Advanced Electromechanical Actuation System (EMAS) Development and Flight Test (C-141 Aircraft) Demonstration
Author: T. Mark Bailey
Publisher:
Published: 1988
Total Pages: 336
ISBN-13:
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Advanced Electromechanical Actuation System (EMAS), Flight Test
Author:
Publisher:
Published: 1986
Total Pages: 138
ISBN-13:
DOWNLOAD EBOOKThe EMAS flight test project successfully demonstrated, for the first time, the electrical actuation of a primary flight control surface in flight. This test was a major step toward the realization of the All-Electric Airplane (AEA) concept. An electric actuator was installed in a modified C-141A aircraft to power the left aileron. Testing included ground and flight trials to ensure unchanged control system damping. Aircraft roll performance tests included maximum effort rolls, degraded system rolls, and autopilot rolls. Sideslip and trim test points were also performed. It was verified that EMAS performance was similar to the normal hydraulic actuator. Results include lessons on aircraft modification, general system characteristics, maintenance factors, and compatibility with other aircraft systems that may influence future installations. Keywords: Electromechanical actuation system; Ailerons; Flight controls; Damping.
Electro-Mechanical Actuators for the More Electric Aircraft
Author: Mirko Mazzoleni
Publisher: Springer Nature
Published: 2021-01-19
Total Pages: 256
ISBN-13: 3030617998
DOWNLOAD EBOOKThis book presents recent results on fault diagnosis and condition monitoring of airborne electromechanical actuators, illustrating both algorithmic and hardware design solutions to enhance the reliability of onboard more electric aircraft. The book begins with an introduction to the current trends in the development of electrically powered actuation systems for aerospace applications. Practical examples are proposed to help present approaches to reliability, availability, maintainability and safety analysis of airborne equipment. The terminology and main strategies for fault diagnosis and condition monitoring are then reviewed. The core of the book focuses on the presentation of relevant case studies of fault diagnosis and monitoring design for airborne electromechanical actuators, using different techniques. The last part of the book is devoted to a summary of lessons learned and practical suggestions for the design of fault diagnosis solutions of complex airborne systems. The book is written with the idea of providing practical guidelines on the development of fault diagnosis and monitoring algorithms for airborne electromechanical actuators. It will be of interest to practitioners in aerospace, mechanical, electronic, reliability and systems engineering, as well as researchers and postgraduates interested in dynamical systems, automatic control and safety-critical systems. Advances in Industrial Control reports and encourages the transfer of technology in control engineering. The rapid development of control technology has an impact on all areas of the control discipline. The series offers an opportunity for researchers to present an extended exposition of new work in all aspects of industrial control.
Thermal Management of Electromechanical Actuation System for Aircraft Primary Flight Control Surfaces
Author: Zachary A. Lammers
Publisher:
Published: 2014
Total Pages: 271
ISBN-13:
DOWNLOAD EBOOKElectromechanical Actuation Systems (EMAS) are a key component in the More Electric Aircraft (MEA). EMAS operate on a "power on demand" basis reducing energy consumption typically required by hydraulic systems to maintain hydraulic pressure. Additionally, EMAS reduce system weight; lessening system maintenance and operating costs. EMAS convert electrical energy to mechanical energy via an electric rotary machine combined with a rotary to linear or rotary to rotary conversion mechanism. Electrical energy required to complete useful mechanical output depends on the efficiency of the system. Therefore, it is important to characterize electrical and thermal loads associated with an EMAS for primary flight control surfaces, such as an aileron. Electric power draw and thermal management are among the most important parameters of research in electromehcanical actuation for a primary flight control (PFC) surface. The aim of this thesis was to build an experimental EMAS system and methodology to analyze EMAS performance against realistic duty cycles and mission environments. Thermal energy in addition to the rate of change of temperature and temperature difference for temperature sensitive components was used to determine the most thermally malignant profiles and potential thermal design points. It was found that transient missions of an EMAS presented the greatest electric demand of the aircraft electric power supply system, and holding presented the greatest thermal stress of the EMAS, where the EMAS operated at 0% efficiency and all electric power was converted to heat.
Force Fight Study in a Dual Electromechanical Actuator Configuration
Author: Daniel G. Wroble
Publisher:
Published: 2017
Total Pages: 121
ISBN-13:
DOWNLOAD EBOOKElectromechanical 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.
A System Look at Electromechanical Actuation for Primary Flight Control
Author: E. A. Lomonova
Publisher:
Published: 1997
Total Pages: 132
ISBN-13:
DOWNLOAD EBOOKElectro-Mechanical Actuators for Safety-Critical Aerospace Applications
Author: Gianpietro Di Rito
Publisher: Mdpi AG
Published: 2023-06-12
Total Pages: 0
ISBN-13: 9783036579337
DOWNLOAD EBOOKAircraft electrification is one of the most important and strategic initiatives currently supporting the innovation of the aviation industry. This manifests in the well-known more-electric aircraft concept (with the ultimate aim of achieving the all-electric long-term target), which aims to gradually replace onboard systems based on mechanical, hydraulic, or pneumatic power sources with electrically powered ones to reduce the weight and costs, optimize energy, and increase the eco-compatibility and reliability of future aircrafts. A key technological enabler for pursuing these challenging objectives is electro-mechanical actuation. The applicability of electro-mechanical actuators (EMAs) in aerospace has been proved in terms of dynamic performances, but it still entails several concerns in terms of reliability/safety and operation in a harsh environment. In civil aircrafts, EMAs are often avoided for safety-critical functions (flight controls, brakes, landing gears, and nose wheel steering), essentially because the statistical database on the components' fault modes is poor. This Special Issue is thus focused on advancements and innovations in the design, modelling/simulation, architectural definition, reliability/safety analysis, control, condition-monitoring, and experimental testing of EMAs developed for safety-critical aerospace applications. The research papers included in this Special Issue will undoubtedly contribute to progress towards the objective of more electric flights.
Laboratory Test Set-up to Evaluate Electromechanical Actuation System for Aircraft Flight Control
Author: Street A. Barnett
Publisher:
Published: 2015
Total Pages: 99
ISBN-13:
DOWNLOAD EBOOKA laboratory apparatus and data acquisition system were constructed for evaluating aircraft flight control actuators under simulated mission profiles. A MTS hydraulic load frame was used to simulate a control surface's aero load. A NI based DAQ system was used to record the motor controller's DC bus voltage at a high rate, actuator's position, load, and temperatures. The DC bus rms voltage, current, and power, and regenerative power were recorded by a Newton's 4th power analyzer. Key performance characteristics tests such as frequency response, step response, reversal, backlash, and holding with a Danahar EC5 actuator were carried out to verify this laboratory setup.The continuous frequency sweeping test revealed that the EMA reached the speed limit first, then the current limit, and finally the temperature limit. When the actuator's electronics reached the thermal limit, the actuator controller drastically reduced its power. This caused drastic magnitude attenuation and phase lagging. Continuous frequency sweeping proved to be a useful test to evaluate the EMA's characteristics. The lab tests showed that holding presents the most significant challenge to the thermal management of an EMA system. To reduce the thermal gradient within the motor, a half rotation back forth at 0.01 Hz sinusoidal disturbance was imposed during holding to evenly engage the motor's three phases. This resulted in an 81% temperature variation reduction among the three windings. Although this small motion disturbance is effective in reducing the motor and motor drive's thermal gradient, it is not known if such a disturbance is feasible in practice.The step response and reversal test showed that when an EMA reverses direction or suddenly decelerates, a significant spike of regenerative power occurred. This regenerative power could present itself as a thermal challenge to an aircraft flight control EMA system.Using the MTS hydraulic load frame to simulate a dynamic aero load of a flight control surface in synchronization with position movement of an actuator proved to be a challenge. A double loop control scheme has been derived which compensates the time delay difference between the load frame and the actuator. It is our hope that this control strategy, once fully implemented, will enable more accurate dynamic load control in simulating an EMA's mission profile for performance evaluation.
Scientific and Technical Aerospace Reports
Author:
Publisher:
Published: 1987
Total Pages: 956
ISBN-13:
DOWNLOAD EBOOKAdvanced Flight Control Actuation System (AFCAS - E/P). Fabrication and Design Verification Testing of a Dual Mode Electro/Pneumatic Actuator for the T-2C Aircraft
Author: Wallace Kineyko
Publisher:
Published: 1982
Total Pages: 55
ISBN-13:
DOWNLOAD EBOOKReport of the fabrication and design verification testing of a Dual Mode Electro/Pneumatic Actuator. Pneumatic model open loop operation and control verified. Torque/Speed performance less than design goal due to excessive gear separation force. (Author).
