Monday, November 30, 2009

Engineering, Mythbusters style

With sites like Hulu making it easier than ever to watch TV online, I've spent a fair amount of time in between classes catching up on shows I've missed on my computer rather than my TV. I've also started watching some shows I may not have watched had it not been as easy as searching for it online. One of these shows is Mythbusters. I used to watch the show a little, but only if it was on when I was looking for something to watch. Now, I've kind of become an addict, and I'm only worried for when I run out of episodes.

What I've noticed is that Mythbusters is really all about engineering. It's not engineering in the traditional sense, but a lot of the show revolves around problem solving, ingenuity, and (very) creative thinking. Mythbusters is as much about science as it is about engineering. Sure, they conduct a lot of experiments, but in order to set up most of these experiments they usually have to build something that's never been built before, or at least build upon their knowledge of the subject at hand to find a way to test the sometimes crazy myths.

I've already seen some things on the show that I can relate to at school. In one episode, they were testing the myth that a skydiver with a faulty parachute landed on a see saw, rocketing a small girl up 7 stories and landing her safely on the top of a building. The first innovation the Mythbusters made was to use a heavier mass falling from a shorter distance that would impart the same force as a grown man falling at terminal velocity. When the weight fell on the see saw, the myth was busted when the see saw was completely destroyed, launching the girl only a few feet instead of the desired 7 stories. Adam and Jamie recognized that the energy from the falling "skydiver" was being used to bend the metal see saw, and not being transferred to the girl as kinetic energy. They solved this problem by building a heavy-duty see saw. First, they modeled the see saw on a computer program which allowed them to artificially test the strength to see whether or not it could withstand such a large impact. This reminded me of ProE Wildfire, which, as a mechanical engineer, I have been using to model parts and assemblies that can then be sent to manufacturers. After their design was shown to work, they made a V-shaped see saw. Each end of the V was connected to the other using a high tension nylon rope with a very high breaking strength. When the skydiver landed on this see saw, the energy would not be absorbed by the nearly indestructible see saw, but rather transferred to the girl who ended up flying 13 stories into the air. Even though this see saw does not exist in real life, and the chances of this happening are extremely improbable, they proved the concept that, given the proper conditions, the myth is true.

What I learned from this myth and from watching the show is that sometimes you have to think beyond what you already know to be truly innovative. The see saw needed for this myth simply did not exist, so they thought outside of the box and came up with one they knew would work. They took one of the most simple machines, the lever and fulcrum, and improved it to the point where it was strong enough to withstand the impact of a grown man falling at terminal velocity, and transfer energy efficiently. That sort of ingenuity, coupled with an impressive knowledge of the scientific and physical world, can lead to some really remarkable ideas.

I feel that Mythbusters tries to hide the fact that they are an engineering show. They rarely use the term "engineering," and while most of the hosts actually worked in special effects for movies, they clearly demonstrate they are extremely skilled engineers. While it is evident that not much of what they do is practical in the real world, the processes they use and the thought they put into their designs are very applicable to the field of engineering.

Tuesday, November 3, 2009

more on our steam car...

So, it's been awhile since we actually did the steam car competition, but I figured I should give an update on how it went.

It started out kind of rough. We over-fueled the car for the first test (fastest start - whose car could make three revolutions of the turbine the fastest), which literally put our project up in flames. This wasn't a huge problem, but the rubber band drive shaft melted, and we lost that contest. We simply replaced the rubber band and we were good to go for the speed test. There were two brackets for this, and we were first in all but one race during the first bracket. For the second bracket, we were up against a team that had done equally well in their respective bracket, but we ended up being faster (which was a pretty big surprise to us). Here's a video of us winning the last race.



In addition to winning the actual race, we also came in first for the "Meanest" car (thanks to the intimidating wings we added at our last meeting), and we also placed in the competition for best design.

I think a lot of this competition was luck, because we simply didn't have enough time to properly test how we could modify our car to make it consistently faster or start up quicker. The fastest start competition was almost entirely luck, as it primarily depended on how much water you had in the boiler, and the subsequent ratio of how quickly that water could come to a boil and the vapor pressure the steam could create. All in all though, I think the fact that everyone's cars worked as well as they did proved we were successful with our projects. I'm really looking forward to the next project, as we'll have enough time to test our Arduino and make sure it works as smoothly as possible.