1. ARCH1291 - Visual Studies II
FALL 2013
Assignment 4: Digitizing Folded Models
ASSIGNMENT INTRODUCTION
This assignment will examine the translation of a developable geometric design from a 2-dimensional paper sheet into a 3-
dimensional folded, or origami, paper form. This form will then be “reverse-engineered” into the digital Rhino 3D environment
through the use of the Microscribe G2X digitizing arms in Lab 813 and the imposition of geometric rules by the student, i.e.
recognizing symmetry, projecting objects to planes, and the use of Rhino’s alignment and set point tool sets.
Just as we used Assignment 1 to realize the space-making opportunities of digital Boolean modeling operations, we will use the
technique of folding to explore the formal and space-making potential of folding 2D planes into developable, 3-dimensional surfaces.
The ensuing digitization process will introduce you to both the challenges and benefits of translating an analog or “hand-based”
design technique into a digital model, from which additional information can be extracted from the geometry. The digitization will be
both an approximation of a real-world object and a method by which you can “perfect” the geometry through the imposition of
geometric rules and grids in Rhino.
Rhino skills for review:
• Mirror
• Rotate Copy
• Layer Organization
• History
New Rhino skills introduced:
• Setup and use of digitizer
• Align
• Set Point
• Curve Through Point
• Surface from Corner Points
ASSIGNMENT RESOURCES
Rhino Primer
• http://openlab.citytech.cuny.edu/12101291coordination/rhino-primer/
Video Tutorial for Assignment 4
• http://openlab.citytech.cuny.edu/12101291coordination/assignment-4-digitizing-folded-models/
Folding Design Options & Diagrams
• http://openlab.citytech.cuny.edu/12101291coordination/folding-diagrams/

2. INSTRUCTIONS
1. Choose one of the provided folded designs from Folding Techniques for Designers and download the corresponding
folding diagram. Print the diagram so that it fills a letter size sheet of paper – otherwise your model will be too small to
easily fold and digitize. You may use folding diagrams other than those provided only if you get approval from your
professor. Great online resources for folding and origami include:
a. http://www.origamitesselations.com/category/diagrams
b. http://www.happyfolding.com/diagrams
c. http://www.origami-instructions.com
2. It will be easiest to begin with a simple letter or tabloid size sheet of office paper, particularly if you start by printing the fold
pattern. Fold your sheet of paper up into a 3D origami form. Be patient as it may take several tries to get it right.
3. Once you have your form folded, secure it to the digitizing table in Lab V813 using clips or drafting tape – one rule about
scanning and digitzing is that the object must remain still while you’re collecting data.
4. Log in to one of the digitizing stations (one is set up for right-hand use and other for left-hand use). Launch Rhino 5 64bit
and issue the “Digitizer” command. Select “Microscribe Digitizer” when prompted to “Select Digitizer.” The light on the
digitizer base should turn green – if the light is not green then contact a CLT for assistance as something may not be
connected properly.
5. Depending on the size and location of your model on the digitizing table you may need to recalibrate the digitizer by
selecting an origin point, an X axis vector, and a Y axis vector, the latter if which Rhino will automatically correct to be 90
degrees off the X axis to create a proper coordinate system.

3. 6. Begin to digitize your form by collecting points at all fold corners of your form. Some origami may have induced curvature,
in which case you may want to collect curve data along that crease. Practice good layer management by placing points on
different layers – the following are a few examples of how you may want to organize your data:
a. Place all points along a curved crease on their own layer
b. Place all corner points that form a planar surface boundary on their own layer
c. Place all corner points that form a sequence of linearly aligned folded edges on their own layer
d. Points may fall into multiple categories, in which case you may want to use nested layers or special color-
coding in addition to layer management. Whatever you do, be systematic about it so that you don’t end up with
a pile of indecipherable points
7. Even if a form has inherent bilateral symmetries, it’s good practice to digitize the entire object. That way, you can locate
the single unit that digitized most accurately and mirror, rotate, or polar array the data to ensure that your digital recreation
is as precise as it can be. You will most likely need to draft a geometrical diagram or construction lines on a separate layer
beneath the scanned data and use them as alignment objects for the digitized data.
8. Once the digitized data has been aligned properly, begin making surfaces. For the most part you will be making planar
surfaces from planar curve boundaries or planar point boundaries but you may find cases where you will be approximating
curved surfaces using surface from edge curve, sweep, or loft tools. In the upcoming surfaces assignment we will go into
further detail on Rhino surface tools, but you will need to get familiar with a few now in order to complete the assignment.
9. Save your Rhino file to your course Dropbox using the proper naming convention. Your final Rhino file for the assignment
should include the following information organized into proper layers:
a. Original digitized point and curve geometry (messy!)
b. Aligned point and curve geometry with construction curves or alignment diagram (clean!)
c. Surface model generated from aligned geometry

4. GRADING
To receive a grade, your Rhino file must be submitted to your Dropbox folder by the beginning of the next class and you must bring
your folded model to class with you to be collected.
Assignment 4 will be graded as follows:
1. Are your files named properly? 10%
2. Did you successfully fold a paper sheet into an origami piece? 20%
3. Does your Rhino file contain the original digitized data? 10%
4. Does your Rhino file contain the aligned digitized data with construction geometry? 10%
5. Does your Rhino file contain a surface model generated by the digitized data? 10%
6. Is the Rhino model a reasonably accurate translation of the original physical object? 20%
7. Are the only naked edges on the outermost boundary of your joined polysurface? 10%
8. Are your surface normals pointing upward (or outward) from the model? 10%
9. Did you fold and digitize a second model? 25% EC