Abstract: For the realization of under-actuated Autonomous Underwater Vehicle（AUV） in unknown disturbance currents under the control of path following，an increment feedback control method based on nonlinear iterative sliding mode control is presented.Using common curve parameters and the serret-frenet coordinate system describes the path tracking error，the equation of AUV horizontal tracking error is established.Incremental sliding mode feedback controller is designed by iterative method without uncertainty parameter of AUV model and current disturbance estimation.The results of simulation experiments show that the controller is easy to be adjusted，can be used in the actual under-actuated AUV to track the desired horizontal path precisely.

Key words: under-actuated autonomous underwater vehicle, path-following, iterative sliding mode, curve parameters

摘要： 为实现欠驱动自治水下机器人（AUV）在未知海流干扰作用下的路径跟踪控制，提出一种基于非线性迭代滑模增量反馈的路径跟踪控制器。选用一般曲线参数和Serret-Frenet坐标系描述路径跟踪误差，建立AUV水平面路径跟踪误差方程。采用迭代方法，设计滑模增量反馈控制器，无需对AUV模型参数不确定部分和海流干扰进行估计。仿真实验表明，设计的控制器参数易于调节，可用于实际欠驱动水下机器人来实现对水平面路径的精确跟踪。

关键词: 欠驱动自治水下机器人, 路径跟踪, 迭代滑模, 曲线参数