Influence of Antagonistic Tensions on Distributed Friction Forces of Multisegment Tendon-Driven Continuum Manipulators With Irregular Geometry

In this article, we thoroughly analyze the effect of the single-tendon and antagonistic tendons actuation on the tension loss of multisegment tendon-driven continuum manipulators (TD-CMs) with irregular geometry. To this end, we propose a generic analytical modeling approach and an iterative algorithm that can solve the unknown correlation between the distributed friction force, tendons' tension transmission loss, and planar deformation behavior of TD-CMs during tendons' pulling and releasing phases. The proposed generic model solely relies on known input tendons' tensions and does not require a priori knowledge of the manipulator's shape and/or other experimental conditions. To investigate the influence of the actuation type on the tension loss and deformation behavior of TD-CMs, we fabricated two different TD-CMs and performed various simulation and experimental studies with the single-tendon and antagonistic tensions actuation. The obtained results indicate the importance of considering the effect of the distributed friction force and actuation type on the tension(s) loss of multisegment TD-CMs. Moreover, it clearly demonstrates the efficacy and accuracy of the proposed model in providing insights and understanding of tension transmission process in various types of actuations in multisegment TD-CMs with irregular geometry.