Download or read book Force Fight Study in a Dual Electromechanical Actuator Configuration written by Daniel G. Wroble and published by . This book was released on 2017 with total page 121 pages. Available in PDF, EPUB and Kindle. Book excerpt: Electromechanical actuators (EMAs) are seen as the future actuation technology for next-generation, energy-optimized aircraft. Implementation into primary flight control entails many challenges and requires much research, development, and experience to prove the technology's robustness and maturity. Operation of multiple actuators on a control surface introduces a phenomenon known as force fight, where instead of equally sharing load they behave unequally or oppose each other. Force fight is well studied for hydraulic actuation systems, but limited research has been done on EMAs. The purpose of this thesis is to study force fight experimentally between two X-38 EMAs in a passive spring loaded dual EMA test rig. Static and dynamic analytical models of the test setup were created to assist the force fight study. The command to both EMAs was a 1-Hz, 5-degree-amplitude sine wave of ten cycles. Known force fight conditions of position lag, gain, and offset errors were introduced to each EMA in turn and the impacts of each condition were examined in terms of force difference and energy consumption. Torque, rotation, voltage, current, and power were measured from the test stand along with EMA controller position and current monitors for data analysis. Energy demand of the EMAs was calculated from the integral of the mechanical and electrical power. The force difference impact also was analyzed utilizing the maximum and minimum force difference as recorded on the torque cells. It was shown that all three cases, lag, gain, and offset, resulted in significant force fight between the two EMAs expressed as force difference. The magnitude of force fight was a linear function of the magnitude of the errors. In addition, both the gain and offset errors caused significant increase in total electrical energy demand, the larger the gain or offset, the higher the electrical energy demand, while the lag errors showed slight electrical energy increase. It also was shown that mechanical energy difference between the two EMAs did not increase noticeably with the increase of the errors for the gain and offset cases, while the lag test showed a significant amount of mechanical energy difference between the two EMAs. Lastly, the model prediction of the maximum and minimum force fight was shown in good agreement with the experimental test results and, therefore, it is believed that the models could serve as a tool to analyze force fight scenarios that are outside the capability of the test rig.