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Simultaneous soot mass concentration and primary particle size measurements in the exhaust gas of diesel engines based on laser-induced incandescence (LII)

University Erlangen-Nuremberg-S. Schraml, S. Will, A. Leipertz
  • Technical Paper
  • 1999-25-0167
Published 1999-06-14 by ISATA - Dusseldorf Trade Fair in United Kingdom
Laser-induced incandescence (LII) is introduced as an useful measurement technique for soot emission control of diesel engines, which allows an accurate and simultaneous on-line determination of soot mass concentration and primary particle size, a quantity which is considered to be an important parameter for possible health hazard effects of diesel soot.A compact optical sensor, which does not require any modification of engine or test equipment, is applied to the exhaust pipe and evaluates the soot blackbody radiation after laser heating. For this purpose, a fast digitizer is used to analyse the temporal signal behaviour, detected by a photomultiplier tube. The prompt LII-signal, which had been shown to be a measure for soot mass concentration, was evaluated quantitatively after calibration with a simple line-of-sight extinction measurement. Due tot he fact hat particle cooling is mainly governed by the specific surface area, the signal decay detected some hundred nanoseconds after the initial excitation was evaluated to provide information on primary particle size.As an example, quantitative results are presented for different operating conditions of a passenger car production…

Robust forward kinematic solution for parallel topology robotic manipulator

University of Hull-T. Hall
University of Teesside-S. McLachlan
  • Technical Paper
  • 1999-25-0094
Published 1999-06-14 by ISATA - Dusseldorf Trade Fair in United Kingdom
A parallel topology manipulator design utilising six legs allows six degrees of freedom of the active platform which can be extended to give a Remote Centre of Compliance (RCC) design configuration allowing a point to be compliantly controlled in 3D space.Inverse kinematic calculations are enabled by simple geometry, however due to non-linearities of this design; the forward kinematic solution has been historically problematic.This paper describes a new algorithm, which has run in MathCAD v6.0 and tested against AutoCAD v14 models to extreme movements of the design. In all cases the iteration process converged quickly and robustly. A FORTRAN 90 pertubative solution implemented from the last known position gives iteration solutions, which would converge in near real time suitable for actuator control.Measurement errors in leg lengths, which are geometrically feasibly, will give solutions, which reflect these errors. Errors, which bring about geometry violation, will give converged solutions in the majority of occasions of the form of real and imaginary values.

Evaluating thixoforming for automotive applications

University of Sheffield-A. J. Lowe, K. Ridgway, H. V. Atkinson
  • Technical Paper
  • 1999-25-0099
Published 1999-06-14 by ISATA - Dusseldorf Trade Fair in United Kingdom
Compared to conventional metal forming techniques, thixoforming (a semi- solid processing route) methods have a number of technical and commercial advantages. It has recently been commercialised by automotive component suppliers, but considerable potential for the application of semi-solid processing remains. One obstacle to the adoption of this technology has been the ability of potential automotive users to evaluate the financial implications of these advantages, many of which are considered to be intangible.The University of Sheffield has produced a software package to evaluate the business process implications of the adoption of thixoforming technology within a manufacturing company. This paper describes the thixoforming process, the further opportunities for its application within the automotive industry and the basis behind the evaluation package.

Active suspension control using regenerative evolution strategy

National Technical Univ.-A. E. Kanarachos, N. G. Pantelelis, C. S. Roussis, D. Koulocheris
  • Technical Paper
  • 1999-25-0239
Published 1999-06-14 by ISATA - Dusseldorf Trade Fair in United Kingdom
The active control of a suspension system aims to produce an isolated behavior of the system's spring mass (e.g. increased comfort, increased performance etc.). In the present paper a nonlinear active suspension nonlinear controller corresponding to a third order Taylor series has been designed and optimized for a rough road profile, using a Regenerative Evolution Strategy. Simulation results reveal that the proposed methodology shows excellent performance. Also the robustness of the controller is demonstrated for a variety of driver's seats increasing the capabilities of the proposed methodology and proving it's effectiveness.

Numerical acoustics in the automotive industry

University of Linz-H. Landes, R. Lerch, M. Schinnerl, J. Schöberl
  • Technical Paper
  • 1999-25-0062
Published 1999-06-14 by ISATA - Dusseldorf Trade Fair in United Kingdom
A new simulation tool for numerical acoustics which is based on the FEM/BEM system CAPA and the mesh generator NETGEN is presented. In contrast to the standard approach, which relies on the use of boundary elements, the vibrating structure is embedded in a large, automatically generated finite element mesh. Therewith, the generation of sound by vibrating structures can be computed directly in the time domain. Compared with the standard approach, great improvements especially for weakly damped structures are achieved.

Parametric study on sensitivity of suspension to brake judder using multi- body dynamics model

Hyundi Motor Co.-K. Young-Park, S. K. Kim, Y. I. Yoo
  • Technical Paper
  • 1999-25-0243
Published 1999-06-14 by ISATA - Dusseldorf Trade Fair in United Kingdom
In this study, reduction of suspension sensitivity to brake torque variation is focused on. A rigid multi-body dynamics model, which had been built for vehicle dynamics simulation, was used. Torque at the steering wheel was used as a measure of brake judder, and major factors affecting the suspension sensitivity were identified. The results indicate that longitudinal stiffness of the suspension and gyroscopic effects of the rotating wheel have a close relationship with suspension sensitivity. Modification was made to a prototype car based on the simulation result. Tests were performed to verify the simulation result.

Fuel and emission impacts of heavy hybrid vehicles

Argonne National Laboratory-F. An, F. Stodolsky
US Department of Energy-J. J. Eberhardt
  • Technical Paper
  • 1999-25-0170
Published 1999-06-14 by ISATA - Dusseldorf Trade Fair in United Kingdom
Hybrid powertrains for certain heavy vehicles may improve fuel economy and reduce emissions. Of particular interest are commercial vehicles, typically in Classes 3-6, that travel in urban areas. Hybrid strategies and associated energy/emissions benefits for these classes of vehicles could be significantly different from those for passenger cars. A preliminary analysis has been conducted to investigate the energy and emissions performance of Class 3 and 6 medium-duty trucks and Class 6 school buses under eight different test cycles. Three elements are associated with this analysis: establish baseline fuel consumption and emission scenarios from selected, representative baseline vehicles and driving schedules; identify sources of energy inefficiency from baseline technology vehicles; and assess practical potentials for energy savings and emissions reductions associated with heavy vehicle hybridization under real- world driving conditions. Our analysis excludes efficiency gains associated with such other measures as vehicle weight reduction and air resistance reduction, because such measures would also benefit conventional technology vehicles. Our research indicates that fuel economy and emission benefits of hybridization can be very sensitive to different test cycles.…

Image generation techniques for outdoor scene simulation

Huazhong University of Science and Technology-M. Ding, Z. Sang, T. Zhang
  • Technical Paper
  • 1999-25-0134
Published 1999-06-14 by ISATA - Dusseldorf Trade Fair in United Kingdom
Scene simulation has an important role in numerous application such as the design of machine vision systems, the design of virtual environments and the test and validation of image processing algorithms. Many approaches have been proposed, however the majority of them are intended for indoor scene simulation. The simulation of outdoor scene is more difficult problem due to the influence of weather and temperature conditions. For the simulation of outdoor scenes, a gray level image generation approach based on mean and variance prediction is first presented which simulates the scene under a hypothetical set of weather conditions by using a transformation of the same outdoor scene under a different set of known weather conditions. Secondly, an image synthesis approach via linear interpolation of standard sample images is derived from Kajiya's rendering equation theory. Finally a simulation approach for outdoor scene in rain and fog is given based on the relationship between the point spread function (PSF) and modulation transfer function (MTF) and the quality of imaging. A number of experiments illustrate that the similarity of…

Modelling traffic incidents with SITRAS

University of South Wales-P. Hidas
  • Technical Paper
  • 1999-25-0024
Published 1999-06-14 by ISATA - Dusseldorf Trade Fair in United Kingdom
SITRAS (Simulation of Intelligent TRAnsport Systems) is a microscopic time- interval update simulation model being developed by the authors at the University of New South Wales since 1995. The model is implemented in an object-oriented structure under the Microsoft Windows NT operating system on IBM-compatible personal computer. The main aim of the model is to provide a general evaluation tool for Intelligent Transport Systems applications such as congestion and incident management, public transport priority and dynamic route guidance. The model concepts and specifications, and first applications of the model in the area of incident modelling in urban arterial networks were described in previous papers. SITRAS is currently being further developed as a test-bed for incident management plans for the NSW RTA in Sydney. This paper presents an update of the general development of the model, and presents the latest modelling examples to demonstrate the practical application of the model.

Requirement analysis for E-CAD variant modules

University of Stuttgart-D. Schäfer, O. Eck, D. Roller
  • Technical Paper
  • 1999-25-0206
Published 1999-06-14 by ISATA - Dusseldorf Trade Fair in United Kingdom
In the area of computer aided design for mechanical engineering (MCAD), One of the most important innovations of the last decade has been the introduction of parametric modeling. In this paper parametric modeling will be extended to the field of computers aided design for electrical engineering (ECAD). Here, parametric modeling is employed to realize new kinds of variational design and will release a tremendous potential of cost and time reduction, going along with a considerable improvement of quality. Hence, this technique can be considered as a significant base technology for next generation ECAD systems.It has been investigated in detail what variational design means in the context of electrical engineering, which functionality one really needs, as well as has to be regarded in developing exactly users demand, we have established a special working group of experts from to CAD system developers, CAD users and research fellows.As a result, we achieved a requirement analysis for ECAD specific automatic variant modules from a rather practical point of view that is summarized in this paper.