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Moderators: Barry Kelly, Karl Ottenstein, LaszloNagy, ejrolon, gkmethy

By nimai2
has anyone ever created a custom curved ramp in the history of archicad?? it would be the achievement of the century if i could do it just once for an important project i'm working on.

i know archicad has a curved ramp tool but it only lets you follow a circular path not a custom one.

of course you can create a custom curved path as i have done using spline and then slab or mesh tool but this is not a ramp until one end is higher than the other.

I basically want this ramp to go from say 0 - 6 metres high at a uniform gradient.

i have tried objective (much of my hair was pulled out trying to get it to do what i wanted) but my conclusion is that the 'regular profile' does not, will not and never has any intention of following a 'defined' path you give it... only the path that regular profile wants to follow.

i could raise every randomly spaced mesh point individually calculating how high to raise each point each time... this would take 78,000 light years and i have only 2 days to figure it out.

any help is greatly greatly appreciated!!

custom curved ramp.jpg
User avatar
By adzik
You can do it with Mesh and SEO. Here's how:

1. Create polylines that mark the contour of the ramp. Duplicate them and then create two separate meshes. The first part should end a little before the ramp crosses itself for the second time so you wouldn't get any errors about intersections etc.

2. Magic wand the two meshes inside the contours. This makes sure that you have a minimal number of points on the mesh.

3. Offset one of the polylines to create a centerline for the ramp.

4. Open the Element Information panel (Window/Palettes/Element Information).

5. Select the centerline and note its length from the EI panel.

6. Split the centerline into separate parts (Explode into current view) and then starting from either end of the ramp select one part of the exploded polyline and check its length from the EI panel. With a few simple math equations (think percentages) you should be able to get the needed amount of elevation for that specific point on the mesh.

7. Elevate the meshpoints according to your calculations. Rinse and repeat.

8. When done Elevate a copy of the meshes downward as much as needed and then SEO the meshes separately and place the operators on a hidden layer.

9. Voila!

Hope this helps
Last edited by adzik on Mon Aug 30, 2010 1:42 pm, edited 1 time in total.
User avatar
By Matthew Lohden
If you use the mesh tool with equal spacing of the contours you can then increment the elevations falrly easily. What you are running into, partly, is the inherent difficulty of what you are attempting.

Keep in mind that it is impossible to maintain equal slope over any curved ramp as the inside and outside slopes will vary. This can be quite extreme on tight ones. Imagine the inside and outside handrails of a spiral (helix) stair. Where the outside rail could rise 7" in a 16" run the inside rail will have to rise the same amount in a fraction of the distance. The inner handrails in some old castle stairs I've seen get quite close to vertical.
User avatar
By Dwight
All that i can add is to suggest defining the ramp using a sinuous wall with the multi-segment wall tool and pet palette. This will provide the optimum number of control nodes to trace the overhead meshes.