Kinematic structure of mechanisms: a bond graph approach

Abstract

It is proposed to use the bond graph framework for performing the type synthesis of mechanisms. Starting from the standard bond graph modelling approaches of rigid multibody systems, two word bond graph representations of kinematic structures are defined. They are considered as simple junction structures describing the interconnection topology of mechanisms. The first includes BODY multiports, and the second LOOP multiports as junction elements. Then how the assignment of causality at a word bond graph level displays the topological properties of mechanisms is discussed. Non-local causal constraints are introduced within the causality assignment procedure that take into account the topological properties of kinematic subchains or dependent kinematic loops. Finally, some basic interpretations of causality concepts in terms of the mobility properties of mechanisms and kinematic chains are given, which deal with the main topological analysis problems involved in the type synthesis of mechanisms.