Theory and experiments to understand a contact between two filaments

The orthogonal clasp © 2021 EPFL - Mechanical engineers and mathematicians at EPFL have joined forces to gain a better understanding of the geometry and mechanics of two filaments in contact - as in the cases of knots and woven fabrics. Pedro Reis, head of EPFL's Flexible Structures Laboratory, and John Maddocks, head of EPFL's Laboratory for Computation and Visualization in Mathematics and Mechanics, have something in common: a fascination with ropes and knots. Reis, an engineer, is an avid rock climber while Maddocks, a mathematician, has a passion for sailing. But their mutual interest in knots is not restricted to their hobbies, as knots are used in a variety of applications - take surgical sutures, for example. And although knots have been part of our daily lives since the dawn of time, their mechanics are still poorly understood. A simplified knot Reis, Maddocks and the researchers at their labs have been studying a specific configuration of contact between two filaments - the orthogonal clasp - which can be regarded as the most basic building block for every knot. "This intertwining is the simplest of all knots; or to be more specific, it's the link that knots are based on.