Monday, September 5, 2011

Quadcopter Tutorial 2: AeroQuad 1.9 Shield

So here's the second tutorial. This will be about how to solder the AeroQuad shield together to make the Arduino more user-friendly. I honestly think it might be easier for you to do the tutorial from the AeroQuad wiki here, but I'll be going through things I had trouble with that they might not completely explain.

So to start, this is what the shield will end up looking like in the end. I'll number all the sections so you know what part I'm referring to when.



Before I get started with that, though, I'll talk about soldering. First of all, when you solder, solder outside or somewhere with good ventilation. This is because the solder has lead in it, which you shouldn't inhale. Also, because of this, wash your hands after soldering because you don't want lead going into your mouth when you eat. Solder on a surface that either won't get damaged or you don't mind getting damaged if you accidentally touch it with the soldering iron. The soldering iron gets very hot, so you don't want to touch it either. If your soldering iron is like mine, it comes with a little ring which you can set it on when you're waiting for it to cool down or just want to take a break. This is a picture that shows what that's for, because I didn't know at first:


Since you're doing light soldering, the soldering iron should be 15 watts. If you look in the previous picture, you can see that mine can switch between 15 and 30. Your solder should be .032" in diameter. This is the thinner type meant for things like this.


When you solder, you should have a relaxed grip so that the soldering iron doesn't move around too much. Don't hold your hand in the air, because that's unstable and hard to keep still.


This is extremely easy once you get the hang of it. There are two ways I've found I could do this. One is to heat up the metal you will be soldering onto with the soldering iron and just touch the solder to it to melt onto it. Another way is to touch the solder directly to the soldering iron, which is much faster but a little harder. If you look closely in this demonstration, you can see that surface tension causes the solder to gather in a cone shape at the base of wherever you're soldering, so it's very unlikely that you will accidentally connect two pieces of metal that shouldn't be connected.


If, however, you do accidentally solder something you shouldn't have, simply touch the solder with the soldering iron. It should melt again and stick to the soldering iron because of surface tension. Repeat this until it's all gone.

Now,for the actual tutorial:

1: 8 pin stackable headers:

In the bag of stackable headers you should have, take out the two longest ones. They should each be 8 pins long. Stick them through where you see the number 1 on the first picture so that the black parts are on the top and the pins are sticking through to the other side. Go to the back of the shield and solder them in there using the tips above.

2: 6 pin stackable headers:

There should be two more stackable headers that are 6 pins long each. Do the same with those, but on the other side, at the number 2 in the picture at the top.

3: Last stackable header:

take the last header. This one is going through the other direction, through the bottom so the black section is on the other side than those of the other headers. I made the mistake of soldering this on last, which makes it really hard as there's not much room once everything else is on. That's why I recommend doing it now.

4: Breakout pins:

Take out these things and break out three segments of 10 pins each. While you're at it, for later, break out one more that's 8, another that's 7, and finally, two that are 6. Now, take the three 10 long segments and put them where you see the number 4 in the picture. The black section should be on the top and the shorter side of the pins should be pointing downwards. Solder these in from the other side. Make sure they're completely pressed into place.

5: Accelerometer:

The accelerometer is the longest sensor. Take it out as well as the pins you broke out that are 8 long. Put the short side of the pins through the bottom of the accelerometer so the circuitry is facing up. Put the long side of the pins through the top of the shield so that the accelerometer is on top. Look at the first picture at 5 for reference. Solder both the bottom of the shield and the top of the accelerometer. Try to keep it as level as possible so that the readings of the quadcopter aren't thrown off.

6: Gyroscope:

The gyroscope is the simpler looking of the last two sensors. Take it and the 7-long pins and do the same as with the accelerometer, taking care to keep it level as you solder it.

7: Last Sensor:

This is the sensor that came with the shield. I don't know what it does, just that it's necessary. Take out the two sets of pins that are 6 long each and put them on both sides of the sensor. Solder it as you see in the first picture and you're done for sensors.

8: Resistor:

Your shield should have come with two resistors. These are the little light brown things with wires coming from both ends. Take the one with the gold, red, green, and purple stripes. stick it through the two holes you see in the picture directly under the arrow coming from the "x". It doesn't matter which way it's flipped. It works the same either way. I find the easiest way to solder these (as well as the LEDs later on) is to stick the wires through and pull them from the bottom in opposite directions so the wires are pointing outwards and holding the top section in place. Afterwards, solder like normal, and break off the extra wires by either using a cutter or bending them back and forth until the break like a paperclip.

9: Resistor 2:

Do the same thing with the second resistor. This one should have gold, orange, green, and brown stripes. Solder it directly under the previous one as in the picture the same way as before.

10: Green LED:

This is simple. Take out the green LED, and solder it in the corner where you see the circle with the flat side. Make sure the flat side of the LED and the flat side of the outline match up. Otherwise, the polarity is messed up and the LED won't work. Solder it in the same way you did with the resistors.

11: Red LED:

This is the same as the green LED. Just solder it in next to it by the next outline. Once again, be sure to match up the flat sides.

Thank you for reading this, and I hope it helped.

Friday, September 2, 2011

Friday

Just wanted to let you know what day it was. Thought I should inform you. So you know what I said about not doing the tutorial because I wanted to do schoolwork? It turns out, it probably would have been more productive to do the tutorial. I got a day's worth of work done in one class after that. I've realized I'm much more productive at school. My personal first day of class was yesterday, and I had gotten a week's worth of work done by first block today. I just have one complaint so far with my classes. My Spanish II teacher has all kinds of questions on her quizzes. True/false, multiple choice, fill in the blank, etc... that's fine. Every teacher does that. I just don't like how the fill in the blank questions are graded by the computer. If you mistype one period or word, you don't get any credit even though you could have gotten the purpose of the question right. This caused me to get a 12/20 or something on one quiz which brought my average down to 90%. That's bad. I'm uncomfortable with anything below 97%.

In my AP Computer Science class, we had an assignment where we had to select a picture chosen by the teacher and describe how to draw it in plain text without saying what it is or what's in it. Afterwards, we had to go to a classmate's instructions and draw what they said. This is what I drew:
This is what it was supposed to look like:
As you can see, mine looks more like two deformed teddy-bears chopped apart with a spike in the middle of a hug. Apparently, that's how you draw a butterfly. So anyway, I thought that was interesting enough to post here. I wrote a "hello world" application for the first time ever in that class too. I've never written my programs like that before. I've always tried to be more original. I wanted to type "System.out.println("something original")" or something, but I've failed in my epic quest to avoid the boring "hello world". So anyway, that's all I have to say. The tutorial will be released when it is. Thank you for reading.