Bitcraze Forums

Hi all, Please see the video below of our crazyflie (tracked by lps) hovering at a fixed point in space. Our final goal is to have four drones flying in a tight space (1,5 x 1,5 x 1,5m). For this we need a very accurate setup. Does anyone have experience with multiple drones in a tight space? And are there any tips & tricks to increase the accuracy of LPS?

Video: https://www.youtube.com/watch?v=n53zySC ... e=youtu.be

Hi,

X/Y looks quite OK but the Z accuracy is quite bad. We have seen that reducing vibration can increase a lot the Z accuracy, you can try to balance your propeller and if you had crash before maybe some motor are vibrating a bit much.

The current position controller is not ideal and there has been work on new feed-forward controllers that should land in the master branch (hopefully) soon.

Hi, We just discovered and fixed a bug that should improve the LPS performance: viewtopic.php?f=17&t=2279, this should help with the stability.

Thanks Arnaud, we'll check this out. I'll also fly again with a new copter because the one you saw in the video crashed a number of times.

Hey bart,

Nice work. I was wondering if you had the chance to test the drone after the fixed bug that arnaud mentioned.

Good luck.

Sorry for the delay. Yes we have updated the firmware of the Crazyflie. It does indeed perform better. Especially on the Z axis. But we're not sure yet if it's a good idea to let 4 quadcopters fly together in a tight space.
https://www.youtube.com/watch?v=uYpqou_ ... e=youtu.be

Are you using TDoA or two way ranging? It still looks quite shaky, I think we are getting better hover stability than that. 4 CFs in a tight space might indeed be challenging.