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The initial design of an aerodynamics package for a Formula SAE car is described. A review of Formula SAE rules relating to aerodynamics is used to develop realistic parameters for the specification of front and rear inverted airfoils, or ‘wings’. This wing package is designed to produce maximum downforce within the stated acceptable limits of increased drag and reduced top speed. The net effect of these wings on a Formula SAE car's performance in the Dynamic Events is then predicted. A companion paper [1] describes in detail, the CFD, wind tunnel and on-track testing and development of this aerodynamics package.

A new human machine interface (HMI) switch control concept was proposed and evaluated with a driver simulator-based simulation analysis as described in the study of Kiyotaka Sasanouchi [1]. This new concept provides an integrated interface for the vehicle driver to operate on-board devices such as audio, multimedia, HVAC, and navigation systems. To further study and evaluate the benefits of the new concept and more importantly the detailed design factors, a prototype system has been developed and then installed in a production vehicle. The experience learned through this development project is presented in this paper. Some key design issues are addressed, including the multi-functional switch design, menu tree optimization, visual feedback display presentation, and vehicle system interface. Results from an internal customer test ride and survey are also presented to demonstrate the performance and benefits of the new HMI concept design.

In this research, driver risk (subjective feeling of danger) during pylon slalom and drift turning was evaluated by measuring the amount of driver perspiration. The result (the product of the amount of maximum perspiration and the perspiration amount area at the unit running time) is believed to correspond to a subjective rating of the feeling of danger. Moreover, a peculiar phenomenon was observed during drift cornering in which a large degree of fear was experienced if there was a possibility that the vehicle might spin, thus considerably increasing the amount of perspiration. Here, perspiration amount area shows the total amount of perspiration, additional to baseline levels, over a given time frame. And, unit running time shows the same as saying ‘averaged over time’

Vehicle manufacturers are increasingly demanding an accurate preemptive clutch actuation device to distribute drive torque to secondary axles/wheels. The primary driver behind the need for accuracy is the desire to affect the vehicle handling through active torque distribution. Additionally, the ability to preemptively apply a clutch, independent of differential axle rotation, is also required to assure vehicle stability from launch on various surfaces. Other requirements of such a torque transfer device include fast response time, low hysteresis, low drag torque, and low mass.

This paper describes the process and simulation tool chain applied to the design for production of a rear axle with a variable torque biasing capability. Based upon a proven core design (successfully demonstrated in 2004) comprising a novel epicyclic gear arrangement, several variants have been proposed using alternative actuation technologies to achieve bi-directional control of torque bias. The specific design described here includes two concentric wet-plate brakes of less than 200 Nm that control the left-right bias of up to 1400 Nm in a compact and modular design. Recorded GPS data was replayed in a vehicle simulation to derive the range of yaw moment that would be usefully generated by the rear axle to control the lane-keeping and slip angle of the vehicle.

With recent advances in microprocessors and data storage technologies, vehicle users can now bring or access large amounts of data in vehicles for purposes such as communication (e.g. e-mail, phone books), entertainment (e.g. music and video files), browsing and searching for information (e.g. on-board computers and internet). The challenge for the vehicle designer is how to design data displays and retrieval methods to allow data search and manipulation tasks by managing driver workload at safe acceptable levels. This paper presents a data retrieval menu system developed to assess levels of screens (depth of menu) that may be needed to select required information when a vehicle is equipped with the capability to access audio files, cell phone, PDA, e-mail and “On-star” type functions.

In-Vehicle Navigation Systems (IVNS) are becoming common in luxury and rental cars, and low cost portable navigation units are popular aftermarket accessories. It is widely accepted that IVNS should be usable and user satisfaction is key to determining the success of IVNS. This paper proposes NaviQ, a user satisfaction evaluation tool for IVNS. Both general aspects of user interface design and specific aspects of IVNS are investigated and covered by NaviQ, and organized in a way such that they can be easily reused in order to build specific user satisfaction questionnaires for other in-vehicle information systems. NaviQ was deployed in nine online IVNS related communities. Survey results are presented and recommendations made.

Three experiments examined the contribution of sound to the perception of performance using audio recordings made on a test track with a vehicle equipped with a continuously variable transmission (CVT) performing four different maneuvers with four transmission settings. Subjects rated the recordings based on their perceptions of power & performance, pleasantness, smoothness, and loudness. On the track, the low calibration setting (including a flat ratio schedule) had been rated higher for power & performance than the high calibration setting (including a rising ratio schedule). In Experiment 1, where subjects were unaware of the maneuver performed, there was no advantage for the low calibration setting; in Experiment 2, where subjects were aware of the maneuver, the power & performance ratings were opposite to those obtained on the test track. In Experiment 3, drivers of performance cars rated the recordings as more pleasant and smoother than did drivers of other vehicles.

Increasing use of engineering thermoplastics in the applications such as load bearing automotive components necessitates accurate characterization and material modeling for predicting part performance using finite-element simulations. Uniaxial tensile test data on glass filled thermoplastic resins exhibit highly nonlinear deformation with no clear demarcation between elastic and plastic regions. Hence, the estimation of modulus and yield stress values, required for the finite element analysis, is invariably through the subjective interpretation of the CAE analyst, which may not be consistent and unique. Use of parameters such as tangent modulus, yield stress and the post yield data calculated at 0.2% strain for finite element computations does not yield good correlations with experimental values. This paper outlines an alternate approach for evaluating material parameters for short glass filled engineering thermoplastics.

The combination of multi purpose software with powertrain specific application codes allows highly flexible simulation models, which are independent on the specific engine concept. Related to the requests those models may be refined or simplified during the simulation process. Finally a fully coupled 3D dynamic simulation including flexible components is performed to assess the engine crankshaft's durability. To take into account the stiffness of the cranktrain components and the cylinder block at first a linear Finite Element Analysis (FEA) simulation is performed. Via modal reduction the complete deformation order information of the FEA simulation are reduced to the necessary information for the dynamic Multi Body System (MBS) simulation [1, 2]. All main boundary conditions of the system, e. g. gas forces, oil temperature or driveline application are taken into account.

The objective of the present work is to establish a validated simulation methodology for air cooling of batteries that can be used in the industrial design process. Therefore an experimental test rig was set up using a pack of prismatic batteries. The flow field is analysed using Particle Image Velocimetry and pressure measurements. First numerical flow calculations focus on the 3D gap flow. The results display a detailed account of the various flow phenomena and their scales that contribute to the complex flow problem of air cooled batteries and they highlight the technical challenges to obtain homogeneous cooling.

CAE tools have been broadly used to capture and predict interactions between dummies and airbags in detail with the advantages of less preparation time for test set-up and less variability in results especially during airbag deployment tests with dummies out of position. But, the time spent to fold airbag mesh, validate CAE airbag models to experiments and long turn-around times have often been a deterrent to fully adopting CAE tools as a effective way to develop airbag performance. It has been a few years since MADYMO implemented Computational Fluid Dynamics, or CFD into an airbag deploying algorithm. In the early stage of MADYMO CFD, there were issues such as a restriction on the maximum number of Euler cells and instability of unfolding airbags, however, with the introduction of MADYMO V6.2. it has improved CFD functionalities (i.e. more realistic predictions and more stable and accurate simulations).

This paper will show the growth of the Global 4x4 market ( Figure 1), and define terms for 4x4, 4WD and AWD. This will allow a way to organize the data and show the growth trends of the AWD segment. This growth can be seen in Figure 2. From this point of view, the vehicle, and technology differences will be shown, both with physical pictures, and schematic architecture diagrams. The focus will be the US 4WD and AWD market from 1997 to 2004, when a significant change occurred from 4WD to AWD architectures. Figure 1 This paper will document the changes that have occurred to bring about the distinct shift towards AWD car based vehicles from truck based 4WD vehicles. It will be clear why the terms were defined as they were when the architectural differences are shown schematically. Figures 25, 26, 27 and 28.

Much energy is lost through excess air flow in and out of process heating equipment. Energy saving opportunities from managing air flow include minimizing combustion air, preheating combustion air, minimizing ventilation air, and reconfiguring openings to reduce leakage. This paper identifies these opportunities and presents methods to quantify potential energy savings from implementing these energy-savings measures. Case study examples are used to demonstrate the methods and the potential energy savings. The method for calculating savings from minimizing combustion air accounts for improvement in efficiency from increased combustion temperature and decreased combustion gas mass flow rate. The method for calculating savings from preheating inlet combustion air consists of fundamental heat exchanger and combustion efficiency equations. This method accounts for the reduction of combustion air flow as fuel input declines, which is often neglected in many commonly-used methods.

This paper describes software developed by Wisconsin Industrial Assessment Center (IAC) for calculations of energy savings that can be obtained by installing adjustable frequency drives (AFD). Regression models for estimating power used at different loads with and without AFD were developed. Actual data for power use is logged and the power use with the AFD is estimated. The two resulting graphs for power use are compared. The difference in the areas under the two curves is the energy savings.

Productivity is a significant issue in the US auto industry that is often viewed as the success or failure that a vehicle assembly plant can make or break their production schedule. In other words, productivity is often looked at in terms of the number of assembled vehicles produced per year. While high production volume is an important indicator in a manufacturing environment, it certainly does not necessarily imply high productivity. By definition, Productivity is the ratio of output (number of vehicles produced) divided by all input resources such as labor, material, capital, overhead, health and energy costs. Improvement in productivity can be achieved in two ways: a reduction of inputs while output remains constant, or an increase in output while inputs remain constant. Energy is the single most controllable cost parameter in the input parameters of the productivity equation.

Finite element based stress analysis and fatigue predictions are practiced routinely in automotive body structural design and development. The accuracy of these simulation results is not fully understood or at least not well documented. Automotive body structures have many kinds of notches, metal thinning due to stamping and cold working etc. Modern fatigue assessment tools do take into account many of these complexities by Neuber corrections, mean-stress correction, critical plane selection, etc. Other challenges exist in the sensitivity to element quality, including warpage, size, element type, interpretation of results, etc. This case study is based on static loading and accelerated fatigue test conducted on a front-end body buck. The stress and fatigue correlations are designed to build confidence in the model and load inputs. The fatigue results are intended to reproduce durability issues that developed during a proving ground test and were then used to verify potential fixes.

The Plastic Valve Cover System (PVCS) should provides a leak proof seal to the cylinder head under engine temperature, isolate the vibrations transmitted from the engine through the cover to the environment, control the crankcase pressure and house the device to separate oil from the blow-by gas. In order to increase the stiffness of PVCS, short glass fibers and minerals are added during the injection molding of the plastic valve cover. The presence of the fibers results in a component with highly anisotropic thermo-mechanical properties that was not accounted in the previously approach [1]. This paper describes the updated CAE approach with the incorporation of the short fiber anisotropy into the design of cylinder head valve covers.

Industrial motor-driven systems consume more than 70% of global manufacturing electricity annually and offer one of the largest opportunities for energy savings. System optimization techniques through the application of existing, commercially available technologies and accepted engineering practices typically achieve energy savings of 20% or more for these systems across all industrial sectors. The optimization opportunities for steam systems are at least equal or greater. Despite the potential benefits, energy savings from these industrial systems have remained largely unrealized by US industry. This paper presents the argument that unless energy efficiency is institutionalized, it will be viewed by corporate managers as something different than the effective and efficient use of labor and material resources. If this institutionalization does not occur, the potential benefits will never be achieved or sustained.

Holographic interferometry has been successfully employed to characterize both static and dynamic behavior of diverse types of structure under stress. Double-exposure pulsed holographic interferometry has been extensively used in performing the vibration analysis and qualitative investigations of deformation of the non-stationary objects. One of the most important advantages of this technique is that it can be used for quantitative measurements of the transient processes (e.g. shock wave propagation). However, in conventional double-pulsed interferometry it is sometimes difficult to get phase information from a single set of holograms. Applying two-reference beam recording set-up to double-exposure pulsed holographic interferometry makes it possible to obtain phase-shifted interferograms from a single interferogram of the tested object and retrieve the phase information for OPD (optical path difference) map creation.