Ministry of Supply will tailor this sweater to your body while you wait

The collaboration with MIT’s Self-Assembly Lab points to the future of customizable fashion.


You’re shopping for a sweater, and you spot an adorable one. But there’s a problem: You’re right between a small and a medium, and neither size is quite right.


In 2019, you’ll be able to buy a sweater from the direct-to-consumer fashion company Ministry of Supply that will adjust to your size on the spot, using only heat. That means you could grab a medium off the shelf, and after Ministry of Supply takes your measurements, an in-store robotic machine will use a heat gun to adjust the sweater to your size right before your eyes.

The technology, developed by the Self-Assembly Lab at MIT, provides a clever solution to the problems of mass customization. For years, fashion companies have explored how to mass-produce custom garments, but problems with efficiency and affordability have held up mass adoption. The collaboration between Ministry of Supply and the Self-Assembly Lab approaches the problem from a different perspective: Their sweater, coming to stores within a few months for a still-undisclosed price, can be mass-produced in standard sizes. The customization process happens in-store, instead of during the production process.

This smart sweater doesn’t need a battery, nor is it robotically knitted using metal thread or shape memory alloy, which would traditionally be used to make a material change its form. Instead, the fabric shrinks when exposed to heat, thanks to both the structure of the knit and the combination of materials used. While the researchers wouldn’t get more specific about those materials, they say that the shape-shifting technology depends on the way that two different off-the-shelf materials interact together when they’re exposed to heat.

“People want to make smart garments and shoes, but they’re always putting batteries in your shoes,” says Skylar Tibbits, the founder and co-director of the Self-Assembly Lab. “We want them to be active and smart, but passive in the sense that it’s all based on materials.”


Tibbits and his team developed the fabric through hundreds of experiments, combining different types of materials together and then trying out different knitting patterns to see how they would react to each other when exposed to heat. The research, which is part of a grant from the MIT-based nonprofit organization Advanced Functional Fabrics of America, was originally aimed at creating reversible transformations when it comes to shape and porosity, to make garments more breathable or waterproof based on temperature and moisture. But the team unexpectedly stumbled upon a way to create a permanent transformation, which is what enables this kind of custom tailoring.

Tibbits says that original research into reversible transformation–for instance, a jacket that could become waterproof when it comes into contact with moisture, and then become more breathable again when it’s dry–will continue. For now, his team is working with Ministry of Supply to turn their discovery about permanently changing a garment’s shape using heat into a full-fledged commercial product, starting with the company’s forthcoming in-store sweater customization experience.

[Photo: courtesy Self-Assembly Lab/Ministry of Supply]
Boston-based Ministry of Supply, which was founded on the idea of bringing performance fabrics usually used in sports to professional attire, has experimented with robotic knitting and customization before. A few years ago, the company released a robotically knit blazer that customers could personalize by changing details like the cuff color and the yarn type. More recently, the startup offered a customization experience in its Santa Monica store, where it took a thermal map of a customer’s body and then added ventilation to specific areas that tend to overheat (like the underarms). Each experiment has allowed the company to test out new technology for customizing a different aspect of design–from aesthetics, to functionality, to fit–and Gihan Amarasiriwardena, cofounder and president of Ministry of Supply, eventually hopes to scale these experiments up so the custom garments are available to more people.

“The vision is one-hour photo,” Amarasiriwardena says. “That’s something we’d love to bring to clothing.”

Within the next three or four months, Amarasiriwardena hopes to station a six-axis robot inside one of Ministry of Supply’s stores, where customers can watch it use heat to alter the sweaters. Tibbits thinks there will be something psychologically rewarding about the experience of watching a garment transform before your eyes. Other “smart” textiles might claim to change based on your body’s temperature, but they don’t visually show the change taking place. Watching a robot with a heat gun moving around your sweater, transforming it in moments, is a very different experience.


“You want to see that it’s actually active, that it’s alive and transforming with you and around you,” Tibbits says. “Most products in our world don’t adapt unless they’re robotic. This is more lifelike, where it has a natural transformation you expect in natural things.”

The MIT team will continue to work on more applications of these active textiles over the next year, as part of the Self-Assembly Lab’s larger goal of creating “programmable” materials. The collaboration is a major step forward for the lab, which has worked on commercial products before–but has never launched a textile that you’ll actually be able to buy.

The MIT Self-Assembly Lab team included Lavender Tessmer, Carmel Snow, Sophie Richter, Schendy Kernizan, Jared Laucks, and Skylar Tibbits. Ministry of Supply’s team inlcuded Gihan Amarasiriwardena and Aman Advani. Other collaborators include John Hart of the Mechanosynthesis Group at MIT; Rui Li and Guowen Song of Iowa State, and Tim Robson and Jeff Haggard of Hills Inc. 

About the author

Katharine Schwab is the deputy editor of Fast Company's technology section. Email her at and follow her on Twitter @kschwabable