Kingston University’s Imogen Hedges remembers her grandmothers hand-knitted sweaters and how they'd get thrown out once they no longer fit her. She's designed an alternative to throwing those sweaters out using a most unusual contraption she built from a bicycle. It's called the "Un-Knitting Machine," and it is one of the most clever uses of pedal power we have ever seen. Check out the video below for a full explanation and demonstratino of how it works:

Related: The "Cyclo-Phone" is a Bicycle-Powered Music Machine

[via Kingston University]