KnotDLO: Toward Interpretable Knot Tying

TL;DR

KnotDLO is a novel method for one-handed deformable linear object knot tying that is robust, interpretable, and does not require training, achieving a 50% success rate in unseen configurations.

Contribution

This work introduces KnotDLO, a new approach for interpretable, training-free knot tying of deformable objects that plans grasp and target waypoints from shape analysis.

Findings

Achieves 50% success rate in tying overhand knots from unseen configurations.

Robust to occlusion and varying initial rope states.

Decouples visual reasoning from control for reliable performance.

Abstract

This work presents KnotDLO, a method for one-handed Deformable Linear Object (DLO) knot tying that is robust to occlusion, repeatable for varying rope initial configurations, interpretable for generating motion policies, and requires no human demonstrations or training. 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. KnotDLO computes intermediate waypoints from the geometry of the current DLO state and the desired next state. 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.