Tribologically-based design of precise positioning stage

To produce modem engineering system in which high specification is required, tribology becomes an essential design input to achieve ultimate performance. A new concept of machine design from a viewpoint of tribology is therefore necessary: "Tribologically-based machine design, defined as design of the overall system based on to achieve ultimate tribological performance" in addition to the more conventional "design of a reliable mechanical element based on tribological understanding." In this paper, a compact and highly-precise linear positioning stage driven by friction with an ultrasonic motor is proposed for use in an electron-beam direct-writing system, and is realized by the optimum design of the overall system, including tribological materials and operating conditions, using the concept described above. It provides a size reduction to one half of the conventional stage, and a positioning precision which is three times as great.