Geodesic Dome Construction in Autocad

[mher]

Attached files is from Dome supplier, just finding hard to do it in my own. a lisp maybe of help much appreciated. Thank you!

cadtutor.dwg

[fuccaro]

Constructing a dome can be pretty complicated. I am not a "dome master", in the far past I wrote some Lisps for the Icosahedron based domes - just to help someone in this forum and for my own pleasure. In the drawing you uploaded I can see some "discontinuities", going from the center outward, the orientation of the triangles changes two times. Probable it should be so, as I told, I am just amateur in this field. Or maybe the dome was produced by slicing a solid sphere and automatically extracting the surface, letting the software to use it's own tessellation algorithm?

So, what do you need? To reconstruct the dome you uploaded? Or a lisp for a dome? If so, what kind of dome? Icosahedron based? What frequency?

 

[lrm]

I'm not sure what constitutes the difference between any dome and a "geodesic" dome but the dome you have from a "Dome supplier" is not a geodesic dome. One way to visualize a geodesic cuve is to imagine a wheel rolling along a curve on a 3D surface. If the wheel can roll without twisting it's a geodesic curve.  In this sense, longitude lines and the equator are geodesic curves but othe latitude lines are not.  I believe a geodesic dome is one derived from an icosahedron as noted in  Buckminster Fuller's original pattent.  It may  have different levels of frequency (how many members are used to connect from one icosohedron vertex to the next vertex) but at these vertices there will be  five struts. Your dome shows a mishmash of shapes abd six struts at the dome's apex. 

 

As @fuccaro asks,  what do you need?  I'd start with constructing an icosahedron.  A true geodesic dome will use only 3 different  strut lengths.   

[marko_ribar]

Here is routine I modified long time ago and it produces all 3 types of geodesic spheres : tetra, octa, icosa... When geodesic sphere is created, just go to front view and remove bottom faces to get dome out from sphere...

Link : https://www.cadtutor.net/forum/topic/34841-how-to-build-4v-geodesic-dome-in-autocad-2012/?do=findComment&comment=518099

 

HTH.

M.R.

[marko_ribar]

And here is the topic where I used different 3 point or 4 point 3d faces to create various interpolated polyhedral spheres... I hope you'll find this topic very useful for presentational purposes... And one more thing - you have spheres *.ZIP in download section here at cadtutor also for free...

 

https://www.cadtutor.net/forum/topic/38335-geodesic-dome/

 

https://www.cadtutor.net/forum/topic/38335-geodesic-dome/page/2/#comment-322075

 

https://www.cadtutor.net/forum/files/file/41-spheres/

 

HTH.

M.R.

 

[marko_ribar]

I've just watched your *.dwg... Lower curves of dome are Vivijan's curves and upper ones are continual lattices that references Vivijan's curves... So this is not geodesic dome at all... For geodesic domes refer on my firstly posted link... But why would you do that when there are dozen's of examples what can be printed on domes - spheres...

[mher]

Thank you for the reply, i don't know dif. types dome construction but this is how they called it the industry "Aluminum Geodesic Dome Roof"  used for large storage tank. maybe some other dome manufacturer called it different. & Thank you marko_ribar  for the free *.ZIP in download section.