说明：  使用非定常涡格法(UVLM)计算一种简单扑翼机的升力。对应文献Time Domain Modeling of Unsteady Aerodynamic Forces on a Flapping Airfoil -Eric Durand（MIT Master thesis）
(Unsteady vortex lattice method (UVLM) a simple flapping wing machine lift. Corresponding literature Time Domain Modeling of Unsteady Aerodynamic Forces on a Flapping Airfoil-Eric Durand (MIT Master thesis))