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All 4 passenger masses were turned on.
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Learning Note
Had difficulty setting up the solids (gussets and sheet metal) which caused solver pivot errors.
Learned that solids need to intersect the beam elements or be very close so that the bonded contacts work properly and solve.
An approximate fix for the back bar case could be to move the collision object close enough so that it intersects the C plane and solve.
Front Bar
Back Bar (Failed to Compile)
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