DESCRIPTION, DIAGRAMS AND EQUATIONS OF PARAMETRIC DESIGN

DESCRIPTION, DIAGRAMS AND EQUATIONS  

I could not be able to apply to apply this parametric design into the project because of the time limitation.  

In this project, there are 3 buildings with 6 different S-shaped roofs and because of limited time, I only modeled the building on the left on the original drawings. This building has also two different S-shaped roofs. These roofs are different from each other but share the same parameters. Parametric modeling is a very good tool to achieve that kind of complexity in design problems. Radius and of the arcs are changing from one roof to other. 

There are two problems: (A) roof and (B) columns which carry the roof.

(A)  Roof:

Each S-shaped roof consists of two arcs, and for each roof, the radius and length of these two arcs are changing. The heights of columns are consequently changing as well according to the radius and length of arcs which is discussed further in next section.

These are the steps that I followed in order to create this parametric model: 

(1)   Through generic model family template, in elevation view, I created an X-Y coordinate system and placed center of two arcs. I defined the coordinates of Arc1 as X1 and Y1, whereas Arc2 as X2 and Y2. One of the major problem that I came across was that I had some trouble to fix the center points (X1,Y1 and X2,Y2).  Then I realized that if I put reference planes according to X and Y coordinates and draw the circle through using the intersection of these planes, Revit automatically fix the center of circle/arc. 

(2)   After placing the circle reference lines as tangent to each other, I add parameter to radius of each arc: R1 as radius of circle on left and R2 as circle on right. However, the major problem in this level is how to constrain these two arcs in order to keep them tangent each other, no matter what their radius are. Then, I used Hypotenuse Theorem and made the radius and X1,X2,Y1 and Y2 dependent on each other.  

(3)   In order to give the thickness of the roof, I draw two circle reference lines through offsetting 80cm of Circle 1 and Circle 2 and add parameter two their radiuses as well: R1_Offset, and R2_Offset.

(4)   To be more flexible on the shape of the roofs, I define two angles for each arc and add parameters. This allows me to get a variety of roof structure.

(5)   Lengths of the arcs are also important and we need to know, in order to decide the shape of the roof. In other words, the length of the buildings and roofs are also changing in this project so we need to the length of arcs. To calculate the length of the arcs, I used the formula above.

(6)   Then, I flex it.

(B)  Column Height 
In the file Project1_Family2.rfa, I could not update the roof family. In other words, the drawings of roof ius not same as the parametric family above.

Since the roof has S shape, the height of columns which carry is changing. 

(1)   To define the base level of the building, I draw a reference line and add parameter to the height between base level and the peak of arcs.

 (2)   The locations of columns are determined according to the span of the columns and I draw reference planes from center of circles to the attached point of the column to arcs. This is important to determine the angle as seen in the diagram below.

ARC1

ARC2

 

(3)   This angle is used to calculate the distance between center of circle and intersection point of arc with column on Y axis. 

(4)   Then subtracting the distance between base level of building and center of circle from the distance calculate on previous step gives us the exact height of the column. 

  

My Experience:

This was my first time to model a project by using Autodesk Revit. Previously, I worked with different software such as AutoCAD, 3ds max and Photoshop in 2D drawings and 3D modeling involving plans, sections and elevations. While each of these programs was only capable of doing one task at a time, Revit is able to perform all these tasks in one package. For instance, during the previous process of drawing my current project, I used AutoCAD to draw plans, sections, elevations and after completing these 2D drawings, I proceeded with a rough 3D model of the building in AutoCAD and then transferred it to 3ds max to add materials and render it. After being finished with renders and 2d drawings, I exported them to Photoshop in order to color the drawings and prepare a layout for printing. 

In contrast to all this previous experience, Revit offers a chance to perform all these steps without having the need to use any other program. Based on my experience with Revit during modeling of this project, I found the software to be very user friendly. It provides an opportunity for users to compare and control both 2D and 3D drawings at the same time. This is what used to be missing before utilizing Revit. 

Revit also enables users to reflect all the changes that they make to apply to all the drawings.