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Bad readings when using two basestations

Posted: Thu Feb 04, 2021 12:55 pm
by gustafaman
I am having trouble using two basestations (v2). Depending on which basestation is used I get vastly different results.
When I am plotting lighthouse.angle0x the values change between +-0.025, and when plotting lighthouse.angle0y, the values change between -0.25 and -0.65.
If I cover/block one of the basestations the plots are smooth and reasonable but as soon as I let the other basestation take over the readings shift in an instant.

I followed all the steps of the setup process with calibration data and geometry data , but somewhere it must have gone wrong.

Re: Bad readings when using two basestations

Posted: Fri Feb 05, 2021 9:28 am
by kristoffer
Hi!

Have you configured the base stations to use channels (modes) 1 and 2? This part was unfortunately missing in the instructions but was added recently. You can find the instructions here https://github.com/bitcraze/crazyflie-f ... hthouse-v2

The other thing to check is that your calibration data is correct. You'll find instructions in the same page of how to extract it from the base stations.

Re: Bad readings when using two basestations

Posted: Fri Feb 05, 2021 1:44 pm
by gustafaman
Thank you. I had not set the channels and that seem to have solved the problem of the switching values.

Re: Bad readings when using two basestations

Posted: Fri Feb 05, 2021 2:25 pm
by gustafaman
Not sure if this falls under the same issue, but I will post it here anyways.
I now get lighthouse.angle0x and lighthouse.angle0y values that reads smoothly.
However, the values does not fully correspond to the XYZ-frame based on the CFs origin, my thinking about this is that the read lighthouse.angle0x values correspond to the basestation reference frame.

Next, as soon as I manually lift the CF into the air (without covering the Lighthouse deck) the state estimates starts jumping around. This I have no idea about and would appreciate some help.

Re: Bad readings when using two basestations

Posted: Mon Feb 08, 2021 12:47 pm
by kristoffer
It sounds like your geometry data may be wrong, have you set it according to the instructions?

We are currently adding lighthouse configuration functionality to the client, and even-though we're not done yet, we have implemented a visualization of the system. If you update the firmware, python lib and the python client to the latest versions from github, you will find that there is a lighthouse tab with a 3D system view. It might help you to understand if the geometry data looks OK.

Re: Bad readings when using two basestations

Posted: Mon Feb 08, 2021 2:20 pm
by gustafaman
Now it works! I thought that I had done the geometry part, but apparently not correctly.
Perhaps it could also have been that previously when I got the geometry data I had placed the CF in the wrong direction?

Anyways, thank you for the help!