In this paper, the plan analytic geometry method is demonstrated to design the four-dar mechanism. The linkage is synthesized with plan motion theorem while three positions of connecting bar and two positions of revolutional center are specified.

• 本文介绍在四杆机构中；当已知连杆的三个位置以及两铰链中心时；可根据连杆平面运动的原理；用平面解析几何的理论来设计四杆机构.