Exploratory fabrication techniques present new challenges for the reproducibility of small scale automation workflows. In this short paper, we investigate how to repeat, reproduce, and remix exploratory 3D printing workflows. Motivated by challenges in existing online communities, we introduce a platform for sharing computationally fabricated objects. We then propose strategies to support replicability that adapt common end-user programming tools to fabrication. These include ‘diff’ tools for comparing code and its corresponding physical output across iterations, linting tools to communicate process details found through material testing, and remix graphs to facilitate the discovery of relevant models. Through the production and reproduction of several example artifacts across various machines and materials, we demonstrate how our platform supports replication of exploratory workflows. Based on our work, we discuss how to close the loop between exploratory digital fabrication tools and community.

a reproduction of a tactile graphic made through thermoforming over the original.Images from the National Braille Press [29].

This paper presents a reflection on the role of ontological inquiry in HCI research and practice. Specifically, we introduce philosopher Gilbert Simondon’s proposal of technical mentality, an onto-epistemology based on direct knowledge of technical objects and systems. This paper makes the following contributions: an analysis of Simondon’s ontological critique and its connection to technical mentality; a reflection on the ethical and practical implications of Simondon’s proposal for systems research; an example of technical mentality in practice; and a discussion of how technical mentality might be extended into a design program for HCI through four principles: extension, integration, legibility, and expression.

Experimental digital fabrication workflows are increasingly common in human-computer interaction research, but are difficult to reproduce. We present Tandem, a software library that lets a fabricator implement an end-to-end fabrication workflow as a computational notebook program that others can run to physically reproduce the workflow. Tandem notebook programs read and write to CAD and CAM software, project augmented reality interfaces onto machines for manual interventions, and directly control fabrication machines. Fabricators can also denote potential mismatches between the physical and the digital as explicit assertions in code. Using two-sided CNC milling as an example, we demonstrate how to implement a complex workflow as a single program that can be re-run by others while supporting quality control and improving reproducibility.

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.

Understanding how professionals use digital fabrication in production workflows is critical for future research in digital fabrication technologies. We interviewed thirteen professionals who use digital fabrication for the low-volume manufacturing of commercial products. From these interviews, we describe the workflows used for nine products created with a variety of materials and manufacturing methods. We show how digital fabrication professionals use software development to support physical production, how they rely on multiple partial representations in development, how they develop manufacturing processes, and how machine control is its own design space. We build from these findings to argue that future digital fabrication systems should support the exploration of material and machine behavior alongside geometry, that simulation is insufficient for understanding the design space, and that material constraints and resource management are meaningful design dimensions to support. By observing how professionals learn, we suggest ways digital fabrication systems can scaffold the mastery of new fabrication techniques.

Digital fabrication machines are controlled through code. Software that generates this code, such as slicers, often rely on abstractions that restrict practitioners from exploring the full design space. We contribute Vespidae, a programming framework for developing custom toolpaths and visualizations. Vespidae module types include Toolpaths, Actions, Solvers, and Export. These generate geometry, specify machine tasks, sort and visualize action sequences, and generate and stream machine code. We show example workflows that demonstrate Vespidae’s strengths in supporting iteration and unconventional practice. These include non-planar 3D printing, varying a print’s tactile qualities with under-extrusion, and exploring the design space of milling marks. Furthermore, we used Vespidae over the course of six months to explore multi-material 3D printing for energy storage devices on a custom machine. Finally, we discuss how Vespidae contributes to a movement in HCI arguing for human-machine collaboration.

Digital fabrication practice such as 3D printing has increasingly moved into home and hobbyist environments. Beyond running machines, practitioners in these settings undertake maintenance and repair. However, acquiring the skills necessary for machine maintenance is a non-trivial process contingent on experience, equipment, and materials. We seek to better understand how practitioners develop the skills necessary to maintain their 3D printers. We collect interview and survey data from active members of online 3D printing communities to conceptualize themes to characterize current maintenance practice. We find that maintenance is core to our participants’ 3D printing practice: practitioners develop maintenance routines that formalize tacit understandings of fabrication processes, advance expertise during required acts of repair, and rely on hands-on testing to reconcile differences between physical prints and digital models. Given our findings, we argue for considering maintenance as a core part of digital fabrication, and discuss implications for the design of future digital fabrication systems.

Creative coders create programs that generate visual output. Frameworks such as p5.js support sketching with creative code. Given the focus on expressivity over functionality, code reuse in creative coding practice is distinct from other programming contexts. Remixing facilitates iteration on existing code, but we have yet to understand how creative coders use remixing in practice. To understand creative coder remixing strategies, we studied the community of OpenProcessing, a site dedicated to sharing code-generated artworks. We found that 30% of the 1.2 million sketches in our data set were involved in remixing. For in-depth insight, we qualitatively analyze source code and visual output of 350 antecedent-remix pairs. We present on the diversity of ways that authors remix to curate projects, annotate process, explore variations, and transform existing sketches. We discuss the prevalence of these types and implications for supporting a multiplicity of remixing strategies in creative work.

The digital codification and measurement of food preparation has made strong contributions to HCI food research, whether through ingredient manipulation, workflow management, or recipe interaction. But prior work has shown that technical developments that emphasize precise gourmet practices tend to overlook the importance of cultural knowledge. Drawing on an integrative autobiographical design approach, we describe an open-source hardware toolkit that we developed to examine the process of integrating precision techniques with ritual cooking practices across three recipes: flour skin, rice wine, and doufu. Our work points to the importance of understanding precision as a cultural process with roots in personal and familial experience. We end with a reflection on the particular knowledge-forms that come from cultivating cultural relationships to fabrication processes and their implications for reading digital fabrication processes as meaningfully relational.

Digital fabrication in industrial contexts involves standardized procedures that prioritize precision and repeatability. However, fabrication machines are now available for practitioners who focus instead on experimentation. In this paper, we reframe hobbyist CNC milling as writing literate programs which interleave documentation, interactive graphics, and source code for machine control. To test this approach, we present Imprimer, a machine infrastructure for a CNC mill and an associated library for a computational notebook. Imprimer lets makers learn experimentally, prototype new interactions for making, and understand physical processes by writing and debugging code. We demonstrate three experimental milling workflows as computational notebooks, conduct a user study with practitioners with a range of backgrounds, and discuss literate programming as a future vision for digital fabrication altogether.

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.

DIYbio challenges the status quo by positioning laboratory biology work outside of traditional institutions. HCI has increasingly explored the DIYbio movement, but we lack insight into sites of practice such as community biolabs. Therefore, we gathered data on eleven community biolabs by interviewing sixteen lab managers and members. These labs represent half of identified organizations in scope worldwide. Participants detailed their practices and motivations, outlining the constraints and opportunities of their community biolabs. We found that lab members conducted technically challenging project work with access to high-end equipment and professional expertise. We found that the unique nature of biowork exacerbated challenges for cooperative work, partially due to the particular time sensitivities of work with living organisms. Building on our findings, we discuss how community biolab members are creating new approaches to laboratory biology and how this has design implications for systems that support non-traditional settings for scientific practice.

Machine settings and tuning are critical for digital fabrication outcomes. However, exploring these parameters is non-trivial. We seek to enable exploration of the full design space of digital fabrication. To identify where we might intervene, we studied how practitioners approach 3D printing. We found that beyond using CAD/CAM, they create bespoke routines and workflows to explore interdependent material and machine settings. We seek to provide a system that supports this workflow development. We identified design goals around material exploration, fine-tuned control, and iteration. Based on these, we present p5.fab, a system for controlling digital fabrication machines from the creative coding environment p5.js. We demonstrate p5.fab with examples of 3D prints that cannot be made with traditional 3D printing software. We evaluate p5.fab in workshops and find that it encourages novel printing workflows and artifacts. Finally, we discuss implications for future digital fabrication systems.

Digital fabrication courses that relied on physical makerspaces were severely disrupted by COVID-19. As universities shut down in Spring 2020, instructors developed new models for digital fabrication at a distance. Through interviews with faculty and students and examination of course materials, we recount the experiences of eight remote digital fabrication courses. We found that learning with hobbyist equipment and online social networks could emulate using industrial equipment in shared workshops. Furthermore, at-home digital fabrication offered unique learning opportunities including more iteration, machine tuning, and maintenance. These opportunities depended on new forms of labor and varied based on student living situations. Our findings have implications for remote and in-person digital fabrication instruction. They indicate how access to tools was important, but not as critical as providing opportunities for iteration; they show how remote fabrication exacerbated student inequities; and they suggest strategies for evaluating trade-offs in remote fabrication models with respect to learning objectives.

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.

Digital fabrication machines for makers have expanded access to manufacturing processes such as 3D printing, laser cutting, and milling. While digital models encode the data necessary for a machine to manufacture an object, understanding the trade-offs and limitations of the machines themselves is crucial for successful production. Yet, this knowledge is not codified and must be gained through experience, which limits both adoption of and creative exploration with digital fabrication tools. To formally represent machines, we present Taxon, a language that encodes a machine’s high-level characteristics, physical composition, and performable actions. With this programmatic foundation, makers can develop rules of thumb that filter for appropriate machines for a given job and verify that actions are feasible and safe. We integrate the language with a browser-based system for simulating and experimenting with machine workflows. The system lets makers engage with rules of thumb and enrich their understanding of machines. We evaluate Taxon by representing several machines from both common practice and digital fabrication research. We find that while Taxon does not exhaustively describe all machines, it provides a starting point for makers and HCI researchers to develop tools for reasoning about and making decisions with machines.

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.

Digital fabrication is changing the way we design and manufacture the objects around us. Digital fabrication machines enable mass-customisation. However, customising the machines themselves requires a high amount of expertise, which prevents even advanced users from taking part in the creation of bespoke fabrication tools. We present Fabricatable Machines, an open-source toolkit for designing custom fabrication machines. We designed a linear motion module, The Fabricatable Axis, that provides robust automated linear motion. The Fabricatable Axis can be resized, adjusted, and fabricated from different materials. Users can build machines by combining multiple axes. We optimised the design of the axis to be manufactured using a CNC mill, with few externally sourced parts. We observed users creating machines including portable milling machines, 3D printers, and pipe inspection robots using the Fabricatable Machines Toolkit.

We present LamiFold, a novel design and fabrication workflow for making functional mechanical objects using a laser cutter. Objects fabricated with LamiFold embed advanced rotary, linear, and chained mechanisms, including linkages that support fine-tuning and locking position. Laser cutting such mechanisms without LamiFold requires designing for and embedding off-the-shelf parts such as springs, bolts, and axles for gears. The key to laser cutting our functional mechanisms is the selective cutting and gluing of stacks of sheet material. Designing mechanisms for this workflow is non-trivial, therefore we contribute a set of mechanical primitives that are compatible with our lamination workflow and can be combined to realize advanced mechanical systems. Our software design environment facilitates the process of inserting and composing our mechanical primitives and realizing functional laser-cut objects.

Digital fabrication machines (such as laser cutters or 3D printers) can be instructed to produce any part geometry within their application space. However, machines' application spaces are not easily modified or extended. How can we enable the production of application-specific computer-controlled machines by machine building novices? How can we facilitate rapid prototyping of rapid prototyping tools? We propose a novel set of modules, the Cardboard Machine Kit, for the construction of digital fabrication machines. These open-source modules are implemented using cardboard frames, stepper motors, and networked electronics controlled through a Python library. We evaluated the kit both through machine building workshops and by studying the usage of the kit in the wild. In the wild we observed more than 500 novice machine builders who built 125 different machines for 15 different application types. We argue that this breadth demonstrates the efficacy of this modular approach. Finally we discuss the limitations of the Cardboard Machine Kit and discuss how it could inform future machine building infrastructure.

We present a case study of Popfab, a portable multi-purpose digital fabrication tool. It is uses interchangeable heads (3D printer, CNC mill, and CNC knife) on a general-purpose motion platform that folds into a briefcase. Popfab contributed to the discussion of the future of digital fabrication tools by demonstrating the feasibility of both portability and both additive and subtractive manufacturing on a single platform. Portability is not yet a widely considered option for digital fabrication tools, but with Popfab we demonstrate that general site-specific personal fabrication is possible.

We propose a system for both the customisation and the physical representation of instant messaging contacts as hanging tangible avatars which have been outfitted with a personalized skin and set of interactions. Hangsters create an ambient display of a user's online contacts which is simultaneously peripheral and interactive. The user creates a representation of herself in an online avatar creator. The personalised skin is packaged around a standard modular electronic kit and mailed to the recipient. The Hangster then embodies the interactions that would otherwise take place onscreen: on/offline presence and accepting/initializing conversations. The system allows for a more ambient display of a user's contacts while introducing customisable modular electronic toolkits for the tangible avatars.