Kinematically indeterminate linkages are those whose complete set of instant centers cannot be obtained by Kennedy’s theorem. A linkage of this kind is often characterized as having no four-bar loop, or even if one exists, it does not lead to the finding of all other instant centers in the multiple-loop chain. This paper presents a simple graphical method for dealing with many of these linkages. While not altering the total degrees of freedom of the linkage, a virtual cam is introduced to help locate some key instant centers. This method also lends itself to applications along with Pennock’s method to achieve greater usability.

Issue Section:
Mechanisms and Robotics
Keywords:
cams (mechanical), couplings, mechanical engineering computing
Topics:
Linkages, Theorems (Mathematics), Kinematics
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Copyright © 2008
 by American Society of Mechanical Engineers
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