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crazyflies are not stable

Posted: Mon Nov 05, 2018 6:08 pm
by azamali
I am using flow deck for simple hovering from ubuntu 18.04 terminal. Crazyflie is not hovering at a particular place as I expected. I I have tried from VBox earlier. Result is more or less the same. Crazyflie is going to left side (slightly) and waving vertically. I have 3 crazyflies, and all of them are behaving same way.
In my code I tried thrust (32767) for a few seconds. Please help me with possible reason for this and the right way I need to try.
For your information: I have tried multicolored surface, white surface, etc. Result is better when I used multicolored surface, but still shaking.
Please share a link where I can get a python code for hovering a crazyflie. Thank you!
Please also help me with how do I make sure my flow deck is working properly.

Re: crazyflies are not stable

Posted: Tue Nov 06, 2018 7:42 am
by arnaud
Hi, can you maybe share a short video of the behaviour you are observing?

There can be small shaking in Z but X-Y should be very stable if the tracking surface is good. Depending of the version of the flow deck you have you should limit Z: Flow deck should be used bellow 1m and Flow deck V2 can be used much higher depending of the floor surface, 2 meters works fine on wood floor.

The two example you can try are the flow sync sequence that fly a figure 8: ... and the motionCommander example that flies a small sequence: ...

Re: crazyflies are not stable

Posted: Tue Nov 06, 2018 11:39 pm
by azamali
Thank you!
Crazyflie is basically shaking in Z axis but I was expecting something smooth hovering. Please see the video from my drive: ... sp=sharing. I have used code from bottom of this link: viewtopic.php?t=2167. The guy said crazyflie stays about 15 cm above.

So, do you think I need to change ground surface? or any other issues like interference or propellers?

Please be informed that I am not using LPS right now. So, I can not run flow sync sequence or small sequence. All I wanted to make it hover. And please let me know whether LPS is mandatory with flow deck or not.

Re: crazyflies are not stable

Posted: Thu Nov 08, 2018 8:14 am
by arnaud
This is too much shacking indeed, at most you should get some millimeters. It seems like you are not using the flow functionality at all. Have you tried any of the example I sent the link to?

For reference, the following script addapted from ...

Code: Select all

import time

import cflib.crtp
from cflib.crazyflie.syncCrazyflie import SyncCrazyflie
from cflib.positioning.motion_commander import MotionCommander

URI = 'radio://0/96/2M'

if __name__ == '__main__':

    with SyncCrazyflie(URI) as scf:
        with MotionCommander(scf) as mc:


Gives me this result:

Re: crazyflies are not stable

Posted: Thu Nov 08, 2018 5:29 pm
by azamali
Thank you again! Problem is solved now. I needed to update crazyflie-firmware. :) I totally unaware that crazyflie firmware is for CF1.

Re: crazyflies are not stable

Posted: Fri Nov 09, 2018 6:58 am
by arnaud
Crazyflie firmware is for CF2 (it does not support CF1 anymore) and yes, one of the first thing to do when you assemble your Crazylfie is to update the firmware :). Great that the problem is solved!