Estimation of a gaseous release into the atmosphere using a formation of UAVs

The real-time estimation of a gaseous plume that results from gas released into the atmosphere by a moving aerial source is presented. The approach is utilizing a group of UAVs equipped with gas concentration sensors onboard and the concentration measurements are used in an estimation scheme in the form of a Luenberger observer. The estimator is modeled as the advection-diffusion equation, which is solved numerically in real-time using a finite volume method on a dynamically adapted computational grid. The UAVs maintain a rigid flying formation, with the control signals for the leader being provided by the Lyapunov-redesign method, which couples the UAV dynamics to the performance of the estimator. The follower UAVs provide plant information to the estimator and also compute the spatial gradients necessary for the implementation of the guidance scheme. Numerical examples illustrate the performance of the proposed approach.