The Pneumatic Artificial Muscle (PAM) has great potential in industrial, robotic and prosthesis applications because of the extreme power to weight ratio, high strength and scalability for different purposes. However it is hard to control without precise modeling because of its high nonlinearity. In this paper we present our more accurate transfer function in comparison with other approaches. Finally we present the design and experimental testing of an open looped position controller for PAM actuator using the inverse of the transfer function.