M4 doesn't work

[tobias]

Try to find why it does not spin freely. Is there hair tangled around the motor axle? Is the propeller pressing down on the motor bearing? Or is the motor damaged in some other way maybe?

[jack86]

Hi Tobias.

With no power it not seems to have any problems with rotation on M1. Propeller is rotating freely like others. No, there is no any hair, propeller is OK and the motor looks fine without any damage.

[tobias]

Then we are down to a problem with the motor driver (mosfet) or some cracked/bad solder joint. Do you have a any tools so that you can measure the resistance of the motor and the connector? There might be a bad connection. If that is not the case then I would guess something is wrong with the mosfet. Does the mosfet get hot? It's the 3-legged chip just next to the round motor solder pad.

[jack86]

Yes, I have a multimeter. I will make a measurements, and report it.
I will check mosfet also...

BR, Jack

[jack86]

Hi Tobias,

I checked all solder joint, and they are fine.


The resistance of the motor -M1 on connector is appr. 2.3 ohms.
It looks, like that M1 has a problems with polarity it is twitching left and right and become very hot.
Should be a mosfet a bug?

Best regards

[tobias]

I see you have the Geetech Crazyflie copy and I don't know what components they use or how they test it. So I can't help out that much other then that it is probably the mosfet which is damaged.

[jack86]

This is a copy of Crazyflie?? Can't believe it... F** crap!
I think I will threw it away...

Thank you Tobias for your help and kindness.

Regards

[noazark]

Hey All,

My M1 on an official crazyflie rev.f board does not work. I've independently tested the motor, which is fine, and I'm getting the correct resistance from the signal path as tobias described. Is there anything else to check?

[tobias]

There is probably something wrong with your mosfet as well. You can try to manual turn it on by shorting between VCC and the gate of the mosfet. The red circles in the picture in this post. Do this while the Crazyflie is on and without propellers and be careful not to short to anything else.