The mechanical environment is described in the paper and then the environments in three different orbits are proposed , called leo ( low earth orbits ) , meo ( medium earth orbit ) and geo ( geosynchronous earth orbits ) . the influence produced by the atomic oxygen , micrometeorites and debris , ionizing radiation and cold welding under vacuum is presented in the paper . some principles are proposed , which can be as the method to choose materials of the mechanism in space environment 空间环境中力学环境对可动结构的影响直接关系到机构的设计问题，所以本文第四章中岳建如：中文摘要浙江大学博士学位论文20024首先详细论述了空间环境中的力学环境，然后给出了空间环境的三种轨道环境划分，及每一种环境影响因素对空间可动结构设计的影响，包括原子氧、离子射线、温度、微陨石和碎片以及真空冷焊现象等环境因素，提出了材料选择的原则，为可动结构材料选择提供了一定的依据。
