Quadcopter beginner here - need help regarding stabilization

LasseRL

Junior Member
Hey there!
I've just completed my Q450 quadcopter build with 25A SimonK Escs, SunnySky 920kv motors and a KK2.1 flight controller.
When trying to obtain a hover, the thing just falls over. I think i've might found the error, but don't know which component is the faulty one. When i hold the copter in my hand and give it minimum throttle (without props ofc.) and tilting one motor down at a time, the lowest one should spin more than the other motors. 3 out of 4 motors does this correctly but the 4th motor simply maintain the throttle-speed without trying to compensate for the tilt. The wierd thing is, that if i hold the copter level and twist it around its own axis, like giving rudder, the motor that refuse to stabilize, now wants to stabilize.... All the sensors should be okay according to the kk2.1.
Does anyone have experienced something similar, or just have any knowledge about quadcopter stabilization? I really need some help here. :(

Have a nice day!
 

cranialrectosis

Faster than a speeding face plant!
Mentor
I think you are describing instaflip, where the copter never gets off the ground, it just flips over when you give it throttle.

If so, start by re-tracing your ESC connections to the KK2. The most common cause of instaflip is connecting the ESCs to the KK2 in the wrong order. Make sure the ESC for motor1 is connected to M1 on the KK2 and check them all.
 

cranialrectosis

Faster than a speeding face plant!
Mentor
Most of my bullet nuts have swirlies from running the copter upside down on the concrete. It's just freaking maddning. :D

Glad we could help.

Welcome to FliteTest!