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A simple strategy for building lightweight automobile body-in-whites (BIWs) is developed and discussed herein. Because cost is a critical factor, expensive advanced materials, such as carbon fiber composites and magnesium, must only be used where they will be most effective. Constitutive laws for mass savings under various loading conditions indicate that these materials afford greater opportunity for mass saving when used in bending, buckling or torsion than in tensile, shear or compression. Consequently, it is recommended that these advanced materials be used in BIW components subject to bending and torsion such as rails, sills, “A-B-C” pillars, etc. Furthermore, BIW components primarily subject to tension, compression, or shear, such as floor pans, roofs, shock towers, etc., should be made from lower cost steel. Recommendations for future research that are consistent with this strategy are included.

The increase of active safety will demand more and more electronic intelligence, if a drastic optimization of conventional systems is not possible any more. Starting from today's mechatronic systems, the trend leads via tomorrow's smart electronic systems to the future electronic networking of all intelligent vehicle systems. The paper describes the present status of these systems in Europe and the possibilities of increasing the active safety by using electronic intelligence.

The 45RFE is a new generation electronically controlled rear wheel drive automatic transmission. It employs real-time feedback, closed-loop modulation of shift functions to achieve outstanding shift quality and to meet demanding durability goals. It uses no shift valves; all friction element applications are effected with high-flow electro-hydraulic solenoid valves. A unique gear train arrangement of three planetary carriers allows all sun gears and annulus gears to have the same number of teeth respectively and use a common pinion gear in all carriers, resulting in significant manufacturing simplification. The three-planetary system is designed for four forward ratios of 3.00, 1.67, 1.00 and 0.75 and one reverse gear ratio equal to the low gear ratio. A fifth ratio of 1.50 is used only in certain kick-down shift sequences for highway passing. A sixth forward ratio, an additional overdrive ratio of 0.67, is available in the hardware.

The U.S. Environmental Protection Agency, U.S. Department of Transportation's National Highway and Traffic Safety Administration, and the California Air Resources Board have recently released proposed new regulations for greenhouse gas emissions and fuel economy for light-duty vehicles and trucks in model years 2017-2025. These proposed regulations intend to significantly reduce greenhouse gas emissions and increase fleet fuel economy from current levels. At the fleet level, these rules the proposed regulations represent a 50% reduction in greenhouse gas emissions by new vehicles in 2025 compared to current fleet levels. At the same time, global growth, especially in developing economies, should continue to drive demand for crude oil and may lead to further fuel price increases. Both of these trends will therefore require light duty vehicles (LDV) to significantly improve their greenhouse gas emissions over the next 5-15 years to meet regulatory requirements and customer demand.

Developing an effective side impact ATD for assessing vehicle impact responses requires a method for evaluating that ATD's bio-fidelity. ISO/TR9790 has been in existence for some years to serve that purpose. Recently, NHTSA sponsored a research project on the post-mortem human subjects (PMHS) responses subjected to side impact conditions. Based on those newly available PMHS data, Maltese generated a new approach for creating bio-fidelity corridors for human surrogates. The approach incorporates the time factor into the evaluation equation and automates the process (Maltese et al. 2002). This paper serves as the first attempt to look closely at the new bio-fidelity corridor generation process (hereafter referred as the Maltese approach) with respect to its validity, effectiveness, as well as its practicality. The effect of mass scaling was first examined in order to ensure the integrity of the data. The time alignment scheme and the formation of the corridors were then tested.

New supplier / manufacturer relationship are necessary to produce products quickly, cost-effectively, and with features expected by the customer. However, the need for a new relationship is not universally accepted and endorsed. Resistance can be minimized through supplier self-assessment (such as Ford Motor Company's web-based instruments), management initiatives, and incentives. Trust and sharing are hallmarks. This strategy requires a new workplace paradigm affecting culture and people issues. Teams, extend across companies, share ideas and innovations. Decisions need to be mutually beneficial and the long-term value, for supplier and manufacturer, needs to be considered.

This paper dis cusses the development of a nonlinear shock absorber model for low-frequency CAE-NVH applications of body-on-frame vehicles. In CAE simulations, the shock absorber is represented by a linear damper model and is found to be inadequate in capturing the dynamics of shock absorbers. In particular, this model neither captures nonlinear behavior of shock absorbers nor distinguishes between compression and rebound motions of the suspension. Such an inadequacy limits the utility of CAE simulations in understanding the influence of shock absorbers on shake performance of body-on-frame vehicles in the low frequency range where shock absorbers play a significant role. Given this background, it becomes imperative to develop a shock absorber model that is not only sophisticated to describe shock absorber dynamics adequately but also simple enough to implement in full-vehicle simulations. This investigation addresses just that.

The Ethanol-Boosted Direct Injection (EBDI) demonstrator engine is a collaborative project led by Ricardo targeted at reducing the fuel consumption of a spark-ignited engine. This paper describes the design challenges to upgrade an existing engine architecture and the synergistic use of a combination of technologies that allows a significant reduction in fuel consumption and CO₂ emissions. Features include an extremely reduced displacement for the target vehicle, 180 bar cylinder pressure capability, cooled exhaust gas recirculation, advanced boosting concepts and direct injection. Precise harmonization of these individual technologies and control algorithms provide optimized operation on gasoline of varying octane and ethanol content.

For the purposes of analyzing and understanding the general effects of a set of different vehicle attributes on overall crash outcome a fleet model is used. It represents the impact response, in a one-dimensional sense, of two vehicle frontal crashes, across the frontal crash velocity spectrum. The parameters studied are vehicle mass, stiffness, intrusion, pulse shape and seatbelt usage. The vehicle impact response parameters are obtained from the NCAP tests. The fatality risk characterization, as a function of the seatbelt use and vehicle velocity, is obtained from the NASS database. The fatality risk is further mapped into average acceleration to allow for evaluation of the different vehicle impact response parameters. The results indicate that the effects of all the parameters are interconnected and none of them is independent. For example, the effect of vehicle mass on fatality risk depends on seatbelt use, vehicle stiffness, available crush, intrusion and pulse shape.

Heavy trucks are produced with a great variety of vehicle configurations, operate over a wide range of gross vehicle weight and sometimes function in extreme duty environments. Frontal crashes of heavy trucks can pose a threat to truck occupants when the vehicle strikes another large object such as bridge works, large natural features or another heavy-duty vehicle. Investigations of heavy truck frontal crashes indicate that the factors listed above all affect the outcome for the driver and the resulting damage to the truck Recently, a new chassis was introduced for on-highway heavy truck models that feature frontal airbag occupant protection. This introduction presented an opportunity to incorporate the knowledge gained from crash investigation into the process for developing the crash sensor's parameter settings.

A new multi-layer co-extruded in-color Ionomer film is developed to provide an alternative decoration process to replace paint on Dodge Neon Fascias. The Ionomer film provides a high-gloss “class-A” surface in both non-metallic and metallic colors that match the car body paint finish. Using the Ionomer film to decorate fascias reduces cost; eliminates VOCs; increases manufacturing flexibility and improves performance (weatherability and durability). The molding process consists of thermoforming a film blank and injection molding Polypropylene or TPO behind the film. The paper will include the background, the benefits, the technology development objectives, the film materials development, tooling optimization, film fascia processing (co-extrusion; thermoforming and injection molding) and validation testing of the film.

The development of electronic intelligence and the continually increasing intensive knowledge of driving dynamics make it possible nowadays to conceive intelligent vehicle systems and to make such systems available for series production, which are capable of substantially enhancing the active safety of commercial vehicles. Through the implementation of advanced subsystems, which can be integrated as software packages into the basic electronic braking system, it will be possible to expand the possibilities of introducing assistance systems, which are capable of both, helping and relieving the driver from stress in critical situations. The driver will be relieved of all duties which could divert his attention or cause severe stress. As a consequence, the active safety of commercial vehicles will be considerably increased.

It is often necessary to dynamically test a big vehicle part such as a rail tip at component level in high speed. Such a big part can be crush tested dynamically using two sled carriers. The methodology is shown and discussed here, and equations are developed to help determine required parameters such as sled velocity and weights. Test results using a truck rail tip are shown and compared to full vehicle test results for correlation.

Truck frame structural performance of body on frame vehicles is greatly affected by crossmember and joint design. While the structural characteristics of these joints vary widely, there is no known tool currently in use that quickly predicts joint stiffness early in the design cycle. This paper will describe a process used to evaluate the structural stiffness of frame joints based on research of existing procedures and implementation of newly developed methods. Results of five different joint tests selected from current production body-on-frame vehicles will be reported. Correlation between finite element analysis and test results will be shown. Three samples of each joint were tested and the sample variation will be shown. After physical and analytical testing was completed, a Design of Experiments approach was implemented to evaluate the sensitivity of joints with respect to gauge and shape modification.

This paper describes a lightweight magnesium intensive automobile body structure concept developed at DaimlerChrysler to support a high fuel-efficiency vehicle project. This body structure resulted in more than 40% weight reduction over a conventional steel structure while achieving significantly improved structural performance as evaluated through CAE simulations. A business case analysis was conducted and showed promising results. One concept vehicle was built for the purpose of demonstrating concept feasibility. The paper also identifies areas for further development to enable such a vehicle to become a production reality at a later time.

Different methodologies to test and analyze the dynamic stiffness (K) and damping (C) properties of several silicone and EPDM rubber automotive exhaust hangers were investigated in this research. One test method utilized a standard MTS hydraulic test machine with a single sine excitation at discrete frequencies and amplitude levels, while a second method utilized an electrodynamic shaker with broadband excitation. Analysis techniques for extracting the equivalent stiffness and damping were developed in the shaker tests using data from time domain, frequency domain, as well as force transmissibility. A comparison of all of the shaker testing methods for repeatability and accuracy was done with the goal of determining the appropriate method that generates the most consistent results over the range of testing. The shaker testing in the frequency domain using a frequency response function model produced good results and the set-up is relatively inexpensive.

Horizontal and vertical axle and cabin dampers are used on cars, trucks and busses to optimize the ride and safety and therefore represent vital components of the truck suspension. Nowadays there is a trend in industry for a longer component life featured by a shorter-term design. Therefore it becomes less obvious to have too many iterations in design with successive (long) durability test drives. Using the presented methodology the potential life damage for each critical component is identified from realistic road measurements and a life test is proposed which causes the same damage but in a relatively shorter period. This methodology was drawn up and validated during a European research program, Fatynamics.

During the design process for a vehicle, the CAD surface geometry becomes available at an early stage so that numerical assessment of aerodynamic performance may accompany the design of the vehicle's shape. Accurate prediction requires open grille models with detailed underhood and underbody geometry with a high level of detail on the upper body surface, such as moldings, trim and parting lines. These details are also needed for aeroacoustics simulations to compute wall-pressure fluctuations, and for thermal management simulations to compute underhood cooling, surface temperatures and heat exchanger effectiveness. This paper presents the results of a significant effort to capitalize on the investment required to build a detailed virtual model of a pickup truck in order to simultaneously assess performance factors for aerodynamics, aeroacoustics and thermal management.

In response to environmental and fossil fuel usage concerns, the automotive industry will gradually move from Hybrid Electric Vehicles (HEV) which includes a shift of internal combustion engines toward Zero Emissions Vehicles (ZEV). Refinement is an important aspect in the successful adoption of any new technology and ZEV brings its own NVH challenges owing to the unique dynamic characteristics of the powertrain and driveline system. This paper presents considerations for addressing dynamic driveline NVH issues that are common to 100% electric vehicles; issues that manifest themselves as groans, rattles and clunks. A dynamic torsional analytical model of the powertrain & driveline will be presented. The analytical model served as the baseline for an extensive parametric study using the Genetic Algorithm (GA) technique, whereby the effectiveness of practical countermeasures was investigated.

In automotive industry, all passenger vehicles are treated with damping materials to reduce structure borne noise. The effectiveness of damping treatments depends upon design parameters such as choice of damping materials, locations and size of the treatment. This paper proposes a CAE (Computer Aided Engineering) methodology based on finite element analysis to optimize damping treatments. The developed method uses modal strain-energy information of bare structural panels to identify flexible regions, which in turn facilitates optimization of damping treatments with respect to location and size. The efficacy of the method is demonstrated by optimizing damping treatment for a full-size pick-up truck. Moreover, simulated road noise performances of the truck with and without damping treatments are compared, which show the benefits of applying damping treatment.