self-propulsion point of ship under tank condition

例句：

1. 1.The self-propulsion system of the ship is crucial for its navigation.
   船的自推进系统对于其导航至关重要。
2. 2.The autopilot uses sensors to control the ship's self-propulsion.
   自动驾驶仪使用传感器来控制船的自推进。
3. 3.The propulsion system on board the spacecraft provides power for its self-propulsion.
   太空船上的推进系统为它的自推进提供动力。