error running the

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Posts: 5
Joined: Wed Jan 31, 2018 6:54 am

error running the

Post by teihoshi » Fri Jun 08, 2018 3:15 am

hi crazyfliers,
we set up the LPS successfully and entered the coordinates in the anchor position tab and the crazyflie position appeard correct.
So we tried flying a cf by running the script.
We changed the coordinates set in the and ran the python script.
But it printed "could not save cache,no writable directory" and the cf just ramped for a little while without taking off.So I stopped running the code by pressing Ctrl+C.I wonder why this would happen. thanks for any comments!

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Joined: Tue Feb 06, 2007 12:36 pm

Re: error running the

Post by arnaud » Mon Jun 11, 2018 10:55 am

The two errors are unrelated.

The cache errors means that there is no cache folder set for the log and param TOC. A cache folders allows for faster connection but is not required for the lib to work. See ... /issues/68 for the issue where cache functionality where added to examples.

For the Crazyflie not taking off, what is the Z estimate? Since it started the motors it seems that the Z estimate is off and so the Crazyflie thought it was already over the setpoint so the first things I would check is that the Z part of the position estimate is correct.

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