In October of last year, the Canadian Avalanche Centre (CAC) issued a warning about the dangers of relying on smartphone apps that were being marketed as economical alternatives to avalanche transceivers. But a new smartphone app and add-on hardware component could provide an alternative that is not only cheaper than dedicated avalanche transceivers, but also provides additional functionality.

Unlike avalanche apps that rely on the Wi-Fi and Bluetooth signals emitted from a smartphone, as well as GPS, to help locate a buried avalanche victim, the Galileo-LawinenFon (lawinen is German for avalanche) system being developed by researchers from the Fraunhofer Institute for Material Flow and Logistics (IML) can provide greater accuracy thanks to a piece of hardware called Galileo-SmartLVS that connects to a smartphone via USB.

Packing a 3D magnetic field antenna for picking up signals, an analog-digital converter, a satellite navigation receiver, accelerometers and a reserve battery, the Galileo-SmartLVS turns a smartphone into an avalanche transceiver with the ability to draw on magnetic field signals and the combined signals of the USA's GPS, Europe's Galileo and Russia's GLONASS satellite positioning systems to pinpoint buried avalanche victims.

"Like commonly available avalanche transceivers, the Galileo-LawinenFon has a transmit and search mode," said Holger Schulz, a scientist at Fraunhofer IML. "Unlike previous transceivers however, when looking for victims the system is not restricted to the electromagnetic field formed by a transmitted signal but makes use of satellite signals as well. Since our solution draws on numerous available sensors and satellite systems, the signals transmitted by victims can be located with a great deal of precision. Magnetic field signals are processed in 3D so that we can pinpoint accident victims in a matter of seconds and improve their chances of survival."

Such pinpoint accuracy is a significant advantage over most basic devices that emit only an electromagnetic signal in "send" mode which then requires a search covering a semicircular area along the lines of this magnetic field to find the device. The technique to calculate the exact position of a buried person based on the signals captured by the Galileo-SmartLVS has already been patented by Fraunhofer and proTime, a company that partnered on the project along with Volmer Informationstechnik and the electrical engineering and IT department of Rosenheim University of Applied Sciences.

The system also includes the LawinenFon app that serves as the interface between the Galileo-SmartLVS hardware and the user. The app currently displays the distance and direction to the buried person on the smartphone screen, with the team planning to add the depth at which they are buried in the future. The device's reception range is currently limited to around 30 m (100 ft), but the researchers are working to extend this also.

"There is also the possibility of adding other useful functions to the app such as current snow and weather conditions," says Dipl.-Ing. Wolfgang Inninger, head of the IML project center. "These are extras that standard search devices simply don’t offer."

The researchers have successfully tested a prototype device that was able to locate a buried transceiver with centimeter accuracy and hope to have a commercial device on the market in the next two or three years.

Source: Fraunhofer