说明：  根据系统的输入和输出，辨识系统的的传递函数。该系统为6阶系统，通过降阶降为2阶后，加入状态反馈和状态观测器，调整参数使2阶系统稳定，最后用于控制原6阶系统。阶跃响应和bode图效果都不错。
(Based on the input and output of the system, the transfer function of the system is identified. The system is a 6 order system. After the order is reduced to 2 order, the system is added with the state feedback and the state observer, which adjusts the parameters to make the 2 order system stable. Finally, it is used to control the original 6 order system. Step response and Bode figure results are good.)