SQUED: A novel crowd-sourced system for detection and localization of unexpected events from smartphone-sensor data

In this paper, a Smart and Quick Unexpected-Event Detector, SQUED, is proposed to detect and localize unexpected events, such as traffic accidents, using crowd sourcing with smartphone devices. When users find an event, they point their smartphones in the direction of the event. SQUED can determine the location and the time of the event using global positioning system (GPS) and geomagnetic sensor data transferred from the built-in devices. In SQUED, a user doesn´t need to swipe or tap; he simply points the device. We developed SQUED on Android smartphones and evaluated our event-detection method in real-world settings. It was shown that SQUED can stably detect an event with high precision, even with noisy and fluctuating data for observed locations and directions.