A novel triple-actuating mechanism of an active air mount for vibration control of precision manufacturing machines: experimental work

• Published in: Smart materials and structures Vol. 23; no. 7; pp. 1 - 8
• Main Authors: Kim, Hyung-Tae, Kim, Cheol-Ho, Choi, Seung-Bok, Moon, Seok-Jun, Song, Won-Gil
• Format: Journal Article
• Language: English
• Published: Bristol IOP Publishing 01.07.2014; Institute of Physics
• Subjects: Active control; Actuators; air mount; electromagnetic actuator; Exact sciences and technology; General equipment and techniques; Instruments, apparatus, components and techniques common to several branches of physics and astronomy; Logic; magnetorheological damper; Physics; pneumatic actuator; Pneumatics; Semiconductors; Transducers; Transient responses; Vibration; Vibration control; Actuators; Transient response; Electromagnetic actuators; Precision engineering; Displacement sensor; Measurement sensor; Pneumatic systems; Impact tests; Magnetorheological fluid; Active system; Displacement measurement; Vibration control; Non linear effect
• ISSN: 0964-1726; 1361-665X
• DOI: 10.1088/0964-1726/23/7/077003

With the goal of vibration control and isolation in a clean room, we propose a new type of air mount which consists of pneumatic, electromagnetic (EM), and magnetorheological (MR) actuators. The air mount is installed below a semiconductor manufacturing machine to reduce the adverse effects caused by unwanted vibration. The proposed mechanism integrates the forces in a parallel connection of the three actuators. The MR part is designed to operate in an air spring in which the EM part is installed. The control logic is developed with a classical method and a switching mode to avoid operational mismatch among the forces developed. Based on extended microprocessors, a portable, embedded controller is installed to execute both nonlinear logic and digital communication with the peripherals. The pneumatic forces constantly support the heavy weight of an upper structure and maintain the level of the air mount. The MR damper handles the transient response, while the EM controller reduces the resonance response, which is switched mutually with a threshold. Vibration is detected by laser displacement sensors which have submicron resolution. The impact test results of three tons load weight demonstrate practical feasibility by showing that the proposed triple-actuating mechanism can reduce the transient response as well as the resonance in the air mount, resulting in accurate motion of the semiconductor manufacturing machine.