Flow deck issue

Discussions about autonomous flight in general, regardless of positioning method
Unibasudent
Beginner
Posts: 4
Joined: Wed Sep 05, 2018 2:06 pm

Flow deck issue

Post by Unibasudent » Thu Sep 20, 2018 8:41 am

Hi Crazyflie team, i'm trying to perform a swarm using 5 Crazyflie with flow deck ad the code in cflib "swarmSequenceCircle". The drones take off, but after a while each of them goes in a random direction, there seems to be problems with the drone imu and the flow deck, how can i calibrate the imu and the flow deck?

Thanks in advance



tobias
Bitcraze
Posts: 1916
Joined: Mon Jan 28, 2013 7:17 pm
Location: Sweden

Re: Flow deck issue

Post by tobias » Fri Sep 21, 2018 8:13 am

Hi!

Can you be a bit more precise in the description, e.g. when do they take of in random direction? Did you place the CF2 in the direction of the "ASCII" art as drawn in the swarmSequenceCircle file.

If you fly only one with e.g. flowfigure8 how does it fly then? I'm thinking maybe the tracking surface is not feature rich enough or possible shadows casted under the CF2 fools the flow sensor.

Unibasudent
Beginner
Posts: 4
Joined: Wed Sep 05, 2018 2:06 pm

Re: Flow deck issue

Post by Unibasudent » Fri Sep 21, 2018 9:14 am

Hello, and thanks for the answer.

I placed the Crazyflie as illustrated in the script, I did new tests and I noticed that: in the flowfigure8, the drone follows the path quite well, but in some places tends to destabilize, as if it losing power, in Crazyflie's client I also noticed that when it is stopped on a flat surface, the imu is not stable, it keeps moving with small tremolos. is there a way to calibrate the imu? or even the flow deck?

Thank you.

tobias
Bitcraze
Posts: 1916
Joined: Mon Jan 28, 2013 7:17 pm
Location: Sweden

Re: Flow deck issue

Post by tobias » Mon Sep 24, 2018 12:10 pm

If we could see a video it would be easier to know what is happen. From your descriptions it sounds like there sometimes is not enough features on the ground or that shadows is fooling the flow deck.

The "unstable" IMU when landed is because of noise from the flow deck and that is normal.

The performance of the flow deck could probably be improved a lot as there are many corner cases that are not handled now, like what should happen when flow tracking is lost...

faria
Beginner
Posts: 12
Joined: Mon Jun 17, 2019 4:30 pm

Re: Flow deck issue

Post by faria » Wed Nov 27, 2019 4:38 pm

Hello,

Any update about this problem?
I have the same problem. Any suggestions?

arnaud
Bitcraze
Posts: 2212
Joined: Tue Feb 06, 2007 12:36 pm

Re: Flow deck issue

Post by arnaud » Thu Nov 28, 2019 8:55 am

@faria Can you please describe the problem you are getting with the flow deck?

faria
Beginner
Posts: 12
Joined: Mon Jun 17, 2019 4:30 pm

Re: Flow deck issue

Post by faria » Fri Nov 29, 2019 2:52 pm

Thanks Arnaud.

System:
Crayflie 2.0 and 2.1
V2 Flow Deck
Loco Position

Problem: When I´m using the flow deck I have lot of noise in pitch and roll and yaw (height stable). Without the flow deck, only with loco position I dont have noise.

video
https://drive.google.com/file/d/14IvHa2 ... Jo9gS/view

faria
Beginner
Posts: 12
Joined: Mon Jun 17, 2019 4:30 pm

Re: Flow deck issue

Post by faria » Mon Dec 02, 2019 1:13 pm

With Flow and Loco i have this noise on the figure "withFlowandLoco.png"

Without Flow and with Loco i have less noise on figure "withoutFlow.png"
Attachments
withoutFlow.png
withFlowandLoco.png

arnaud
Bitcraze
Posts: 2212
Joined: Tue Feb 06, 2007 12:36 pm

Re: Flow deck issue

Post by arnaud » Mon Dec 02, 2019 3:21 pm

Hi,

This looks like noise from the LPS itself. Do you only have the noise on the ground or also after take-off? The flow should mostly be used by the estimator when the Crazyflie is flying.

faria
Beginner
Posts: 12
Joined: Mon Jun 17, 2019 4:30 pm

Re: Flow deck issue

Post by faria » Mon Dec 02, 2019 3:36 pm

Thanks Arnaud.

In ground I have noise. When i am flying sometimes the drone have 'crazy' movements and after crash. I realized several tests in different places (external noise) but i have the same results.

Tests *5:
Flying with LPS and FlowDeck, with the same drone and the same mission. Takeoff, waiting 5 minutes, and land. On five tests, 2 i have problems (crash) and 3 perfect flight.

Post Reply