Slipped and tucked stitches introduce small areas of deformation that compound and result in emergent textures on knitted fabrics. When used together with color changes and ladders, these can also produce dramatic colorwork and openwork effects. However, designing slip and tuck colorwork patterns is challenging due to the complex interactions between operations, yarns, and deformations. We present KnitScape, a browser-based tool for design and simulation of stitch patterns for knitting. KnitScape provides a design interface to specify 1) operation repeats, 2) color changes, and 3) needle positions. These inputs are used to build a graph of yarn topology and run a yarn-level spring simulation. This enables visualization of the deformation that arises from slip and tuck operations. Through its design tool and simulation, KnitScape enables rapid exploration of a complex colorwork design space. We demonstrate KnitScape with a series of example swatches.

In chart-based programming environments for machine knitting, patterns are specified at a low level by placing operations on a grid. This highly manual workflow makes it challenging to iterate on design elements such as cables, colorwork, and texture. While vector-based abstractions for knitting design elements may facilitate higher-level manipulation, they often include interdependencies which require stitch-level reconciliation. To address this, we contribute a new way of specifying knits with blended vector and raster primitives. Our abstraction supports the design of interdependent elements like colorwork and texture. We have implemented our blended raster/vector specification in a direct manipulation design tool where primitives are layered and rasterized, allowing for simulation of the resulting knit structure and generation of machine instructions. Through examples, we show how our approach enables higher-level manipulation of various knitting techniques, including intarsia colorwork, short rows, and cables. Specifically, we show how our tool supports the design of complex patterns including origami pleat patterns and capacitive sensor patches.

New digital fabrication workflows require both software development and digital/physical material exploration. To support digital fabrication workflow development, we contribute infrastructure that prioritizes extensibility and iteration. Dynamic Toolchains are dataflow programs with event-driven feedback between interactive, stateful modules. We contribute a browser-based dataflow environment for running Dynamic Toolchains, a library of fabrication-oriented front- and back-end modules for design and machine control, and a development framework for building custom modules. Furthermore, we show how our infrastructure supports unconventional fabrication workflows with demonstrations that include interactive watercolor painting, map plotting, machine knitting, audio embroidery, textured 3d printing, and computer-controlled milling. These demonstrations show how our infrastructure supports multiple kinds of engagement including reuse, remix, and extension. Finally, we discuss how this work contributes to broader conversations in HCI on creativity across the digital/physical divide.

As digital fabrication machines become widespread, online communities have provided space for diverse practitioners to share their work, troubleshoot, and socialize. These communities pioneer increasingly novel fabrication workflows, and it is critical that we understand and conceptualize these workflows beyond traditional manufacturing models. To this end, we conduct a qualitative study of #PlotterTwitter, an online community developing custom hardware and software tools to create artwork with computer-controlled drawing machines known as plotters. We documented and analyzed emergent themes where the traditional interpretation of digital fabrication workflows fails to capture important nuances and nascent directions. We find that #PlotterTwitter makers champion creative exploration of interwoven digital and physical materials over a predictable series of steps. We discuss how this challenges long-running views of digital fabrication and propose design implications for future frameworks and toolkits to account for this breadth of practice.

We present Jubilee, an open-source hardware machine with automatic tool-changing and interchangeable bed plates. As digital fabrication tools have become more broadly accessible, tailoring those machines to new users and novel workflows has become central to HCI research. However, the lack of hardware infrastructure makes custom application development cumbersome. We identify a need for an extensible platform to allow HCI researchers to develop workflows for fabrication, material exploration, and other applications. Jubilee addresses this need. It can automatically and repeatably change tools in the same operation. It can be built with a combination of simple 3D-printed and readily available parts. It has several standard head designs for a variety of applications including 3D printing, syringe-based liquid handling, imaging, and plotting. We present Jubilee with a comprehensive set of assembly instructions and kinematic mount templates for user-designed tools and bed plates. Finally we demonstrate Jubilee's multi-tool workflow functionality with a series of example applications.