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Technical Paper
2014-09-16
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.
Technical Paper
2014-09-16
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.
Technical Paper
2014-09-16
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.
Technical Paper
2014-09-16
Ralf Cremer, Alfred Engler
Abstract The application of power electronics in aircraft is increasing in the latest aircraft developments. This contribution focuses on the recent advances of activities at Liebherr-Elektronik GmbH linked to power electronics: active power filter based on fast silicon carbide switches, open box design for unpressurized area, light weight housing, EMC management, partial discharge detection and mitigation, arc-fault detection and standardized innovative power cores with optimized sensors. These topics are derived from a roadmap based on beforehand identified key drivers. These key drivers will enable the future More Electric Aircraft (MEA) by focusing on weight, reliability and cost. New technologies as Silicon Carbide (SiC) and advanced integration will support this strategy.
Technical Paper
2014-09-16
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.
Technical Paper
2014-09-16
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).
Technical Paper
2014-09-16
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.
Technical Paper
2014-09-16
Javier Gazzarri, Nishant Shrivastava, Robyn Jackey, Craig Borghesani
Abstract Battery Management System (BMS) design is a complex task requiring sophisticated models that mimic the electrochemical behavior of the battery cell under a variety of operating conditions. Equivalent circuits are well-suited for this task because they offer a balance between fidelity and simulation speed, their parameters reflect direct experimental observations, and they are scalable. Scalability is particularly important at the real time simulation stage, where a model of the battery pack runs on a real-time simulator that is physically connected to the peripheral hardware in charge of monitoring and control. With modern battery systems comprising hundreds of cells, it is important to employ a modeling and simulation approach that is capable of handling numerous simultaneous instances of the basic unit cell while maintaining real time performance. In previous publications we presented a technique for the creation of a battery cell model that contains the electrochemical fingerprints of a battery cell based on equivalent circuit model fitting to experimental data.
Technical Paper
2014-09-16
Fan Frank Wang
Abstract This article is about the issues associated with the published thermal data from commercial off the shelf (COTS) component manufacturers. Some of the published electrical component thermal data can be confusing and/or misleading. This article discusses the possibility of wrong design decisions that can be made using published COTS thermal data. There are two major issues of the published thermal data associated with the use of COTS components. One is the published ambient temperature rating. Another is the published thermal resistance. This paper will discuss these two major issues in details and provide mitigation suggestions.
Technical Paper
2014-09-16
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.
Technical Paper
2014-09-16
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.
Technical Paper
2014-09-16
Prashant Vadgaonkar
Abstract Today's digital avionics systems leverage the use of the Embedded COTS (Commercial Off The Shelf) hardware to fit the need of small form factor, low power, reduced time to market and reduced development time with efficient use of DO-254 for compliance of product. COTS modules are entering in digital avionics systems such as COM (Computer On Module)/SOM (System On Module)/SIP (System In Package) with huge advancement in semiconductor and packaging industry. In today's scenario COTS are very useful for DAL (Development Assurance Level) C and below as the efforts on compliance for DAL A and B are huge. This paper proposes to use these for DAL A and B as well, where one can get enormous benefit on efforts of compliance and time to market. This paper makes an attempt to explain the current scenario of the Embedded COTS usage in Avionics Systems. This paper also brings the study of the selection process of Embedded COTS along with the important selection parameters, constraints, challenges and guidelines.
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
Abstract For 70 years Yardney has been a leader in specialty battery and energy systems for military, space, avionics, weapon systems and undersea vehicles. In addition to battery systems, Yardney also delivers 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, the systems can also lead to longevity of components and an overall cost savings. For ground applications, utilization of hybrid systems can assist in conservation of fuel by making vehicle applications more efficient. For space applications, satisfying pulses can be improved by a capacitor and battery hybrid energy storage system. To optimize aircraft performance and decrease operating costs, avionics are beginning to move towards more electric aircrafts (MEA). This embraces the concept of utilizing electrical power for driving aircraft subsystems currently powered by mechanical means.
Technical Paper
2014-09-16
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.
Technical Paper
2014-09-16
Evgeni Ganev, William Warr, Keming Chen
Abstract This paper presents a novel method and system for an electric power alternating-current (AC)-to-direct-current (DC) converter employing composite technology. The term composite entails utilization of more than one type of conversion operating in parallel. In addition, background information for the prior art, based on conventional autotransformer rectifier units (ATRUs), and active converters are discussed. The major requirements of AC-to-DC converters from both functional and protection perspectives are provided. The concept of the new approach is defined. Comparative analysis between the new and old methods is documented. The performance features and technical details of the system parameters with respect to AC-to-DC converter system requirements are presented and discussed. Analysis, simulation results, and test data are included. Finally, the advantages of this technology, which nearly doubles power density compared to the state-of-the-art, are summarized and a conclusion included.
Technical Paper
2014-09-16
Thierry Cornilleau, Pierre Linard, Paul Moxon, Christopher Nicholas
Abstract ECOA is an active software architecture research programme conducted by the French Republic and United Kingdom. It is one product of the recent Defence and Security Co-operation Treaty signed between the two nations. This paper provides an overview of the programme goals and progress as well as an introduction to the technology being developed and comparison to related initiatives. The goal of the ECOA programme is to define an open software architecture that enables collaborative development of mission system software. The ECOA programme is needed to reduce development and lifecycle costs of future military air programmes. For this reason the programme has a specific focus on combat-air mission systems but the underlying technology is general purpose, applying to multiple military and civil domains. At present, the programme has defined a concept, delivered a set of initial technical standards and produced a joint demonstrator to validate the technology developed.
Article
2014-09-15
Germany's ZF has entered into a definitive agreement to acquire U.S.-based TRW Automotive Holdings Corp. for $13.5 billion, according to a Sept. 15 TRW press release. ZF has stated that TRW will be operated as a separate business division within ZF.
Article
2014-09-15
With the recent focus on the efficiency of vehicle electronics, automotive manufacturers are looking for tantalum capacitors with lower equivalent series resistance.
Article
2014-09-15
Excelfore enables simplified audio-video interconnectivity using Ethernet audio-video bridging, which leads to lower cost and system weight for infotainment systems in vehicles.
Article
2014-09-15
Sunex NoGhost 120dB lenses are the first and only lenses designed, optimized, and tested for use in cameras using high dynamic range image sensors, claims the company.
Article
2014-09-15
Q-Prime from Multek Flexible Circuits Inc. is a flexible circuit technology developed specifically for applications where efficient heat dispersion is required, and is especially useful for LED applications.
Article
2014-09-15
With its small size of 5.08 x 2.54 x 0.4 mm (0.20 x 0.10 x 0.02 in), high load capacity, and precision, Isabellenhütte’s gold-plated VMP-A resistor is suitable for automobile engine and transmission modules as well as power hybrids and power modules (DCB ceramic) in frequency converters. The VMP-A resistor is a member of the VMx precision resistor family with gold-plated contacts.
Article
2014-09-12
The new RR25 rotary speed sensor from Dynapar, which targets agricultural applications in the off-highway vehicle market, uses proven Hall-IC technology to provide reliable service in demanding environments where contaminants, corrosive chemicals, and high vibration are commonplace.
Article
2014-09-12
High-performance metamaterial antennas could be compact, lightweight, conformable, and stealthy.
Standard
2014-09-12
This document is an annex to EIA Engineering Bulletin SSB-1. Guidelines for Using Plastic Encapsulated Microcircuits and Semiconductors in Military, Aerospace and Other Rugged Applications. This document provides reference information concerning the environmental stresses associated with tests specifically designed to apply to (or have unique implications for) plastic encapsulated microcircuits and semiconductors, and the specific failures induced by these environmental stresses.
Standard
2014-09-12
This document is an annex to EIA Engineering Bulletin, SSB-1, Guidelines for Using Plastic Encapsulated Microcircuits and Semiconductors in Military, Aerospace and Other Rugges Applications (the latest revision). The scope of this document is to establish the recommended minimum qualification and monitoring testing of plastic encapsulated microcircuits and discrete semiconductors suitable for potential use in many rugged, military, severe, or other environments.
Standard
2014-09-12
This document is an annex to EIA Engineering Bulletin SAB-1, Guidelines for Using Plastic Encapsulated Microcircuits and Semiconductors in Military, Aerospace and Other Rugged Applications (the latest revision). This document provided reference information concerning acceleration factors commonly used by device manufacturers to model failure rates in conjunction with statistical reliability monitoring. These acceleration factors are frequently used by OEMs in conjunction with physics of failure reliability analysis to assess the suitability of plastic encapsulated microcircuits and semiconductors for specific end use applications.
Standard
2014-09-11
This specification covers Terminal Junction System (TJS) components which are used for interconnection of wiring and incorporation of passive components (see 6.1). These environment resistant components have in common the use of crimp type external pin contacts in accordance with AS39029/1 for Series I or crimp type external socket contacts in accordance with AS39029/22 for Series II. This family of TJS components is designed to operate continuously over a temperature range of -65 to 200 °C, using any combination of temperatures generated by the electrical load and ambient temperature so that the maximum internal hot spot, combined temperature, will not exceed the maximum specified for the class of TJS component, unless otherwise specified.
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