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Aside from the fuel cell prime mover, the drivetrain elements of a fuel cell hybrid transit bus are those of a heavy-duty series hybrid vehicle. The U.S. National Fuel Cell Bus Program is advancing all aspects of fuel cell transit bus technology, including fuel cells and other electric drivetrain technologies. Key electric drivetrain technologies developed by General Electric (GE) in the Lightweight Battery-dominant Hybrid Fuel Cell Bus project, their integration to the vehicle design, together with the vehicle build and demonstration plans are described. The GE technologies are sodium metal halide energy batteries, the dual battery energy storage system, energy management controls and dc-dc converter power electronics. Further electric drive vehicle technology developments focused on the fuel cell transit bus application are proposed.

Zinc oxide based metal oxide varistors (MOV) are widely used electrical surge protection components. Modern high power, high-density electronics post more requirements such as smaller footprints, higher current density and higher nonlinearity on MOVs. Such requirements can no longer be satisfied by commercially available MOVs due to their limited voltage capability, high leakage current and mechanical cracking related reliability issues, most of which are associated with the presence of non-uniformity, defects and coarse grain in their micro-structures. New formulations and processes have been developed to overcome such limitations. This work has identified compositions that can be sintered at relatively lower temperatures than typical commercial MOVs, but with largely improved I-V characteristics due to refined and uniform microstructure.

This paper discusses the physics of development of electrical defects as the result of wire chafing, and how this can be used to extend the prognostics capability of GE's Smartwire Diagnostic System (SWDS). Chafing, a top symptom of failures (37% in one study [4]) is frequently caused by mechanical vibration of wiring harnesses, which are often strapped to the aircraft structure or run through other types of cable supports (trays, bends, etc.); ambient aircraft structural vibrations are a primary mechanical driver of long term chafing. The US Navy's charter to reduce annual wiring maintenance expenditures by an estimated $57 million provided the driving force for this research effort. No system is available today that can detect and locate a wire insulation chafe without the user disconnecting the wires or passing a high voltage through them. The overall objective of SWDS is to address this gap in wire health monitoring.

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.

This paper describes a methodology to prototype and validate thermoplastic energy absorbers in a broad range of vehicle geometries. The objective of this prototype tool designed with quick prototype methodology is to achieve ready PC/PBT energy absorber designs for pedestrian testing. Generic vehicle models were used to finalize the energy absorber design features. The prototype tool was designed from optimized energy absorber designs that meet pedestrian performance in low packaging space, typically 45–60 mm. A set of prototype tools is being built to match different beam heights and packaging spaces. The tool has also the functionality of achieving different thickness and different design features using the latest manufacturing technologies. A full energy absorber can be built from individual lobes over the width of the car. The finalized design combined with ‘quick prototyping’ methodology was used to finalize the mold design, which can cater to a wide range of vehicle geometries.

With stringent emission norms coming to place for automotive/Off-highway vehicles and locomotives in the next few years, there is a lot of research going on to minimize emission and SFC. For this purpose a lot of areas are explored for significant benefits including the intake and exhaust paths, combustion, after-treatment devices. Of these the intake system, which supplies the cylinder with the required amount of air at required pressure and temperature is one of the critical systems. Various components are modified and added to the intake system to either get the required pressure and temperature (ex: intercoolers and compressor) or to get the required composition (EGR circuit) for emission reduction. Addition or modification of these components increases the pressure loss in the intake system, which affects the airflow rate.

A model has been developed and implemented at GE Plastics that predicts a material's color shift when weathered. The material's color shift is due to the summation of color shifts from each individual component. By individually measuring the change in each component's optical coefficients upon weathering and using a multiple light scattering model, one can predict the color shift of a material composed of mixtures of these components. The model has been shown to have a standard deviation of 0.4 to 0.9 when predicting color shifts E*, for PC-polyester copolymers, ABS, and ABS/PC blends using an automotive exterior test, SAE J1885, ASTM D 4674, and ASTM D 4459.

Current accelerated weathering protocols such as SAE J1960 or ASTM G26 do not provide reliable, predictive results for engineering thermoplastics. Correlation factors among resin types and even different colors of a single resin have variations that are 60-100% of the mean at the 95% confidence level, making these tests useless for lifetime prediction or even reliable ranking of materials. We have developed improved conditions using CIRA/sodalime-filtered xenon arc, a more rain-like water spray, and occasional sponge-wiping of the samples. The data for gloss loss and color shift agree very well with Florida data giving a correlation factor of 3100±680 kJ/m2 (at 340 nm) per Florida year at the 95% confidence level. The acceleration factor is 7.6x.