Design and Development of an Electromechanical Actuator Test Bench for Validation of Health Monitoring Models

Electromechanical Actuators (EMAs) for aircraft flight controls are progressively replacing hydraulic systems in safety-critical applications. Hence, simple and accurate EMA numerical models are required for the real-time health monitoring of such equipment, as well as more detailed and computationally intensive simulations for design and training of machine learning surrogates. In order to validate these models, we developed a dedicated EMA test bench (Figure 1) intended to replicate the operating condition experienced by common flight control actuators. The bench is highly modular, allowing to easily replace components and test different EMA architectures. In order to contain costs and time associated to the development, we made extensive use of off-the-shelf hardware; most of the custom designed parts were manufactured through rapid prototyping techniques. The test bench is able to simulate the operation of the actuator in nominal conditions and in presence of incipient mechanical faults, namely a variation of friction and an increase of backlash in the reduction gearbox. Sensitivity to electrical fault modes will be included in a future upgrade. The output of the test bench was compared to the predictions of numerical models in nominal conditions. The results showed a good matching between the two systems, which is promising for the use of such models within real-time health monitoring routines.