Design Considerations for Rapidly Deployable, Soft Robotic Catheter Tip

Abstract

Soft robots offer inherent compliance and enhanced safety and adaptability to the environment. Certain designs can also be low cost and easy to fabricate. For these reasons, there has been a recent boom in soft robotics research. Despite these advantages, these robots present challenges in terms of modeling and design. In particular, some of the manufacturing processes for these devices introduce geometric and material uncertainties that can complicate the design and control of these devices. This thesis explores a subset of soft robots actuated by tendons and addresses some of these challenges within the context of potential applications for enhancing navigation during mechanical thrombectomy by adapting passive catheters with distal tip steerability. A unique modal calibration model was developed from a static Cosserat rod model. Calibrating the Cosserat rod model allowed computations to occur orders of magnitude quicker, and noise to be minimized. Both attributes improved design optimization by increasing robustness of the multi-level model and allowed for the timely exploration of the parameter solution space. Sensitivity minimization was applied to the design optimization of the soft robot. By using Cosserat rod mechanics modeling to calibrate the modal coefficients, we created a rapid design optimization framework that drastically enhanced the feasibility and speed of design optimization for these devices.