中文摘要：

分析了超低空重装空投的空投流程，针对超低空重装空投飞行高度低、空投对象质量大的特点，把空投对象的位置和移动速度作为状态变量对货物移动时飞机运动的非线性方程进行了研究，该方程能准确描述出牵引伞的拉力、空投对象在货舱内的实时位置和移动速度对飞机姿态和高度的影响。同时，利用反馈线性化方法对模型进行输入输出线性化，并利用反步法与滑模控制相结合的方法，设计纵向滑模自适应控制器，解决了纵向不可参数化的不匹配不确定控制问题，实现了飞机在超低空重装空投时高度的稳定，保证飞机安全地完成超低空空投任务。

英文摘要：

This paper analyzes the procedures of super-low altitude heavy cargo airdrop. Because of the enormous quantity of the cargo and the super-low altitude of the airdrop, it is necessary to study the nonlinear movement equations of the plane taking the position and velocity of the cargo as the state variables. With this method, the equations can describe accurately the response of the altitude and posture of the plane, which are influenced by the traction of the parachute（s）, and the posi- tion and velocity of the cargo in real time. Meanwhile, the accurate nonlinear mathematic model is converted into a linear in- put-output model by means of feedback linearization, and a longitudinal adaptive sliding mode controller is designed based on the backstepping method which is able to solve the mismatching uncertain control problem for super-low altitude heavy cargo airdrop, keep the altitude of the plane steady, and ensure the safety of low altitude heavy cargo airdrop operation.