When people think about aerospace engineering students, they probably picture someone buried in problem sets, solving differential equations at 2 a.m. And yeah, that’s part of it. But if you ask me what’s actually shaped the way I think as an engineer, it’s not the homework. It’s the random stuff I built just because I was curious.
Two of my favorite projects had absolutely nothing to do with my coursework.
The Fingerprint Doorknob
My fraternity brothers had a habit of breaking into my room and messing with my stuff. Flipping my bed over. Moving things two inches to the left. The kind of thing that’s annoying and hilarious in equal measure. The fraternity had a master key, so at first it was pretty easy for them to get in.
I bought a new doorknob that didn’t work with the master key. They responded by buying a lock picking kit and using that. But lockpicking was cumbersome and time-consuming, so they tracked down the exact same doorknob model I’d bought, figured it probably used the same key, and it did. So they had a key to my room again.
At that point I thought: what if there’s no key at all? What if I made it so that only I could open it? Biometrics was the solution I came up with so a fingerprint scanner should do the trick.
I took apart the existing doorknob to understand how it worked. The whole mechanism is surprisingly simple: a square metal shaft rotates when you twist the knob, which pulls a latch in and out of the door frame. Once I understood that, I cut off the shaft, bought a servo motor online, and 3D printed a custom adapter to connect the servo to the mechanism. Now instead of your hand rotating the knob, the servo did it, triggered by a fingerprint scanner. My fingerprint. Nobody else’s.
I also CAD’d and printed a clean housing that concealed all the electronics and just showed the scanner on the front. Sleek, functional, and the final move in an arms race my friends started but didn’t win. Exactly my kind of project.
Was it the Fort Knox of college room security? No. But it worked! And more importantly, I got to practice my tinkering skills in a way that I didn’t get to do in the classroom. I looked at the lock system, took it apart, figured out how it worked, and rebuilt it to do something new.
The Treadmill Wing
This one started with a question I asked my professor after an aerodynamics lecture on the Magnus Effect (the phenomenon where a spinning object generates lift because of the pressure difference it creates around itself).
I talked to him after class and asked: What if the skin of a wing moved like a treadmill? Would it generate more lift?
My professor’s answer was essentially: Sure… Ok, that’s weird. You should try it.
So I did. I started designing and building a wing where the surface itself could move, essentially like a rotating skin. This would amplify the pressure differential and generate additional lift beyond what a conventional airfoil produces. I built out a solid prototype. The next step is wind tunnel testing, although I haven’t quite gotten to that yet.
Now, would this ever go on a commercial plane? Probably not. As it turns out, modern aircraft don’t actually need more lift, they need less drag. More lift generally means more weight, more complexity, more cost, and zero improvement in fuel efficiency. The lift-to-drag ratio matters more than raw lift.
But as I think about it, I believe there are situations where you’d want maximum lift regardless of drag, such as places with very short runways (like aircraft carrier ships) and aircraft used for other very specialized uses. My idea is a good one, just waiting for the right application.
Why This Matters
The classroom gives you the vocabulary, but the tinkering is what gives you the fluency.
You can learn Bernoulli’s principle in a lecture hall. But you don’t really own it until you’ve stayed up late trying to figure out whether a moving wing skin could change everything. And then worked through exactly why it probably won’t, and exactly when it might.
The engineers I want to work alongside (and the kind of engineer I’m trying to become) aren’t just people who can solve the problem in front of them. They’re people who can’t stop asking “what if” about the problems nobody assigned them. That’s what the doorknob and the wing were about. And it’s probably whatever I build next will be about. Who knows what I might try next?