[trikkky]

First Quad build.

Im trying to get it to hover in one spot before i can start testing PID's or even learn to fly.
Ive tried trimming from the remote and from libre, but i cant get it to stay still.
The quads COG (Centre of grav) is in the middle where the flight controller is.

anyone know any tutorials(ive seen a few) or guides i can use?

[Brian]

There will always be some drift if you don't have GPS, and even then it will drift within the uncertainty of the GPS position.  Getting a quad to hover in one spot is actually not easy, especially if your PIDs are not tuned well.

Can you post a quick video so we can see if the drift is unusual?

[Brian]

Getting a quad to hover in one spot is actually easy, especially if your PIDs are not tuned well.

Rephrase? 

actually NOT easy! 😃

[Mateusz]

Can you post a quick video so we can see if the drift is unusual?

Yes please short movie. Some drift is normal, but if the drift is so bad that you can't control the vehicle than I would check

• PIDs way off (are these default PIDs?)
• Unbalanced propellers or FC mounted loosely or other sort of serious vibrations

Maybe someone else has some ideas. I remember I couldn't control my first 450mm quad when FC was mounted too lose because of vibrations, after installing it on plastic standoffs it flew perfect.
By the way, you should never use any trims on your transmitter.

[TheOtherCliff]

By the way, you should never use any trims on your transmitter.

^^^ That is important.

And the way that you do trim to correct drift (in beginner / Attitude / Stabilized1 mode) is with Attitude -> Settings -> RotateVirtual.  Don't fret with making it perfectly built since there are manufacturing tolerances that you can't account for.  It simply must be aligned with RotateVirtual.

RotateVirtual is like aligning the wheels on an automobile.  It is something that needs to be done to every vehicle, and redone after there is crash repair or if it drifts.
 - if it is drifting forward you subtract from pitch
 - if it is drifting left you subtract from roll
try subtracting (even to below zero) or adding to these to make it drift less.  Start with say 3 degree increments and try to get it as perfect as 1/2 degree or better.  Of course it will drift if there is wind (and not using GPS) so this should be done with no wind and then land, rotate the quad 180 degrees, walk to the other side of it (so it is facing forward where you are now standing) take off and see if it drifts when pointing 180 different direction (this adjusts for even a small wind that you can't really feel).

[trikkky]

its been really windy here for the past few days so i didn't want to risk flying. Will upload a video as soon as i can.
All your tips sound great. will definitely try them

[trikkky]

Ok so i got a chance to fly it in minimal wind today and I was amazed at how controllable it was. I guess i wasn't manually compensating enough for the drift earlier. But I will still try out all the suggestions provided to further improve the performance.
however, i noticed if i keep it at a certain altitude with the throttle at lets say 50%. After a few seconds of being stable, it starts to drop unless i increase the throttle.
Is this the Kp that needs to be tuned?
I have attached a dropbox link to a video as well.
https://www.dropbox.com/s/b7ka3s22xiptz88/Video%202017-05-15%2C%208%2007%2024%20PM.mov?dl=0

[TheOtherCliff]

Without GPS / baro stabilization it is like driving a car.  If you take your hands off the wheel, you will wind up in the ditch sooner or later.  If you leave your foot at the exact same place on the accelerator pedal, you will either run into the car that is ahead of you or you will open up a larger and larger gap.  You must constantly correct.

When it is well trimmed, there are only tiny corrections that need to be made.