Crazyflie 2 doesn't hover?

[erwincoumans]

This tiny crazyflie 2 quadcopter doesn't hover and is impossible to fly. Is there any way to enable stable hovering?

Note that my controller has no lag, so that is not the issue. The main issue is that the copter doesn't auto-hover.

[whoenig]

Most bigger quadrotors achieve that using optical-flow mechanisms. The Crazyflie 2.0 is not equipped with a sensor for that, so this is not possible in the moment. However, it might be possible with an expansion in the future...

[tobias]

We just wrote about unbalanced propellers on our blog, it seems that many of the CCW propellers are unbalanced and needs balancing. That is probably why it does not hover as it should. We have put together a guide on how to balance them, it is not that difficult and only takes a couple of minutes.

EDIT: Updated links, oops...

[chad]

Oops. The link Tobias provided goes to the admin page. Until he has a chance to fix that, here's the link to the guide on prop balancing...

[erwincoumans]

I'll try it soon and report back.

Happy holidays!

[biggles]

Hi, I too believe my CCW propellers are unbalanced and have still not managed after balancing them with scotch tape to maintain a stable hover. There may be other issues of course, not specific to the propellers. However, from a customer support perspective, I would expect the good folks at bitcraze to ship me 5 working CCW balanced propellers to correct the problem, workarounds notwithstanding, since with taxes / shipping / fedex custom duties to canada + led ring, i've spent close to $280 dollars canadian. Does that seem unreasonable in your estimation?

[chad]

Hi, I too believe my CCW propellers are unbalanced and have still not managed after balancing them with scotch tape to maintain a stable hover.

How unstable is your hover?

Just due to the size, the Crazyflie will always require minor manual pitch and roll corrections to keep it in one spot. It won't hold a perfectly steady position at hover like large quads can simply because a nano-quad of this size is more susceptible to minor changes in air current, temperature, and pressure - even indoors.

I own three Crazyflies. Two CF1.0s and one CF2.0. Even after doing a very crude "scotch-tape" balancing on my CCW props, my CF2.0 has a far more "stable" hover than my CF1.0s - and this is mainly due to the slightly increased size of the airframe, props, and motors on the CF2.0. Even with significant balancing work, you'll not get a totally stable hover out of a nano-quad...

Is it possible you're expecting more than a nano-quad can deliver?

[biggles]

I'm certainly haven't given up working on hover optimization and I do appreciate your nano quad caveats. I will certainly try to trim it as best i can, i'm still working on getting the VM up. i'm currently using the iOS / bluetooth combo and i'm not sure trim adjustments are available there. i'm running OS X, so still working on the getting the VM / CrazyRadio pieces going. A work in progress. Thanks for sharing your experience, I might call on you for some advice if / when I make further progress, should you be so kind. All the best.

[tobias]

Hi biggles,

We at Bitcraze totally share your frustration with the CCW propellers, it's been a big disappointment for us too. Suddenly many of the CCW propellers got too unbalanced to work right out of the box. We are working with Seeedstudio to try to find the cause and also to fix it but these things tend to be difficult to get to the bottom with. The plan is to ship new CCW propellers to all customers that have balancing problems, we first have to fix it though and that have proven to be quite difficult.

The up side is that often when the propellers are manually balanced the performance will be the best. When it is well balanced it will make little noise, that is a good way of telling how balanced the propellers are.

[biggles]

thank Tobias, i am sure you guys have worked extremely hard to get CF 2.0 launched and continually supported, i have not given up hope at all and your. thanks for the prop tips, we shall persevere. when they / you're ready, i would appreciate a set of slightly better balanced props if that works.