Parasitic Inclinations in Cable-Driven Parallel Robots using Cable Loops

Saman Lessanibahri (1, 2, 3) , Philippe Cardou (4, 5) , Stéphane Caro (2, 6, 3)

1 ECN - École Centrale de Nantes
2 LS2N - Laboratoire des Sciences du Numérique de Nantes
3 LS2N - équipe RoMas - Robots and Machines for Manufacturing, Society and Services
4 Laboratoire de robotique
5 ULaval - Université Laval [Québec]
6 CNRS - Centre National de la Recherche Scientifique

Cable-Driven Parallel Robots (CDPRs) also noted as wire-driven robots are parallel manipulators with flexible cables instead of rigid links.A CDPR consists in a base frame, a Moving-Platform (MP) and a set of cables connecting in parallel the MP to the base frame. CDPRs arewell-known for their advantages over the classical parallel robots in terms of large workspace, reconfigurability, large payload capacity andhigh dynamic performance. In spite of all the mentioned advantages, one of the main shortcomings of the CDPRs is their limited orientationworkspace. The latter drawback is mainly due to cable interferences and collisions between cables and surrounding environment. Hence, a planarfour-Degree-of-Freedom (DoF) under-constrained CDPR with an articulated MP is introduced and studied in this paper. The end-effector isarticulated through a cable loop, which enables the robot toobtain a modular pose determination, namely orientation and positioning. As a result,the mechanism under study has an unlimited and singularity-free orientation workspace in addition to a large translational workspace. It should be noted that some un wanted rotational motions of the moving platform, namely, parasitic inclinations, arise due to the cable loop. Finally, those parasitic inclinations are modeled and assessed for the mechanism at hand

Mots clés: Large Workspace; Cable-Driven Parallel Robots; Cable Loop; Kinematics

Domaines: Génie mécanique [physics.class-ph]; Automatique / Robotique

Saman Lessanibahri, Philippe Cardou, Stéphane Caro. Parasitic Inclinations in Cable-Driven Parallel Robots using Cable Loops. Procedia CIRP, 2018, 70, pp.296-301. ⟨10.1016/j.procir.2018.02.013⟩. ⟨hal-02405653⟩