Any processes in a manufacturing system are performed by machines in one form or another. A machine is a mechanical structure that transfers power or movement in an intended action. A machine consists of both fixed parts and moving parts. Fixed parts keep still relative to a reference base and moving parts change their positions with time while being in machine operation. Moving parts or components are mostly built upon machine elements such as flywheels, pulleys, belts, linkages, conjugate cams, spindles, chains, cranks, and gears.