Logging variables

[jess5906]

Hello,

I am VERY, VERY new to Crazyflie and all things associated (Python, GitHub, etc...), so I have a very basic understanding of how things work if you'll keep that in mind as you're assisting me! I've gotten familiar with the cfclient and want to move onto using Python to log data and eventually control the Crazyflie autonomously. To start with logging data, I am following this tutorial and am on Step 2a: https://www.bitcraze.io/documentation/repository/crazyflie-lib-python/master/user-guides/sbs_connect_log_param/

In addition to the stabilizer variable, I wanted to add the kalman_pred and motion variables to be able to track the drone's motion. When running my code, the kalman_pred variable is not able to read anything and I get values of 0 for my x and y positions, even though I'm moving the drone. And for the motion variable, my code isn't able to run at all and I get a key error. I will provide a picture for each case to better explain my issue.

Any assistance would be greatly appreciated!

[ArisMorgens]

Hello jess!

Getting started with the Crazyflie's autonomous flight is really amazing! You might face some challenges, but don't hesitate to reach out if you have any questions!
Regarding your issue, the new variables you added in your script demand a Flow deck attached to your Crazyflie. Do you have one attached when running the scripts?

[jess5906]

Thank you! Controlling the crazyflie autonomously is a very distant goal I have set for myself, but luckily I am busying myself with logging variables first (which is already becoming a handful).

Yes, I do have a flow deck attached and it was reading properly while I was using the cfclient to control the drone.

[jess5906]

Actually, now that I'm looking closely at it, it seems that the cfclient only detects the Multiranger deck on the crazyflie and not the Flow v2 deck:

DECK_CORE: 1 deck(s) found
DECK_CORE: Calling INIT on driver bcMultiranger for deck 0
...
DECK_CORE: Deck 0 test [OK].

Unfortunately, I was not the one to assemble the crazyflies, so I'm not sure where the issue could be.

[jess5906]

Sorry for the multiple replies! I just wanted to update and say that I retrieved a crazyflie that has a functional multiranger and flow deck, and am now using that since I want to just focus on the code for now. After switching, the code is able to run and output the kalman_pred variable!

Are you aware of any other tutorials for logging variables that may assist me in further developing the code? For example, in the code above, I want to display the stabilizer, kalman_pred, and motion variables, but I am only getting the kalman_pred variable. I am also not sure if the outputted values are accurate, but at least it worked!

[ArisMorgens]

Hello again!

So nice to hear that you managed to output the desired variable!
After you finish the first tutorial, you can move to the step-by-step motion commander tutorial. There, on Step 4 you can better understand how to properly log a variable while flying.
Adding more variables will be clearer then. You can create different LogConfigs just like you already did and then call them to start() in __main__.
I hope this helped. Don't hesitate to ask any questions.