行星齿轮变速机构运动学分析

用图论的方法对行星齿轮变速机构进行运动学分析。将基本行星轮系表示成三角形单元的形式，每个行星单元满足相应的运动方程。首先建立行星变速机构初始图论模型，根据控制元件结合情况，得到各个挡位的图论模型，再由相应的运动方程求解各个挡位传动比。以三自由度、两行星排行星变速机构和二自由度、四行星排行星变速机构为例，给出了系统的分析过程。该方法具有简单、规范、通用性较强、易于编程的特点，可适用于多自由度行星齿轮变速机构的分析。

Kinematic Analysis of Planetary Speed-shifting Mechanism

This paper presents a kinematic analysis method for the planetary speed-shifting mechanism. Using graph theory, a basic planetary gear train is represented by a triangular which corresponds to a kinematic equation. In the process of kinematic analysis, initial graph model for the planetary speed-shifting mechanism is first established. Based on combination of control elements, graph models of each of the states are obtained. Combining with kinematic equations, transmission ratio of each of the states is acquired. Systematic analysis processes are given by taking three-DOF (two planetary lines) and two-DOF (four planetary lines) speed-shifting mechanisms as illustrations. The method in this paper is simple, normative and programmable. It is workable for the planetary speed-shifting mechanism having multi-degree of freedom.