UC Irvine

This paper presents a design system for planar eight-bar linkages that begins with a user specified 6R planar loop and five required configurations, and computes two RR constraints that yield an eight-bar linkage. There are 32 ways that these constraints can be added to the 6R loop to yield as many as 340 different linkages, which include eight of the 16 eight-bar linkage topologies. An analysis routine based on the Dixon determinant is used to verify the performance of each design candidate. Random variation of task configurations within user specified tolerance zones is used to increase the number of candidate designs. The result is an effective system for the design of eight-bar linkages, which is demonstrated by designing linkages that guide movement though a symmetric and offset set of parallel task positions along a straight line.