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Today I did a lot of math regarding the lift of a non-airfoil wing. From the math and review of the videos, my best bet is that we aren’t properly maintaining the right angle of attack during takeoff. The leading edges aren’t near strong enough either, but that’s something I can’t fix (if anyone knows […]

This post is divided into two parts: Things I’ve done recently, and things I’ve acquired recently.
Events
Last Sunday I was up at 6am to do communications for the MS walk in Worcester. I didn’t actually need to do anything.
This Sunday I was up at 5am to get to the MIT Swapfest. Usually Ken and I come […]

I heard back in the day of someone building a hang glider from a tarp and bamboo… While I went slightly less ghetto, this Winter break I built a hang glider with the help of several friends. The thing is quite… well… take a look at the project here.

A while ago I posted regarding the network when I moved into my apartment. This winter break we finally got around to working on things and taking it from a cluster of gross to a pretty little network of lights. Internally, we have 3 separate IP segments, bridged by our Cisco 2500 routers. Additionally, […]

I’ve been working on my CNC mill over the past month. It’s based on a small manual mill made by Proxxon. I have 3 nice unipolar stepper motors, one on each axis. The motors are controlled by 3 L297s from ST Micro (these are REALLY amazing by the way…) to 12 TIP102 transistors used as […]

If you’ve ever been to a supermarket in a city, you’ll have likely seen a lock on one of the front wheels of the carts to prevent people from stealing them. A friend and I managed to make a transmitter so that we could the carts would lock when I walked by with the transmitter […]

I’ve collected 65 flash capacitors from disposable cameras over the past months and put them together. Last night we used them to make big sparks and such… see it here.

In browsing around, I found JTrack3D on the NASA, a basic 3D satellite tracker. It works well enough, though it only lets you use predefined vectors. I’ve edited it so that you can use your own. Take a look at JackTrack3D.

Finally got the whole page for the goKart and the logic probe.

To find something to do with my handy-dandy logic probe, I threw together a very simple square-wave oscillator using a 555 timer and some simple components I had lying around. You can only see so many square waves before you get bored, so I decided to see how fast I could make a 555 go. […]

I got the Logic Probe built, and it even looks almost cool… as soon as I get a little time I’ll poke around some chips and see what happens. Until then you can check out the page with a basic description of it.

FINALLY the Low Altitude Temperature Profile page is finished, and includes all the details of the project. The Electric Kart page should be up soon.

Tested the rocket today for the big event tomorrow… let’s just say that thing went downhill after the rocket entered the trees at about 300 MPH. I think I’ll be able to get the kinks worked out for tomorrow…

Let me start by saying that this is easily the largest undertaking I’ve yet done.
I’m working on an experiment to make a mathematical model of the temperature at low altitudes, and how it changes as the sun warms the earth. I’m basing the model around the heat equation.
I plan to launch around 6 rockets, starting […]

Ever since my introduction to computational fluid dynamics last year, I’ve been reading several calc books and tutorials to learn Partial Differential Equations. By no stretch of the imagination am I a master, but last night I finally succeded in solving the Heat Equation.
Not only do I now understand initial and boundary conditions, but I […]