A Task Driven Unified Synthesis of Planar Four Bar and Six Bar Linkages With R and P Joints for Five Position Realization

Abstract

This paper deals with the problem of integrated joint type and dimensional synthesis of planar fourbar and sixbar linkages, which could contain both revolute (R) and prismatic (P) joints, for guiding through five specified task positions of the endeffector. In a recent work, we developed a simple algorithm for analyzing a set of given task positions to determine all feasible planar dyads with revolute and/or prismatic joints that can be used to guide through the given positions. This paper extends this algorithm to the integrated joint type and dimensional synthesis of Watt I and II and Stephenson I, II, and III sixbar linkages that contain both Rand Pjoints. In the process, we developed a new classification for planar sixbar linkages according to whether the endeffector can be constrained by two dyads (type I), one dyad (type II), or no dyad (type III). In the end, we demonstrate this taskdriven synthesis approach with three examples including a novel sixbar linkage for lifting an individual with age disability from seating position to standing position.