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2015-12-03 ...
  • December 3-4, 2015 (8:30 a.m. - 4:30 p.m.) - Troy, Michigan
  • May 11-12, 2016 (8:30 a.m. - 4:30 p.m.) - Tysons, Virginia
Training / Education Classroom Seminars
Engineers are taught to create designs that meet customer specifications. When creating these designs, the focus is usually on the nominal values rather than variation. Robustness refers to creating designs that are insensitive to variability in the inputs. Much of the literature on robustness is dedicated to experimental techniques, particularly Taguchi techniques, which advocate using experiments with replications to estimate variation. This course presents mathematical formulas based on derivatives to determine system variation based on input variation and knowledge of the engineering function.
2015-09-15
Technical Paper
2015-01-2394
Rudolf Neydorf
In the experimental and computer modeling of statics and dynamics of aircrafts have difficulties relating to their essential nonlinearity. This is due to the fact that the aerodynamic effects of the interaction complex aircraft designs or their models with air environment generate abrupt changes of the character of the some dependencies. Aerodynamic coefficients in the model of interaction can be obtained only or by full-scale tests or by computer simulations. Therefore, the construction of mathematical models of the objects is associated with the mathematical processing of the points of the experimental data. In this case, the experimentally obtained dependence is usually essentially nonlinear up to piecewise, or even discontinuous nature. Approximation of such dependencies, even with the use of spline functions, is very difficult and is associated with large errors.
2015-09-15
Technical Paper
2015-01-2392
Matthew Marino, Alessandro Gardi, Roberto Sabatini
This paper gives the concepts and mathematically models required for the development of the Multi Objective Trajectory Optimization (MOTO) functionalities to be implemented into the next generation of ATM system. MOTO algorithms are introduced whereby data from various sources are utilized to optimize flight paths for various user defined objectives. The algorithms require digital resources of weather, aircraft data, meteorological maps and air traffic. These will be used in conjunction with various mathematical models to compute trajectories that minimize various objectives such as fuel, emissions and operational cost. The automated 4D trajectory computation algorithms are restricted to single flight level to not violate the current layered vertical air route structure for the cruise phase of flight.
2015-09-15
Technical Paper
2015-01-2390
Georges Ghazi, Ruxandra Botez, Joseph Messi Achigui
During aircraft development, mathematical models are elaborated from our knowledge of fundamental physical laws. Those models are used to gain knowledge in order to make decisions in all development stages. As engine model is one of the most important items in aircraft simulation, this paper presents a methodology to obtain a generic technique that can be used to predict the net thrust value of the engines for the Cessna Citation X. The proposed methodology is divided in two steps. The first step is focused on the estimation of the net thrust value in steady state. The goal of this section is to obtain a model that can predict the maximum thrust of the turbofan engine at different flight conditions in terms of altitude and Mach number. To do this, semi-empirical equations available in the literature and the least squares method are used to identify the coefficients of the proposed model.
2015-09-15
Technical Paper
2015-01-2584
Andrew Dickerson, Ravi Rajamani, Mike Boost, John Jackson
Based on a advanced modeling approach, we are developing a system for estimating the remaining useful life (RUL) for Li-Ion batteries for aerospace applications. We begin with a set of functional requirements that are further translated to detailed system and maintenance specifications. We will show how this RUL calculator will be translated to actual algorithms and operating procedures inside a battery’s management unit. Test data will be used to validate the robustness and goodness in the predictions. We will also share plans for the future along with implications for certification of the system. This is important because batteries are governed by FAA regulations and are dispatch critical for certain applications.
2015-09-15
Technical Paper
2015-01-2477
Alessandro Gardi, Roberto Sabatini
A number of initiatives are aiming at assessing and reducing the impact of air transport on the environment. This extensive endeavour is soliciting a substantial evolution in the measurement of the environmental impacts and on the assessment of the effective gains attained by the R&D outcomes. Legislation is already being progressively extended in several countries to limit or penalise noise emissions, and analogous regulatory actions can be foreseen with respect to atmospheric pollutants. This research activity is developing laser-based Light Detection and Ranging (LIDAR) systems for characterisation of gaseous pollutants and particulate concentrations in high space and time resolutions. The employed measurement principle is based on Differential Absorption LIDAR technique, in a bistatic layout. After the initial feasibility study, two candidate bistatic system layouts have been proposed.
2015-09-15
Technical Paper
2015-01-2542
Alejandro Murrieta-Mendoza, Ruxandra Mihaela Botez, Roberto S Félix Patrón
Flight trajectory optimization algorithms reduce flight cost regardless of the aircraft technologies. Besides flight cost reduction, diminishing fossil fuel consumption leads to reducing polluting emissions. Ground teams and avionic equipment such as the flight management system seek for the routes that minimize the flight cost. The flight plan also contains the trajectory information in the form of waypoints to follow. This plan is provided to the pilot and is introduced into the flight management system. The flight plan contains as well weather information such as wind and temperature. In this paper, genetic algorithms were applied to the waypoints available in the flight plan to find the combination of altitudes that minimize the flight time and fuel burned. In the literature trajectories are normally taken from radar date, or the geodesic route between two points amongst others. Published waypoints are seldom used.
2015-07-15
Standard
J182_201507
This SAE Recommended Practice describes a procedure for locating the three-dimensional reference system on a motor vehicle as built.
2015-06-15
Technical Paper
2015-01-2153
David Serke, Michael King, Andrew Reehorst
In early 2015, a field campaign was conducted at the NASA Glenn Research Center in Cleveland, Ohio, USA. The purpose of the campaign is to test several prototype algorithms meant to detect the location and severity of in-flight icing (or icing aloft, as opposed to ground icing) within the terminal airspace. Terminal airspace for this project is currently defined as within 25 kilometers horizontal distance of the terminal, which in this instance is Hopkins International Airport in Cleveland. Two new and improved algorithms that utilize ground-based remote sensing instrumentation have been developed and were operated during the field campaign. The first is the ‘NASA Icing Remote Sensing System’, or NIRSS. The second algorithm is the ‘Radar Icing Algorithm’, or RadIA.
2015-06-15
Journal Article
2015-01-2220
Ji Xu, Guohua Sun, Tao Feng, Mingfeng Li, Teik Lim
Abstract This paper describes an active sound tuning (AST) system for vehicle powertrain response. Instead of simply aiming to attenuate cabin interior noise, AST system is capable of reshaping the powertrain response based on predetermined vehicle sound quality criteria. However, conventional AST systems cannot yield a balanced result over the broad frequency range when applied to powertrain noise. It is due to the fact that existing systems are typically configured with the filtered-x least mean square (FXLMS) algorithm or its modified versions, which has inherent frequency dependent convergence behavior due to large dynamic range of secondary path (the electro-acoustic path from the control speaker to the error microphone). Therefore, fast convergence can only be reached at the resonant frequencies.
2015-06-15
Journal Article
2015-01-2217
Guohua Sun, Tao Feng, JI Xu, Mingfeng Li, Teik Lim
Abstract Current powertrain active noise control (ANC) systems are not sufficient enough to track the fast engine speed variations, and yield consistent convergence speeds for individual engine order such that a balanced noise reduction performance can be achieved over a broad frequency range. This is because most of these ANC systems are configured with the standard filtered-x least mean squares (FxLMS) algorithm, which has an inherent limitation in the frequency-dependent convergence behavior due to the existence of secondary path model (electro-acoustic path from the input of control loudspeaker to the output of monitoring error microphone) in the reference signal path. In this paper, an overview is given first to compare several recently modified FxLMS algorithms to improve the convergence speed for harmonic responses such as eigenvalue equalization FxLMS (EE-FXLMS) and normalized reference LMS (NX-LMS) algorithms.
2015-06-15
Journal Article
2015-01-2218
Shuguang Zuo, Jun Zhang, Xudong Wu, Jiajie Hu, Guo Long
Abstract Blower is one of the main noise sources of fuel cell vehicle. In this paper, a narrowband active noise control (ANC) model is established based on adaptive notch filter (ANF) to control the high-frequency noise produced by the blower. Under transient conditions, in order to reduce the frequency mismatch (FM) of ANC for blower, a new Frequency Mismatch Filtered-Error Least Mean Square algorithm (FM-FELMS) is proposed to attenuate blower noise under transient conditions. According to the theoretical analysis and simulation, the proposed algorithm has an excellent noise reduction performance at relatively high blower speed. While for the low speed working condition, the Normalized Least Mean Square (NLMS) algorithm is applied to attenuate noise. The two algorithms could be jointly utilized to control the blower noise actively.
2015-04-14
Technical Paper
2015-01-1729
Chenle Sun, Zhe Wang, Zhaolei Yin, Tong Zhang
Abstract The linear internal combustion engine-linear generator integrated system (LICELGIS) is a generating unit with high power density, high efficiency and low emission for the range-extended electric vehicle. The LICELGIS starts with the linear generator, which shows the advantages of speed, efficiency and emission reduction, as well as the prerequisite to guarantee the steady operation of the system. This paper focuses on the reversing control method and the energy utilization efficiency in the starting process of the LICELGIS. Pursuant to the starting requirements of the linear internal combustion engine, the fewest driving cycle and the evaluation index are obtained. Meanwhile, the velocity tracking mode and the position tracking mode is proposed for the control of the starting force reversing. The motions of the starting process under two control method are comparatively analyzed, indicating that the former has a high efficiency, while the latter is more likely to achieve.
2015-04-14
Technical Paper
2015-01-0428
Sida Li, Xiaowu Yang, Bruce Minaker, Xiaojin (Shine) Lan, Mark Villaire
Abstract An accurate bushing model is vital for vehicle dynamic simulation regarding fatigue life prediction. This paper introduces the Advanced Bushing Model (ABM) that was developed in MATLAB® environment, which gives high precision and fast simulation. The ABM is a time-domain model targeting for vehicle durability simulation. It dynamically captures bushing nonlinearities that occur on stiffness, damping and hysteresis, through a time-history-based fitting technique, compensated with frequency dependency functionality. Among the simulated and test-collected bushing loads, good correlations have been achieved for elastomer bushings and hydraulic engine mounts and validated with a random excitation signal. This ABM model has been integrated into a virtual shaker table (from a parallel project) as the engine mount model to simulate the mount load, and has shown acceptable prediction on fatigue damage.
2015-04-14
Technical Paper
2015-01-0608
Gang Tang, Hengjia Zhu, Yunqing Zhang, Ying Sun
Abstract The vehicle ride comfort behavior is closely associated with the vibration isolation system such as the primary suspension system, the engine mounting system, the cab suspension system and the seat suspension system. Air spring is widely used in the cab suspension system for its low vibration transmissibility, variable spring rate and inexpensive automatic leveling. The mathematical model of the air spring is presented. The amplitude and frequency dependency of the air spring's stiffness characteristic is highlighted. The air spring dynamic model is validated by comparing the results of the experiment and the simulation. The co-simulation method of ADAMS and AMESim is applied to integrate the air spring mathematical model into the cab multi-body dynamic model. The simulation and ride comfort test results under random excitation are compared.
2015-04-14
Technical Paper
2015-01-0620
Manoj Mahala, Anindya Deb, Clifford Chou
Abstract Idealized mathematical models, also known as lumped parameter models (LPMs), are widely used in analyzing vehicles for ride comfort and driving attributes. However, the limitations of some of these LPMs are sometimes not apparent and a rigorous comparative study of common LPMs is necessary in ascertaining their suitability for various dynamic situations. In the present study, the mathematical descriptions of three common LPMs, viz. quarter, half and full car models, are systematically presented and solved for the appropriate response parameters such as body acceleration, body displacement, and, pitch and roll angles using representative passive suspension system properties. By carrying out a comparison of the three stated LPMs for hump-type road profiles, important quantitative insights, not previously reported in the literature, are generated into their behaviors so that their applications can be judicious and efficient.
2015-04-14
Technical Paper
2015-01-1629
Himadri Bushan Das, Simos A Evangelou, Samraj Jabez Dhinagar
The objective of this paper is to estimate characteristics parameters of two wheeler powertrain with simulated vehicle model. The evaluation is applied to define required characteristics for future motor integrated powertrain. The main parameters for the characteristics matrix are Fuel consumption and NOx gas emission. In the 1st phase of work, a mathematical model for the complete powertrain is developed using suitable modelling approach for different sub-modules of the complete system. The objectives of the model are, to simulate dynamic power-flow from the engine to wheel and to simulate NOx gas emission. The powertrain model consists of a carburetted spark ignition (S.I) engine and gear transmission system. The S.I engine model is capable of simulating dynamic torque output of engine as well as the NOx gas emission. The model is experimentally compared with available test data of production ready engine from TVS Motor Company, India.
2015-04-14
Technical Paper
2015-01-0190
Mostafa Anwar Taie, Ibrahim El-Faramawy, Mohamed Elmawazini
Abstract In embedded system software architectural design, the Real-Time (RT) behavior estimation needs special care and contains many technical challenges. Most of the current approaches depend on either the engineering judgment or the actual measurements that are performed during the integration-testing phase. Both approaches may cause errors that lead to violations in the RT constraints. Both approaches are not error proof and can yield to RT constraints violations discovered during simulation of RT architectural design or during product validation. Impact on project could even be a Central Processing Unit (CPU) change. In this work, Operating System (OS) process Execution Time (ET) is considered the basic element of RT architectural design. Each process ET is predicted based on previous software releases, using Machine Learning (ML) algorithms.
2015-04-14
Journal Article
2015-01-0480
Santosh Tiwari, Don Jones, Simon Xu
Abstract Response Surface Models are often used as a surrogate for expensive black-box functions during optimization to reduce computational cost. Often, the CAE analysis models are highly nonlinear and multi-modal. A response surface approximation of such analysis as a result is highly multi-modal; i.e. it contains multiple local optima. A gradient-based optimizer working with such a response surface will often converge to the nearest local optimum. There does not exist any method to guarantee a global optima for non-convex multi-modal functions. For such problems, we propose an efficient algorithm to find as many distinct local optima as possible. The proposed method is specifically designed to work in large dimensions (about 100 ∼ 1000 design variables and similar number of constraints) and can identify most of the locally optimal solutions in a reasonable amount of time.
2015-04-14
Journal Article
2015-01-0488
Andreea Elena Balau, Dennis Kooijman, Ignacio Vazquez Rodarte, Norbert Ligterink
Abstract This paper presents a methodology and tool that stochastically generates drive cycles based on measured data, with the purpose of testing and benchmarking light duty vehicles in a simulation environment or on a test-bench. The WLTP database, containing real world driving measurements, was used as input data. Consequently cycles that contain typical accelerations per velocity and road types are generated, such that these cycles are representative to real driving behavior. The stochastic drive cycle generator is developed in Matlab and is based on Markov processes. Two separate stochastic generators are used: one for generating the road type and one for generating the vehicle acceleration. First, a random road type profile is generated from the four different road types that are considered in the WLTP database: urban, rural, motorway and high-motorway, each of them with sub-road types based on different velocity bins.
2015-04-14
Technical Paper
2015-01-0502
Zhicheng Xu, Gangfeng Tan, Xingzhi Sun, Yongqiang Ge, Min Hua, Haobo Xu
Abstract For the thin ice on the road in winter, the traditional road deicing vehicle relies on mechanical and chemical methods for melting ice, which is inclined to damage the pavement and has insidious influence on environment. The thermal deicing vehicle has been adopted in recent years. Although the deicing method is available, the deicing efficiency is unacceptable while the energy consumption is huge. The study adopts the new idea of “bottom-to-top” for melting the intersection area between the road surface and the bottom ice layer by the microwave heating firstly and then cleaning them out using high pres. vapor cutting so as to save the cost of energy and enhance the traffic safety. First of all, the mathematical model of the melting process of the intersection of the pavement and the ice layer was established according to the microwave heating characteristics.
2015-04-14
Technical Paper
2015-01-1146
Matthew Barr, Krishnaswamy Srinivasan
Abstract In this paper, a new algorithm for the off-line estimation of wet clutch friction parameters is proposed for automotive transmissions, motivated by the usefulness of such an algorithm for diagnosing the condition of the clutch and transmission fluid in service. We assume that clutch pressure is measured, which is the case in dual clutch transmissions (DCT). The estimation algorithm uses measured rotational speeds and estimated accelerations at the input and output sides of a clutch, measured clutch pressures, and a simplified dynamic model of clutch friction to estimate the viscous and contact components of clutch friction torque. Coefficient of friction data is generated using the contact friction torque. A Stribeck friction model is fit to the data, and parameters in the model are then calculated by applying linear least squares estimation.
2015-04-14
Technical Paper
2015-01-1119
Guangqiang Wu, Lijun Wang
Abstract The traditional automotive torque converter (TC) is equipped with a single-blade stator, at the suction side of which there is an apparent boundary layer separation at stalling condition because of its large impending angle. The separation flow behind the suction side of stator blade is found to create large area of low-energy flow which blocks effective flow passage area, produces more energy losses, decreases impeller torque capacity and transmission efficiency. It is found effective to suppress the boundary layer separation by separating the original single-blade stator into a primary and a secondary part. The gap between them guides high-energy flow at the pressurized side of the primary blade to the suction side of the secondary one, which helps to make boundary layer flow stable. As a result, the impeller torque capacity and torque ratio at low-speed ratio increase tremendously at the cost of little drop of maximum efficiency.
2015-04-14
Technical Paper
2015-01-1109
Yulong Lei, Ke Liu, Yao Fu, Ge Lin, Bin Song
Abstract This investigation presents a methodology to develop and optimize shift process control strategy to improve shift quality as perceived by drivers during power-on upshift events for Dual Cultch Transmission (DCT) vehicles. As part of the first study, the main factors affecting shift quality during shifting process under typical working conditions are analyzed. And taking the power-on upshift as example, dynamic model of DCT shifting process is build. An Integrated control strategy is proposed for power-on upshift, which during torque phase slipping revolving speed controller is adapted to harmonically control two clutches power switching process, and during Inertial phase engine torque is regulated to synchronize with the value of target gear while holding the oncoming clutch pressure. Oncoming clutch oil pressure gradient in torque phase and engine torque reducing target decrement in inertial phase are chosen as controlled quantity.
2015-04-14
Journal Article
2015-01-0479
Hongyi Xu, Ching-Hung Chuang, Ren-Jye Yang
Abstract One of the major challenges in multiobjective, multidisciplinary design optimization (MDO) is the long computational time required in evaluating the new designs' performances. To shorten the cycle time of product design, a data mining-based strategy is developed to improve the efficiency of heuristic optimization algorithms. Based on the historical information of the optimization process, clustering and classification techniques are employed to identify and eliminate the low quality and repetitive designs before operating the time-consuming design evaluations. The proposed method improves design performances within the same computation budget. Two case studies, one mathematical benchmark problem and one vehicle side impact design problem, are conducted as demonstration.
2015-04-14
Technical Paper
2015-01-1182
Mehrdad Mastali Majdabadi Kohneh, Ehsan Samadani, Siamak Farhad, Roydon Fraser, Michael Fowler
Abstract Lithium-ion batteries (LIBs) are one of the best candidates as energy storage systems for automobile applications due to their high power and energy densities. However, durability in comparison to other battery chemistries continues to be key factor in prevention of wide scale adoption by the automotive industry. In order to design more-durable, longer-life, batteries, reliable and predictive battery models are required. In this paper, an effective model for simulating full-size LIBs is employed that can predict the operating voltage of the cell and the distribution of variables such as electrochemical current generation and battery state of charge (SOC). This predictive ability is used to examine the effect of parameters such as current collector thickness and tab location for the purpose of reducing non-uniform voltage and current distribution in the cell. It is identified that reducing the non-uniformities can reduce the ageing effects and increase the battery durability.
2015-04-14
Technical Paper
2015-01-1412
Xuan Zhou, Walter Niewoehner
Abstract The safe handling of complex and dense traffic situations is a basic pillar of road safety. Advanced driver assistance systems (ADAS) make a decisive contribution to that. Although the computing power of modern ADAS is fast growing, a simplification of the algorithms used can further improve the reliability and effectiveness of such systems. The permanent calculation of the time to collision (TTC) with objects moving on a non defined motion path requires a high computing power. The paper will explain a new algorithm-based approach to make future ADAS faster with simultaneously increasing the reliability.
2015-04-14
Journal Article
2015-01-0152
Rafal Tomasz Dlugosz, Michał Szulc, Marta Kolasa, Pawel Skruch, Krzysztof Kogut, Paweł Markiewicz, Mateusz Orlowski, Maciej Różewicz, Anna Ryszka, Dominik Sasin, Tomasz Talaska
Abstract In this paper we present an example design process of filters used in automotive industry. Signal preprocessing is very important operation in active safety algorithms. Such algorithms usually take into account the vehicle state that includes position, velocities and accelerations of the car. On the basis of these data, as well as the parameters and trajectories of external objects “observed” by the car, the algorithms make decisions about various safety actions. Designer of such algorithms must assure an appropriate quality of such signals, which usually means a proper filtering. In this paper we focus on selected important aspects of the filter design process. The main objectives of the presented investigations is to obtain such filters that ensure a sufficient rejection of undesired components from the signal and at the same time that do not introduce too high delay to the processed signals.
2015-04-14
Journal Article
2015-01-0155
Sami H. Karaki, Rafika Dinnawi, Rabih Jabr, Riad Chedid, Ferdinand Panik
Abstract An optimal design methodology is developed in this paper for fuel cell hybrid electric vehicles (FCHEV) based on ordinal optimization (OO) and dynamic programming (DP); the optimal design aims to determine the appropriate sizes of the hydrogen tank, fuel cell, battery, and motor for the purpose of minimizing investment and operational cost given some specification of the car range, the road type and its gradeability. The DP simulates the operation of the vehicle for a set of specified components' sizes for given driving cycles and provides the total vehicle cost per year. The OO method offers an efficient approach for optimization by focusing on ranking and selecting a finite set of “good enough” alternatives through two models: a simple model and an accurate model. The OO program uses the specified sizes of the components that uniformly sample the search space and evaluates these designs using a simple but fast model.
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