Determination of Noncontributing Forces and Noncontributing Impulses in Three-Phase Motions

Abstract

Numerous dynamical systems undergo, while in motion, imposition and/or removal of constraints. Three phases of motion are involved: a phase during which the motion is defined as unconstrained, a phase during which the motion is defined as constrained, and an intermediate, transition phase, when constraints are imposed or removed. Noncontributing forces (sometimes called nonworking, reaction forces), and noncontributing impulses, namely, impulses associated with noncontributing forces in the transition phase, play a central role in the mechanics of systems undergoing such motions, and are the subject matter of the present paper. Specifically, a six-step procedure is introduced for the determination of noncontributing forces and of noncontributing impulses throughout three phase motions.