A comparison study on Pneumatic Muscles and electrical motors

Pneumatic artificial muscles also known as ldquoPAMrdquo and ldquoPMrdquo, are famous as very light actuators in the current literature. The reason stated in the literature for such claim is their lower ldquopower to weightrdquo ratio compared to other type of actuators namely pneumatic cylinders and electrical motors. However using the ldquopower to weightrdquo ratio of actuators for claiming the lightness of an actuator is questioned in this paper, and a new approach for such comparison is introduced. In this paper a comparison study was made between electrical rotary actuators and PMs on the basis of the taualpha value. It is showed that claims which consider PMs as lighter actuators compared to the other types of actuators are not precise and are highly questionable since some factors are neglected in comparison between the weight of the actuators.