The technology of soft landing is one of the most important technologies of heavy cargo airdrop system. As the cargo lands in a great velocity during the process of heavy cargo airdrop,it is necessary to take some cushion measures to ensure the safety and stability of soft landing, so the airbag cushion system is widely used. Against the backdrop of Defense Pre-research project, based on the finite element method, contact dynamics, elastic-plastic mechanics, rigid-body dynamics and optimal design theory, st...