5 Years of Research on Extensible Tendon-driven Continuum Robots

We have been working on dextrous extensible tendon-driven continuum robots since 2014. After 3 prototype iterations, a patent, conference and workshop papers based on various student contributions, we are proud to see this summarizing paper being published in the International Journal of Robotics Research!

With 7 mm diameter, this is one of the smallest, if not the smallest, extensible tendon-driven continuum robot worldwide. The initial idea to utilize magnets at alternating polarity orientation embedded into the spacer disks came a long way. The magnetic repulsion of the disks enables their equidistant spacing for any segment length and ensures good bending behaviour.

Thanks to extensible segments our robot is able to traverse curvilinear path in a follow-the-leader fashion, i.e. the shaft follows the course of the tip. This is particularly useful for applications in tortuous environments such as nondestructive inspection and maintenance or minimally invasive surgery.

Many contributed to the realization of this novel continuum robot! First and foremost it was Thien-Dang Nguyen who came up with the idea of magnetic spacer disks during his bachelor's' research thesis. Together with Ernar Amanov, they took the idea from an initial proof-of-concept to a sophisticated prototype which served CRL as a great demonstrator for several years now! Maria Neumann came up with a mechanics-based model and investigated the follow-the-leader motion capabilities theoretically. Taha Chikhaoui, Sven Lilge, and Simon Kleinschmidt investigated different modelling approaches for extensible continuum robots. And lastly, it was the effort and dedication of Ernar Amanov who took the robot on as a side project to his dissertation and took it to the next level proving that our theoretical results actually work on the real robot! Thank you everyone! I couldn't be more proud of a five years research endeavour!