AYESHA RASCOE, HOST:
October's here, which means it won't be long before parents and caretakers in many parts of the country face an expensive question - how big are my kid's feet now? Meaning, is it time for new snow boots?
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RASCOE: Chances are the kiddos have outgrown last year's pair, which they might not have worn much anyway. It's a problem a team of Northwestern University engineering students tackled for their senior project - winter boots that could last for more than just one season. For one of them, Joanne Park, it was personal.
JOANNE PARK: I grew up in a low-income family, and so I grew up getting hand-me-down boots and always wearing my brother's shoes. So I was really interested in, how might I get my own pair of boots?
RASCOE: They did a lot of research, conducted surveys. Ben Miller looked up patents.
BEN MILLER: That's where we were able to really find, you know, something like this with a winter boot hasn't been done in a patent before.
RASCOE: Designing the boot - that part was daunting.
CALLISTA SUKOHARDJO: We had, like, a huge brainstorming session with, like, Post-it notes and everything.
RASCOE: Callista Sukohardjo was also on the team.
SUKOHARDJO: That growing component was the thing that we didn't know how to design. We didn't know how we were going to make a shoe that's typically a fixed size kind of grow on its own.
RASCOE: So they looked at things like crutches, telescopes, accordions and, Joanne Park says, some kinds of footwear.
PARK: We looked into expandable ice skates, expandable Rollerblades and expandable ski shoes. And we took a lot of inspiration from those, as well. But they have, like, harder linings in a sense. So we wanted to make our boots more flexible.
RASCOE: They settled on what they call the Sno-Gro Boot.
MILLER: If you imagine a boot and you take the middle section out and you put sort of an accordion in there, you know, that allows it to stretch in and out - and that allows it to go to different sizes, and it locks in the heel by pressing down in different locations for different sizes.
RASCOE: When the Sno-Gro is set for the smallest size, the sole sticks out a bit behind the upper boot. Then you move the heel back as the child grows, stretching that accordion.
PARK: It expands three sizes. So I'm a size 5. Callista's a size 7. And we could both wear, like, the same exact pair of shoes, which is crazy.
RASCOE: In fact, once they made up the prototype in Northwestern's lab, Joanne and Calista did just that.
SUKOHARDJO: Joanne put it on her foot, and it worked. And we were like, OK, let's expand it. And then she just handed it over to me. And I was like, OK, here goes nothing and then just stuck my foot in. And I was just, like, oh, it works. And it was great. It was, like - really big relief.
RASCOE: Since graduating last spring, Ben Miller says the team has met with several manufacturers to try to bring the Sno-Gro Boot to market.
MILLER: It's been a learning curve, but we're definitely getting better at, you know, putting our foot in the door and getting connections.
RASCOE: So it sounds like Sno-Gros won't be on the market in time for this winter - but maybe next.
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