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2016-09-27
Technical Paper
2016-01-8012
Daniel E. Williams, Amine Nhila, Kenneth Sherwin
A large percentage of commercial vehicles transport freight on our interstate highway system. These vehicles spend the vast majority of their duty cycle at high speed maintaining a lane. As steering is integrated into ADAS, objective performance measures of this most common mode of commercial vehicle operation will be required. Unfortunately in the past this predominant portion of the commercial vehicle duty cycle was overlooked in evaluating vehicle handling. This lanekeeping mode of operation is also an important, although less significant portion of the light vehicle duty cycle. Historically on-center handling was compromised to achieve acceptable low speed efforts. With the advent of advanced active steering systems, this compromise can be relaxed. Objective measures of lanekeeping are developed and performance of various advanced steering systems is quantified in this important operating mode.
2016-09-27
Technical Paper
2016-01-8013
Marius Feilhauer, Juergen Haering PhD, Sean Wyatt
The way to autonomous driving is closely connected to the possibility of verifying and validating Advanced Driver Assistance Systems (ADAS), as it is one of the main challenges to achieve secure, reliable and therewith socially accepted self-driving cars. Hardware-in-the-Loop (HiL) based testing methods offer the great advantage of validating components and systems in an early stage of the development cycle and it is an established process in automotive industry. When validating ADAS using HiL test benches, there are different barriers and conceptual difficulties engineers have to face: How to pipe simulated signals into multiple sensors including Radar, Ultrasonic, Video or Lidar? How to combine classical physical simulations, e.g. vehicle dynamics, with sophisticated three-dimensional, GPU-based environmental simulations? In this article, we present current approaches of how to master these challenges and provide guidance by showing the advantages and drawbacks of each approach.
2016-09-27
Technical Paper
2016-01-8111
Hiral Haria, Monika Ivantysynova
With the need for improvement in the fuel economy along with reduction in emissions due to stringent regulations, powertrain hybridization has become the focal point of research for the automotive sector. Hydraulic hybrids have progressively gained acceptance due to their high power density and low component costs relative to their electric counterpart and many different architectures have been proposed and implemented on both on and off-highway applications. The most commonly used architecture is the series hybrid which offers great flexibility for implementation of power management strategies. But the direct connection of the high pressure accumulator to the system often results in operation of the hydraulic units in high pressure and low displacement mode. However, in this operating mode the hydraulic units are highly inefficient. Also, the accumulator renders the system highly compliant and makes the response of the transmission sluggish.
2016-09-27
Technical Paper
2016-01-8033
Guoying Chen
According to the vehicle’s driving conditions, electronically controlled air suspension (ECAS) systems can adjust not only the stiffness and damping of the suspension but also the height of vehicle body, so that better ride comfort and handling stability will be achieved, which can’t be realized by traditional passive suspension. This paper presents a design and implementation of ECAS controller for vehicle. The controller is aimed at adjusting the static and dynamic height of the vehicle. To exactly track the height of the vehicle and satisfy the control demand of air suspension, a height sensor decoding circuit based on the inductance sensor is designed. Based on it, a new height control algorithm is adopted to achieve rapid and precise control of vehicle height. In order to verify the functions of the controller, we construct a test bench whose excitation source is provided by hydraulic system.
2016-09-27
Technical Paper
2016-01-8122
Jiaqi Xu, Hwan-Sik Yoon, Jae Y. Lee, Seonggon Kim
A neural network-based computer vision system is developed to estimate position of an excavator manipulator in real time. A camera is used to capture images of a manipulator, and the images are used to train a neural network. Then, the trained neural network can estimate the position of the excavator manipulator in real-time. To study the feasibility of the proposed system, an excavator simulator with a webcam is used. The simulation results show that the developed neural network-based computer vision system can estimate the position of the excavator manipulator with an acceptable accuracy.
2016-09-27
Technical Paper
2016-01-8104
Ryo Yamaguchi, Hiromichi Nozaki
In this study, we devised the steering assistance control that feedback of the external information from the laser sensor. We have created the emergency avoidance assistance control program by the obstacle detection in the first one, and the cornering assistance control program by the white line detection to second. Improvement in safety by these driving support can be expected. The effect of the created program was to understand by the driving simulator. In addition, we understand the synergistic effect of these steering assist program and chassis control (camber angle control, derivative steering assistance control). In the emergency avoidance assist by the obstacle detection, it made it possible to also be avoided for adding the handle operation at an early stage by the steering assistance in situations where manual operation collide by too late an obstacle avoidance handle operation.
2016-09-27
Technical Paper
2016-01-8130
giorgio malaguti, Massimiliano Ruggeri, Luca Dariz, Michele selvatici
Automotive industry compartment is undertaking a massive technology revolution. ADAS systems and infotainment promise to change the way that customers mean travel and transportation radically, through several use cases. The key enabling technologies for this trend are Ethernet and its newly standardized physical layer, IEEE 802.3bw 100BASE-T1 (a.k.a. BroadR-Reach). From an architectural point of view, the evolution of the applications that rely on Automotive Ethernet resembles in many ways the evolution that the IT has had in the last decades. In the IT world, increased throughput and computational power to the end-user enabled technologies like multimedia streaming; scalability and availability requirements, together with the increased complexity of IT infrastructure, led to the “Anything as a Service” paradigm and Software Defined Networks.
2016-09-27
Technical Paper
2016-01-8105
Shengguang Xiong, Gangfeng Tan
Path planning system which is one of Driver Assistance systems can calculate the shortest driving distance paths and estimate driving time according to the road information which is provided by information source. Traditional path planning system calculated the driving paths through Dijsktra algorithm or A* algorithm, only considering the road information which is provided by electronic map. It is not safe enough for the running vehicle because of the insufficient account of vehicle performances as well as the driver‘s driving strategies. This study based on Dijsktra algorithm, comprehensive considering vehicular active safety constraints of roads information, traffic condition, vehicle performances and the driver's driving characteristics to optimize the Dijsktra algorithm. Then path planning system would calculate the optimal driving paths which would satisfy the safety requirements of the vehicle.
2016-09-20
Technical Paper
2016-01-2059
Rolf Loewenherz, Virgilio Valdivia-Guerrero, Daniel Diaz Lopez, Joshua Parkin
Auto transformer rectifier units (ATRUs) are commonly used in aircraft applications such as electric actuation for harmonic mitigation due to its high reliability and relative low cost. However, those components and the magnetic filter components associated to it are major contributors to the overall size and weight of the system. Optimization of the magnetic components is essential in order to minimize weight and size, which are major market drivers in aerospace industry today. This requires knowledge of the harmonic content of the current. This can be obtained by simulation, but the process is slow. In order to enable fast and efficient design space exploration of optimal solutions, an algebraic calculation process is proposed in this paper for multi-pulse ATRUs (e.g. 12-pulse and 18-pulse rectifiers), starting from existing solution proposed for 6 pulse rectifier in the literature.
2016-09-20
Technical Paper
2016-01-2034
Tobias Kreitz, Frank Thielecke
The aviation industry is facing major challenges due to increased environmental requirements that are driven by economic constraints. For this reason, guidelines like "Flightpath 2050", the official guide of European aviation, call for significant reductions in pollutant emissions. The concept of the "More Electric Aircraft" offers promising perspectives to meet these demands. A key-enabler for this concept is the integration of new technologies on board of the next generation of civil transportation aircraft. Examples are electro-mechanical actuators for primary flight controls or the fuel cell technology as innovative electrical energy supply system. Due to the high complexity and interdisciplinary, the development of such systems is an equally challenging and time-consuming process. To support the classical development process, a continuous model-based approach for the design and test of complex aircraft systems is currently developed at the Hamburg University of Technology.
2016-09-20
Technical Paper
2016-01-2028
Maher A. Hasan, Eric Walters, Michael Boyd, Jason Wells, Jon Zumberge, Chad Miller
Increasing system complexity along with ever tighter integration between subsystems necessary to meet increasing performance demands of modern aerospace platforms can give rise to subsystem interactions that adversely affect overall system performance. The standard approach of utilizing dynamic modeling, simulation, and analysis (MS&A) to study these interactions is often inadequate to capture all effects of interest due to the assumptions required to make the modeling feasible and integrated simulations computationally tractable. As such, Hardware-in-the-loop (HIL) testing, with part of the system being emulated using real-time simulation models, is being increasingly utilized in addition to MS&A in order to study interactions that are unknown a priori or cannot be adequately captured using MS&A alone.
2016-09-20
Technical Paper
2016-01-2031
Michal Sztykiel, Steven Fletcher, Patrick Norman, Stuart Galloway, Graeme Burt
There is a well-recognized need for robust simulation tools to support the design and evaluation of future More-Electric Engine and Aircraft (MEE/MEA) design concepts. Design options for these systems are increasingly complex, and normally include multiple power electronics converter topologies and machine drive units. In order to identify the most promising set of system configurations, large number of existing technology variants need to be rapidly evaluated. This paper will describe a method of MEE/MEA system design with the use of a newly developed transient modelling, simulation and testing tool aimed at accelerating the identification process of optimal components, testing novel technologies and finding key solutions at an early development stage. The developed tool is a Matlab/Simulink library consisting of functional sub-system units, which can be rapidly integrated to build complex system architectures.
2016-09-20
Technical Paper
2016-01-1990
Nisha Kondrath, Nathaniel Smith
In aerospace applications, it is important to have efficient, small, affordable, and reliable power conversion units with high power density to supply a wide range of loads. Use of wide-band gap devices, such as Silicon Carbide (SiC) and Gallium Nitride (GaN) devices, in power electronic converters is expected to reduce the device losses and needs for extensive thermal management systems in power converters, as well as facilitate high-frequency operation, thereby reducing the passive component sizes and increasing the power density. A performance comparison of state-of-the art power devices in a 10 kW full-bridge buck converter operating in continuous conduction mode (CCM) and at switching frequencies above 100 kHz will be presented in this manuscript. Power devices under consideration will include Si IGBT with Si antiparallel diodes, Si IGBT with SiC antiparallel diodes, Si MOSFETs, SiC MOSFETs, and enhancement-mode GaN transistors.
2016-09-20
Technical Paper
2016-01-1987
Mingming Yin, Serhiy Bozhko, Seang Shen Yeoh
The paper will deal with the control design for an electric generation system which for future aircrafts. The future on-board systems are expected to be more efficient, safer, simpler in servicing and easier in maintenance. As a result, many existing hydraulic and pneumatic power driven systems are being replaced by their electrical counterparts. This trend is known as a move towards the More-Electric Aircraft (MEA). As a result, a large number of new electrical loads have been introduced in order to power many primary functions including actuation, de-icing and anti-icing, cabin air-conditioning, and engine start. Therefore electric power generation systems have a key role in supporting this technological trend. The state-of-the-art generation technology typically employs a three-stage wound-field synchronous machine. Advances in modern power electronics now allow the developers to consider including other machine types within the S/G.
2016-09-20
Technical Paper
2016-01-2014
Jonathan M. Rheaume, Charles Lents
The United Technologies Research Center has investigated a hybrid electric aircraft propulsion system for a commercial single aisle aircraft. The propulsion system features twin Geared Turbo Fan (GTF) engines in which each low speed spool is assisted by a 2,500 HP electric motor during takeoff and climb. During cruise, the aircraft is powered solely by the turbine engines which are sized for efficient operation during this mission phase. A survey of state of the art energy storage options was conducted. Battery, supercapacitor, and flywheel metrics were collected from the literature including Specific Energy (Wh/kg), Volumetric Energy Density (Wh/L), Power Density (W/kg), Cost ($/kWh), and Number of Cycles. Energy storage in fuels with converters was sized for comparison including fuel cells (both proton exchange membrane and solid oxide operating on hydrogen or on jet fuel) and a turbogenerator (jet fuel or LNG).
2016-09-20
Technical Paper
2016-01-1985
Fei Gao, Serhiy Bozhko, Patrick Wheeler
The paper will deal with the problem of establishing a desirable power sharing in multi-feed electric power system for future More-Electric Aircraft (MEA) platforms. The MEA is one of the major trends in modern aerospace engineering aiming for reduction of the overall aircraft weight, operation cost and environmental impact. Electrical systems are employed to replace existing hydraulic, pneumatic and mechanical loads. Hence the onboard installed electrical power increases significantly and this results in challenges in the design of Electrical Power Systems (EPS). One of the key paradigms for future MEA EPS architectures assumes high-voltage dc distribution with multiple sources, possibly of different physical nature, feeding the same bus(es). In our study we investigate control approaches to guarantee that the total electric load is shared between the sources in a desirable manner.
2016-09-20
Technical Paper
2016-01-1982
Michelle Bash, Steven Pekarek, Jon Zumberge
The cost and complexity of aircraft power systems often limits the ability to evaluate system performance using fully integrated aircraft hardware. As a result, evaluations are typically performed using emulators to mimic components or subsystems. As an example, aircraft generation systems are often tested using an emulator that consists of a bank of resistors that are switched to represent the power draw of one or more actuators. The limitation of this approach is that the switched resistive load falls short of representing the dynamic load characteristics of aircraft actuators or other power electronic loads, and thus the true integrated performance cannot be evaluated. In this research, consideration is given to modern emulators that use power electronics and digital controls to obtain wide bandwidth control of power, current, or voltage.
2016-09-20
Technical Paper
2016-01-1991
Syed J. Khalid
Engine bleed and power extraction are required by the aircraft to operate the various onboard subsystems which are necessary for the proper functioning of the aircraft. These extractions are parasitic for engine performance and operation. The engine companies make large investments in technology to achieve a couple of percent in engine efficiency. These gains can be quickly negated if bleed and power extraction are not judiciously managed for minimizing the amounts of extractions. Permission has been obtained from Boeing to use their public domain information on subsystem architecture to articulate the message in this paper. Help from Boeing and from Specific Range Solutions Ltd of Canada in the preparation of this paper is acknowledged. The paper will first quantify the detrimental effects of bleed and power extraction on engine performance and operation using the proven GasTurb 12 performance software. The engine modelled is similar to a modern transport aircraft turbofan.
2016-09-20
Technical Paper
2016-01-2029
Rolf Loewenherz, Francisco Gonzalez-Espin, Laura Albiol-Tendillo, Virgilio Valdivia-Guerrero, Ray Foley
The present work targets a Modelica-based holistic model and simulation approach. The targeted example considers a three phase converter which is divided into the control domain, the converter electrical and thermal domains (based on losses calculation), the heat transfer domain the electromechanical domain (motor and pump) and the fluid dynamics. In this paper, only the control, converter (electrical) and converter (thermal/losses) are described in detail, while the other domains are yet to be explored in future investigation. An averaged model is utilised for the electrical domain of the three phase converter, and a power balance method is used for linking the DC and AC sides. The thermal domain focuses in determining the converter losses by deriving the analytical equations of the space vector modulation to derive a function for the duty cycle of each converter leg.
2016-09-20
Technical Paper
2016-01-2030
Jon Zumberge, Michael Boyd, Raul Ordonez
Cost and performance requirements are driving military and commercial systems to highly integrated, optimized systems which require more sophisticated, highly complex controls. To realize benefits of those complex controls and make confident decisions, the validation of both plant and control models becomes critical. To quickly develop controls for these systems, it is beneficial to develop plant models and determine the uncertainty of those models to predict performance and stability of the control algorithms. A process of model and control algorithm validation for a dc-dc boost converter circuit based on acceptance sampling is presented here. The validation process described in this paper is based on MIL-STD 3022 with emphasis on requirements settings and the testing process. The key contribution of this paper is the process for model and control algorithm validation specifically a method for decomposing the problem into model and control algorithm validation stages.
2016-09-20
Technical Paper
2016-01-1981
Luis C. Herrera, Bang-Hung Tsao
One of the main challenges in the power systems of future aircraft is the capability to support pulsed power loads. The high rise and fall times of these loads along with their high power and negative impedance effects will have an undesirable impact on the stability and dc bus voltage quality of the power system. For this reason, studying ways to mitigate these adverse effects are needed for the possible adoption of these type of loads. One of the technologies which can provide benefits to the stability and bus power quality is Energy Storage (ES). This ES is designed with the capability to supply high power at a fast rate. In this paper, the management of the ES to mitigate the effects of pulsed power loads in an aircraft power system is presented. First, the detailed nonlinear model of the power network with pulsed power loads is derived. Due to the large size of this model, a model order reduction is performed using a balanced truncation.
2016-09-20
Technical Paper
2016-01-2027
Brett Robbins, Kevin J. Yost, Jon Zumberge
The next-generation of more electric aircraft (MEA) will rely heavily on multiple generators and energy storage to service a mix of constant power and resistive loads. This increase in system complexity, coupled with strict physical and performance requirements, necessitates the need for model-based system engineering (MBSE). As such, the validation of the component models is critical for the development process of MBSE. While it is not uncommon to develop/test component models with uncertainty studies combined with educated assumptions for the model parameters, the experimental hardware tests provide an important and effective means to validate the component models and quantify the variability of the model parameters. The Air Force Research Laboratory (AFRL) Intelligent Power program has procured numerous 40 kVA, 400 Hz, brushless synchronous generators at various stages of their life cycle.
2016-09-20
Technical Paper
2016-01-2042
Chad N. Miller, Michael Boyd
This paper introduces a method for conducting experimental hardware in the-loop (xHIL) in which an advanced power emulator (APE) is used to emulate an electrical load on an electrical power system (EPS). The emulator, in this case, is commanded using an advanced real-time target which can leverage CPUs and field programmable gate arrays (FPGA) to meet strict real-time execution requirements. The paper will be broken into three challenge problems (1) develop a solution to target behavioral level models to an advanced computational device (2) develop a high-bandwidth power emulation capability and (3) integrate these two solutions into an xHIL experiment. Challenge (1) will be addressed by targeting a behavioral level model of a brushless DC motor drive with a pulsedwidth modulated inverter to a real-time system. The results of the real-time model will be compared to that of a non-real-time gold standard.
2016-09-20
Technical Paper
2016-01-1978
Philippe Coni, Sylvain Hourlier, Xavier Servantie, Laurent Laluque, Aude Gueguen
A 3D Stereoscopic Head-Up Display (HUD) using direct projection on a transparent screen is presented. Symbol incrustation in conformity with the landscape is performed by using simulated collimation offering a large eye-box, in excess of conventional HUD. By opposition with existing 3D system, using polarizing or active glasses, not designed for a see through system, spectral glasses are used, providing both 3D image displaying and green laser attack protection.
2016-09-20
Technical Paper
2016-01-2015
Rory Telford, Catherine Jones, Patrick Norman, Graeme Burt
Mass and efficiency are key performance indicators for the development and design of future electric power systems (EPS) for more-electric aircraft (MEA). However, to enable consideration of high-level EPS architecture design trades, there is a requirement for modelling and simulation based analysis to support this activity. The predominant focus to date has been towards the more detailed aspects of analysis, however there is also a significant requirement to be able to perform rapid high-level trades of candidate architectures and technologies. Such a capability facilitates a better appreciation of the conflicting desires to maximise availability and efficiency in candidate MEA architectures, whilst minimising the overall system mass. It also provides a highly valuable and quantitative assessment of the systemic impact of new enabling technologies being considered for MEA applications.
2016-09-20
Technical Paper
2016-01-2058
Thibaut Billard, Cedric Abadie, Bouazza Taghia
Rationalization of energy sources aboard aircraft and improvements in more electric technologies are pushing the aeronautic industry to meet the all-electric aircraft challenge. As a result, onboard power has been steadily increasing, reaching 1MW for B787. This paradigm shift towards more electrical aircraft architectures results in a higher risk of electrical discharges events such as gaseous breakdown, electrical arc and partial discharges. The latter phenomena being an important cause of concerns for component manufacturers as well as aircraft integrator because environmental, electrical stresses and cycling are, associated with mass reduction, all pointing in the direction of a higher likeliness of partial discharges events. The aim of this study is to characterize the partial discharge inception voltage, with the aforementioned constraints in mind, on aeronautic motor and its component in a representative environment.
2016-09-20
Technical Paper
2016-01-2061
Andrew S. Babel, Parag Kshirsagar, Suman Dwari
In aerospace actuator applications electric machines are demanded to produce large static and dynamic torque while being constrained with stringent weight and volume restrictions. Among various types of electrical machines, Permanent Magnet (PM) Machines with strong rare earth magnets, offer the highest torque and power density with low rotor inertia. This paper presents design and study of three high-density PM machine topologies from the perspective of aerospace actuator applications. The machine topologies are compared with three key metrics for the same current density: torque per unit mass, torque per unit squared rotational inertia, and torque per unit volume. Such thorough comparison of these three candidates PM machine topologies for aerospace actuator application is not reported in available publications. Key requirements of specific actuation application, such as torque density and active length, are taken into account for the design.
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