Approximate Linear Modeling of Pneumatic Artificial Muscle

The paper presents manufacturing a pneumatic artificial muscle (PAM) with the most basic shape and identifying it as an approximate linear model. To understand characteristics of the PAM, it is necessary to grasp the model well, but it is difficult to model pneumatic system due to its compressibility. Although the pneumatic pressure is basically nonlinear, we assume that it shows linear behavior within narrow operating region. The relationship between output force and input pneumatic pressure is acquired using conventional bode plot technique and derived as a linear transfer function.