150-year unified mobility formula issue
Yanwen Li · Journal of Yanshan University · 2011
The mechanism unified-mobility-formula issue has experienced over 150 years.In the beginning of this paper,it introduces the development of the mobility issue,and the Puzzle or Paradoxical mechanisms which do not suit the mobility G-K Criterion,and those scholars who studied the issue and proposed theirs formulas and methods,and also analyzed the characteristics of those methods.Then,the paper introduces the abnormal classical and mordern parallel mechanisms collected by Gogu,which is named as mechanism-mobility GG Issue.In the second part,the paper focuses on the new mobility principel and the Modified G-K Criterion,based on reciprocal screw proposed by Huang and his students.It introduces the research process and characteristic of the method.It analyzes how to demonstrate the method to be uniform and universal by using all the examples in GG Issue and which denotes the method has great power for solution mobility issue and is suitable the mordern multi-DOF,overconstraint,even muliloop-coupling mechasms.All above-mention indecates that they has solved the 150-year issue.