Fitting clothes isn’t always determined by tailoring choices. For example, the global pandemic has highlighted the need for masks that effectively seal around the nose and mouth. But faces and their features vary from person to person, so one-size-fits-all masks may be less effective. Well-fitting masks are proving to be a sought-after accessory.
Lavender Tessmer, a doctoral student in MIT’s Department of Architecture, has developed a new reactive fiber and designed a process that uses heat to activate masks and make them stick to their skin, combined with specific knitted textile structures. Fits the human face. With standard textile equipment and new customization processes, any manufacturer can create custom masks.
Before coming to MIT in 2017, Tessmer had no formal experience with textiles. She began collaborating with Skylar Tibbits, associate professor in the Department of Architecture and founder of the Self-Assembly Lab, whose research topics include programmable materials—simple materials that can be activated to sense, respond, and transform. The next year, the lab purchased an industrial flat knitting machine, a type of machine common in textile manufacturing around the world, and Tesmer began learning how to operate it.
“It has a huge learning curve, and there are countless things you can do with a machine like this,” Tesmer said.
Her early introduction to knitting machines was a foresight for her subsequent work.
one step ahead
A few years before the pandemic, Tibbits’ lab received funding from Advanced Functional Fibers of America (AFFOA) to develop “smart textiles” that could sense, respond and transform. The research led to a collaboration with Ministry of Supply, a fashion company specializing in high-tech clothing, to develop a new “smart textile” system. Founded by MIT graduates, Ministry of Supply uses temperature-regulating materials to design and produce environmentally sustainable apparel for professionals.
In the spring of 2020, a series of events occurred that transformed their collaboration. Global pandemic forced businesses to close in March; Architecture department calls for proposals to fund research positions so students can work with faculty to conduct “crisis-related research,” including designing responses to the pandemic; Masks to protect first responders and the public The need became apparent. Tibbits’ research has been supported by departmental funding.
“Lavender was already experimenting with making custom-fit textile garments, so we could quickly transition to making custom masks,” Tibbits said. “But the main challenge with any customization is you can’t make every mask unique. It becomes a factory logistics issue. You have to be able to mass-produce these. Customers don’t want to wait weeks or months to get their unique mask.”
So, how are mass-produced masks tailored to individual face shapes?
“Lavender creates the knitted structure of the mask—the architectural structure,” Tibbits says. “The material properties themselves don’t lead to precisely transformed behavior. It’s basically a two- or three-dimensional knitted structure, and each stitch changes the structure and material.”
Tessmer has also developed one of two active fibers required to respond to heat (the other is already commercially available) so that the fabric can be controlled in a predictable way.
“There has to be a clear relationship between the amount of heat applied, the method by which the robot applies the heat, and the predictable results of the fabric’s dimensional transformation,” Tesmer said. “It’s an iterative process of developing multiple layers of fabric, measuring its dimensional changes, and then ultimately being able to have a robot apply heat in a repeatable and predictable way.”
Existing guidelines for the measurement ranges of human facial features are already in the public domain. Before being transformed and customized, the mask’s initial shape is large enough to fit nearly every face. From there, Tesmer inputs the dimensions of a person’s face and then activates the knitted masks with a robotic arm equipped with a heat gun, which applies heat in specific patterns to precisely tailor them to facial dimensions.
Mask demand driven by COVID-19
As retail operations closed early in the pandemic, the supply department pivoted from making clothes to making masks.
“The advantage of Lavender and Skylar’s work is that it leverages additive manufacturing technology to start production very quickly,” said Gihan Amarasiriwardena ’11, co-founder of Ministry of Supply and company president. “Because of our ability to use 3D computer weaving technology, working with self-assembly labs, we were able to design, test and develop a mask in five days and produce 4,000 masks for health care workers in two weeks. I think this will be A key asset to enable rapid conversion of existing materials to masks in the future.”
“The goal is to modify masks so that they fit perfectly on anyone’s face, which is a significant challenge for masks and other garments,” Tibbits said. “Nobody really knows how to do that other than hiring a tailor or having a lot of standard sizes that don’t fit perfectly.”
It’s worth noting that Tesmer and Tibbits’ work focused on the fit of the mask, rather than the properties needed for the mask material to filter airborne particles – although standard filters can be used to enhance their effectiveness. Masks are also reusable and washable.
“The goal is to use better fibers and a controlled, repeatable process to create custom masks,” Tesmer said. “We made masks for nine different people to demonstrate the effectiveness of this process.”
Last fall, a paper they co-authored, “Personalized Knitted Masks: Programmable Shape Changes for Custom Fits,” provided instructions for creating “truly customizable masks” that conform to any individual’s unique facial features. The Architectural Computer-Aided Design Association (ACADIA) awarded Tessmer and Tibbits the Best Paper Award for this groundbreaking work.
In their speech, the judges noted: “The award emphasizes the exemplary nature of this paper, demonstrating innovative research that makes a significant contribution to the field described.” “In addition to demonstrating rigorous research methods and subject expertise, this paper The paper is also well written and brings new insights to the ACADIA community and beyond.
The evolution of SARS-CoV-2 variants demonstrates that the need for high-quality masks will continue, and the Centers for Disease Control will continue to support their use. Amarasiriwardena believes consumer interest and demand for masks will continue, even if it’s just seasonal, as people stay indoors more frequently. He said the second question customers ask, after the efficacy of the filter media, is the fit and comfort of the mask.
“Overall efficacy is closely related to fit, which can be achieved through personalized manufacturing,” says Amarasiriwardena. “The Self-Assembly Lab has been pushing the boundaries of additive manufacturing, and their recent work in textiles combines with their expertise in ‘hacking’ CAD-CAM processes to create truly novel soft goods. While most attention Most efforts have been focused on 3D printing durable goods, but their innovations in textiles demonstrate the widespread use of self-assembly technology.”
The masks are a good case study, Tesmer said, because they have been a sought-after accessory over the past few years and there are glaring issues with how the masks are worn. She hopes to apply the process to other types of clothing and accessories, such as sweaters and shoes.
“At the end of every project, you always find areas for improvement,” Tesmer said. “There are a lot of developments for future fabrics, for example. But I’m happy with this project because it’s a valid proof-of-concept for my idea, and I believe it’s feasible.”