Vizard expects vehicle coordinate system origin to be aligned with center-of-mass. Offsetting spacecraft models causes dynamics to be improperly displayed.

[JT-247]

Describe the bug
It seems like Vizard expects the spacecraft coordinate system to always be aligned with the center of mass of the vehicle. The center of rotation in Vizard is always about the coordinate system origin, when it should be the center of mass of the vehicle. If the coordinate system is offset from the CM, then the spacecraft appears to rotate about the coordinate system origin.

Translating .obj models to align the coordinate system origin in Vizard with the center of mass will fix the issue for rigid body spacecraft, however if flexible panels are modeled (using spinningBodyNDOFStateEffector), then the hinge point will appear outside the panel body (hinge point does not move with translated obj).

To reproduce
Steps to reproduce the behavior:
I've included an tweaked test case for the scenarioFlexiblePanel where the center of mass of the vehicle is offset from the coordinate system origin. The .obj files are offset so that the center of mass is co-aligned with Vizard's center of rotation / displayed coordinate system origin. If you run the test case and visualize in Vizard, you can see that the flexible panels are attached to the hub at the correct location (after oscillation settles), however the hinge points are not correct.

scenarioFlexiblePanel_CM_not_aligned_with_CS.py

1. Run attached test case
2. Load results in Vizard
3. Go to view->Show spacecraft CS in Vizard
4. Observe center of motion is co-aligned centered about center of mass, however panel hinge points are out in space

Expected behavior
Vizard should animate center of rotation about aggregate center of mass of the vehicle, not coordinate system origin.

Desktop (please complete the following information):

• OS: Ubuntu Linux
• Basilisk v2.8.0