Thesis (M.A.S.)--University of Toronto (Canada), 2019
Includes bibliographical references
Recent studies on concentric tube robots (CTRs) have shown that they are well-suited for minimally invasive surgeries. However, typical surgical procedures require the use of multiple tools simultaneously which has led to the development of dual-arm CTRs that are susceptible to self-collision. In this research, a real-time closed-loop control system for dual-arm CTRs is proposed which detects and avoids inter-collision between arms along their entire body. The proposed controller is developed with three prioritized tasks; physical constraints, self-collision avoidance, and end-effector tracking. To avoid self-collision, the minimum distance between the manipulators in the Cartesian space is kept at a pre-set threshold. The experimental results demonstrated the efficacy of the controller in handling self-collision to reach 97.69% of all possible pairs of points in the overlapping workspace of two arms. Further, the maximum RMS tip position error in collision cases, 0.278 mm, was less than 1% of the total robot's length
Electronic reproduction. Ann Arbor, Mich. : ProQuest, 2020
