带有预定时标平面四杆刚体导引机构尺度综合的研究

STUDYONDIMENSIONSYNTHESIS OFPLANARLINKAGESFOR RIGID-BODYGUIDANCE WITH PRESCIBEDTIMING

提出并解决了利用连杆转角函数谐波成分“数值图谱”进行带有预定时标刚体导引机构尺度综合的计算机方法。在分析了刚体导引位置转角函数与连杆转角函数之间的内在联系及解决了用理论计算方法确定机构实际尺寸、连杆上标线的位置及机构安装尺寸参数关键问题的基础上， 以曲柄摇杆机构为例， 用该方法建立了一个含有２０３５０ 组机构基本尺寸型连杆转角函数的谐波成分数据库。从而可以通过模糊识别方法在已建立的数据库中快速寻找出能够实现给定带有预定时标刚体导引的多个机构， 达到近似实现带有预定时标要求刚体导引机构的尺度综合。给出的算例充分说明了本方法的有效性与优点。

A com puter m ethod is firstly proposed, w hich is used to do the dim ension synthesis ofplanar 4 bar linkages for rigid body guidance w ith Prescribed Tim ing (in short PT) by harm onic com ponent's database ofthe coupler's ro tation angle function. The relationship betw een position function ofrigid body guidance w ith PT and coupler's rota tion angle function of4 bar linkage is analyzed. The key of the m ethod is to solve the real dim ension of linkage, coupler's point position and installing dim ensions of the linkage. Based on solving the problem , a harm onic com ponent's database of the coupler's rotation angle func tion including 20350 dim ensional types, taking the crank rockerlinkage asan exam ple, is established. So, itis possi ble to choose som e linkages from the database to realize rigid body guidance w ith PT by using fuzzy identification m ethod quickly, and to approxim ately achieve “infinite posi tions”ofdim ensionalsynthesis for rigid body guidance. An exam ple is given to illustrate the efficiency and advantage of this m ethod.