Tying Feature Lines to Corridor

[Anonymous]

Here is the deal. I have to grade the infield, turfed area, between a proposed airport taxiway and an existing runway. The taxiway is being designed by others and we have to match into it. I have taken the other designer's data and created a corridor. So far, so good. At various spots I drew feature lines that go from a feature line representing the existing edge of the existing runway to the dynamic taxiway, snapping to the top layer of the corridor. I have additional feature lines snapped to the first set of feature lines. 

I want to create a surface bounded by the runway and the taxiway. Since I can't control the taxiway design, I have to adapt my infield design to it. So if the other firm comes back and tells me the taxiway has been moved, I want all of my feature lines to move when I update the corridor.

Since I do not know how to add a corridor to a surface, I created a dynamically linked feature line along the edge of the taxiway where I have to tie in. As a test to see which objects would react to which, I changed the profile of the corridor after having done all of this. The feature lines I drew from the existing runway edge to the corridor by snapping to it remain totally unchanged. The dynamically linked to the corridor feature line stayed with the revised corridor, but sent a bunch of spikes down to the unchanged fetaure lines I drew sanpped to the corridor.

I want this to all update automatically - the corridor controls, the feture lines that are tied to the corridor should follow it, and the feature lines that are tied to those feature lines should follow them after they've followed the corridor.

Any tips on how to achieve this?

thanks.

[Anonymous]

Exactly, John. You can't trust the paste to do it. Steve may have the right idea, but I would have to think alot harder than I am at the moment to really interpret his post. (I'm working in 2D today) BUT - the end result, as you correctly note, has to be one surface. Not a bunch or corridors and grading objects and feature lines in separate surfaces. And if you paste just be aware that that is how the dozers are going to build it. I will usually do the transitions between different surfaces "by hand." I seriously don't know why you can't add a GO or corridor to a surface def, but there it is.

Attached is the 3d drawing containg faces for the airport improvements I modeled. I had to cut it down to size to get it to be small enough to upload - the taxiway at the top extends for some distance both easy and west in real life. There is a bakground file containing all the lineweork you want the operator to see provided, too. They can set the machine to follow a pavement edge or something like that that makes sense when they grade it.

[Anonymous]

Oops, it took both drawings. identical, except one has greater extents.

[sboon]

What - you can't understand my Canadian accent ??

If you have a grading group - which can automatically have a surface, then any feature lines or grading objects you create will become part of that surface.  If you extract featurelines from a corridor then they would be automatically added also.

I'm not sure but I think that you can also paste a corridor surface into a grading group surface, assuming that your corridor is daylighting properly so it has a clean connection.

[jmayo-EE]

'I'm not sure but I think that you can also paste a corridor surface into a grading group surface, assuming that your corridor is daylighting properly so it has a clean connection."

Yes  you can Steve. Any TIN surface will paste to another TIN surface. It doesn't matter if it's a corridor, FL or grading surface.

The clean connection you mentioned is my main point. IMO the paste operation was not design to grade for us and should not be considered an option for any grading transition. So I won't trust it because it shouldn't be used. There must be an x,y,z common line of intersection for any paste operation.

[Anonymous]

No, I could undertsnad you OK, eh? I just couldn't digest everything that you were saying, because I have never used a garding site, so am unsure of how it works. But, it sounds like it should work. and then you either have a common line between corridor surfaces like John suggests, or add the corridor components as feature lines once you are assured that it likely not going to be cahnged any further. 

I think what you are talking about is when the feature lines and GO's interact with each other, right? Soo you pul a FL line up here, and the GO recomputed and the other FL may update if  they are attached? What I don't know how to control, but what would be essential, is which FL or GO's control, and which are allowed to update. I have also notticed, I think, that if you add vertices to a FL to get a smotther surface then it won't update all of those vertices - it only moves the one that is attached to another grading feature - right? And this is obviously unnacceptable. 

There is a way to do this where you get the stuff good for producing plan sheets only - maybe 60% of what the GPS usable model looks like. And obviously, you'd want to wait to do the final model until after thee design is set. Problem is the contractor wnats to start the day after tomorrow, and the designer may still be tweaking things.

So that is ultimately what I am after and why I asked my originall question. I want to be able to take an entire site as close to finished as possible, but still have it as dynamic as possible so that I have the least possible rework, or possibility of a bust because I overlooked something, as possible in the event of a change to the design.

[Joe-Bouza]

You know that pasted surfaces are dynamic, right?

[Anonymous]

Perhaps a different suggestion - we do a lot of airfield work as well, so your runway safety areas / grades should be well defined and limited to what grades you can use for the infield area.  I'm guessing your limits of work are the other firms taxiway safety area, as I wouldn't want to be responsible for grading someone else's TSA - the object free area is a different liability, but regardless, you have some definitive point of connection that is potentially dynamic.  If you build a Taxiway corridor for their proposed TSA area to their limits of work - you don't need to get too fancy - you can use one of the generic stock subassemblies - you can then create a surface from your taxiway corridor - you can also then extract/create a feature line from the corridor - which will be dynamic to the taxiway corridor should it change.  You can then use this feature line as a target for your runway corridor which you create.  So you have 2 corridors, one being the more complex one you are responsible for - the other being a simple one that you can change if you need too...  

So your limits of your runway corridor needs a subassembly that has the ability to contain both an OFFSET target and ELEVATION target - you then tell the corridor to target the taxiway corridor feature line created above.  If that taxiway corridor changes horizontally and/or vertically, your runway corridor will dynamically update as it targets the feature line from the taxiway corridor.  Frankly, I doubt you will have any offset changes as the FAA geometries are pretty set, but profiles can certainly change but this shouldn't be much of an issue since your ELEVATION targets are tied to the feature line which is tied to the corridor.  

If you have the Subassembly Composer - watch the two Autodesk University videos by Katie and Peter by searching "Subassembly Composer" under the Online Classes tab on the AU website.  It took me a weekend to get it, but I experimeted by creating a custom subassembly for a group II taxiway all the way out to the OFA limits...  The ability to create custom subassemblies with OFFSET and ELEVATION targets is excellent, and much easier to "follow" for me, than using the stock subassemblies and searching through the help file to figure out which link code applies to which link, etc.  The perpendicular feature lines you are talking about drawing are set by your sampling interval in your Runway corridor - so build your runway surface from the RW corridor (there is a tab in the corridor properties) and use the links and feature lines as "breaklines" and your surface will be done.  If you watch those videos, you'll see the links run perpendicular and the feature lines connect the points along the profile - so you get feature lines running both directions which results in very good triangulation for the TIN.  If you create a custom subassmbly, you will need point codes in order to make feature lines between them for your surface.  If it sounds confusing, it is at first but gets very simple very quickly once you see it work.      

[Anonymous]

Thanks for the great reply!

My situation is slightly different than what you describe. We are for the infield area between the taxiway (by others) and the existing runway. We are putting in a glide slope antenna, so have to make sure the critical area is good, and account for drainage at the same time. But, I think with your ideas in addition to other ideas found in this thread, I am farther down the line to creating a dynamic situation. Actually, because of the FAA constraints, not much is likely to change on the taxiway. So this has been as much of an exercise in learning to become an expert as it was for this particular project.

thanks again.

and Joe - I know surfaces pasted from corridors are dynamic, but pasted surfaces are unnaceptable as explained in previous posts.