Monday, February 8, 2010

Il Gennaio

This January I spent three hours every weekday taking Italian I, that I will hopefully get to use if I am placed with a host for the summer through the MISTI Italy Program. Learning to count and say the days of the week was a welcome break from solving Navier-Stokes equations and writing transfer functions. Our Italian teacher was fun so the time went by fast. Jose and Kristen were in the class with me too. That made things easier since our rooms are all within 10 feet of each other in Spanish House. If things work out I'll have some travel buddies. We just finished how to say things in the past tense by the end, so hopefully I will remember some of it. I had to introduce Kristen to the class as an assignment, which is a pretty good representation of the rudimentary things I can say. I don't know how to put accent marks over some of the e's on here though so it might translate wrong.

"Vi presento Kristen Pena. Kristen e nata la trenta guigno di un millenovecentonovanta di New Jersey. Ha diciannove anni. Ha i capelli scuri e le occhi marroni. E portoricana e ha due grandi fratelli, Peter e Patrick.

Studia l'ingegneria meccanica e l'ingegneria biomedica. Gli piace ballare e dormire. Balla molto bene. Non piaccino i ragni e non ha animali domestichi. Ascolta musica R&B. E studiosa e facilone. I suoi colori preferiti sono verde e viola."

The weirdest thing about Italian is that "ci" & "ce" are pronounced soft like cheetah, but "ch" is hard like cat.

During the last week I was supposed to be in two classes at once since I was signed up for 2.670, an introductory class to machining that MechE sophomores take. I also came down with the worst stomach flu I've ever had, so I was out of commission for part of the week. Nonetheless I was able to finish the project we were supposed to build, which was a DC Motor.



It was a horrible motor though, mine only reached 1200 rpm, while most reached 3000 or 4000 and fastest being 7900 rotations per minute. I was just happy it spun. I didn't design any of it, we were given instructions and could make a couple decisions on how to optimize it. I lathed one end of the cylinder, put the holes through it, then weaved the wire through. Then I drilled & tapped the holes for the screws in the case with the drill press and mill. We popped in ball bearings on the ends to hold the cylinder and glued magnets to the side. Finally we put on copper tape, soldered the wire to it so it would conduct when a battery was hooked up to the paper clips, and sliced the tape into four sections.

When you hook up a battery to the paper clips it sends a current through the paper clips, copper tape, and wire, which produces a magnetic field around the wire. So for example the wires running on the bottom in the picture will have a current running towards the left looping back around towards the right through the wire on the opposite side (you can't see it here) to the other paper clip which is at a lower voltage. Since this magnetized cylinder is already in the magnetic field created by the permanent magnets, one side is pushed up and the other is pushed down. Once the cylinder rotates enough, the gap in the copper tape disconnects the voltage conducted through the paper clips then reconnects to a different segment of tape sending the current in a new direction so that the motor continues to spin in the same direction rather than oscillating back and forth.