부산대학교 도서관

The present work deals with a system attached to a mass and a Pneumatic Artificial Muscle (PAM) actuator with time-varying pneumatic pressure which results in a direct and parametrically excited system. The governing differential equation of motion is solved using the second-order method of multiple scales (MMS) and the closed-form equations are determined. With the help of these equations, the parametric instability regions have been studied for simple and principal parametric resonance conditions. The influence of different muscle parameters, damping, amplitude and frequency of the time-varying pressures on the instability regions are investigated and verify with the help of time response and phase portraits. This study can be useful for designers and researchers to get an idea about the critical values and safe operating range of different parameters of the PAM. [ABSTRACT FROM AUTHOR]