Getting from a 3D, dexterous, single-port workspace to a one-segment continuum robot ☆

Given the limited availability of off-the-shelf continuum robots (CRs), researchers and engineers must design their own and tailor them to their specific use case requirements. Questions such as the following arise: What is the minimum length of the CR needed to achieve the desired dexterous workspace? And where should the robot be ideally located with respect to the workspace? These questions are answered for a single-port setup in this paper. A projection-based method is introduced that maps the dimensionality of the required workspace from 3D to 1D, exploiting the remaining degrees of freedom preserved in a single-port procedure. Then, a set of equations for the most critical point in the workspace is described, representing the geometry of both the CR and the workspace. A bounded, non-linear optimization approach is implemented, computing the global minimum of this set of equations. This method is simulated and tested for a length-extensible, multi-backbone CR. To the best of the authors' knowledge, this is the first time a desired dexterous workspace has been empirically verified for a CR. Furthermore, the prototype features novel design elements that solve relevant mechanical challenges in the state-of-the-art