Introducing the Robot Lawn Mower

Don't worry about cutting your grass anymore, let the iRobot do the job for you. For more than a decade, iRobot, the company behind the Roomba vacuumbot, has been working — and working — on robotic lawn mowers. Now it finally has something to show for the effort, though it's come at a cost.
Also: Tips to Read Before Buying a Robotic Vacuum Cleaner

The flat square autonomous grass-cutter that Angle's company unveiled Wednesday resulted from a protracted engineering struggle that included dead-end experiments and a conflict with radio astronomers.

Engineers threw every technology and mechanical design they could at the secret project, which they hid behind tall, opaque fences abutting a freeway just outside iRobot's Massachusetts headquarters. The test lawn included a picnic table and other obstacles.

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Also ineffective was the sophisticated computer vision that powers the latest Roombas. The technology didn't work well outside because camera lenses can get blocked by leaves or dirt, and its machine-learning algorithms get confused as the mower bumps up and down. Laser range-finders and ground-based beacons presented different challenges.

Ultimately, though, financial pressure on the robot maker to diversify its product lineup raised the stakes. (After spinning off its defense robotics division in 2016, iRobot is almost exclusively a seller of vacuums. The main exception is the Braava robotic mop, which accounts for a fraction of total revenue.)

Robotic lawn mowers also started to proliferate in Europe, where they're now a roughly $300 million industry. Those robo-mowers, however, require homeowners to set up a perimeter of boundary wires to keep the machines in a confined area.

The company finally found its answer in a radio technology based on "ultra-wide" bandwidths that would guide the mowers with the help of beacons situated around the lawn, combined with the map-making memory that iRobot already uses for its vacuums. But that idea ran afoul of astronomers who said the radio signals could interfere with their studies of interstellar chemistry.

IRobot eventually won permission from the Federal Communication Commission to use ultra-wide bandwidth for wireless robotic lawn mowers — though not before Harvey Liszt, spectrum manager for the National Radio Astronomy Observatory, argued to the FCC that "there is already a competitive market for robotic lawn mowers using wire loops, which has somehow failed to stanch the stream of ghastly accidents and split gasoline that iRobot associates with the mundane practice of lawn-mowing."