Evolutionary Algorithms for Optimizing Emergency Exit Placement in Indoor Environments
Carlos Cotta, José E. Gallardo
TL;DR
This work tackles optimizing indoor emergency exit placement to enable rapid, orderly evacuations. It couples a cellular automaton (CA) model of pedestrian flow with two optimization methods: a greedy constructive heuristic and a real-valued Evolutionary Algorithm (EA), including an island-based variant (iEA). The objective $f(\sigma({\cal A},S))$ encodes a hierarchical evacuation goal that prioritizes minimizing $|\xi^-|$ before time $t_i$ or distance $d_i$, with normalization by the diagonal $D=\sqrt{w^2+h^2}$; exits are placed along the perimeter with a fixed width $\omega$ to minimize averaged evacuation performance across multiple scenarios. Experimental results indicate that the island-based EA generally yields the best solutions and outperforms the greedy method, although training data size influences overfitting and generalization to unseen cases. The study demonstrates the viability of global optimization for design decisions in safety-critical evacuations and highlights avenues for scalable, parallel simulations and surrogate-assisted methods.
Abstract
The problem of finding the optimal placement of emergency exits in an indoor environment to facilitate the rapid and orderly evacuation of crowds is addressed in this work. A cellular-automaton model is used to simulate the behavior of pedestrians in such scenarios, taking into account factors such as the environment, the pedestrians themselves, and the interactions among them. A metric is proposed to determine how successful or satisfactory an evacuation was. Subsequently, two metaheuristic algorithms, namely an iterated greedy heuristic and an evolutionary algorithm (EA) are proposed to solve the optimization problem. A comparative analysis shows that the proposed EA is able to find effective solutions for different scenarios, and that an island-based version of it outperforms the other two algorithms in terms of solution quality.
