International audienceThis paper addresses a method for robust fault detection and estimation by minimizing the disturbance and uncertainties to residual sensitivity. It consists in the design of proportional integral observer while minimizing the well known H ∞ norm for worst case uncertainties and disturbance attenuation, and combining a transient response specification. This multi-objective problem is formulated as linear matrix inequalities (LMI) feasibility problem in which a cost function is minimized subject to LMI constraints. This approach is employed to generate a set of robust observers for uncertain switched systems