No description available.

No description available.

No description available.

No description available.

No description available.

No description available.

The Hybrid Electric Vehicle Team of Virginia Tech is a collegiate automotive engineering design team that reengineers production vehicles to reduce environmental impact while maintaining vehicle marketability. The team Project Manager is responsible for coordinating high-level management and planning activities with the goal of better aligning the team with business and automotive industry practices. Project management responsibilities within the Hybrid Electric Vehicle Team are divided into four categories: human resource management, schedule management, cost management, and risk management. This document outlines how project management strategies were researched and adapted from industry practices for use by the Hybrid Electric Vehicle Team in achieving its goals. The human resource management strategy adopts onboarding principles that better prepare new students to become effective team members. By restructuring the organization and incorporating onboarding strategies, annual turnover is reduced from 71% to 44%. The decrease in turnover is enabled by the successful creation of an independent study program which trains newcomers to become effective team members. The program can be improved for the future by further developing the curriculum. The employed schedule management strategy develops the project schedule iteratively as technical information reveals itself through task progress. Utilizing this process makes schedule management possible in an environment with incomplete information and pressing deadlines. This strategy experienced limited success due to the lack of team and project scheduling experience on behalf of several key members of the process. The cost management strategy is designed to gather detailed financial data to perform an earned-value analysis and create improved budgets. By understanding income and expense patterns, the Project Manager can create economic forecasts to determine the economic viability of the team. The strategy was successfully implemented and allowed the team to gather valuable financial data. The risk management strategy identifies and quantifies technical risks associated with vehicle development. By focusing more resources on high-risk activities, the team can improve preparation for competition where the vehicle is judged according engineering quality and build progress. The strategy was successful because it identified critical hazards to the project schedule and scope, but can be improved by broadening the process to account for a wider variety of risks. / Master of Science

<p dir="ltr">Car design is a complex task because of how highly integrated system of systems it is. Fine?designed car models take years of design and optimization and are usually done by specialty teams who are dedicated to each sub-system. This thesis delves into designing a simplified electric race car from scratch with focus on the performance envelope of it. First, a 3D CAD model was done using SolidWorks. That section deals with spatial engineering and strategic placement of major car components for best performance. Having most of the parts in place gives a rough estimate of CoG (Center of Gravity) location, which is needed for vehicle dynamics analysis, which are discussed later in the report. The target for this project car is to have innovative aerodynamics features which might not have been used before because of bulky internal combustion engines restricting available space. One of them is an airfoil-like fascia which makes the center part of the car act as a one big wing. That is believed to give a significant reduction in drag loads on the car. The approach for aerodynamics design and analysis started with a model representing the car’s OML (Outer Mold line) which was simulated separately using Siemens StarCCM+. After understanding the car’s body aero behavior, a rear wing was added to provide extra rear downforce for better handling and stability. The rear wing design was explained in detail. Unfortunately, due to time restrictions as well as software access issues, the aerodynamic analysis of the full car with rear wing is left for future work. After having an estimate about aero loads acting on the car, vehicle dynamics analysis could start. The first subject studied in vehicle dynamics was front-view suspension geometry analysis. Taking the available packaging and geometry into consideration, a 2D model was done in SolidWorks to optimize camber gain. This analysis gave the motion ratio of the front and rear pushrod suspension system which was needed to analyze the performance of the one-eighth car model, ½ car pitch model, and ½ car roll model. These models gave insights into the decision-making process for spring and damping rates to reach a good balance between performance and comfort. This project acts as a hub for further development and studies related to car design.</p>

Modern automotive applications such as transmission clutch plates, combustion chambers, diesel fuel injector tips, and axle gears and friction plates operate at temperatures that can exceed 250°C and pressures of 40,000 psia. Industrial practice is to add homopolymers and copolymers to base oils to modify bulk fluid viscosity and frictional properties for these demanding applications. However, designing polymeric additives for lubricants and predicting their performance is limited by the lack of available high-temperature high-pressure (HTHP) viscosity and density data needed to test contemporary lubricity models. Thus, a major objective of this thesis is the design, development, and commissioning of a rolling ball viscometer/densitometer (RBVD) capable of simultaneously determining fluid densities and viscosities at temperatures in excess of 250°C and pressures of 40,000 psia. Resulting data may then be generated to directly address the fundamental need for lubricant property data at these HTHP conditions. The design and development of the RBVD is described in detail to highlight the design iterations and modifications utilized to ensure robust operation at extreme conditions. Three significant and novel features of this RBVD apparatus that distinguish and differentiate it from other apparatus of this type are: (1) specially designed metal-to-metal and sapphire-to-metal seated surfaces capable of eliminating temperature- and chemically-sensitive elastomeric seals; (2) use of a bellows piston to eliminate significant temperature and operational constraints; and (3) incorporation of a linear variable differential transducer (LVDT) to simultaneously permit determination of solution density and viscosity. A detailed analysis of initial accumulated uncertainty for the experimental viscosity and density techniques revealed the need for key RBVD modifications. Final data are presented showing that the RBVD is capable of measuring viscosities with an accuracy of ± 2 to 3 percent and densities to ± 0.7 percent, including at the extreme operating conditions targeted. A second objective of this thesis is the measurement of HTHP viscosities of star polymer-solvent mixtures to determine the impact of star polymer architecture on solution viscosity at extreme conditions similar to those that might be experienced in automotive applications. This objective is motivated by current challenges facing industry to identify polymeric additives that can be added to base oils to improve fuel economy and allow for the implementation of novel hardware technology that relies on enhanced lubricant properties. Relative to linear polymers, the unique architecture of star polymers enhances polymer solubility in base oils while having a more favorable impact on viscosity and density properties over a wide range of temperatures and pressures. Data are presented for an industrially-relevant star polymer in octane to assess the impact of the star configuration on solvent viscosity at extreme conditions. The star polymer used in this instance consists of an ethylene glycol dimethacrylate (EGDMA) core with poly(lauryl methacrylate-co-methyl methacrylate) (LMA-MMA) arms. The star polymer has a total weight averaged molecular weight (Mw) and Mw of each arm of 575,000, and 45,000, respectively. The copolymer arms of the star polymer have an LMA-to-MMA mole ratio of 0.6. The results of further viscosity studies are presented for a model system of well-characterized commercially available narrow polydispersity index (PDI) star polystyrenes (PS) in toluene. Each PS is evaluated at a two percent by weight concentration in toluene to evaluate the effect of arm molecular weigh on viscosity. Each three-arm star polymer has arm and total molecular weights ([arm Mw] total star Mw) of ([15,400] 41,200), ([36,000] 97,600), and ([108,000] 305,000). In this instance, the viscosity of toluene increased by more than a factor of three for the star with the highest Mw arms.

A concorrência no mercado automotivo vem aumentando nos últimos 10 anos, o que tem exigido das montadoras maior agilidade no desenvolvimento e lançamento de novos veículos, os quais devem atender aos requisitos e desejos dos clientes. Devido a isso, o uso de recursos e métodos no desenvolvimento que objetivem o atendimento aos requisitos de projeto, exigindo menos tempo para alcançar resultados satisfatórios e com menor custo desde as primeiras fases são diferenciais positivos para o novo projeto. O objeto de estudo do presente trabalho é o sistema limpador de para-brisa, e tem por objetivo propor uma metodologia computacional de otimização do sistema limpador de para-brisa a fim de obter a maximização da área de limpeza ao mesmo tempo em que encontra a configuração ótima do mecanismo considerando a sua mobilidade, o espaço disponível na carroceria para sua fixação e a qualidade do movimento oscilatório das palhetas. O desenvolvimento do modelo de otimização foi realizado em duas etapas, sendo a primeira a da otimização do posicionamento e orientação das palhetas visando a maximização da área de limpeza, e a segunda, a da otimização do mecanismo, onde buscou-se encontrar as dimensões ideais das peças do mecanismo, com o objetivo de maximizar os cursos de atuação das palhetas, limitando as amplitudes máximas das velocidades e acelerações angulares destas peças. A avaliação da metodologia foi realizada utilizando o programa MATLAB®, e como dados de entrada foram considerados sistemas limpadores de para-brisa existentes. Os resultados apresentados foram satisfatórios, pois a área de limpeza foi maximizada como também o mecanismo foi otimizado respeitando os limites impostos através de restrições. A metodologia proposta se mostrou uma potencial ferramenta de apoio no desenvolvimento de novos projetos, desde suas fases iniciais. / The competition among several existent brands of automobile industry has highly increased over the last 10 years. It leads all the companies to adopt methods to develop new models in a shorter period of time, but also focused on project requirements, quality and costs in order to satisfy the costumer. The main goal of this work is to propose a computational methodology optimization of the windshield wiper system in order to achieve the maximum wiped area by optimizing wiper blades lengths and orientations. Parallel to that, constrains make the methodology finds the optimum kinematic design for the windshield wiper linkage in terms of mobility, available area to fix the linkage on body and the maximum range of the blades oscillatory motion. The development has two stages: the first is the positioning and orientation of the blades optimization in order to maximize the cleaning area, and the second is the mechanism optimization, where it tries to find the optimum length of the mechanism`s links, also in order to maximize the cleaning area, at the same time it controls the maximum amplitudes of the angular accelerations and speeds of these links. The methodology evaluation was performed using the MATLAB® applied on an existent windshield wiper system of a domestic passenger car The results were satisfactory, since the cleaning area was maximized as well as the mechanism has been optimized within the imposed limits by constrains. The developed methodology has proved to be a potential tool in developing new projects, since the early phases of vehicle development.