Some beginner questions?

[luckpolar]

Recently , I succeeded to control the crazyflie by leapmotion. And I have made some parameters changed in order to control it easily.
But, for the parameters of Crazyflie clients, I still have some parameters confusions.
What is the parameter "ASL" mean?(Maybe a wiki page is better than words.)
I identified a hand gesture to command the Crazyflie for hovering attitude,but the Crazyflie couldn't hover stably,in fact the crazyflie drifts(sometimes for a direction and sometimes for another direction) .
So,what should I do? I have adjusted the center of mass and it seems that I have to set the trim of pitch and roll before each flight.
I saw some algorithms in graphics which could assist the pilot and crazyflie for a more stable attitude, and I want to do a Wireless FPV system for my crazyflie.
So,what should I do first?
Are there any suggestion for my plan?
Looking foward to your replies.

Yixiong Xu

[whoenig]

ASL means Above-Sea-Level and is computed based on the barometer pressure. There are not many details available, one start would be here http://wiki.bitcraze.se/projects:crazyf ... itude_hold and the forum (there are some old posts about it because the mode was developed by a user).

Drift: Do you experience an issue with the height or is the height stable but the flie drifts in x- or y- direction? It is possible to set the trim values permanently (across restarts) using the bootloader: http://wiki.bitcraze.se/projects:crazyf ... bootloader. Those values should be fairly constant as long as you make sure that you start the Crazyflie on a level surface (it does auto-calibration in the beginning).

There are some forum posts about FPV systems for the crazyflie, you can use the search and see if they are applicable in your case.

[luckpolar]

ASL means Above-Sea-Level and is computed based on the barometer pressure. There are not many details available, one start would be here http://wiki.bitcraze.se/projects:crazyf ... itude_hold and the forum (there are some old posts about it because the mode was developed by a user).

Drift: Do you experience an issue with the height or is the height stable but the flie drifts in x- or y- direction? It is possible to set the trim values permanently (across restarts) using the bootloader: http://wiki.bitcraze.se/projects:crazyf ... bootloader. Those values should be fairly constant as long as you make sure that you start the Crazyflie on a level surface (it does auto-calibration in the beginning).

There are some forum posts about FPV systems for the crazyflie, you can use the search and see if they are applicable in your case.

Thanks a lot.
Working on the FPV!~