ABSTRACT
This paper is a survey of our research on kinematic tolerance analysis of mechanical systems with paramet ric part tolerances. We present a general algorithm for planar systems and illustrate it with a design case study. The algorithm constructs a variation model for the system, derives worst-case bounds on the variation, and helps designers find unexpected failure modes, such as jamming and blocking. The variation model is a gen eralization of the configuration space representation of nominal part contacts. The algorithm handles general planar systems of curved parts with contact changes, including open and closed kinematic chains. It con structs a variation model for each interacting pair of parts then derives the overall system variation at a given configuration by composing the pairwise variation models via sensitivity analysis and linear programming. We demonstrate the algorithm on a gear selector mech anism in an automotive transmission with 100 func tional parameters. The analysis, which takes less than a minute on a workstation, indicates that the critical kinematic variation occurs in third gear and identifies the parameters that cause the variation.
