Electro-mechanical actuator for helicopter landing gear extension/retraction: experimental study and dynamic model validation

This work summarizes the testing and simulation activities carried out for the study of an Electro-Mechanical Actuator (EMA) for helicopter landing gear extension/retraction. The basic objective was to obtain an experimentally-validated model of the EMA dynamics, to be used as support tool for the design enhancement and for the development of similar systems. The database for the model validation has been obtained by testing the EMA with a real-time/hardware-in-the-loop system specifically set up at the University of Pisa, in which the actuator voltage supply is regulated by a programmable power unit, and its mechanical loading is controlled by a counteracting hydraulic servo. The test results, obtained with different combinations of voltage supply and load factors, have been compared with the simulation results provided by a EMA model presented and discussed in the paper, pointing out its potentialities and limitations