Here’s a first attempt to explore the I2’s instability whilst hovering. Any help, or (polite) suggestions, would be very welcome!!
My plan is to try to tie the problem down by exploring the parameters available to view in the DAT files which are recorded during each flight. There is a huge amount of information in the DAT files ranging from motor speed to ESC temperatures, RC movements to GPS data, and lots more which I don’t pretend to understand.
I've recorded video of the I2 whilst hovering (with no control inputs and in light winds), and provided sync points so that the data from the DAT file can be set against it.
When viewing the video the I2s behaviour will be correlated with the events shown by the timeline marker on the DAT data. The sync points between the video and the DAT data are the two yaw inputs (rotating the I2 through 180 degrees), which can be viewed on the video and seen on the DAT file timeline, along with other parameters of interest.
To get the ball rolling here is a first video - The craft was set up about 4m agl, beyond ground effect, with a camera trained on it. The I2 was set to record also. The I2 was rotated 180 by yaw input – this is represented by the blue trace on the screen, the falling edge of which is used as the start sync point. The rising edge of the second yaw input is the second sync. The video images are aligned with this data, so that the movement of the craft should be fairly closely associated with the other events chosen for illustration from the DAT file. I have picked Number of GPS sats (red) and Number of Glonass Sats (green). The steps show the loss or addition of a satellite - Glonass 10 -12, and GPS 11-12. The timeline indicator runs between the sync points. So the events on the graph should be occurring in sync with the video and the timeline indicator for the DAT view.
I don't see any definite correllation between I2 movements and GPS signal changes, but I do see the I2 video moving around as the craft sways about! Not what you want to see really!
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