When most people have a Halloween costume idea, they either hope they can salvage something in their closet or pray they can make it to a Spirit Halloween before its shelves have been emptied.
Christina Ernst, on the other hand, gets to work in her lab.
The 27-year-old Chicagoan, known on TikTok as @shebuildsrobots, is a software engineer by day, and something of a fashion mad scientist by night–crafting what she calls “wearable tech” that combines creative flair with technological ingenuity.
“I like things that are whimsical, things that look more magical than technical,” says Ernst. This year, she was inspired to pay homage to the 2007 Disney/Pixar film Ratatouille, the tale of a culinary-minded rat that takes control of a hapless human and directs him through the kitchen by tugging on his hair and moving his limbs like a marionette. To realize her real-life Remy, Ernst decided to craft a fully functional animatronic of the lovable rodent chef, utilizing her 3D printer, a few tiny motors, some clever coding, and a few helpful tips from her fans.
“I love making fun, wearable tech projects and with Halloween coming up I thought this was a great opportunity,” she explains. “Everyone knows Ratatouille, even though it was a movie with no sequels and came out over a decade ago now…it just has cultural staying power, you know? Not to mention: A rat piloting a human? I thought it would be a fun little project.”
Ernst cataloged her project’s progression on her website and TikTok channel, where she has over 82,000 followers. While it’s often advisable to “not read the comments” when you’re a social media personality, Ernst found her community more helpful than disparaging. “In this case, this might be the most positive reception I’ve had to a video,” she says. “The comments were helpful and had some great suggestions,” such as coding the tiny robot rat to actually mirror her arm movements. While she does get her fair share of trolls–most of whom claim she’s just “the face” for some unseen (and male) genius who actually does all the work–Ernst has found a way to tune them out.
“For me, the most meaningful comments are when people say, ‘I’m a high school senior and this convinced me to study engineering in school.’ That is so rewarding. And that cancels out everything else.”
In fact, it takes Ernst back to where it all began. A self-described “math nerd” growing up who also loved to make her own clothing (“Which has a lot more math than people realize–it’s all algebra and geometry!”), she attended a Hackathon while in college and showed off the first wearable tech project she ever made: a Bluetooth-controlled, light up, color-changing dress. The response was immediate, and surprising. “I was blown by how many girls and young women were coming up to the table and saying, ‘I have absolutely no technical coding background but I want to learn specifically so I can make this dress – can you teach me?’,” says Ernst. “And that was a lightbulb moment for me.”
Utilizing now-accessible technology like 3D printers and laser cutters, which Ernst refers to as her “power tools,” she found the perfect way to combine her passion for creative expression with her desire to inspire more girls to pursue careers in science and technology. Ernst also currently serves as the Chicago Public Library’s “Maker in Residence,” a temporary position where she teaches coding classes through the institution’s Maker Lab. She is also designing a wearable tech dress inspired by the history of Chicago to be displayed in the library’s windows this holiday season. And this November, Ernst will be seen on the STEM-themed CBS series Mission Unstoppable with Miranda Cosgrove, mentoring even more engineering-curious young women.
While Ernst still has a few “dream projects” in mind–for one, she admits she’d love to do a big annual tech look based on that year’s Met Gala theme–she won’t forget to put the finishing touches on Remy before October 31. Especially when the voice of Remy himself, comedian and actor Patton Oswalt, has taken notice of her handiwork and posted his reaction on X.
“That was so unexpected! I never would have thought this silly little project would get that attention,” says Ernst. “I’m sure people make Disney projects all the time, so the fact that he noticed this and was impressed–I was so honored!”