Hack the City

Hack the City is a series of events in Sheffield about using open data for a better urban and civic experience. Their next hackathon is taking place this Saturday 10th January 2015, and we will be teaming up with the Live Coding Research Network to bring a diverse team of live coders and textile artists together to turn open data into performances, knitwear and whatever else we can think of, as counterpoint to the more conventional hackathon activities such as app building.

Participants include:

  • Antonio Roberts (aka hellocatfood; Birmingham), live coder of glitch art reknown
  • Amy Twigger Holroyd (University of Leeds), not only a knitter but a reknitter, who uses knitting techniques to rework existing, often machine-made garments
  • Nora o Murchu (University of Limerick), whose new Open Source Aran project fits this event perfectly
  • Francesca Sargent (Falmouth), part of FoAM Kernow and hacker on our Weaving Codes, Coding Weaves project
  • Joanne Armitage (University of Leeds), composer and PhD candidate with research interests which include in haptic/vibrotactile feedback in music performance
  • Shelly Knotts (University of Durham),  live coder, composer and curator in network and algorave music
  • Holger Ballweg (Northumbria University) from the German live coding band Benoit and the Mandelbrots of legend
  • Rodrigo Velasco (University of Leeds) is a practitioner of on-the-fly codepoetry and live coding, on a research visit from Mexico City.
  • Helen Thornham (University of Leeds) is a researcher and ethnographer whose interests include transformative use and appropriation of new media, and feminist new media theory.
  • Sam Meech (Manchester) is an artist, videosmith and knitter whose many projects include knitting digital.
  • Victoria Bradbury (CRUMB, Sunderland) is a new media artist working in the intersections between code, body and object.
  • Plus myself Alex McLean (University of Leeds), live coder and so on.

We hope our participation in this event will beget strange and wonderful surprises, which we will develop towards a standalone Code and Craft Hackathon in the future.


Coding with threads: Tablet loom

Tablet weaving is an ancient form of pattern production using cards which are rotated to provide different sheds between warp threads. It’s used to produce long strips of fabric, or the starting bands and borders that form part of a larger warp weighted weaving. We’ll come to the second use later in the weaving codes project.

Tablet weaving

There are quite a few programs around to simulate the tablet weaving process – I used this program to get an initial understanding, here’s an example screenshot:


Continue reading Coding with threads: Tablet loom

Coding with threads: Frame loom

After writing the 4 shaft loom simulation the next job was to try weaving the structures with real threads. Would I be able to replicate the predicted patterns and structures? Ellen warned me that the meander weave would result in unstable fabric, but it would depend on the nature of the material used so was worth trying. Originally I planned to warp up the Harris loom but I need to work up to that as it’s a big and complex job, so I quickly built a frame loom with some bits of wood and nails at 5mm intervals to hold the warp in place.

A simple frame loom

Here you can see it set up with the all important first ‘shed’ (name given to the gap between subsets of warp theads), which defines the order of the threads. I packed the warp too tightly and messily so this was important – luckily as the yarn colours alternate so it made it easy to make.

'sleying' the warp

Continue reading Coding with threads: Frame loom

Dyadic device: a 4 shaft loom simulation.

On the train back from the Sheffield codingweaves workshops back in October I wrote a quick browser program to attempt to further understand the relationship between structure and pattern in weaving – which I’ve put online here. This works in the inverse of how we’ve been writing weaving simulation programs so far. Instead of defining the pattern you want directly, you are describing the set up of a 4 shaft loom – so the warp threads that each of 4 shafts pick up in the top row of toggle boxes, then which shafts are picked up for each weft thread as the fabric is woven on the right.

This involved writing a program that is based closely on how a loom functions – for example calculating a shed (the gap between ordered warp thread) by folding over each shaft in turn and or-ing each warp thread to calculate which ones are picked up. This really turns out to be the core of the algorithm – here’s a snippet:

;; 'or's two lists together:
;; (list-or (list 0 1 1 0) (list 0 0 1 1)) => 
;; (list 0 1 1 1)
(define (list-or a b)
   (lambda (a b)
     (if (or (not (zero? a)) (not (zero? b))) 
        1 0))
   a b))

;; calculate the shed, given a lift plan 
;; position counter.
;; shed is 0/1 for each warp thread: up/down
(define (loom-shed l lift-counter)
   (lambda (a b)
     (list-or a b))
      (length (car (loom-heddles l)))
      (lambda (a) 0))
   (loom-heddles-raised l lift-counter)))

I’ve become quite obsessed with this program, spending quite a lot of time with it trying to understand how the loom setup corresponds to the patterns. Here are some example weaves that you can try. Colour wise, in all these examples the order is fixed – both the warp and the weft alternate light/dark yarns.


This is tabby or plain weave – the simplest and strongest weave (used for sails and hard wearing fabric). The striped pattern is a result of this alternating colour order.

Continue reading Dyadic device: a 4 shaft loom simulation.

Learning about thinking and weaving in Leeds and Sheffield

The second week of intense work on weavingcodes/codingweaves took place in the north of England, and began with a talk at the New Mechanics Institute show and tell meeting in Leeds. This was a good place to pick up from the previous week in Denmark as it included a talk on pixel art from the early days to contemporary forms that had many similarities with our slides.


Continue reading Learning about thinking and weaving in Leeds and Sheffield

Learning to read, notate and compute textiles in Aarhus

Setting off from Copenhagen, the weaving codes tour continued as Emma Cocker, Alex McLean, Ellen Harlizius-Klück and I sped across the Danish countryside on the train. We were heading for Aarhus to spend some time working with people at the other end of the technology spectrum – The Center for Participatory IT in Aarhus University.

We were invited by Geoff Cox to run a workshop over two days, and given the nature of the faculty and time working together being at a premium on this project, we decided to to run the workshop more as invitation to join in our work (and therefore learn a bit about how artistic research is done), rather than having specific material to cover.

Workshop participants working in Aarhus Lots of pieces of woven fabric Continue reading Learning to read, notate and compute textiles in Aarhus