center-of-mass coordinate的意思|示意

So, switching the area, moving the area to the other side, I'll get double integral of xdA is the area of origin times the x coordinate of the center of mass.

那么，改变一下区域，把这块移到另一侧，我们得到对xdA的双重积分,是原点那的圆面积乘质心的x的坐标。

As to the conservation of motion of center of mass, the method of absolute coordinate system is generally used in the teaching meterials of theoretic mechanics.

对于质心运动守恒问题，理论力学教材中一般用绝对坐标法进行计算。

And then using mass center formula to calculate four parameters of translation axes and rotation coordinate, mathematic model is established.

然后采用重心公式计算出坐标平移旋转的4个参数，建立了坐标平移旋转的数学模型。