Optimal observer-based pressure sensor placement for rigid sails

This paper investigates the optimal placement of pressure sensors for observer-based feedback on rigid domains, with a particular focus on rigid sails. Existing computational fluid dynamics (CFD) studies, supported by experimental validation, have shown promising results in analyzing sail aerodynamics using pressure sensors. Building on these developments, this study adapts the General Pressure Equation (GPE) into a linearized form, close to quasi-steady conditions, for pressure sensor placement analysis. Based on this model, an observer-based closed-loop strategy for optimal sensor placement is developed. A Lagrangian method is proposed to establish local optimality conditions in the infinite-dimensional setting without relying on reduced-order (lumped) models. The proposed strategy directly considers the state estimation efficiency within the optimal sensor placement process. The efficiency of the method to estimate the pressure field is illustrated by simulation results on a rigid sail with a symmetric profile and by experimental results on the jib (flexible) sail of a 6m sailboat.