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This paper discusses the problem of designing electric machines (EM) for advanced electric generators (AEG) used in aerospace more electric architecture (MEA) that would be applicable to aircraft, spacecraft, and military ground vehicles. The AEG's are analyzed using aspects of Six Sigma theory that relate to critical-to-quality (CTQ) subjects. Using this approach, weight, volume, reliability, efficiency, and cost (CTQs) are addressed to develop a balance among them, resulting in an optimized power generation system. The influence of the machine power conditioners and system considerations are also discussed. As a part of the machine evaluation process, speeds, bearings, complexities, rotor mechanical and thermal limitations, torque pulsations, currents, and power densities are also considered. A methodology for electric machine selection is demonstrated. Examples of high-speed, high-performance machine applications are shown.

Due to the wide and ever increasing application of thermoplastic parts in the automotive industry, the measurement and interpretation of their properties must be thoroughly understood before anyone can hope to correctly utilize the results in material selection, product design, and performance analysis while all these can be greatly influenced by the end-use conditions. Tensile properties of thermoplastics, such as stress and strain at yield, ultimate tensile strength, and Young's modulus, are among the most widely measured and cited mechanical properties for material evaluation, quality control, structure design, modeling, and failure analysis. This paper deals with several major challenges that an engineer may face when attempting to obtain accurate tensile property data for thermoplastics. One such challenge is the trend of automotive industry today to convert from ASTM to ISO procedures for thermoplastics evaluation and product certification.