Design and development of an experimental test bench for the study of small-scale electric propulsion systems

As the aviation industry shifts towards the more electric aircraft concept (MEA), the demand for reliable, efficient and small electric motors continues to grow. This thesis presents the design, development and testing of a sensorized modular test bench for the analysis of these motors, particularly in the context of small-scale propulsion and electro-mechanical actuation. The test bench incorporates fiber optic based sensors to capture real-time data on temperature, torque, and vibration. In particular, Fiber Bragg Grating (FBG) sensors were adopted because of their very small footprint. This compact size allows the sensors to be retrofitted into existing components or seamlessly integrated into new designs, two different approaches which were effectively applied in this work, respectively for the motor and relative mount sensorization. Additionally, the test bench was designed to include an easily adjustable artificial load, generated by coupling a separate electric motor connected to a rheostat. Particular care was taken in the design and production of a dedicated compact and modular vibration sensor, which was then installed and tested on the bench. Once all of the design, construction and sensor integration phases were completed, calibration runs were conducted to correlate throttle levels and rotational speed. Lastly, structured tests were carried out across multiple throttle settings. Using data collected during these runs, the relationship between throttle input and thermal/mechanical performance was analyzed, exploring the potential for advanced health monitoring and virtual sensing methods. Experimental results indicate a link between throttle levels, thermal behavior and vibration power spectrum, demonstrating how sensor integration can support advanced diagnostics and predictive maintenance strategies for electric motors in aerospace applications. Additionally, the test bench proved to be an effective platform for further research and development of advanced sensor integration solutions, as well as virtual sensing and health monitoring algorithms. One of such possible further innovations is the real-time estimation of electrical parameters using only thermal and vibration data, along with an analytical model of the system.