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Concentric tube robots (CTRs) have drawn significant research attention over the years, particularly due to their applications in minimally invasive surgery (MIS). Indeed, their small size, flexibility, and high dexterity enable several potential benefits for MIS. Research has led to an increasing number of discoveries and scientific breakthroughs in CTR design, fabrication, control, and applications. Numerous prototypes have emerged from different research groups, each with their own design and specifications. This survey paper provides an overview of the state-of-the-art of the mechatronics aspects of CTRs, including approaches for the design and fabrication of the tubes, actuation unit, and end effector. In addition to the various hardware and associated fabrication methods, we propose to the research community, a unifying way of classifying CTRs based on their actuation unit architecture, as well as a set of specification details for evaluation of future CTR prototypes. Finally, we also aim to highlight the current advancements, challenges, and perspectives of CTR design and fabrication.
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Enabling Higher Performance Concentric Tube Robots Via Multiple Constant-Curvature Tubes
Concentric tube robots (CTRs) consist of a set of telescoping, pre-curved tubes, whose overall shape can be actively controlled by translating and rotating the tubes with respect to each other. The majority of CTRs to date consist of piecewise constant-curvature tubes, with a straight section followed by a single constant-curvature section. Several approaches have been proposed for CTR designs that can lead to improvements in metrics such as the workspace, orientability, dexterity, and stability. Here we propose to use CTRs with multiple constant-curvature sections. We perform two simulation studies that compare the performance of the multiple constant- curvature CTRs with standard single constant-curvature tubes. We also demonstrate how using one of the proposed multiple constant-curvature designs can enable the reduction in the number of tubes needed to achieve the same performance as a standard three-tube CTR.
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- Award ID(s):
- 2146095
- PAR ID:
- 10402472
- Date Published:
- Journal Name:
- International Symposium on Medical Robotics
- ISSN:
- 2771-9049
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Accepted Manuscript1.0
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- The DOI is not currently available.
