# 6.849: Geometric Folding Algorithms: Linkages, Origami, Polyhedra (Fall 2012)

## Prof. Erik Demaine       TA: Jayson Lynch

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 [+] Origami intro: Origami alphabet, higher dimensions. Universality: Terminology history, practical strip folding, pseudopolynomial bounds, seam placement, hide gadget via simple folds? Simple folds: Metal/wood/plastic motivation, definition, examples, linear-time algorithm, extra creases. This class is structured around the many excellent questions that students asked and suggestions they made. There are so many that I've marked a few highlights with stars: ★ Actual folding (we'll fold the numerals 6, 8, 4, 9 from an origami alphabet!) Some history of where a few terms come from. Practical examples of strip folding. Pseudopolynomial bounds on strip folding: what they are and what's (un)known. Seam placement (some skipped content in L02's notes) ★ Open problem about simply folding the hide gadget: let's solve it together! Motivation for simple folds: metal/wood/plastic bending Definition of simple folds: more precise Examples of flat-foldable vs. mingling 1D mountain-valley patterns ★ Algorithm for testing 1D flat foldability in linear time (new -- simpler than textbook!) Making any mountain-valley pattern flat foldable by adding extra creases Higher-dimensional folding
 No support for video detected. Please use an HTML5 browser. Download Video: 360p, 720p Handwritten notes, page 1/5 • [previous page] • [next page] • [PDF] Handwritten notes, page 1/5 • [previous page] • [next page] • [PDF] Slides, page 1/32 • [previous page] • [next page] • [PDF] Slides, page 1/32 • [previous page] • [next page] • [PDF]

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