A cross-helical tendons actuated dexterous continuum manipulator

S shape dexterous continuum manipulators (DCMs) are preferred in minimally invasive surgeries for better steerability towards a target and obstacles avoidance capability. Current ways of realizing S shapes need to combine multi-bending segments which need to control the different segment separately. We propose a cross-helical tendons actuated DCM that can realize S shapes just using one segment. With two pairs of cross-helical tendons, it can realize omin-directional S shapes, where two types of planar S shapes are investigated in this paper. A prototype with 8mm diameter and 80mm length is built and the kinematics characteristics are investigated. The results show it can well realize the desired S shapes. The tip directional capability and obstacles avoidance capability are compared with C shape DCM.