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MAVLink to ROS gateway with proxy for Ground Control Station
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Optical Flow Message #511

Closed tuofeichen closed 8 years ago

tuofeichen commented 8 years ago

Hey guys, I was a little confused by this message: ~px4flow/raw/optical_flow_rad (mavros_msgs/OpticalFlowRad)

Specifically, is the integratedx the position estimate? or is it the still the velocity estimate? I ran the px4flow_node here http://wiki.ros.org/px4flow_node and it seems to yield reasonable result. However, when I tried to capture and plot the `~px4flow/raw/optical_flow_rad', I can't quite make sense out of the integreatedx and integratedy measurement either way (as position or as velocity).

Also, even though the topic name is quite self-explanatory, I just want to make sure this is the raw pose estimate from the flow sensor ONLY right? not fused with any IMU data or any other velocity/position sources.

Thanks for the clarification!

Best Francis

mhkabir commented 8 years ago

@tuofeichen IntegratedX is integrated (accumulated) optical flow rate around body X axis (similar to a gyroscope). And yes, this is raw data.

tuofeichen commented 8 years ago

Hi @mhkabir, Sorry so what's the unit of it? Is that a m/s or anything like that ? cuz my understanding is flow rate raw data is something like a pixel/s or something?

Thank you so much!

Best Francis

tuofeichen commented 8 years ago

oh wait I think I got it, this is the radian .... duhh... no wonder I'm confused.

Thanks!

mhkabir commented 8 years ago

Radians yes. See the i2c integral frame on the PX4Flow page.

pixhawk.org/modules/px4flow