You know how long it's been since we first heard that iRobot's making a robotic lawn mower? Nine years. After almost a decade of wondering if we'll ever see Roomba's more outdoorsy sibling, iRobot's finally giving us a glimpse of how the device will work through an FCC filing. Other robot lawn mowers require you to prep your lawn by burying wires around the perimeter -- the machines will recognize those wires and won't venture beyond them. iRobot, however, plans to use a wireless beacon system that entails burying four to nine beacons to mark the edges of your lawn. Those beacons will calculate the robots' position within the property and transmit it to the machine.