Closed dirksavage88 closed 9 months ago
This issue has been mentioned on Discussion Forum for PX4, Pixhawk, QGroundControl, MAVSDK, MAVLink. There might be relevant details there:
https://discuss.px4.io/t/holybro-optical-flow-sensor-thoneflow-oscillations-on-main/34768/1
As requested @dagar @bresch here are three logs that show an attempt at a box pattern as well as spinning by hand in position mode while armed (but landed):
1) box pattern: https://review.px4.io/plot_app?log=08d11193-1a40-498f-b366-cd56d09862eb 2) Spinning 1: https://review.px4.io/plot_app?log=9ed53bbc-df6c-41e1-95c2-882b4cd0bfda 3) Spinning 2: https://review.px4.io/plot_app?log=6ad9c489-5c97-4fcc-b172-a645d395fc93 4) EKF2 replay from box pattern: https://review.px4.io/plot_app?log=27ad9e20-8aa6-4d33-a137-3d20e8fe3348
Hello @dirksavage88 !
I observe exactly the same phenomenon with the same hardware (pmw3901, thoneflow driver in UART). My setup is Holybro's px4vision in v1.5. Note that I also have the Holybro PX4Vision in v1, with the PMW3901 in SPI, but with this configuration, I do not observe any oscillations. You can view the logs: v1.5 : https://review.px4.io/plot_app?log=d2530b83-3116-4b63-a292-8a3d440a3993 v1 : https://review.px4.io/plot_app?log=e8908b3a-7745-41a9-859f-4bbdddd4349a
Looks like the scale in the driver might be wrong. Try divide those scales by 2 (replace 3.52e-3 by 1.76e-3): https://github.com/PX4/PX4-Autopilot/blob/8aab3e80133e9f31b5826198309ba1c1d224302e/src/drivers/optical_flow/thoneflow/thoneflow_parser.cpp#L136-L137
This patch has greatly improved OF performance with this sensor for me:
Before, note the oscillations with no RC input:
After, lack of earlier oscillations:
Thanks @bresch!
Describe the bug
I've tested the holybro uart sensor on a 210mm wheelbase quad and found severe position oscillations when using 1.14, main, and even going back to 1.13.3 stable. I swapped the holybro sensor for the Ark can flow sensor with updated cannode firmware (recent main) that includes the gyro bias estimation fixes. The ark flow worked great.
See this forum discussion: https://discuss.px4.io/t/holybro-optical-flow-sensor-thoneflow-oscillations-on-main/34768
To Reproduce
Enable the thoneflow driver, set the OF, EKF2, and rangefinder params, and take off in position mode
Expected behavior
Optical flow position mode holds stable position with minimal oscillation
Screenshot / Media
Here is a pitch angle plot from the holybro sensor:
Same exact hardware setup except the ark flow:
Flight Log
Holybro (like a merry go round) : https://review.px4.io/plot_app?log=94031e37-9350-4b03-a76e-19fdd9cdcf4d Ark can flow (I'm not moving): https://review.px4.io/plot_app?log=7ea5d915-144a-45ff-971c-76aa3d33732e
Software Version
tested with similar results on stable, 1.14 beta, recent main
Flight controller
holybro 6c mini
Vehicle type
None
How are the different components wired up (including port information)
No response
Additional context
No response