Bitcraze Forums

Happy new year!

I received the Crazyflie 2 a couple of weeks ago and finally found some time during winter holidays to play with it.

In the beginning I had some problems with it, besides that I had to learn how to fly it as it is very reactive and it was drifting quite alot. The next day I read the post regarding the new firmware, downloaded it and flashed it. Now strange things started:

• After having flashed to the new firmware (2014.12.0) the CF started full speed, touched the ceiling and then bounced underneath it. I cought it and turned it off.
• When I turned it on again, there where just two motors spinning (the short power-on spin). I checked the motors and propellers to be clean from dust and turned it on again. Now there where three motors spinning, but the one not spinning now was spinning before. I left the CF turned off and switched it on several times for the next couple of hours. The combination of motors that started to rotate at power-on nearly every time was different.
• Also the blue LEDs were not fully illuminated sometimes, and there was no radio communication possible.
• Even the battery voltage was ok (checked that with a multimeter), I decided to charge it. After a few minutes the CFs PCB became quite warm, I guess more than 40°C. I could smell "electronic smoke", so I disconnected the charging cable. The battery had a normal temparature as when charging.
• After leaving the CF unpowered for 24h most of the symptoms disappeared.
• Now, when I hold the CF and push throttle and, for example roll, it is not stuttering as it did before and should do because I keep it fixed with my hand.
• Flying the CF works sometimes, but then suddenly it starts to run into a random direction and my steering attempts have nearly not influence on it.

I clearly want to say that I did not change anything from the working setup of the first day, except the firmware update.

To me it looks if the ACC/GYRO is not soldered in a clean way, possibly there is a shortcut that also could be the reason for the smell.

Can you give me some hints what I could examine or should I return the CF for replacement?


Kind regards, Simon

Hi,

Happy new year!

The firmware update shouldn't change anything, but something seems to have happened. The heated PCB while charging is normal, especially around the charger (close to the uUSB connector).

A few quick questions:

• How did you flash the firmware update? Did you try to re-flash it again?
• Did you try to balance the propellers like in this guide
• Did you try disconnecting the battery?

/Marcus

Hi Marcus,

thank you for your reply.
I flashed it another time inbetween to make sure that there was no glitch during the flash process. The propellers were pretty balanced, possibly they are not anymore now as they show some scratches from the bounces at the ceiling.

The CF2 was totally disconnected from power (battery and USB) for at least 24h.

Nothing of this changed the issues.

kind regards, Simon

Were you able to figure out the issue?
I'm facing a similar problem.
My quad didnt crash though. It is behaving weird all of a sudden.

@codeman
There has been cases with badly soldered MPU9250 sensor. Please fill in this form and we will arrange a replacement board for you. If you have soldering skills and access to hot air station you could also try to reflow the MPU9250 as a quicker solution.

Thanks for the response tobias!
I'll fill up the form.

I've forwarded it to Seeed who will arrange a replacement board for you.