Robot Mowers Take The Sweat Out Of Lawn Care

In the summer, the grass just grows and grows and grows. And that means people must mow and mow and mow.

But maybe not for long. Grass-cutting robots already exist, and more advanced ones are being developed by researchers who hope that robots may someday be helping out professional landscapers as well as trimming the turf at golf courses and athletic fields.

Small robots that can trim home lawns — at least average-sized ones that aren't on a steep hill — have been around for about a decade. Typically, the homeowner has to lay down a wire around the perimeter of the lawn. The robot moves around randomly within that boundary, taking off a bit of grass at a time while avoiding obstacles.

"The technology is here and it works," says Ames Tiedeman, vice president of the lawn and garden division at Systems Trading Corp. in New York, which distributes the Robomow brand of machines, made by a company called Friendly Robotics.

He says some models come with a kind of mini-garage so an owner can program the robot to come out at a certain time, mow for a while, then go back to its station to recharge its battery.

"You could program this to mow every other day, and you're done for the whole mowing season, once you set it up the first time," says Tiedeman.

Still Waiting To Catch On

So why don't more homeowners go for this kind of robot? "Well, that's a very good question," says Tiedeman. "I should say that we're growing every year. But you have to realize something: There is a class of people out there that actually like to mow the lawn."

One of them is Bob Markovich, home and yard editor for Consumer Reports. "Sometimes I'm cursing and saying, 'Boy, I wish I could do something else, I have to mow the lawn,' " says Markovich. "And yet I have to tell you, there's a certain peaceful solace in mowing the lawn."

Every year, Markovich and his team test dozens of lawn mowers, including, recently, a Robomow model and a LawnBott machine. "They really are more labor-intensive than you'd think," says Markovich. He says they can sometimes get stuck in places, for example.

And the grass isn't left with a pattern of straight lines. "They produce kind of an odd, random pattern," he says, "that some may not like."

Plus, these machines typically cost more than $1,000, way more than a regular push mower. "I think the short and simple answer is, it's still an expensive toy," says Markovich.

Sports Fields, Golf Courses Remain Primary Market

Sanjiv Singh, a researcher at Carnegie Mellon University's Robotics Institute in Pittsburgh, says that he uses an electric push mower to keep his small yard tidy — even though his day job involves developing new lawn-mowing robots.

The ones he is working on would be more powerful and sophisticated than anything you'd need for a simple home lawn, he says. Such machines could be attractive for businesses like sports fields, golf courses and professional landscapers, because these businesses have high labor costs and need to mow constantly.

"Those are serious players in the sense that they use their machines all the time," Singh says. "They would have the capacity to pay for a more expensive machine, and they're going to utilize it."

But something like a golf course needs consistent, precision mowing over large areas. To do that, the robot has to know where it is at all times, instead of moving randomly.

So over the past decade or so, Singh has been working on modifying professional-grade mowing machines so that they drive themselves, detect obstacles, and keep track of their location using GPS or other systems

"Technically, we were surprised to see how difficult it is to be able to generate a very repeatable kind of a pattern by the mower in sort of undulating terrain," explains Singh.

But after testing prototypes in places like Heinz Field, where the Pittsburgh Steelers play, he says automatic, precision mowing is technically doable. He is now working with a company, Sensible Machines, to try to make the technology more affordable so it can be commercialized.

"If we were to build a mower for $100,000, it would be able to cut the grass at most golf courses or most sports fields," Singh says, "but it would not have very good success commercially."

The Toro Co., a manufacturer of lawn mowers based in Bloomington, Minn., has been interested in Singh's work, giving him some support and equipment. Dana Lonn, managing director of Toro's Center for Advanced Turf Technology, says robot mowing is kind of at the toddler stage now. Still, he thinks it is coming — a matter of when, not if — and says it's a research priority for his company.

"You know, our products are getting more and more sophisticated all the time," says Lonn, pointing out that one of Toro's top-of-the-line products, the Groundsmaster 5900, already has "four microprocessors on it; it's got a network; it wirelessly reports how many hours it's achieved. Computers are driving it."

But — for now, at least — it still requires a human at the wheel.

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