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This paper summarizes the Fast Fourier Transform (FFT) methodology, special equipment, set-up and testing that is recommended to properly characterize the surface of bearing journals that will not result in objectionable noise or vibration. Traditional surface profiles and finish callouts do not capture some of the key characteristics for addressing what is often the customer's greatest complaint, noise. Noise can vary based on the sensitivity of the vehicle but understanding how to accurately describe (design, test, and measure) a surface for a given vehicle can result in an optimized design and reduce process time during manufacturing. Furthermore, this paper will recommend techniques for determining the proper limits of the FFT callouts.

An ignition delay correlation was developed for a toluene reference fuel (TRF) blend that is representative of automotive gasoline fuels exhibiting two-stage ignition. Ignition delay times for the autoignition of a TRF 91 blend with an antiknock index of 91 were predicted through extensive chemical kinetic modeling in CHEMKIN for a constant volume reactor. The development of the correlation involved determining nonlinear least squares curve fits for these ignition delay predictions corresponding to different inlet pressures and temperatures, a number of fuel-air equivalence ratios, and a range of exhaust gas recirculation (EGR) rates. In addition to NO control, EGR is increasingly being utilized for managing combustion phasing in spark ignition (SI) engines to mitigate knock. Therefore, along with other operating parameters, the effects of EGR on autoignition have been incorporated in the correlation to address the need for predicting ignition delay in SI engines operating with EGR.

The potential impact of real world accident scenarios on fuel cell vehicles equipped with a compressed hydrogen storage system is analyzed from a component point of view. Even though hydrogen compressed gas tanks can sustain very high loads, in this study a simplification is made. It is investigated to what extent different real world accident scenarios with conventional vehicles have caused deformation of the vehicle in the area where a hydrogen tank would have been integrated in a fuel cell vehicle. The study is based on accident data from the GIDAS (German In-Depth Accident Study) database. Deformation matrices for each passenger car in the database are defined over a deformation grid largely independent of vehicle type and shape. The matrices are combined to statistically analyze the occurrence of deformations in selected regions of a vehicle.

The double linear damage model developed by Manson and Halford helps to determine the knee point, which is the intersection between the two straight lines. The damage to the component is then calculated based on this knee point. The new approach mentioned in this paper helps to evaluate the damage on the component in a slightly different way. It uses the knee points as mentioned by Manson and Halford and decomposes the damage to the component for Phase I & Phase II. It then uses the equivalent damage approach and establishes the damage to the component. This will be explained with an example.

The AUTomotive Open System ARchitecture (AUTOSAR) Development Partnership has published early 2008 the specifications Release 3.0 [1], with a prime focus on the overall architecture, basic software, run time environment, communication stacks and methodology. Heavy developments have taken place in the OEM and supplier community to deliver AUTOSAR loaded cars on the streets starting 2008 [2]. The 2008 achievements have been: Improving the specifications in order to secure the exploitation for body, chassis and powertrain applications Adding major features: safety related functionalities, OBD II and Telematics application interfaces.

Advanced High-Strength Steels (AHSS) have become an essential part of the lightweighting strategy for automotive body structures. The ability to fully realize the benefits of AHSS depends upon the ability to aggressively form, trim, and pierce these steels into challenging parts. Tooling wear has been a roadblock to stamping these materials. Traditional die materials and designs have shown significant problems with accelerated wear, galling and die pickup, and premature wear and breakage of pierce punches. [1] This paper identifies and discusses the tribological factors that contribute to the successful stamping of AHSS. This includes minimizing tool wear and galling/die pick-up; identifying the most effective pierce clearance (wear vs. burr height) when piercing AHSS; and determining optimal die material and coating performance for tooling stamping AHSS.

Scuffing is one of the major problems that influence the life cycle and reliability of several auto components, including engine cylinder kits, flywheels, camshafts, crankshafts, and gears. Ferrous casting materials, such as gray cast iron, ductile cast iron and austempered ductile cast iron (ADI) are widely applied in these components due to their self-lubricating characteristics. The purpose of this research is to determine the scuffing behavior of these three types of cast iron materials and compare them with 1050 steel. Rotational ball-on-disc tests were conducted with white mineral oil as the lubricant under variable sliding speeds and loads. The results indicate that the scuffing initiation is due to either crack propagation or plastic deformation. It is found that ADI exhibits the highest scuffing resistance among these materials.

A strong local initiative in Campinas - Brazil is studying how to be more effective in the improvement of road safety in order to align to other worldwide initiatives with similar goals. This paper describes the Brazilian initiative’s approach to the challenge of being aligned with iGLAD (Initiative for the Global Harmonization of Accident Data, starting as a project in 2011 and collecting data since 2007) on the delivery of its first set of accident cases from 2016. The Brazilian source of data started as a pilot project collecting local data with the aim of extending it within the next years to a larger region. In fact, a consistent method for the development of strategies and measures to prevent accidents and mitigate injury severity comes from accident database analysis.

Besides the innovative work in the commercial vehicles sector, where there is an ever growing competition, lighter, more comfortable, safer, and more robust products are also being developed through optimization of design parameters of currently available systems. This study explains the possible effects of changing the design parameters of leaf springs on a vehicle's driving dynamics, which has a significant effect on the total weight of the vehicle. These effects include the vehicle's suspension specifications and the suspension system's interaction with the steering system. A virtual vehicle model is analyzed under the loads gathered in road tests, to measure the stress levels on the spring layers and the movement of the leaf spring depending on the limits determined by the vehicle manufacturer. Furthermore, the conformity of the movement of the front axles in connection with the leaf spring with the steering system is also analyzed.

The development process of a water pump impeller used on a sport utility vehicle engine is described. A review of the design process is presented in this paper including the computer-aided flow analysis together with testing procedures. By computer modeling, one can estimate the coolant flow characteristics of a given impeller blade shape for providing increased cooling performance and improved efficiency on the engine. It also provides directions for the improved design. The test data are used specifically to confirm the analysis results.

In an effort to improve the dent resistance of exterior body panels at reduced steel thicknesses, some automobile manufacturers have pursued the application of bake hardenable steels. Unfortunately, bake hardenable steels have only been available as cold rolled or with electro-zinc or electro zinc/iron coatings. This situation has been a deterrent for those automobile manufacturers that prefer the use of hot dip galvanneal coatings. Recently, the interest in hot dip galvanneal bake hardenable steels has led to the investigation and development of this more advanced steel grade. This paper presents the results of a stamping trial and dent testing on three exposed hot dip galvannealed materials; i) Regular Ultra Low Carbon (ULC), ii) Rephosphorized ULC, and iii) Rephosphorized Bake Hardenable ULC steel.

Today, some vehicles include a regenerative-braking system such as the electrical motor-generator that converts the vehicle's kinetic energy into electrical energy to recharge one or more vehicle batteries. The idea is to use air flow to produce additional electrical energy in response to deceleration of the vehicle. With the Wind Power Generator System (WPGS) as a green system, a vehicle can produce extra energy, reduce gasoline usage, and reduce air pollution.