Infinite spinning quad + compass issues

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joebob85
Posts: 8
Joined: Mon Feb 23, 2015 9:04 pm

Infinite spinning quad + compass issues

Post by joebob85 »

So I have a strange problem.

When I apply throttle to the system, All 4 motors start fine, but then the front right and rear left motors PWM signal starts to drop...and drop, until it hits 1300 (from 2000) , which is my min throttle setting. As far as I can tell,the copter is attempting to continuously rotate, but I cannot figure out why. Acc, Gyro holding fine, compass has been calibrated multiple times but I can never get it to track the heading properly. It tends to move in the opposite direction first, then track back to (almost) the proper heading. Also, is Y on the compass tracking 90 degrees out? Any attempt to fly leads to instant flip overs. So confused....Help?

attached are before and after screenshots of the config
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FengShuiDrone
Posts: 234
Joined: Wed Dec 24, 2014 1:20 am
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Re: Infinite spinning quad + compass issues

Post by FengShuiDrone »

Don't worry about the motors slowing down when the quad is sitting still and not in flight. It's supposed to do that. I'd be way more worried about the flipping over on take off. Right away I would suspect that your motor wires or receiver wires are not hooked up properly. Double check all of that and make sure that your props are correctly installed and all rotating in the correct direction. Go back and read all of the beginners sections of the online info until it starts to make sense. Also, 1300 min throttle isn't right. You most likely need to center up your TX using endpoints and subtrims. You will find that info in the beginners stuff too. Your throttle should be more like 1000 min, 1500 mid, and 2000 max. There's a boatload of endpoint and subtrim videos on YouTube probably for your TX. Your question about "Y" on the compass. What is "Y on the compass"? The compass has N,S,E, and W, not x and y. If Y is the yaw reading on the graphs section under mag then yes, there is some sort of problem. Is the FC mounted facing forward and in the center of the quad? Is the graph acting funny when the motors are spinning or is it just sitting there static. More info on what you are flying would help.

joebob85
Posts: 8
Joined: Mon Feb 23, 2015 9:04 pm

Re: Infinite spinning quad + compass issues

Post by joebob85 »

FengShuiDrone - thanks for the info on the motors, that was driving me crazy.

Running MW 2.3 on ProMini with GY-80 IMU (L3G4200D, ADXL345, BMP085, HMC5883)
Turnigy TGY9X transmitter + 9X receiver
Turnigy Plush 25A ESCs, Avroto M2814-11s motors, 10in props

Double checked motors + wiring, all is correct. I did discover one problem, the Z axis on the compass was reversed, so MW though it was upside down at all times, far as i can tell. Fixed that for now, however I am tempted to just remove the compass entirely , since im not using nav on this set up. Will that affect flight performance considerably?
TX endpoints and subtrims are all set correctly, full range of 1000-2000 possible.

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