Supporting Information Caterpillar Locomotion–inspired Valveless Pneumatic Micropump using Single Teardrop-shaped Elastomeric Membrane

Theoretical Model To design a simple teardrop-shaped membrane, two circles with radii of 2 mm and 0.5 mm, were connected by tangent lines. The two circles were spaced as much as 5 mm apart, from center to center. The shape of the chamber underneath the teardrop-shaped membrane was also the same as that of the membrane. The thickness of the membrane and the height of the chamber were 20 μm and 200 μm, respectively. For the theoretical estimation of the teardrop-shaped membrane, the simplified model based on the consecutive circular membranes with different radius was suggested as shown in Fig.S1A. Typical analytic relationship between the static pressure and deflection for a circular membrane with the radius (r), thickness (t), elastic modulus (E), and Poisson’s ratio (ν) is given by