The idea that what works for insects or small birds should work in larger scale if you just have materials does not hold up. Small insect wing aerodynamics is

The idea that what works for insects or small birds should work in larger scale if you just have materials does not hold up. Small insect wing aerodynamics is closer to high viscosity aerodynamics. Viscous forces are more important and efficacy of lift generation from an airfoil is less important. Air can be considered incompressible. Reynolds numbers (Re) - orders of magnitude. 10^7 for helicopter main rotor 10^4 for large insects 10 for small insects Helicopter rotor aerodynamics is in laminar flow region limited from above buy the transonic region. Airfoil lift is the most important thing and laminar flow is important. Insect flight is mostly turbulent flow. Generating enough lift using leading edge vortex and half strokes like insects do for helicopter sized object and rotor sized wing is not self evident. At least the wings should be much larger than helicopter rotors and flap very slowly.