Date of Award
Master of Science in Mechanical Engineering - (M.S.)
R. S. Sodhi
Ian Sanford Fischer
An infinite number of planar four-bar mechanism solutions exist for a series of prescribed rigid-body positions. Given a set of Burmester curves or numerically-generated fixed and moving pivot curves, sorting through the limitless number of possible mechanism solutions to find one that ensures full link rotatibility, satisfies compactness criteria and produces feasible transmission angles can be a daunting task. In this work, two algorithms are developed and presented by which the user can select optimum planar four-bar motion generators (optimum with respect to Grashof criteria, mechanism perimeter criteria and transmission angle criteria) from a set of all mechanism solutions produced by through either Burmester curves or numerically-generated fixed and moving curves. Both the Burmester curve-based method and the numerical fixed and moving pivot curve-based method have been codified in MathCAD to support advanced analysis capabilities. The examples in this work demonstrate the synthesis of optimum Grashof crank-rocker, drag link, double-rocker and triple-rocker motion generators.
Martin, Peter J., "Burmester curve and numerical motion generation of Grashof mechanisms with perimeter and transmission angle optimization in MathCAD" (2007). Theses. 382.