A novel continuum robotic cable aimed at applications in space

We introduce a new class of long and thin continuum robots intended for use in space applications. This 'cable' robot is a next-generation version of the current state of the art (NASA's 'Tendril'). The article describes the key practical limitations of the mechanical design of 'Tendril'. We introduce the design specifics of our novel concept for a next-generation device with significantly enhanced performance. Equipped with a light and compact motor-encoder actuation mechanism, the new design has improved compliance and possesses a concentric backbone arrangement which is tendon-actuated and spring-loaded. A new forward kinematic model is developed extending the established models for constant-curvature continuum robots, to account for the new design feature of controllable compression (in the hardware). The model is validated by performing experiments with a three-section prototype of the design. The new model is found to be effective as a baseline to predict the performance of such long and thin continuum 'cable' robots.