基于渐开线球齿轮的机器人柔性手腕结构与运动分析

介绍了一种基于渐开线环形齿球齿轮传动的机器人新型柔性手腕及其空间八杆驱动机构。该柔性手腕由六个球齿轮按特定规律串联而成,构成了一种多系杆的空间运动行星轮系机构。新型柔性手腕具有3自由度,可实现全方位偏摆运动和自旋运动,任意方位最大偏摆角可达126°,其运动性能明显优于著名的Trallffa柔性手腕。介绍了多个球齿轮的串联结构型式,分析了新型柔性手腕的结构特点和动作原理。对驱动机构进行了可动性分析,建立了驱动机构的运动学模型。分别进行了手腕偏摆运动分析和自旋运动分析,利用Denavit-Hartenberg方法确定了六个球齿轮的位姿矩阵,推导了手腕输出轴偏摆角与第一级系杆框架偏摆角之间的关系,并求出了输出轴末端的坐标参数方程,建立了自旋运动正、逆问题运动学模型。上述驱动机构和柔性手腕的运动学分析模型成为设计控制系统的依据。

WHICH IS BASED ON THE INVOLUTE SPHERICAL GEAR CONSTRUCTION AND KINEMATICS ANALYSIS OF THE ROBOT'S FLEXIBLE WRIST

One new kind of robot wrist which is composed of ring involute spherical gear and driven by eight-bar linkages is introduced. The new robot wrist is composed of six spherical gears, all these spherical gears are linked one to another in series. The robot wrist is one of multi-bracket gear train with spatial motion. The new wrist has three degree of freedom and can oscillate towards any orientation. The maximal oscillating angle equate to 126? The motional performance is far better than that of famous Tral-lffa robot wrist. The construction type of series-mounting with more than two spherical gears is introduced. The characteristics of wrist's structure and its action theory are analyzed. The mov-ability of driving linkages is also analyzed, and its kinematics model is built up. Then the analysis of the oscillating motion and cir-cumgyrating motion of robot wrist is accomplished. The position and orientation matrix of six spherical gears in wrist is determined by Denavit-Hartenberg method. After deducing the relationship of tow oscillating angle between output axis and first bracket, the position of end point of output axis is determined. The kinematics and inverse kinematics model of circumgyrating motion of robot wnst are founded. The kinematics model of diving linkage and robot wrist is the gist for designing control system.