Non-probabilistic kinematic reliability analysis of planar mechanisms with non-uniform revolute clearance joints

Abstract

Owing to the inevitable phenomena in which the wear of a revolute joint is non-uniform and severely affects the output motion accuracy, a conservative and efficient motion accuracy evaluation of mechanisms considering non-uniform wear is required by designers. Hence, this paper presents an integrated non-probabilistic kinematic analysis of precision mechanisms with non-uniform wear in joint by combining multi-body dynamic analysis, wear prediction and kinematic reliability analysis. The presented accuracy measurement and corresponding solution strategy can be used as the objective or constraint in dimensional synthesis to realise a longer service life. The non-uniform clearance is quantified by unknown but bounded variables, the boundary of which is expressed by the B-spline function. Furthermore, the kinematic reliability is calculated based on the non-probabilistic interval interference model. Two numerical examples consisting of wear prediction, motion error quantification, and reliability evaluation are presented to demonstrate the validity and applicability of the developed methodology.