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This paper attempts to integrate a derivative-free probability analysis method to Reliability-Based Robust Design Optimization (RBRDO). The Eigenvector Dimension Reduction (EDR) method is used for the probability analysis method. It has been demonstrated that the EDR method is more accurate and efficient than the Second-Order Reliability Method (SORM) for reliability and quality assessment. Moreover, it can simultaneously evaluate both reliability and quality without any extra expense. Two practical engineering problems (vehicle side impact and layered bonding plates) are used to demonstrate the effectiveness of the EDR method.

In the last decade, considerable advances have been made in reliability-based design optimization (RBDO). One assumption in RBDO is that the complete information of input uncertainties are known. However, this assumption is not valid in practical engineering applications, due to the lack of sufficient data. In practical engineering design, information concerning uncertainty parameters is usually in the form of finite samples. Existing methods in uncertainty based design optimization cannot handle design problems involving epistemic uncertainty with a shortage of information. Recently, a novel method referred to as Bayesian Reliability-Based Design Optimization (BRBDO) was proposed to properly handle design problems when engaging both epistemic and aleatory uncertainties [1]. However, when a design problem involves a large number of epistemic variables, the computation task for BRBDO becomes extremely expensive.

This paper presents an innovative approach for quality engineering using the Eigenvector Dimension Reduction (EDR) Method. Currently industry relies heavily upon the use of the Taguchi method and Signal to Noise (S/N) ratios as quality indices. However, some disadvantages of the Taguchi method exist such as, its reliance upon samples occurring at specified levels, results to be valid at only the current design point, and its expensiveness to maintain a certain level of confidence. Recently, it has been shown that the EDR method can accurately provide an analysis of variance, similar to that of the Taguchi method, but is not hindered by the aforementioned drawbacks of the Taguchi method. This is evident because the EDR method is based upon fundamental statistics, where the statistical information for each design parameter is used to estimate the uncertainty propagation through engineering systems.

In recent years, Nearfield Acoustical Holography (NAH) has been used to identify stationary vehicle exterior noise sources. However that application has usually been limited to individual components. Since powertrain noise sources are hidden within the engine compartment, it is difficult to use NAH to identify those sources and the associated partial field that combine to create the complete exterior noise field of a motor vehicle. Integrated Nearfield Acoustical Holography (INAH) has been developed to address these concerns: it is described here. The procedure entails sensing the sources inside the engine compartment by using an array of reference microphones, and then calculating the associated partial radiation fields by using NAH. In the second part of this paper, the use of farfield arrays is considered. Several array techniques have previously been applied to identify noise sources on moving vehicles.

China has become the world’s largest vehicle market in terms of sales volume. Automobiles sales keep growing in recent years despite the declining economic growth rate. Due to the increasing attention given to the environmental impact, more stringent emission regulations are being drafted to control traditional internal combustion engine emissions. In order to reduce vehicle emissions, environmentally-friendly new-energy vehicles, such as electric vehicles and plug-in hybrid vehicles, are being promoted by government policies. The Chinese government plans to boost sales of new-energy cars to account for about five percent of China’s total vehicle sales. It is well known that more electric and electronic components will be integrated into a vehicle platform during vehicle electrification.

This study investigates occupant containment characteristics of tempered and laminated automotive moveable side glass in rollover collisions. FMVSS 216 test protocols were used to induce roof damage or sheet metal damage around the window opening in Lincoln Navigators equipped with tempered and laminated side glass. Dummy-drop tests were then performed to investigate relative containment. The results demonstrate that, for rollovers in which the window structure is compromised, tempered side glass and laminated side glass perform comparably relative to occupant containment. Also discussed are the general strength characteristics of different types of glass construction, the availability of laminated side glass in recent model U.S. vehicles, and anecdotal data supporting the conclusions of testing.

This paper describes the heat transfer model of a composite aluminum brake rotor and compares the predicted temperatures to dynamometer measurements taken during a 15 fade stop trial. The model is based on meshed surface geometry which is simulated using RadTherm software. Methods for realistically modeling heat load distribution, surface rotation, convection cooling and radiation losses are also discussed. A comparison of the simulation results to the dynamometer data shows very close agreement throughout the fade stop trial. As such, the model is considered valid and will be used for further Steel Clad Aluminum (SCA) rotor development.

The growth of auto sales in emerging markets provides a good opportunity for automakers. Cost is a key factor for any automaker to win in an emerging market. This paper analyzes risks and opportunities in a low cost manufacturing environment. The Chinese auto market is used as an example and three categories of risks are analyzed. A typical risk assessment for cost reduction includes the analysis of environment risks, process risks and strategic risks associated with all phases of a product life. In an emerging market, emission regulations are a rapidly-evolving environment variable, since most countries with less regulated emission codes try to catch up with the newly- developed technologies to meet sustainable growth targets. Emission regulations have a huge impact on product design, manufacturing and maintenance in the automotive industry, and hence the related cost reduction must be thoroughly analyzed during risk assessment.

This paper provides a review of the fatigue properties reported in the open literature for die cast magnesium-based alloys. Recently developed fatigue data, in the form of stress versus number of cycles to failure for bending fatigue (R=-1), are presented for die cast AM60B and AZ91D alloy specimens with thicknesses between 1 and 10 mm. The effects of specimen thickness and macrostructural features, such as porosity distributions and surface features (parting line and ejection pin marks), on the fatigue data are discussed.

Hydraulic fluids of the HFC category are aqueous polymer solutions with a fire resistance enhancing water content of 35 to approx. 50 %. The use of HFC fluids, above all in mobile and stationary drives in mining and in casting is subject to restrictions resulting from a number of features of a fluid. Field practice has shown that while axial-piston pumps may be successfully operated using HFC fluids, rolling bearing failures reduce their operational lifetimes. The bearing failures essentially result from material fatigue. This can be remedied by new quality steel for roller bearings. The combination of high fatigue life and corrosion resistance assures a wide application range for nitrogen-treated steel qualities.

Several of the authors have recently developed procedures to efficiently evaluate experimentally the relative contributions of various wind noise paths and sources. These procedures are described and, as a case study, results are provided for the noise in the interior of a production automobile subjected to wind tunnel airflow. The present measurements and analysis indicate that for the tested vehicle significant contributions to interior noise are provided by underbody and wheel well flows, radiation from the roof and seal aspiration. A significant tone associated with vortex shedding from the radio antenna was also noted.

The introduction of a thin fluid layer between two layers of sheet metal offers a highly effective and economical alternative to the use of constrained viscoelastic damping layers in sheet metal structures. A diesel engine gear cover, which is constructed of two sheet metal sections spot welded together, takes advantage of fluid layer damping to produce superior vibration and sound radiation performance. In this paper, the bending of a double layered plate coupled through a thin fluid layer is modeled using a traveling wave approach which results in a impedance function that can be used to assess the vibration and sound radiation performance of practical double layered plate structures. Guided by this model, the influence of fluid layer thickness and inside-to-outside sheet thickness is studied.

To reduce the number and severity of accidents, automakers have invested in active safety systems to detect and track neighboring vehicles to prevent accidents. These systems often employ RADAR and LIDAR, which are not degraded by low lighting conditions. In this research effort, reflections from deer were measured using two sensors often employed in automotive active safety systems. Based on a total estimate of one million deer-vehicle collisions per year in the United States, the estimated cost is calculated to be $8,388,000,000 [1]. The majority of crashes occurs at dawn and dusk in the Fall and Spring [2]. The data includes tens of thousands of RADAR and LIDAR measurements of white-tail deer. The RADAR operates from 76.2 to 76.8 GHz. The LIDAR is a time-of-flight device operating at 905 nm. The measurements capture the deer in many aspects: standing alone, feeding, walking, running, does with fawns, deer grooming each other and gathered in large groups.

Relative velocity detection thresholds of drivers are one factor that determines their ability to avoid rear-end crashes. Laboratory, simulator and driving studies show that drivers could scale relative velocity when it exceeded the threshold of about 0.003 rad/sec. Studies using accident reconstruction have suggested that the threshold may be about ten times larger. This paper discusses this divergence and suggests reasons for it and concludes that the lower value should be used as a true measure of the psychological threshold for detection of relative velocity.

Surrogate targets are used throughout the automotive industry to safely and repeatably test Advanced Driver Assistance Systems (ADAS) and will likely find similar applications in tests of Automated Driving Systems. For those test results to be applicable to real-world scenarios, the surrogate targets must be representative of the real-world objects that they emulate. Early target development efforts were generally divided into those that relied on sophisticated radar measurement facilities and those that relied on ad-hoc measurements using automotive grade equipment. This situation made communication and interpretation of results between research groups, target developers and target users difficult. SAE J3122, “Test Target Correlation - Radar Characteristics”, was developed by the SAE Active Safety Systems Standards Committee to address this and other challenges associated with target development and use. J3122 addresses four topics.

2013 and 2014 Ford Flex vehicles and airbag control modules with event data recorders (EDRs) were tested to determine the accuracy of speed and other data in the steady state condition, to evaluate time reporting delays under dynamic braking conditions, and to evaluate the accuracy of the stability control system data that the module records. This recorder is from the Autoliv RC6 family and this is the first known external research conducted on post 49CFR Part 563 Ford EDRs. The vehicle was instrumented with a VBox and a CAN data logger to compare external GPS based speeds to CAN data using the same synchronized time base. The vehicle was driven in steady state, hard braking, figure 8 and yaw conditions. The Airbag Control Module (ACM) was mounted onto a moving linear sled. The CAN bus data from driving was replayed as the sled created recordable events and the EDR data was compared to the reference instrumentation.