Mathematical Model of Pneumatic Artificial Muscle Reinforced by Straight Fibers

ABSTRACT: This article describes a mathematical model of a pneumatic artificial muscle reinforced by straight fibers. The pneumatic artificial muscle is lightweight and high power. In addition, it is possible for it to emit exhaust into the atmosphere because the transmission medium of its energy is air, and it needs neither a tank nor maintenance like hydraulic equipment. In addition, safety to a person and the environment is high because the base of the actuator is a soft polymeric material even if damage to the artificial muscle is caused. On the other hand, because the device is composed of a thin film cylinder, and is easily influenced by outside power for the conversion of the volume change in rubber into physical contraction axially, and its passive character is strong, precise positional control is difficult. However, the living thing that has a verbose degree of freedom enables minute motion and walking, etc. by skillfully adjusting to avoid impedance, because it understands its own muscular characteristic beforehand. Similarly, it is thought that the precise positional control is possible by understanding the characteristics of an artificial muscle beforehand. In this research, it is assumed that the expansion shape of the pneumatic artificial muscle that we developed from the pressure distribution is equivalent to the centenary curve, and its model is based on dynamic balance. The result shows the effectiveness of control of an artificial muscle that uses highly accurate calculations and models. Key Words: pneumatic actuator, artificial muscle, mathematical model, contraction characteristic