Algebraieally expressing the derivatives of the transmission-ratio of the four-bar into the inverse of the tangents of the so-called cOllineation-angles, enables the grounding of an entirely new approach to 3rd order instantaneous kinematies. As aresuIt, the Carter-Hall circle appeared as a handy tooi for local function-generation by four-bar linkages. AIso, a new, short design for Ball's point came out, being convenient for the composition of approximate straight-line mechanisms. The new approach also produced two completely different four-bar types, possessing an approximate constant transmission-ratio. Freudenstein's formula, embedded in this theory, further allowed the derivation of the curvatures of the crank-polodes resulting into the possibility to replace gear-wheels. The replacing of the cycloidal motion by a four-bar on which Roberts'Law was applied, produced two different four-bar solutions, ha ving a nearly uniformly moving coupier point along an approximate straight-stretch of its path.
|Title of host publication||3rd international workshop on advances in robot kinematics, September 7-9, 1992, Ferrara, Italy|
|Publication status||Published - 1992|