Using a basestation facing upwards, and the crazyflie upside down.

[knmcguire]

Discussed in https://github.com/orgs/bitcraze/discussions/1518

^{Originally posted by cafeciaojoe August 16, 2024}
Hello all!

I have conducted a basic test to see how stable the lighthouse system is when the are three basestations, with one of the base stations facing upwards. The test involves roughly estimating the variance of the "stablilizer.roll" and the "stateEstimateZ.z" variables whilst the crazyflie is mounted on a tripod facing up (about 0deg roll), sideways (about -90deg roll), and upside down ( about -135deg roll).

The system was calibrated using the wizard, in the latest version of the client and using the latest firmware on a cf 2.1. The third basestation was not visible for the first three steps of the wizard (ie origin, origin + 1m and n number of XY plane measurements)

I encountered some major variance during this experiment when the crazyflie was using the basestation facing up.

There was some insane "oscillating variance" (9deg roll and 200mm height), that was fixed with a restart of the crazyflie, but then some significant and slightly more random variance after the restart (not in the roll, but 50mm in the .z)

if you scrub thru this video you can see how I collected the data. Let me know how I can improve this experiment and provide better data for our diagnosis

https://youtu.be/GtufDYDOZto

Thanks all !
Joe