Flow breakout - mesurement to cm

Discussions related to positioning systems where the position is calculated outside the Crazyflie and sent to the device using radio, including MoCap systems
Post Reply
Edouard
Beginner
Posts: 1
Joined: Thu Jan 24, 2019 9:13 am

Flow breakout - mesurement to cm

Post by Edouard »

Hello,

For my project, i want to use the flow breakout to mesure a deplacement.
For using properly the data, i want to convert them into cm.
I tried to understand the Marcus Greiff's Master Thesis but it's too complicated for me.

Can you help me ?

Thanks by advance
Edouard
arnaud
Bitcraze
Posts: 2538
Joined: Tue Feb 06, 2007 12:36 pm

Re: Flow breakout - mesurement to cm

Post by arnaud »

Hi,

If you want to see an implementation example you can look in the Crazyflie firmware. The Crazyflie is running a kalman filter and the flow update function is there: https://github.com/bitcraze/crazyflie-f ... an.c#L1062. The EKF code seems to be doing the oposite (convert velocity in pixel) and includes the platform rotation. Though from it is should be possible to get the formula to pass from pixels to cm and to remove rotations from the equations.
Post Reply