Slack and Excessive Loading Avoidance in n-Tendon Continuum Robots

In this work, two tendon tension loading distributions (fixed and moving) are designed to prevent undesired slack and excessive loading in tendons of continuum manipulators. For any given beam configuration, the algorithms utilize the proposed loading distributions to find a new beam configuration as well as base displacement to control the orientation or position of the n-tendon continuum robot. The algorithms account for the bending and axial compliance of the manipulator as well as tendon compliance. Numerical results are provided to demonstrate the orientation and position control algorithms under fixed or moving loading distributions. A 6-tendon continuum robot system is employed to experimentally evaluate the effectiveness and accuracy of the proposed control algorithms. Multiple experiments are carried out and results are reported. The results verify the performance of the proposed control algorithms in avoiding slack and excessive loading in tendons and controlling the orientation and position of continuum structures.