Daimler (Japan)

<div class="htmlview paragraph">The purpose of the 4-SPACE (<b>4-S</b>troke <b>P</b>owered gasoline <b>A</b>uto-ignition <b>C</b>ontrolled combustion <b>E</b>ngine) industrial research project is to research and develop an innovative controlled auto-ignition combustion process for lean burn automotive gasoline 4-stroke engines application. The engine concepts to be developed could have the potential to replace the existing stoichiometric / 3-way catalyst automotive spark ignition 4-stroke engines by offering the potential to meet the most stringent EURO 4 emissions limits in the year 2005 without requiring DeNOx catalyst technology. A reduction of fuel consumption and therefore of corresponding CO2 emissions of 15 to 20% in average urban conditions of use, is expected for the « 4-SPACE » lean burn 4-stroke engine with additional reduction of CO emissions.</div> <div class="htmlview paragraph">This paper describes the first set of results of different experimental and numerical studies aiming to get such new combustion process in 4-stroke engines within the framework of this European consortium.</div> <div class="htmlview paragraph">One of the target of this consortium driven by IFP, is to develop a 4-stroke gasoline engine running conventionally at high load (with a normal compression ratio and without any intake air heating) and able to achieve <b>C</b>ontrolled <b>A</b>uto-<b>I</b>gnition (CAI) process at part load by reproducing the 2-stroke internal conditions (internal EGR rate and fluid dynamic control, temperature level…) favorable to this particular combustion process. For this purpose and as a starting point of the work program, a production 2-stroke engine known for its part load auto-ignition behavior is fully studied. Such work is focused on the analysis of in-cylinder conditions prior to auto-ignition using combined experimental testing, 3D CFD computations and optical diagnostics.</div> <div class="htmlview paragraph">From this analysis, 1D CFD computations have been extensively performed to evaluate the possible 4-stroke concepts able to reproduce internal conditions favorable to CAI. Then, the most “promising” configurations have been experimentally investigated. Encouraging preliminary results have already shown that NOx emissions are reduced by 10 to 40 times and the fuel economy is improved by 8 to 10% when compared with stoichiometric reference conditions.</div> <div class="htmlview paragraph">Other ways of getting auto-ignition of the lean fresh mixture are also explored by the project partners. The effects of several parameters, such as the fuel composition, the engine compression ratio, the intake air temperature level, etc… are also included in the research program. Thus, to analyze better analyze intrinsic auto-ignition process, specific tools as for example Rapid Compression Machine have been developed. Different fuels at various initial conditions (e.g. temperature, excess air) have been tested and compared, for example in terms for example of combustion rate and auto-ignition delay. Results obtained contribute to the better understanding of the auto-ignition process.</div> <div class="htmlview paragraph">Preliminary visualization results from specially designed single cylinder engines (2-stroke and 4-stroke) have been obtained for controlled auto-ignition combustion. The effect of charge stratification is briefly discussed.</div>

Many recent technological advances have helped to pave the way forward for fully autonomous vehicles. This special issue explores three aspects of the self-driving car revolution: a historical perspective with a focus on perception for autonomous vehicles, how government policy will impact self-driving cars technically and commercially, and how cloud-based infrastructure plays a role in the future.

Evolutionary testing is an effective technique for automatically generating good quality test data. However, for structural testing, the technique degenerates to random testing in the presence of flag variables, which also present problems for other automated test data generation techniques. Previous work on the flag problem does not address flags assigned in loops.This paper introduces a testability transformation that transforms programs with loop--assigned flags so that existing genetic approaches can be successfully applied. It then presents empirical data demonstrating the effectiveness of the transformation. Untransformed, the genetic algorithm flounders and is unable to find a solution. Two transformations are considered. The first allows the search to find a solution. The second reduces the time taken by an order of magnitude and, more importantly, reduces the slope of the cost increase; thus, greatly increasing the complexity of the problem to which the genetic algorithm can be applied. The paper also presents a second empirical study showing that loop--assigned flags are prevalent in real world code. They account for just under 11% of all flags.

<div class="htmlview paragraph">Novel testing procedures and analytical methodologies to assess the performance of hybrid electric vehicle batteries have been developed. Tests include both characterization and cycle life and/or calendar life, and have been designed for both Power Assist and Dual Mode applications. Analytical procedures include a battery scaling methodology, the calculation of pulse resistance, pulse power, available energy, and differential capacity, and the modeling of calendar- and cycle-life data. Representative performance data and examples of the application of the analytical methodologies including resistance growth, power fade, and cycle- and calendar-life modeling for hybrid electric vehicle batteries are presented.</div>

<div class="htmlview paragraph">Pollutant emissions and specifically NO and soot are one of the most important problems that engineers have to face when developing heavy duty DI diesel engines. Two main strategies exist as options for their control, reduction inside the engine cylinder using advanced combustion and fuel injection technologies and use of after-treatment systems. In the present work it is examined the use of EGR to control the formation of NO inside the cylinder of an engine with extremely high peak pressure. The work is applied on a single cylinder truck test engine developed under a project funded by the European Community focusing on the improvement of heavy duty DI diesel engine efficiency using increased injection timing. Use is made of a simulation model to predict the effect of more advanced injection timing on engine performance and emissions. The model has been modified to include the effect of EGR used to c ontrol the formation of NO which is considerably increased at high injection timings. Experimental results from the engine without EGR at various engine operating conditions and injection timings have been used to determine the baseline for evaluating the effect of EGR on engine performance and emissions and to validate the model used. Various engine conditions are examined covering the operating range of the engine. Using the simulation model results are produced concerning engine performance, i.e. cylinder pressure, heat release, BSFC and tailpipe values for NO and soot. For each engine operating condition various percentages of EGR are examined and their impact on engine BSFC and pollutant emissions is determined. As observed the use of EGR results to a slight increase of BSFC, a reduction of NO and an increase of soot emissions. Due to the last it was decided to examine using the simulation code the possibility for increasing boost pressure to maintain the overall AFR the same as in the case without EGR. The findings of the investigation are interesting since it is revealed that using an increased boost pressure soot is not increased seriously with EGR, BSFC is maintained fairly the same while the reduction of NO is slightly lower but in any case very significant compared to operation without EGR. Results are also provided concerning the distribution of thermodynamic parameters and pollutants inside the fuel jet revealing the actual effect of EGR on their formation. Especially important is the information obtained when comparing values under EGR operation at constant AFR with the ones obtained with a constant boost pressure since a better explanation for the observed results is provided helping us understand the actual effect of EGR on the pollutant formation mechanism.</div>

<div class="htmlview paragraph">A greater understanding of where fuel energy is being demanded from a vehicle system standpoint is necessary for developing more fuel efficient vehicles. This paper presents an overview of the development and application of a vehicle energy analysis methodology and a MATLAB®/Simulink® based tool that uses empirical data and first principles to identify vehicle subsystem energy supply and demand. An accurate analysis requires the tool to be populated with chassis dynamometer drive cycle data as well as vehicle and component information. The tool can be used to investigate vehicle system energy requirements, prevailing fuel economy factors, and incremental hypothetical fuel saving scenarios that could not otherwise be measured due to inherent test-to-test variability.</div>

Abstract Over the last few years, the concept of agility has become increasingly popular in organizations. Companies are hoping to foster speed, adaptability, and innovation by rolling out an agile strategy, implementing agile methods, and creating an agile mind-set among leaders and employees. There is, however, much ambiguity about what the concept of agility entails and how it can be successfully implemented in an organization. The purpose of this practice-focused paper is to organize the extant agility literature for readers by giving an overview of different definitions of agility; outlining evidence-based factors that contribute to agility at the individual, team, and organizational levels; and describing three practical examples at a large German car company. Finally, the authors suggest steps that organizations can take to increase agility in their workforce.

In this paper, we introduce a novel self-supervised visual representation learning method which understands both images and videos in a joint learning fashion. The proposed neural network architecture and objectives are designed to obtain two different Convolutional Neural Networks for solving visual recognition tasks in the domain of videos and images. Our method called Video/Image for Visual Contrastive Learning of Representation(Vi <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> CLR) uses unlabeled videos to exploit dynamic and static visual cues for self-supervised and instances similarity/dissimilarity learning. Vi <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> CLR optimization pipeline consists of visual clustering part and representation learning based on groups of similar positive instances within a cluster and negative ones from other clusters and learning visual clusters and their distances. We show how a joint self-supervised visual clustering and instance similarity learning with 2D (image) and 3D (video) CovNet encoders yields such robust and near to supervised learning performance.We extensively evaluate the method on downstream tasks like large scale action recognition, image and object classification on datasets like Kinetics, ImageNet, Pascal VOC’07 and UCF101 and achieve outstanding results compared to state-of-the-art self-supervised methods.

&lt;div class="htmlview paragraph"&gt;Improving catalyst light-off characteristics during cold start and reducing engine-out (more accurately converter-in) emissions prior to catalyst light-off have been regarded as the keys to meeting future stringent emissions regulations. Many technologies and control strategies have been proposed, and some of them have already been incorporated into production, to address these issues. Among these, secondary air injection received a lot of attention. This study was initiated to investigate the thermal and chemical processes associated with secondary air injection inside the exhaust system in order to maximize the simultaneous benefit of improving catalyst light-off performance and reducing converter-in emissions. The effects of several design and operating parameters such as secondary air injection location, exhaust manifold design, spark timing, engine enrichment level, and secondary air flow rate were carefully examined. It was found that proper design and optimization of secondary air injection can significantly improve catalyst light-off characteristics and reduce converter-in HC emissions.&lt;/div&gt;

&lt;div class="htmlview paragraph"&gt;The emergence of new technology of fuel efficient dual clutch, electronically shifted, automatic transmissions employs conventional manual transmission architecture where synchronizers play a major role of precise gear shifting. Although shift quality is not directly affected by the synchronizers, smooth and quick transition of gears, including upshift, downshift, and skip shift is logically a significant factor in accomplishing the fuel economy objective.&lt;/div&gt; &lt;div class="htmlview paragraph"&gt;DCT design with dry clutches is feasible in low torque applications with manageable thermal capacity and clutch wear, whereas wet clutches are used in high torque applications that can manage heat with cooling. The synchronizer design is critical in both applications substantially affected by system efficiency including clutch drag, bearing frictional losses, and fluid churning losses, plus energy losses due to friction and deflection in shift and clutch actuation mechanism. Hence synchronizer design must satisfy the following two major demands:&lt;/div&gt; &lt;div class="htmlview paragraph"&gt; &lt;ol class="list nostyle"&gt; &lt;li class="list-item"&gt;&lt;span class="li-label"&gt;1&lt;/span&gt;&lt;div class="htmlview paragraph"&gt;Synchronization torque essentially must be greater than index torque at every point during synchronization event to prevent clash or grating noise.&lt;/div&gt;&lt;/li&gt; &lt;li class="list-item"&gt;&lt;span class="li-label"&gt;2&lt;/span&gt;&lt;div class="htmlview paragraph"&gt;Index torque must be high and provide ability to shift in cold conditions to overcome the total transmission losses to insure smooth gear shiftability.&lt;/div&gt;&lt;/li&gt; &lt;/ol&gt; &lt;/div&gt; &lt;div class="htmlview paragraph"&gt;The above requirements establish the boundary limits for index torque to be smaller than synchronization torque and greater than total transmission drag.&lt;/div&gt; &lt;div class="htmlview paragraph"&gt;Increasing index torque by reducing the pointing angle to compensate for clutch drag and total transmission losses could conceivably require increasing synchronization torque by increasing cone coefficient of friction to safeguard (gear shift) against clash.&lt;/div&gt; &lt;div class="htmlview paragraph"&gt;The relationship of above significant parameters for smooth gear transition is mathematically established and experimentally verified. Synchronization torque measurement procedure is known, but index torque is usually not measured. For verification purposes a measurement method was formulated and a fixture was built accordingly. Calculated and measured drag torque values were observed to have good correlation with coefficient of friction between sleeve and ring chamfer surfaces as variable.&lt;/div&gt; &lt;div class="htmlview paragraph"&gt;The test results manifest that in a dual clutch transmission precise and quick shifting is elemental to the function of the transmission, and system efficiency is fundamental to both fuel efficiency and synchronizer function.&lt;/div&gt;

The Connected-Car Prototyping Platform provides both a back end for applications interacting with connected cars and an abstraction of such connected devices for developers. It also provides services such as identity management and data storage. Its main purposes are experimentation, prototyping, evaluation of ideas, and reduction of time-to-market for successful applications.

&lt;div class="htmlview paragraph"&gt;The effect of forming strains on the fatigue behavior of an automotive mild steel, interstitial free steel, was studied after being prestrained by balanced biaxial stretch and plane strain. In the long life region, higher than 5×10&lt;sup&gt;5&lt;/sup&gt; reversals, prestrain improves fatigue resistance. In the short life region, prestrain reduces fatigue resistance. At even shorter fatigue lives, the detrimental effect of prestrain diminishes. For plane strains, the fatigue behavior is anisotropic. In the direction perpendicular to the major strain, the steel exhibits much better fatigue resistance than in the direction parallel to the major strain.&lt;/div&gt;

&lt;span class="label"&gt;1.0&lt;/span&gt; &lt;div class="htmlview paragraph"&gt;The manual transmission synchronizer design has been a real challenge and is usually referred to as a myth and black magic. A mathematical algorithm and dimensioning and tolerancing scheme has been developed to dispel this myth.&lt;/div&gt; &lt;div class="htmlview paragraph"&gt;A unique and logical user-friendly method for designing synchronizer is devised. The knowledge that existed in the public domain is advanced to higher level to show that the design and calculations of physical parameters must go hand in hand.&lt;/div&gt; &lt;div class="htmlview paragraph"&gt;The paper attempts to demonstrate the fact that the calculations of synchronizer physical parameters should be supported by scrupulously dimensioning and tolerancing the components design to achieve the intended functional objective.&lt;/div&gt; &lt;div class="htmlview paragraph"&gt;A mathematical algorithm is developed which facilitates establishing the sleeve and blocker ring pointing angle relationship with the synchronizer size, coefficient of friction, cone torque, and index torque. The relationship is presented graphically in a unique manner identifying the clash and hard shift zones. As such, it allows sizing the synchronizer and selection of the parameters for a given application for comfortable shiftability between the two extremes of clash and hard shift.&lt;/div&gt; &lt;div class="htmlview paragraph"&gt;Synchronization episode is separated in to the following six distinct events:&lt;/div&gt; &lt;div class="htmlview paragraph"&gt; &lt;ul class="list nostyle"&gt; &lt;li class="list-item"&gt;&lt;span class="li-label"&gt;Event I&lt;/span&gt;&lt;div class="htmlview paragraph"&gt;Strut contacts blocker ring&lt;/div&gt;&lt;/li&gt; &lt;li class="list-item"&gt;&lt;span class="li-label"&gt;Event II&lt;/span&gt;&lt;div class="htmlview paragraph"&gt;End of strut loading, strut out of detent&lt;/div&gt;&lt;/li&gt; &lt;li class="list-item"&gt;&lt;span class="li-label"&gt;Event III&lt;/span&gt;&lt;div class="htmlview paragraph"&gt;Sleeve point hits ring point, ring clocked&lt;/div&gt;&lt;/li&gt; &lt;li class="list-item"&gt;&lt;span class="li-label"&gt;Event IV&lt;/span&gt;&lt;div class="htmlview paragraph"&gt;Sleeve chamfer passes through ring chamfer&lt;/div&gt;&lt;/li&gt; &lt;li class="list-item"&gt;&lt;span class="li-label"&gt;Event V&lt;/span&gt;&lt;div class="htmlview paragraph"&gt;Sleeve tooth point contacts clutching tooth point&lt;/div&gt;&lt;/li&gt; &lt;li class="list-item"&gt;&lt;span class="li-label"&gt;Event VI&lt;/span&gt;&lt;div class="htmlview paragraph"&gt;Sleeve tooth chamfer passes through gear clutching tooth chamfer&lt;/div&gt;&lt;/li&gt; &lt;/ul&gt; &lt;/div&gt; &lt;div class="htmlview paragraph"&gt;Arithmetic stack and calculations are utilized to iteratively dimension and tolerance the components for each event so functional harmony is achieved in concert with the selected physical parameters. Event charts are presented with illustrations and necessary stack for dimensioning and tolerancing the synchronizer components. The components that play significant role in each event are identified and related to specific physical parameter.&lt;/div&gt;

&lt;div class="htmlview paragraph"&gt;To improve vehicle launch feeling, the powertrain torque output needs to be largely increased. Compared with modifications to engine, transmission, and axle, one of the most inexpensive ways of achieving this goal is to modify the torque converter to get a higher stall torque ratio. In other applications, in order to lower engine speed for better fuel economy, and to match with a higher output engine, a converter with higher torque capacity (lower K factor) is also often desired. In some case of small-volume production, the torque converter modifications are limited to the stator only in order to reduce the manufacturing cost. In the present study, the engineering CFD simulations were used to develop new stators for stall torque ratio and K factor improvement. The flow fields of both baseline and modified torque converters were simulated. The overall performances of the converter were calculated from the flow field data, and correlated with the dyno test data. The flow fields are interpreted to explain the fluid dynamic reasons of improvement. One-dimension rationales to improve performances of converter are also presented and discussed in this paper.&lt;/div&gt;

&lt;div class="htmlview paragraph"&gt;This paper describes a program of coastdown and wind tunnel tests conducted with the objective of establishing a correlation between the aerodynamic drag force measured at the Lockheed-Martin Low-Speed Wind Tunnel (LSWT) and that inferred from coastdown results on the test track. The result of this correlation establishes, in principle, the capability to project what the aerodynamic drag force inferred by a future coastdown test will be (for a future, as-yet unavailable property) based on a current database of wind tunnel results. The correlation is accompanied by a rigorous uncertainty analysis to assess the quality of the correlation and its supporting data.&lt;/div&gt;

This paper first summarizes progress to date in truck safety-related technology. It then examines opportunities for advanced collision techniques, including electronic braking, object detection, and driver monitoring. The authors discuss the differences between active and passive safety systems. The paper concludes with a discussion on governmental roles and the need for consistent standards.

Evolutionary testing is an effective technique for automatically generating good quality test data. However, for structural testing, the technique degenerates to random testing in the presence of flag variables, which also present problems for other automated test data generation techniques. Previous work on the flag problem does not address flags assigned in loops.This paper introduces a testability transformation that transforms programs with loop--assigned flags so that existing genetic approaches can be successfully applied. It then presents empirical data demonstrating the effectiveness of the transformation. Untransformed, the genetic algorithm flounders and is unable to find a solution. Two transformations are considered. The first allows the search to find a solution. The second reduces the time taken by an order of magnitude and, more importantly, reduces the slope of the cost increase; thus, greatly increasing the complexity of the problem to which the genetic algorithm can be applied. The paper also presents a second empirical study showing that loop--assigned flags are prevalent in real world code. They account for just under 11% of all flags.

&lt;div class="htmlview paragraph"&gt;Door mirrors have a major impact on wind noise observed at the driver's ear. The mirror distance and angle with respect to the front side glass will influence the front window buffeting characteristics of the vehicle as well. Optimizing the mirror angle to minimize or eliminate buffeting while maintaining acceptable wind noise performance can provide additional customer satisfaction. Changes to the mirror angle were investigated experimentally for both wind noise and buffeting effects. Experimental vehicle interior noise and buffeting data was taken at multiple yaw angles and wind speeds using a full scale aero acoustic wind tunnel. In addition, experimental wind noise attributes for the different mirror angles was also used to determine the optimal angle. The resulting angle measurement will be used as a best practice mirror angle for optimal wind noise and front window buffeting performance on future vehicle programs.&lt;/div&gt;

Conventional VR tracking methods inside a driving vehicle fail out-of-the-box. We present two novel tracking solutions for experiencing a virtual scene on a head-mounted display in a moving vehicle. We leverage advanced vehicle positioning via sensor fusion of existing car sensors to extract an accurate vehicle pose, which we use to mirror car movements virtually. For 6-DoF head-tracking, we exploit IMU-only tracking for two separate approaches - with and without additional hardware. The virtual car, in which the demo user is situated, moves in a virtual urban scene with diverse and appealing VR scenery generated from real world map data.

&lt;div class="htmlview paragraph"&gt;Numerical calculations of the fuel spray structure from a high-pressure swirl injector were used to enable the interpretation of experimental observations obtained in hot, hollow-cone fuel sprays issued into sub-atmospheric-pressure environments. The experiments show that the spray becomes narrower, more compact, but with a relatively long penetration depth. Model input parameters, including the droplet size distribution, early vapor production, and initial cone angle, were modified to determine which spray characteristics are important in recreating observed spray structures. A very small mean droplet diameter is needed to recreate the experimentally observed structure of the high-temperature, low-pressure sprays. Vapor addition to the emerging spray is then required to increase the axial penetration and provide the observed vapor core. Vapor addition, which was used to imitate the rapid vapor production in a flash boiling spray, produces a vapor core along the axis of the spray while increasing axial penetration and decreasing radial penetration, in agreement with experimental images. Finally, an increase of the initial cone angle is required to match the structure near the injector tip, as none of the previous modifications led to a natural change in the cone angle near the injector. The comparison of model and experiments clearly shows that the accurate simulation of evaporating sprays under realistic hot operating conditions in direct-injected stratified engines requires rethinking of the usual inputs: not only is a realistic droplet size and velocity distribution obtained under evaporating conditions required, but also the addition of locally generated vapor.&lt;/div&gt;