Dual-Triangular Remote Centre of Motion Mechanism With Cable Transmission

Shao Liu (1) , Binbin Chen (1) , Stéphane Caro (2, 3, 4) , Sébastien Briot (5) , Chao Chen (1)

1 Monash University [Clayton]
2 CNRS - Centre National de la Recherche Scientifique
3 LS2N - Laboratoire des Sciences du Numérique de Nantes
4 LS2N - équipe RoMas - Robots and Machines for Manufacturing, Society and Services
5 IRCCyN - Institut de Recherche en Communications et en Cybernétique de Nantes

The remote centre of motion (RCM) mechanisms are increasingly used to develop robotic surgical systems. Currently, parallelogram-based planar RCM mechanism are often combined with single revolute joint to deliver the two degrees of freedom (DOFs) required in the minimally-invasive surgical applications. However, parallelogram-based planar RCM mechanisms encounter issues associated with device footprint, which compromise optimal surgical functioning. The dual-triangular linkage (DT-linkage) with RCM is proposed in the attempt to replace the parallelogram-based linkage and resolve the footprint issue. This paper presents the work on the design and static analysis of cable-based auxiliary mechanism for DT-linkage. The aim is to achieve backlash-free and singularity-free mechanical constraint, such that the ROM of the original DT-linkage can be doubled without expanding the device footprint. A constraint approach is conducted to solve for the force within the cable sections. The analytical solution at singular configuration indicates tension in all cable sections hence proved the functioning of the cable constraint. By utilising the QR decomposition, the numerical solution of minimum required cable stiffness is also calculated from the constraint approach.

Domains: Robotics [cs.RO]

Shao Liu, Binbin Chen, Stéphane Caro, Sébastien Briot, Chao Chen. Dual-Triangular Remote Centre of Motion Mechanism With Cable Transmission. 4th Joint International Conference on Multibody System Dynamics (IMSD2016), May 2016, Montréal, Canada. ⟨hal-01285928⟩