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Viewing 181 to 210 of 21014
2014-09-22
WIP Standard
J2174
This SAE Standard establishes the minimum performance requirements for electrical distribution systems for use in dollies and trailers in single or multiple configurations.
2014-09-20
Book
This is the electronic format of the Journal.
2014-09-18
Article
In this week's SAE Eye on Engineering, Senior Editor Lindsay Brooke questions if the so-called "driverless" cars of the future will also drive our car insurance rates down. SAE Eye on Engineering can be viewed at http://youtu.be/ecIWPopESAA.
2014-09-17
WIP Standard
AS90347A
No scope available.
2014-09-17
WIP Standard
AS21378A
No scope available.
2014-09-17
WIP Standard
AS90328A
No scope available.
2014-09-16
Article
Intrepid Control Systems’ new book Automotive Ethernet - The Definitive Guide describes the technology behind the biggest revolution in automotive networking since the 1980s.
2014-09-16
Technical Paper
2014-01-2202
Gene Tu, Wei Shih, Walter Yuen
Abstract To meet pulse power mode component cooling application needs, we developed, fabricated and tested a concept to use energy storage material and phase change material to enhance the heat dissipation of a conventional heat sink. Test results demonstrated the ESM/PCM heat sink has unique thermal performance. Under the same working condition, the peak temperature of ESM/PCM heat sink is 1.5°C lower than of a conventional heat sink. An optimized design can lead to a significant weight reduction for the heat sink in applications with high peak load and low duty power cycle power.
2014-09-16
Technical Paper
2014-01-2200
Hitoshi Oyori, Shingo Nakagawa, Hidefumi Saito, Norio Takahashi, Manabu Seta, Noriko Morioka
Abstract With the growth in onboard electrification referred to the movement of the More Electric Aircraft, or MEA, and constant improvement in ECO standards, aircraft electricity load has continued to soar. The airline and authors have discussed the nature of future aircraft systems in the next two decades, which envisages the further More Electric Aircraft or the All-Electric Aircraft, or AEA, concept helping provide some effective aviation improvements. The operators, pilots and maintenance crews anticipate improved operability, ease of maintenance and fuel saving, while meetings depends for high reliability and safety by electrification. As part of initial progress, the authors approach the methodology of energy management for aircraft systems. This study proposes some system options from three elements involving improvements to total energy management of several onboard systems, namely the environment control system, flight-control system, engine control system, landing gear system and electric power system.
2014-09-16
Technical Paper
2014-01-2190
Michael Ellis, William Anderson, Jared Montgomery
Under a program funded by the Air Force Research Laboratory (AFRL), Advanced Cooling Technologies, Inc. (ACT) has developed a series of passive thermal management techniques for cooling avionics. Many avionics packages are often exposed to environment temperatures much higher than the maximum allowable temperatures of the electronics. This condition prevents the rejection of waste heat generated by these electronics to the surrounding environment and results in significant ambient heat gain. As a result, heat must be transported to a remote sink. However, sink selection aboard modern aircraft is limited at best. Often, the only viable sink is aircraft fuel and, depending on mission profile, the fuel temperature can become too high to effectively cool avionics. As a result, the electronic components must operate at higher than intended temperatures during portions of the mission profile, which reduces component lifetime and significantly increases the probability of failure. To address this issue, ACT developed two passive thermal management approaches for avionics packages: heat pipe assemblies to reduce the internal temperature gradient and a Loop Heat Pipe (LHP) to transport thermal energy to alternative sinks.
2014-09-16
Technical Paper
2014-01-2196
Massimo Conte, Michele Trancossi
Abstract This paper introduces a new equipment, which allows autonomous landing and docking of a VTOL aircraft and any mobile system. It has been studied and developed inside the MAAT (Multibody Advanced Airship for Transport) EU FP7 project to control autonomous docking of manned cruiser and feeder airships in movement. After a detailed analysis it has been verified that It could be considered a technological spin off the MAAT project. It defines a new instrumental system for governing relative positioning between a movable target and VTOL air vehicles, such as helicopters, airships and multi-copters. This solution is expected to become a short time to market equipment for helicopters (both manned and unmanned) ensuring autonomous landing ability even in case of low visibility. Infrared emitters allow controlling both position and yaws angle. It is in advanced testing phase after a preliminary successful testing using a quadcopter. Tests has produced autonomous landing on a small platform mounted on an unmanned vehicle.
2014-09-16
Technical Paper
2014-01-2197
Didier Regis, Julie Berthon, Marc Gatti
Abstract For more than 40 years, Gordon Moore's experimental law has been predicting the evolution of the number of transistors in integrated circuits, thereby guiding electronics developments. Until last years, this evolution did not have any measurable impact on components' quality; but the trend is beginning to reverse. This paper is addressing the impact of scaling on the reliability of integrated circuits. It is analyzing - from both qualitative and quantitative point of view - the behavior of Deep Sub-Micron technologies in terms of robustness and reliability. It is particularly focusing on three basics of safety analyses for aeronautical systems: failure rates, lifetimes and atmospheric radiations' susceptibility.
2014-09-16
Technical Paper
2014-01-2195
James H. Graham, Roger Dixon, Peter Hubbard, Ian Harrington
On future UAVs it is envisaged that the power requirements of all on-board electrical systems will increase. In most flight (mission) situations the installed power generation will have adequate capacity to operate the aircraft. It is possible that during abnormal situations such as coolant blockage the generators on-board may be forced to operate under very high load conditions. The main failure mechanism for a generator is overheating and subsequent disintegration of windings, hence the research problem being addressed here is to manage the loads upon the generator to prevent overheats. The research presented here summarizes the modeling of the generator and formation of the load management system. Results are presented showing the system reallocating loads after a fault during flight, preventing overheat of the generators and successfully completing the mission.
2014-09-16
Technical Paper
2014-01-2213
Noriko Morioka, Hidefumi Saito, Norio Takahashi, Manabu Seta, Hitoshi Oyori
Abstract Electrical power management is a key technology in the AEA (All-Electric Aircraft) system, which manages the supply and demand of the electrical power in the entire aircraft system. However, the AEA system requires more than electrical power management alone. Adequate thermal management is also required, because the heat generated by aircraft systems and components increases with progressive system electrification, despite limited heat-sink capability in the aircraft. Since heat dissipation from power electronics such as electric motors, motor controllers and rectifiers, which are widely introduced into the AEA, becomes a key issue, an efficient cooling system architecture should be considered along with the AEA system concept. The more-electric architecture for the aircraft has been developed; mainly targeting reduced fuel burn and CO2 emissions from the aircraft, as well as leveraging ease of maintenance with electric/electronic components. The AEA should pursue more efficient and eco-friendlier systems, which are easier to maintain than those of conventional aircraft/MEA (More-Electric Aircraft), to enhance benefits for passengers and operators.
2014-09-16
Technical Paper
2014-01-2209
Marco Amrhein, Brian Raczkowski, Jason Wells, Eric Walters, Sean Field, Jason Gousy
Abstract Analyzing and maintaining power quality in an electrical power system (EPS) is essential to ensure that power generation, distribution, and loads function as expected within their designated operating regimes. Standards such as MIL-STD-704 and associated documents provide the framework for power quality metrics that need to be satisfied under varying operating conditions. However, analyzing these power quality metrics within a fully integrated EPS based solely on measurements of relevant signals is a different challenge that requires a separate framework containing rules for data acquisition, metric calculations, and applicability of metrics in certain operating conditions/modes. Many EPS employed throughout industry and government feature various alternating-current (ac) power systems. Ac systems have similar power quality metrics as direct-current (dc) systems, but also feature additional metrics for frequency and phase angle, which are part of the ac signal (unlike dc signals, for which frequency and phase angle have no meaning).
2014-09-16
Technical Paper
2014-01-2208
Michael Baldwin
Abstract This paper will illustrate how the increasing electrical power demands of military and aerospace applications can continue to successfully be met by high performance electromechanical relays. To meet these higher demands engineering compatibility must be properly understood between the intended application demands and relay switching performance parameters. With high performance electromechanical relays continuing to play a critical part in military and aerospace applications it is more important than ever that engineers capture all of the electrical power switching requirements. A critical area within powering military and aerospace systems is relay life when capacitive load switching. Capacitive loads generate high current levels that are transient in duration and often adversely affect the relay lifespan at the component level and the military or aerospace application reliability at the systems level. Often these transients, while brief in nature, can dramatically exceed the steady-state switching ratings for the contacts in a high performance electromechanical relay.
2014-09-16
Technical Paper
2014-01-2216
Mike Boost
Abstract Rechargeable lithium batteries are essentially ubiquitous in our daily lives and in virtually every industry from pocket key fobs to billion dollar space programs, in benign as well as extreme environments. Cell production in 2012 was estimated at 4.4 billion cells and expected to double by 2016. However within civil aviation, lithium batteries are still in the early stages of deployment. The general consensus within the industry is that the use of lithium batteries within civil aviation will increase substantially in the coming years. This paper focuses on design considerations with respect to deployment of rechargeable, or secondary, lithium batteries within civil aviation.
2014-09-16
Technical Paper
2014-01-2162
Viacheslav Pshikhopov, Mikhail Medvedev, Victor Krukhmalev, Roman Fedorenko, Boris Gurenko
Abstract The paper describes methods for control of docking of two moving stratospheric airships. One of them (cruiser) implements cruising flight at the defined altitude with defined velocity. The other one (feeder) fulfills the mission of chasing the cruiser with following docking operations. Mathematical model of exact airships are used in the work. Instances of structural and algorithmic implementation are based on position-trajectory controller. Simulation of docking control was accomplished with proposed methods.
2014-09-16
Technical Paper
2014-01-2164
Srikanth Gururajan, Mario Luca Fravolini, Matthew Rhudy, Antonio Moschitta, Marcello Napolitano
Abstract Recent catastrophic air crashes have shown that physical redundancy is not a foolproof option for failures on Air Data Systems (ADS) on an aircraft providing airspeed measurements. Since all the redundant sensors are subjected to the same environmental conditions in flight, a failure on one sensor could occur on the other sensors under certain conditions such as extreme weather; this class of failure is known in the literature as “common mode” failure. In this paper, different approaches to the problem of detection, identification and accommodation of failures on the Air Data System (ADS) of an aircraft are evaluated. This task can be divided into component tasks of equal criticality as Sensor Failure Detection and Identification (SFDI) and Sensor Failure Accommodation (SFA). Data from flight test experiments conducted using the WVU YF-22 unmanned research aircraft are used. Analytical redundancy is provided through a least squares modeling based approach and an extended Kalman filter approach to handle the Sensor Failure Accommodation (SFA) task.
2014-09-16
Technical Paper
2014-01-2166
Yamina Boughari, Ruxandra Botez, Georges Ghazi, Florian Theel
Abstract The main goal of this flight control system is to achieve good performance with acceptable flying quality within the specified flight envelope while ensuring robustness for model variations, such as mass variation due to fuel burn. The Cessna Citation X aircraft linear model is presented for different flight conditions to cover the aircraft's flight envelope, on which a robust controller is designed using the H-infinity method optimized by two heuristic algorithms. The optimal controller was used to achieve satisfactory dynamic characteristics for the longitudinal and lateral stability control augmentation systems with respect to this aircraft's flying quality requirements. The weighting functions of the H-infinity method were optimised by using both genetic and differential evolution algorithms. The evolutionary algorithms gave very good results. This is the first time these algorithms have been used in this form to optimize H-infinity controllers on a business aircraft, respecting both flying quality requirements and robustness criteria as objective functions and avoiding the use of other computationally complicated algorithms.
2014-09-16
Technical Paper
2014-01-2156
Arthur V. Radun
Abstract There is a continuing need to simulate power electronic circuits that include magnetic components. It is necessary to determine the interaction of the magnetic component with the rest of the power electronic system so that a dynamic circuit model of the magnetic components including material saturation and iron losses is required. Also, the magnetic component model must be valid when the magnetic component's excitation is not sinusoidal. A dynamic magnetic circuit model derived from Maxwell's equations along with useful theorems for building circuit models from the structure of the magnetic device is reviewed. The developed circuit models are general including magnetic saturation and iron losses. Simulation results for a DC/DC converter employing a conventional gapped inductor and a gapped coupled inductor are presented.
2014-09-16
Technical Paper
2014-01-2157
Puvan Arumugam, Chris Gerada, Serhiy Bozhko, He Zhang, Weeramundage Fernando, Antonino La Rocca, Stephen Pickering
Abstract This paper describes a high-speed electrical machine for an aircraft starter-generator. A surface mounted permanent magnet machine is designed to have minimal rotor losses and a novel cooling system for the stator. An inner stator sleeve is adopted to allow for a flooded stator whilst minimizing rotor windage losses. Different slot-pole combinations are compared in view of attaining an optimal combination that provides minimum losses whilst satisfying the electromagnetic, mechanical and thermal constraints.
2014-09-16
Technical Paper
2014-01-2158
James Borg Bartolo, Chris Gerada
Abstract A 45kW, switched reluctance type, starter-generator, having a 1:4 constant power speed range has been designed as a possible candidate for a regional jet application. In the first section of this paper, a review of the major starter-generator topologies considered for the aerospace application is provided, highlighting the advantages of choosing the Switched reluctance topology for such a safety critical application. Following this, the required torque speed characteristic of the machine, along with the imposed physical constraints, in terms of cooling and outer dimensions, are also detailed. Section III provides a description of the Electromagnetic design, and challenges encountered in meeting both the low speed, peak torque node, at 8000rpm, and the high speed, high power node, at 32000rpm. The induced mechanical stresses in the rotor at such high speeds have also been evaluated and used as a material selection criterion for such a design as presented in section III. Section IV, describes the thermal model developed to estimate the radial temperature distribution within the machine, taking into account end winding phenomena and cooling fluid constraints.
2014-09-16
Technical Paper
2014-01-2159
Richard Mourn
Abstract The paper provides an introduction into IEEE-1394, AS5643 and related documents. It then explores the I/O Technology Suitability Study criteria used to originally select IEEE-1394b (Beta) as the Vehicle System Data Bus for the F-35 Joint Strike Fighter and update each criterion with new information based on more than a decade of experience and use in not only the F-35 but several other programs. Based on the suitability study criteria, the reader gains insight into how and why programs like the F-35, which implements dozens of AS5643/IEEE-1394 devices per plane, utilize AS5643/IEEE-1394 for its vehicle system network. This unprecedented use of a high speed (491.52Mb/s) serial interface on an aircraft proves the capability of AS5643/1394, and opens the door for higher bandwidth communication between the Control Computer and remote nodes. While I/O bandwidth is important, system level deterministic behavior is required for most vehicle system networks and AS5643 coupled with 1394 provides the required deterministic behavior.
2014-09-16
Technical Paper
2014-01-2182
Evan Racine, Zachary Lammers, Street Barnett, John Murphy, Quinn Leland
Abstract The purpose of this study is to set up a laboratory test apparatus to analyze aircraft flight control EMAS' electrical and thermal energy flow under transient and dynamic flight profiles. A hydraulic load frame was used to exert load to the EMA. The actuator was placed within an environmental chamber which simulates ambient temperature as function of altitude. The simulated movement or stroke was carried out by the EMA. The under test EMA's dynamic load, stroke, and ambient temperature were synchronized through a real time Labview DAQ system. Motor drive voltage, current, regenerative current, and motor drive and motor winding temperature were recorded for energy analysis. The EMA under test was subjected to both transient and holding load laid out in a test matrix. It was found that the transient missions of EMAS presented the most electric demand on the aircraft electric power supply system while holding presented the most severe thermal stress on the EMAS, where the EMAS operated at 0% efficiency and all the electric power converted to heat.
2014-09-16
Technical Paper
2014-01-2181
Christopher Ian Hill, Chris Gerada, Paolo Giangrande, Serhiy Bozhko
Abstract This paper presents the initial development of a Modelica Library for Electro-Mechanical Actuator system analysis. At present two main system components are described, these are the Power Electronic Converter and Electric Machine, although further components will be added. These models provide the user with the ability to simulate Electric Machine and Power Electronic Converter systems including physical effects, losses and fault conditions. Established modelling programs such as Saber and MATLAB SimPowerSytems are often unable to provide all the aspects required to accurately simulate real systems in an easy to use, flexible manner. Therefore this paper shows how Modelica has been used to create versatile models able to simulate many practical aspects such as Power Electronic Converter losses and Power Electronic Converter faults, Electric Machine losses and Electric Machine faults. Examples are included in order to demonstrate the use of these models within a variety of systems including an Electro-Mechanical Actuator.
2014-09-16
Technical Paper
2014-01-2187
Teresa Donateo, Maria Grazia De Giorgi, Antonio Ficarella, Elisabetta Argentieri, Elena Rizzo
Abstract The present study aims at the implementation of a Matlab/Simulink environment to assess the performance (thrust, specific fuel consumption, aircraft/engine mass, cost, etc.) and environmental impact (greenhouse and pollutant emissions) of conventional and more electric aircrafts. In particular, the benefits of adopting more electric solutions for either aircrafts at given missions specifications can be evaluated. The software, named PLA.N.E.S, includes a design workflow for the input of aircraft specification, kind of architecture (e.g. series or parallel) and for the definition of each component including energy converter (piston engine, turboprop, turbojet, fuel cell, etc.), energy storage system (batteries, super-capacitors), auxiliaries and secondary power systems. It is also possible to setup different energy management strategies for the optimal control of the energy flows among engine, secondary equipment and storage systems during the mission. The tool is designed to be integrated with a multi-objective optimization environment.
Viewing 181 to 210 of 21014

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