Monday, January 26, 2015

Quad Copter Control Center

The on board control center for the quad copter is what I consider the most important part.  The control center is the nucleus of the whole quad copter, every motor is attached to it.  In addition, the power ports are also attached to the control center.  The main job of the of the control center is to distribute the power to each motor separately.  This allows the quad copter to spin and turn by cutting power from some motors and boosting other motor's power.  Other than distributing power to the motors it also receives the signals from the ground controller and also coordinates add on devices like the compass.
This week I picked out the control center I am going to use.  It connects all the motors, receives signals from the ground controller, and can also hold more add on devices.  I am only going to add one device on my quad copter, the compass.  At the store the clerk explained to me how the compass makes the flying the quad copter a bit easier.  Originally the quad copter had set motors for each directions, meaning that if the quad copter is spun around the the north motor could be pointing south.  This causes the pilot to constantly look at the motors.  The compass would automatically inordinate itself and so the motors can switch positions causing for easier flight control.  The compass also prevents crashes if the pilot loses control.  The ground controller has a panic button which stops the quad copter in mid-air and hovers.

Sunday, January 11, 2015

soldering the baseboard togethor

In order for all the wires of the quad copter to attach they need to be soldered together.  Solder is a metal alloy with a low melting point.  The way solder works is that you melt the solder onto the wire with a soldering iron and join another wire with it.  When they meet the liquid solder should absorb the new wire, and after it has cooled for a few seconds the solder hardens making one continuous wire.  Another application for soldering is attaching a wire to a circuit board(this is what I did).  For a quad copter the function of the circuit board is to distribute the power from the battery to each of the four motors evenly.  First I melted the solder on the circuit board and while it was liquid I put the wire in it, waited a few seconds and the wire is now attached to the circuit board.

To solder all eight wires it took almost an hour.  In my case before I could solder the wires I needed to strip them.  Meaning, getting the exposed wire longer by cutting the wire's rubber coating.  After that, it took almost fifteen minutes to get over the learning curve of how to solder.  Once this was completed it was smooth sailing from there on out.  I also learned that you can never use too much solder because a partial connection could break mid flight and cause the quad copter to have that engine stall causing it to crash, which is very very bad.  This is why you see in the pictures the liberal use of solder.  

In addition to soldering I just got an email saying that my control chip is in for the quad copter and it is ready for me to pick up.  This is the main reason I could not do more with the quad copter than solder.  The control chip is the heart of the quad copter and with out it can't fly.  Now that I have the control chip I can finish attaching the wires and start to program.  Once programming is complete than I can fly.  

As you can see its always better to have more solder than less.