Mechanical Engineering Commons^™

Top-Down & Bottom-Up Approaches To Robot Design, Dylan Michael Covell

Graduate Theses, Dissertations, and Problem Reports

This thesis presents a study of different engineering design methodologies and demonstrates their effectiveness and limitations in actual robot designs. Some of these methods were blended together with focus on providing an easily interpreted project design flow while implementing more bottom-up, or feedback, elements into the design methodology. Typically design methods are learned through experience, and design taught in academia aims to shape and formalize previous experience. Usually, inexperienced engineers are taught approaches resembling the Verein Deutscher Ingenieure (VDI) 2221 process. This method presented by the Association of German Engineers in 2006 is regarded as the general system design process. …

Measured And Modeled Performance Of A Spring Dominant Free Piston Engine Generator, Ramanjaneya Mehar Baba Bade

Graduate Theses, Dissertations, and Problem Reports

Free Piston Engine Generators (FPEG) directly convert the reciprocating piston motion into electricity by using a linear alternator. Unlike conventional engines with piston motion restricted by a crankshaft mechanism, the FPEG piston motion is constrained by the energy available in the system. When stiff springs are considered in the design, the FPEG system attains high frequency with high power and efficiency. The main objective of this research was to model stiff spring-assisted FPEG system dynamics and performance accurately, and to apply the modeling results to the development of a 1kW, spark ignited, natural gas fueled, FPEG experimental prototype. The experimental …

Design And Optimization Of Dynamic System For A One-Kw Free Piston Linear Engine Alternator-Gensets Program, Nima Zamani Meymian

Graduate Theses, Dissertations, and Problem Reports

In power/energy systems, free-piston linear machines are referred to as a mechanism where the constrained crank motion is eliminated and replaced with free reciprocating piston motion. Depending on the application, the piston motion can be converted into other types of energy and includes compressed air/fluid, electricity, and high temperature/pressure gas. A research group at West Virginia University developed a free-piston linear engine alternator (LEA) in 1998 and have achieved significant accomplishment in the performance enhancement of the LEAs to date. The present LEA design incorporates flexure springs as energy restoration components and as bearing supports. The advantages of using flexure …

Electroplating Of Cr-Ni Alloy And Ni-Cr/Ni Multilayer Coatings, Liaowang Liu

Graduate Theses, Dissertations, and Problem Reports

The major interests of developing Ni-Cr alloy plating lie in the possible formation of a passive film by chromium and its good chemical and mechanical properties. And nano scale multilayer coatings exhibit improved properties due to nano scale effects (e.g.: high hardness and strength) and they combine and enhance different properties from individual components. Thus, electroplating of Ni-Cr multilayer coatings could have high potential for numerous engineering applications. Electroplating in aqueous and in organic solution by direct current were studied for Ni-Cr alloy coatings, and Ni-Cr multilayer coatings were prepared by pulse current electroplating in single bath.

Traditionally, chromium or …

Mode And Implementation Of A Hybrid Control System For A 2-Mode Hybrid Electric Vehicle, Zhenhua Zhu

Graduate Theses, Dissertations, and Problem Reports

Automotive transportation consumes more than 71% of the world's total petroleum energy. The vehicle will have to use less because it will take less than 30 years to consume the rest of the proven conventional oil reservoir if the fuel consumption keeps the current trend. One of the methods to improve the vehicle efficiency is to develop Hybrid Electric Vehicle (HEV). An HEV combines an internal combustion engine (ICE) and electric motor(s) powered by batteries or capacitors to achieve better fuel economy. Among the HEVs, 2-Mode HEV combines an ICE and two electric motors with two planetary gear sets and …

Multiregional Interactions Between Energy And Transportation, Karen R. Polenske

Applications

Because of the number and complexity of the issues that will determine the use of coal by the electric-generating plants, an important asset of policy makers will be the availability of a method of analysis that allows for quick studies of many different combinations of assumptions and policies. The present prototype study is designed to show how the multiregional input-output model can be used to investigate each different assumption and policy alternative. For this paper, the analysis has necessarily been restricted to two issues. First, the results of using regional rather than national technologies in the model are assessed. This …