Thanks to a new manufacturing procedure, MIT researchers have designed smart textilesthat adapt to the body in order to be able to detect the movements and posture of the wearer.
The researchers used the method of thermoforming. By adding a unique type of plastic yarn and incorporating heat to melt it slightly, researchers dramatically increase the accuracy of pressure sensors woven into multi-layer knitted textiles, calling it 3DKnits.
They used this procedure to design a “smart” shoe and mat while creating a software and hardware system to interpret and measure pressure sensor data in real time.
More so, the machine learning system predicted the yoga movements and poses of people standing on the smart textile mat with 99% accuracy.
Irmandy Wicaksono, a research assistant at the MIT Media Lab, believes that the manufacturing procedure takes advantage of the digital knitting system and allows rapid prototyping, simply scaling up for large-scale production.
This method or technique can have several applications, particularly in rehabilitation and health care. For example, it can be used to make smart shoes that follow the gait of someone learning to walk after an accident, or socks that follow pressure on the feet of diabetic patients to prevent ulcers from forming.
According in Wicaksono“With digital knitting, you have this freedom to design your patterns and also embed sensors into the structure itself, so it becomes seamless and comfortable, and you can develop it based on the shape of your body.”
For materials, MIT lead author Joseph A. Paradiso said“Some of the first pioneering work on smart fabrics took place at the Media Lab in the late 90s. Materials, embedded electronics and manufacturing machinery have evolved tremendously since then..”
“Now is a great time to see our research flow back into this area, for example through projects like Irmandy’s – they point to an exciting future where sensing and function flow more fluidly into materials and open up enormous possibilities,added Paradiso.
About the knitting know-how
To create a smart textile, MIT researchers are using a digital knitting machine that weaves layers of fabric with rows of functional and standard yarns.
The multi-layered knitted textile has two layers of conductive yarn knit sandwiched on a piezoresistive knit that changes resistance if compressed.
With a pattern, the machine sews the functional thread onto the textile in vertical and horizontal rows. The areas where the functional fibers intersect will form a pressure sensor.
Meanwhile, the yarn is supple and soft, the layers often shift and rub against themselves if the wearer moves. This creates noise and encourages variability, which makes pressure sensors less accurate.
To solve the noise problem, Wicaksono incorporated fiber thermoforming and fusion in smart textile manufacturing procedure.
In a nutshell, the researchers aim to develop a comfortable, form-fitting fabric that knows the activities of its wearer, such as running, walking and jumping.