A consideration of switching control based on priority of earthquake which is analyzed in observation area as far from an air type anti-vibration apparatus

Abstract

This paper presents the control method for the continuous operation of air type anti-vibration apparatus under earthquake ground motion. Air type anti-vibration apparatus is essential for semiconductor exposure machine. When earthquake ground motion strikes, the process of the stopping semiconductor exposure machine is often executed. It leads to low production throughput of semiconductor devices. In previous study, we show that there is a tradeoff between the acceleration of the table and the relative displacement. By switching control based on this tradeoff, the vibration of the acceleration of the table or the relative displacement can be suppressed under earthquake ground motion. However, this method cannot suppress immediately the acceleration of the table or the relative displacement when earthquake ground motion strikes. This paper extends method of this switching control. Concretely, observation area as far from air type anti-vibration apparatus is created. This observation area analyzes the priority of earthquake ground motion. The logic for analyzing the priority of earthquake ground motion explains. By utilizing the priority of earthquake ground motion, the faster switching control attempts. In this simulations, earthquake ground motion which occurred at past is used. Furthermore, we perform experiment with the switching control. This experiment shows that transient response does not occur when the control is switched under vibration.

Keywords

• seismic motion
• vibration isolation
• earthquake resistant
• spectrum analysis
• motion control