Level 1 — Absolute Beginner
Some engineers at Harvard made a new kind of cloth. The cloth can change its shape. It can snap into different shapes, like a switch.
The cloth is made by a knitting machine. Knitting machines usually make sweaters and socks. The engineers use the same kind of machine. They do not need new tools.
The cloth uses special stretchy yarn. The pattern of the knitting is also special. Together, the yarn and the pattern make the cloth snap between shapes.
The engineers also put a special wire yarn in the cloth. This wire can turn on a light. It can also count steps. The cloth becomes a switch that you can wear.
- fabric
- Cloth made by weaving or knitting threads together.
- engineer
- A person who designs and builds machines or structures.
- knit
- To make cloth by looping yarn together with needles or a machine.
- yarn
- Long thread used for knitting or weaving.
- elastic
- Able to stretch and then go back to its first shape.
- switch
- A device that turns something on or off.
- shape
- The outer form of an object.
- wearable
- Something you can wear, like clothes.
Level 2 — Elementary
Researchers at Harvard's John A. Paulson School of Engineering and Applied Sciences, led by Kausalya Mahadevan in the lab of Professor Katia Bertoldi, have created knitted fabrics that can flip between several different stable three dimensional shapes. The fabric does this without any rigid parts or complicated mechanical pieces inside it.
This kind of material is called a mechanical metamaterial. That means its strange behavior comes from how it is built, not from what it is made of. The shape changing effect, called multistability, comes only from the type of elastic yarn, the knitting pattern, and normal settings on standard industrial knitting machines.
Because the fabric uses standard machines, factories that already make regular clothing could produce it without buying new equipment. The team also knitted a thin conductive yarn into the fabric alongside the elastic yarn, turning the shape changing fabric into a soft electronic switch.
When the fabric snaps from one shape to another, it can turn a light on or off, count how many steps a person takes, or sense other movement. To show this off, the researchers built a lampshade that changes color depending on which shape its knitted switches have snapped into. The work was published in the journal Advanced Functional Materials.
- metamaterial
- A material whose unusual behavior comes from its structure rather than its ingredients.
- multistability
- The property of having more than one stable shape or position.
- conductive
- Able to carry electricity through itself.
- industrial
- Relating to factories and large scale manufacturing.
- prototype
- An early working model built to test an idea.
- mechanism
- A system of parts that work together to perform a task.
- elastic
- Able to stretch and return to its original shape.
- reconfigurable
- Able to be rearranged or changed into a different form.
Level 3 — Intermediate
At Harvard's John A. Paulson School of Engineering and Applied Sciences, a research team led by Kausalya Mahadevan, working in the lab of Professor Katia Bertoldi, has developed knitted fabrics capable of snapping between multiple stable three dimensional configurations, achieving this multistability without any rigid components or intricate mechanical assemblies embedded in the cloth.
The fabrics belong to a class of materials known as mechanical metamaterials, whose unusual physical behavior arises from their internal structure rather than from any special ingredient in what they are made of. In this case, the researchers achieved shape snapping purely through the choice of elastic yarns, the geometry of the knitting pattern, and standard settings already available on ordinary industrial knitting machines.
That last detail carries practical weight: because no specialized manufacturing equipment is required, textile factories that already knit conventional clothing could, in principle, produce these shape changing fabrics using the machines they already own, rather than waiting on new tooling. The team extended the idea further by knitting a conductive yarn alongside the elastic yarn, converting the multistable structure into a soft electronic switch.
As the fabric snaps from one stable shape to another, it can complete or break an electrical circuit, allowing it to turn a light on or off, register a wearer's footsteps, or otherwise sense motion. The researchers demonstrated the concept with a reconfigurable lampshade whose knitted switches correspond to different colors of light, and they argue the approach points toward future smart textiles that could track movement, deliver tactile feedback, or physically change shape on demand, all without embedding hard electronics, motors, or batteries directly into the cloth.
- configuration
- The particular arrangement or shape of the parts of something.
- geometry
- The specific arrangement of shapes and structure within an object.
- embed
- To fix something firmly and deeply within a surrounding material.
- tactile
- Relating to the sense of touch.
- circuit
- A closed path that allows an electric current to flow.
- register
- To detect and record that something has happened.
- tooling
- The specialized equipment or machinery needed to manufacture something.
- viable
- Capable of working successfully in practice.
Level 4 — Advanced
A team at Harvard's John A. Paulson School of Engineering and Applied Sciences, led by Kausalya Mahadevan in the laboratory of Professor Katia Bertoldi, has demonstrated that ordinary knitting, the same craft behind sweaters and socks, can be coaxed into producing fabrics that snap crisply between multiple stable three dimensional shapes, with no rigid hardware or intricate mechanical assembly hidden inside the cloth.
The work situates itself within the growing field of mechanical metamaterials, structures engineered so that their unusual physical behavior emerges from geometry and architecture rather than from any exotic constituent material. What distinguishes this fabric is how modestly that architecture is achieved: multistability, the capacity to hold more than one stable shape, arises entirely from the selection of elastic yarns, the specific knit pattern, and settings already native to standard industrial knitting machines, requiring no bespoke fabrication process.
That reliance on off the shelf equipment is not incidental. It implies that textile manufacturers already equipped to knit conventional garments could, in principle, produce these shape snapping fabrics without new capital investment in machinery, a claim of manufacturing readiness that many laboratory scale metamaterials cannot make. The researchers pressed the concept further by knitting a conductive yarn alongside the elastic one, converting a purely mechanical curiosity into a functioning soft electronic component: as the structure snaps between stable configurations, it can complete or interrupt a circuit.
To illustrate the principle, the team built a reconfigurable lampshade whose knitted, multistable switches correspond to distinct colors of light, a modest but legible proof of concept published in the journal Advanced Functional Materials. The broader implication the researchers draw is toward a generation of smart textiles that could monitor a wearer's motion, deliver localized tactile feedback, or physically reconfigure themselves on command, all while dispensing with the rigid electronics, motors, and batteries that conventional wearable devices still require.
- bespoke
- Made or done to order for a particular purpose, not mass produced generically.
- constituent
- Being a part of a whole, an ingredient or component.
- architecture
- The underlying structural design of a system or material.
- legible
- Clear and easy to understand or interpret.
- dispense
- To do without something, or to distribute something.
- proof of concept
- A small demonstration that shows an idea can work in practice.
- capital investment
- Money spent to acquire or upgrade equipment or facilities.
- readiness
- The state of being fully prepared for use or action.