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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.

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 […]

I’ve been working on a code in C to solve the Travelling Salesman Problem using Genetic Algorithms. In the past this problem has been attacked using brute force, simply trying every possible passage. Yet as the size of a dataset rises, the computation time increases exponentially with this method, such that a thousand points can […]

Every year the ESP program at MIT hosts classes for highschool students. Splash is held in the fall, at a time generally assumed to be thanksgiving break. I’ve attended the last 3 years, and loved it. This year however, I’m teaching a class with a friend entitled “The Calculus of Physics”. It will be awsome, […]

After a few nights of work, I had a hovercraft I was proud of. Beautifully crafted from plywood, a 2×4, and Visqueen, I was certain it would provide hours of hovering enjoyment.
Hah.
My test versions worked perfectly. I figured that the physics would scale up, and all would be great. Turns out, propellers don’t scale up. […]

I recently whipped up some drawings for a easy-to-build two person hovercraft. I’m now in the buildling stage, and it’s nearing completion! I should be able to ferry 350 pounds around, using a 24″ propeller and a tractor starter motor for thrust.

I installed a ball valve to make it easier to spray in the AquaNet. My friend Mike either did a crazy fluid computation in his head or accidentally came up with an amazing method for spraying and loading the potato cannon. With the new method, we hit 386 feet!