Flexible articulate surgical tool

A flexible elongate shaft assembly which includes an elongate flexible tube having at least one joint built into the elongate flexible tube, and the at least one joint comprised of at least one notch. Each notch includes a contact-aided compliant notch topology built into the elongate flexible shaft configured to cause each notch to mechanically interfere with itself and self-reinforce during bending of each notch resulting in an increase in stiffness of each notch to prevent buckling and plastic deformation of the elongate flexible shaft assembly, and assume a predetermined and designed bending shape of the elongate flexible shaft assembly. The flexible elongate shaft assembly is incorporated into a flexible articulate surgical tool that provides the needed stiffness in order to be able to manipulate tissue and bear loads in anatomically confined spaces. The surgical tool includes a clinician operated handle, the flexible elongated shaft assembly extending from the handle to a surgical tool with the flexible elongate tube having one or more joint sections located near the surgical tool. A flexible cable connects the handle to the surgical tool. The joint sections are configured so that when the clinician activates the surgical tool, a mechanical interference is generated in each of the notches and this mechanical interference not only increases stiffness throughout the articulation of the notch's range-of-motion but it also serves the dual purpose of controlling the bent "shape" of the flexible portion of the notch.