Replies to This Discussion

Permalink Reply by Michael Pursifull on September 17, 2011 at 5:40pm

From the brief description, I would suspect a CG issue. See the troubleshooting in the manual. Were you in stabilize? Even a highly tuned quad can move about like a hockypuck on ice without a pilot. In 3D if it is not altitude-controlled. 

 

If this were unbalanced props, I would expect vibration. Other issues result in oscillation. Do you know about RC-initiated leveling and auto-trim? It is in that troubleshooting section. I use a cable to find and adjust CG, try to get the arms level from a single hanging point, ideally in line with the XY gyro. 

 

Congratulations on your first flight! I hope you learned a lot to refactor your design, and that your lessons learned come easily and perhaps with fewer broken parts in the future.

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Permalink Reply by Michael Pursifull on September 17, 2011 at 5:41pm

BTW, I'm a fellow newbie, but my first three quads are all custom frames. I'm not too far ahead of you in the experience, so take my input with some caution. 

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Permalink Reply by Andre Lochner on September 18, 2011 at 12:21am

Yes I was flying in stabilize mode. I did not know about the RC-initiated leveling and auto-trim. I will take a look at it. Thanks for the advice.

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Permalink Reply by agmatthews on September 17, 2011 at 11:19pm

Andre,

A drift in one direction is likely to be

1) Wind - quads will always drift down wind without manual or automated correction

2) Level - when you first arm the quad after powering it up it will go through an automatic levelling procedure. If you are not perfectly level it will then try to hold that attitude in flight and this will cause a drift. Use a bubble level  to set you quad level before you arm it. You can also do an inflight level when you get comfortable with hovering flight - see the wiki

3) Airframe - you may have an asymmetry in your airframe/motors causing off centre thrust. you can usually see this if you have a carefull look at the airframe and motor mounts. Centre of gravity issues are similar.

 

To find out what your problem is first try disarming, rotating your quad 90 degrees and rearming it. If it used to drift north and continues to drift north then you have an external factor (ie a breeze). If it now it drifts east (for example) you have an internal problem (ie out of level or twisted airframe)

regards

Andrew

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Permalink Reply by Andre Lochner on September 18, 2011 at 12:21am

Thanks, great idea. I am def going to try it.

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Permalink Reply by Michael Pursifull on September 18, 2011 at 6:11pm

+1, great advice on the rotating 90 degrees!

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