mavlink stream -d ${MAVLINK_COMPANION_DEVICE} -s HIGHRES_IMU -r 200 in /etc/init.d/rcS (plug sd card to computer) edit px4/Firmware/src/modules/mavlink_main.cpp (ATTITUDE_QUATERNION parameter = 200) then edit camera_trigger_params.c in px4/Firmware/src/drivers/camera_trigger
1.GPIO trigger mode
2.TRIG_INTERVAL: 50.0 ms (20 FPS)
3.TRIG_POLARITY: 0 (active low)
4.TRIG\_ACT\_TIME: 0.5 ms
5.TRIG_MODE: 1
6.TRIG_PINS: 56
enable triggering through mavcmd in launch file modify point grey driver finally modify covariance and noise parameters in rovio info file