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Permalink Reply by James on April 30, 2012 at 5:26am

My hexa has an AUW in the region of 2.3Kg - with 880KV motors, 12x4.5 cheap (rctimer) props and a 400g camera about 200mm below the rotor plane i tuned RATE P down to 0.08.

 

now with APC 12x3.8 props i have lowered STAB P to 3.7 and upped RATE P to 0.092 with RATE I 0.022 and RATE D 0.006, still plenty of room for improvement but perfectly acceptable.  your frame is obviously different, but i hope it serves as an example.

 

james

 

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Permalink Reply by James Dinh on April 30, 2012 at 8:23am

Thank you.  I will try this and see.  I hope this solves the problem of why my hexa tips over when trying to lift off.  I have done all the motors and sensors tests in CLI and all the motors rotate in the corrects direction with the correct pusher and puller props.  All the APM set up and calibration seems to have been done correctly, yet the copter still tips over.  1st time it tipped backwards on #4 arm ( my hexa is a + formation), 2nd time after tuning rate p down to .12 (from default of .14) it tipped forward on to #1 arm.  Anything I've missed?  I'll try tuning rate p down to .08 and see what happens.  If you have any other suggestions I could definitely use it.  Thanks.

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Permalink Reply by James Dinh on April 30, 2012 at 9:17am

I think I've stumbled onto why my hexa tips over on takeoff.  I plugged my motors/esc into APM in the wrong order.  Going clockwise I plugged motor 1 into APM output 1, 2 into 2, 3 into 3 etc.  Finally stumbled onto the wiki page showing me the correct order.  Hopefully, this solves the problem.

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Permalink Reply by philip desborough on May 1, 2012 at 3:51pm

bump

 

must read

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