Multi-physics system modeling of a pneumatic micro actuator

We present a first step in the conception of a micro pressure source. It consists in three main parts: (i) a heating resistance built on a dielectric membrane, (ii) air encapsulated at atmospheric pressure and (iii) an elastomer membrane with high elastic properties. A PDMS-based material is chosen as the membrane material for its elastic properties. When the actuation is required, air is heated to increase its pressure; the gain in pressure produces the deformation of the elastic membrane. Physical models have been developed for each step of operation: the heating of the resistance, the air pressurization and the elastic membrane deformation. An important model feature is the coupling of air pressurization with membrane deformation. This paper presents each individual model that has been correlated with experimental results. Then, all the models are implemented into one system model used to predict the actuator performance as a function of input electrical signal.