Can I customize estimator/controller in python for a crazyflie?

[jsuh9]

I would like to use my own custom controller/estimator and looking through the repository, I am not able to locate any scripts on Kalman Filter and PID controller (how they are implemented). Where can I locate these? And can I make modifications on those scripts?

[whoenig]

These are implemented directly on-board the firmware, see https://github.com/bitcraze/crazyflie-firmware/tree/master/src/modules/src. So unfortunately changing it in Python is not possible.