Date of Award


Document Type


Degree Name

Master of Science (MS)


Mechanical Engineering

First Advisor

Hamid R. Ossareh


The work presented in this thesis investigates and validates the dynamic modeling, fault detection, and fault identification (FDI) for the resistojet thruster system, typically used in low magnitude thrust applications for smaller spacecraft. The resistojet thruster is an improvement upon the widely utilized cold gas thruster, featuring an incorporated heating section aimed at improving propellant efficiency. This additional heating section enhances the performance of the system by increasing the propellant’s thermal energy before its discharge through the nozzle, subsequently leading to a reduction in overall fuel consumption. To implement a model-based FDI technique tailored to the typical resistojet thruster system, this research leverages the laws of conservation of mass, energy, and momentum, to develop a control-oriented dynamical model. This model serves as a fundamental framework for understanding the intricate operational dynamics of the resistojet thruster system. To ensure the accuracy and reliability of the thruster model, methods for tuning and validation are presented in this work. These methods are made possible by an extensive set of experimental data collected through collaborative efforts with industry partner, Benchmark Space Systems. In addition, main sources of discrepancy between the model output and the experimental data are identified and their effects are discussed. Building upon the insights gained from analysis of the experimental data, a suitable model-based FDI technique within the H∞ framework is selected from existing literature and tailored specifically to the intricacies of the resistojet thruster system. The effectiveness and efficiency of the chosen FDI methodology are thoroughly evaluated using both simulation-based studies and real-world experimental investigations. Notably, this research presents a rigorous Monte Carlo analysis as part of the simulation-based study, showcasing the robustness of the proposed FDI technique in accurately detecting and isolating prevalent faults while effectively preventing false positives due to uncertainties and disturbances inherent in the system.



Number of Pages

113 p.