SmartGuide – A Smartphone Museum Guide with Ultrasound Control

While smartphones are well equipped for outdoor localization tasks, they usually do not provide support for identifying an indoor point of interest. This especially prohibits the context aware use of smartphones for guidance tasks inside a building, e. g. a museum. Alternatives like the use of near field communication (NFC) or barcode tagging demands an explicit interaction of the user with the tag, as well as dedicated sensors on the users’ phone. WiFi triangulation requires a calibration step for every distinct location. We found that ultrasonic signals, sent by a cheap, stand-alone emitter, can be the basis of a light-weight smartphone based proximity detection system. Using this technique we developed a prototypical context-aware museum guide and tested it successfully in public.