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One of the most important safety critical components on cars, trucks, and aircraft is the pneumatic tire. Vehicle tires primarily control stopping distances on wet and dry roads or runways and strongly influence over-steer/under-steer behavior in handling maneuvers of cars and trucks. The inflated tire-wheel assembly also acts as a pressure vessel that releases a large amount of energy when catastrophically deflated. The tire can also serve as a fulcrum, both directly and indirectly, in contributing to vehicle rollover. This course covers these facets of tire safety phenomena.

For automotive engineers involved in crash reconstruction and analysis, a knowledge of basic accident reconstruction principles and techniques is essential, but often insufficient to answer all of the questions posed by design engineers, regulators, and lawyers. This course takes participants beyond the basics of accident reconstruction to physical models and analysis techniques that are unique to the reconstruction of single-vehicle rollover crashes.

The field of motor vehicle rollover research and testing has been one of multiple and varied approaches, dating back to at least the 1930's. The approach has been as simple as tipping a vehicle over at the top of a steep hill ( Wilson et al., 1972 ), to as complex as releasing a vehicle from an elevated roll spit mounted to the rear of a moving tractor and trailer ( Cooper et al., 2001 and Carter et al., 2002 ). Presenter Peter Luepke, P Luepke Consulting

Hybrid technology has the potential to enable dramatic reductions in greenhouse gases (GHG), such as the California goal of reducing GHG by 80 percent from 1990 levels by 2050. As a result it is expected that hybrid systems will occupy a growing proportion of the market. However, introducing a hybrid system in a vehicle may adversely affect the performance of the engine OBD system in monitoring malfunctions impacting pollutant emissions. For example, a hybrid system that reduces time of the engine in idle or deceleration overrun conditions could make a well-performing engine OBD system noncompliant, by reducing in-use frequency of some OBD monitors below acceptable levels. In this presentation, Ricardo will present a process for evaluating the impact that a hybrid system which has been optimised to minimise GHG emission over a specified drive-cycle will have on the effectiveness of engine OBD monitors.

Selective Catalytic Reduction (SCR) catalysts are used to reduce NOx emissions from internal combustion engines in a variety of applications [1,2,3,4]. Southwest Research Institute (SwRI) performed an Internal Research & Development project to study SCR catalyst thermal deactivation. The study included a V/W/TiO2 formulation, a Cu-zeolite formulation and a Fe-zeolite formulation. This work describes NH3 storage capacity measurement data as a function of aging time and temperature. Addressing one objective of the work, these data can be used in model-based control algorithms to calculate the current NH3 storage capacity of an SCR catalyst operating in the field, based on time and temperature history. The model-based control then uses the calculated value for effective DEF control and prevention of excessive NH3 slip. Addressing a second objective of the work, accelerated thermal aging of SCR catalysts may be achieved by elevating temperatures above normal operating temperatures.

The 13 technical papers in collection present work investigating the effect of fuel composition on CI engine performance in terms of combustion efficiency, emissions and engine hardware durability. Variations in fuel composition include: the inclusion of aromatic compounds, the blending of oxygenated components and the use of additives for cetane number improvement and lubricity enhancement.

This technical paper collection focuses on new theory, formulation and modeling of amplitude-, frequency- and temperature-dependent nonlinear components/systems such as rubber and hydraulic mounts or bushings, shock absorbers, and any joint friction/damping; dynamic characterization through lab and field testing; Linearization methodology; Model validation, application, and sensitivity analysis in vehicle system/subsystem simulations; Nonlinear system identification, modeling, and application in testing accuracy improvement, etc.

The 43 papers in this technical paper collection focuses on new theory, formulation and modeling of amplitude-, frequency- and temperature-dependent nonlinear components/systems such as rubber and hydraulic mounts or bushings, shock absorbers, and any joint friction/damping; dynamic characterization through lab and field testing; Linearization methodology; Model validation, application, and sensitivity analysis in vehicle system/subsystem simulations; Nonlinear system identification, modeling, and application in testing accuracy improvement.

Focusing on multibody system modeling and simulation results, rigid and flexible body modeling, mount loads predictions for vehicle body, frame/sub-frame, leaf-spring, exhaust system, driveline, and powertrain, the comparison of modeling techniques between vehicle dynamics simulation and durability loads simulation, optimal development process considering vehicle dynamics and durability loads, data processing and analysis techniques, loads sensitivity analyses for various model parameters, DOE and optimal design techniques for loads minimization, prediction of manufacturing tolerance effects on loads, robust design methods, driver modeling, and FE-based system modeling.

Abstract It is widely understood that the thermal state of a light-duty vehicle at the beginning of a trip influences the vehicle performance throughout the drive cycle. Cold starts, or initial states with component temperatures near ambient conditions, are strongly correlated with reduced vehicle performance and energy efficiency and increased emissions. Despite this understanding, there is little literature available that characterizes initial thermal states beyond empirical studies and simplified analyses of dwell times. We introduce a framework that considers vehicle activity patterns, including the previous drive event, duration of the previous dwell event, and relevant ambient conditions occurring during these events. Moreover, the framework allows for technologies to influence the prominence of cold starts and warm starts.

Abstract The suspension system has been shown to have significant effects on vehicle performance, including handling, ride, component durability, and even energy efficiency during the design process. In this study, a new roll-plane hydraulically interconnected suspension (HIS) system is proposed to enhance both roll and lateral dynamics of a two-axle bus. The roll-plane stability analysis for the HIS system has been intensively explored in a number of studies, while only few efforts have been made for suspension tuning, especially considering lateral plane stability. This article aims to explore the integrated lateral and roll dynamics by suspension tuning of a two-axle bus equipped with HIS system. A ten-degree-of-freedom (DOF) lumped-mass vehicle model is integrated with either transient mechanical-hydraulic model for HIS or the traditional suspension components, namely, shock absorber and anti-roll bar (ARB).

This technical paper collection focuses on analysis and enhancement of vehicle dynamics performance including handling/ braking/ traction characteristics as well as robustness and active stability under the influence of loading, tire forces and intelligent tire technology for enhancing overall vehicle system dynamics and safety characteristics and robustness. Load variations and other uncertainties, impact of system hybridization and electrification on vehicle dynamics and controls are discussed.

This collection of technical papers focus on studies of driver behavior modeling, driving simulator techniques, vehicle ride comfort evaluation and enhancement, test/simulation correlation analysis, vehicle elastomeric component modeling (i.e. bushings, rubber mounts, springs, dampers, seat cushions), passive, semi-active and active suspension systems, suspension seat analysis and modeling techniques, the effect and control of beaming, shaking, impact harshness, brake judder and any other phenomena affecting ride comfort of driver, passengers, goods, etc.

Recent field data have shown that the occupant protection in vehicle rear seats failed to keep pace with advances in the front seats likely due to the lack of advanced safety technologies. The objective of this study was to optimize advanced restraint systems for protecting rear seat occupants with a range of body sizes under different frontal crash pulses. Three series of sled tests (baseline tests, advanced restraint trial tests, and final tests), MADYMO model validations against a subset of the sled tests, and design optimizations using the validated models were conducted to investigate rear seat occupant protection with 4 Anthropomorphic Test Devices (ATDs) and 2 crash pulses.

Dynamic impact test represent various automotive collision conditions. The impact testing recommended practice is intended to recognize the capabilities of autonomous vehicles while at the same time recognizing the vehicle fleet into which they are introduced will consist of non-autonomous vehicles for a considerable period of time. The scope of the document is to cover the range of impact conditions expected taking into account the capabilities of the vehicle and the impact testing technology now available for performance evaluation including virtual and physical testing.

Prevention of catastrophic upset mishaps cannot depend solely on recovery training. The proposed document should complement the training initiatives already in place. As a committee dealing with transport human factors and handling qualities, the output must consider both issues. At the same time, we cannot ignore initial and recurrent training issues and the widespread use of ground-based simulators. The plan would follow the approach taken in the 2003 S-7 white paper but would extend the scope to all forms of LOC, not just repeated rudder reversals. As with the white pa-per, the new document would have sections on transport handling qualities, flight control modes, aircraft displays, simulator requirements, and approval for IFR test evaluations as well as covering training issues. This new document would complement, not replace documents such as the Airplane Upset Recovery Training Aid.

For over 30 years, field research and laboratory testing has consistently demonstrated that proper utilization of a seat belt dramatically reduces the risk of occupant death or serious injury in motor vehicle crashes. The injury prevention benefits of seat belts require that they remain fastened during collisions. Federal Motor Vehicle Safety Standards and SAE Recommended Practices set forth seat belt requirements to ensure proper buckle performance in accident conditions. Numerous analytical and laboratory studies have investigated buckle inertial release properties. Studies have repeatedly demonstrated that current buckle designs have inertial release thresholds well above those believed to occur in real-world crashes. Nevertheless, inertial release theories persist. Various conceptual amplification theories, coupled with high magnitude accelerations measured on vehicle frame components are used as support for these release theories.

Ford Motor Company is introducing “EcoBoost” gasoline turbocharged direct injection (GTDI) engine technology in the 2010 Lincoln MKS. A logical enhancement of EcoBoost technology is the use of E85 for knock mitigation. The subject of this paper is the optimal use of E85 by using two fuel systems in the same EcoBoost engine: port fuel injection (PFI) of gasoline and direct injection (DI) of E85. Gasoline PFI is used for starting and light-medium load operation, while E85 DI is used only as required during high load operation to avoid knock. Direct injection of E85 (a commercially available blend of ∼85% ethanol and ∼15% gasoline) is extremely effective in suppressing knock, due to ethanol's high inherent octane and its high heat of vaporization, which results in substantial cooling of the charge. As a result, the compression ratio (CR) can be increased and higher boost levels can be used.

The high cost and competitive nature of automotive product development necessitates the search for less expensive and faster methods of predicting vehicle performance. Continual improvements in High Performance Computing (HPC) and new computational schemes allow for the digital evaluation of vehicle comfort parameters including wind noise. Recently, the commercially available Computational Fluid Dynamics (CFD) code PowerFlow, was evaluated for its accuracy in predicting wind noise generated by an external automotive tow mirror. This was accomplished by running simulations of several mirror configurations, choosing the quietest mirror based on the predicted performance, prototyping it, and finally, confirming the prediction with noise measurements taken in an aeroacoustic wind tunnel. Two testing methods, beam-forming and direct noise measurements, were employed to correlate the physical data with itself before correlating with simulation.

This document provides recommended practices for impact testing of ground vehicle that are also aero-capable. The scope characterizes recommended impact testing taking into account the unique design characteristics involved in aero-capable ground vehicle