Evacuation time analysis and optimization for distributed emergency guiding based on wireless sensor networks

This paper proposes a load-balancing framework for emergency guiding based on wireless sensor networks. We design a load-balancing guiding scheme and derive an analytical model in order to reduce the total evacuation time of indoor people. The guiding scheme can provide the fastest path to an exit for people based on the evacuation time estimated by the analytical model. This is the first distributed solution which takes the corridor capacity and length, exit capacity, concurrent move, and people distribution into consideration for estimating evacuation time and planning escape paths. Through the proposed framework, the congestion of certain corridors and exits can be released to significantly reduce the total evacuation time. Analytical and simulation results show that our approach outperforms existing works, which can prevent people from following the local optimal guiding direction with the longer evacuation time in total. We also implement a prototype, called Load-balancing Emergency Guiding System (LEGS), which can compare evacuation time and guiding directions of existing schemes and ours under different people distribution.