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Viewing 61 to 90 of 16558
2017-09-19
Journal Article
2017-01-2036
William Schley
Abstract Of all aircraft power and thermal loads, flight controls can be the most challenging to quantify because they are highly variable. Unlike constant or impulsive loads, actuator power demands more closely resemble random processes. Some inherent nonlinearities complicate this even further. Actuation power consumption and waste heat generation are both sensitive to input history. But control activity varies considerably with mission segment, turbulence and vehicle state. Flight control is a major power consumer at times, so quantifying power demand and waste heat is important for sizing power and thermal management system components. However, many designers sidestep the stochastic aspects of the problem initially, leading to overly conservative system sizing. The overdesign becomes apparent only after detailed flight simulations become available. These considerations are particularly relevant in trade studies comparing electric versus hydraulic actuation.
2017-09-19
Technical Paper
2017-01-2048
Bryan Shambaugh, Patrick Browning
Abstract In this research, the magnetoplasmadynamic (MPD) effects of applying a toroidal magnetic field around an ionized exhaust plume were investigated to manipulate the exhaust profile of the plasma jet under near vacuum conditions. Tests for this experiment were conducted using the West Virginia University (WVU) Hypersonic Arc Jet Wind Tunnel. A series of twelve N52 grade neodymium magnets were placed in different orientations around a steel toroid mounted around the arc jet’s exhaust plume. Four different magnet orientations were tested in this experiment. Two additional configurations were run as control tests without any imposed magnetic fields surrounding the plume. Each test was documented using a set of 12 photographs taken from a fixed position with respect to the flow. The photographic data was analyzed by comparing images of the exhaust plume taken 10, 20, and 30 seconds after the plasma jet was activated.
2017-09-19
Technical Paper
2017-01-2110
Ashutosh Kumar Jha, Prakash Choudhary
Abstract The complexity of software development is increasing unprecedentedly with every next generation of aircraft systems. This requires to adopt new techniques of software design and verification that could optimize the time and cost of software development. At the same time these techniques need to ensure high quality of software design and safety compliance to regulatory guidelines like DO-178C [1] and its supplements DO-330[2] and DO-331[3]. To arrive at new technologies one has to evaluate the alternate methods available for software design by developing models, integration of models, auto-code generation, auto test generation and also the performance parameters like time, effort, reuse and presentation needs to be evaluated. We have made an attempt to present summary of alternate design concept study, and edge of MBD over other design techniques.
2017-09-19
Technical Paper
2017-01-2108
Denis Buzdalov, Alexey Khoroshilov
Different modelling techniques intended to deal with complexity of modern IMA systems are widely used now. Models can be used to help developers to lay out relevant information structurally. They can also be used to perform different formal analyses on machine-readable models like schedulability analysis, network load checks, WCET for software parts, FTA and FMEA and etc. For some kinds of analyses, special models are created on different stages of development. We suppose that reuse of models for different aspects and development stages is generally a good thing. In some cases it allows to reduce costs on development process; also it allows to make preservation of consistency between models more automatic. We are aware that using the same model for different stages or aspects can cause additional cost in the model maintenance. In this paper we are trying to make a step to further (including practical) research on this topic.
2017-09-19
Technical Paper
2017-01-2109
Kiran Thupakula
Abstract Airport environments consist of several moving objects both in the air and on the ground. In air moving objects include aircraft, UAVs and birds etc. On ground moving objects include aircraft, ground vehicles and ground personnel etc. Detecting, classifying, identifying and tracking these objects are necessary for avoiding collisions in all environmental situations. Multiple sensors need to be employed for capturing the object shape and position from multiple directions. Data from these sensors are combined and processed for object identification. In current scenario, there is no comprehensive traffic monitoring system that uses multisensor data for monitoring in all the airport areas. In this paper, for explanation purposes, a hypothetical airport traffic monitoring system is presumed that uses multiple sensors for avoiding collisions.
2017-09-19
Journal Article
2017-01-2114
Jann-Eve Stavesand, Sören Reglitz, Andreas Himmler
Abstract In the aerospace industry, methods for virtual testing cover an increasing range of test executions carried out during the development and test process of avionics systems. Over the last years, most companies have focused on questions regarding the evaluation and implementation of methods for virtual testing. However, it has become more and more important to seamlessly integrate virtual testing into the overall development process. For instance, a company’s test strategy might stipulate a combination of different methods, such as SIL and HIL simulation, in order to benefit from the advantages of both in the same test process. In this case, efforts concentrate on the optimization of the overall process, from test specification to test execution, as well as the test result evaluation and its alignment with methods for virtual testing.
2017-09-19
Technical Paper
2017-01-2112
Mirko Jakovljevic
A specific set of architecture design patterns and computational models, used in integrated modular architectures for commercial domains can be deployed in other avionics, automotive and transportation domains. With the combination of different deterministic Ethernet protocol capabilities and selective application of best practices on non-blocking models of computation and communication, with strong resource sharing, isolation/partitioning and fault detection mechanisms, it is possible to design open Ethernet-based architectures which can host non-critical/soft-time and critical (hard RT, real-time) functions, and at the same time can support incremental modernization, reuse, and upgrades at significantly reduced system complexity and lifecycle costs.
2017-09-19
Technical Paper
2017-01-2113
Michael Schultz
Abstract Passenger boarding is always part of the critical path of the aircraft turnaround: both efficient boarding and online prediction of the boarding progress are essential for a reliable turnaround progress. However, the boarding progress is mainly controlled by the passenger behavior. A fundamental scientific approach for aircraft boarding enables the consideration of individual passenger behaviors and operational constraints in order to develop a sustainable concept for enabling a prediction of the boarding progress. A reliable microscopic simulation approach is used to model the passenger behavior, where the individual movement is defined as a one-dimensional, stochastic, and time/space discrete transition process. The simulation covers a broad range of behaviors and boarding strategies as well as the integration of new technologies and procedures.
2017-09-19
Technical Paper
2017-01-2104
Marc Gatti
I Certification of a mono or multicore processor is going to request to demonstrate that we are able to master the determinism of the execution for all the applications which are going to be executed. Regarding the multicore we introduce a level of complexity to be managed regarding the execution of the application in parallel on each of the cores of the multicore processor whatever is the internal architecture of the processor. In an IMA context: This determinism is insured by the control of the WCET allowing defining a maximal boundary for all the accesses to all the services offered by the Operating System. The Platform Provider has no information about the applications which are going to be executed by his platform. In this condition the computation of a WCET on a multi-core, like it is done currently on a mono-core, will be realized by introducing constraints at the level of the internal functioning of the multi-core processor.
2017-09-19
Technical Paper
2017-01-2107
Thorsten Kiehl, Jan Philip Speichert, Ethan Higgins, Ralf God
Abstract For an “end-to-end passenger experience that is secure, seamless and efficient” the International Air Transport Association (IATA) proposes Near Field Communication (NFC) and a single token concept to be enablers for future digital travel. NFC is a wireless technology commonly utilized in Portable Electronic Devices (PEDs) and contactless smart cards. It is characterized by the following two attributes: a tangible user interface and secured short range communication. While manufacturers are currently adapting PED settings to enable NFC in the flight mode, the integration and use of this technology in aircraft cabins still remains a challenge. There are no explicit qualification guidelines for electromagnetic compatibility (EMC) testing in an aircraft environment available and there is a lack of a detailed characterization of NFC equipped PEDs.
2017-09-19
Technical Paper
2017-01-2101
Jon Barton Shields, Brian Peirce Barker
Abstract This paper discusses the merits, benefits and usage of autonomous key management (with implicit authentication) (AKM) solutions for securing Electronic Module to Electronic Module (i.e. ECUs, FCC, REUs, etc.) communication within air (and defense) vehicles and IoT applications; particularly for transmissions between externally exposed, edge Electronic Module sensors connected to Electronic Modules within the air (and defense) vehicle infrastructure. Specific benefits addressed include reductions of communication latency, implementation complexity, processing power and energy consumption. Implementation issues discussed include provisioning, key rotation, synchronization, re-synchronization, digital signatures and enabling high entropy.
2017-09-19
Technical Paper
2017-01-2103
Bernd Hirschler, Mirko Jakovljevic
Abstract Cybersecurity attacks exploit vulnerabilities related to the increased complexity and connectivity of critical infrastructure systems. This paper investigates the context and use of key security technologies, processes, challenges and use cases for the design of advanced integrated architectures with security, safety, and real-time performance considerations. In such architectures, deterministic Ethernet standards are used as a baseline for system integration in closed embedded systems or open mixed criticality systems. Security-informed safety development processes for integrated architectures are required to prevent catastrophic failures caused by environmental and cyber threats, due to expanding number of security vulnerabilities in complex and increasingly open systems. State-of-art safety/security processes for integrated systems in cross-industry environments are considered and similarities examined, for different types of integrated architectures.
2017-09-19
Technical Paper
2017-01-2121
Greg Parlier
The US Department of Defense (DoD) operates the most complex global supply chain in the world. However, effectively integrating production planning, maintenance operations, inventory systems, and distribution policies has been a persisting strategic challenge for the logistics enterprise supporting the DoD. Neither DoD nor the Congressional Budget Office has been able to establish a well-defined linkage between Operations and Maintenance resource funding levels and the resulting readiness of military units. For nearly three decades the Government Accountability Office has attributed these inadequacies to poor demand forecasting, ineffective inventory management, and inadequate strategic planning. To address these persisting problems the US Army established the project to Transform Army Supply Chains (TASC) in order to investigate the nature, causes, and consequences of demand uncertainty and supply variability.
2017-09-19
Technical Paper
2017-01-2123
Violet Leavers
Abstract The need to maintain aircraft in remote, harsh environments poses significant challenges. For example, in desert assignments or on-board carrier vessels where frequent rotation of staff with variable levels of skill and experience requires condition monitoring equipment that is not only robust and portable but also user friendly and requiring a minimum of training and skill to set up and use correctly. The mainstays of any on-site aircraft maintenance program are various fluid and particulate condition monitoring tests that convey information about the current mechanical state of the system. In the front line of these is the collection and analysis of wear debris particles retrieved from a component’s lubricating or power transmission fluid or from magnetic plugs. It is standard practice within the specialist laboratory environment to view and image wear debris using a microscope.
2017-09-19
Technical Paper
2017-01-2117
Dirk H. Martinen, Marc Lagalaye, Julien Pfefferkorn, Jean Casteres
Abstract Currently, aircraft system Test Benches are often proprietary systems, specifically designed and configured for a dedicated System Under Test (SUT). Today, no standards for configuration, data communication, and data exchange formats are available for avionics Test Benches. This leads to high Test Bench development costs and redundant activities between aircraft system suppliers and airframers. In the case of obsolescence issues for test system components, it is very costly to replace the respective parts as a high integration and reconfiguration effort is required. In the scope of an R&T project, involving several test system suppliers and aircraft system suppliers as well as Airbus as an aircraft manufacturer, a generic and modular architecture for an open test environment is under development. A further goal of the Virtual and Hybrid Testing Next Generation (VHTNG) research project is to prepare a set of open standards for the interfaces to this architecture.
2017-09-19
Technical Paper
2017-01-2118
Prashant S Vadgaonkar, Diptar banik
Abstract Avionics industry is moving towards more electric & lightweight aircrafts. Electromagnetic effects becomes significantly challenging as materials starts moving towards composite type. Traditional methods for controlling EMC will not be sufficient. This shift increases the complexity of in-flight hardware elements for EMI/EMC control. This paper discusses the need for EMI/EMC Control and brings out the analysis & applicability of various EMI/EMC standards in aerospace, commercial and industrial electronic products, provides comparative study with respect to levels. The study include various sections of DO-160 and applicable guidelines for controlling EMI/EMC with respect to LRU (Line Replaceable Unit) & wire/cable harnesses. Also presents guidelines with respect to shielding of components, selection of components, grounding schemes, filter topologies and layout considerations.
2017-09-19
Journal Article
2017-01-2165
Christian Moeller, Hans Christian Schmidt, Philip Koch, Christian Boehlmann, Simon Kothe, Jörg Wollnack, Wolfgang Hintze
Abstract The high demand of efficient large scale machining operations by concurrently decreasing operating time and costs has led to an increasing usage of industrial robots in contrast to large scaled machining centers. The main disadvantage of industrial robots used for machining processes is their poor absolute accuracy, caused by the serial construction, resilience of gearings and sensitivity for temperature changes. Additionally high process forces that occur during machining of CFRP structures in aerospace industry lead to significant path errors due to low structural stiffness of the robot kinematic. These errors cannot be detected by means of motor encoders. That is why calibration processes and internal control laws have no effect on errors caused by elastic deformation. In this research paper an approach for increasing the absolute accuracy of an industrial milling robot with help of a Laser Tracker system during machining tasks will be presented.
2017-09-19
Technical Paper
2017-01-2160
Ferdinand Spek, Maarten Weehuizen, Ilja Achterberg
Abstract In new aircraft programs, systems’ functionality is increasingly becoming integrated into modular avionics. Controllers may not be delivered by the systems supplier so this trend creates a new interface between systems and controllers. A functional software specification is therefore needed to facilitate the building of the software by the controller supplier. In the case of an ECS system controller, the hardware was obtained from different suppliers and a software functional specification was needed for the controller supplier. To be able to design and verify the system functionality, an integrated ECS simulation model was created which coupled the thermodynamics of the aircraft and ECS system to the controller actions. The model also included functionality to simulate sensor noise and component failures. The thermodynamic model was created in Matlab/Simulink and consisted of a combination of direct programming as well as data on a Flowmaster model for the bleed system.
2017-09-19
Technical Paper
2017-01-2020
Michael Croegaert
Abstract Modern military aircraft platforms are using more and more power which results in an ever increasing power density (SWaP). This in turn, generates more heat that has to be dissipated from the instrument panel and cockpit of the aircraft. Complicating this further is that the use of structural composites which are not efficient conductors of heat and the mission requirements of small heat signatures. Therefore alternative means of extracting the heat from the avionics systems must be used. Liquid cooled systems have the advantage over air cooled systems of a much higher heat transfer rate and the fact that the heat can be transported a significant distance from the source. Liquid cooled avionics have their own challenges as well.
2017-09-19
Technical Paper
2017-01-2030
Benjamin Cheong, Paolo Giangrande, Patrick Wheeler, Pericle Zanchetta, Michael Galea
Abstract High power density for aerospace motor drives is a key factor in the successful realization of the More Electric Aircraft (MEA) concept. An integrated system design approach offers optimization opportunities, which could lead to further improvements in power density. However this requires multi-disciplinary modelling and the handling of a complex optimization problem that is discrete and nonlinear in nature. This paper proposes a multi-level approach towards applying random heuristic optimization to the integrated motor design problem. Integrated optimizations are performed independently and sequentially at different levels assigned according to the 4-level modelling paradigm for electric systems. This paper also details a motor drive sizing procedure, which poses as the optimization problem to solve here. Finally, results comparing the proposed multi-level approach with a more traditional single-level approach is presented for a 2.5 kW actuator motor drive design.
2017-09-19
Technical Paper
2017-01-2060
Joseph Dygert, Patrick Browning, Magdalena Krasny
Abstract The dielectric barrier discharge (DBD) has seen significantly increased levels of interest for its applications to various aerodynamic problems. The DBD produces stable atmospheric-pressure non-thermal plasma with highly energetic electrons and a variety of ions and neutral species. The resulting plasma often degrades the dielectric barrier between the electrodes of the device, ultimately leading to actuator failure. Several researchers have studied a variety of parameters related to degradation and time-dependent dielectric breakdown of various polymers such as PMMA or PVC that are often used in actuator construction. Many of these studies compare the degradation of these materials to that of borosilicate glass in which it is claimed that there is no observable degradation to the glass. Recent research at West Virginia University has shown that certain actuator operating conditions can lead to degradation of a glass barrier and can ultimately result in failure.
2017-09-19
Technical Paper
2017-01-2061
Andrea Cravana, Gerardo Manfreda, Enrico Cestino, Giacomo Frulla, Robert Carrese, Piergiovanni Marzocca
Abstract An accurate aeroelastic assessment of powered HALE aircraft is of paramount importance considering that their behaviour contrasts the one of conventional aircraft mainly due to the use of high aspect-ratio wings with distributed propulsion systems. This particular configuration shows strong dependency of the wing natural frequencies to the propulsion distribution and operating conditions. Numerical and experimental investigations are carried out to better understand the behaviour of flexible wings, focusing on the effect of distributed electric propulsion systems. Several configurations are investigated, including a single propulsion system using an engine pod (a weight with embedded electric motor, a propeller, and the wing-attached structure) installed at selected spanwise positions, and configurations with two and three propellers.
2017-09-19
Technical Paper
2017-01-2065
Sebastian Bandycki, Michele Trancossi, Jose Pascoa
Abstract This paper presents a comparison between different hypotheses of propulsion of a spherical UAS. Different architectures have been analyzed assessing their specific aerodynamic, energetic, and flight mechanics features. The comparison has been performed assuming the robustness of flight control in different wind conditions, defining for each the specific operative ranges, mission profiles, and energy assessment. An effective energy assessment and comparison against a commercial UAS has been produced. Even if the paper considers a preliminary simplified configuration, it demonstrates clearly to be competitive against traditional quadcopters in a predefined reference mission.
2017-09-19
Technical Paper
2017-01-2063
Patrick Browning, Bryan Shambaugh, Joseph Dygert
Abstract The dielectric barrier discharge (DBD) has been studied significantly in the past two decades for its applications to various aerodynamic problems. The most common aerodynamic applications have been stall/separation control and boundary layer modification. Recently several researchers have proposed utilizing the DBD in various configurations to act as viable propulsion systems for micro and nano aerial vehicles. The DBD produces stable atmospheric-pressure non-thermal plasma in a thin sheet with a preferred direction of flow. The plasma flow, driven by electrohydrodynamic body forces, entrains the quiescent air around it and thus develops into a low speed jet on the order of 10-1 to 101 m/s. Several researchers have utilized DBDs in an annular geometric setup as a propulsion device. Other researchers have used them to alter rectangular duct flows and directional jet devices. This study investigates 2-D duct flows for applications in micro plasma thrusters.
2017-09-19
Technical Paper
2017-01-2115
Gilberto Burgio, Leonardo Mangeruca, Alberto Ferrari, Marco Carloni, Virgilio Valdivia-Guerrero, Laura Albiol-Tendillo, Parithi Govindaraju, Marcel Gottschall, Olaf Oelsner, Sören Reglitz, Jann-Eve Stavesand, Andreas Himmler, Lionel Yapi
Abstract Multi-physics interactions between structural, electrical, thermal, or hydraulic components and the high level of system integration, characteristic of new aircraft designs, is increasing the complexity of both design and verification processes. Therefore the availability of tools, supporting integrated modelling, simulation, optimization and testing across all stages of aircraft design remains a critical challenge. This paper presents some results of the project MISSION (Modelling and Simulation Tools for Systems Integration on Aircraft). It is a collaborative task being developed under the European Union Clean Sky 2 Program, which is a public-private partnership bringing together aeronautics industrial leaders and public research organizations based in Europe. The first levels of integration of different models and tools proposed in the MISSION framework will be presented, along with simulation results.
2017-09-19
Technical Paper
2017-01-2085
Sergey Lupuleac, Nadezhda Zaitseva, Margarita Petukhova, Julia Shinder, Sergey Berezin, Valeriia Khashba, Elodie Bonhomme
Abstract The paper is devoted to the simulation of A320 wing assembly on the base of numerical experiments carried out with the help of ASRP software. The main goal is to find fasteners’ configuration with minimal number of fastening elements that provides closing of admissible initial gaps. However, for considered junction type initial gap field is not known a priori though it should be provided as input data for computations. In order to resolve this problem the methodology of random initial gap generation based on available results of gap measurements is developed along with algorithms for optimization of fasteners' configuration on generated initial gaps. Presented paper illustrates how this methodology allows optimizing assembly process for A320 wing.
2017-09-19
Technical Paper
2017-01-2111
Andrew Loveless, Christian Fidi, Stefan Wernitznigg
Abstract Over the last couple decades, there has been a growing interest in incorporating commercial off-the-shelf (COTS) technologies and open standards in the design of human-rated spacecraft. This approach is intended to reduce development and upgrade costs, lower the need for new design work, eliminate reliance on individual suppliers, and minimize schedule risk. However, it has not traditionally been possible for COTS solutions to meet the high reliability and fault tolerance requirements of systems implementing critical spacecraft functions. Byzantine faults are considered particularly dangerous to such systems because of their ability to escape traditional means of fault containment and disrupt consensus between system components. In this paper, we discuss the design of a voting protocol using Time-Triggered Ethernet capable of achieving data integrity in the presence of a single Byzantine fault.
2017-09-17
Technical Paper
2017-01-2514
Wei Han, Lu Xiong, Zhuoping Yu, Haocheng Li
Abstract BBW (Brake-by-wire) can increase the electric and hybrid vehicles performance and safety. This paper proposes a novel mechatronic booster system, which includes APS (active power source), PFE (pedal feel emulator), ECU (electronic control unit). The system is easily disturbed when the system parameters and the outside conditions change. The system performance is weakened. The cascade control technique can be used to solve the problem. This paper develops an adaptive cascade optimum control (ACOC) algorithm based on the novel mechatronic booster system. The system is divided into main loop and servo loop, both of them are closed-loop system. The servo-loop system can eliminate the disturbance which exists in the servo loop. So the robustness of the cascade control system is improved than which of the general closed-loop control system. Different control object is respectively chosen. The control-oriented mathematical model is designed.
2017-09-17
Technical Paper
2017-01-2500
Bo Huang, Wanyang Xia, Gangfeng Tan, Longjie Xiao, Zongsong Wang
Abstract Head-up Display (HUD) system can avoid drivers’ distraction on dashboard and effectively reduce collisions caused by emergency events, which is gradually being realized by researchers around the world. However, the current HUD only displays information like speed, fuel consumption, other information like acceleration and braking can’t be displayed yet. This research will use the indicator symbol‘s color and position change to remind drivers to brake or accelerate. Drivers can do driving operation timely and accurately. The system has the advantages of safety, intuition and real-time. The vehicle safe speed is calculated according to the road parameters, like adhesion coefficient and slope, and vehicle parameters, such as vehicle mass and centroid. Then, the appropriate braking operations are obtained by combining the vehicle driving state.
2017-09-04
Technical Paper
2017-24-0003
Andreas Sidorow, Vincent Berger, Ghita Elouazzani
Abstract Gasoline engines have typically a waste gate actuator to control the boost pressure. The electrification of the vehicle and combustion engine components leads to new challenges of application of electric actuators in engine components, like turbochargers, which are faced with relatively high ambient temperatures. Another challenge is a simulation and prediction of the mechanical load on the actuator and kinematic components at different application scenarios, which can help to find the optimal solution which fulfills the durability, controllability, etc. targets. This paper deals with a physical dynamic model of an electric waste-gate actuator and kinematic components. The modeling includes a thermal, electrical and mechanical parts of the turbocharger control system and is validated on test-bench and engine measurements including pulsation effects.
Viewing 61 to 90 of 16558