Display:

Results

Viewing 151 to 180 of 22050
2015-09-27
Technical Paper
2015-28-0157
Kamalesh Hemant Kankariya
A Micro grid is a part of a distribution network embedding multiple distributed generation systems (mostly non-conventional renewable energy sources like photo voltaic panels, small wind turbines etc.) and storage systems with local loads, which can be disconnected from the upstream network under emergency conditions or as planned. The Micro grid concept naturally arose to cope with the penetration of renewable energy sources, which can be realistic if the final user is able to generate, store, control and manage part of the energy that it will consume. The power connection between Micro grid components can be done through a direct current (DC) link or an alternating current (AC) link. Application of individual distributed generators can cause as many problems as it may solve. A better way to realize the emerging potential of distributed generation is to take a system approach which views generation and associated loads as a subsystem or a “Micro grid”.
2015-09-27
Technical Paper
2015-28-0158
Naveen PR
The paper involves the architecture of Hybrid electric vehicle aimed especially for the design and development of the hybrid powered formula car with optimized targets such as Fuel economy, better acceleration with satisfactory top speed of around 140 kph. The required characteristics of both the electric vehicle and ICE vehicle and the design has been going so far with the following concepts such as regenerative braking, Smaller ICE for less fuel consumption, potential balance, stability in terms of weight distribution and with less electrical losses. This Paper also involves the study of steady power and dynamic power load decompositionand its effect over the driving characteristics of the vehicle. Various configurations are iterated for the targeted vehicle such as series- parallel as wellas various complex configurations in which the solvation is brought up by the discrete simulation Methods using MATLAB Simulink, The Mathworks Inc.
2015-09-27
Technical Paper
2015-28-0164
Riaz Ahamed, Koorma Rao Vavilapalli, Abhijit V.P., Clement Jones, Suraj Gopalakrishnan
In design of electric traction motor, temperature rise in the motor plays a crucial role in determining the performance characteristics of the motor. The operating life of any motor is dependent on its primary and secondary insulation capability. The life of insulation depends on losses in a motor which contributes to the temperature rise. This paper presents the encapsulation (potting) process carried out on traction motor with different epoxy based potting materials and mass production feasibility are also focused. The encapsulation process affords better heat transfer from the coils to the frame enhancing winding rigidity, create total protection against moisture and prevent corrosion thereby improving the performance and life of the traction motors in applications such as electric vehicles. This process enables entire stator winding to be filled with encapsulation material without air bubbles to avoid thermal hotspots.
2015-09-27
Technical Paper
2015-28-0161
Karthikeyan Ethirajan
Rolling resistance contributes ~8% impact on energy efficiency of an automobile. This paper emphasises on how power consumption in an electric vehicle architecture is minimized by reducing rolling resistance through optimization of design parameters in front axle unitised bearing. Optimum bearing design selection can result upto 10% lesser power consumption hence increasing vehicle efficiency. Suitable testing results and calculations establish the claims in reduction of power consumption. The effect of higher energy losses due to rolling resistance are prominent in Electric-Vehicles as compared to IC-Engine cars due to significantly lower power-train losses which overshadow rolling resistance losses in conventional cars.
2015-09-27
Technical Paper
2015-28-0162
Fabian Ruecker, Ilka Bremer
Electric vehicle (EV) lifetime strongly depends on the intensity of battery degradation. Simulation models that include battery ageing mechanisms are used to benchmark these influences on total depreciation during one charging process. A nonlinear programming algorithm has been used to optimize EV charging. An energy price signal is included and the total operational costs for EV charging are minimized. It can be shown, that the interior point algorithm evaluates the optimal solution to charge every single vehicle with desired battery energy capacity and is suitable for prediction purposes in fleet applications. This is shown for a case study incorporating 22 EVs for delivery services.
2015-09-27
Technical Paper
2015-28-0168
Rahul Kumar Singh
Atmega16 is a 8-bit micro-controller which has many function like timer, interrupt, ADC, etc. Atmega16 has one 16-bit timer and two 8-bit timer. By hardware PWM, we can only control 4 servos by using 2 8-bit timers and splitting 16bit timer in 2 8-bit timers. A 8-bit timer gives an approximate resolution of 14 degrees per count which is not satisfactory for high precision robotic application. This project aims at extending the control of servos upto 30 for Atmega16 by bit-banging. The main advantage of this servo controller is that it uses 16-timer which gives it a resolution of about .045 degrees per count which is a good resolution. The Servo Controller uses a heavy call of interrupts. It receives data in form of ID of servo and Angle given to it ending with a end of transmission data.Data is sent to Servo Controller by the uses of UART protocol. Because of that instead of converting all 32 GPIO pins into producing PWM only 30 pin are only used for PWM generation.
2015-09-27
Technical Paper
2015-28-0169
Riaz Ahamed, Sathish Kumar
EVs will play a very significant role in meeting the challenges of global warming and depletion of oil resources. EVs use 50 percent less energy and cause zero pollution. High-efficiency, silent running and low cost transmission is the critical objective for electric vehicles. The objective of this paper concern the design and optimization of gearbox for electric vehicles. Two stage reduction gearbox with ratio i1 and i2, coupled with traction motor certainly meets the operating range of city cars. This transmission can adopt different gear ratios easily by changing one gear pair. To reduce the overall noise level, more attention given to the design of the casings. The casings are made of general purpose high strength casting Aluminium alloy LM25, which also reduces the overall weight of the transmission. Optimized rib provided in the casing to achieve the required stiffness to withstand the vibrations and modal frequency.
2015-09-27
Journal Article
2015-01-2668
Ulrich Ungethuem, Dirk Simon
The hydraulic brake products like brake calipers, master cylinders and boosters are the foundation of today complex vehicle brake systems. The state of the art application leads very often to an individual design, due to the fulfillment of customer requirements within the available installation space. Also the enormous pressure on cost and time require optimized design processes. Therefore Continental developed the product configuration software CoBra. Within this software tool, the engineering is able to react very fast on demands. Starting with the brake sizing parameters and the customer interface definition, CoBra supports the design engineer to select the necessary components and positioning them accordingly, considering the actual design standards. The data based configuration software collects all necessary design parameters and provides an export to parametric CAD start up models.
2015-09-22
Book
Ian K. Jennions, Samir Khan, Paul Phillips, Chris Hockley
Today, we are all strongly dependent on the correct functioning of technical systems. They fail, and we become vulnerable. Disruptions due to degradation or anomalous behavior can negatively impact safety, operations, and brand name, reducing the profitability of all elements of the value chain. This can be tolerated if the link between cause and effect is understood and remedied. Anomalous behavior, which indicates systems or subsystems not acting in accordance with design intent, is a much more serious problem. It includes unwanted system responses and faults whose root cause can’t be properly diagnosed, leading to costly, and sometimes unnecessary, component replacements. The title No Fault Found: The Search for the Root Cause was developed to propose solutions to this technical and business challenge, which has become less and less acceptable to the commercial aviation industry globally.
2015-09-20
Book
This is the electronic format of the Journal.
2015-09-15
Technical Paper
2015-01-2470
Subramanian Ramasamy, Roberto Sabatini, Alessandro Gardi
Cooperative and non-cooperative Detect-and-Avoid (DAA) functions are key enablers for Remotely Piloted Aircraft System (RPAS) to safely and routinely access all classes of airspace. In this paper state-of-the-art cooperative and non-cooperative DAA sensor/system technologies for manned aircraft and RPAS are reviewed and the associated multi-sensor data fusion techniques are discussed. A DAA system architecture is presented based on Boolean Decision Logics (BDL) for selecting non-cooperative and cooperative sensors/systems including both passive and active Forward Looking Sensors (FLS), Traffic Collision Avoidance System (TCAS) and Automatic Dependent Surveillance – Broadcast (ADS-B). After elaborating the DAA system processes, the key mathematical models associated with both non-cooperative and cooperative DAA functions are presented.
2015-09-15
Technical Paper
2015-01-2456
Roberto Sabatini, Terry Moore, Chris Hill
The integration of Global Navigation Satellite System (GNSS) integrity augmentation functionalities in Unmanned Aerial Vehicles (UAV) Detect-and-Avoid (DAA) architectures has the potential to provide an integrity-augmented DAA solution suitable for cooperative and non-cooperative scenarios. In this paper, we evaluate the opportunities offered by this integration, proposing a novel approach that maximizes the synergies between Avionics Based Integrity Augmentation (ABIA) and UAV cooperative/non-cooperative DAA architectures. In the proposed architecture, the risk of collision is evaluated by setting a threshold on the Probability Density Function (PDF) of a Near Mid-Air Collision (NMAC) event over the separation area in both cooperative and non-cooperative cases.
2015-09-15
Technical Paper
2015-01-2482
Riko Bornholdt, Tobias Kreitz, Frank Thielecke
Abstract For the shift to more-electric aircraft systems, the system specific design paradigm has to be dissolved and the allocation of functions has to be reconsidered. Including more degrees of freedom within the architecture design process for aircraft systems could lead to beneficial architecture concepts. However, new methods for conceptual systems design are required, to cope with the significantly increasing number of potential architecture variations to be evaluated. Within this paper, the GENESYS methodology enabling the design and evaluation of numerous architecture variations will proposed. The methodology consists of several modules, each dedicated to a specific process step of conceptual aircraft system design. Initially, a method for the design-independent analysis of the aircraft level functions and the identification of requirements for the aircraft systems will be illustrated.
2015-09-15
Technical Paper
2015-01-2619
Karl-Otto Strömberg, Stefan Borgenvall, Mohamed Loukil, Bertrand Noharet, Carola Sterner, Magnus Lindblom, Orjan Festin
LWPT (Lightweight Production Technology) is today a well-established technology in the automotive industry. By introducing light weight fixtures manufactured from Carbon Fiber Reinforced Plastics (CFRP), new production processes have been developed in the automotive industry. This has resulted in increased productivity, reduced investment costs and increased flexibility. The next step is to introduce this technology in the aerospace industry. Aircraft components are complex and large products having small tolerance windows. Fixtures manufactured in FRP materials allow integration of health monitoring sensors directly into the structure. This means that information on displacements can be recorded both when the fixture is stationary, while work is being performed, as well as in a pulsed production line when the fixture is moving between the assembly stations.
2015-09-15
Technical Paper
2015-01-2497
George Nicholas Bullen
Abstract The introduction of composite materials onto air vehicles has complicated the traditional hole/countersink assessment criteria due its finished-part thickness variability; softer and dissimilar properties than the metallic substructure where it is mounted and attached; and the increased attention to other acceptance criteria such as fiber tear, fiber pull, and moisture propagation in the hole that degrades fastener capability. The addition of composite materials further complicates the assembly process by adding a boundary layer of liquid shim or sealant between the composite piece (usually a skin) and the substructure. Current hole inspection systems are absent the ability to assess the interior condition of the composite hole such as fiber tear, damage to the liquid shim, and debris or burrs between the multiple stacks of dissimilar material.
2015-09-15
Journal Article
2015-01-2499
Perla Maiolino, Richard A. J. Woolley, Atanas Popov, Svetan Ratchev
Abstract The assembly and manufacture of aerospace structures, in particular legacy products, relies in many cases on the skill, or rather the craftsmanship, of a human operator. Compounded by low volume rates, the implementation of a fully automated production facility may not be cost effective. A more efficient solution may be a mixture of both manual and automated operations but herein lies an issue of human error when stepping through the build from a manual operation to an automated one. Hence the requirement for an advanced automated assembly system to contain functionality for inline structural quality checking. Machine vision, used most extensively in manufacturing, is an obvious choice, but existing solutions tend to be application specific with a closed software development architecture.
2015-09-15
Technical Paper
2015-01-2408
Hitoshi Oyori, Noriko Morioka, Tsuyoshi Fukuda
Abstract This paper will propose a novel power generating system concept including an auxiliary, backup and emergency power source. Existing aircraft employ an auxiliary power unit (APU) and a ram air turbine (RAT) for power generation besides aero-engine generators. An APU works prior to starting propulsion on the ground and as a backup power plant during flight. The RAT is activated due to the need to maintain the essential systems in the case of an emergency situation. Both systems are optimized on conventional aircraft in which hydraulic, pneumatic and electric systems are supplied for control and equipment. Although a conventional aircraft needs hydro pumps and air compressors, the coming of a new era of more-electric architecture for aircraft and propulsion will be the stimulus to improve aircraft systems [1]. In more-electric aircraft, the authors focus on the low-pressure spool generation system of aero-engines.
2015-09-15
Technical Paper
2015-01-2412
Tao Yang, Serhiy Bozhko, Greg Asher
This paper aims to develop a general functional model of multi-pulse Auto-Transformer Rectifier Units (ATRUs) for More-Electric Aircraft (MEA) applications. The ATRU is seen as the most reliable way readily to be applied in the MEA. Interestingly, there is no model of ATRUs suitable for unbalanced or faulty conditions at the moment. This paper is aimed to fill this gap and develop functional models suitable for both balanced and unbalanced conditions. Using the fact that the DC voltage and current are strongly related to the voltage and current vectors at the AC terminals of ATRUs, a generic functional model has been developed for both symmetric and asymmetric ATRUs. The developed functional models are validated through simulation and experiment. The efficiency of the developed model is also demonstrated by comparing with corresponding detailed switching models. The developed functional model shows significant improvement of simulation efficiency, especially under balanced conditions.
2015-09-15
Technical Paper
2015-01-2455
Roshen Jay Jaswantlal, Piergiovanni Marzocca, Rafael Palacios
Abstract The implementation of Synthetic Jet Actuators (SJAs) on Unmanned Aerial Vehicles (UAVs) provides a safe test-bed for analysis of improved performance, in the hope of certification of this technology on commercial aircraft in the future. The use of high resolution numerical methods (i.e. CFD) to capture the details of the effects of SJAs on flows and on the hosting lifting surface are computationally expensive and time-consuming, which renders them ineffective for use in real-time flow control implementations. Suitable alternatives include the use of Reduced Order Models (ROMs) to capture the lower resolution overall effects of the jets on the flow and the hosting structure. This research paper analyses the effects of SJAs on aircraft wings using a ROM for the purpose of determining the unsteady aerodynamic forces modified by the presence of the SJAs. The model developed is a 3D unsteady panel code where the jets are represented by source panels.
2015-09-15
Technical Paper
2015-01-2404
Catherine E. Jones, Karen Davies, Patrick Norman, Stuart Galloway, Graeme Burt, Michael Armstrong, Andrew Bollman
Abstract Distributed electrical propulsion for aircraft, also known as turbo-electric distributed propulsion (TeDP), will require a complex electrical power system which can deliver power to multiple propulsor motors from gas turbine driven generators. To ensure that high enough power densities are reached, it has been proposed that such power systems are superconducting. Key to the development of these systems is the understanding of how faults propagate in the network, which enables possible protection strategies to be considered and following that, the development of an appropriate protection strategy to enable a robust electrical power system with fault ride-through capability. This paper investigates possible DC protection strategies for a radial DC architecture for a TeDP power system, in terms of their ability to respond appropriately to a DC fault and their impact on overall system weight and efficiency.
2015-09-15
Technical Paper
2015-01-2447
John Low
Abstract The development of the Electrical Wire Interconnection System, or EWIS, for today's advanced aircraft is one of the most complicated engineering activities around. In addition to having to respond to very high rates of change during development, the aircraft are continually evolving in electronic and electrical content through their entire lifecycle. Relatively new mandates, such as the CFR Part 25 Subpart H EWIS, have put additional demands on aircraft OEMs and their key suppliers, forcing companies to reassess their design practices and methodologies. This paper investigates how a systems engineering approach to the development of the electrical wiring systems can enable and facilitate a more efficient EWIS development and maintenance methodology.
2015-09-15
Technical Paper
2015-01-2448
Steve Trythall
Abstract Meeting aerospace configuration control mandates involves a host of issues such as data access control, configuration context and release management, just to name a few factors. Currently, many companies rely on the existing product lifecycle management (PLM) environment to identify and sort out issues during data release. This has proven to be inadequate. In this paper, it is postulated that new design tools employing automation can save a great deal of time when meeting these mandates and eliminate errors as well. The tools are based on the model-based development (MBD) process, which puts much more emphasis on the actual data instead of simply drawings. This paper explores how leading aerospace original equipment manufacturers (OEMs) are adopting new capabilities for the designers during the development process in an effort to mitigate errors related to data inconsistencies.
2015-09-15
Technical Paper
2015-01-2522
Mirko Jakovljevic, Jan Radke, Perry Rucker
Abstract VPX, as a switched fabric, supports the design of advanced integrated systems using technologies such as deterministic Ethernet. Deterministic Ethernet can be used in backplane and backbone applications. In cases where functional interrelationships and Ethernet network bandwidth sharing is deterministic and all logical links among critical function have configurable quality of service with guaranteed timing, the complexity challenges in design of advanced integrated architectures can be much simpler to handle and mitigate. VPX switches in 3/6U format with ARINC664 and SAE AS6802 services enable deterministic integration of many critical functions hosted on common embedded computing and networking resources. Both ARINC664 (asynchronous real-time) and SAE AS6802 (synchronous hard real-time), as Layer 2 enhancements, do not affect existing Ethernet services.
2015-09-15
Technical Paper
2015-01-2527
Mirko Jakovljevic, Jan Radke
Abstract Integrated modular architectures and IMA reduce the physical complexity of electronic architecture by integrating many functions on common embedded resources. As the reduction of physical complexity means that the embedded resources are shared by many functions, the logical complexity of system configuration, functional alignment and resource sharing increases significantly. Modern integrated embedded platforms are designed for parameter-based architecture design and integration. IMA is not only a set of platform components, networking and computing devices and configurable middleware and platform abstraction layers. Integrated Architectures and IMA require mature design and verification tools, and a well-defined design and integration methodology are required to avoid expensive and error-prone manual analyses and configuration tasks. Therefore, integrated architectures cannot be separated from design methodologies and processes.
2015-09-15
Technical Paper
2015-01-2528
Srikanth Gururajan
Abstract In recent years, there has been an increase in the use of Unmanned Aerial Systems (UAS) in the civilian sector for various purposes. As these platforms are constrained in terms of payload and capacity, they are typically equipped with a minimal sensor suite and the use of redundant sensors is uncommon. This research effort describes the design and simulation of a Neural Network (NN) based fault tolerant flight control approach for sensor and actuator failures, implemented on a parallel and distributed computational architecture. The inter process communication is implemented using BSD sockets and Message Passing Interface (MPI). For the purpose of the sensor failure detection, identification and accommodation (SFDIA) task, it is assumed that the pitch, roll and yaw rate gyros onboard the aircraft are without physical redundancy.
2015-09-15
Technical Paper
2015-01-2533
Philippe Coni, Frederic Merino, Frederic Renaud
Abstract Projected capacitive touchscreen (PCAP) became popular thanks to the introduction of the Apple iPhone, iPad and iPod. Electrical field generated for touch detection is known to be impaired by external fields, for example Cold Cathode Fluorescent Lamp, USB charger or AMLCD driving. Commercial product shall live with this issue, but the high intensity radiated field required for avionics application is several orders of magnitude higher than required for commercial product. In such an environment, standard touchscreens could have hazardous behavior. Thanks to the unique 20 years' experience on projected capacitive technology (Aircraft fighter), we designed a new projected capacitive touchscreen, based on a ruggedized touch controller and dedicated ASIC, able to operate in extreme electromagnetic environment.
2015-09-15
Technical Paper
2015-01-2535
Steven Donald Ellersick, Bill Reisenauer, Mickey Jacobson, Newel Stephens
Abstract The past twenty years have seen tremendous changes in the Avionics display and flight deck lighting due to the application of solid-state LED (light emitting diode) light sources and LCDs (liquid crystal displays). These advances significantly benefit the customer and pilot users when integrated correctly. This paper discusses recommended practices and guidance given in SAE ARP 4103 for modern Avionics flight deck lighting systems to satisfy the end user and obtain certification. SAE ARP 4103 Flight Deck Lighting for Commercial Transport Aircraft has recently been revised to keep up with the Avionics state-of-the-art and add clarification where needed. ARP 4103 contains recommended Avionics flight deck lighting design and performance criteria to ensure prompt and accurate readability and visibility, color identification and discrimination of needed information under all expected ambient lighting and electrical power conditions. For additional details, see the actual ARP 4103.
2015-09-15
Technical Paper
2015-01-2537
Sylvain Hourlier
Abstract The efficiency of the glass cockpit paradigm has faded away with the densification of the aeronautical environment. Today's problem lies with “non-defective aircraft” monitored by “perfectly trained crews” still involved in fatal accidents. One explanation is, at crew level, that we have reached a system complexity that, while acceptable in normal conditions, is hardly compatible with human cognitive abilities in degraded conditions. The current mitigation of such risk still relies on the enforcement through intensive training of an ability to manage extremely rare (off-normal) situations. These are explained by the potential combination of failures of highly complex systems with variable environment & with variable humans.
2015-09-15
Technical Paper
2015-01-2536
Rinky Babul Prasad, Vinukonda Siddartha
Abstract Recent years have seen a rise in the number of air crashes and on board fatalities. Statistics reveal that human error constitutes upto 56% of these incidents. This can be attributed to the ever growing air traffic and technological advancements in the field of aviation, leading to an increase in the electronic and mechanical controls in the cockpit. Accidents occur when pilots misinterpret gauges, weather conditions, fail to spot mechanical faults or carry out inappropriate actions. Currently, pilots rely on flight manuals (hard copies or an electronic tablet) to respond to an emergency. This is prone to human error or misinterpretation. Also, a considerable amount of time is spent in seeking, reading, interpreting and implementing the corrective action. The proposed augmented head mount virtual assist for the pilot eliminates flight manuals, by virtually guiding the pilot in responding to in-flight necessities.
2015-09-15
Technical Paper
2015-01-2542
Alejandro Murrieta-Mendoza, Ruxandra Mihaela Botez, Roberto S Félix Patrón
Abstract Flight trajectory optimization algorithms reduce flight cost and fuel consumption, thereby reducing the polluting emissions released to the atmosphere. Ground teams and avionics equipment such as the Flight Management System evaluate different routes to minimize flight costs. The optimal trajectory represents the flight plan given to the crew. The resulting flight plan contains waypoints and weather information such as the wind speed and direction and the temperature for each waypoint. The flight plan is normally introduced manually into the Flight Management System. In this paper, genetic algorithms were applied to the waypoints available in a flight plan to find the altitudes that minimize total fuel consumption, taking into account the cruise-climb and cruise-descent steps' costs. The genetic algorithms emulate the evolution process through a predefined number of generations.
Viewing 151 to 180 of 22050

Filter