说明：  实验看起来很烦琐，仔细分析，机构间的联系，困难也会迎刃而解。本次实验的困难，主要集中在机构的连接上，首先确定原点，也就是基点，线以及其他构件，照着点与点的关系顺序建立起来，最终将整个机构连接起来。
(The experiment looks very cumbersome, careful analysis, inter agency links, difficulties will be solved. The difficulty of this experiment is mainly focused on the connection of the mechanism. First, the original point, that is, the base point, the line and other components, is set up in the order of the relation between point and point, and finally the whole mechanism is connected.)