So, that means this actually should be the unit vector.

这意味着这一项就是单位向量。

So, let me divide this by rho to get a unit vector.

除以ρ之后，就能得到单位向量。

This article presents the unit vector method for the full shaking force balancing of multi-loop spatial linkages.

本文提出了多环空间连杆机构摆动力完全平衡的单位向量法。

Now, how do we get this unit vector?

那我们怎么得到这单位矢量呢？

And this is the unit vector in the y direction and this is the unit vector in the z direction.

这则是y轴,方向的单位矢量,这是z轴,方向的单位矢量。

Now, another useful notion is the unit vector to the trajectory.

还有一个有用的概念就是轨道的单位矢量。