9 July 2012
The Earth’s magnetic field once helped pioneering explorers discover exciting new lands and untold riches. Now, it could stop you getting lost at the shops, thanks to an upcoming smartphone app that uses magnetic fluctuations to map indoor locations, guiding you around places that GPS can’t penetrate.
It has been developed by a company called IndoorAtlas, which was spun out of the University of Oulu in Finland by computer scientist Janne Haverinen and colleagues. In 2009 Haverinen told New Scientist how he built a robot that could navigate by magnetic fields after reading about a lobster with a similar ability. Now he’s taking advantage of the digital compasses found in modern smartphones to do the same for people.
Compasses don’t normally work inside buildings because metallic structures disturb the Earth’s magnetic field, making it impossible to reliably find north, so IndoorAtlas takes a different approach by using these disturbances to create a unique map within each building. Map makers simply have to align their building’s blueprint with a traditional map, then wander along designated paths with smartphone in hand to chart the magnetic variations.
Visitors to the building can then download the map to their own phone and navigate as normal, though users do have to travel a distance of 3-5 metres before the system locks on to their location. It might be worth the short wait though – unlike other proposed indoor navigations systems based on Wi-Fi and Bluetooth, IndoorAtlas doesn’t require any additional infrastructure, making it suitable for locations that suffer from radio interference while also reducing maintenance costs.