中文摘要：

欠驱动系统是一类构成系统的广义坐标维数多于控制输入维数的非线性系统。旋转摆属于典型的欠驱动系统，通过驱动杆的水平转动可使欠驱动杆由垂直下摆位置转到竖直向上位置。利用基于能量的控制方法设计了摇起控制器，使欠驱动杆由稳定平衡位置到达非稳定平衡区域，再由LQR方法设计平衡控制器，使其控制在非稳定平衡位置。两种控制器通过切换实现摇起和平衡控制转换。最后通过仿真实验验证了文中设计的两种控制器的有效性。

英文摘要：

Underactuated systems are a class of nonlinear systems that the dimension of generalized coordinates more than the dimension of control input. The rotating pendulum is a typical underactuated system with a rotating shaft of the motor attached to the end which is free to spin about an axis parallel to the axis of rotation of the pendulum. The control objective is to swing it up from a stable downward equilibrium position to the unstable straight up equilibrium position by the rotating arm. By using the method of the energy-based and LQR, a swing up controller and a balancing controller were designed. Two controllers were properly transformed by using switching. The simulation results show that the proposed method is effectiveness.