7,508 research outputs found
Fly-By-Wireless for Next Generation Aircraft: Challenges and Potential solutions
âFly-By-Wirelessâ paradigm based on wireless connectivity in aircraft has the potential to improve efficiency and flexibility, while reducing weight, fuel consumption and maintenance costs. In this paper, first, the opportunities and challenges for wireless technologies in safety-critical avionics context are discussed. Then, the assessment of such technologies versus avionics requirements is provided in order to select the most appropriate one for a wireless aircraft application. As a result, the design of a Wireless Avionics Network based on Ultra WideBand technology is investigated, considering the issues of determinism, reliability and security
Managing Triads in a Military Avionics Service Maintenance Network in Taiwan
Purpose â The purpose of this paper is to investigate how different types of
triad structures, and the management mechanisms adopted by the focal company,
affect cooperative performance. Design/methodology/approach â This paper uses a
social network perspective to examine the triad management phenomenon in the
military avionics maintenance context, which is closely associated with the
field of operations management. Findings â This paper demonstrates that
different triad structures and management mechanisms influence perceived
cooperative performance. Four main findings emerged: in a triad, a firm playing
a bridging role perceives higher cooperative performance than when playing a
peripheral role in the triad or being located in a fully connected triad. When a
firm plays the bridging role in a triad, and has a high level of trust, this
leads to higher perceived cooperative performance. When a firm plays a
peripheral role in a triad, high levels of coordination mechanism combined with
high levels of trust result in higher levels of perceived cooperative
performance. In a fully linked triad, when the coordination mechanism is well
developed, the level of trust is high, so that the resulting level of perceived
cooperation is high. Originality/value â This paper extends the knowledge of
triad management by providing an in-depth study of a well-defined network
setting with exceptionally high-level access to the most senior executives. In
practice, this paper shows how to manage differen
Cargo launch vehicles to low earth orbit
There are two primary space transportation capabilities required to support both base programs and expanded mission requirements: earth-to-orbit (ETO) transportation systems and space transfer vehicle systems. Existing and new ETO vehicles required to support mission requirements, and planned robotic missions, along with currently planned ETO vehicles are provided. Lunar outposts, Mars' outposts, base and expanded model, ETO vehicles, advanced avionics technologies, expert systems, network architecture and operations systems, and technology transfer are discussed
Advanced Manned Launch System (AMLS) study
To assure national leadership in space operations and exploration in the future, NASA must be able to provide cost effective and operationally efficient space transportation. Several NASA studies and the joint NASA/DoD Space Transportation Architecture Studies (STAS) have shown the need for a multi-vehicle space transportation system with designs driven by enhanced operations and low costs. NASA is currently studying an advanced manned launch system (AMLS) approach to transport crew and cargo to the Space Station Freedom. Several single and multiple stage systems from air-breathing to all-rocket concepts are being examined in a series of studies potential replacements for the Space Shuttle launch system in the 2000-2010 time frame. Rockwell International Corporation, under contract to the NASA Langley Research Center, has analyzed a two-stage all-rocket concept to determine whether this class of vehicles is appropriate for the AMLS function. The results of the pre-phase A study are discussed
A Compositional Approach for Schedulability Analysis of Distributed Avionics Systems
This work presents a compositional approach for schedulability analysis of
Distributed Integrated Modular Avionics (DIMA) systems that consist of
spatially distributed ARINC-653 modules connected by a unified AFDX network. We
model a DIMA system as a set of stopwatch automata in UPPAAL to verify its
schedulability by model checking. However, direct model checking is infeasible
due to the large state space. Therefore, we introduce the compositional
analysis that checks each partition including its communication environment
individually. Based on a notion of message interfaces, a number of message
sender automata are built to model the environment for a partition. We define a
timed selection simulation relation, which supports the construction of
composite message interfaces. By using assume-guarantee reasoning, we ensure
that each task meets the deadline and that communication constraints are also
fulfilled globally. The approach is applied to the analysis of a concrete DIMA
system.Comment: In Proceedings MeTRiD 2018, arXiv:1806.09330. arXiv admin note: text
overlap with arXiv:1803.1105
Research and technology goals and objectives for Integrated Vehicle Health Management (IVHM)
Integrated Vehicle Health Management (IVHM) is defined herein as the capability to efficiently perform checkout, testing, and monitoring of space transportation vehicles, subsystems, and components before, during, and after operational This includes the ability to perform timely status determination, diagnostics, and prognostics. IVHM must support fault-tolerant response including system/subsystem reconfiguration to prevent catastrophic failures; and IVHM must support the planning and scheduling of post-operational maintenance. The purpose of this document is to establish the rationale for IVHM and IVHM research and technology planning, and to develop technical goals and objectives. This document is prepared to provide a broad overview of IVHM for technology and advanced development activities and, more specifically, to provide a planning reference from an avionics viewpoint under the OAST Transportation Technology Program Strategic Plan
Ethernet - a survey on its fields of application
During the last decades, Ethernet progressively became the most widely used local area networking (LAN) technology. Apart from LAN installations, Ethernet became also attractive for many other fields of application, ranging from industry to avionics, telecommunication, and multimedia. The expanded application of this technology is mainly due to its significant assets like reduced cost, backward-compatibility, flexibility, and expandability. However, this new trend raises some problems concerning the services of the protocol and the requirements for each application. Therefore, specific adaptations prove essential to integrate this communication technology in each field of application. Our primary objective is to show how Ethernet has been enhanced to comply with the specific requirements of several application fields, particularly in transport, embedded and multimedia contexts. The paper first describes the common Ethernet LAN technology and highlights its main features. It reviews the most important specific Ethernet versions with respect to each application fieldâs requirements. Finally, we compare these different fields of application and we particularly focus on the fundamental concepts and the quality of service capabilities of each proposal
The Hidden Human Factors in Unmanned Aerial Vehicles
In April 2006, an Unmanned Aerial Vehicle crashed near Nogales, Arizona. This incident is of interest because it triggered one of the most sustained studies into the causes of failure involving such a vehicle. The National Transportation Safety Board together with the US Customs and Border Protection agency under the Department of Homeland Security worked to identify lessons learned from this mishap. The crash at Nogales is also of interest because it illustrates an irony of Unmanned Aircraft Systems operations; the increasing reliance on autonomous and unmanned operations is increasing the importance of other aspects of human-system interaction in the cause of major incidents. The following pages illustrate this argument using an accident analysis technique, Events and Causal Factors charting, to identify the many different ways in which human factors contributed to the loss of this Predator B aircraft
Assurance Benefits of ISO 26262 compliant Microcontrollers for safety-critical Avionics
The usage of complex Microcontroller Units (MCUs) in avionic systems
constitutes a challenge in assuring their safety. They are not developed
according to the development requirements accepted by the aerospace industry.
These Commercial off-the-shelf (COTS) hardware components usually target other
domains like the telecommunication branch. In the last years MCUs developed in
compliance to the ISO 26262 have been released on the market for safety-related
automotive applications. The avionic assurance process could profit from these
safety MCUs. In this paper we present evaluation results based on the current
assurance practice that demonstrates expected assurance activities benefit from
ISO 26262 compliant MCUs.Comment: Submitted to SafeComp 2018: http://www.es.mdh.se/safecomp2018
Combining SysML and AADL for the design, validation and implementation of critical systems
The realization of critical systems goes through multiple phases of specification, design, integration, validation, and testing. It starts from high-level sketches down to the final product. Model-Based Design has been acknowledged as a good conveyor to capture these steps. Yet, there is no universal solution to represent all activities. Two candidates are the OMG-based SysML to perform high-level modeling tasks, and the SAE AADL to perform lower-level ones, down to the implementation. The paper shares an experience on the seamless use of SysML and the AADL to model, validate/verify and implement a flight management system
- âŠ