Member Since: July 1, 2010

Country: United States

  • At $30 a key, I don't see a lot of people building full size QWERTY layouts. For that kind of money you could buy a 3D printer and make your own, which would include a full size space bar.

  • While I was in college about t&$@#e years ago, I spent a Christmas week at a cabin in the woods. I knew I would have little to do during the week, so I came prepared--I brought with me a considerable amount of balsa and basswood, cardboard tubes, glue, and X-Acto blades, so I could spend my time designing and constructing a model rocket. The design was quite complex; it was to launch vertically, as normal, but with the ejection charge the body would lengthen and wings would extend out so the craft would glide back to earth. The most difficult part was getting the balance right so that the center of gravity would be in the right place for the ascent, but then would shift just the right amount to facilitate unpowered flight. I carefully fabricated 1.7 bajillion parts and glued everything together; I tested its flight characteristics, as best I could, by tossing it around the room in various configurations.

    Of course, the woods is no place to launch a flying torch, so I had to wait until the last day to send my creation on her maiden voyage. I had a location chosen--a field near my route home. It was on a farm, but unsown for the winter, thus presenting a vast expanse of non-flammable dirt where I could be fairly certain of recovering the glider.

    The fly in the ointment was the breeze across that wide, flat expanse. With no terrain to dampen the wind, I had some stiff gusts as I walked out to the launch location. They weren't especially frequent, and I figured I had a pretty good chance of getting the rocket aloft; but as I prepared to hit the button, along came a gust and knocked the whole thing over. I brushed off the dirt, set it upright, and readied to push the button; again, a gust of wind toppled the thing. So I got smart. There was a utility shed not too far off, so I relocated to the leeward side of the shed. Now I could be certain the wind would not blow the launch pad over while I was trying to set it off. I readied, pressed the button, and waited...after a couple of seconds, I heard the familiar hiss as the engine ignited, and the bird took flight.

    It got just to the elevation of the utility shed. Suddenly, clear of its windscreen, FOOM! The rocket was hit full force by the wind. It immediately made a 90 degree turn in the air...and of course you geometry nerds know that when a vehicle is traveling vertically and makes a 90 degree turn, it isn't going vertically any more.

    The next few seconds all happened in slow motion. Traveling horizontally, the rocket's path was now curved downward by gravity. With plenty of fuel left to burn, she arced down toward mother earth, nosing gently into the ground and began plowing a new path through the fallow soil. Turns out the aerodynamic characteristics of such a vehicle are unsuitable for subsurface operations, and the body began to shed its 1.7 bajillion pieces in order to improve the vehicle's dirt-navigation capabilities. After what seemed like a month but was probably closer to five or six seconds, the propellant was exhausted and the rocket came to a stop.

    Of course, those of you who have built and launched model rockets know that the engine was not yet spent. We had entered the delay phase, where the engine emits smoke without providing propulsion. The fuselage, stuck in the dirt at a disconcerting angle just a few yards from where it had been launched, spat a cloud of smoke for an interminable period as I braced myself for the coup de grace: the ejection charge. It had been designed to displace a lightweight nose in flight; but the nose was immovable, which meant the burst would displace the comparatively heavy fuselage instead. It did so, quite spectacularly.

    The scene was like a miniature disaster area, like the aerial shots you see on the news of a plane crash: a swath of blackened earth terminating in twisted wreckage with wisps of smoke rising from unrecognizable chunks of debris. Delicately carved bits of wood were strewn randomly about--a part of a wing here, a tail fin there. It was quite the catastrophe, in miniature.

    All in all, it was a pretty good vacation. But it could have ended better.

  • How much current can the IO pins supply? I want to be able to drive some small relays to control some appliances and I need to know if the IO can power the coils directly or if I need to add an interposing FET.

No public wish lists :(