A Design System for Six Bar Linkages Integrated With a Solid Modeler

Abstract

This paper presents a design system for planar and spherical sixbar linkages, which is integrated with a solid modeler. The user specifies a backbone 3R chain in five task configurations in the sketch mode of the solid modeler and executes the design system. Two RR constraints are computed, which constrain the 3R chain to a single degreeoffreedom sixbar linkage. There are six ways that these constraints can be added to the 3R serial chain to yield as many as 63 different linkages in case of planar sixbar linkages and 165 in case of spherical sixbar linkages. The performance of each candidate is analyzed, and those that meet the required task are presented to the designer for selection. The design algorithm is run iteratively with random variations applied to the task configurations within userspecified tolerance zones, to increase the number of candidate designs. The output is a solid model of the sixbar linkage. Examples are presented, which demonstrate the effectiveness of this strategy for both planar and spherical linkages.