Logged values units

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meToo
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Joined: Tue Aug 12, 2014 2:39 am

Logged values units

Post by meToo »

Hi everyone,

I am posting this here because I couldn't find an answer anywhere (except "look into the code", which didn't exactly help...).
I was wondering what were the units for the values logged by the quad, more specifically for the accelerometer, magnetometer and gyro.

For example, I get "1.06" as a raw value for the accelerometer on Z axis, but that doesn't correspond to the gravity acceleration in any unit I can think of.
So I guess this is not the standard "m/s^2", and for the rest of my code I'd also like to know what kind of units you use for magnetic field and gyro.

Thanks in advance!
arnaud
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Re: Logged values units

Post by arnaud »

Hi,
Indeed I had to look in the code. It would actually be interesting to store that in the copter table of content so that it is transmitted to the ground automatically. I added a ticket for it.
The accelerometer unit is g, the mean acceleration gravity (g=9.81m/s^2).
The gyroscope in degree per second.
The Magnetometer in gauss.

Best regards,
meToo
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Re: Logged values units

Post by meToo »

Hi arnaud,

Thanks for the prompt reply, great!
I'm using a bunch of your quads for my master thesis. Your help is greatly appreciated ;)

Regards
arnaud
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Re: Logged values units

Post by arnaud »

Hi,
No problem. Do not hesitate to share more about your thesis, we are always interested to hear how Crazyflie is used.

BR,
Arnaud
meToo
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Re: Logged values units

Post by meToo »

I am using the CrazyFlie to do some sound processing (which is not easy because of the ego noise of the copter).

The principle is to use sound landmarks to self-localize each quad, then use this swarm of quads to localize an unknown sound source. You can find a short document about the principles here:
http://www.jp.honda-ri.com/upload/docum ... 7_7070.pdf

I am doing a short presentation at a robotics conference soon, and I was wondering if it was OK to use pictures of the quad from your website? They are so much more beautiful than the one I took :/
arnaud
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Re: Logged values units

Post by arnaud »

Sounds really cool!
Of course you are welcome to use our photo.
meToo
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Re: Logged values units

Post by meToo »

Thanks a lot!
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