Extricating Spirit, Digging out from Troy Options

[briv1016]

5 downsampled navcam frames from sol 2078 are down. Someone might want to make an animation.

[jamescanvin]

Sunspot,
My impression from the line:

"As the rover began its first move, it sensed that its roll was outside the allowed limit and safely stopped the drive."

Is that the roll of the vehicle was *already* out off allowable drive limits before even starting the drive. i.e there was a mismatch between the actual roll of the vehicle and what the drivers thought it was when setting the limits. As soon as the first roll limit check was made after the drive started, this was discovered and the drive stopped.

[fredk]

My impression... Is that the roll of the vehicle was *already* out off allowable drive limits before even starting the drive. i.e there was a mismatch between the actual roll of the vehicle and what the drivers thought it was when setting the limits.

My original interpretation was that the change in roll after starting the drive exceeded the limit. But this quote from the update supports your conclusion:

From this limited drive the team now has a more accurate measurement of vehicle roll and pitch that will be used for subsequent drive planning.

Still, answering Centsworth's question from above, there definitely was a roll during the short drive attempt. Compare hazcams from 2088 and 2079. In both front and rear cases, the horizon tilts between 2079 and 2088, which means there was a roll. The direction of roll that causes that change in horizon tilt is down on Spirit's left side/up on her right side. My guess would be down on the left rather/more than up on right. So that means she's sunk a bit deeper into Scamander on her left.

But from those same hazcams you can also estimate the angle of the roll. In both cameras, the horizon rises by about 1 pixel on Spirit's left side from 2079 to 2088. It's unclear exactly what to take as the long arm of the rotation, plus there are significant distortions in these hazcameras, but that gives roughly a roll angle of 0.05 to 0.1 degree. That agrees surprizingly well with Centsworth's estimate of the roll based on the drop in z above.

One last comment that no one's made yet, before I blow Emily's analysis-to-drive-duration ratio completely through the roof: I definitely see the drive stopping prematurely as good news. The images showed very depressing progress had the drive proceeded for the planned 5 metres. But very little progress in less than one second is just fine.