A sudden snow squall at noon, a scorching asphalt marathon, or an air-conditioned office that never quite gets the temperature right—these are the daily extremes our clothes were never built to handle. In a sweeping review published in Nano-Micro Letters , researchers from The Hong Kong Polytechnic University, led by Professor Dahua Shou, introduce a 3D self-folding knitted fabric that thinks like a thermostat. It toggles between radiative cooling and passive warming simply by stretching or relaxing, delivering year-round comfort without extra layers, without batteries, and without compromise.
Why Shape-Shifting Matters
Traditional “dual-mode” textiles either flip two layers like a reversible jacket or rely on bulky phase-change capsules. They add weight, trap sweat, and often fail halfway through a long day. The new fabric sidesteps every limitation by leveraging geometry itself . A single sheet of yarn is programmed—stitch by stitch—to curl into a 3-D accordion when relaxed, then flatten into a 2-D sheet when tugged. No hinges, no electronics, no extra seams.
Inside the Origami Thermostat
Warming Mode – 3-D Air Fortress
Cooling Mode – 2-D Radiator Sheet
Knitting the Future, Stitch by Stitch
From Lab Bench to Backcountry
Prototype garments—shirts, sleeves, and full jackets—have already logged field hours in Hong Kong’s 32 °C midday sun and 15 °C mountain dawns. Volunteers reported no clammy feel , even after 4 hours of cycling, thanks to the Coolmax backbone and micro-gaps between coated yarns. The fabric’s 176 g m -2 areal mass is lighter than a standard running tee, and the transition from 3-D to 2-D can be triggered by a simple cuff tug—no zippers, no gadgets.
Next Moves
The team is now embedding humidity-sensitive yarns that automate folding in high humidity (sweat) and unfolding when dry, moving toward a hands-free climate jacket . Military, disaster-relief, and commuter markets are already in discussion, with pilot lines slated for late 2025. Long-term, the same origami-knit logic could wrap EV battery packs, drone skins, or refugee shelters—anywhere the weather refuses to stay put.
Nano-Micro Letters
All-Weather 3D Self-Folding Fabric for Adaptive Personal Thermoregulation