Self-identification method of arrangement and effective pressure areas for a vibration-isolation table supported with a redundant number of pneumatic actuators

Abstract

For the purpose of developing a vibration-isolation table with flexibility and/or scalability (which means “with adaptability to desired load specification”), this study investigates a self-identification method with regard to positions or arrangement and effective pressure areas of pneumatic actuators which support a vibration-isolation table. The proposed identification method is a fundamental technique necessary to construct a scalable vibration-isolation table in which the actuators supporting the table can be added or removed flexibly according to the load demand, easily, and in a short period of time. First, this study constructs a mathematical model for a vibration-isolation table supported by a redundant number of actuators and a type 1 digital servo controller to control the position and inclination angles of the table. Next, we derive the identification method for obtaining the position of the added pneumatic actuator and the effective pressure areas of the pneumatic actuators. We then demonstrate the proposed identification method by numerical simulations using our detailed mathematical model. Finally, this study shows an example of the application of the proposed identification method coupled with a force redistribution technique by addition of an actuator into the vibration-isolation table system during continuous operation. The validation and success of our method was confirmed by the displacement and pressure responses of the vibration-isolation table.