In "Shape Recognition of Metallic Landmark and its Application to Self-Position Estimation for Mobile Robot," (a paper in Journal of Robotics and Mechatronics,) Tokyo robotics researchers Hajime Fujii, Yoshinobu Ando, Takashi Yoshimi,
and Makoto Mizukawa, propose to encode location information in the shape of the surface of manhole covers as a source of location data for confused robots:
So say Hajime Fujii and colleagues from Shibaura Institute of Technology in Tokyo, who have worked out that manhole covers are amongst the more permanent of objects in our built environment. And better still, they point out, they are made of metal – and so are easily detectable by a simple metal detecting scanner.
In the latest edition of the Journal of Robotics and Mechatronics, they reveal how the shape of each manhole cover in a locale can be used to give a robot a position fix.
Why bother? Its critical to check your calculated position every now and then against a known GPS position – because robot wheels can slip (their rotations are counted to give position estimates) or a robot's leg stride can be miscalculated, leaving dead reckoning dead in the water.
But GPS, the researchers complain, cannot be received well in downtown concrete canyons. And cameras that compare buildings with Google Street View style databases are no good when the light is fading.
(via Beyond the Beyond)