PacBot

This is an ongoing blogpost about the work done as part of PacBot, a robotics club at Princeton that creates a small autonomous robot capable of playing pacman in a real maze!

I am yet to write about the actual robot and its hardware design in this post (I will soon!), but please continue reading about our maze from last year!

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In 2025, we co-hosted the annual PacBot competition with RIT, and for it, we built a maze.

Look at this beauty:

For those unfamiliar, PacBot is a real-life robotics version of the classic Pac-Man arcade game: a palm-sized robot traverses an intricate maze, collecting as many pellets as it can while avoiding four simulated, ghosts. View Pacbot 2025 here.

Naturally, the competition needs a maze. Last year at Harvard, I saw how transporting the entire maze was a huge hassle. I was excited – and definitely overconfident – but I committed to building a modular version for this year. I didn’t know the first thing about woodworking or CAD for wood. But a maze was needed, so a maze would be built.

In the fall, I experimented with different ways to attach the walls to the base. I had high hopes for a magnetic system, inspired by the way cupboard latches work, but it didn’t offer the stability we needed. Eventually, I landed on a solution: 1-inch dowels glued to the walls, which slotted into holes in the base. It was simple, sturdy, and easy to assemble. Or at least, it seemed to be, when I was experimenting with just the odd piece of wood. Replicating that process for hundreds of pieces was incredibly time and labour intensive.

Over winter break, I CADed the entire maze in Onshape. I made many mistakes – like prioritizing the 7-inch corridor width but not double-checking the overall dimensions. That led to some odd measurements (hello, 2.186 inches) that we had to round on the fly.

Most of the group also got our woodshop training done over winter break, so we were able to start working on the maze collectively over spring semester. We ran three sessions for the week, each led by either me, or one of the other co-leads, with people having the option to join any one of them. Our google sheet tracking the progress of each one of the 158 pieces became our most referenced doc. The first couple of weeks were rough, but we eventually developed an efficient factory-line system. We did run into some hiccups with certifications and permissions – it was frustrating at times, but I suppose it’s all part of the process.

One major challenge we faced was warping. I consulted someone I knew from the sculpture studio, and they recommended using OSB subflooring and pressed fiberboard. We laminated those sheets together, but I think the combination of different woods and the glue caused the base to warp. We eventually fixed it by using small sheets of acrylic and scrap wood to press down the warped areas and apply weight.

Honestly, building the maze was incredibly stressful. There were weeks when it felt like all I thought about was wood. The pressure of the deadline, the mental and physical exhaustion of cutting and assembling everything, multiple Home Depot trips hauling massive sheets of wood, and then dragging them up multiple flights of stairs – it was a lot. It is part of the reason I want to get really jacked. For the wood, if not for anything else, haha.

But it was all worth it. In my very unbiased opinion, the maze came together beautifully. Our bot didn’t get stuck, everything ran smoothly, and seeing it in action made all the effort feel meaningful. There are sections of the maze propped up by sheets of newspaper, but it still turned out decent, and I’m really proud I went through the process of making it.

More than anything though, I’m just so grateful for the entire team and my co-leads who were there with me through every single part of this – and my friends who tolerated me cribbing about this literally every day for two months. People took time out of their lives (some of them were out here writing their entire final theses!!) and even cut night-outs short just to drive to Home Depot. I honestly could not have done this without them. It was such a team effort, and I feel really, really lucky to have gone through this with such solid, thoughtful people.