Oregon police responded to a burglary call only to find a Roomba® causing ruckus in a bathroom, according to NPR. A concerned house guest called the police due to strange noises coming from a locked bathroom, but when law enforcement got in, they found a robot vacuum moving back and forth across the floor. The development of robotic vacuum cleaners has come a long way.
Three deputies, a detective, and two canine officers responded to the burglary call, NPR said. The officers were concerned when they identified themselves and the “burglar” failed to respond—a concern that was compounded when they announced they had two canine units with them. The house guest had said he’d seen shadows moving under the door to the bathroom, and when police opened the door they found a Roomba trapped inside. Everyone involved had a good laugh at the mishap, but the rogue vacuum’s misadventure happened amidst surprisingly advanced home robot technology.
A Brief History of the Roomba
In 2001, Electrolux became the first company to sell a robotic vacuum cleaner to the public. MIT-based robotics company iRobot followed suit in 2002 with the first-generation Roomba, which saw far greater success. “Roombas were the “Model T” of robots—the affordable and reliable machine for personal use that transforms lives,” said Dr. John Long, Professor of Biology and Professor of Cognitive Science on the John Guy Vassar Chair of Natural History at Vassar College. “One of the really important design features is that Roomba goes where you don’t see or normally go—under the furniture.”
Future generations of the Roomba added features like measuring the size of a room, cleaning on a schedule, and self-docking at a charging station when batteries run low. The robotics company, iRobot Corporation, an American advanced technology company founded by three members of MIT’s Artificial Intelligence Lab who had experience in designing robots for space exploration and military defense, developed a line of iRobot® vacuum cleaners. iRobot introduced the Scooba®, which vacuums and scrubs floors; and the Braava®, which performs both dry and damp mopping. However, Roombas and Scoobas have both been traditionally round for ease of navigation, while Braava is clearly square-shaped. These differences bring up a major component of home robotics: trade-offs in functionality.
Roomba – Efficiency vs. Robustness
Roombas and Scoobas operate on behavior-based control systems. “To make sure that most areas [of the floor] are covered, Roomba and Scooba are programmed to make multiple passes,” Dr. Long said. “That takes more time, more battery power, and that’s where the inefficiencies come into play. Thus, the trade-off for behavior-based cleaning is simplicity and robustness versus efficiency.” The mass market noticed this inefficiency and many customers stated that they preferred a robot that could clean the floor in one pass. To do this requires a robot that uses a map-based navigation system rather than Roomba’s navigational system, which counts the number of its own wheel rotations to learn the size and shape of a room.
Unfortunately, GPS is too inaccurate for indoor use. Instead, “Braava works using this totally cool thing called an infrared navigation system, which they call NorthStar,” Dr. Long said. “The NorthStar system uses a beacon, the NorthStar® Navigation Cube, that sits on a table and projects IR dots onto the ceiling. Braava uses three infrared sensors to detect its distance from those dots and then triangulates its position.” Dr. Long explained that Braava uses this to make a map of the room and move in tight rows to clean the floor in a single pass.
This can often help Braava avoid getting stuck in a tight space like the Roomba in Oregon, as well as be more efficient, but this model-based navigation sacrifices maneuverability to do so, as well as a degree of autonomy. “Braava has to have a good signal from the NorthStar IR navigation system in order to clean your whole space,” Dr. Long said. “Where you get into trouble is if you have angled ceilings and ceiling fans that can interfere with the navigation signal, as can plasma televisions and fluorescent lighting—both of which emit infrared light.”
Despite hiccups like Scooba’s three-pass cleaning system, Braava’s dependence on a flat-ceiling IR signal, and the Roomba burglar of Oregon, home robotics is advancing at a considerable rate. As the wrinkles are ironed out in the near future, the field has plenty of potential.
Dr. John Long contributed to this article. Dr. Long is a Professor of Biology and a Professor of Cognitive Science on the John Guy Vassar Chair of Natural History at Vassar College. He also serves as the Director of Vassar’s Interdisciplinary Robotics Research Laboratory, which he helped found in 2003. Professor Long received his Ph.D. in Zoology from Duke University.