Hi, my name is Nigel Barnett. I am an undergraduate student at MIT in the class of 2025 studying aerospace engineering. I am currently on the MIT Rocket Team and work as an undergraduate researcher for the MIT Space Propulsion Lab. I enjoy designing, building, and taking things apart to understand the real-life aspects of engineering.View Resume Contact Me
I wanted to build a fun and functional device, and thanks to ProjX funding, I had a $500 budget. This budget was perfect for building this pair (or two pairs?) of night vision goggles which I had been interested in making. Besides the cool factor, I thought they might help me traverse a dark room after my roommates go to sleep.
The light from the display passes through a biconvex lens. The lens corrects the picture, so the screen is clear, which is vital because the screen is too close to your eye for it to focus easily. This adjustment helps prevent eye strain caused by your eyes constantly trying to focus on the screens.
I built during IAP 2023 through the D-Lab class EC.S02. It's a single-speed road bike with an emphasis on modularity. While the bike was only supposed to take a few days of work to complete, I added lots of details and tweaks to the class design that made the project more fun but also more complex to complete. The steps I took in roughly chronological order are the following:
Thirteen steps doesn't sound so bad for such a good end product, but in reality, there are actually three to ten sub-steps to each step.
Overall, I'm pleased with how Tangerine turned out. There are a few bad welds and already some nicks in the paint, but I did an excellent job for my first bike. The riding feeling is also fairly smooth, but my perception may be somewhat skewed since I haven't ridden a bike seriously in a while. As for the basket, I've made a design but have yet to finish it since I already have a back rack that is sufficient to hold my backpack or my groceries.
I'm excited to ride Tangerine more and all the places we'll go to in the future.
1.44 mi (2.32 km)
I had a better start compared to the tricycle. Based on how difficult it was to make the tricycle work, I started by refurbishing and revitalizing an older vehicle of MITERS instead of designing one from scratch. The scooter was owned by previous MITERS member and president Mason Massie. By some means, the old battery combusted while inside the scooter body. Thankfully, the battery compartment of the scooter's steel frame was the only part horrifically charred and gross. So after cleaning out the internals and removing some external rust with a wire brush and flap sander, I had a scooter frame with handlebars, wheels, and motor already mounted.
to make the scooter run again was to build a new battery. Taking what I learned from the first pack I made for the tricycle, I made a frame out of a laser-cut acrylic sheet to support the battery cells better. While this wasn't as good as an off-the-shelf solution and still required some structural hot glue for rigidity, this pack felt more solid than the first. I used the N51 spot welder instead of a handheld unit to attach the same lithium-iron phosphate batteries in a ten series and four parallel (12S4P) configuration. After I attached the battery management system (BMS) to the pack, I was done (or so I thought). After finishing the battery pack, I painted the frame for rust protection and, most importantly, aesthetics in my favorite color: orange.
set by my tricycle project, problems started at the halfway-ish point of my scooter refurbishment. It turned out that sitting on a rack for the entirety of quarantine (and probably longer) wasn't great for the cheap scooter tires on the frame, so I had to replace the rear tire. After that, which you can see in photo six, the battery was somehow TOO BIG. I figured out that the added spacing from the battery frame and wiring made the pack too large. For the record, I had fit-checked the four cells beforehand. I was somewhat at my wit's end between the difficulties I had making the battery pack and all the other school things going on, so I took a hiatus from the project.
(or hacksaw job, haha) solution to the problem was to cut off a row of series cells, making the pack 10S and 3P. While lopping off ten cells reduced the capacity, the pack now fit into the battery compartment, and I could ride the scooter for the first time. While I could travel to the edges of campus comfortably, I constantly had to charge the battery with a modified off-the-shelf wall charger to ensure I wouldn't have to walk back. Because of this, I decided to make a new battery pack.
Joseph, another MITERS member, generously gifted me three UPS battery modules he had crufted. These modules contained four bundles of four 18650 battery cells, meaning I had 48 18650 batteries to work with. Well, it was actually only 40 because I screwed up two cell packs when I salvaged the batteries. So I now had a 40-cell, 10S 4P battery pack which was smaller and theoretically higher capacity than my previous battery pack. I spot-welded the battery before leaving for summer 2022 but did not attach a BMS.
I came back in the fall of 2022 to complete the battery pack and make the scooter functional again. I tested the battery to make sure it was okay after sitting around all summer, and to my dismay, one of the rows of cells was almost 2 volts lower than the rest. This meant that there was some problem with the battery pack. After slowly charging the row to balance the battery pack manually, I tried charging the battery from a bench power supply. Immediately after I turned on the power supply, the nickel strips connecting the cells turned red hot, meaning something was seriously wrong with my pack.
pending the disassembly of the battery, which would be difficult to do without damaging the battery or buying new cells.