Update | 2024 Nov 17

Just wanted to share a bit about what I’ve been up to lately.

Go to PID controller

I’ve been interested in electronics/control systems and a friend of mine recommended trying this out. I got a DC motor with encoder, and was able to make a program where I could specify a position to go to (whereas the inputs to the DC motor are basically go left or go right). This clip is basically like a rotary phone motion where I gave it a phone number and it moved to each number/back to zero, mimicking the motion of a rotary phone.

I think the crazier thing for me doing this project was I had to solder some parts together. I didn’t anticipate having to do that, and I’d never done it before, but people do this when they’re in middle school, so I got the supplies and melted some metal. I’m still really baffled that it worked. Like you just melt metal over these pieces, and electricity flows through them. That’s so awesome!

Here’s the code.

XOR gate

I wanted to do some basic boolean algebra with some buttons, resistors, and an LED. I was able to do NOT, OR, NOR, AND, and NAND, but when it came to XOR I was struggling. It eventually led me to understanding transistors and diodes (and blowing up an LED), and I eventually cracked XOR (with 5 transistors).

Physics calculator

I already posted about this on twitter, but I’m just really proud of this project. I also recently added the ability to add your own units (still can’t define your own conversions…yet), which is pretty cool.

Here’s the website, code.

Pendulums

Another control systems project. I saw people online doing pendulum balancing (a friend of mine did this in an undergrad class as well). I was considering trying to do the same project in real life, but first wanted to try it out in software only since I’m still really inexperienced with hardware.

I got the basic pendulum physics working, made a super naive algorithm to balance it if it was up (basically, if leaning left, go left), then started training a genetic algorithm for swinging it upwards from below (yea…I ditched the actual control systems part and just went another way lol). That had some okay results, though seemed to reach a local maximum. Some naive tweaks in the reward function (i.e. rewarding the max height reached in addition to general time spent close to goal) helped, but not enough. After that I got distracted with a different project.

Here’s the code.

Noobular

Lately, as I’ve been interested in physics/non-software engineering, I was re-trying out Brilliant. It’s pretty cool! Earlier this year, on a whim I also did a bunch of Duolingo with my family, and lately I have been giving Math Academy a try. My experience with Duolingo was sort of mixed, but I really liked Brilliant and Math Academy. They are simple, yet interactive/engaging, and make it pretty easy to learn a little each day. They feel like a natural progression of how people teach/learn on the internet.

For certain topics they probably reach diminishing returns, but it seems like a roughly simple formula (content + interaction + chopped up into small-ish lessons + sprinkle of gamification) can go a really long way.

I really liked the simplicity of Math Academy and have had an itch to do web dev lately. So Noobular is my attempt at making a Math Academy-esque site, but where anyone can upload content.

So far I’ve gotten a basic MVP down, i.e. a teacher can create courses with modules and multiple choice questions, and a student can take those courses and their progress will be tracked.

This has also been a fun experiment using htmx and server-side rendering, whereas most of the frontend work I’ve done has been with client-side javascript frameworks like react/svelte.

Here’s the code.