Why does my H quad flip over? HELP me please!

FliteTester

Junior Member
I think I've done everything and all it does is flip over.

NTM Prop Drive 800 kV motors 4x
Afro ESC 20amp 4x
Hobbyking i86 Lite Contorl Board (KK2 was out of stock)
nano-tech 3300 mah 3s lipo
TGY 9x tX and rx
Knuckle H quad frame

Calibrated my ESCs, once manually, once through the control board (not sure why). I did the Stick Centering function on my i86 Lite Control board. All the motors and props spin the correct way. Everything is plugged in correctly.
I got my TGY 9x set on Acro-mode. not sure why?

Anyway, it pretty much starts to take off and then instantly flips over.
Obviously, I'm a total beginner. just looking for some pointers

First build, please help.

quadcopter.jpg
 
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xuzme720

Dedicated foam bender
Mentor
Usually flipping is caused by having one or more axis' reversed on the radio/FC, or having ESC's mixed, like motor 1 plugged into where motor 3 is supposed to be.
 
Had the same issue the other day and despite me being sure that the motors ans props were all spinning the direction they should be, two of them were not. Check the motor rotation and that the props suit the direction the motor has to turn. That's what solved my problem. Can't offer more advice I'm a noob lol
 

Craftydan

Hostage Taker of Quads
Staff member
Moderator
Mentor
From a quick glance at the photo, followed by a check of the manual, all 4 of your props need to be swapped - if they're blowing down, theyre spinning the wrong direction.

For the quad x4, the front and back pair should spin such that the inside blades spin toward the center. If these motors spun that direction, the props would blow air up instead of down. There's still a chance something else isn't right, but that part is visable.

As for your setup confusion, the tx is set to acro mode and the ESCs are calibrated through the board for the same reason - the control board is flying the copter, not you. Even with a board as simple as the i86, the board is intercepting the basic control commands and making complex decisions to mix that signal among all 4 motors.

So what does that mean to us? We need to keep our radio inputs generic , and setup our ESCs to the min/max for the board. Dual rate and expo on the radio is not bad... Possibly even setting up a throttle curve if you know how (and *after* you've flow it a while), but I wouldn't recommend much more setup in the radio, because you *want* to offload as much of the piloting into the control board as you can, especially with a board as basic as the i86.

BTW, Welcome to the forum!
 
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cranialrectosis

Faster than a speeding face plant!
Mentor
Good catch, Dan.

He's right. All four of your rotors are incorrectly installed. If the props are blowing air down, then all four of your motors are also spinning the wrong direction.

As I read the manual, the front of the board/copter is to the right in your photo the forward facing arrow being next to the blue switches on the board and pointing to the right. Therefore motor 1 is top right in the photo and should spin clockwise. That rotor is facing counter clockwise. I see rotor 2, bottom right in the photo, on your copter is facing clockwise. It should spin counter-clockwise. Swap rotors 1 and 2 and reverse the motors so they make the props blow air down. Do the same with rotors 3 and 4.
 

xuzme720

Dedicated foam bender
Mentor
If all 4 motors are reversed, would that create flipping? Seems like it would only effect yaw, like reversing it since the torque would be reversed. Since the board will compensate by throttle changes, I would think that it would still work in line with the thrust...
I might need to experiment with this some.
 

Craftydan

Hostage Taker of Quads
Staff member
Moderator
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I might need to experiment with this some.

Better your props than mine. ;)

Dunno about yaw miscorrection causing flipping, but it should rapidly amplify to a hard yaw almost instantly, which might make it tumble on the ground.

Not saying that's it, just saying that's not quite right.


Flitetester,

have you had a chance to give it a try again?