ROBOTS don鈥檛 speak English or understand hand signals, so how do you tell one where to go? Researchers at the University of Missouri, Columbia, have found an answer: show it sketches.
Marjorie Skubic and her colleagues have been using a personal digital assistant (PDA) to sketch out the kind of directions you might give a friend, which they then beam to a domestic robot. She has been running experiments to see how well a robot can follow a rough sketch around a room full of filing cabinets, tables and chairs.
鈥淚t鈥檚 already succeeding in 50 per cent of routes,鈥� says Skubic. The system, which will be presented at the IEEE conference on Robotics and Automation in New Orleans later this month, is still in the early stages of development. Eventually, Skubic hopes, it will remove one of the major obstacles to people using robots in their homes.
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One the problems with domestic robots so far has been how to give them directions. For example, the Roomba robotic vacuum cleaner, made by iRobot of Burlington, Massachusetts, doesn鈥檛 even try to tackle this problem. Instead it is pre-programmed with its own rules for covering the floor space, but this means it vacuums wherever it wants to, not where you want it to. 鈥淵ou can鈥檛 tell a Roomba where you want it to go like you can someone cleaning your house,鈥� concedes Colin Angle, iRobot鈥檚 co-founder and president.
But what if you did want to tell it to follow a specific route? After looking at psychological research and studying how people communicate routes, Skubic found that most people preferred to do this by following sketched maps that show landmarks along the route. Crucially, they do not pay close attention to angles or distances. 鈥淥n a sketch it may be a 90-degree turn but all you really need to know is you make a major right turn,鈥� says Skubic.
So Skubic鈥檚 student George Chronis wrote software that can extract the configuration of landmarks from a rough sketch, and turn them into directions. To direct the robot, you sketch a rough route out on the PDA, marking landmarks such as desks or cupboards as closed polygons (See Diagram). The sketch is then beamed over a Wi-Fi wireless link to a server, which analyses it and produces a set of instructions for the robot. The server then beams the instructions to a Nomad 200 robot that has been modified to be able to combine the information it receives from the server with a sonar map of its surroundings that it produces for itself.
To work out which way to move, the robot looks for features in the sonar landscape and matches them with the information from the server. Some trials failed when the robot mistook parts of distant walls for landmarks. To prevent this, Skubic plans to combine the robot鈥檚 sonar with a camera and object-recognition system to help it tell the difference.
Angle says Skubic鈥檚 system could be adapted to tell the Roomba to avoid certain parts of the room. But he believes it would be a bad idea to tell it how to clean: it鈥檚 best left to its own devices, he says.
