send it down the field on its next path," Bartholomay says.

John Deere also offers a type of OnStar system called JDLink which gives location, machine functions and productivity and performance data, which is fed to John Deere. Owners can access the information and remotely monitor their machines through a website.

AGCO technical marketing specialist Marlin Melander says his company offers GPS systems, along with ISO terminals that control whatever the tractor is pulling.

"Let's say you have a Massey Ferguson tractor and you have a White planter, both products that we manufacture. That Massey Ferguson tractor has an ISO console in it. The White planter will plug into the back of the tractor on the electronic side and then control of that planter – seed rates, row shutoff and that type of thing – will be done through the console in the cab that comes from the factory." 

He says systems that steer and track do not come standard from the factory, but they can be ordered with the machine as an option.

"If a customer is ordering up a tractor, they can have satellite guidance systems built into it from the factory, but it doesn't come standard," Melander says. "We still allow them the option of purchasing the tractor without having that extra expense if they don't feel they need it." He adds that they are seeing a "high rate" of tractors being ordered that are auto-steering ready.

Case New Holland precision farming specialist Jim Jewsbury says they have a full line of auto-guidance, flow and application and control functions.

"Some of the tractors come full auto-guidance complete," he says, "and other tractors come guidance-ready." While their systems guide and steer tractors along the row, they do not turn at the end of the row.

"Our systems demand that the customer take control at the headland or at the end of the row," he says. All their products "have the ability to have some sort of auto-guidance installed on them. Some come ready. You plug in the electronic components on the top side; the hydraulic components are already installed and the balance are platforms that you can connect to and end up with an auto-guidance system."

While they have been offering guidance systems for about 10 years, he notes that the technology is advancing rapidly.

"Flow and application control is going to be a strong focus for New Holland going forward," he says, adding that their systems can also be hooked up to other product lines to work with New Holland equipment.

None of the manufacturers is offering tractors that drive themselves yet, but the coming robotic age will offer that and much more. In a recent article in Discovery News, scientists talked about teaching computers to see like humans and to get better at their jobs as they work and learn.

"The technology is ready now and we can start seeing this penetrating into the market," says Yael Edan, an engineer and robotics researcher at Ben-Gurion University of the Negrev in Israel. "I would say there will definitely be robots out there in five years." BF