中文摘要：

首先建立3-PSS机构的位置方程，根据方程的特点，将该机构简化为一简单的等效机构，进而求出机构的位置正、反解的解析表达式。最后根据该机构的工作空间的特性，考虑了铰链摆动角的限制条件，给出了工作空间的解析式。本文所得的结果是进行3-PSS机构的其它特性分析和开发并联机构装备的基础。

英文摘要：

The kinematics equation of a new 3 dof parallel mechanism kinemacics was set up. According to the kinematics equation, the 3 - PSS was simplified to be an equivalent mechanism, and the forward and inverse kinematics solution was obtained. Taken into account of the constraint of joint angle, the closed - form workspace equation was given according to its characteristic. The research result provides foundation to analyze other characteristics of the 3 - PSS and develop its device.