A computational tool to improve flapping efficiency of robotic insects

We implement a 2D computational model to investigate the unsteady aerodynamic effects not captured by classical quasi-steady models. We compare numerical simulation results, experimental measurements and quasi-steady predictions to demonstrate the strength of the numerical tool in identifying unsteady fluid mechanisms and improving propulsive efficiency of flapping wing robots. In particular, this study quantifies the effect of the relative phase between wing degrees of freedom δ on lift and drag production. The computational model also identifies unsteady effects such as wake capture and downwash that are not accounted for in classical quasi-steady models. To examine the accuracy of our computational model, we fabricate millimeter-scale wings through the SCM fabrication processes and measure flapping kinematics and dynamics. The experiments show 2D computational model is 44% more accurate than the quasi-steady model and can be further used to improve wing morphology for better aerodynamic performance.