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Creating an Assembly Offset
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I've just been looking at the Assemlby Offset but not sure what it is useful for - please can someone enlighten me???
(No connection with Autodesk other than using the products in the real world)

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Re: Creating an Assembly Offset
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With assembly offset and ETW target
With normal assembly, same target.
The offset needs its own alignemtn AND profile. As you can see, you are not limited to your corridor sections being perpendicular to the baseline alignment, instead they are perpendicular to the target alignment.
Cansel - Autodesk Division
http://www.cansel.ca/
Re: Creating an Assembly Offset
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Very nice pictures, thanks for creating those. What happens in the small gaps at the beginning and end of the offset region when you make a corridor FG surface?
C3D 2012
Re: Creating an Assembly Offset
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I'm not sure why I don't have more sections near those gaps, but any surface would just triangulate across those areas. There's a chance you'd have to swap a few edges to make the TIN correct.
Cansel - Autodesk Division
http://www.cansel.ca/
Re: Creating an Assembly Offset
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Thanks for this - I've never really looked at assembly offsets before as never had any need...![]()
(No connection with Autodesk other than using the products in the real world)

IDSP Premium 2014 (mainly Civil 3D 2014 but also 3ds Max Design)
Win 7 Pro x64, 256Gb SSD, 300Gb 15,000 rpm HDD
16Gb Ram Intel Xeon CPU E5-1607 0 @ 3.00GHz (4 CPUs), ~3.0GHz
NVIDIA Quadro 4000, Dual 27" Monitor, Dell T3600
Re: Creating an Assembly Offset
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I don't know if this has been fixed in 12 or 13 but in 11 you are not able to extract a feature line from an offset assembly and maintain dynamic connection to the corridor.
Snip from my SR:
Thank you for your update. That is part of the issue. You seem to be creating feature lines (links) with the offset assembly. The issue is that program is not able to create the feature line. I hope this will be fixed in the near future. Unfortunately I have no information when.
Joseph D. Bouza, P.E. (one of 'THOSE' People) Civil 3D 2012 & 2013
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Note: Its all Resistentialism, so keep calm and carry on

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Re: Creating an Assembly Offset
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Please program Civil 3D to have the capability to recognize that the subassemblies that are outside of a transitioning alignment have to be oriented perpendicular to that transitioning alignment for correct surface triangulation.
Users now have to go through the extra work to set up an Offset Assembly, come up with a clever Profile scenario, (or a MarkedPoint configuration) just to realize proper triangulation that should be occurring in the first place.
Then the user has to keep the above mentioned extra Corridor, Assembly, Profile or MarkedPoint, overhead in mind for the duration of the project. This type of non-elegant overhead unnecessarily detracts from the good aspects of Civil 3D.
Super elevation axis of rotation is not supported with Offset Asemblies. Therefore, how does one get proper triangulation outside of the LaneSuperelevationAOR subassembly with superelevation?
Thanks
Fred
Fred Ernst, PE
C3D 2013 SP1, C3D 2014
W7x64; i7 8gb; Radeon HD 5700
www.ernstengineering.com
Re: Creating an Assembly Offset
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These are probably due to the offset value between the channel line and the widening offset alignment being too small or zero, I get this a lot.
Instead of assembly offsets insert a different subassembly or you could use a conditional "Target found" subassembly in this region as I do.
If you then allow the two regions to overwrite each other by a small ammount or until they are perpendicular to the master alignment then you can erase the underlying subassemblies and you will have the gaps filled and ready for setting out (NB: a carefully positioned second conditional target found would also do this instead of edits).
Obviously you still need to provide a profile for the offset alignment but the outside edges will be correct.

