kakostacbhp’s Blog

I feel like we’re getting down to the wire now. But I’ve already got so much stuff to do… Time management should never be a dump stat.

I did surprisingly well on those two quizzes, even if part 2 came as a shock, and if the rest of the class did too then all the better for everyone. On the other hand, I managed to be rather thoroughly fooled by constructor and destructor output. Better luck next time. I’m excited and a little nervous about the group projects, and very happy to be putting some effort into the final project beforehand, especially since I’ll miss the first day we talk about them!

And finally, I’ll throw this out as a discussion topic: textbooks and the internet. I don’t agree with everything, but the blog author made some very good points. Much as I enjoy paper (it’s renewable AND recyclable, unlike electronics), nobody wants to lug around 20 pounds of textbooks. Nobody wants to pay upwards of $500 for 20 pounds of textbooks, either. It’s even worse when you know you’ll never read them. The author encourages classrooms to adopt electronic media instead, arguing that it’s cheaper, more portable, and not nearly as blandly PC. He even goes so far as to suggest eliminating textbooks in some classes and making it necessary for the students to find reading materials themselves. Great ideas, and I would love to see them implemented.

Go see the Onix in the video and the picture.

Anyways, it seems this guy, Shigeo Hirose, makes lots of new and creative robots. The Onix I mentioned is actually a swimming snake called Active Code Mechanism R5. Not sure what its purpose is, but it’s very sleek and elegant. (On a side note, this is kind of how I imagined the submarine from 20,000 Leagues Under the Sea. That should tell you something about me.)

For functionality, there’s the Elastor, which looks like a slinky arm with a claw on the end. Good for reaching things that people can’t, as demonstrated in the video. Then there’s Genbu, an “articulated multi-wheeled mobile robot” that’s great for getting over debris and rough terrain with its many wheels and metal-ridged tires. Rough ride, though. The Soryu is somewhat similar, but it has treads and is very good for vertical paths. The SMC Rover is a planetary exploration vehicle that can detach its legs and send them off on missions. The TAQT Carrier and the Vmax Carrier would be so much fun as actual modes of transportation.

I suppose the SoftGrip and the Roller Walker could be useful somehow, but it’s even better just to watch them. Especially the Roller Walker – the first roller skating robot? And the Tirtus III, which is basically a velociraptor! It’s so cute.

With all the crazy kinds of stealth and camouflage that UAVs are capable of, it seems kind of silly that they’d be vulnerable to plain old hearing. But UAVs are flying lower and lower as the kind of missions that they’re given are changing, so aeroacoustics researchers are trying to find ways to make UAVs quieter.

Their first task is to figure out what part of the vehicle is making how much noise. They had to find a way to separate the engine from the propeller to determine the amount of noise coming from each. Unfortunately, removing the engine would also remove the propeller coolant. Other cooling methods typically add even more unwanted noise. So the researchers had to find a substitute cooling method and a different load for the engine to spin.

Another difficulty they had was testing engine performance and acoustics simultaneously, since they didn’t want to reduce performance too much in favor of less noise. Tests had to be done on the ground, in flight simulation/acoustic chambers, and in the field, where the atmosphere and weather changed the acoustic signature.

And finally, they had to figure out ways to reduce noise without changing the UAVs infrared and radar signatures.

Despite all these difficulties, the aeroacoustic researchers have come up with some specific ideas that they believe will reduce noise and now they’re constructing prototypes to see how the data holds up.

I’m pretty sure I understand pointers. They’re simple enough, even if the syntax isn’t always, especially when they’re used with objects. References are a little muddier. I guess I just need to remember that they’re meaningless by themselves. You cannot manipulate the reference itself, only what it refers to. Listings 9.6 and 9.7 were helpful for that. When I was writing the code, though, I kept getting confused. Since the pointee is named *px, I started thinking that referenced variables would be called &rx. It doesn’t help that you can write the declaration as int &rx instead of int & rx. I’m going to work some more with references to try to get myself straight, but other than that, things are going well.

The $64 dollar question: book or no book?

It would definitely be nice to maybe get a higher grade but to be honest, I really don’t care that much. I’ll go with whatever Jaclyn decides. I don’t think that having the book for five minutes will make a difference if you don’t study the material in the first place. And the book doesn’t keep you from making stupid mistakes when you think you have something right. I dropped a lot of semicolons in that quiz, I forgot std::cout before the std::endl, and I wrote the wrong symbol for <= a few times. Aside from those three things, I only missed one question. And I didn’t catch any of them by using the book.

So… let’s just see how this goes.

We probably all know those people on Facebook that have ridiculous numbers of friends. I’ve seen someone with over a thousand. But it seems networking sites only increase our capacity to keep up with people to a certain extent. The Dunbar number (150) is one of the theoretical limits for the size of a stable social network. There have been other estimates, some almost double the Dunbar number, but the idea remains that there is a limit.

Social networking sites, far from allowing us to exceed this limit, seem to encourage passive information gathering rather than interactive communication. The statistics in this article for the average user are surprisingly low. Anyways, take a look, see what you think.