Comparison of Three Approaches to Atmospheric Source Localization

Abstract

The paper describes three methods for finding the source of an airborne contaminant in a turbulent wind field. We assume that an unmanned aircraft samples the atmosphere at a constant altitude within the planetary boundary layer, measuring the contaminant concentration. The turbulent wind field is generated using the openly available software TurbSim. A concentration field, or plume, is created by advection and diffusion of the contaminant from its source. The plume is modeled using a filament-based method proposed in the literature. The unmanned aircraft is assumed to sample the concentration field quickly, relative to the plume dynamics; once the plume has matured, the concentration is fixed and the sampling strategy is executed. A recursive Bayesian estimation approach is compared with a gradient descent algorithm and an extended Kalman filter. By comparison, Bayesian estimation requires relatively weak modeling assumptions, and simulation results suggest this approach is less sensitive to error in the...