Here's another quick quadcopter update.
I'm still waiting for my motors and ESCs to arrive before I begin building up the frame. They should be here this week, hopefully sooner than later.
I have connected the Accelerometer/Gyro sensor to my Arduino. It took a little bit of work, but I now have good data coming from the accelerometer. The gyro seems to have an introverted personality as I have not been able to get it to communicate. I believe this is due to it needing a 3.3v I2C buss and the Arduino provides a 5v buss (although the accelerometer runs off of 3.3v, it can accept a 5v buss). I have ordered a level translator to solve this problem. Hopefully the 5v buss didn't fry the gyro.
The coding is coming along well. I estimate that I am over 3/4 of the way done, and I believe the most difficult tasks are completed. I have made up a flow diagram to show my control loop.
Quadcopter Control Loop
Once I am able to get both sensors working, I will be able to start testing the code and debugging more.
At this point the compiled code is arround 9k in size, so I am optimistic that when finished I will easily fit in the 30k that's available. I will be looking at my memory usage next to make sure I'm not going to run out of the 2KB SRAM I'm allowed. Right now I estimate my loop time to be 15ms not including the time to scan the RC inputs. I may use a second Arduino just for watching the RC inputs as they will only come every 20ms and if I start watching for them at the wrong time, I could waste a huge amount of time doing nothing. I would then transfer the the inputs from the second Arduino to the first through the I2C buss, which should only take 0.2ms.
That is all for now.
Phillip
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