Optimization-Based Feedback Control for Pedestrian Evacuation From an Exit Corridor

The evacuation of pedestrians is the most important task when a building is subjected to a significant level of threat that compromises occupant safety. However, very few studies have dealt with the problem of controlling pedestrian evacuation in real time. Due to modern developments in sensor technology and computational facilities, it now seems possible to attempt a real-time controlled evacuation by instructing pedestrians to adjust their velocities according to an algorithm to effect an efficient evacuation. This paper deals with the development of such a control algorithm for an exit corridor where high congestion can be expected during evacuation. To accommodate the possible variation in the pedestrian density along the length, the corridor is divided into several sections. Using the conservation of pedestrian mass, ordinary differential equations that define the pedestrian flow in all sections are developed. For the system of state-space equations that define the flow in all the sections of the corridor, an optimization-based feedback control scheme is developed, which ensures the maximum input discharge subject to tracking the critical state and boundedness of the control variables. Simulation results are obtained, which indicate the superior performance of the controlled flow over the uncontrolled flow. The proposed flow control is also applicable to the regulation of vehicular traffic on a long section of a freeway in urban areas that receives input at several ramps along its length.