Andres writes in..
My name is Andres Guzman-Ballen and I’m a senior majoring in computer engineering at the University of Illinois @ Urbana-Champaign.
Thanks to the detrimental changes of the bus routes at UIUC, I had to resort to either skateboarding everywhere, walking, or riding a bike to get around campus. All would require more effort than I wanted to put in to get around and that’s when I came up with the idea.
This isn’t an original idea since there are already electric skateboards out there in the market and some people have made their own electric mountainboards as well but in my opinion, they weren’t efficient in any manner. Most use lead batteries, brush motors, a bulky skateboard design, and are wired (which to me isn’t as cool). This makes it incredibly heavy (45-60 lb) since a 10 volt lead battery can weigh 10-15 pounds alone and a brush motor to power a skateboard usually needs at least around 24 volts to be decent. A good brush motor can weigh 10 lbs as well. There’s a spiral where the heavier the board, the stronger the equipment has to be and this in itself makes it heavier. Many also limit their designs to the skateboard.
I chose a mountainboard because the truck design allows the rider to carve more since the center of gravity is lower than a skateboard. Because it is designed to bend and absorb impacts and still be very strong (with the carbon fiber and fiberglass combo), riding it feels as if you are surfing in the street. I use a 25.6 V 10.2 Ah LiFePO4 battery and it weighs only 6 lbs! The brushless motor that I use only weighs 0.6 lbs and the board that I bought from eBay weighs about 18 lbs. If you add that up with the material supporting all that, it weighs about 30 lbs. It can go up to 20 mph but I usually ride around 10 to 15 since I want to live long enough to enjoy it.