A Continuum Robot With Programmable Tendon Routing for Desired Curve Generation

Continuum robots are widely employed in confined environments with narrow passages and spatial constraints. However, achieving general curves with non-constant curvature remains challenging, as existing systems typically rely on multiple flexible segments arranged in series, coupled with complex drive systems requiring numerous actuators. This paper proposes a novel continuum robot design that features a programmable tendon routing capable of generating desired curves. The system integrates modular joints and a single-actuator drive unit, enabling the generation of spatial curves with non-constant curvature. By strategically designing the arrangement of modular joints to control rotational direction and angular deflection at each joint, the system achieves a substantially expanded design workspace compared to conventional continuum robots. Simulation and prototype experiments validate the proposed design methodology. The relative mean distance between simulated and desired curve remains below 3.12$\%$, while the prototype demonstrates a relative mean distance of 6.67$\%$from the desired curve. This approach offers a promising pathway to advance continuum robot design by improving configurational adaptability while simultaneously achieving complex curve generation and reduced drive system complexity.