Active Pneumatic Vibration Isolator With Pressure Feedback

Abstract

This paper presents research on effectiveness of P-control algorithm with a pressure as an output signal for an active vibration isolator using pneumatic bellow. Pressure pulsation inside the pneumatic element of the vibration isolator is studied in the frequency range covering its sub resonant and resonant frequencies. Spectral analysis is used to compare the response to harmonic excitation of active pneumatic vibration isolator and that for the case with active control disabled. The minimal bore size of the control valve is defined to achieve a double advantage of the active system over the passive one in the frequency range including the vibration isolator resonant frequency. It is shown that to obtain this result, a fast-acting spool valve should be used. Moreover, at a low frequency range of a Hertz-level excitation signal, P-control algorithm demonstrates three times decrease of pressure pulsation amplitude. The analysis of experimental results shows that P-control algorithm with pressure output and the high response spool valve with the bore size as large as possible can be used for active pneumatic vibration isolator at the low frequency range.

Assessing the Efficiency of the Air Isolation System Based on the Mathematical Models

“…The AIS was designed by an airbag chamber connected with an auxiliary chamber via the pipe, 4,[10][11][12][13]22 as shown in Fig. 1a.…”

“…The airbag chamber was connected with the auxiliary chamber via the pipe. 3,4,[11][12][13] To evaluate the isolation efficiency of the AIS, based on the thermodynamic theory, the structure and design parameters of the AIS were researched and analyzed via the characteristics of the force response-time, force-deformation, and force-frequency of the airbag chamber. 14,15 The experimental study of the AIS was also performed to validate the results of theoretical research.…”