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The directional turn signal is a vital safety feature, and when properly used by the motor vehicle operator, helps prevent countless collisions every day. As important as this safety feature is, its basic means of shut off control remains virtually unimproved since it was first invented more than 65 years ago. It is a mechanical, closed loop control system that still today exhibits functional circumstances where the turn signal either shuts off prematurely or fails to automatically shut off. This paper describes a patented, intelligent, computer controlled turn signal system with no moving parts that uses existing sensors on the vehicle to decide on a situation appropriate turn signal shut off point, thereby resolving nearly all of the turn signal control shortcomings of today’s mechanical method and improves vehicle safety at a potential overall cost savings.

Convection heat transfer coefficients for surfaces of a brake disk are calculated, and effects of design parameters including dimensions and boundary conditions on temperature distributions of brake disks are investigated by using a three-dimensional finite element model. The maximum temperature occurs near the middle of the inner brake plate. The effect of the thickness of the supporting portion on the temperature distribution of brake disks is insignificant. Increasing the disk fillet radius decreases the temperature distribution of the brake.

Recently, an increased emphasis in reducing brake rotor temperature in an effort to increase brake pad life and to reduce brake fade and “hot judder” has been observed. This study examined the effects of changes to a brake system and its environment on the brake equilibrium temperature rise. Initially, a baseline thermal model was correlated to physical test data from a cyclical braking test. This correlated model was then used to study the effects of modifying the rotor, dust shield, wheel, and air deflector on the brake equilibrium temperature rise under the cyclical braking during simulated mountain test schedules.

We have constructed an original brake disc design system by standardizing, automating, and speeding up each design process. This system consists of two steps. In the first step, a designer, without professional knowledge or skills regarding CAE, can easily carry out FEA by manipulating pull-down menus, parametric design, and automated modeling and meshing. Further, our new computer program automatically identifies each eigenmode. It takes less than two hours for a complete FEA of a new design. In the second step, the developed postprocessor makes it easier and faster to compare the simulated results of many design alternatives and determine the optimum solution. Through the accumulation of vast numbers of FEA cases and tests for validation, we have obtained the knowledge of the effects of disc configurations, dimensions, and material properties on resonant frequencies and thermal deflections.

Human performance measures such as discomfort and joint displacement play an important role in product design. The virtual human Santos™, a new generation of virtual humans developed at the University of Iowa, goes directly to the CAD model to evaluate a design, saving time and money. This paper presents an optimization-based workspace zone differentiation and visualization. Around the workspace of virtual humans, a volume is discretized to small zones and the posture prediction on each central point of the zone will determine whether the points are outside the workspace as well as the values of different objective functions. Visualization of zone differentiation is accomplished by showing different colors based on values of human performance measures on points that are located inside the workspace. The proposed method can subsequently help ergonomic design.

This study employs experimental and computational methods to investigate the thermal state of the exhaust manifold of a multi-cylinder turbocharged diesel engine operating under steady-state conditions. The local skin temperatures and surface heat fluxes varied significantly throughout the external surface of the manifold. The augmentation of the local heat flux with increasing load and engine speed may be represented solely by the increase in the fuel mass flow rate. The results of the 1D simulation are in good agreement with the measurements of the exit gas temperatures, skin temperatures, and surface heat fluxes.

An easy-to-use implementation of a Differential Evolution Based Stochastic Optimizer (DEBSO) for nonlinear, multi-modal problems is presented. Using two case studies, we demonstrate that DEBSO is (1) more effective and (2) less sensitive to user defined initial guess values, in finding the global optimum, as compared to that of a gradient based deterministic optimizer. Results from using DEBSO for construction of empirical catalyst maps from pulsator data and estimation of parameters in a diesel oxidation catalyst model are also presented. The effectiveness and efficiency of DEBSO has been compared to other evolution-based optimizers in Appendix A.

This paper presents a hybrid approach for developing a robust model of a diesel oxidation catalyst (DOC). Information from multiple sources including detailed thermal balances, laboratory performance data, phenomenological description of adsorption and desorption in catalyst pores, and experience based correlations are seamlessly integrated using optimization and statistical tools to create an easy-to-use, computationally inexpensive predictive model. Light-off, Light-out, and fuel quench data from a diesel pulsator and engine dynamometer are used for model calibration. The calibrated model predicts cumulative HC and CO tailpipe vehicle emissions as well as DOC NOx outlet composition (NO vs. NO2).

A review of available information on the effect that brake rotor crossdrilling has on brake performance reveals a wide range of claims on the subject, ranging from ‘minimal effect, cosmetic only’ to substantially improving brake cooling and fade resistance. There are also several theories on why brake rotor crossdrilling could improve fade performance, including crossdrill holes providing a path for ‘de-gassing’ of the brake lining material and increasing the mechanical interaction, or ‘grip’ of the lining material on the rotor. This paper reviews three case studies in which the opportunity arose to compare the performance of brake systems with crossdrilled versus non crossdrilled brake rotors in otherwise identical brake corner designs. The effect of brake rotor crossdrilling on brake cooling, brake output, brake fade, wet brake output, and brake wear rates were studied using both on-vehicle and dynamometer data.

The goal of this study was to develop and validate a finite element (FE) model of the Polar-II pedestrian dummy. An upper body model consisting of the head, neck, shoulder, thorax, and abdomen was coupled with a previously validated model of the lower limb The viscoelastic material properties of the dummy components were determined from dynamic compression tests of shoulder urethane, shoulder rubber and abdominal foam. For validation of the entire upper body, the model was compared with NHTSA response requirements for their advanced frontal dummy (Thor) including head and neck pendulum tests as well as ribcage and abdominal impact tests. In addition, the Polar-II full body FE model was subjected to simulated vehicle-pedestrian impacts that recreated published experiments. Simulated head and pelvis accelerations as well as upper body trajectories reasonably reproduced the experiment.

Lean burn after treatment systems using NOX traps for reducing emissions from diesel exhausts require periodic regeneration after each storage stage. Optimising these events is a challenging problem and a model capable of simulating these processes would be highly desirable. This study describes an experimental investigation, which has been designed for the purpose of validating a NOX trapping and regenerating model. A commercial computational fluid dynamics (CFD) package is used, to model NOX trapping and regeneration, using the porous medium approach. This approach has proved successful for three way catalysis modelling. To validate the model a one-dimensional NOX trap system has been tested on a turbocharged, EGR cooled, direct injection diesel engine controlled with an engine management system via DSPACE. Fast response emission analysers have been used to provide high resolution data across the after-treatment system for model validation.

A model was developed for a lean NOx trap (LNT) used in a diesel application. The accuracy of the LNT model was validated using data from flow reactor experiments and vehicle testing. It is demonstrated that the model agrees with the experiments reasonably well on both reactor and vehicle test data. The LNT model was then applied to simulate the NOx emissions at the trap outlet over the FTP cycle, and quantitatively evaluate the effect of inlet CO concentration, inlet H2 concentration, inlet gas temperature, and trap size on NOx conversion performance of the LNT. The LNT model was also integrated with an exhaust pipe model to investigate the impact of engine exhaust configuration on NOx conversion. The integration of the LNT model with the engine exhaust model is valuable in the assessment of engine exhaust configuration and NOx trap performance.

Emissions standards are becoming increasingly harder to reach without the use of exhaust aftertreatment systems such as Selective Catalytic Reduction and particulate filters. In order to make efficient use of these systems it is important to have accurate models of engine-out emissions. Such models are also useful for optimizing and controlling next-generation engines without aftertreatment using for example exhaust gas recirculation (EGR). Engines are getting more advanced using systems such as common rail fuel injection, variable geometry turbochargers (VGT) and EGR. With these new technologies and active control of the injection timing, more sophisticated models than simple stationary emission maps must be used to get adequate results. This paper is focused on the calculation of engine-out NOx and engine parameters such as cylinder pressure, temperature and gas flows.

Given the quantity and severity of head injuries to pedestrians in vehicle-to-pedestrian collisions, human pedestrian finite element models and pedestrian dummies must possess a biofidelic head/neck response to accurately reproduce head-strike kinematics and kinetics. Full-scale pedestrian impact experiments were performed on post-mortem human surrogates (PMHS) using a mid-sized sport utility vehicle and a small sedan. Kinematics of the head and torso were obtained with a six-degree-of-freedom (6DOF) cube, which contained three orthogonally mounted linear accelerometers and three angular rate sensors. The goal of the current study was to present a methodology for analyzing the data obtained from the sensors on each cube, and to use the kinematics data to calculate spatial trajectories, as well as linear velocities and angular accelerations of the head and T1 vertebra.

Previous studies utilizing the Polar-II pedestrian dummy have suggested the need for a more biofidelic pelvis design in order to improve the overall dummy response kinematics. The current Polar-II dummy pelvis is a rigid steel structure. A preliminary version of a modified deformable pelvis equipped with sensors for measuring internal deflection and load has been designed. The goal of this study was to assess the biofidelity of these two pelves in full-scale tests with the Polar-II dummy that mimic lateral pelvic impact tests on PMHS (post-mortem human subjects) reported in the literature. The force - time, deflection - time, and force - deflection histories were compared to new PMHS response corridors determined using a normalization technique. In all tests with both pelves, the initial response (i.e., the first 3 ms to 5 ms following initial dummy - impactor contact) appeared to be totally determined by the mechanical behavior of the flesh.

A finite element (FE) model that can predict impact response and injuries to a human pelvis and lower limb was developed in PAM-CRASH™ by accurately representing human anatomical structures. In our previous study, three-dimensional (3D) geometry of the thigh, leg and knee joint was developed based on MRI scans from a human volunteer. 3D geometry of a bony pelvis created in this study was based on CT scans from a Post Mortem Human Subject (PMHS). The model was validated using published quasi-static and dynamic test results with human pelves and lower limbs. The thigh and leg models were validated against recently published dynamic 3-point bending test results with off-center loading. The validation results showed that this model can reproduce force-deflection and moment-deflection responses of a human thigh and leg in various loading conditions along with average force and moment at fracture.

The effects of several variables on pitting fatigue life of carburized steels were analyzed using a geared roller test machine (GRTM). The material variables that were primarily used to influence retained austenite include aim surface carbon concentration (0.8 % and 0.95 %), alloy (SAE 4320 and a modified SAE 4122), and cold treatment (performed on one material condition per alloy). Testing variables included contact stress in addition to a variation in lambda ratio (oil film thickness/surface roughness), arising from variation in roughness among the machined surfaces. Test results are presented, and differences in performance are considered in terms of material and testing variables. A primary observation from these results is an improvement in contact fatigue resistance apparently arising from cold-treatment and the associated reduction of retained austenite at the surface.

Meeting increasingly stringent targets for vehicle performance, economy and emissions requires a deep understanding of the overall IC engine system behavior and the ability to optimize it considering all control and noise factors and their variations. The tradeoffs in exhaust gas temperature, exhaust valve temperature, engine performance, economy and emissions demand a combination of capable CAE analytical tools and a methodology capable of leading the design to a reliable and robust solution. This paper presents a newly developed methodology that uses a Ford in-house quasi-dimensional combustion model called GESIM (General Engine Simulation Program) and a 3D conjugate heat transfer (CHT) model to predict crank angle resolved exhaust gas temperatures and cycle average valve temperatures in a 6-Sigma context, which considers a wide range of engine factors and their variations, to determine a feasible robust design solution.

A general purpose engine friction model, based on lubrication theory was developed and is presented in this paper. The model takes into account the friction components of the complete ring pack, piston skirt, main/connecting rod bearings and valve train mechanism. Using the developed model, it is possible to predict the complete engine friction (either in crank angle resolution or in engine cycle resolution (Friction Mean Effective Pressure, FMEP), the trajectory of moving components (e.g. piston secondary motion, journal movements in bearings, piston rings motion towards cylinder liner), the pressure field developed by the lubricant. The model was used with data from a four-stroke medium speed marine diesel engine installed in the National Technical University of Athens/Laboratory of Marine Engineering test-bed. The effect of engine speed and engine load on predicted frictional losses was examined and compared with results obtained from other semi-empirical FMEP models.

Rising gas prices at the fuel station, stronger emission requirements at the tail pipe have required more and more fine-tuning of the internal motor components. To support the customers in this difficult task, MAHLE has developed a Power Cell Unit (PCU). The newly introduced lightweight PCU with the MAHLE patented ECOFORM® piston, an optimized pin and high strength material connecting rod offers the customer a complete system that is focused on less reciprocating masses, lower friction and better NVH. The PCU as a unit has been developed for each and every component as well as the interaction of all these components to additionally benefit the customer with less program management, organization, logistic and reduction of development time because all parts are made in-house by MAHLE. An example using a conventional PCU in production versus a weight optimized version is provided for comparative purposes.