中文摘要：

针对阀控中空液压摆动马达系统，建立数学模型；基于LuGre动态摩擦模型，设计摩擦状态观测器；在此基础上，通过提出带状态观测的滑模变结构控制算法进行大摩擦力矩动态补偿控制，并进行了试验研究。结果表明：所设计的摩擦状态观测器可以较好地估计摩擦力矩，基于状态观测的滑模变结构控制算法可以实现大摩擦力矩下的高精度轨迹跟踪，相比无状态观测的滑模控制，轨迹跟踪精度提高1个数量级以上。

英文摘要：

The hollow hydraulic motor is a key assembly unit for inner frame driving of multi-axis huge inertia motion flight simulator. However the large friction caused by its special structure seriously influences the tracking performance and positioning precision of the servo system especially at very low velocity. A mathematical model of the valve-based hollow hydraulic motor servo system was established. The friction state observer was proposed based on the LuGre dynamic friction model. On this basis, the sliding mode variable structure control algorithm with friction state observer was developed to compensate the friction torque, and the experiment was carried out. The result shows that the proposed state observer can estimate the friction torque correctly, and compared to that without observer, the sliding mode controller with observer can get more precise trajectory tracking.