Bitcraze Forums

Hello, everyone, right now I am trying to build a close-loop controller for the crazyflie v2.1. I use a optitrack motion capture to provide pose feedback of the crazyflie. My first plan is to put four markers on the crazyflie(here is the video link:https://www.youtube.com/watch?v=u-Kh69y7k9I), and under this case, the markers are too close, which will introduce noise to the pose information of crazyflie, but the flight is stable. In order to improve the tracking precision, I printed a marker frame(from here:https://github.com/peteflorence/crazyflie-CAD) and I put 4 markers on this frame and then integrated it with crazyflie, but under this case, the crazyflie will crush every time at the startup step(here is the video:https://www.youtube.com/watch?v=eJK74EXXWA0). The closed-loop position controller is the PID controller and the position command is sent by a host computer. My initial guess is that the marker frame will change the center of gravity, but then I tried different ways to put the markers on the frame, all of them are failed.

Is anyone faced the same issue and can share some ideas here?

It is hard to tell why it crashes but it looks like it is stuck on the carpet during take off. Other thing might be if you switched a propeller to the wrong type, then the crash often looks like that.