Crowd monitoring ::critical situations prevention using smartphones and group detection

Festivals and big scale events are becoming more and more popular, they can attract thousands of spectators. Ensuring the safety of the crowd has become a top priority to many organisers after the multitude of dramatic accidents that resulted in losses in human lives. Monitoring the crowd via smartphones is a relatively new technique that emerged recently with the capabilities of mobile phones to transmit their GPS location data. We present a novel approach, based on the local crowd pressure, combined with the detection of groups in a crowd, to detect critical situations and propose evacuation plans that does not separate groups of people that are together. Groups were detected using DBSCAN clustering algorithm with 80 % accuracy. Location acquisition was tested during the Campus Fever event, and 87 % of the collected data had an accuracy lower than 10 m while 29 % of the total data had 5 m of accuracy. During 2 h of monitoring, activity of the application, reduced the battery of 20 %