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This paper presents a novel approach to design an efficient energy absorber using thermoplastic (PC/PBT - Polycarbonate/ Polybutylene Terephthalate) material. Automotive industry always demands minimum package space between bumper beam and fascia from styling perspective. This requires an efficient energy absorber, which can meet the energy absorption target through an idealized force-intrusion performance. In the present study, thermoplastic energy absorber with sequential failure is designed through geometrical configuration to achieve the idealized Force-Deformation (FD) curve. CAE techniques are used extensively for optimizing the design parameters of energy absorber to achieve the desired performance level. The results in the form of FD curve are compared with the idealized curve and the efficiency is calculated. Comparative studies are also performed with foam energy absorber solution.

Demand for optimum brightness, better visibility, and lower power consumption for illuminating automotive instrument panels and displays has been steadily increasing. Printed clear or matte plastic films have been used to provide necessary local diffusion of light to hide the lamps and structural details behind the display, while transmitting light where illumination is needed. Such films may be limited in meeting the necessary functionality, without additional lighting and surface treatments to reach adequate brightness and contrast levels. Recent developments of advanced display films for the LCD TV and Monitor markets enabled the extension of certain light management capabilities of such films to the automotive displays and instrument panels. This paper addresses the introduction of polycarbonate (PC) films comprising engineered surface features for improved contrast and brightness.

Automotive OEMs are proactively working on vehicle light-weighting, powertrain optimization, alternate/renewable energy sources and combinations of the three to meet challenging corporate average fuel economy (CAFE) standards. Light-weighting of the body-in-white (BIW) is an obvious choice for vehicle light-weighting as this structure contributes to more than 30-35% of the total weight of a car. Changing manufacturing and assembly lines requires substantial investment. As such, OEMs are exploring short-term light-weighting strategies that do not require any major changes to the BIW. Local reinforcement for the BIW are pertinent solutions that does not require any major changes in the existing assembly lines. This paper focuses on the development of BIW reinforcement solutions using engineering thermoplastic materials that can be mounted at appropriate locations on a vehicle’s BIW to achieve significant weight savings without compromising crash performance.

Automobile manufacturers, designers, and cockpit system integrators are in constant search of solutions that reduce the number of interruptions across interior surfaces. Engineers require that this solution be efficient in terms of reliability, parts complexity, packaging space, and cost. The purpose of this paper is to describe the design and development of a cost effective, simplified seamless passenger airbag door system with an integrated chute for instrument panels. Through engineering thermoplastic material property advantages and scoring designs, this solution has a construction which may meet both styling and performance criteria while eliminating component parts such as a separate airbag chute, hinges, tethers, brackets, inserts, fabrics, and fasteners.

Worldwide involvement in Global Technical Regulation (GTR) discussion shows the increasing importance of pedestrian safety as a global concern. Vehicle front styling plays an important role in vehicle to pedestrian impact. Front styling can change the pedestrian kinematics and injury levels during an impact. Key elements of bumper front are Fascia, Upper & Lower Grille, Hood, spoiler or undertray, bumper beam and height of these components from ground level, determine the vehicle aggressiveness for pedestrian safety. This paper presents an approach to diagnose the vehicle front aggressiveness for pedestrian leg impact. Eight different vehicle bumper front configurations from ‘minis’ to ‘sedans’ are studied for lower leg impact cases, to understand the bumper stiffness profile (stiffness in upper, middle and lower load path).

Previous papers by the present authors described use of computational fluid dynamics (CFD) to quantify the effect of glazing thermal conductivity on steady-state heating, ventilation and air-conditioning (HVAC) load under wide-ranging climate and state of motion scenarios, and to estimate the significance of this effect for electric battery performance. The CFD simulations yielded the total heat transfer between the ambient and the cabin of a model car, including radiative and convective heat transfer. The five-fold lower inherent thermal conductivity of polycarbonate relative to glass was found to reduce steady-state HVAC load by several percent in all scenarios, leading to reduced greenhouse gas emission or increased electric range, according to the type of vehicle.

Improving passenger car damageability has been an important topic for The Insurance Institute for Highway Safety (IIHS) and the Research Council for Automotive Repairs (RCAR) council. Incorporation of new IIHS/RCAR barrier (Rigid bumper shaped barrier fitted with an energy absorbing material and cover) in ‘Bumper Structural Test protocols’ closely replicates the damage patterns observed in real world low-speed crashes. Inclusion of new IIHS/RCAR barrier impact (10kmph speed) test, along with IIHS and RCAR bumper test protocols, redefines the development of countermeasures for low speed damageability. In this paper an innovative cost effective, and lightweight, hybrid bumper beam solution is proposed with thermoplastics and steel, to meet IIHS and RCAR impact requirements including new IIHS/RCAR barrier impact test protocols.

Global warming and climate change are among the top subjects of growing global concern. According to International Energy Agency (IEA), about 19% of the greenhouse gas emissions from fuel combustion are generated by the transportation sector, and its share is likely to grow. A forecast by US Census Bureau predicts that there will be 3.5 billion cars by 2050 for a population of 9 billion. In this context, numbers in the industrialized world are expected to double from around half a billion to over one billion. An increase in fleet volume will have a direct and major impact on increase of CO₂ emissions. Therefore, reducing vehicle fuel consumption is one of the most critical steps for reducing greenhouse gas emissions, and reduction of vehicle weight is one of the best solutions for improving fuel efficiency.

The worldwide involvement in global technical regulation (GTR) discussion shows the increasing importance of pedestrian safety as a global concern. In the US, bumper systems are designed for the Part 581 bumper standard and IIHS (Insurance Institute of Highway Safety) bumper structural test protocols. There has also been discussion in the North American automotive industry about the merits of incorporating some measure of pedestrian protection into their systems as well. Compliance with the potential pedestrian leg requirements creates a design conflict with current bumper damageability standards and possibly CAFÉ laws. The difficulties of designing a bumper system that is rigid enough to protect the vehicle in low speed crashes and, at the same time, compliant enough to protect a pedestrian raise questions as to whether these ideas are compatible.

As the pedestrian impact regulations are continuing to evolve, there is a growing emphasis on each and every component of a vehicle front to be pedestrian friendly. Traditionally pedestrian safety during an automotive impact is ensured through bumper, grill, fender and hood. However, the headlamp design was not under the same level of consideration as compared to other frontal components. To make pedestrian safety complete, the headlamp also needs to adhere to the pedestrian safety regulations. A novel energy absorber ring (EAR) concept was developed to make the headlamps pedestrian friendly. The proposed EAR concept was found to improve the pedestrian safety and low speed vehicle damageability performance. It was also observed that the proposed concept reduces the replacement and insurance cost.

Automotive steering wheel (SW) is generally manufactured with metal armature and polyurethane / polypropylene (PU / PP) overmolding. The metal armature is used to provide structural stiffness and strength while PU / PP foam gives shape, touch and feel. Developed market use cast Magnesium or Aluminum as armature material, however emerging markets use steel for armature construction. With additional requirements (airbag integration, functional integration, aesthetics, compact and light weigh) being added to steering wheel, the steering wheel design is becoming more and more complex in nature. Thermoplastic SW offers competitive stiffness, impact, ductility and chemical resistance characteristics needed for the global automotive markets. A thermoplastic SW had been developed from a unique recyclable polycarbonate.

This paper presents a Finite element analysis (FEA) methodology to predict the behavior of an automotive thermoplastic fender subjected to the e-coat paint bake cycle. Such a methodology, essential for an optimum fender design involves solution of a thermo-viscoelastic problem whose solution is not yet reported in literature. This FEA methodology employed in the early design phase would help in the development of an optimum thermoplastic fender and support strategy. It is shown with help of a case study that the efficacy of different support combinations and their effect on final fender deformations can be predicted virtually very early in the design phase. While this paper presents the methodology and its application using the example of a large body panel (BP) like fender, it can easily be applied for predicting the response of other thermoplastic parts like tailgate and tank flap during the paint cycle.

This paper is motivated by the need to predict deformation behavior of an automotive thermoplastic fender during its residence in e-coat paint bake oven where it is heated by convective currents from blowers. Part - 1 [ 1 ] of this paper, presented a FEA methodology to model the behavior of thermoplastic fender during ecoat bake. Additionally a multiphysics computational procedure to include effect of temperature and stress history was also proposed to enhance the accuracy of the solution. In this paper, we focus on the prediction of temperature history and its influence on fender deformation. Towards this, we present a two-stage thermo-mechanical simulation procedure utilizing CFD and FEA to model the ecoat bake process. While the procedure can model the heating of the fender by convective currents from blowers using CFD, the required flow field data of the ecoat oven is highly confidential.

High repair cost and the subsequent increase in insurance cost in a highly competitive automobile market have forced every automobile original equipment manufacturer (OEM) to comply with the FMVSS and ECE-42 regulatory requirements of low-speed vehicle damageability. Although, the terminologies used are different, similar regulatory requirements also exist in Asia-pacific region. At the rear side, reducing the damage to expensive vehicle components in a low-speed pendulum impact or a low-speed barrier impact can attain a good rating for low-speed vehicle damageability. This paper focuses on a detailed study of various lightweight plastic rear beam designs and their effectiveness in reducing the damage to the vehicle during low-speed vehicle-to-vehicle collision or vehicle to barrier collision.

A headlamp reflector has many performance requirements. Principal among these is the need to deliver a compliant beam pattern while withstanding a severe heat environment. In serving this requirement, the reflector must reliably secure the light source (bulb filament) relative to the optical prescription (facets) of the reflector. Traditionally, achieving this performance requirement has been challenging since the reflector elements which are designed to deliver stable and reliable optical performance, are the same elements which must also withstand thermal stresses and adjustment-related static stresses within the reflector. The integrity of these optical elements may also be limited by surface sink, especially in the bulb fastening and attachment locations. The current work describes the design of a reflector bracket through which these forces can be minimized and accommodated while delivering robust optical performance.

An automobile is designed to meet numerous impact events, including frontal impact, side impact, rear impact, and roll over. Roof crush resistance is a test defined by Federal Motor Vehicle Safety Standard (FMVSS) 216. The intent of this test is to evaluate the strength of the roof and supporting body structure during a vehicle rollover. Steel countermeasures are typically used as structural-reinforcing elements to the body structure to improve the crush strength of a vehicle roof. This paper presents a thermoplastic countermeasure (CM) design as a light-weight solution to replace traditional steel countermeasures. Two concepts are discussed in the paper: an all-plastic countermeasure and a plastic/metal hybrid countermeasure consisting of stamped steel with a thermoplastic reinforcing rib structure. Finite Element (FE) methods using LS-DYNA are used to evaluate the performance of these countermeasure concepts.