Modern Design from Historical Perspective
Around the globe many experts, scientists, and engineers have researched ways to preserve historic art, including architecture, for the future.
While we are grateful for the experts who recognized the historical significance of their works and published books, we recognize that there are those who didn’t transfer their wealth of knowledge and experience to others before they died.
We can surely design modern buildings, but without the knowledge of culture and history, we’re missing something.
With new technology we are able to create documents for every type of building. Using software such as Autodesk Inventor® Professional, we can renovate and build new structures while preserving culture and history.
In this article I describe how we can save this art and create documents of it with Inventor Professional.
Figure 1: Sepah Sallar
Inspiration for doors, windows, niches, and more come from a variety of sources. For example, view Figures 2 and 3.
Figure 2: Karbandi and Kaseh Bandi
Figure 3: Entering and arch 5 O 7
While Inventor Professional is essentially designed for the mechanical engineer, its abilities make it one of the best tools in the world for this type of design.
We use 2D and 3D sketching, part Modeling, multibody modeling, adaptive modeling, assembly design, frame generator, IPN presentation, documentation, iLogic, and many other features for this project.
Outline of the New Features
- Quick look at Karbandi
- Preparation of skeleton part
- Generative shape design
- Design connection part
- Documentation and benefit
Quick Look at Karbandi
Figure 4: Arch and niche
We have many type of arc combinations for creating arches for opening areas in the walls for any type of entrance.
In Figure 5 you can see an important type of arch, 5 O 7.
Figure 5: Prototype modeling for 5 O 7 arch
The base plan for domes comes from polygons, with a modular circular pattern around the Z axis of the polygon and a combination between arches. We create the dome shape; the name for this type of dome is Karbandi.
Figure 6: Karbandi in Mosque Ghazvin
Construction of this type of dome was dependent on workers’ skills. Often they did not have precise documentation and, in fact, they were doing this job based on experience. The whole structure was built in the site area and most of the time they couldn’t create good connections between the parts of the structure. Also, they are using a welding connection between the beam parts, and if you check some of structures in the site area you can find many faults in the connection point.
Figure 7: Current connection in the project
In many cases, the dome is shearing by itself and in other cases the dome has two separate parts: structure of the dome and the shell over the structure.
We can use Autodesk Inventor in both cases.
After structure preparation the area between beams should fill with masonry material and with this method we have a shell over the structure.
The final step could be tile or masonry material. In most situations, workers try to fill the area between the structure with a modular pattern of brick. This could be finishing layer for Karbandi.
Preparation of Skeleton Part
Introduction of Sketch for Arch
In Figure 8, you can see we have an arch for the opening in the wall. This shape name is 5 O 7.
Figure 8: 5 O 7 is sort of a shear arch
Each arch has a width for the opening area and in the half of width we have a vertical mirror line.
Each side is a combination of two arcs. The first arc is 45 degrees and the center point distance for this arc is (Length*1/6). The second arc is tangent; the first and center point of this arc should align vertically with the width of the arch.
You can use this arch for a door, window, and entry opening. Also you can use this shape for Mudolar pattern.
Figure 9: Shabdari Arch
Introduction of Dome for Karbandi
Review Figure 10 below and pay attention to the parts you can see.
Figure 10: Skeleton part
For the first step, we have a base polygon (green color) in the ground X,Y plane. Next is about a parameter with two X variables ( X*X ), with the first X an integer number and second X an angle of one segment for the polygon.
For the line that comes from X*X, we can create a rectangle (red color). The segments of this rectangle give us the orientation for arches that should be patterned around the Z axis of polygon.
A 2D sketch that contains arches should start from the start point at which segment is the length of X*X rectangle and the end of the arch should be in the end of length segment (black color).
Then if we have a polygon with 12 segments, we should have 12 arches around the sides of polygon.
Note: Inventor does not have the ability to create patterns from 2D sketches, so I prefer to create simple extrude, like a surface, and then create patterns from the extrudes.
After introduction with Arch and Dome, you need to know more about dome structure parts. You can see the name for each part of the interior body in the dome.
As described earlier, the area between arches should be filled with tile or bricks or some sort of masonry material. In Figures 11 and 12 below, you can see the name of each part for the dome and how we separated dome parts in Karbandi.
Figure 11: Shell of Karbandi structure
Figure 12: Legend
Generative Shape Design
Now we need the skeleton part and then we can bring the skeleton part in the assembly environment and save our file. We are able to use the generative shape design environment.
After placing the skeleton part and saving, you need to create many structural beams, shown in Figure 13. In real-world construction, this structure is built with square or angle profile shapes.
Figure 13: Skeleton with beams
I use a circular shape for many reasons. First, the shape of the circle in a section of beam can be very helpful for designing connection parts. Other issues can be solved with a circular shape; for example, where two beams intersect at the same point.
The tools available in Frame Generator make it simple to create and manage what we need for the Karbandi structure.
Figure 14: Final Frame Generator
Design Connection Part
Now for the most important part of the job. We did not have any type of connection part for Karbandi until now.
The theory for this part is a combination of some rules:
- Simple procedure for fabrication
- Minimum machining work
- A simple method for fabricating one connection part
- Similar and simple modular cut
- Ability for a simple assembly in the structure
- Using pitch and nuts for the structure assembly
The whole dimension and shape of the connection parts are coming from the location: what is the connection part length and what is the plan of Karbandi?
Figure 15: Connection part
iLogic option is very useful for this part. I wrote some rules between parameters for managing the whole connection part.
For entering correct values in the iLogic dialog, we need to take some information from the skeleton part. Inventor is very handy for this kind of thing.
Figure 16: Relation with connection part (red color)
We also need to prepare a guide surface for future beam trimming and modeling in the assembly environment. For example, we need a guide surface for trimming beam parts in assembly.
Figure 17: Beam trimming according to the guide surface
Documentation and Benefit
The final result is documentation and bills of material (BOM). According to the procedure of modeling that we used, it can be very simple to create precise BOM, cut lists, etc.
Figure 18: Document and BOM table
One of the most important things about this procedure is the preservation of art and knowledge. We can use this type of model for teaching in universities and other schools.
Because of the modular design for connection and the new procedure for fabrication, we can build this structure in the facility and assemble them on the site.
It is a very fast workflow to build this type of structure.
- BOM list for material
- Nesting list for pipe
- Decrease the fault in fabrication workflow
- Decrease overwork
- Decrease cost
- Create precise documents and guide parts for bending pipe according to what is needed in the structure
- Create base exemplar for connection parts
- Ability to renovate buildings corrupted as a result of earthquakes or war
Behzad Meskini is a BIM manager, BIM trainer, 3D modeler, and 3D modeling software trainer. He has more than 19 years of experience with 3D modeling software and is a Certified Professional in 3ds Max, AutoCAD, Inventor Pro, and Revit Architecture, Structure, and MEP. Behzad volunteers as a beta tester and was a speaker at Autodesk University ASEAN 2016.