This paper presents robust sensor fault reconstruction applied in real-time to an inverted pendulum. A linear observer is used to generate an estimate of the system states. Then the state estimates, inputs and outputs are used to generate a reconstruction of the fault. The observer was designed in order to make the reconstructions robust to system disturbances arising from mismatches between the linear model and actual system. Two design methods were tested; Bounded Real Lemma and Right Eigenstructure Assignment. Both methods produced excellent real-time results where the reconstruction is visually identical to the fault. (C) 2007 Elsevier Ltd. All rights reserved.