More than 40 years ago, an unusual idea was born: a zipper that could do much more than close a jacket.
Instead, it could transform objects—changing them from soft and flexible into firm and rigid structures.
At the time, the idea was too advanced for available technology and was set aside. Now, thanks to modern tools like 3D printing, that vision has finally become reality.
Back in 1985, William Freeman, then working at Polaroid, proposed a three-sided zipper design. Unlike ordinary zippers with two sides, his version had three strips that could be joined together into a triangular shape.
When zipped, the structure would stiffen, turning a floppy object into something solid. Although his idea was rejected at the time, he patented it and kept the design, hoping it might one day be useful.
Fast forward to today, researchers at the MIT Computer Science and Artificial Intelligence Laboratory have brought this concept back to life.
They developed a modern version called the “Y-zipper,” along with software that allows users to design and customize it.
Using 3D printing, the system can automatically create these special zippers in different shapes and sizes.
The Y-zipper works like a flexible structure when open, but once zipped, it locks into a more rigid form.
This ability to switch between soft and firm states is known as “tunable stiffness,” and it has many practical uses.
For example, the researchers showed how the Y-zipper could make setting up a tent much faster.
Instead of struggling with poles and fabric, the zipper can help the structure pop into place quickly and easily.
The technology could also be useful in healthcare. In one example, the team created a wrist cast that can be loosened during the day for comfort and tightened at night for better support.
This makes the device more adaptable to a patient’s needs without requiring multiple tools or adjustments.
Another exciting application is in robotics. By adding a small motor, the zipper can be opened and closed automatically. This could allow robots to change shape as they move, such as adjusting their legs to walk over uneven ground. The same idea could even be used in creative fields, such as art installations that move or “bloom” when activated.
To make sure the Y-zipper is strong enough for real use, the researchers tested different materials commonly used in 3D printing. They found that some materials are stronger, while others are more flexible. In durability tests, the zipper was able to open and close around 18,000 times before breaking, showing that it can handle repeated use.
While the current version is made from plastic, the team hopes to explore stronger materials like metal in the future. They are also interested in scaling up the design for larger structures. Possible future uses include space exploration, where flexible tools could help collect samples, and emergency response, where shelters could be set up quickly after disasters.
This innovation shows how an old idea can find new life with modern technology. By rethinking something as simple as a zipper, scientists are opening the door to smarter, more adaptable designs in everyday life and advanced engineering.
