Accelerating of characteristic estimation of seismic motion and switching control for air type anti-vibration apparatus by using DI value

Abstract

This paper shows estimation of earthquake using destructive intensity (DI) value and its application to switching control for air type anti-vibration apparatus (AVA). Air type AVAs are used for suppression of vibration in precision machining field like semiconductor manufacturing. Since even slight vibration is not excused, seismic motion which occurs in rare becomes a problem. Previous work switched control of the AVA by using spectrum intensity (SI) value when seismic motino occurs. However, the calculation of SI value has computational complexity and requires long computation time. In order to solve this problem, observation points were created in the distance from the AVA. Since this method leads to the increase of cost, it is difficult for an enterprise to use observation points. This paper proposes control system which estimates property of earthquake using only location of the AVA. In particular, to estimate earthquake uses DI value instead of SI value. This value has a characteristic which is that the computation time is short. This approach estimates characteristic of seismic motion by using both DI value and property of the AVA. Moreover, control of the AVA is switched. Simulation results demonstrated that DI value estimates property of seismic motion faster than the conventional method and proposal method could properly switch controller of AVA in the same way as the previous method. In addition, using DI value to detection way of seismic motion proves that this way can switch faster than the conventional method.

Keywords

• pneumatic equipment
• seismic motion
• spectrum analysis
• spectrum intensity
• destructive intensity