The acs design for fully actuated spacecrafts is firstly discussed .

本文研究欠驱动航天器姿态控制系统的分析与设计问题。

The two spacecrafts rendezvoused successfully .

两宇宙飞船成功会合了.

Many countries have launched missiles and spacecrafts into outer space .

许多国家已向太空发射导弹和太空船。

Most of the early small unmanned spacecrafts use passive thermal control , due to its relatively low heat load .

早期小型无人航天器由于热负荷相对较小，多采用被动热控技术。

Currently testing tasks become heavier than before as the amount of various spacecrafts developed is increasing .

当前我国研制的航天器数目繁多，测试任务比以前更加繁重。