Complex Drilling Scenario
by Buck Wyckoff on Dec 22, 2010 at 11:28:25 pm
I have a complex drillstring with a bottom hole assembly (drillbit plus stuff on top) and drill pipe segments above. This is drilling with a liner, so there is a liner (larger pipe surrounding the inner drillstring) which rotates in unison with the drillstring, however at some point the inner and outer strings come apart (with components within each string moving a little, slips and dogs popping in/out etc). I used a path deform object space modifier (probably should have used world space path deform), and launched down the hole. And the path bends because this will show deviation during the drilling process.
So the whole thing rotates, the inner string drillbit rotates faster and then these arms are supposed to come out. The only thing I tested was whether I could get the entire assembly to go down the path and rotate cleanly (no wobble) around the bend. It did.
Now the whole thing blew up in my face when I tried to make the arms come out. It seems all my object's transform gizmos do not stay with the object. They appear to be back where the object was when I first applied the modifier. If I bring the gizmo back to the object, that's no good as the arm does not rotate out, it gyrates all over the place.
Apparently, whne you path deform something, you cannot animate elements within the group while maintaining the overall path deformations. Why the gizmos don't come along for the ride is a mystery to me. A warning in the help would be nice...caveats to that modifier....hey, if you path deform a group of objects, don't expect to sub-animate things within the group.
Anyway, anybody got an idea where I should go with this? Yes, I'm up against a deadline.