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Owing to their weight saving potential and improved flexural stiffness, metal-polymer-metal sandwich laminates are finding increasing applications in recent years. Increased use of such laminates for automotive body panels and structures requires not only a better understanding of their mechanical behavior, but also their formability characteristics. This study focuses on the formability of a metal–polymer-metal sandwich laminate that consists of AA5182 aluminum alloy as the outer skin layers and polypropylene (PP) as the inner core. The forming limit curves of Al/PP/Al sandwich laminates are determined using finite element simulations of Nakazima test specimens. The numerical model is validated by comparing the simulated results with published experimental results. Strain paths for different specimen widths are recorded.

Tubular sections are found in many automotive structural components such as front rails, cross beams, and sub-frames. They are also used in other vehicular structures, such as buses and rails. In many of these components, smaller tubular sections may be joined together using an adhesive to build the required structure. For crash safety applications, it is important that the joined tube sections be able to provide high energy absorption capability and withstand the impact load before the adhesive bond failure occurs. In this study, single lap tubular joints between two aluminum tubes are investigated for their crush performance at both quasi-static and high impact speeds using finite element analysis. A crash optimized adhesive Betamate 1496 is considered. The joint parameters, such as adhesive overlap length, tube diameters and tube lengths, are varied to determine their effects on energy absorption, peak and mean loads, and tube deformation mode.

In frontal collision of vehicles, the front bumper system is the first structural member that receives the energy of collision. In low speed impacts, the bumper beam and the crush cans that support the bumper beam are designed to protect the engine and the radiator from being damaged, while at high speed impacts, they are required to transfer the energy of impact as uniformly as possible to the front rails that contributes to the occupant protection. The bumper beam material today is mostly steels and aluminum alloys, but carbon fiber composites have the potential to reduce the bumper weight significantly. In this study, crash performance of bumper beams made of a boron steel, aluminum alloy 5182 and a carbon fiber composite with steel crush cans is examined for their maximum deflection, load transfer to crush cans, total energy absorption and failure modes using finite element analysis.

This paper presents results of two surveys, namely, a photographic measurements survey and a rider survey, conducted to determine how the type and origin of a motorcycle related to motorcycle dimensions, rider characteristics, seating posture, and motorcycle controls and displays. In the photographic survey, 12 most popular motorcycles covering three types (cruiser, sport, and touring) and three origins (Europe, Asia and North America) were measured from photographs taken in a standardized procedure with and without a rider. The data showed that the Asian and North American cruisers were very similar in all dimensions. These include seat height, seat to handlebar location, seat to foot rest location, foot rest size, and handgrip stance. This resulted in similar rider posture. North American sport motorcycles were more like cruisers than the Asian and European sport motorcycles.

This paper presents results of a five phase study conducted to evaluate touch feel and appearance of door armrest materials. Seven different production door armrests with different material characteristics such as softness, smoothness, compressibility, texture, etc. were evaluated. In the first phase, the subjects seated in a vehicle buck in their preferred seating position with the armrests adjusted at their preferred heights, provided ratings on a number of touch feel and appearance of the door armrest materials using 5-point semantic differential scales. In the second phase, the armrests were presented to each subject in all possible pairs and they were asked to select preferred armrest material in each pair.

This paper describes a research project currently in-progress to develop a parametric model of a vehicle for use in early design stages of a new vehicle program. The model requires key input parameters to define the kind of new vehicle to be designed — in terms of details such as its intended driver/user population, vehicle type (e.g. 2-box, 3-box designs), and some key exterior and interior dimensions related to its size and proportions. The model computes and graphically displays interior package, ergonomics zones for driver controls and displays, and field of views through window openings. It also allows importing or inputting and superimposing and manipulating exterior surfaces created by a designer to assess compatibility between the interior occupant package and the vehicle exterior.

This paper describes a unique interior design and multidisciplinary process implemented by the faculty and students to develop the interior for a Low Mass Vehicle (LMV). The 103 inch LMV was designed with the goal of about 30% reduction in weight than a typical class C segment vehicle and would require low investment in manufacturing. In the early stages of the program, the UM-Dearborn team developed detailed requirements of the vehicle interior based on the vehicle's exterior developed using a similar process. The requirements were given to a senior class of automotive design students from the College of Creative Studies in Detroit to create different interior design themes. Approximately twenty-five interior design themes were judged by a panel of automotive industry experts, and a winning design was selected.

Based on the theory of damage mechanics, an orthotropic damage model for the prediction of forming limit diagram (FLD) is developed. The conventional method of FLD used to predict localized necking adopts two fundamentally different approaches. Under biaxial loading, the Hill's plasticity method is often chosen when α (= ε2/ε1) < 0. On the other hand, the M-K method is adopted for the prediction of localized necking when α > 0 or the biaxial stretching of sheet metal is pronounced. The M-K method however suffers from the arbitrary selection of the imperfection size, thus resulting in inconsistent predictions. The orthotropic damage model developed for predicting the FLD is based on the anisotropic damage model recently proposed by Chow et al (1993). The model is extended to take into account, during the sheet forming process, orthotropic plasticity and damage. The orthotropic FLD model consists of the constitutive equations of elasticity and plasticity coupled with damage.