11 April, 2011

Zăganu - 04 Trial times

Since spring time is here and I start to become to anxious about it, I decided to take a short cut and by-pass my DIY controller for a while and use the original arduino version. So I got an arduino nano from farnell and start putting it all together. The arduino board was pretty straight forward to connect and program. I used the latest MultiWii version (1_preter7) and carried on with further configs through the USB port and the GUI software.
Almost ready to fly

I'm not so sure about the center plate design so I improvised a lot, using cable ties and duct tape here and there. I didn't want to let everything loose from the start so based on an idea I found on rcgroups.com, I build something like a test bench. It helps with keeping it on the ground while allowing it some degree of free movement.
 



 First try was quite scary because the sensors weren't aligned with the motors and the tunning loop got crazy. Rest of the tries weren't that scary but not successful either. Using the GUI I can see the accelerometers getting correct readings, even though they turn quite noisy once the motors start to spin, the gyro signals are sadly confusing. The magnitude on Y axis is roughly twice as low as on the X axis for the same amount of movement, if judging from the plot even though the numbers seem to match if monitored on the digital read out. Didn't figure out yet if it's a plot issue or a real sensor issue. Also have some troubles  understanding the logic behind the trimming procedure or the software functionality but that can be solved with some reverse engineering on the code.

Hope to get an actual flight till next post but until then, the work must go on