Cognate connections and their application to function cognates and overconstrained linkages

A simple short cut to finding some of the function cognates of a spatial spatial single-loop linkage is as follows. Replace the floating connection between the input and outputlinks by a cognate connection without disturbing the geometry of the input, output and fixed links. The cognates of the -CRoC-, -CRC-, -RRS-, -RRE- and -PRS- connections are systematically obtained. These are then shown applied to the derivation of some function cognates of five-bar mechanisms such as RCRCR, RSRRR, etc. and some four-bar mechanisms. They can further be used as redundant connections to improve force transmission. Almost all the overconstrained four-bars with a connectivity sum of 6 are also derived from these cognate connections. © 1985.