In order to explore the mechanism of bionic propulsion and bionic robots. to make up for the limitations of traditional propulsion with a uniform incoming flow. numerical methods are used to couple fluid dynamics and flapping foil motions. and a flapping-fluid coupling self-propulsion calculation model is established in this paper. https://www.diegojavierfares.com/flash-offer-A-D-EJ-123-Newton-Compact-Balance-Scale-120-x-0-001-g-hot-grab/