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The development of an automotive hood for an electric vehicle based on a polymer-metal hybrid configuration is described in this paper. Here, special focus is given only to the engineering design and prototyping phases which are the initial stages of a much bigger project. A project that aims to evaluate the cost efficiency, weight penalty and structural integrity of adopting polydicyclopentadiene as an exterior body material in low production volume vehicles, among them the electric ones. For the engineering design and prototyping phases, three different reinforcement geometries were developed and six mechanical simulations were done through finite element analysis to aid best frame geometry selection and optimization. The entire hood was then prototyped containing the optimized geometry. The fabrication of the frame was made through metal stamping and the exterior panel through reaction injection moulding. Adhesive bonding was used for its assembly.

Connectivity and systems integration together with weight and production cost reduction are among the main objectives of the automotive industry in electric vehicles development in particular, when concerns with smart grids integration and interoperability increases. At the same time vehicle systems reliability plays an important role as a decisive factor for market acceptance. Conventional automotive electrical systems comprehend a central ECU, with radial wiring harness architecture with power and signal cables. A different architecture is proposed with the aim of vehicle cable mass and cost reduction, simplification and increased reliability of the whole electrical control system. With this architecture there's also the aim to provide computing and communications capability to each electric component in a distributed way, in order to enable its integration with external systems like smart phones, networking services and smart grids.

Electric vehicles are seen as a key driver to address the issue of global warming, mainly through their zero tailpipe emissions operation and energy efficiency improvements. However, this does not solve the problem of urban chaos, related to traffic congestion and parking space cluttering, which contribute to increase human stress and overall economic productivity decrease. To address all these issues, electric urban buses come as an obvious solution, and they also have the advantages of being quieter than regular buses and of promoting a better travel experience to passengers. Nowadays there are already electric buses operating in some parts of the world and one of the main concerns is their high weight, which is mainly due to the amount of batteries they carry in order to have an adequate range.

The automotive industry paradigm shift from convention internal combustion engine vehicles to electric vehicles brought new technical challenges for automotive OEMs. During this shifting period, electric vehicles are expected to be produced on small volumes, requiring new design and production processes. In order to have a more flexible and efficient production system, OEMs and suppliers are working on modularity as a design tool to reduce the time to market, reduce the complexity of supply chains and reduce the total vehicle production cost. One of these modular components will be the chassis, which was introduced as a skate by GM on the Sequel concept. On this concept all the crashworthy components were included in the skate, over which an autobody was assembled. This skate-chassis included all the powertrain components, batteries, power electronics and motors, as well as braking and suspension systems.

The increasing trend for electric mobility adoption brings new challenges to the automotive industry, requiring a new approach to the manufacture processes, materials adopted and adaptation the market needs. The conventional technologies used to manufacture automotive parts imply significant overhead costs (tooling, assembly, etc.) which can only be justified by large series. The need of light and cost effective materials was the driving force of this study, acknowledging that the growth of the electric vehicles market will be driven by price. The study aims to deliver a hybrid design material solution that would offer quality and security to the vehicle, affordable to everyone, developing engineered solutions in terms of design and production process. To the study were considered exterior body panels that are conventionally manufactured by sheet metal stamping or conventional thermoplastic injection, both having associated high investment costs related with tooling.

Since the late 19th century until recently several electric vehicles have been designed, manufactured and used throughout the world. Some were just prototypes, others were concept cars, others were just special purpose vehicles and lately, a considerable number of general purpose cars has been produced and commercialized. Since the mid nineties the transportation sector emissions are being increasingly regulated and the dependency on oil and its price fluctuations originated an increasing interest on electric vehicles (EV). A wide research was made on existing electric/hybrid vehicle models. Some of these vehicles were just in the design phase, but most reached the prototype or full market production. They were divided into several types, such as NEVs, prototypes, concept cars, and full homologated production cars. For each type of vehicle model a technical historic analysis was made.

One of the ways to improve thermodynamic efficiency of Spark Ignition engines is by the optimisation of valve timing and lift and compression ratio. The throttleless engine and the Miller cycle engine are proven concepts for efficiency improvements of such engines. This paper reports on an engine with variable valve timing (VVT) and variable compression ratio (VCR) in order to fulfill such an enhancement of efficiency. Engine load is controlled by the valve opening period (enabling throttleless operation and Miller cycle), while the variable compression ratio keeps the efficiency high throughout all speed and load conditions. A computer model is used to simulate such an engine and evaluate its improvement potential, while a single cylinder engine demonstrates these results. The same base engine was run on the test bench under the Diesel cycle, Otto cycle and Miller cycle conditions, enabling direct thermodynamic comparisons under a wide variety of conditions of speed and load.

Spark ignition engines have low efficiency when working at part and light loads. This can be opposed by using a slightly different thermodynamic cycle known as Miller cycle. This cycle can be implemented in conventional engines if they are equipped with systems providing variable valve timing and variable compression ratio. A computer model to simulate internal combustion engines is used to generate and characterize in terms of torque and brake specific fuel consumption, both Otto cycle engines and Miller cycles engines with VCR. These engines are used in a second computer model to generate the European driving cycle, using the same car and the same gear box, in order to evaluate its performance in terms of fuel consumption. Different ratios for gear boxes using the Miller cycle are proposed in order to achieve a more efficient car (engine, gear box, structure), with less fuel consumption and less green house gas emissions for the urban driving operation.

When the exhaust valve of a conventional spark ignition engine opens at the end of the expansion stroke, a large quantity of high pressure exhaust gas is freed to the atmosphere, without using its availability. An engine that could use this lost energy should have a better efficiency. The equations for an over-expanded cycle (Miller cycle) are developed in this paper, together with equations for the Otto cycle, diesel cycle and dual cycle, all at part load, so they can be compared. Furthermore, indicated cycle thermodynamical comparisons of a S.I. engine at part load (Otto cycle at half load), a S.I. engine at WOT (with half displacement) and two over-expanded S.I. engines (with different compression strokes) are examined and compared, with the aim of extending the referred theoretical cycle comparisons.