Dual-Segment Continuum Robot With Continuous Rotational Motion Along the Deformable Backbone

The hyper redundancy and flexibility of continuum robots have made them attractive to replace conventional rigid-link robots in many applications. Although the robot body can be bent to different directions as needed, rotation along the backbone is not a feature available in many continuum robot designs. In this article, we propose a pneumatic-driven, dual-segment continuum robot with the capability of providing continuous rotation along the deformed backbone (CRADB) at a particular point. A slip ring was employed to enable rapid coupling/decoupling between the air supply and different chambers of the robot, while a stepper motor with adjustable speed was adopted to provide the additional rotational motion. A novel control scheme based on optimization was developed to compute the required shape configuration under different modes. Control schemes toward fast deformation motion and CRADB motion have been, respectively, built. Experiments were conducted to compare the performance in positioning the robot’s tip with and without the additional degree of freedom. The ability to enable continuous rotation after positioning at different points was also tested to demonstrate its performance in various potential applications.