• CN:11-2187/TH
  • ISSN:0577-6686

›› 1957, Vol. 5 ›› Issue (3): 263-274.

• 论文 • 上一篇    下一篇

四杆机构运动误差的一个解法

曹惟庆   

  1. 清华大学
  • 发布日期:1957-06-01

A METHOD FOR DETERMINING THE KINEMATIC ERRORS OF FOUR-BAR LINKAGES

TSAO WEI-CHING   

  1. Tsing Hua University
  • Published:1957-06-01

Abstract: The errors of velocity and acceleration due to the inaccuracy of the length of bars may be determined by considering the diagram of the mechanism as composed of closed vector polygon. The derivative of the bar vector equation makes another closed vector polygon which represents the displacement errors of it, and again differentiating it once and twice with respect to the time, we find the vectors of velocity and acceleration errors. For illustrating this method two numerical examples are treated, one of which gives the curves of errors calculated for one cycle of motion of the mechanism. It is interesting that a range of nearly constant position error of output crank is obtained, and the other is considered as it may be useful for the design of computing mechanisms. This method calls the result that we may find the absolute values of errors of bars by no means of the relative values of errors of each of the other bars with respect to the calculated one, and on the contrary we may find the relative value of errors by means of the corresponding closed vector polygon.