中文说明：四旋翼的结构简图如图2所示。四个旋翼分布在十字形支架的四个顶点，依次编号为1、2、3、4。飞行时，一组（1、3）旋翼始终逆时针旋转，二组（2、4）旋翼始终顺时针旋转。该内容包含对应的控制仿真模型以及对应的报告。
English Description：
The structural diagram of the quadrotor is shown in Figure 2. The four rotors are distributed at the four vertices of the cross bracket, numbered 1, 2, 3 and 4 in turn. During flight, the rotors of group 1 (1,3) always rotate counter clockwise, while the rotors of group 2,4 always rotate clockwise. The content includes the corresponding control simulation model and the corresponding report.