May 23, 2011

Journal Entry #7

Busy weekend. To start, I have soldered together the remainder of my components - while not yet tested, I'm confident they'll work. The much bigger thing accomplished, however, was the construction of  a track for my car.

To start, soldering. The last time I used a soldering iron, i burned myself and destroyed a sensor because I didn't have enough hands. I decided to rectify that by acquiring another pair of hands - a simple little stand that is able to hold whatever I'm soldering while I solder it. It was very useful, and I was able to solder my motor driver and ultrasonic sensor very quickly. What also helped is that I got a new soldering iron, making sure that it would be hot enough for what I needed to use it for. And it works great.

But the much bigger project was my track. I've been worrying a bit about how I'm going to construct my track, as it needs to be high enough to be read by my sensor, but also has to be able to stand on its own. I've changed my mind frequently while considering my track -  cardboard, poster-board, wood, cardboard again - and thought I had a great solution when my mentor recommended just buying cut pieces of 2"x8" lumber from Home Depot. However, I soon learned just how heave 2"x8"s can be, and with nothing to keep them upright, they could easily fall down and kill my car. So while that was the easiest solution for my track, I feared that it might not be the best.

I settled on another idea offered by my father: take thinner wood (which can't stand on its own but is light) and put supports on it to keep it upright. I found some nice long pieces of molding (the stuff at the base of walls) sitting in my garage that would work. For supports, I ran out to a store and picked up some shelving supports. I spent the next several hours manually sawing my wood into more manageable slices, drilling holes, and sticking a shelving support on each side of the board. While this approach certainly took more time, my result is a very decent-looking, and very sturdy, track.

The design of my track consists of ten pieces of wood on the outside with one piece down the middle. The perimeter of the track at the most will be 38 feet - this is slightly large, but gives my car plenty of room to work with. Each side is made up of two 5-foot pieces, and the ends are composed of three 3-foot pieces. I am able to adjust the size of the ends, as I am not certain how much room my car is going to need to turn. As I progress more on my code, I will set up my track and try to get my car to run around it. We'll see how it goes.

With that large part done, the remainder of my time is being spent coding. Code, test, repeat. By the end of this week my car will be fully functionally awesome. At which point, I'll certainly upload a video of it working.

So until next time.

Next: Journal Entry #8