Mad Science

IT LIVES!!! Well...I'm sure it would if I were a biologically-minded mad scientist, anyway. If you look back a few posts, you'll find that I planned on building a theremin and writing a plugin for calculating multilegged robot gaits in Blender 3D. Neither of these has happened. However, mad science finds a way, and I have two projects that are (mostly) done now:

• IR Goggles: Engineers learn that there is no such thing as perfection. Specifically, for my application, there is no such thing as a perfect band-pass filter. The human eye can be thought of as a system that produces a significant response to electromagnetic radiation with wavelengths between 4 and 7 hundred nanometers, peaking at about 550nm (green light). This band of the EM-spectrum is usually called "visible light" because, well, we can see it. The response is a curve, though. It's impossible to get a sharp cutoff in any system, and that includes our eyes. Thus, with a powerful enough source and some way to block all the "visible" light it becomes possible to see light classified as infrared (around 720nm). Your eye produces a very weak response to near-IR light, but it's still there and by blocking out all the visible light, we can actually see IR light. I don't have quite the right lighting gels, however. A friend had extra gels that she gave me and she had the correct "Primary Red" but not "Congo Blue". I tried it with the "Royal Lavender" that she had, but that doesn't actually block much more red than the "Primary Red". Thus I have very dark red sunglasses until I get my hands on some actual "Congo Blue" gels or equivalent.
  
• Tesla Turbine: Nicola Tesla was a mad genius. Probably my favorite historical figure, Tesla was a brilliant man who really had some great ideas. Many know him as the invertor of the Tesla Coil and pioneer of AC electricity, but he also built other things. The Tesla Turbine is a design for a bladeless turbine that uses a nifty property of flowing fluids known as the Boundary Layer Effect. In short, when a fluid is flowing across a surface, the molecules against the surface don't actually move. The next layer of molecules moves slowely and each further molecule moves faster until you reach the full speed of the fluid. Tesla, although fluid dynamics was not a field that we knew much about at the time, observed this and used it to make a pump to move mercury. He thought it was friction at first, but soon realized it was something else. He later ran it in reverse, pushing fluid through it in order to make it spin. The idea here, is that you take a bunch of disks and stack them up with very little space in between. You then put the stack in a cylinder and squirt a fluid on a tangent to the edges of the disks. The fluid "sticks" to the disks because of the boundary layer effect, transferring some of its energy to the disks. As it loses energy, it travels more slowly, so the radius of the circle it takes around the disks shrinks. It eventually spirals all the way to the middle where it reaches an exhaust drain. I made mine from CD's glued together with neodymium magnets and a small CD spindle. These turbines produce high rotational velocities, but rather low torque. I suspect that is the reason you never see them in modern applications even though they are more efficient than conventional turbines -- you normally want high torque.
  

Pretty good for the last two weeks of living here. I'm going home next Friday, but we're almost entirely packed right now. For those of you wondering why on earth someone would choose to live out of a bag in South-Central LA for a week (where you can't really go out to do anything without fear of getting shanked) I shall...well, at least rationalize my insanity. The apartment building tosses everyone out for 10 days at the end of summer. Why this is, I do not know, but Chris, Megan and I got some storage pods delivered and piled almost everything in the apartment into them. We are left with the one or two bags that we're taking home when we leave and the food in the fridge. Incidentally, this is why I don't have pictures of the tesla turbine being built -- they're on my desktop computer. It's out of commission until I get back to Mudd in August. I'm so bored this weekend....