Edgerton Center Engineering Design 2010: Project Highlights

What did you do this summer??

I think the projects speak for themselves, but in case they don't I'll be happy to throw in my own passive-aggressive editorial.

A message to MIT Project Classes (yes you, 2.007/2.009/6.01/6.131/etc): This is what we do at the Edgerton Center in three weeks with high school students.When they come to MIT, they will be bored by what you have to offer. Start making cooler stuff faster or you will lose your most talented students to apathy and/or frustration.

That out of the way, here's a brief run-down of the projects. Some of them may get posted as Instructables in the near future.

Quadrotor!
In each project, an MIT student works with a group of [2 to 6] high school students to research, design, and build a real engineering project. There were supposed to be three projects, but so many people wanted to make a quadrotor that it became the fourth and largest group. And of course I got drafted into leading it.

I have literally zero experience with flying vehicles, but for whatever reason the quadrotor team took my very brief and pulled-out-of-somewhere explanation ("It's like two segways and a tank steer robot.") and ran with it, producing a functional, if twitchy, quad copter build for about $250 with parts from Hobby King and Sparkfun. You might not believe me, but I barely did any work on this project. The fact that it flies is sort-of amazing. It's definitely getting an Instructable.

LED Pong
First there was Pong. Then there was Beer Pong. Now there is LED Pong. The game is played on a 4x3x(8x8) LED matrix. (That's 768 individually-soldered LEDs.) It's just like original pong, except that, like 3/4 of this year's projects, it's controlled by two accelerometers.

Bling Segw@y
I must admit I am deathly afraid of posting video of this on the internet. The reason being that I fear the torrent of emails that will follow. I lived through the first DIY Segway email storm and I don't really want to do it again. Please direct your segway questions to the internet or to the technical documentation on the original website. Kthx.

That said, the new and improved version has something I've been dreaming about for a very long time: a 1/2" polycarbonate base. But they didn't stop there. They added a 1" polycarbonate handlebar and a not-insignificant wattage of LEDs. It's so bright that I can't even really take a picture of it. With the new handlebar comes tighter, more controllable steering.

ExkateCD
The Exkate electric longboard is cool, but it's heavy and doesn't turn. Jed's team came up with a solution: Make it lighter and more maneuverable. (Duh.) They switched it to lithium polymer batteries (formerly lead acid). They also implemented custom-built dual CIM-planetary-gear-belt-drive-pods. I can't really explain them...they're just awesome. With 2WD and springier trucks, it can take much tighter turns, even under power. But it goes last because it doesn't fly and it doesn't have any lights.

Oh wait...

HSV: Arrows and Fruit

In case you've never seen what an arrow going through fruit looks like in 333x slow motion.

These videos were shot with a Phantom high speed video camera in the Edgerton Center Strobe Lab during a freshman seminar. The lighting came out very well, even at 10,000 frames per second. Everyone's favorite seems to be the one where the arrow misses, taking out the cups but leaving the fruits hanging in mid-air. Newton's first and second law in action.

An interesting side note: the Phantom capture software saved the video in raw 8-bit format at a resolution of 512x256 (exactly 512x256 bytes per frame, no compression). But it added a .mov header. Although Quicktime could play it, my custom video converter tried to extract the frames as raw data. It put the header in as dummy pixels on the first frame, then all subsequent frames were shifted by that amount (so that they looked off-center). The fix was some very simple math:

1. Divide the file size in bytes by (512x256). Take the remainder.
2. Subtract that number of bytes from the file using a hex editor. This is the header.
3. Confirmation that the header ends after this number of bytes:

A wonderful little tag "mdat" (movie data?) at the exact address of the remainder. I love raw video! Compression is for losers.