ARCH655 - Parametric Modeling in Design_ Project 1_ 2015 Spring

ARCH 655 - Parametric Modeling in Design

Project 1_ 2015 Spring

Texas A&M University

Instructor: Dr. Wei Yan

Introduction

Previously, a BIM-based parametric model of the Al Bahar Towers was developed by using Dynamo, a visual programming environment for parametric modeling in Revit. In this project, a parametric model of the Towers are also developed by utilizing Grasshopper, a visual programming environment for Rhinoceros developed by Robert McNeel & Associates. First, the proposed Grasshopper nodes describe the development of parametric relationship for floor plan, structure, and active shading devices like previous project.

Project Background 

The Al Bahar Towers, designed by Adeas, was constructed in 2011. Figure 1 shows the floor plan of the building.

<Fig.1 Floor plan of  Al Bahar Towers>

Parametric Modeling

Floor Plan

Parametric relationship of the floor plan are made up of regular tringles and circles. Figure 2 is Grasshopper nodes for floor plan, and Figure 3-7 represents how the edge of floor plan can be drawn.

<Fig. 2 GH node for floor plan>







<Fig.3 Floor plan process 1>



<Fig.4 Floor plan process 2>



<Fig.5 Floor plan process 3>



<Fig.6 Floor plan process 4>

Mass Model

Various sizes and Z values make multiple curves of floor plan in order to follow original design of the building, then, the mass is created by using “loft” node in Grasshopper (Figure 7 and 9). Based on the mass model, “contour” node serves as creating different sizes of slabs which can be manipulated automatically (Figure 9).

<Fig.7 >

<Fig. 8 Mass>

<Fig. 9 different sizes of slabs >

Surface Analysis

As shown in Figure 10, the curve is developed using a G2 (Curvature Continuous). Figure 11 shows Curvature and ZEBRA analysis to understand surface’s smoothness. 

<Fig.10 G2 _Curvature Continuous>



<Fig.11 Surface analysis>



Parametric Shading Devices

Even though the original set of shading devices consists of regular hexagons, in this project, a rectangle set is employed as a basic panel because Lunch box does not provides regular hexagon paneling. The basic set of parametric shading devices is started with 8 points in order to represent its 3-dimensional movement (Figure 13). This is a good way to deal with 3D paneling regardless of the shape of surface such as free form NURBS surfaces. Figure 13-14 shows the modeling process of the shading devices. Figure 15 represents variation of it, and the thickness of 3D panel is directly linked to circles which can control the opening size.



<Fig.12 8 points GH node for paneling>



<Fig.13 Paneling process 1 of 8 points >

<Fig.14 Paneling process 1 of 8 points >





<Fig. 15 Variation of opening size>

Paneling (Curtain Wall & Shading devices)  

This section shows how curtain wall and shading devices can be applied  to a NURBS surface (Figure 16). Lunch Box, a plug-in for exploring paneling in Grasshopper, is used to develop curtain wall and obtain 8 points for shading devices. Three different surfaces are created: inner surface will be a curtain wall, and others (green color surfaces) will provide information of 8 points of each panels. Figure 17 represents two surfaces for the shading devises and 8 points of individual panels, Figure 18 shows overall shape of parametric shading devices. In terms of its parametric relationship,  distance between two NURBS surface determines opening size of shading devices (Figure 20). Based on the result of paneling, 8 points also can be used to develop a parametric frames for curtain wall ( Figure 19).

  <Fig.16 GH for curtain wall>

<Fig.17 Three layers for building components>

<Fig.18 Paneling for kinetic facades using 8 points> 



<Fig. 19 Paneling for curtain wall using 8 points> 

<Fig.20 Variation of facades>

Structure

This building has a unique structure shape (figure 22). The provided points by using Lunch Box can be used to develop the parametric structural shape through data management. As shown in Figure 22, the structural variation is created based on the number of V direction. This means whenever the change of V direction is occurred, the shape of curtain wall, structure, and shading devices is updated automatically.

 <Fig.21 GH for parametric structure>

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<Fig.22 Variation of structure>

Assembly

This model has three parts: curtain wall, structure, and shading devices (Figure 23). All parameters of them can be updated whenever building form and the number of panels is changed.

<Fig.23 Overall assembly of building component>

Parametric Parasol

This is an additional model for parametric parasol by using similar design method (Figure 24). Basic shape of the parasol consists of triangles. The shape of combined triangles can be manipulated by using Kangaroo Physics, a physics engine for Grasshopper. This can be installed outside of building to provide occupants with comfortable outside environment.

<Fig. 24 Parametric parasol>

References

CTUBH 2012. CTBUH 11th Annual Awards - Oborn & Chipchase, “Al Bahar: Innovating the Intelligent Skin”http://www.youtube.com/watch?v=-SSRUlCLUI4.Linn, Charles. Kinetic architecture: design for active envelopes. Images Publishing, 2014.http://www.food4rhino.com/?ufhhttps://www.youtube.com/watch?v=BSEVoFi9MpQ