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Fibonacci

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Not elegant, but effective:

#!/bin/bash
n1=0
n2=1
c=1
while [ 0==0 ]
do
  s=`echo “$n1+$n2” | bc`
  count=`echo “$c+1” | bc`
  echo -e “$c\t$s”
  n1=$n2
  n2=$s
done

Threw it together to demonstrate to Boy Wonder how to devise the sequence. Actually, this is the one I started with in pseudocode on the side of the refrigerator then it morphed into the one above to make it work in bash:
n1=0
n2=1
do
  result=n1+n2
  print result
  n1=n2
  n2=result
loop
Serves very little practical purpose other than to learn and see the relationship of numbers.

And Now, For Something Completely Different…

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I love technology. Click through for more awesome quadrotor video from the U. Penn GRASP lab:

Yes, quite cool. Here are a few ideas:

  1. More quadrotors!
  2. Adjust the flight pattern to combine rotation and all three directions of travel in one or two combined movements instead of many separate movements. This one might be a bit tricker to implement effectively.
  3. Give them the ability to self-dock in a series of charging stations. Probably trivial to make them dock at a particular location (like one of, say, three charging stations). But to have a battery that can be charged quickly enough to be worthwhile — that might be somewhere in the future.
  4. Give them more parts to build larger, more awesome structures — like a shrine to our Robot Overlords.

Science Awesomeness

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Kids at a Lebanon, Ohio Christian school participate in launching a ballon-cam into the upper atmosphere.

http://www.youtube.com/watch?v=T89AwNredKI

Very nice that the kids get to participate in a bit of exploration like this.

This isn’t the first of these that we’ve seen — in fact, there have been many of them in the past few years alone.

It’s curious, though, that with as many amateur balloon-camera launchings as we’ve seen recently, it appears that nobody has done anything to correct or limit the platform spin.

So, here’s an idea for the next team that tackles one of these: add a pair of small mechanical gyros with their axes parallel to earth and at right angles to each other to limit yaw/pitch and spin. That should limit and possibly completely eliminate the spin of the camera platform without introducing much vibration or too much additional weight.

Still — it’s science, and it’s awesome.

Think First, Then Speak

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An old one:

The usher noticed a man stretched across three seats in a movie theatre, he walked over and whispered, “I’m sorry, sir, but you’re allowed only a single seat.” The man moaned, but did not budge.  “Sir,” the usher said more loudly, “if you don’t move, I’ll have to call a manager.”  The man moaned again but stayed where he was. The usher left, and returned with the manager, who, after several more attempts at dislodging the fellow, called the police.

The cop took a look at the reclining man and said, “All right, son, what’s your name?”

“Samuel,” he mumbled.

“And where’re you from, Sam?”

“The balcony.”

In all things in life: stop, think, observe, plan.