This is hard to achieve with rigid bearings and could lead to strange new modes of locomotion, allowing robots to walk or roll, depending upon which is more appropriate.

这用刚性轴承是难以实现的，它将衍生出一种全新的移动模式，机器人将或走或滚，全看哪种方式更合适而已。

youdao

Presents a space motion model (SMM) of multiple rigid bodies with varying mass for the description of the intercept problem of homing missiles with roll stabilization.

已经发表的自寻的非滚转导弹拦截问题的数学模型往往是平面模型或空间质点模型。

youdao

The melody he had in mind was based on an old "Tattoo" a rigid bugle call that summoned soldiers for the day's last roll call.

WSJ: Tapping into "Taps"