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Technical Paper
2014-09-16
Rudolf Neydorf, Sergey Novikov, Nikita Kudinov
The airships constructors are exploring applications of the systems of many ballonets for roll airship control and attack angle airship control. However, this requires an effective automatic control system each of separately ballonet and for the entire system coordinated automatic control. This is especially necessary for unmanned airships and it makes it relevant the mathematical description, design and research of the systems and control laws for the airships having system of many ballonets. The automatic regulation of the system of many ballonets is a very difficult problem. This is because the some state variables of the separate ballonets are the technically not measurable variables. Mathematical model describes the change of the overpressure in the hull of the airship, and evaluates the process of this change. However, it does not allow calculating the mass of air in each ballonet. It is needs a system of differential equations for each of the ballonets. This is possible either by direct measurement of the volume of ballonets or by their dynamic identification as status variables.
Technical Paper
2014-09-16
Rudolf Neydorf, Youriy Sigida, Nikita Kudinov, Elena Portnova
During the development and study of airships controlled movements are applied computer simulation methods, since the size of these air vessels do not allow to apply physical modeling. Computer model is needed to simulate not only the shape and movement of the airship, but also the conditions (parameters) of the flight environment. It is atmospheric conditions typical for the air vessel route [R. Neydorf, V. Krukhmalev, N. Kudinov, V. Pshikhopov «Methods of Statistical Processing of Meteorological Data for the Tasks of Trajectory Planning of MAAT Feeders», SAE Technical Paper 2013-01-2266, 2013]. Atmospheric environment settings depend on the geographical position, the planned heights of flight of the aircraft, calendar and time periods (time of year, month, and time of day). In addition, the atmospheric parameters depend on the spontaneously emerging phenomena of weather conditions. As a result these variables have both a regular component and a random component. The first determined by both geographical conditions, and calendrical and time conditions.
Technical Paper
2014-09-16
Richard Mourn
The AS-1 Aircraft Systems and Systems Integration Committee is updating AS5643 and related standards and recommendations to accommodate both new develops and lessons learned from programs such as the F-35 Joint Strike Fighter and X-47B UCAS. This paper provides insight into how programs like the F-35, which implements more than 60 AS5643/IEEE-1394 devices per plane, utilize AS5643/IEEE-1394 for a 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 LRUs. 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. The paper then explains how 1394’s asynchronous stream capability is used by AS5643 to create a programmable rate-based (time-sliced) protocol that meets the rigorous requirements of advanced aerospace and defense system design all while using COTS silicon.
Technical Paper
2014-09-16
Didier Regis, Julie Berthon, Marc Gatti
In the last three decades, the integrated circuit industry has followed a steady path of constantly shrinking devices geometries and increased functionality that larger chips provide. These performances and functionality improvements have resulted in a history of new technology generations every two to three years, commonly referred to as .Moore Law. Each new generation has approximately doubled logic circuit density and increased performance by about 40%. Unfortunately these improvements may be reached today at the cost of a loss of reliability and operational lifetime. The increasing integration of embedded systems and the need to support new features requires high-performance and power-efficient processors. This trend pushes toward the use and development of components implemented in advanced CMOS technologies (22nm technology and bellow, the critical feature size of the elementary devices will drop to 5 nm in 2018, for 14 nm technology node). But, critical embedded computing systems have also to fulfill specific safety requirements.
Technical Paper
2014-09-16
Shweta Sanjeev, Goutham Selvaraj, Patrick Franks, Kaushik Rajashekara
In a More Electric Aircraft, there is a need to integrate power electronics with the starter generator system. The power electronics operates in the hostile engine environment. This requires use of power devices and passive components that are capable of operating at high temperatures (200-250 C). Wide band gap materials such as Silicon-Carbide (SiC) and Gallium Nitride (GaN) are used as power devices to provide the power conversion at high temperature. In this project, a 50 kVA high temperature bi-directional converter provides the power conversion for starter generator system at 200 C, which can be directly mounted on the engine compartment. The converter is a three phase PWM active rectifier, based on SiC MOSFET. During starter mode, the converter acts as an inverter providing AC voltage to the motor to start the engine During generator mode it functions as an active rectifier converting the AC voltage to 540V DC (+/-270V DC). The DC output of the converter provides power to the platform’s HVDC loads, DC-AC inverter fed AC loads and 28V DC loads.
Technical Paper
2014-09-16
David Gras, Christophe Pautrel, Amir Fanaei, Gregory Thepaut, Maxime Chabert, Fabien Laplace, Gonzalo Picun
Power systems are continuously looking for high efficiency systems especially for high temperature applications where self-heating margin is very small. In applications such as Intelligent Power Modules (IPM), Motor Drives, and Power Inverters, high efficiency, high voltage and high temperature Silicon Carbide (SiC) and Gallium Nitride (GaN) power transistors are being used in several industries including aeronautics & aerospace, automotive, and down-hole. In this paper, we present a highly integrated, high-temperature solution for driving such power transistor. The solution is composed of the XTR26010 (High-Temperature Intelligent Gate Driver) with the XTR40010 (High-Temperature Isolated Two Channel Transceiver) for isolated gate drive, and XTR30010 (High-Temperature PWM Controller) with XTR2N0825 (High-Temperature 80V N-Channel Power MOSFET) for isolated power supply. XTR26010 is a high-temperature, high reliability isolated power transistor driver integrated circuit, designed with a high focus on offering a robust, reliable, compact and efficient solution for driving a large variety of high-temperature, high-voltage, and high efficiency power transistors.
Technical Paper
2014-09-16
Gregory J. Moore, Frank Puglia, Lawrence Myron, Stephen Lasher, Bob Doane, Joe Gnanaraj, Seth Cohen, Arthur Dobley, Ryan Lawrence, Rong Yan
For 70 years Yardney has been a leader in specialty battery and energy systems for military, space, avionics, weapon systems and undersea vehicles. Yardney has evolved since beginning in 1944 in New York City, to Pawcatuck, CT, and since 2013 resides in East Greenwich, RI. The chemistries provided in this time include silver-zinc, magnesium silver chloride, lithium thionyl-chloride, nickel zinc, lithium-ion (Li-ion) and several metal-air technologies. Yardney has made cells from 50 mAh for human implantables to 1000 Ah for submersible vehicles. In addition to battery systems, Yardney also pursues hybrid systems for ground, space, undersea and avionic applications. The beauty of hybrid systems, combining energy sources such as batteries, capacitors, fuel cells and solar, is that they can be used to optimize energy and power density, and with proper design lead to longevity of components and an overall cost savings. Where fuel cells can provide the most energy of these specified constituents on a large scale, at a smaller scale they come at a cost due to their inefficiencies and their bulk.
Technical Paper
2014-09-16
Kazuki Shibata, Tomo Maedomari, Kenichi Rinoie, Noriko Morioka, Hitoshi Oyori
In aircraft conceptual design, we consider several different configurations and systems so that performance requirement can be satisfied. When choosing many sets of parameters, designers try to make all the objective functions as good as possible, and then determine the best aircraft configuration. In this case, however, the feasibility of this best aircraft configuration is somewhat doubtful because we haven’t considered aircraft secondary power systems which are indispensable for aircraft operation. Therefore we need to include the consideration of aircraft secondary power systems into the conceptual design. Past studies of conceptual designs with aircraft secondary power systems are few compared with those into which detailed analyses of aerodynamics, structural dynamics, flight stability and propulsion have been integrated. One reason might be that detailed data of existing aircraft is difficult to obtain. Second, basic methods which integrate secondary power systems analyses into conceptual design process haven’t been discussed in detail in the literature.
Technical Paper
2014-09-16
Manxue Lu
This article attempts to provide a big picture of systems engineering in both philosophy and engineering perspectives, discusses current status and issues, trends of systems engineering development, future directions and challenges, followed by certain examples.
Technical Paper
2014-09-16
Hitoshi Oyori, Shingo Nakagawa, Hidefumi Saito, Norio Takahashi, Manabu Seta, Noriko Morioka
With the growth of onboard electrification and the constant improvement of ECO standards, aircraft electricity load has maintained a rapid, high growth. The More Electric Architecture for Aircraft and Propulsion (MEAAP) is emerging as a viable solution for improved performance and eco-friendly aircraft operations. This study proposes a conceptual system design of All Electric Aircraft, or AEA, incorporated with electrical management for onboard systems. The authors have discussed the future of aviation with an airliner. The airliner imagines the likelihood of some effective improvements in aviation by More Electric Aircraft concept. The operators, the pilots and the maintenance crews expect improvement of operability, maintainability and fuel saving, while requiring high reliability and safety. System designers struggle to optimize lighter weight, shorter propulsion operating and lower cost as well as these requests. This study proposes three points for optimization of onboard systems, which are environment control system, flight control system, engine control system, landing gear system and electric power system.
Technical Paper
2014-09-16
Dave Duncan
DO-254 Verification and Validation (Derived requirements and Robustness testing
Technical Paper
2014-09-16
Noriko Morioka, Hidefumi Saito, Norio Takahashi, Manabu Seta, Hitoshi Oyori
Aircraft system architecture has been continuously changing to improve aircraft efficiency, operability, reliability and safety. Airlines always expect the improvement by any possible approaches, because it is very important for not only safe operation of the aircrafts, environmental consideration such as reduction of CO2 and noise emissions, but also economical reason such as efficient aircraft operation and fuel cost saving. It takes huge effort to change the aircraft system architecture, but along with technology advancement of power electronics, electrification of the system has been gradually introduced into the commercial aircrafts. Conventional aircraft systems have long used a four power drive source: mechanical power, hydraulic power, pneumatic power and electric power. Then concept of More Electric Aircraft (MEA) emerged, replacing mechanical, hydraulic and pneumatic aircraft system power sources with electrical power. With the controllability of electric systems, an MEA system will efficiently and adequately manage energy and power throughout the entire aircraft mission.
Technical Paper
2014-09-16
Evan Racine, Zachary Lammers, Street Barnett, John Murphy, Quinn Leland
Electromechanical Actuation System (EMAS) faces some major technological challenges before it could be fully adopted for primary flight control of aircraft, replacing conventional hydraulic actuation system. One of the challenges is the thermal management of EMAS. The working fluid in conventional hydraulic actuation system acts as a coolant while EMAS does not have a readily available heat sink. Another technical challenge facing EMAS for primary flight control is its highly dynamic demand on aircraft electric power system. Its high peak power demand and regenerative power pose a challenge to aircraft electric power generation and distribution system. The purpose of this study is to analyze EMAS’ transient and dynamic electrical and thermal energy flow under a simulated flight envelope and thermal environment. A laboratory test apparatus was set up to evaluate and characterize the energy flow of an EMA subjected to a simulated dynamic flight control surface load and thermal environment.
Technical Paper
2014-09-16
Christopher Ian Hill, Chris Gerada, Paolo Giangrande, Serhiy Bozhko
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.
Technical Paper
2014-09-16
Jay Wilhelm, Joseph Close, Wade Huebsch
A Hybrid Projectile (HP) is an aerial vehicle that is ballistically launched, and then transforms into an Unmanned Aerial Vehicle (UAV). It was desirable for a surveillance equipped HP to change its trajectory, and ultimately the point of impact, by departing from its ballistic trajectory after being launched. The exact control surface sizes, location, and actuation along with the control strategies were needed. A method was investigated to utilize deflectable control surfaces in conjunction with a guidance system to maneuver to HP to a desired point of impact while ensuring that the projectile remains statically and dynamically stable. Dual feedback control methods were devised to control heading and pitch using deflectable vertical and horizontal tail surfaces. These control methods were tested and tuned using the Six Degree of Freedom (6DoF) system in Simulink. A cruciform tail section, analyzed in previous work for a 40 mm HP, was utilized so that the HP was statically and dynamically stable.
Technical Paper
2014-09-16
Prashant Vadgaonkar
Today's digital avionics systems leverages the maximum use of the Embedded COTS to fit the need of small form factor, low power, reduce time to market, reducing development time and efficient use of DO-254 for compliance of product. Without the use of Embedded COTS Hardware the time to market is more, compliance efforts are high and complexity of the design increases dramatically. COTs are very useful for Development Assurance Level C and below, new trend is to use it for Level A and B as well, where we can get enormous benefit on efforts on compliance and time to market. COTS modules are entering in digital avionics systems as COM (Computer On Module)/SOM (System On Module)/SIP (System In Package) with huge advancement in semiconductor and packaging industry. Digital systems like cockpit (Drive for Digital Cockpit), Air data management and Fuel Quantity Gauging and Indicating Systems etc. leveraging the COTS for their redesigns, to invent/evolve new products in digital avionics segment.
Book
2014-09-04
William C. Messner
Over the years, the DARPA Challenges in the United States have galvanized interest in autonomous cars, making them a real possibility in the mind of the public, but autonomous and unmanned vehicles have been increasingly employed in many roles on land, in the water, and in the air. Military applications have received a great deal of attention, with weaponized unmanned aircraft (drones) being the most prominent. However, unmanned vehicles with varying degrees of autonomy already have many civilian applications. Some of these are quite familiar (such as the Roomba autonomous vacuum cleaner), while others remain largely out of the public eye (such as autonomous farm equipment). Additional applications and more capable vehicles are rapidly coming to the markets in the years ahead. This book examines a number of economically important areas in which unmanned and autonomous vehicles, also understood here as autonomous technologies, are already used or soon will be. Co-published by SAE International and AUVSI, Autonomous Technologies: Applications That Matter will assist the reader in identifying profitable opportunities and avoiding costly misconceptions with respect to civilian applications of autonomous vehicle technologies as it brings together chapters on how air, water, and ground vehicles are becoming ever more used and appreciated.
Technical Paper
2014-09-01
Zachary A. Collier, Steve Walters, Dan DiMase, Jeffrey M. Keisler, Igor Linkov
Counterfeit electronic components entering into critical infrastructure and applications through the global supply chain threaten the economy and national security. In response to the growing threat from counterfeits, the Society of Automotive Engineers G-19 Committee is developing AS6171. This aerospace standard is focused on testing facilities with a goal of standardizing the process of counterfeit detection. An integral part of the standard is a semi-quantitative risk assessment method. This method assigns risk scores to electronic components based on a number of relevant criteria, and places the components into one of five risk tier levels corresponding to an appropriate level of laboratory testing to ensure the authenticity of the component. In this way, the methodology aims at standardizing the risk assessment process and bases the identified risk as guidance for commensurate testing protocols. This paper outlines the risk assessment method contained within AS6171 and briefly explores other complementary efforts and research gaps within the G-19 and electronics community.
Article
2014-07-30
The Electric Power Research Institute has announced a collaboration with 8 automakers and 15 utilities to develop and demonstrate an open grid integration platform for plug-in electric vehicles (PEVs).
Article
2014-07-29
Jaguar Land Rover (JLR)'s all-new Ingenium modular, turbocharged gasoline and diesel engine range targets significant internal friction reduction by using rolling-element bearings to support camshafts and balance shafts.
Standard
2014-07-29
This document defines a set of standard application layer interfaces called JAUS Unmanned Ground Vehicle Services. JAUS Services provide the means for software entities in an unmanned system or system of unmanned systems to communicate and coordinate their activities. The Unmanned Ground Vehicle Services represent the platform-specific capabilities commonly found in UGVs, and augment the Mobilty Service Set [AS6009] which is platform-agnostic. At present ten (10) services are defined in this document.
Standard
2014-07-29
This SAE Aerospace Information Report (AIR) describes the design approaches used for current applications of aircraft Brake-by-Wire (BBW) control systems. The document also discusses the experience gained during service, and covers system, ergonomic, hardware, and development aspects. The document includes the lessons that have been learned during application of the technology. Although there are a variety of approaches that have been used in the design of BBW systems, the main focus of this document is on the current state of the art systems.
Article
2014-07-27
FLEXConnect audio-video bridging system from Mitsubishi Electric Automotive America, Inc. is a next-generation in-vehicle infotainment system that provides flexibility for multiple displays and multiple content streams, allowing passengers to enjoy individual entertainment preferences.
Article
2014-07-24
Joysticks are evolving rapidly, improving ergonomics to help improve operator efficiency and increase safety and reliability.
Article
2014-07-24
SAE International recently published J2601 “Fueling Protocols for Light Duty Gaseous Hydrogen Surface Vehicles,” the light-duty hydrogen-fueling protocol that will serve as the baseline for fueling the first generation of hydrogen fuel cell electric vehicle (FCEVs).
Standard
2014-07-24
This SAE Recommended Practice applies to the use of generally available leak detection methods to service motor vehicle passenger compartment air conditioning systems.
WIP Standard
2014-07-23
This specification covers the requirements for radio frequency absorptive component wires and finished cables which function electrically as distributed low-pass filters. Materials and construction details are specified in the applicable specification sheet.
WIP Standard
2014-07-22
SPECIFICATION COVERS A TAPE STYLE DEVICE FOR REPAIRING LARGER SIZE PRIMARY WIRE.
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