Crazyflie does not fly properly

Post here to get support
whoenig
Expert
Posts: 395
Joined: Mon Oct 27, 2014 2:55 am

Re: Crazyflie does not fly properly

Post by whoenig »

The ROS topic for /cf2/log1 uses a generic topic and is not aware of which variable you are trying to inspect. The proper way of visualizing is:

Code: Select all

rqt_plot /cf2/log1/values[0]
The order in the array matches the order of your configuration.
santiagorg2401
Member
Posts: 46
Joined: Sun Sep 08, 2019 2:28 pm

Re: Crazyflie does not fly properly

Post by santiagorg2401 »

Hi, thank you, I can only go to the lab on monday, so I will try next week and post the graphs, another problem I saw is that when I placed the Cf near the origin (LPS Node 0) (say a distance of 20 cm or less), it totally lost the position estimator, for example, I place it 20 cm away of origin (inside the hull) and the state estimator shows a position of -30 cm (out of the hull).
santiagorg2401
Member
Posts: 46
Joined: Sun Sep 08, 2019 2:28 pm

Re: Crazyflie does not fly properly

Post by santiagorg2401 »

Hi,
I am sorry I did'nt upload the plot, I was resetting the flight space bigger as you recommended, now It is 2.89 by 2.89 by 2.0 meters [x,y,z], I couldn't add more length to Z because it was already 20cm away to the roof, here it is the plot of the state estimates x,y, and z in the video in this link https://drive.google.com/file/d/1DLzMMR ... sp=sharing.
santiagorg2401
Member
Posts: 46
Joined: Sun Sep 08, 2019 2:28 pm

Re: Crazyflie does not fly properly

Post by santiagorg2401 »

It gets really noisy near to anchor 0, as you may see in this video https://drive.google.com/file/d/1Mb97m0 ... sp=sharing, the CF is still in the coordinates [0.40, 0.30, 0.00]
The stability improves a bit when the CF is in [0.50 ,0.50, 0.00], but overall when the cf is in the near of anchor 0 and is on the floor, it is not very stable.
I have a doubt, the anchors's Z positions that are near the floor (15 cm away) are supposed to be 0.0 or 0.15? (in the anchor configuration in cfclient)
kristoffer
Bitcraze
Posts: 630
Joined: Tue Jun 30, 2015 7:47 am

Re: Crazyflie does not fly properly

Post by kristoffer »

I recently discovered that the antenna delay seems to be wrong (https://github.com/bitcraze/crazyflie-f ... issues/680) and this causes the distance measurements in TWR to have a negative offset of around 20-30 cm. Maybe this is what you are seeing?
santiagorg2401
Member
Posts: 46
Joined: Sun Sep 08, 2019 2:28 pm

Re: Crazyflie does not fly properly

Post by santiagorg2401 »

Hi,
I am using TDoA v2, I do not know if that same problem applies with it too.
kristoffer
Bitcraze
Posts: 630
Joined: Tue Jun 30, 2015 7:47 am

Re: Crazyflie does not fly properly

Post by kristoffer »

The antenna delay is cancelled out in TDoA and should not have any effect.
I don't know why you get noisy results, but you mention that it is worse close to the floor, maybe the floor is causing problems? If there is a lot of metal in the floor (rebar, sheet metal or similar) it might act as a mirror.
santiagorg2401
Member
Posts: 46
Joined: Sun Sep 08, 2019 2:28 pm

Re: Crazyflie does not fly properly

Post by santiagorg2401 »

No, the floor is ceramic and it has a plastic mat on top, this is a photo of the lab I took several days ago when I was extending the box [please check attachments], of course when working those boxes are not there, and it is at least 30 cm away from any metal structure, the white tubes you see are made of PVC, I do not have a newer picture but currently the mat is more organized, the cables are cut at a shorter length, and the box is centered so there is enough space from the sides.
Attachments
WhatsApp Image 2021-02-19 at 16.09.18.jpeg
kristoffer
Bitcraze
Posts: 630
Joined: Tue Jun 30, 2015 7:47 am

Re: Crazyflie does not fly properly

Post by kristoffer »

I'm not sure what advice I can offer.
Is the whiteboard metal?
Is it maybe the radio environment that is the problem? Have you tried to set up the system somewhere else to see if it works better?
santiagorg2401
Member
Posts: 46
Joined: Sun Sep 08, 2019 2:28 pm

Re: Crazyflie does not fly properly

Post by santiagorg2401 »

No, the whiteboard is made of wood and plastic.
Well, the lab is located in a basement (-2nd floor), but the space in the university is very limited, so we cannot test it somewhere else.
Post Reply