KnotDLO: Toward Interpretable Knot Tying

Holly Dinkel, Raghavendra Navaratna, Jingyi Xiang, Brian Coltin, Trey Smith, Tim Bretl

Keywords: knot tying, manipulation, deformable linear objects

TL;DR: This work presents KnotDLO, a method for one-handed knot manipulation to transform a Deformable Linear Object (DLO) into knot states that achieves a 50% success rate.

Abstract: This work presents KnotDLO, a method for one-handed knot manipulation to transform a Deformable Linear Object (DLO) into knot states. Grasp and target waypoints for future DLO states are planned from the current DLO shape. Grasp poses are computed from indexing the tracked piecewise linear curve representing the DLO state based on the current curve shape and are piecewise continuous. Intermediate waypoints are computed from the geometry of the current DLO state and the desired next state. The perception and manipulation system is robust to occlusion, repeatable for varying rope initial configurations, interpretable for generating motion policies, and requires no human demonstrations or training. The system decouples visual reasoning from control. In 16 trials of knot tying, KnotDLO achieves a 50% success rate in tying an overhand knot from previously unseen configurations.

Submission Number: 25