3 Leg Landing Gear. Could it be the problem?

Navio / Edge Hardware
1

Hi guys!
I am Mariel. My team and I built an octocopter. We chose a frame that has 3 legs, set it up to be OCTO + and placed the legs on arms 1, 4 and 6. (Please refer to the image below)

MOTORS_Hexa-octo-y6.jpg800×1200 246 KB

During flight testing, our octocopter always drifts to the right or on the direction of motor 8 and 4, instead of a vertical navigation. It didn’t stay in place during stabilize mode. All hardware configuration were performed including accelerometer and compass. Motors were also properly calibrated. We also make sure to fly it in a flat surface (guided by mission planner).

Is it possible that the 3 leg landing gear might be the cause of the drift since the weight distribution is not equal? If yes, what is the proper setup for a 3 leg landing gear? Also, if any of you guys have another solutions about this problem, please do comment. Thank you in advance.

2

Hi,

you should try this:

http://copter.ardupilot.com/wiki/autotrim/

1 Like
3

Hello. Thank you for the reply. We will try your suggestion as we get back to school and will give update about it. :smile:

By the way, I have another question. As we calibrated the compass, the offsets displayed on the Mission Planner is -200 as the first value, like -200, -50, - 40. We tried re-calibrating and the first value is always -200. Is that okay? If it is not, is it better to use compass learn instead?

Thank you again for your help.

4

Your compass offsets are not to high.
Do not use compass_learn on a multicopter. A copter can fly in any direction without changing yaw orientation. If I am not mistaken compass_learn uses the GPS track as a reference and this could be misleading, if the copter is flying backwards or sideways.

5

Our octocopter is working properly now. Thank you so much for your help! :smile: