Stephen P. Radzevich, MS, PhD, Sc.Dr., is Principal, R&D Gear Transmission Engineer and retired Professor of Mechanical Engineering and Manufacturing Engineering in Michigan. He has nearly 50+ years in industry and academia creating software, hardware, and other processes for gear design and optimization. He has written numerous books and papers on gears and gear technologies, and holds patents for relevant inventions. Most of his career Dr. S.P. Radzevich spent working in one of two capacities: (a) as a university professor, Mechanical Engineering Department, and (b) as a Principal R&D Gear Transmission Engineer for the automotive industry, aerospace industry, and so forth.