回转轴

例句：

1. 1. The car's steering wheel is a rotating axis that allows you to adjust the direction of travel.
   汽车的方向盘是一个可旋转的轴，允许你调整行驶方向。
2. 2. The machine's gearbox is a turning axis that connects the engine to the wheels.
   这台机器的变速箱是一个连接发动机和车轮的转动轴。
3. 3. The robot's arm is a rotating axis that can rotate and move in different directions.
   这个机器人的手臂是一个可旋转的轴，可以在不同的方向上旋转和移动。