Workspace analysis of realistic elbow and dual-elbow robot manipulators

Abstract

The geometry of the robotic structure directly influences the positional and orientational capabilities of a manipulator. Among the existing robot geometries, the ideal elbow and dual-elbow manipulators are known to provide the maximum reachable and dextrous workspaces for a given total link length. Despite the fact that the ideal dual-elbow manipulators share the basic properties of the ideal-elbow manipulators, they have received scant attention in the literature. In a companion paper [Mech. Mach. Theory28, 357–373 (1993)], the ideal elbow and dual-elbow geometries have been thoroughly studied. In this paper, realistic elbow and dual-elbow geometries, incorporating designed deviations from the ideal case and unavoidable manufacturing errors, are considered. It is shown that practical dual-elbow robots are superior in terms of reachability and dexterity, especially for applications that require a relatively small tool length. Un modèle kinematique est indispensable pour la conception et l'analyse du comportement des robots manipulateurs. Il est alors necessaire d'etablir un modèle qui décrive correctement le mouvement d'un systeme réaliste. Dans cette communication on propose un modèle nouveau pour analyser efficacement l'influence des variations de paramètres géométriques sur la zone de travail des manipulateurs “coude” et “coude-duel”. Les resultats indiquent la superiorité de l'articulation “coude-duel” pour tâches demandant de outil court.