GMU:Computing with Thread/Part1

Computing with Thread: Part I

Thread Geometry

We explored what kind of geometric constructions we can do with thread, chalk and the help of several people...

We found out...

• how to draw a line
• how to draw a circle ( d = const.)
• how to draw an ellipse ( a + b = const.)
• how to draw multifocal ellipses (a + b + c = const.)
• how to draw egg-shaped curves (3 * a + b = const.)
• how to measure the circumference of a circle
• how to calcualte pi using only thread (See also here)

3D thread geometry

We explored how our thread-based drawing tools could be used to identify points on the surface of shapes in 3 dimensions.

• We discovered the 3d ellipsoid (a + b = const.)
• We found that multifocal 3d ellipsoids have a doughnut-topology.
• We found two different ways to create ellipsoid shapes:
  • the polygon method, where the thread forms a polygon going through the focal points and the drawing point
  • the star method where the thread is alternately visiting each focal point and the drawing point

Observations

• Geometric knowledge from school only got us so far ...
• There is a whole universe of "new" shapes and forms

Questions raised

• Questions regarding surface of different shapes popped up
• We discussed different methods of measuring the surfaces using thread

Homework

• What could an Experimentier-Baukasten / a kit / a sandbox for computing with thread look like?
  Do some research on other kinds of kits!
• Do some thread-based geometry at home. Pick a parameter such as the thread-length and vary it systematically
• Document your thread-art in the wiki

Geometry

Some links to classics of compass + straightedge geometry
as well as the thread-based geometry we explored in our class.

Lines

• Tim Ingold: Lines: a brief history, ISBN 978-0415424271 (hint: google it)
• Kandisky: Punkt und Linie zu Fläche

Ellipses

• Ellipse on Wikipedia
• Multifocal oval curves on Wikipedia
• On the description of oval curves by James Clerk Maxwell
• Semidefinite Representation of the k-Ellipse

Compass and Straightedge

• Compass and straightedge construction on Wikipedia
• Byrne's version of Euclid's elements using coloured shapes (very bauhaus)
• 3D Sculptures by Helen Friel

Kitspiration

Here are some links to all kinds of kits.
May they serve as inspiration for creating your own textile computing kits.

Educational Kits

• Anker-Steinbaukasten
• LECTRON Elektrobaukasten
• LEGO, KNEX, LEGO-Mindstorms ...

Sewing Boxes

• Sewing Box with Implements
• Sewing Box Cabinet by Kiki van Eijk

Tool Boxes

• Survival Kit
• Dentist Toolkit
• Pictures of surgical sets and tool boxes

Portable Textile tools

• The Charkha (spinning)
• Hexagonal Weaving loom (hexagonal weaving)
• Tablet Weaving (weaving/braiding)
• How to make a Kumihimo Disk out of a CD (braiding)

Knots and Splices

Knot History

• various knot books online and offline
• We learned how ropes are made in a "Seilerei" on the "Reeperbahn"
• We learned about a rope inspection machine, that travels along a the cable of a "Seilbahn"

Knot Theory

• We learned the basics of knot theory
• Minimum number of crossings
• Knot-Invariants and Knot-Polynomials

Knot Classification Game

We played a knot identification game.
It goes like this:

• Student A creates two knots using thread.
• Student B tries to figure out whether or not the two knots are the same

Homework

Create a nice framework for displaying knots.
The framework can be physical, graphical or computational in nature

Links

How are threads made?

• Seilforschung: Wie sieht das optimale Seil aus?

Thread Games

• String figures: a study of cat's-cradle in many lands

Self-Assembly

• Teslaphoresis (self-assembly of threads)
• Spontaneous Patterns in vibrated Ball Chains: Knots and Spirals

Knotting

• History and Science of Knots
• Animated Online Encyclopedia of Knots
• Encylopedia of Knots and Fancy Rope Work ISBN 978-0870330216

Unknotting with Force and Magic

• Gordian Knot (mythology)
• Harry Houdini (magician)
• Abbot's encylopedia of rope tricks for Magicians ISBN 978-0486232065
• Self-Working Rope Magic: 70 Foolproof Tricks ISBN 978-0486265414
• Seil-Salabim

Splicing

• Splicing Animated.

Knot Theory

• Knot Theory Videos by Numberphile
• How Mathematics gets into Knots
• Alexei Sossinsky, Mathematik der Knoten: Wie eine Theorie entsteht, ISBN 978-3499609305
• The Knot Atlas
• Historic Knot Tables

Tie Knotting

• More Ties than we thought (paper)
• random tie knot generator

Bondage

• Hojōjutsu japanese martial arts technique
• Shibari arte documentary on japanese bondage
• Go get knotted a blog to learn bondage knots
• Enchanted Forest photo series by Garth Knight

Knot Robot

• Manipulation of Deformable Linear Objects feat. Un-Knotting Bot
• Knotting/Unknotting: Manipulation of Deformable Linear Objects

Braids

In this class we identified the basic elements of braids, and explored the intersection of braiding and sorting algorithms.

Communication game

• We developed and discussed different notations for braiding
• We played a game involving three persons
  • The first person creates a braid
  • The second person describes the structure or construction of the braid using words only
  • The third person recreates the braids accordingly

Observations

• There are different ways to describe the structure of a braid
  • structure vs construction
  • position-based vs thread-based
• Some instructions will not result in a braid
• Some systems are simpler than others, but may not be universal in the sense that they can describe every possible braid

Sorting Braids

• We discussed why sorting is an important topic in computer science
• We got to know the concept of computational complexity and the big-o notation
• We re-enacted several sorting algorithms using threads and chalk
• We developed collaborative sorting algorithms resulting in braids

Observations

• Bubblesort is a fun collaborative activity
• The mapping from sorting operations to operations of textile construction is important
• If the mapping is bad the result may not be a stable (overs and unders)
• If the mapping is bad the result may not be dense (no-ops vs crossings)
• Sorting networks allow for parallel sorting / braiding

Links

Braiding

• French Children's book feat. Maypole Dance + Track Diagram
• Pet Flakes Architecture inspired by Maypole braiding
• Bobbin Dance by Shane Waltener

Sorting

• Sorting Networks by Computer Science Unplugged
• Bubble Sort as hungarian folk dance
• Bubble Sort
• Merge Sort
• Insertion Sort
• Quick Sort

Computational Complexity

• Big-O-Notation
• Big-O-Cheatsheet
• XKCD Cartoon on TSP
• P vs NP

Braiding + Card Weaving

• Braiding in Griswold's Weaving Archive
• Tablet Weaving in Griswold's Weaving Archive

Braiding Techniques

• Loop Braiding
• Braiding Techniques for horses

Braiding Tools

• Online Braiding Tools
• Bead Crochet Software
• Guntram's Tablet Weaving Thingie
• ATARI band weaving book + disk

Rope Weaving

• How to weave a Rope Mat
• Rope Weaving Clinic

Books

• Y. Kyosev, Braiding Technology for Textiles, ISBN 978-0857091352 + ebook version

Nets

In this class we had a look at graphs and networks, both in the textile and the social domain.

Network Analysis

We had a look at knotted networks and discussed possible representations

• We discussed which properties of the textile net are important, and which properties can be abstracted away
• We looked at different ways of creating a network from single pieces of thread or a single continuous piece of thread
• We found that a graph representation may not be a suitable model for textile networks
  • If we care about the network structure, nodes of degree two (a node with two edges) may not be meaningful
  • However nodes of degree two could serve to represent a knots in a single thread
  • We could encode the distance between knots (weight of an edge)
  • If we follow a thread through the network, direction might play a role as well (directed edges)

Network Construction

We wondered how networks can be constructed from a single thread.

• We found that some networks can't possibly be constructed from a single thread
• We had a look at the Seven Bridges of Königsberg, and tried to figure out which conditions need to be met, to find a path that crosses all bridges exactly once (Eulerian path)
• We found there is a complementary graph for people who use a boat and try to cross under all bridges exactly once
• We learned about the classic problems of graph theory
  • Visiting each places / node exactly once in a single tour (Hamiltonian Path)
  • visiting each bridge / edge exactly once in a single tour (Eulerian Path)
  • The Travelling Salesman Problem (TSP)

Regular Networks

We explored various tilings, and the networks that result from their edges.

• We had a look at regular tilings of the plane, and the node degrees of the resulting networks
• We discussed which of the tilings can be turned into networks using a single continuous thread and how to do it
• We had a look at pentagonal tilings of the plane, and the kind of networks that they would yield

Random Networks

• We discussed how we can create networks in a random but controlled manner
  • Using a dice to randomly decide which knots to connect
  • Modify knotting probability based on the degree of a knot
• We learned about the history of small world and scale free networks and their properties

Network Topology

• We learned about graph embeddings, and that some graphs cannot be embedded in the flat plane without edges crossing
• Accordingly some networks cannot be laid out without threads crossing
• Networks may be filled with inflatables to create interesting 3D shapes. (see also: Knitflatables)

Homework

• Find personal, autobiographic or social relations, that are important to you
• Can you represent those as a knotted network?
• Consider the use of knotted networks to store and communicate the flow of resources, family relations etc.

Links

Travelling Salesman Problem

• Travelling Salesman Problem with Thread
• TSP-Art
• TSP-Animation

Paths in Graphs

• Eulerian Path
• Hamiltonian Path

Sorting Networks

• CS-Unplugged
• Sorting Network

Tilings

• Tilings by Convex Regular Polygons
• Penrose Tiling

Knitflatables

• Knitflatable Architecture

Random Networks

• Random Graph
• Scale-free network
• Small-world network
• Boolean Network