Active | C. Girerd

Multi-backbone Continuum Robots

Fri, 12 Sep 2025 00:00:00 +0000

Navigating tortuous anatomical pathways, such as the aortic arch, requires continuum robots capable of complex three-dimensional deformations. Existing designs are often limited to specific curve families, and extending their shape capabilities usually increases mechanical complexity and system size. In this paper, we present a novel hybrid continuum robot that combines a multi-backbone structure with a flexible notched tube. Control rods enable bending, compression, and extension, while the tube’s structural modifications induce torsion along the backbone. This allows the robot to achieve both planar and helical shapes in a compact form factor.

Publications

Camille Benoist, Cédric Girerd, Carlo Saija, Nabil Zemiti, Philippe Poignet, Pierre Berthey-Rayne (2026). A Concentric Multi-Backbone Robot for Transaortic Mitral Valve Access. In IROS.

PDF Video

Camille Benoist, Cédric Girerd, Carlo Saija, Nabil Zemiti, Philippe Poignet, Pierre Berthey-Rayne (2026). Helical and Planar Continuum Robot Shapes by Structural Tube Modifications and Backbone Length Control. RA-L.

PDF Video DOI

Camille Benoist, Cédric Girerd, Nabil Zemiti, Philippe Poignet, Pierre Berthey-Rayne (2024). Tendon-Driven vs Rod-Driven Continuum Robots: A Bench Test Evaluation. In CRAS.

PDF

Vine Growing Robots

Fri, 12 Sep 2025 00:00:00 +0000

A new subclass of soft robot, known as tip-extending or “vine” robots, consists of long inflatable devices that move through the environment by extending from the tip. A key requirement for many applications of these robots is a working channel - a hollow tube through the core of the robot for passing tools, sensors, fluids, etc. While working channels have been proposed in a few vine robots, it remains an open challenge to create miniaturized vine robots (diameter < 1 cm) with working channels that enable continuous access through the core. In this paper, we analyze the growth models of current vine robot designs and show that the working channel greatly increases required pressure to grow at small scales due to internal friction. Based on this insight, we propose the concept of storing scrunched material at the tip of the vine robot to circumvent this frictional force. We validate our models and demonstrate this concept via prototypes down to diameters of 2.3 mm. Overall, this work enables the creation of miniaturized vine robots with working channels, which significantly enhances their practicality and potential for impact in applications such as minimally invasive surgery.

Publications

Shamsa Al Harthy, S.M.Hadi Sadati, Cédric Girerd, Sukjun Kim, Alessio Mondini, Zicong Wu, Brandon Saldarriaga, Carlo A. Seneci, Barbara Mazzolai, Tania K. Morimoto, Christos Bergeles (2025). Tip-Growing Robots: Design, Theory, Application. TRO.

PDF Dataset DOI

Ayush Giri, Cédric Girerd, Jacobo Cervera-Torralba, Michael T. Tolley, Tania K. Morimoto (2025). InchIGRAB: An Inchworm-Inspired Guided Retraction and Bending Device for Vine Robots During Colonoscopy. TMECH.

PDF DOI

Cédric Girerd, Anna Alvarez, Elliot W. Hawkes, Tania K. Morimoto (2024). Material Scrunching Enables Working Channels in Miniaturized Vine-Inspired Robots. TRO.

PDF Video DOI

Compact Continuum Robots

Fri, 25 Dec 2020 00:00:00 +0000

The standard-of-care involves a range of affordable, manual, hand-held rigid tools, with limited dexterity. In contrast, roboticized tools with increased accessibility and dexterity are usually larger, heavier, grounded devices that are teleoperated, posing a new set of challenges. To bridge the gap between those classes of devices, we propose a hand-held concentric tube robot that has the dexterity and precision of large roboticized devices, while maintaining the footprint of a traditional hand-held tool.

Publications

Chibundo Nwafor, Cédric Girerd, Guillaume J. Laurent, Tania K. Morimoto, Kanty Rabenorosoa (2023). Design and Fabrication of Concentric Tube Robots: A Survey. TRO.

PDF Dataset DOI

Cédric Girerd, Tania K. Morimoto (2020). Design and Control of a Hand-Held Concentric Tube Robot for Minimally Invasive Surgery. TRO.

PDF Video DOI