FallAlarm: Smart Phone Based Fall Detecting and Positioning System

This paper presents a system called FallAlarm, which is utilized for fall detecting and positioning using a smart phone. A tri-axial accelerometer sensor and a Wi-Fi module embeded in the phone are employed to provide needed information. Data from the accelerometer is evaluated with a decision tree model to determine a fall. If a fall is suspected, a notification is raised to require the user's response. If the user is injured hardly and cannot respond in time, the system immediately begin to position the occurence of the fall event by detected surrounding Wi-Fi signals, then automatically send a alarm message to his pre-specified guardian with a message via SMS(Short Message System). Consequently, the victim of fall can be monitored and cared in real time. Tested on a real-world data set, the FallAlarm system can achieve an acceptable accuracy for practical application.