平面四连杆机构近似位姿综合的计算机模拟逼近法

Computer Simulation of Approximate Dimensional Synthesis with Four Bar Linkage

平面连杆机构尺寸综合的两个基本工具是几何法和解析法 ,它们仅适用于规定较少的机构精确位姿数的综合 .几何法简单直观 ,但求解精度低且重复性差 ;解析法求解精度高且重复性好 ,但求解复杂、不直观 .针对两种方法的缺点 ,提出一种机构尺寸驱动综合方法 ,即连杆机构近似位姿综合的计算机模拟逼近法 .首先在多个复合精确和近似位姿情况下 ,用 CAD的几何约束和尺寸驱动技术 ,构造一个基本四连杆模拟机构 ;再根据函数、轨迹和运动综合的原则 ,由基本四连杆模拟机构分别构造出函数、轨迹和运动的近似位姿综合模拟机构 .计算机模拟结果表明 ,这种方法不仅具有简捷直观、求解精度高和重复性好的优点 ,而且可以增加机构综合的规定位置个数 。

Two basic tools of dimensional synthesis are geometric construction and analytical calculation, but few available number of prescribed positions may be assigned for dimensional synthesis, and analytical calculations are quite complicated and far from straightforward. A novel computer simulation mechanism for approximate dimensional synthesis with four bar linkage is presented. In thecase of assigning ten points with given precision and approximation allowance, using the geometric constraint and dimension driven techniques, a primary simulation mechanism with four bar linkage is created. Different tasks of function synthesis, path synthesis, and motion generation for the approximate dimensional synthesis were accomplished.