How knitting could transform technology

Knitting, the age-old craft of looping and stitching natural fibers into fabrics, is gaining renewed attention for its potential in advanced manufacturing.

Beyond creating garments, knitted textiles hold promise for designing wearable electronics and soft robotics – structures that need to move and bend flexibly.

The mechanics of knitting

Knitting transforms one-dimensional yarn into two-dimensional fabrics that are flexible, durable, and highly customizable.

However, to develop smart textile design techniques for engineering applications, a deep understanding of the mechanics behind knitted materials is crucial.

A team of physicists from the Georgia Institute of Technology has taken the technical know-how of knitting and added a mathematical foundation to it.

Led by Elisabetta Matsumoto, associate professor in the School of Physics, and Krishma Singal, a graduate researcher in Matsumoto’s lab, the team used experiments and simulations to quantify and predict how knitted fabric responses can be programmed.

The goal of the research is to incorporate knitting into more engineering applications by establishing a mathematical theory of knitted materials.

Decoding knitted fabrics

“For centuries, hand knitters have used different types of stitches and stitch combinations to specify the geometry and ‘stretchiness’ of garments,” explained Matsumoto.

Despite its dismissal as unskilled labor, knitting involves properties that can be more complex than those of traditional engineering materials like rubbers or metals.

The team sought to decode the principles that govern the elastic behavior of knitted fabrics. These principles are shaped by the interplay of stitch patterns, geometry, and yarn topology.

“A lot of yarn isn’t very stretchy, yet once knit into a fabric, the fabric exhibits emergent elastic behavior,” noted Singal.

Experienced knitters have an intuition about which fabrics are stretchier and their best applications. Understanding these fabrics’ programmability can expand knitting’s application beyond clothing into various fields.

Experiments and simulations

The researchers conducted experiments and simulations to explore the relationships among yarn manipulation, stitch patterns, and fabric elasticity.

They started with physical yarn and fabric stretching experiments to identify key parameters, such as yarn bendability, fluffiness, and the length and radius of yarn in a stitch.

Using these results, they designed simulations to examine the yarn inside a stitch, similar to an X-ray. These simulations help see parts of the yarn that interact with others, recreating physical measurements as accurately as possible.

Through these experiments and simulations, the researchers showed the significant impact of design variations on fabric response.

“We discovered that by using simple adjustments in fabric pattern design, you can change how stretchy or stiff the bulk fabric is,” said Singal. “The manipulation of yarn, formation of stitches, and patterning of stitches completely alter the final fabric’s response.”

Knitting’s future in advanced manufacturing

The insights from this research suggest that knitted textile design can become more common in manufacturing and product design. Simple stitch pattern adjustments can change a fabric’s elasticity, pointing to knitting’s potential for cutting-edge technologies like soft robotics, wearables, and haptics.

“We think of knitting as an additive manufacturing technique – like 3D printing, where you can change material properties by selecting the right stitch pattern,” said Singal.

The team plans to further explore knitted fabric science, addressing numerous unanswered questions.

“Textiles are ubiquitous in our lives,” Matsumoto said. “Designing them for specific properties currently relies on experience and intuition. We hope our research helps make textiles a versatile tool for engineers and scientists too.”

By merging traditional techniques with modern science, this research paves the way for innovative applications of knitted textiles in various engineering fields.

The history of knitting

The history of knitting stretches back thousands of years and spans various cultures around the world. It is believed to have originated in the Middle East, with some of the earliest known examples dating back to the 11th century in Egypt. 

These early pieces were typically made using a technique known as nalbinding, which involved creating fabric by looping yarn with a single needle, rather than the two-needle method commonly associated with modern knitting.

Trade routes to Europe

As knitting spread from the Middle East to Europe through trade routes, it evolved and gained popularity. By the 14th century, it had become well-established in Spain, evidenced by the discovery of beautifully intricate, knitted items from that period. 

During the Renaissance, knitting guilds emerged, and the craft became a respected and regulated profession in Europe, with guild members producing high-quality, elaborate garments and accessories.

Scotland and Scandinavia 

In the 16th century, knitting gained further prominence in Scotland, particularly with the development of Fair Isle knitting. This technique, named after a small island in the Shetlands, involved using multiple colors of yarn to create intricate patterns. 

Meanwhile, in Scandinavia, distinct regional styles also began to flourish, with each area developing its own unique patterns and techniques.

World wars

Knitting played a significant role in the everyday life of many communities, particularly during times of war. In the 20th century, both World War I and World War II saw a surge in knitting as people made garments and accessories for soldiers. 

This period also marked the growth of knitting as a leisure activity, with an increasing number of patterns and instructional materials becoming available to the general public.

The knitting machine 

The advent of industrialization in the 19th century brought about significant changes to knitting. The invention of the knitting machine allowed for the mass production of knitted goods, making them more accessible and affordable. 

Resurgence of knitting

However, hand knitting remained a popular pastime, and the 20th century saw various revivals of interest in the craft, including a resurgence in the 1970s during the countercultural movement.

The hobby was revived yet again in the early 21st century with the rise of DIY culture and the internet, which facilitated the sharing of patterns and techniques across the globe.

The study is published in the journal Nature Communications.

—–

Like what you read? Subscribe to our newsletter for engaging articles, exclusive content, and the latest updates. 

Check us out on EarthSnap, a free app brought to you by Eric Ralls and Earth.com.

—–