Concentric tube robots (CTRs) are well-suited to address the challenges of minimally invasive surgical procedures due to their small size and ability to navigate highly constrained environments. However, uncertainties in the manufacturing process can lead to challenges in the transition from simulated designs to physical robots, particularly for CTRs operating in small, hard-to-reach surgical spaces, such as micro-laryngeal surgery.
In this work, we propose an end-to-end design workflow for CTRs that considers the often-overlooked impact of manufacturing uncertainty, focusing on two primary sources — tube curvature and diameter. This comprehensive approach incorporates a two-step design optimization and an uncertainty-based selection of manufacturing tolerances that aim to balance the cost and the robot performance. Simulation results highlight the substantial influence of manufacturing uncertainties, particularly tube curvature, on the physical robot’s performance. By integrating these uncertainties into the design process, we can effectively bridge the gap between simulation and real-world performance.
Two hardware experiments validated the proposed CTR design workflow. The first experiment confirmed that the performance of the physical robot was within the simulated probability distribution from the optimization, while the second experiment demonstrated the feasibility of the first dual-CTR system for use in micro-laryngeal surgical tasks. This work not only contributes to a more comprehensive understanding of CTR design by addressing manufacturing uncertainties, but also creates a new framework for robust design, as illustrated in the context of micro-laryngeal surgery.