Flight Controller: Snapdragon Flight
Using guide https://github.com/PX4/snap_cam to set up optical_flow.
I have compiled the optical flow app from the snap_cam repository following the instructions in the link above. I then try to run ./optical_flow -n 50 -f 30 from the appropriate directory. However, I get generally the following output:
[ INFO] Using VGA/cameraParameters.yaml for calibration [/home/linaro/programs/snap_cam/src/optical_flow.cpp:122] [ INFO] local port: 14558 [/home/linaro/programs/snap_cam/src/optical_flow.cpp:193] [ INFO] remote address: 127.0.0.1:14557 [/home/linaro/programs/snap_cam/src/optical_flow.cpp:200] Number of good matches: 1, desired: 50 Number of good matches: 1, desired: 50 [ WARN] No valid measurements [/home/linaro/programs/snap_cam/src/optical_flow.cpp:496] Number of good matches: 1, desired: 50 [ WARN] No valid measurements [/home/linaro/programs/snap_cam/src/optical_flow.cpp:496] Number of good matches: 1, desired: 49 [ WARN] No valid measurements [/home/linaro/programs/snap_cam/src/optical_flow.cpp:496] Number of good matches: 1, desired: 49 Number of good matches: 1, desired: 49 [ WARN] No valid measurements [/home/linaro/programs/snap_cam/src/optical_flow.cpp:496] Number of good matches: 1, desired: 50 [ WARN] No valid measurements [/home/linaro/programs/snap_cam/src/optical_flow.cpp:496] Number of good matches: 1, desired: 50 [ WARN] No valid measurements [/home/linaro/programs/snap_cam/src/optical_flow.cpp:496] Number of good matches: 1, desired: 50 [ WARN] No valid measurements [/home/linaro/programs/snap_cam/src/optical_flow.cpp:496] Number of good matches: 1, desired: 50 [ WARN] No valid measurements [/home/linaro/programs/snap_cam/src/optical_flow.cpp:496] Number of good matches: 1, desired: 50 [ WARN] No valid measurements [/home/linaro/programs/snap_cam/src/optical_flow.cpp:496] Number of good matches: 1, desired: 50 [ WARN] No valid measurements [/home/linaro/programs/snap_cam/src/optical_flow.cpp:496] Number of good matches: 1, desired: 50 [ WARN] No valid measurements [/home/linaro/programs/snap_cam/src/optical_flow.cpp:496] Number of good matches: 1, desired: 50 [ WARN] No valid measurements [/home/linaro/programs/snap_cam/src/optical_flow.cpp:496] Number of good matches: 1, desired: 49 Number of good matches: 1, desired: 50 [ WARN] No valid measurements [/home/linaro/programs/snap_cam/src/optical_flow.cpp:496] Number of good matches: 1, desired: 50 [ WARN] No valid measurements [/home/linaro/programs/snap_cam/src/optical_flow.cpp:496] Number of good matches: 1, desired: 50 [ WARN] No valid measurements [/home/linaro/programs/snap_cam/src/optical_flow.cpp:496] Number of good matches: 1, desired: 50 [ WARN] No valid measurements [/home/linaro/programs/snap_cam/src/optical_flow.cpp:496] Number of good matches: 1, desired: 50 [ WARN] No valid measurements [/home/linaro/programs/snap_cam/src/optical_flow.cpp:496] Number of good matches: 1, desired: 50 [ WARN] No valid measurements [/home/linaro/programs/snap_cam/src/optical_flow.cpp:496] Number of good matches: 1, desired: 50 [ WARN] No valid measurements [/home/linaro/programs/snap_cam/src/optical_flow.cpp:496] Number of good matches: 1, desired: 50 [ WARN] No valid measurements [/home/linaro/programs/snap_cam/src/optical_flow.cpp:496] Number of good matches: 2, desired: 49 Number of good matches: 1, desired: 48 [ERROR] IMU buffer is empty while catching up [/home/linaro/programs/snap_cam/src/optical_flow.cpp:336] [ERROR] IMU buffer is empty while catching up [/home/linaro/programs/snap_cam/src/optical_flow.cpp:336] [ERROR] IMU buffer is empty while catching up [/home/linaro/programs/snap_cam/src/optical_flow.cpp:336] [ERROR] IMU buffer is empty while catching up [/home/linaro/programs/snap_cam/src/optical_flow.cpp:336] [ERROR] IMU buffer is empty while catching up [/home/linaro/programs/snap_cam/src/optical_flow.cpp:336]
This output is followed by pretty much only the [ERROR] statements indefinitely. I have added the lines
mavlink start -u 14557 -r 1000000 -t 127.0.0.1 -o 14558 mavlink stream -u 14557 -s HIGHRES_IMU -r 250
to my /usr/share/data/adsp/px4.config file at the end, so I believe that the correct mavlink messages should be passed from px4 to optical_flow. I have looked into the code at the snap_cam repository (link at top) that generate the [ERROR] message, and it seems that either the IMU is not working or the optical_flow application is not receiving the correct mavlink messages.
PX4 may be indicating the issue here as well, but I haven’t been able to quite figure out what is wrong yet. Occasionally, on starting px4 with ./px4 mainapp.config from the /home/linaro directory I will receive the messages:
ERROR [muorb] Error: Getting Bulk data from fastRPC link ERROR [platforms__posix__px4_layer] update_value_from_shmem get param failed
Possibly the first error, dealing with muorb messages, is the reason for my troubles here. I don’t know if my notion of what is happening is correct, but muorb sends messages via RPC across the apps and adsp processors, right? Thus, if the muorb fastRPC link is generating errors, perhaps the IMU data is not being received.
At any rate, I hope that there is an easy fix/alternative, and if anyone can figure out what is wrong, a workaround, or wants more information, let me know.
Edit: px4 is built from eagle_legacy_default. i.e. px4 with FC_ADDON drivers.