PX4Flow position estimation

Hi, is there a log parameter to view the position/path of the drone, which is estimated by integrating the optical flow velocities?


you have to enable optical flow (OF) logging. Once you do that you will start seeing a parameters in the logs that displays your OF position info and other info.

Hi, thanks for the reply! I have OF logging enabled and I am only getting those messages:

As far as I know, flowX and flowY are the velocities in X and Y direction and bodyX and bodyY are the angular velocities around the X and Y axis (please correct me if I’m wrong). Are there more parameters that can be logged, such as position info?

Optical flow doesn’t give you position information, that’s calculated from the velocities by the EKF.

Hi @OXINARF, thanks for clearing that up!

From what I understood from the EKF documentation, the NED position that is calculated by the EKF are the NKF1.PN, NKF1.PE and NKF1.PD messages. How are those calculated? Only using GPS or also with optical flow?

I’m not an EKF expert, but position is calculated by fusing all available data: GPS, optical flow, IMU.

Thanks @OXINARF, that’s what I needed to know!