Project to surface problem: adding an elevated road to terrain file

[rolfusTJQJW]

Hi. I'm new to Fusion 360 and I'm currently stumped by the following:

I have a .STL terrain mesh from google, and I'm trying to project some roads onto it. I want the roads to poke out / be elevated slightly from the ground. I've tried to make a sketch and use the line tool to make the roads, but I can't project them onto the terrain properly. In the image you can see my attempt, which resulted in... well... 

I want the road to follow the surfaces at some specified offset. Is this possible?

[jhackney1972]

Probably you will need to convert the Mesh into a Solid before you can do what you desire.  Attach your model so the Forum users can take a look.  If you do not know how to attach your Fusion 360 model follow these easy steps. Open the model in Fusion 360, select the File menu, then Export and save as a F3D or F3Z file to your hard drive. Then use the Attachments section, of a forum post, to attach it.

[rolfusTJQJW]

Thanks for the reply! Here's the .f3d file attached- 

I did convert the mesh into a solid, and tried following along with a few videos but none of them showed projecting to multiple surfaces like I'm trying to do. 

[jhackney1972]

Not having a lot of luck.  My idea was to see if I could offset the terrain surface and use it with the surface projection of your path to create a Boundary Fill.  I cannot get an offset surface as it is too faceted.  Sorry, gave it a try.

[rolfusTJQJW]

Thanks for giving it a try! I'm thinking that Fusion might not be the right tool for this, but I'm hesitant to try and learn something like Blender just for this one thing.

[davebYYPCU]

Not a lot of details in the file, or requested outcome, 

Like this as a starting point?

Your conversions choked Fusion, so reverted back to mesh body.

Might help.....

[rolfusTJQJW]

Hey, that's pretty good! The road seems to be at a pretty consistent height above the surfaces, which is exactly what I wanted. How did you do it? Is there a fast way to get your result for a much larger number of roads that'll be running in various directions across the map?

[davebYYPCU]

Well that depends on your definition of fast, how close to the terrain, and within what tolerances for smoothness.

This one was done as Tspline.  

You would need the street layout, as centre line.  Tspline Pipe, about average height, and then adjust the height, as required.

Might help.....

[laughingcreek · Accepted solution]

attached is a round about way of doing it with fusion. Your assessment that fusion isn't the right tool for this is correct. it's not great at working with meshes.
step thru the time line to see what I did.

I think @davebYYPCU approach is probably more appropriate here. a real road doesn't follow terrain exactly, but smooths out the elevation transitions and stays level across the width.

[rolfusTJQJW]

I'll look into T-Splines, but for the purposes of this project your solution worked a treat! Roundabout or not, the result is pretty much exactly what I needed. Thank you both for helping me out with this, it's greatly appreciated!