Slack Dynamics on an Unfurling String

TL;DR

This paper models how slack in a thin string grows and moves when the string rapidly unfurls on a rigid surface, combining qualitative analysis with numerical validation.

Contribution

It introduces a new qualitative model for slack dynamics in an unfurling string, highlighting mechanisms of amplification, rectification, and advection under steady stress.

Findings

Validated assumptions with numerical experiments

Identified mechanisms of slack amplification and rectification

Posed new questions on spatial motions of thin objects

Abstract

An arch will grow on a rapidly deployed thin string in contact with a rigid plane. We present a qualitative model for the growing structure involving the amplification, rectification, and advection of slack in the presence of a steady stress field, validate our assumptions with numerical experiments, and pose new questions about the spatially developing motions of thin objects.