Fig. 3.
Finite element method (FEM)-based simulation of the expanded PDMS balloons at fixed air pressure of 14 kPa. (a) The simulation result of the 2.0 mm-diameter PDMS balloon provides detailed information on the deformation of the balloon such as stress concentration. h and D are the center height and diameter of the PDMS balloon, respectively. (b) Profiles of the expanded PDMS balloon measured by 3D laser scanning microscopy and FEM simulation show good agreement.