# It's a Bird! It's a Crane! It's&#133;an Airbag!

July 7, 2004

Origami is a Japanese paper-folding art dating back centuries. Engineers are now using the rules of this craft in technological and industrial applications. Unfold origami's secrets:

Origami is best known for its delicate paper bird varieties. However, with each generation of enthusiasts, designs become more complicated, breathtaking, and scientifically engineered. Besides flying to new aesthetic heights, origami's unique set of laws is helping mathematicians solve technical puzzles and stretch engineering boundaries.

Origami is derived from the Japanese words ori, meaning to fold, and gami, meaning paper. One of the fundamental rules of origami is that the paper cannot be glued together, or more importantly, it cannot be cut or torn in anyway. These are exactly the challenges that engineers face when packing space gear into a rocket or putting an airbag into a car's steering wheel.

In the last decade, engineers have invoked the wonders of origami sekkei, another name for computational or technical folding, to assist with such problems. Sekkei involves a combination of geometry, mathematical theories and algebra.

Robert Lang, a former laser physicist in Alamo, California, is now a full-time origami master. Having practiced origami for over 30 years and written several books on the subject, he also serves as a consultant for industry leaders. By harnessing the mathematical concepts behind each design, he has designed software called TreeMaker that computes the folds for just about any given shape.

So how does this apply to more practical matters? These same equations can be used on any object with a flat surface area that needs to be reduced in size without damage. Lang's origami expertise has been used in small electronics and medical equipment.

Two of his better-known projects include airbags and space telescopes. A German car manufacturer needed a way to scrunch an airbag into a small chamber in the steering wheel. Lang used an origami algorithm called the "universal molecule" to dictate how to flatten the set of polygons of the airbag. After the prototype was designed, a computer simulation erased the need for crash tests.

Lang's next challenge was to fit a gigantic telescope inside a rocket. Origami offers suggestions as to folding antennas and solar sails for future spacecrafts, but this telescope's lens, developed by Rod Hyde and Sham Dixit at the Lawrence Livermore National Academy, was extremely fragile. Named the Eyeglass, it will have 40x the magnification capability of Hubble. Its final design will ingeniously fold out like an umbrella.

Advances on the medical horizon are being sparked by origami. Erik Demaine, a professor at MIT of electrical engineering and computer science, is studying protein folding that may lead to disease. He theorizes that origami can teach bioengineers how to attack "bad folds" that are associated with cancer, Alzheimer's disease, and cystic fibrosis.

Researchers at IBM are also looking into this matter. Success in these endeavors will be more likely as supercomputers become faster and can compute the lengthy notations that describe origami folds. In the meantime, origami offers a visual understanding of the folding process, which helps researchers a lot.

Dr. David Huffman, who died in 1999, taught computer science at University of California–Santa Cruz. He started folding in the 1970s, his specialty being curves, repetition of 3D shapes, and spirals. He knew that the designs could be turned into algebraic rules, and spent much time studying the relationship of angels at the folds. Lang recently discovered his work and hopes to embellish his theories.

In spite of its plethora of applications, Lang predicts that it would be difficult to populate an origami bandwagon. He admits the art is esoteric in that it demands both mathematical skill and creativity as well. But as computers get faster and the rules of origami are accessible to engineers of every level, the possibilities will infinitely increase.

Sources:

Margaret Wertheim
New York Times, June 22, 2004
http://www.nytimes.com/2004/06/22/science/22orig.html

Computational Origami: Ancient art find industrial, medical uses
Bob Brewin
Computer World, May 10, 2004
http://www.computerworld.com/softwaretopics/software/appdev/story/0,10801,92956,00.html

Origami Astronomy: The Art and Science of a Giant Folding Space Telescope
Robert Roy Britt