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Since the 1990's regulatory requirements for On-BoardDiagnostics (OBD) have continuously evolved with an increasing application of advanced electronics and control systems that have been adopted for automotive applications. The current and future demands on emissions and performance requirements are pushing the envelope with respect to management of complex control software strategies, hardware components and their interactions. This further challenges the implementation of OBD. In order to build a robust monitor for a complex system which has minimum risk of false detection, a thorough understanding of both system and components is required. In this paper, several methods will be presented that can be utilized to achieve a successful and robust diagnostic system implementation. Implementation begins with a discussion of the major challenges to achieve consistent performance in the base system control. A deep dive approach will provide new methodologies that can be applied to address the necessary diagnostics. This paper will address diagnostic fault handling based on symptoms, statistical methodologies for filtering out noise, and implementation of reference models for diagnostics. It will also discuss redefining the goal of OBD implementation on modern control systems that have multiple I/O as well as coupled and decoupled configurations.

The turn signal is a vital safety feature that is not only required to be built in as standard equipment on all vehicles, but their use by the driver in everyday driving is required by law. Since not all drivers are diligent at properly actuating turn signals in every situation, the use of the turn signal is less than 100%. However, despite the fact that turn signals are a crash prevention feature, no known study relating to turn signal usage rates is available from the National Highway Traffic Safety Administration, nor from the Department of Transportation, nor from any University, nor from other private safety organizations. This paper summarizes a first-ever published comprehensive study related to turn signal usage rates by everyday drivers and summarizes it in a simple, yet highly accurate naturalistic observation format with the following basic premise: A vehicle is observed to be turning in a situation that is deemed by the observer to require a turn signal: was the turn signal “on” or was it “off” in that observed vehicle? The summary of the cumulated data of turn signal usage is expressed in terms of a percentage usage rate. All turning drivers are unaware that their visible actions are data points in a study so the results are extremely accurate. Both turns as well as lane change usage rates are studied. Crash rates resulting from neglected turn signals are discussed, revealing that this neglect causes more crashes than distracted driving. The present turn signal system that relies solely on driver input can only be described as “defective”. The paper also discusses how patented Electronic Intelligent Turn Signals with Turn Signal Assist would vastly improve usage rates and therefore significantly lower crash rates for no added vehicle cost.

For Homogeneous Charge Compression Ignition (HCCI) combustion, the auto-ignition process is very sensitive to in-cylinder conditions. This includes the change in in-cylinder temperature, the composition of chemical components and their concentrations. This sensitivity presents a major challenge for the accurate control of reliable and efficient HCCI combustion. This paper outlines our recent work: 1. a real-time control oriented gasoline-fueled HCCI combustion model and its implementation in Simulink with fixed step for the conversion into dSPACE Hardware-in-the-Loop (HIL) simulation purpose. 2. The development of model-based fast calibration for the best fuel efficiency and hydrocarbon emissions via evolutionary algorithm (EA). The model reported in this paper is able to run in real-time cycle-to-cycle under engine speeds below 4000rpm and with fixed simulation steps. This aims to achieve cycle-to-cycle performance calculation for Model based Predictive Control (MPC) and HIL simulation. With the aim of controlling the desired amount of trapped Exhaust Gas Recirculation (EGR) from the previous cycle, the phase of the Intake Valves Opening (IVO) and Exhaust Valves Closing (EVC) are designed to vary in this model. The model is able to anticipate the auto-ignition timing, MFB, combustion duration, in-cylinder pressure and hydrocarbon emissions etc. The validation has been conducted by comparing experimental data obtained from a Jaguar HCCI/SI V6 GDI engine at the University of Birmingham. This comparison shows good agreement between the simulation results and experimental data. Copyright © 2012 SAE International.

ISO 26262 is the first comprehensive automotive safety standard that addresses the safety of the growing number of electric/electronic and software intensive features in today's road vehicles. This paper assesses the standard's ability to provide safety assurance. The strengths of the standard are: (1) emphasizing safety management and safety culture; (2) prescribing a system engineering development process; (3) setting up a framework for hazard elimination early in the design process; (4) disassociating system safety risk assessment from component probabilistic failure rate. The third and fourth strengths are noteworthy departure from the philosophy of IEC61508. This standard has taken muchneeded and very positive steps towards ensuring the functional safety of the modern road vehicles. SAE publications from industry show a lot of enthusiasm towards this standard. This paper suggested a number of items to be considered further strengthen the standard's ability to provide safety assurance. First, the Automotive Safety Integrity Level (ASIL) assessment may want to consider only the severity level, so that the subjectivity involved in likelihood assessment is eliminated. The ASIL assessment also needs to be standardized across manufacturers in order to address the tension between safety and business competitiveness. Government, industry consortium, and research institutions may want to work together on ASIL standardization efforts. Second, this standard provides little guidance on how to eliminate hazards in the design, but rather provides details on how to design and evaluate the effectiveness of component failure detection and control mechanisms. This paper identifies research that could be conducted on how to adapt the System Theoretic Accident Modeling and Process model during the design phase. Third, this standard gives detailed guidance on reliability engineering methods for component failures, but little on system safety design methods. Reliability and safety are different attributes of the system. This standard can be improved by further research on adapting system safety engineering methods to this standard. Fourth, the standard also substitutes good software systems engineering practices for software safety, although this is on par with other industry standards. Further research is needed to address software safety assurance. Fifth, the need for more detail in the safety assurance process and plan for product and operation phases of the product are discussed. Last, the needs for better design methods and safety assurance plan concerning driver/vehicle interaction design are also presented.

This paper deals with the ground testing of the technological demonstrator of the innovativeremotely controlled ETF airship. The testing activities are intended to validate the flight control system of the ETF, which is based on the thrust vectoring technology and represents one of the major innovations of the ETF design, together with the airship architecture. A research team of the Aeronautical and Space Department of the Polytechnic of Turin, in collaboration with Nautilus, a small Italian private company, has been working since a few years on the ETF (Elettra Twin Flyers). This airship is remotely-piloted, with high maneuverability capabilities and good operative features also in adverse atmospheric conditions. The Nautilus new concept airship features architecture and appropriate command system, which should enable the vehicle to maneuver in forward, backward and sideward flight and hovering with any heading, both in normal and severe wind conditions. To achieve these capabilities the ETF demonstrator3 has been conceived with a highly non conventional architecture based on a double hull with a central plane housing structure, propellers, on board electric system and payload . As primary command system, the aerodynamic control surfaces are replaced by six propellers, which are moved by electrical motors and allow the airship to be controlled and maneuvered in the whole flight envelope. In this paper the results of the preliminary testing runs are analyzed and the power requirement is compared with the performance of the Fuel Cell system, purposely developed for the ETF Demonstrator.

The aerospace manufacturing sector is continuously seeking automation due to increased demand for the next generation single-isle aircraft. In order to reduce weight and fuel consumption aircraft manufacturers have increasingly started to use more composites as part of the structure. The manufacture and assembly of composites poses different constraints and challenges compared to the more traditional aircraft build consisting of metal components. In order to overcome these problems and to achieve the desired production rate existing manufacturing technologies have to be improved. New technologies and build concepts have to be developed in order to achieve the rate and ramp up of production and cost saving. This paper investigates how to achieve the rib hole key characteristic (KC) in a composite wing box assembly process. When the rib hole KC is out of tolerances, possibly, the KC can be achieved by imposing it by means of adjustable tooling and fixturing elements. A test rig has been designed and built that is used to experimentally investigate the capability of both the tooling and fixturing concepts. Some experiments have been carried out that successfully demonstrate the capability of the reconfigurable fixturing technology to achieve the rib hole KC.

Today CFD is an important tool for engineers in the automotive industry who model and simulate fluid flow. For the complex field of Under hood Thermal Management, CFD has become a very important tool to engineer the cooling airflow process in the engine bay of vehicles. To model the cooling airflow process accurately in CFD, it is of utmost importance to model all components in the cooling airflow path accurately. These components are the heat exchangers, fan and engine bay blockage effect. This paper presents CFD simulations together with correlating measurements of a cooling airflow system placed in a test rig. The system contains a heavy duty truck louvered fin radiator core, fan shroud, fan ring and fan. Behind the cooling module and fan a 1D engine silhouette is placed to mimic the blockage done by a truck engine behind the fan. Furthermore a simple hood is mounted over the module to mimic the air guiding done by the hood in an engine bay. The measurements monitor pressure and flow over the system. Supporting this examination is a set of 48 velocity probes in the radiator that measures the local velocity. The simulations of this system are correlated to measurements. Furthermore to support these simulations, specific simulations and measurements are conducted using the radiator only and the fan only. This is done to see how well each separate component is predicted in CFD and correlated back to measurements. This work is the continuation of work presented in [5] and identified in this paper is that one can simulate the cooling airflow system rather well with steady state CFD. However, fan modeling is sensitive and specific care has to be taken in order for these simulations to be accurate.

The introduction of advanced internal combustion engine mechanisms and powertrains may improve the fuel conversion efficiency of an engine and thus reduce the amount of energy needed to power the vehicle. The paper presents a novel design of a variable compression ratio advanced spark ignition engine that also permits an expansion ratio that may differ from the induction stroke therefore generating an Atkinson cycle effect. The stroke ratio and the ratio of maximum to minimum in-cylinder volumes may change with load and speed to provide the best fuel conversion efficiency. The variable ratio of maximum to minimum in-cylinder volumes also improves the full load power output of the engine. Results of vehicle driving cycle simulations of a light duty gasoline vehicle with the advanced engine show dramatic improvements of fuel economy. The novel gasoline vehicle has close to diesel fuel energy usage and CO2 production while retaining the after treatment advantages of the stoichiometric operation with spark ignition. Coupled to advanced powertrains using mechanical kinetic energy recovery systems to recover the braking energy thus reducing the thermal energy supply in the following acceleration phase, these engines may offer even better than current hybrid electric vehicles fuel economy (comparison of compact size passenger cars with a turbo direct injection diesel and a mechanical kinetic energy recovery system and a gasoline hybrid electric vehicle published in a previous paper). The results of the paper are based on modelling techniques. These results need to be confirmed by experiments.

The goal of this paper is to acquire insight into the influence of cetane number (CN) and fuel oxygen on overall engine performance in the Premixed Charge Compression Ignition (PCCI) combustion mode. From literature, it is known that low reactive (i.e. low CN) fuels increase the ignition delay (ID) and therefore the degree of mixing prior to auto-ignition. With respect to fuel oxygen, it is known that this has a favorable impact on soot emissions by means of carbon sequestration. This makes the use of low CN oxygen fuels an interesting route to improve the applicability of PCCI combustion in diesel engines. In earlier studies, performed on a heavy-duty engine, cyclic oxygenates were found to consistently outperform their straight and branched counterparts with respect to curbing soot. This was attributed to a considerably lower CN. The oxygenate in question, cyclohexanone (C6H10O), has the advantage of being producible in a renewable way from lignin, a second generation biomass waste stream (e.g. paper pulp industry). To investigate the impact of cyclohexanone on diesel combustion and pollutant emissions in greater detail, a parametric test program was carried out in a joint project between Istituto Motori (Naples) and the University of Technology Eindhoven. To decouple the influence of a low cetane number and fuel oxygen content on the engine performance, diesel (commercial high quality diesel fuel), gasoline (commercial high quality gasoline) and cyclohexanone were blended into five mixtures, with varying cetane number or oxygen content. These blends were tested and compared on a modern singlecylinder light-duty (LD) direct injection (DI) research diesel engine. The results suggest that it is not possible to attribute favorable performance to either CN or fuel oxygen, but rather to the combination of both properties. In nearly all investigated work points, a decrease in CN led to a decrease in nitric oxides (NOx) and particulate matter (PM), whilst slightly increasing carbon monoxide (CO) and unburned hydrocarbons (UHC). At an equal CN, the results suggest that fuel oxygen reduces soot emissions and also plays a role in suppressing UHC and CO emissions.

Characterization of combustion parameters of gaseous fuels is the main objective of a novel experimental laboratory, which recently became operational at Istituto Motori: the "Device for Hydrogen-Air Reaction Mode Analysis" (DHARMA in brief) project is meant to generate a systematic database on the burning properties of CH4, H2 and other species of interest, in conditions typical of i.c. engines. The experimental setup is based upon an optically accessible cylindrical bomb, where test are carried out on spherical expanding flames. High-speed shadowgraph is used to record the flame growth and to infer laminar burning parameters. Thorough details are given of the experimental apparatus and the data analysis. Experimental data are presented for the combustion in air of CH4 and of CH4/H2 mixtures: the percentage of hydrogen was 20% and 30% (vol.). The tests have been performed under the same conditions: equivalence ratio was 1.0, initial pressure and temperature were 6.0 bar and 293 K, respectively. Data analysis yielded the laminar burning velocity and Markstein length: the variation of these parameters has been evidenced as a function of the hydrogen content. The obtained results have been compared to those available in literature, showing a good agreement.

This paper proposes wall function models to simulate the heat transfer around a cylinder in cross flow with an isothermal and rough surface. The selected case has similitudes with aircraft wing icing: the ice roughness shape, height and distribution. Moreover, the flow is somewhat similar to that found on iced airfoil; and the surface is isothermal like when icing. The Reynolds-Averaged NavierStokes, turbulence, energy and mass conservation 7-equation system is solved by two Computational Fluid Dynamics (CFD) codes. To represent accurately the effects of roughness on the heat transfer, the present authors had to modify both codes and to propose new thermal wall functions for them. In addition, it was implemented a momentum wall function that is not so common in CFD codes but it is a standard in aircraft icing simulation. Basically, the present paper is focused on presenting the simulation results improvement obtained by the implementation of thermal wall functions that also considered the effect thermal resistance of viscous sub-layer on convective heat transfer. The numerical results were compared to experimental data of heat transfer around cylinders with an isothermally heated surface and equivalent sand grain roughness height of Ks=D = 900 10 5 . For the selected case, the flow regime was trans-critical at Reynolds numbers Re = ue D=n = 2:2 10 5 . Due to significant blockage effects present in the experimental data, the tunnel walls were also meshed and simulated. In sum, the implementation into CFD codes was considered adequate because the results were close to experimental data around the whole cylinder surface, not only along the leading edge or the separated region. The results accuracy were improved when compared with CFD factory original models. However, the results indicate that further works on wall functions and their validation are required before using CFD in wing aircraft icing.

During the past two decades the occurrence of ice accretionwithin commercial high bypass aircraft turbine engines undercertain operating conditions has been reported. Numerousengine anomalies have taken place at high altitudes that wereattributed to ice crystal ingestion such as degraded engineperformance, engine roll back, compressor surge and stall,and even flameout of the combustor. As ice crystals areingested into the engine and low pressure compressionsystem, the air temperature increases and a portion of the icemelts allowing the ice-water mixture to stick to the metalsurfaces of the engine core. The focus of this paper is onestimating the effects of ice accretion on the low pressurecompressor, and quantifying its effects on the engine systemthroughout a notional flight trajectory. In this paper it wasnecessary to initially assume a temperature range in whichengine icing would occur. This provided a mechanism tolocate potential component icing sites and allow thecomputational tools to add blockages due to ice accretion in aparametric fashion. Ultimately the location and level ofblockage due to icing would be provided by an ice accretioncode. To proceed, an engine system modeling code and amean line compressor flow analysis code were utilized tocalculate the flow conditions in the fan-core and low pressurecompressor and to identify potential locations within thecompressor where ice may accrete. Note that there is abaseline value of aerodynamic blockage due to low velocityair near the compressor inner and outer walls and bladesurfaces (boundary layer blockage). There is also a blockagedue to the blade metal thickness. In this study, the “additionalblockage” refers to blockage due to the accretion of ice on themetal surfaces. Once the potential locations of ice accretionare identified, the levels of additional blockage due toaccretion were parametrically varied to estimate the effectson the low pressure compressor blade row performanceoperating within the engine system environment. This studyincludes detailed analysis of compressor and engineperformance during cruise and descent operating conditionsat several altitudes within the notional flight trajectory. Thepurpose of this effort is to develop the codes to provide apredictive capability to forecast the onset of engine icingevents, such that they could help in the avoidance of theseevents.It has been reported that ice crystal accretion in gas turbineengines is dependent on the amount of mixed phaseconditions (liquid and solid) that exist. In addition, theproblem of ice accretion is highly multi-disciplinary, since itinvolves heat transfer from the air to the compressor metalsurfaces. The first phase of this study focuses on addressingthe thermodynamic cycle through the engine system code andthe mean line flow analysis through the compressor through aflight trajectory. The second phase of this study focuses on

Ice buildup in the compressor section of a commercial aircraft gas turbine engine can cause a number of engine failures. One of these failure modes is known as engine rollback: an uncommanded decrease in thrust accompanied by a decrease in fan speed and an increase in turbine temperature. This paper describes the development of a model which simulates the system level impact of engine icing using the Commercial Modular Aero-Propulsion System Simulation 40k (C-MAPSS40k). When an ice blockage is added to C-MAPSS40k, the control system responds in a manner similar to that of an actual engine, and, in cases with severe blockage, an engine rollback is observed. Using this capability to simulate engine rollback, a proof-of-concept detection scheme is developed and tested using only typical engine sensors. This paper concludes that the engine control system s limit protection is the proximate cause of iced engine rollback and that the controller can detect the buildup of ice particles in the compressor section. This work serves as a feasibility study for continued research into the detection and mitigation of engine rollback using the propulsion control system.

All surfaces of a cabin interior may contribute to the sound pressure at a certain reference position, e.g. the human's ear. Panel noise contribution analysis (PNCA) involves the measurement of the contribution of separate areas. This is an effective method to determine the effect of apparent noise sources at a specific location. This paper presents the latest developments on particle velocity based panel noise contribution analysis. In contrast to the traditional methods, the particle velocity approach is faster; it requires 3 days instead of weeks. While the theoretical base of the procedure in this paper is similar to previously published particle velocity based procedure, here the measurement protocol has now been simplified dramatically, which has reduced the measurement time even more to less than a day. The method and its implementation are explained in the paper and a full measurement procedure is reported. Four steps are required to determine and visualize the pressure contribution of the vehicle interior. In a first step, probes are positioned on predefined interior surfaces. Special probe mounting have been made to decrease the handling time. The second step is a measurement in a certain mode of operation. This step can be done in a laboratory but it is also possible to perform the measurement whilst driving the vehicle on the road. Stationary as well as non stationary running conditions like run ups are accessible and do not limit the applicability of the method. The third step is the determination of the transfer paths from the panels to a certain listening position. This measurement is done assuming reciprocity. A monopole source is placed on the listener position and the sound pressure is measured at the surface. In a fourth and last step the transfer paths are linked with the operational data gathered in step two. The results are then visualized using the predefined geometry model. This paper describes the measurement of a conventional car with a resolution of 137 panels. Since an array of 46 probes was used step 2 and step 3 are repeated 3 times.

The use of oxygenated and renewable fuels is nowadays a widespread means to reduce regulated pollutant emissions produced by internal combustion engines, as well as to reduce the greenhouse impact of transportation. Besides PM, NOx and HC emissions, also the size distribution of particles emitted at the engine exhaust represent a meaningful information, considering its adverse effects on the environment and human health. In this work, the results of a comprehensive investigation on the combustion characteristics and the exhaust emissions of a GDI high performance engine, fuelled with pure Bio-ethanol and European gasoline, are shown. The engine is a 4-cylinder, 4 stroke, 1750 cm3 displacement, and turbocharged. The engine was operated at different speed/load conditions and two fuel injection strategies were investigated: homogeneous charge mode and stratified charge mode. The particle size distribution at the engine exhaust was measured in the range 5-1000 nm using a differential mobility spectrometer. Simultaneously, the air-fuel mixing and the combustion process inside the cylinder were followed by means of high-speed imaging in the UV-visible. To this aim, the last cylinder was optically accessible through a sapphire window (5mm wide) in the engine head. The particles size distributions measured at the engine exhaust for both gasoline and bio-ethanol show similar trends, suggesting a common route for the particles formation. For bio-ethanol the accumulation mode is shifted towards smaller sizes, which could be ascribed to the chemical and physical properties of the fuel, as observed by optical investigation of the fuel injection and combustion process. On the other hand, an increase of particles number concentration for stratified charge operating mode was observed for both fuels, due to the poorer air fuel mixing and the diffusive combustion of the fuel films deposited on the piston and cylinder wall.

Parabolic leaf spring plays a vital role in the suspension systems, since it has an effect on ride comfort and vehicle dynamics. Primarily, leaf spring endurance must be ensured. Presently, there are two approaches to design a leaf spring. In traditional method, fatigue tests should be repeated for each case considering different material, geometry and suspension hard points. However, it takes a long time and requires heavy budget to get the optimized solution. In the recent method, numerical approach is used to obtain the fatigue life and the leaf geometry against the environmental condition on the base of material properties. This paper presents a more precise method based on non-linear finite element solutions by evaluating the effects of the production parameters, the geometrical tolerances and the variations in the characteristics of the material. In other words, it is a hybrid method, between the traditional and the recent ones, which correlates the real life conditions and the results of computer aided engineering. The leaf springs in different characteristics have been produced and tested in the plant of OlgunCelik plant. The design methodology of this paper brings also a practical approach to the professionals in the industry. It aims to create a design tool with 2D FEA which is well correlated with 3D.The correlation of 3D and simple 2D methods with experiments are validated through a design of experiment (DOE) study. INTRODUCTION Parabolic leaf springs are the components of the suspension system. They perform isolation task in transferring vibration due to road conditions to body. There are various versions of the parabolic leaf springs such as parabolic, multi-parabolic and z-leaf spring. Development of a leaf spring is a long process which requires lots of test to validate the design and manufacturing variables. We have used CAE to shorten this development cycle by implying CAE as much as possible to reduce the tests. A systematic procedure is obtained where CAE and tests are used together. LEAF SPRING HYBRID DESIGN METHODOLOGY Every design method having CAE in the process must be based on validated virtual models. We have validated our finite element analysis models by experimental studies. These studies were carried out by the controlled manufacturing processes, measured manufacturing variables and comparison of the test results and virtual model using real variables. Primary output obtained from both test or finite element analysis of leaf springs are spring rate (force, displacement) and fatigue strength. In order to understand the parameters affecting fatigue strength of the leaf spring we have carried out a series of experiments in varying conditions. We have determined 26 parameters affecting fatigue results (Table1) depending on our experience and leaf spring boundary diagram (Table 2). Some of the parameters are major and other are minor. Design process starts with conceptual phase w general dimensions and shape of the leaf spring are determined. Conceptual phase decisions are based on experience and in-house software. Then a finite element model with nominal parameters is created. Design is optimized initially with nominal parameters. to reach required force-displacement curve, hence spring rate and stress level which is one of the important factors defining the fatigue strength. Then factors affecting fatigue are selected from the list given in Table 1 depending on project type, known tolerances, supplier data etc. The effect of these variables are studied in CAE by means of 3D and 2D models. This step is known as Design of Experiment (DOE). As a result of this DOE study, not only the CAD models but also decisions that are taken given in Table 1 are optimized. Prototypes are after having been produced. Figure 1. Hybrid Design Process

In this paper a state space representation of a turbocharged diesel engine is provided based on off-line least square method. Internal combustion engines show high nonlinear behavior due to complicated combustion phenomena and air flow dynamics inside the engine. In development phase of modern control methods like LQR controller, an accurate state space model with meaningful and measurable states is required. Identification is the method of deriving a mathematical model for dynamic systems based on inputoutput data. In this paper a mean value model of a turbocharged diesel engine is employed to generate demanded input-output data for identification purposes. This nonlinear mean value model predicts engine speed as a function mass of fuel injected per cycle, injection timing (ξ), ambient pressure and temperature and external loads. In the next step the simulation data is used to develop a state space model around idle mode operation state. Least square method is then employed to identify a linear time invariant state space model out of input-output data. In doing so, band limited white noise is used to generate demanded I/O data for model identification purposes. In the next step subsequent results are used to identify the LTI model based on LS. Load is considered as a disturbance while mass of injected fuel and injection timing is two main inputs of the model. Engine speed is considered the only output. Inlet and exhaust manifolds pressure, turbocharger speed and engine speed are 4 states of engine. Comparison between the nonlinear model results and state space model data show acceptable similarity. The results show that this scheme can be used for online identification of engine in fault detection and adaptive control processes.

Over the past couple of years, numerous Hybrid Electric Vehicle (HEV) powertrain configurations have been introduced into the marketplace. Currently, the dominant architecture is the power-split configuration, notably the input splits from Toyota Motor Sales and Ford Motor Company. This paper compares two vehicle-level control strategies that have been developed to minimize fuel consumption while maintaining acceptable performance and drive quality. The first control is rules based and was developed on the basis of test data from the Toyota Prius as provided by Argonne National Laboratory’s (Argonne’s) Advanced Powertrain Research Facility. The second control is based on an instantaneous optimization developed to minimize the system losses at every sample time. This paper describes the algorithms of each control and compares vehicle fuel economy (FE) on several drive cycles. Results demonstrate that both algorithms achieve similar FE values, which serve to demonstrate the benefits of the instantaneous optimal control: because it does not require tuning by the engineers, control development time is accelerated.

Helsinki Region Transport, Neste Oil, Proventia Emission Control and VTT Technical Research Centre of Finland carried out a 3.5 year PPP venture "OPTIBIO" to demonstrate the use of paraffinic renewable diesel (hydrotreated vegetable oil HVO) in city buses. The fleet test in Metropolitan Helsinki involving some 300 buses is the largest one in the world to demonstrate this new fuel. The fuels were a 30 % blend of renewable diesel and 100 % renewable diesel. This paper describes the overall set-up of the project, gives an overview of the emission results as well as presents experience from the field.

This paper describes how an ideal injury criterion should be predictive of the risk of injury across the range of loading conditions where it may be applied. The injury risk curve associated with this criterion should be applicable to all loading conditions. With respect to side impact, the injury risk curve should apply to pure lateral or oblique loading by rigid and padded walls, as well as airbags. Previous research reported that the number of fractured ribs was higher in pure lateral impact than in forward oblique interaction with an airbag. The paper describes how a good dummy criterion should be able to account for this difference. In order to evaluate various injury criteria with the WorldSID 50th and ES-2re dummies, the dummies were exposed to the same airbag loadings as the post-mortem highway surrogates (PMHS) and the criteria measured in the dummy tests were paired with the rib fractures from the PMHS tests. Regarding the effect of configuration, results of sled tests with the 50th percentile WorldSID and ES-2re have been paired with injuries found in the PMHS tested in the same conditions. The relationships obtained were compared with the relationships established in the same way for the subjects loaded in the airbag tests. Comparing the lateral and oblique lateral loading conditions, both the WorldSID and the ES-2re exhibited differences in peak lateral deflection of their ribs that were consistent with the different number of rib fractures for PMHS subjected to these loading conditions. For each dummy, the risk of rib fractures could be assessed from one injury risk curve, regardless of the loading angle and the same injury risk curve can be used to assess the risk of rib fractures from sled tests and airbag loading. However, because the WorldSID deflection measurements differed in the rigid and padded sled tests, it is recommended that the dummy's sensitivity to padding be further assessed prior to adopting injury risk curves for WorldSID. Rib deflections of the ES- 2re were not sensitive to padding. Finally, the paper shows how the VC should not be considered as a valid criterion to assess the risk of rib fractures.

This paper describes how the increasing number of people over 65 years old is an important research topic in the area of impact biomechanics. The paper shows how finite element (FE) modeling can provide valuable support for related research. There were three objectives for this paper: (1) estimation of the representative age of the previously-documented Ford Human Body Model (FHBM) -- a FE model that approximates the geometry and mass of a mid-sized male; (2) development of FE models representing two additional ages; and (3) validation of the resulting three models to the extent possible with respect to available physical tests. Specifically, the geometry of the model was compared to published data relating rib angles to age, and the mechanical properties of different simulated tissues were compared to a number of published aging functions. The FHBM was determined to represent a range of 53 to 59 year old mid-sized males. The aforementioned aging functions were used to develop FE models representing two additional ages: 35 and 75 year old. The rib model was validated against human rib specimens and whole rib tests, under different loading conditions, with and without modeled fracture. In addition, the resulting three age-dependent models were validated by simulating cadaveric tests of blunt and sled impacts. The responses of the models, in general, were within the cadaveric response corridors. When compared to peak responses from individual cadavers similar in size and age to the age-dependent models, some responses were within one standard deviation of the test data. All the other responses, but one, were within two standard deviations.

Model-based software development is increasingly being used to develop software for electronic control units (ECUs). When developing safety-related software, compared to nonsafety-related software development, additional requirements specified by relevant safety-standards have to be met. Meeting these requirements should also be considered to be best practices for non-safety-related software. This paper introduces a model-based reference workflow for the development of safety-related software conforming to relevant safety-standards such as IEC 61508 and ISO 26262. The reference workflow discusses requirements traceability aspects, software architecture considerations that help to support modular development and ease the verification of model parts and the code generated from those model parts, and the selection and enforcement of modeling and coding guidelines. Special focus is put on software unit and integration testing as an integral part of the overall verification and validation task. The presented methods and measures are mapped to the requirements of relevant functional safety-standards applied in the automotive industry. Furthermore the paper discusses the role of such a reference workflow for answering the ongoing question for software tool qualification. The new automotive safety-standard ISO 26262 introduces a new approach to adressing this topic. This approach is based on a new way of classifcation of the software tool based on the tools impact and the degree of confidence that a malfunction or erroneous output can be prevented or detected. SAFETY STANDARDS Standards that apply to automotive software development are IEC 61508 [1] and particularly new ISO 26262 [2]. IEC 61508 is a generic across-the-industries standard that encourages the derivation of industry-specific standards. It originated in the process control automation industry, and sector-specific standards have already been derived for the process industry (IEC 61511), nuclear power plants (IEC 61513) and machinery (IEC 61513). New ISO 26262, which reached ISO Draft International Standard (DIS) status in July 2009, is a derivative that is especially tailored to the automotive industry. Where IEC 61508 has to remain abstract in many points, ISO 26262 is far more specific with regard to automotive electronics development. IEC 61508 was created and published in the late 1990s, before model-based development and code generation became widely adopted. It can therefore give little direct advice of how to comply within a model-based development process. The standard has therefore to be interpreted. ISO 26262 AND MODEL-BASED DEVELOPMENT ISO 26262 addresses this issue and specifically covers model-based development aspects, reflecting the importance of this approach in automotive software development today. The ISO 26262 part relevant to model-based development is “Part 6: Product development: software level”. It contains a separate chapter in the annex that describes the concept of model-based development of in-vehicle software and outlines its implications on the product development at the software level. In this annex also differences between code-based and model-based development are pointed out. Furthermore there are several notes throughout ISO/DIS 26262-6 directly A Model-Based Reference Workflow for the Development of Safety-Related Software 2010-01-2338 Published 10/19/2010

A new design of integrated Electric Parking Brake system, called iEPB and integrated in the brake caliper, is introduced in this paper. It consists of an electrically operated brake unit and a hydraulically pressed unit independently, and uses a special self-locking mechanism instead of a screw device to increase the efficiency and the working speed. With all conventional EPB system’s advantages, it also provides a stronger brake performance and a faster reaction time. In this paper, we describe the working principle of this new design at first, and then introduce the arrangement of the testing system, followed by a discussion of experimental data. The testing results prove the feasibility of this design. The conclusion paragraph summarizes the key points about the design of the iEPB system. INTRODUCTION The iEPB system is more convenient and safety than traditional parking systems. It’s operated and released automatically. With integrated intelligent function, the iEPB system has the following merits: • Replace a hand lever by an operation button. • Because of no hand lever, there is more space in the vehicle. • Combining a control unit, the iEPB system can be automatically operated and released at the right time, which makes the operation simpler and the driver to feel more comfortable and safer. • With high performance mechanism, the iEPB system has a faster reaction time. So we can provide the Auto-Hold function by adopting the iEPB system. There are two types of existing electric parking brake. One type is the cable puller[3], and the other is the integrated caliper[4]. This new design belongs to the integrated caliper type. Almost 100% integrated caliper type of market products use the screw device as its linear mechanism. The screw device can provide a large reduction ratio in a small space and transfer the rotation motion into linear motion with a non-reverse feature. But a low mechanical efficiency due to the screw friction makes a great energy lose. In this paper, we introduce a new design that is a type of screw free concept. Basing on the same power source, the screw free design can reduce about three-quarter reaction time of the system [5]. SYSTEM DESCRIPTION For improving working speed, enhancing mechanism efficiency and providing a non-reverse feature at the same time, the iEPB mechanism design is the key point. The important factors that need to be considered include: • Caliper pressing force. • Working time of the actuator. • Power consumption. • Parking force that can be maintained when power off. Actuator parts The iEPB system working flow diagram is shown in Figure 1, and the illustration of actuator is shown in Figure 2. The iEPB system is comprised of a brush DC motor, a special self-locking mechanism and multi stage reduction gears. The output torque rotates a cam shaft built in the caliper and pushes brake lining to against brake disk for parking purpose, shown in Figure 3. There is no additional friction lose because of the screw free mechanism. The prototype picture is shown in figure 4. Motor Self-locking mechanism Reduction gear Caliper cam shaft Cam Lining shoe Parking Figure 1. iEPB system working flow diagram. Reduction Gear Self-locking mechanism

This paper presents the business purpose, software architecture, technology integration, and applications of the Cummins Vehicle Mission Simulation (VMS) software. VMS is the value-based analysis tool used by the marketing, sales, and product engineering functions to simulate vehicle missions quickly and to gauge, communicate, and improve the value proposition of Cummins engines to customers. VMS leverages the best of software architecture practices and proven technologies available today. It consists of a close integration of MATLAB and Simulink with Java, XML, and JDBC technologies. This Windows compatible application software uses stand-alone mathematical models compiled using Real Time Workshop. A built-in MySQL database contains product data for engines, driveline components, vehicles, and topographic routes. This paper outlines the database governance model that facilitates effective management, control, and distribution of engine and vehicle data across the enterprise. This paper also presents four case studies on the applications of VMS to augment Cummins engineering and sales competencies by helping customers understand vehicle performance, optimize vehicle configurations, improve fuel economy, and reduce greenhouse gas emissions. INTRODUCTION The commercial vehicle industry has become increasingly aware of the interconnectedness of the components of a vehicle. Companies now research and engineer products around how each component interacts with other elements of the vehicle. Commercial software tools such as AVL Cruise, AVL ISAC, Advisor, GTDrive, and PSAT have evolved to support holistic vehicle integration, evaluate energy efficiency, and analyze componentlevel and system-level performance. To supplement the above commercial software tools, engine and vehicle manufacturers have also developed inhouse performance modeling software customized around their operating needs. Cummins uses an array of engine and vehicle validation tools as illustrated in Figure 1. Our suite of simulation tools, collectively called “CyberApps”, has been developed and validated over a span of 14 years. It operates a Unix based modeling platform and offers increasing degrees of fidelity by substituting mathematical models with hardware-in-loop Page 2 of 16 units of engine and vehicle subsystems. The simplest of these tools, “PureSim”, operates exclusively on MATLAB and Simulink models. It is this version of CyberApps that we have ported to Windows and adapted as the mathematical backbone of the analysis software that we describe in this paper. A discussion of the CyberApps mathematical models and validation process is outside the scope of this paper. Figure 1: Vehicle and engine testing and simulation tools used at Cummins Figure 2: Segmentation of users of engine-vehicle integration analysis software The in-house and commercial analysis tools we discussed above cater principally to the needs of advanced product engineering and research groups as illustrated in Figure 2. Consequently, these tools are complex, difficult to access, time-consuming and expensive for users outside of the engineering functions. These tools En gi ne C on tro l

Building prototype aircrafts is costly in tooling especially since only one aircraft is being built. Today's most common tooling strategy is to weld together a beam framework. Welded framework solutions have long lead times both in design and manufacturing and once the aircraft is assembled the tool becomes obsolete. Flexible tooling strategy uses non-welded tooling thus it can be changed and re-used for future products. Early version of a new aircraft model is always hampered by frequent changes in its design, which is cumbersome to handle in a welded framework solution. This paper presents a flexible assembly tooling solutions based on Flexapods and BoxJoint. The Flexapods are commercialized reconfigurable tooling units that are manually adjusted injunction with a laser tracker to a final positional accuracy of +/? 0,05 mm absolute accuracy. An operator software program called the Flexapod control panel collect metrology data in real-time and an operator screen show graphics on how to manually jog the Flexapod joints to reach the final Cartesian 3D-coordinate. The Flexapods are installed in a modular steel based framework solution called BoxJoint. A complete PLM package has been developed for the solution where the Flexapods are configured in CATIA using an add-on package to CATIA called the Flexapod configurator. All CATIA data is stored in ENOVIA. Once the Flexapod fixture is designed in CATIA a file, containing all Cartesian coordinates of the Flexapods, is exported and loaded into the Flexapod control panel on the workshop floor. A previous paper on the Flexapod as an early concept and a paper on BoxJoint have been presented at SAE Aerofast. This paper follows up on these results and presents a case study at SAAB Aeronautics for implementing the first industrial solution of Flexapods to build the military unmanned aerial vehicle - nEURON.

Copyright © 2009 SAE Japan and Copyright © 2009 SAE International – 2009 SETC. This paper is posted on this site with permission. As a user of this site, you are permitted to view this paper on-line, and print one copy of this paper at no cost for your use only. This paper may not be copied, distributed or forwarded to others for any use without permission from the copyright holder.

This paper will present the latest development of a configurable and modular steel construction system for use in frameworks of flexible fixtures of the kind called Affordable Reconfigurable Fixtures (ART). Instead of a dedicated aircraft fixture, which is very time consuming and expensive, the ART fixtures enable affordable construction from a standard component kit, by solving the main draw-backs of traditional tooling. In early 2009 Airbus UK built the first steel modular fixture for the aerospace industry. The project was a partnership with DELFOi and Linkoping University in a project called ReFlex, Reconfigurable Flexible Tooling. A paper was presented in the last year SAE conference which explained about the project in overall. The construction system called BoxJoint has recently been tested in some manufacturing areas at Airbus UK and also been applied in the production at Saab Aerospace Linkoping Sweden. A case study was conducted of an A380 subassembly fixture demonstrating the comparable advantages of the new technology from the design phase until the first aircraft build. One of the benefits reported is that a modular fixture relatively quickly can be assembled and set within specified tolerances by means of a metrology system, guiding configurable pickups and flags called Flexapods. Calculation of strength and stiffness can be made by simple standard methods.

The air-cooled engine surfaces are generally provided with extended surfaces of high conducting materials called fins for enhanced heat transfer. One way to increase the rate of heat transfer is by increasing the fins surface area. However, increase in fin length introduces undesirable vibrations of the fins, which in turn radiate annoying high frequency noise. With the demand of quieter engines increasing, the vehicle manufacturers follow counter measures to minimize the fin vibrations. One trend in the two-wheeler industry is to put rubber dampers between the fins. These rubber dampers damps out the level of vibrations and the level of noise radiated is reduced. However, these rubber dampers have many disadvantages. Apart from the adding extra cost and a parallel manufacture process, these rubbers act as an insulating material, which impede the free flow of cooling air. The engine may get overheated and purpose of providing extended surface would not be satisfied. In this paper, effect of these rubber dampers on engine radiated noise and thermal performance is investigated. We discuss a systematic methodology on how to remove these rubbers by keeping the noise level same along with higher heat transfer from the engine surfaces. Results from experiments and numerical simulations for noise & vibration and computation fluid dynamics (CFD) with conjugate heat transfer are discussed. This paper describes a classic example of multi-disciplinary approach to solve real-world design problems.

As it is well known one of the most harmful emissions in SI engines is NOx and there are several ways to minimize NOx emission. Internal exhaust gas recirculation (IGR) is an effective way to control and minimize NOx concentration in exhaust gas. In this paper, a method for minimizing NOx emission by use of IGR and variable valve timing (VVT) is introduced. In this method, formation of NOx is controlled by mass fraction of residual gas (RG) and mass fraction of RG is controlled by variable timing of exhaust valves opening and closing so not only the timing of exhaust valves changes but also the lift profile of exhaust valves is variable. In this paper, first a thermodynamic model of a SI engine was developed and validated by experimental data. The model was a reliable tool for predicting engine performance and emission characteristics. The effect of variable exhaust valve timing on RG mass fraction, NOx formation and brake specific fuel consumption was investigated. Then a multi-objective genetic algorithm (NSGA II) was applied to find the optimum timing and lift duration of exhaust valve.

The increasing use of distributed functions in vehicles can introduce unexpected and undesirable emergent behavior. This can be as a result of transient events such as sudden drops in the supply voltage. In this situation system behavior is often not adequately specified or controlled. This paper presents a novel approach to automotive electronic systems testing addressing robustness against low voltage transient conditions. The paper will discuss the technical output as well as performance in real-world test usage. The proposed approach uses a combination of pseudo-random number generator algorithms to generate parameterized supply voltage waveforms simulating low voltage transient conditions, used to drive the system-under-test (SUT). Two measures are used to judge whether the SUT has passed or failed the test; the detection of unintended recorded Diagnostic Trouble Codes (DTCs) from the error memory of each Electronic Control Unit (ECU) and the detection of unexpected system functionality by a human observer or automated vision system.

SAE paper 2010-01-0605, Copyright © 2010 SAE International. This paper is posted on this site with permission from SAE International, and is for viewing only. Further use and distribution of this paper is not permitted without permission from SAE. Over the last decade, the diesel engine has made dramatic progress in its performance and market penetration. However, in order to meet future emissions legislations, Nitrogen Oxides (NOx) and particulate matters’ (PM) emissions will need to be reduced simultaneously. Nowadays researchers are focused on different combustion modes which can have a great potential for both low soot and low NOx. In order to achieve this, different injection strategies have been investigated. This study investigates the effects of split injection strategies with high levels of Exhaust Gas Recirculation (EGR) on combustion performance and emissions in a single cylinder direct injection optical diesel engine. The investigation is focused on the effects of injection timing of split injection strategies. A Ricardo Hydra single cylinder optical engine was used in which conventional experimental methods like cylinder pressure data, heat release analysis and exhaust emissions analysis were applied. Optical techniques like direct spray and combustion visualization were applied by means of a high speed imaging system with a copper vapor laser illumination system and a high-speed two-color system was applied to obtain in-cylinder diesel combustion temperature and soot measurements distributions.

This paper presents the design and development of a prototype Head-Up Display (HUD) interface that offer early notification warnings of potential collisions under unfavourable weather and traffic conditions. In this work we particularly focus our effort in the embedment of traffic congestion and sharp turn visual warnings in a working prototype interface. In turn we present the results of a large scale evaluation of the system on a group of forty users, which contrasted the use of the proposed HUD against a typical HDD. Finally the paper offers suggestions for further research and a tentative plan for future work.

A multimode transmission combines several power-split modes and possibly several fixed gear modes, thanks to complex arrangements of planetary gearsets, clutches and electric motors. Coupled to a battery, it can be used in a highly flexible hybrid configuration, which is especially practical for larger cars. The Chevrolet Tahoe Hybrid is the first light-duty vehicle featuring such a system. This paper introduces the use of a high-level vehicle controller based on instantaneous optimization to select the most appropriate mode for minimizing fuel consumption under a broad range of vehicle operating conditions. The control uses partial optimization: the engine ON/OFF and the battery power demand regulating the battery state-of-charge are decided by a rulebased logic; the transmission mode as well as the operating points are chosen by an instantaneous optimization module that aims at minimizing the fuel consumption at each time step. The controller is then implemented in a Simulink/Stateflow controller that can be used in Argonne's PSAT (Powertrain System Analysis Toolkit), a forward-looking powertrain simulation toolkit with dynamic plant models. As a result, the controller described in this paper is realistically implementable on an actual vehicle. Simulation results show the mode use and describe the practical operations of the system.

In this paper a numerical model is used for analysis of parameters, which affects heat pipe operation. The steady state incompressible flow are solved in Cartesian coordinates in both vapour region and wick structure, using professional CFD (Computational Fluid Dynamics) software. The objectives of this paper were to study of the parameters variation on the operation of heat pipes. The heat pipes are made from copper tube with the outer diameter 8.9 [mm] and the length 200 [mm]. The water is used as a base working fluid while the nanoparticles used in the present study are the iron oxide nanoparticles. Two cases with volume concentration 0 and 2% for iron oxide nanoparticles are considered. Fig.1. Heat pipe construction and principle of operation. In this paper, using the facilities offered by the ANSYS CFX, CFD code, the authors investigate numerically the analysis of parameters which affects heat pipe operation. The steady state incompressible flow is solved in Cartesian coordinates in both vapour region and porous media. The objective of this paper was to study of the parameters variation on the operation of the heat pipes. The heat pipes are made from copper tube with the outer diameter 8.9 [mm] and the length 200 [mm]. The water is used as a base working fluid while the nanoparticles used in the present study are the iron oxide nanoparticles. Two cases with volume concentration 0 and 2% for iron oxide nanoparticles are considered. The geometry creation, which consists of annular concentric heat pipe, through which circulates water and water vapour, were drawn as a CAD data, with the aid of a professional software – package, ACAD 2002, and imported in ANSYS Workbench environment as SAT file.

With the growing complexity of, and reliance on, safety-related electrical/electronic (E/E) systems in the automotive sector, the development of an explicit safety case is highly recommended to provide assurance to the different stakeholders interested in automotive functional safety. The production of a safety case is explicitly mandated by the draft automotive functional safety standard ISO26262. A safety case should consider all organisational and technical factors that may contribute to safety. For example, it should provide assurance for the safe behaviours of a particular system as well as assurance for the process by which this system is developed, operated and maintained. In this paper, we address one component of the overall safety case, namely the assurance of the functional safety concept. In particular, we examine how model-driven development and assessment can provide a basis for the systematic generation of functional safety requirements. We demonstrate how an automotive safety case can be structurally and traceably developed, justifying why and how the defined functional safety requirements can adequately mitigate the risk of the identified hazards to an acceptable level. A case study is also presented throughout this paper, discussing examples and lessons learnt from the development of a safety case for an air suspension system.

SAE paper 2010-01-0843: Copyright © 2010 SAE International. This paper is posted on this site with permission from SAE International, and is for viewing only. Further use and distribution of this paper is not permitted without permission from SAE. Due to its potential for simultaneous improvement in fuel consumption and exhaust emissions, controlled autoignition (CAI) combustion has been subject to continuous research in the last several years. At the same time, there has been a lot of interest in the use of alternative fuels in order to reduce reliance on conventional fossil fuels. Therefore, this experimental study has been carried out to investigate the effect of alcohol fuels on the CAI combustion process and on the resulting engine performance. The experimental work was conducted on an optical single cylinder engine with an air-assisted injector. To achieve controlled autoignition, residual gas was trapped in the cylinder by using negative valve overlap and an intake air heater was used to ensure stable CAI combustion in the optical engine. Methanol, ethanol and blended fuels were tested and compared with the results of gasoline. The combustion processes were analysed through total chemiluminescence images captured with a high speed camera equipped with an intensifier. In addition, the effect of spark discharge was investigated. The images show that CAI combustion of alcohol fuels was characterized with fast and early autoignition combustion compared with pure gasoline. Chemiluminescence of the gasoline fuel was most visible and it decreased with increasing percentage of oxygenated fuels. During the re-compression stroke, chemiluminescence images of the gasoline engine indicated the presence of oxidation reactions. In the presence of spark discharge, the location of charge ignition was dominated by spark discharge at the center of cylinder while simultaneous autoignition sites were found around the periphery of the combustion chamber for non-spark-assisted ignition.

Materials Noise, Vibration and Harshness Parts and Components Power and Propulsion Quality, Reliability and Durability Safety Tests and Testing Transportation Systems Vehicles and Performance Other Options Papers by Event SAE Home > Papers> By Event> SAE 2010 World Congress & Exhibition Model Predictive Control of a Combined EGR/SCR HD Diesel Engine Date Published: 2010-04-12Paper Number: 2010-01-1175 DOI: 10.4271/2010-01-1175 Author(s): Claes Westerlund - Scania CV AB Bjorn Westerberg - Scania CV AB Ingemar Odenbrand - Lund Univ. Rolf Egnell - Lund Univ. View All CollapseAbstract Achieving upcoming HD emissions legislation, Euro VI / EPA 10, is a challenge for all engine manufacturers. A likely solution to meet the NO x limit is to use a combination of EGR and SCR. Combining these two technologies poses new challenges and possibilities when it comes to optimization and calibration.

The most common fan model to use in commercial CFD software today is the Multiple Reference Frame (MRF) model. This is at least valid for automotive under hood applications. Within the industry, for this typical application, this model is commonly known to under predict performance. This under prediction has been documented by the authors’ of this paper in SAE paper 2009-01-0178 and VTMS paper 2009-01-3067. Furthermore has this been documented by S.Moreau from Valeo in “Numerical and Experimental Investigation of Rotor-Stator Interaction in Automotive Engine Cooling Fan Systems”, ETC, 7th European Conference on Turbomachinery, 2007. In preceding papers a specific methodology of use has been documented and it has been shown that the MRF model under predicts performance for the airflow in a cooling system commonly with 14% in volumetric flow rate. This is for a system dominated by inertial effects. These 14% was shown to apply across fans of different sizes and designs hence illustrating a consistency of the fan model. In paper 2009-01-3067 a different methodology of use was documented which decreased the under prediction to 8%. In this paper the study has continued and is now presenting a more successful methodology of use which essentially removes the under prediction of the fan MRF model for most of fan operation, taking it for axial flow conditions within reasonable capabilities of reproducing tested geometry in a simulation environment, i.e. a difference of 0-1% between measurements and simulations.

Nowadays application of light alloys like aluminium in automobile industry has found a striking role. Higher strength over weight ratio which causes lower fuel consumption seems to be the first reason. Also some other reasons like ease of manufacturing, protection against corrosion and ease of recycling are other motivations for car designers to use various aluminium alloys as much as possible. Due to lack of variable thickness tubes, they have not found a lot of applications in the car component design. This paper aims to introduce these types of tubes to automotive industry. Also these tubes are one of the essential elements in the complementary processes like tube hydroforming and cause ease of production and decreasing risk of scrap in manufacturing cycles. Tube drawing is one of the mostly used methods for reducing thickness and/or diameter of tubes which, can be classified in four categories like sinking (without mandrel), float mandrel, fixed mandrel and ultrasonically moving mandrel. This paper presents numerical studies that have been done on the drawing tubes with variable thickness. The influence of process variables on material thinning and formability in 63.5mm outer diameter, 2.62 mm wall thickness AA6063 aluminium alloy tube, were investigated and optimised. Validation of the numerical simulation on the different parameters setting will be performed by comparing the final shape and deformation, measured from the tested part. Acceptable agreement between numerical and experimental results was observed.

Due to titanium’s excellent strength-to-weight ratio and high corrosion resistance, titanium and its alloys have great potential to reduce energy usage in vehicles through a reduction in vehicle mass. The mass of a road vehicle is directly related to its energy consumption through inertial requirements and tire rolling resistance losses. However, when considering the manufacture of titanium automotive components, the machinability is poor, thus increasing processing cost through a trade-off between extended cycle time (labor cost) or increased tool wear (tooling cost). This fact has classified titanium as a “difficult-to-machine” material and consequently, titanium has been traditionally used for application areas having a comparatively higher end product cost such as in aerospace applications, the automotive racing segment, etc., as opposed to the consumer automotive segment. Herein, the problems associated with machining titanium are discussed, and a review of cutting tool technologies is presented that contributes to improving the machinability of titanium alloys. Additionally, nonconventional machining techniques such as High Speed Machining and Ultrasonic Machining are also reviewed. Also discussed are additional factors that need to be considered especially pertaining to the machining of titanium alloys, a crucial one being the non-conformity with standard tool wear models. Subsequently, the results of a controlled milling experiment on Ti-6Al-4V is presented, to evaluate the relationship between certain tool preparation/process parameters and tool wear for a comparison with traditional wear models. INTRODUCTION Titanium is the seventh most abundant metal and the fourth most abundant structural metal in earth’s crust behind aluminum, iron and magnesium. Titanium and its alloys are considered as alternatives in many engineering applications due to their superior properties such as retained strength at elevated temperatures, high chemical inertness and resistance to oxidation. Titanium has traditionally been utilized as a lightweight, very strong and exceedingly corrosion resistant material in the aerospace industry, electric power plants, seawater desalination plants, and heat exchanges. Also, it has been used in industrial applications such as petroleum refining, nuclear waste storage, food processing, pulp and paper plants, and marine applications [1]. Nevertheless, when considering the use of titanium as an automotive component material, there are several conflicting aspects that must be addressed. First of all, the cost of titanium is relatively high in comparison to other common engineering materials such as aluminum, magnesium, and steel. For this reason, it specifically calls for implementation and use only when extreme conditions are to be met, such as in the aerospace industry. The main reason for the increased cost is due to the limited demand from other market segments, thus making the extraction of the titanium ore expensive. Also, the processing costs for converting the ore into commercially usable titanium and its alloys is extensive and requires special processing procedures and involves vast batch production and careful process control, making them difficult to automate. Second, the difficulty in efficiently manufacturing titanium components has a significant adverse effect on processing cost which is mainly due to its low modulus of elasticity and high yield stress. Another manufacturing concern that arises during the machining of titanium is its susceptibility to work hardening during the cutting process and its tendency to react with many cutting tool materials causing substantial tool wear. Additionally, titanium has poor thermal conductivity properties, making heat dissipation a problem, again contributing to higher tool wear. Of primary concern however is the lack of material grade development outside the aerospace industry in which most of the alloys are developed for extreme conditions. This severely limits the currently available grades suited for automotive applications. Thus, a suite of lower strength alloys with properties specially catered for commercial automotive use needs to be developed. This paper examines most of the issues traditionally associated with the machinability of titanium and titanium alloys. As mentioned before, some methodologies and techniques are recommended for mitigating the non-desirable effects during titanium processing and analyzed in more detail, is its unique tool wear characteristics especially in light of manufacturing automotive components. Thus, this study is expected to primarily assist in the reduction of the processing cost of titanium and its alloys for automotive component manufacture. This will help reduce the operating cost of a road vehicle in terms of better fuel economy due to the reduced mass, which in turn translates to better energy efficiency. TITANIUM IN THE AUTOMOTIVE

This paper describes a strategy to simulate a dynamic model of a vertical takeoff and landing (VTOL) unmanned aerial vehicle (UAV) in flight transition from vertical climb to horizontal flight. Based on unique aerodynamic characteristics from CFD calculation and theoretical method the flight dynamics of ducted fan UAV is able to be modeled and simulated accurately. MATLAB/Simulink VRealm Builder is a design and modeling software tool for air vehicles that is capable of modeling the performance and flight dynamics during the conceptual and preliminary stage of aircraft design. To develop a control strategy, modeling and simulation of flight dynamics of ducted fan UAV is This paper describes a strategy to simulate a dynamic model of a vertical takeoff and landing (VTOL) unmanned aerial vehicle (UAV) in flight transition from vertical climb to horizontal flight. Based on unique aerodynamic characteristics from CFD calculation and theoretical method the flight dynamics of ducted fan UAV is able to be modeled and simulated accurately. MATLAB/Simulink VRealm Builder is a design and modeling software tool for air vehicles that is capable of modeling the performance and flight dynamics during the conceptual and preliminary stage of aircraft design. To develop a control strategy, modeling and simulation of flight dynamics of ducted fan UAV is necessary, because it not only can be applied to optimize dynamic model, but also be used to ensure the dynamic model match with control law.

This paper presented methods to determine the aerodynamic forces that act on an aircraft wing during flight. These methods are initially proposed for a simplified two degree-of-freedoms airfoil model and then are extensively applied for a multi-degree-of-freedom airfoil system. Different airspeed conditions are considered in establishing such methods. The accuracy of the presented methods is verified by comparing the estimated aerodynamic forces with the actual values. A good agreement is achieved through the comparisons and it is verified that the present methods can be used to correctly identify the aerodynamic forces acting on the aircraft wing models. INTRODUCTION During flight, aircraft wings always subject to varying aerodynamic loadings and as a consequence, generate varying structural responses. The varying aerodynamic loadings and structural responses are coupled to create a complicated vibration effect known as structural coupling dynamics. This effect can significantly reduce the aircraft’s service life. Even worse, sometimes the sustained vibration at natural frequencies of airfoils may lead to catastrophic structural failure. Recently, a number of researchers have dedicated tremendous effort to developing and choosing light material for the aircraft in order to obtain effective loading capacity. However, as the aircraft speed continues to increase, its structural flexibility is becoming a dominant concern in aircraft design and causing serious flutter in the airfoil and other components. Considering a typical cross-sectional plane of an airfoil, the gravity center G is usually located at 42% ~ 45% of the chord line, and the elasticity center is located at 38% ~ 40% of the chord line (Fig. 1). The gravity center is not coincident with the elastic center, which results in another coupling effect between the translational and rotational degree-of-freedoms of the aircraft wing. This coupling effect and the aforementioned structural coupling dynamics make it too difficult to correctly determine the aerodynamic forces acting on the aircraft wings. The current methods of studying the dynamic response of the aircraft structure consider the structural model and the aerodynamic model separately and therefore fails to precisely simulate the two coupling effects. In this paper, new methods are presented to determine the aerodynamic forces acting on aircraft wings during flight, which considers the model’s structural elasticity and aerodynamics as a combined mathematical system. The methods are initiated based on a simplified two degree-of-freedoms airfoil system and then they will be applied for a finite element aircraft wing model, which is a multi-degree-of-freedom system. The accuracy of the present methods will be verified by comparing the estimated aerodynamic forces with the actual values.

With the recent development of a multi spindle flex track drilling systems for aerospace applications, the challenges of testing and implementation on existing airplane programmes require unique technical methodologies and solutions. This paper discusses the technical approach, problems encountered and methodologies/solutions used to successfully implement a multi spindle flex track drilling system for circumferential splice drilling on the 777 airplane. The multi spindle system uses varieties of flex track carriages attached to flexible vacuum tracks for wide inside drilling. The hardware and software challenges encountered during the interfacing of the multi spindles are discussed as well as the complex problem of indexing and locating all detailed components of the splice accurately and with high repeatability. Design changes completed to make the equipment production ready along with the key hole feature probing hardware (Renishaw, Laser & Vision) and techniques are also presented in this paper. The usage of carbide drills with unique carbide material specification and drill geometry design is presented as part of the tool life optimization process. NC programming techniques and algorithms used to compensate for contour variability on circumferential splices are also discussed. Material handling equipment design and implementation process for this multi spindle flex track drilling cell is provided. The detailed test plan along with the incremental implementation methodology used to establish first a stable, then a robust and ultimately a completely optimized process with all technical variables accounted for is presented through the body of this paper.

Around 15% of traffic accident casualties in Europe are pedestrians. To date, most of the studies carried out only provide statistical information on the problem and few in-depth studies provide countermeasures which might correct it. There are many studies concerning pedestrian protection, which can be grouped into 'pedestrian modelling', 'biomechanical limits for pedestrians' and 'statistical analysis for pedestrian accidents'. Despite these studies, there is no predictive analysis of the benefits of pedestrian protection systems based on their intrinsic capabilities applied to a real accident sample. This paper describes a methodology for the evaluation of pedestrian protection systems based on the analysis of a wide sample of urban pedestrian accidents. All of them are analysed in-depth and reconstructed with PC-Crash. The effects of the frontal structure of the vehicles and several active systems, such as BAS and Pedestrian Detection Systems are evaluated. The paper includes the description of the methodology followed for a sample of approximately 140 pedestrian urban accidents in three cities of Spain (Madrid, Barcelona and Zaragoza) and the corresponding reconstructions generated with PC-Crash. Then, a methodology to simulate the passive and active improvements (including pedestrian friendly structure, BAS and Pedestrian Detection Systems) is defined and applied to all sample accidents. The results of these new simulations are used to evaluate the benefits of these systems. The main conclusions are discussed, accounting for the limitations of the study, which basically lie in the modelling of the Pedestrian Detection Systems. The methodology proposed in this paper can be applied to other vehicle safety devices to evaluate their effectiveness, based on the analysis of real accidents. All the results presented here come from a project partly funded by the Spanish Ministry of Industry. The full text of this paper may be found at: http://www-nrd.nhtsa.dot.gov/pdf/esv/esv21/09-0376.pdf For the covering abstract see ITRD E145407.

A common fan model to use in automotive underhood simulations is the Multiple Reference Frame (MRF) model and within the industry, for this specific application, this model is well known to under-predict performance. In a former paper, referenced 2009-01-0178, a simple 'speed correction' of the MRF model was proposed by the authors. The correction was shown to apply across different operating speeds for a specific fan. In this paper the generality and limitation of this correction across fans of different type, design and dimensions are investigated. Investigated in this paper is as well the sensitivity of the MRF model to specific methodology of use. In this paper it is shown that the speed correction of 14% proposed in the former paper applies widely, hence, although the MRF model is erroneous the error is consistent. A 680 mm fan of the similar design to the default (750 mm) choice was simulated and tested, in addition a different 750 mm fan with a more mixed flow design was simulated and tested, and the correction of 14% was shown to apply for these two fans as well. Furthermore is it also shown that the consistency of the MRF model applies with a consistent methodology of use; in its design, the MRF model needs a dedicated rotational volume around the rotating part, this needs to be chosen consistently by the end-user of the CFD software to achieve a consistent behavior of the MRF model. In this paper we show the sensitivity to the results done by the specific choice of rotational domain. In this paper a wiser choice of MRF region resulted in a significant drop in error and for this methodology a speed correction of only 8% was necessary.

The now-cancelled Constellation Program included the Orion, Altair, and Lunar Surface Systems project offices. The first two elements, Orion and Altair, were planned to be manned space vehicles while the third element was much more diverse and included several sub-elements. Among other things, these sub-elements were Rovers and a Lunar Habitat. The planned missions involving these systems and vehicles included several risks and design challenges. Due to the unique thermal operating environment, many of these risks and challenges were associated with the vehicles thermal control system. NASA s Exploration Technology Development Program (ETDP) consisted of various technology development projects. The project chartered with mitigating the aforementioned thermal risks and design challenges was the Thermal Control System Development for Exploration Project. These risks and design challenges were being addressed through a rigorous technology development process that was planned to culminate with an integrated thermal control system test. Although the technologies being developed were originally aimed towards mitigating specific Constellation risks, the technology development process is being continued within a new program. This continued effort is justified by the fact that many of the technologies are generically applicable to future spacecraft thermal control systems. The current paper summarizes the development efforts being performed by the technology development project. The development efforts involve heat acquisition and heat rejection hardware including radiators, heat exchangers, and evaporators. The project has also been developing advanced phase change material heat sinks and performing a material compatibility assessment for a promising thermal control system working fluid. The to-date progress and lessons-learned from these development efforts will be discussed throughout the paper.

Sublimators have been used for heat rejection in a variety of space applications including the Apollo Lunar Module and the Extravehicular Mobility Unit (EMU). Sublimators typically operate with steady-state feedwater utilization at or near 100%. However, sublimators are currently being considered to operate in a cyclical topping mode during low lunar orbit for Altair and possibly Orion, which represents a new mode of operation. This paper will investigate the feedwater utilization when a sublimator is used in this nontraditional manner. This paper includes testing efforts to date to investigate the Orbit-Averaged Feedwater Utilization (OAFU) for a sublimator.

This paper presents the findings of the trade study to evaluate carbon dioxide (CO2) sensing technologies for the Constellation (Cx) space suit life support system for surface exploration. The trade study found that nondispersive infrared absorption (NDIR) is the most appropriate high Technology Readiness Level (TRL) technology for the CO2 sensor for the Cx space suit. The maturity of the technology is high, as it is the basis for the CO2 sensor in the Extravehicular Mobility Unit (EMU). The study further determined that while there is a range of commercial sensors available, the Cx CO2 sensor should be a new design. Specifically, there are light sources (e.g., infrared light emitting diodes) and detectors (e.g., cooled detectors) that are not in typical commercial sensors due to cost. These advanced technology components offer significant advantages in performance (weight, volume, power, accuracy) to be implemented in the new sensor. The exact sensor design (light source, transmitting optics, path length, receiving optics and detector) will be specific for the Cx space suit and will be determined by the performance requirements of the Cx space suit. The paper further identifies specifications for some of the critical performance parameters as well as discussing the engineering aspects of implementing the sensor into the Portable Life Support System (PLSS). The paper then presents testing results from three CO2 sensors with respect to issues important to Extravehicular Activity (EVA) applications; stability, humidity dependence and low pressure compatibility. The three sensors include two NDIR sensors, one commercial and one custom-developed by NASA (for a different purpose), and one commercial electrochemical sensor. The results show that both NDIR sensors have excellent stability, no dependence on ambient humidity (when the ambient temperature is above the dew point) and operate in low pressure conditions and after being exposed to a full vacuum. The commercial electrochemical sensor was not suitable for the Cx space suit for surface exploration. Finally, the paper identifies a number of techniques currently under development that offer significant advantages for EVA applications. These include miniaturized, room temperature, solid electrolyte systems and advanced optical detectors.

An amine-based carbon dioxide (CO2) and water vapor sorbent in pressure-swing regenerable beds has been developed by Hamilton Sundstrand and baselined for the Orion Atmosphere Revitalization System (ARS). In two previous years at this conference, reports were presented on extensive Johnson Space Center (JSC) testing of the technology in a representative environment with simulated human metabolic loads. The next step in developmental testing at JSC was to replace the simulated humans with real humans; this testing was conducted in the spring of 2008. This first instance of human testing of a new Orion ARS technology included several cases in a sealed Orion-equivalent free volume and three cases using emergency breathing masks connected directly to the ARS loop. Significant test results presented in this paper include comparisons between the standard metabolic rates for CO2 and water vapor production published in Orion requirements documents and real-world rate ranges observed with human test subjects. Also included are qualitative assessments of process flow rate and closed-loop pressure-cycling tolerability while using the emergency masks. Recommendations for modifications to the Orion ARS design and operation, based on the test results, conclude the paper.

This joint mobility KC lecture included information from two papers, "A Method for and Issues Associated with the Determination of Space Suit Joint Requirements" and "Results and Analysis from Space Suit Joint Torque Testing," as presented for the International Conference on Environmental Systems in 2009 and 2010, respectively. The first paper discusses historical joint torque testing methodologies and approaches that were tested in 2008 and 2009. The second paper discusses the testing that was completed in 2009 and 2010.