How to Tie Wood Knots

Date

2023

Authors

Zarate, Ri

Journal Title

Journal ISSN

Volume Title

Publisher

University of Oregon

Abstract

Woods anisotropic nature causes “defects” in lumber creating unwanted curvature. Actuation is activated by fluctuating moisture content within the wood cells making a shrinking and swelling motion (Hoadly 73-90). Laminating two perpendicular layers of wood veneer, one dry (passive) and one with high moisture (active), creates predictable, strong, and scalable self-actuating curvature without additional energy input (fig 1) (Rüggeberg 4-9, Timoshenko 235). Programable actuation is well studied (Vailati 11-12, Tahouni 13), but knots are particularly difficult to choreograph due to the formal combination of bending and torsion (Bhattacharyya 3-4). This study sought to create a self tying veneer knot by honing 2D geometry to laser cut prior to shaping (fig 2a, 2b). Speed was found to be controllable by varying width of bilayers resulting in several wood knots. Increasing elasticity of the veneer in its final curved form opens possibilities for improving material performance by using woods ingrained “physical intelligence” (Siti 1-2).

Description

Submitted to the Undergraduate Library Research Award scholarship competition: (2024). 11 pages.

Keywords

wood veneer, self-tying knot, wood knots

Citation