---
title: "MIT CSAIL brings 40-year-old zipper concept to life with 3D printing"
url: https://www.voxelmatters.com/mit-csail-brings-40-year-old-zipper-concept-to-life-with-3d-printing/
date: 2026-05-09
modified: 2026-05-09
lang: en
author: "Joseph Caron-Dawe"
description: "A zipper concept patented in the 1980s and then shelved for nearly four decades has been revived by researchers at MIT's Computer Science and Artificial Intelligence Laboratory (CSAIL), who used..."
categories:
  - "3D Printing Processes"
  - "Research & Education"
  - "Thermoplastic Polymers"
tags:
  - "future"
image: https://www.voxelmatters.com/wp-content/uploads/2026/05/MIT-Y-zipper-01-640x400.jpg
word_count: 349
---

# MIT CSAIL brings 40-year-old zipper concept to life with 3D printing

A zipper concept patented in the 1980s and then shelved for nearly four decades has been revived by researchers at [MIT's Computer Science and Artificial Intelligence Laboratory (CSAIL)](https://www.voxelmatters.com/mit-csail-creates-generative-ai-tool-to-3d-print-personal-items/), who used 3D printing to produce a working version of the device.

William Freeman, then an electrical engineer at Polaroid and now an MIT professor, originally conceived the three-sided zipper in 1985 after submitting it to a design competition. His proposal was a triangular fastener capable of switching objects between soft and rigid configurations, but it was rejected, and the prototype sat in storage until CSAIL researchers took an interest in its application for structures with tunable stiffness.

![MIT CSAIL brings 40-year-old zipper concept to life with 3D printing](https://www.voxelmatters.com/wp-content/uploads/2026/05/MIT-Y-zipper-02-340x213.jpg)CSAIL researcher Jiaji Li and Professor William Freeman

The team built an automated design tool and a 3D printed fastener, which they have named the "Y-zipper." The software allows users to specify strip length, bend angle, and one of four motion configurations (straight, bent, coiled, or twisted) before the system fabricates the zipper autonomously [using plastic filament](https://www.voxelmatters.com/axjos-introduces-filament-spools-made-from-100-recycled-plastic/). The fasteners can be attached to or embedded within camping equipment, medical gear, robotic systems, and art installations.

“A regular zipper is great for closing up flat objects, like a jacket, but Freeman ideated something more dynamic. Using current fabrication technology, his mechanism can transform more complex items,”said MIT postdoc and CSAIL researcher Jiaji Li, lead author on the paper. “We've developed a process that builds objects you can rapidly shift from flexible to rigid, and you can be confident they'll work in the real world.”

## Material testing and fabrication limits

[The team ran stress tests on polylactic acid (PLA) and thermoplastic polyurethane (TPU)](https://www.voxelmatters.com/all-about-tpu-and-other-thermoplastic-elastomers-for-3d-printing/), which are the two plastics most commonly used in fused filament fabrication. PLA demonstrated higher load tolerance while TPU offered greater pliability.

In a separate durability test, a Y-zipper withstood 18,000 open-and-close cycles before failure, which the team attributed to the device's elastic structure distributing stress across its geometry.

Li said that stronger materials such as metal could extend the design's durability further, and that larger-scale versions remain out of reach on the team's current 3D printing platform.