Drone falling on one side while taking off

i made a quadcopter using arduino and am quite new to it. when i 1st flew it it fell on one of the sides
i used:
1800kv golden bldc motor
30 amp esc
1045 propellers
arduino uno and mpu 6050
fsi6 transmitter and reciever

what i fell is that problem is in calibrating because when i callibrated the motors and the increase throtle at 1st they all appear to start at same time but when i increase the throttle really really slow then i observe that all motors are not starting at the same time and same speed . what could be the reason for that?

Are you even running a version of ArduPilot?

As far as I’m aware, ArduPilot never ran on that combination of hardware, but even if it did, support for it would’ve been dropped over a decade ago.

Depending on what firmware you have - if it’s a proper PID control system (like Ardupilot) then it expects flight and a static test produces unexpected results that cant be relied upon.

I think you are in the wrong forum. In any case those motors are not suited to multirotors.

And, I don’t think jDrones is still around. Any info about that?
Well OK.
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