This blog post introduces an algebraic approach to representing and manipulating knitting patterns. It defines a knitting algebra based on two fundamental operations: knit and purl, along with transformations like increase and decrease, capturing the essential structure of stitch manipulations. These operations are combined with symbolic variables representing yarn colors and stitch types, allowing for formal representation of complex patterns and transformations like mirroring or rotating designs. The algebra enables automated manipulation and analysis of knitting instructions, potentially facilitating the generation of new patterns and supporting tools for knitters to explore variations and verify their designs. This formal, mathematical framework provides a powerful basis for developing software tools that can bridge the gap between abstract design and physical realization in knitting.
This blog post by David Weisberg traces the evolution of Computer-Aided Design (CAD). Beginning with early sketchpad systems in the 1960s like Sutherland's Sketchpad, it highlights the development of foundational geometric modeling techniques and the emergence of companies like Dassault Systèmes (CATIA) and SDRC (IDEAS). The post then follows CAD's progression through the rise of parametric and solid modeling in the 1980s and 90s, facilitated by companies like Autodesk (AutoCAD) and PTC (Pro/ENGINEER). Finally, it touches on more recent advancements like direct modeling, cloud-based CAD, and the increasing accessibility of CAD software, culminating in modern tools like Shapr3D.
Hacker News users discussed the surprising longevity of some early CAD systems, with one commenter pointing out that CATIA, dating back to the late 1970s, is still heavily used in aerospace and automotive design. Others shared anecdotal experiences and historical details, including the evolution of CAD software interfaces (from text-based to graphical), the influence of different hardware platforms, and the challenges of data exchange between systems. Several commenters also mentioned open-source CAD alternatives like FreeCAD and OpenSCAD, noting their growing capabilities but acknowledging their limitations compared to established commercial products. The overall sentiment reflects an appreciation for the progress of CAD technology while recognizing the enduring relevance of some older systems.
Autodesk has partially restored older forum posts and IdeaStation content after significant community backlash regarding their archiving. While not all content has returned, and some functionality like search remains limited, the restored material covers a substantial portion of previously accessible information. Autodesk acknowledges the inconvenience the archiving caused and states their commitment to improving the process and platform moving forward, though a definitive timeline for full restoration and improved search functionality is yet to be determined. They encourage users to continue providing feedback.
HN commenters lament the loss of valuable technical information caused by Autodesk's forum archiving, with several noting the irony of a CAD software company failing to preserve its own data. Some praise the partial restoration, but criticize the lack of search functionality and awkward organization within the archive. Others express frustration that Autodesk hasn't learned from past mistakes and continues to undervalue its community knowledge base. The company's reliance on a single employee for the restoration is viewed with concern, highlighting the perceived fragility of the archive. Several suggest alternative archival solutions and express skepticism that Autodesk will maintain the restored content long-term. A recurring theme is the broader problem of valuable technical forums disappearing across the web.
Cal Bryant created a Python script to generate interlocking jigsaw puzzle pieces for 3D models, enabling the printing of objects larger than a printer's build volume. The script slices the model into customizable, interlocking chunks that can be individually printed and then assembled. The blog post details the process, including the Python code, demonstrating its use with a large articulated dragon model printed in PLA. The jigsaw approach simplifies large-scale 3D printing by removing the need for complex post-processing and allowing for greater design freedom.
HN commenters generally praised the project for its cleverness and potential applications. Several suggested improvements or alternative approaches, such as using dovetails for stronger joints, exploring different infill patterns for lighter prints, and considering kerf bends for curved surfaces. Some pointed out existing tools like OpenSCAD that could be leveraged. There was discussion about the practicality of printing large objects in pieces and the challenges of assembly, with suggestions like numbered pieces and alignment features. A few users expressed interest in using the tool for specific projects like building a kayak or a large enclosure. The creator responded to several comments, clarifying design choices and acknowledging the suggestions for future development.
Summary of Comments ( 4 )
https://news.ycombinator.com/item?id=43763614
HN users were generally impressed with the algebraic approach to knitting, finding it a novel and interesting application of formal methods. Several commenters with knitting experience appreciated the potential for generating complex patterns and automating aspects of the design process. Some discussed the possibility of using similar techniques for other crafts like crochet or weaving. A few questioned the practicality for everyday knitters, given the learning curve involved in understanding the algebraic notation. The connection to functional programming was also noted, with comparisons made to Haskell and other declarative languages. Finally, there was some discussion about the limitations of the current implementation and potential future directions, like incorporating color changes or more complex stitch types.
The Hacker News post "Algebraic Semantics for Machine Knitting" (linking to an article about the same topic) generated a moderate discussion with several interesting comments.
Many commenters expressed fascination with the intersection of seemingly disparate fields like abstract algebra and knitting. One commenter highlighted the beauty of finding mathematical structures in unexpected places, echoing a sentiment shared by several others. They found the idea of formalizing knitting patterns with algebraic structures intriguing and intellectually stimulating.
A recurring theme was the potential for this research to improve existing knitting software. Commenters envisioned applications like better stitch visualization, more powerful pattern generation tools, and even automated error correction in knitting designs. One commenter specifically mentioned the possibility of creating software that could translate between different knitting machine formats, a long-standing challenge in the knitting community.
Some commenters with a technical background delved into the specifics of the algebraic structures used, discussing category theory and its potential relevance to this area. They speculated about the practical implications of using these advanced mathematical tools, including the possibility of optimizing yarn usage or creating entirely new knitting techniques.
A few commenters also touched upon the broader implications of this research for craft and technology. They saw this work as an example of how seemingly traditional crafts can benefit from modern computational methods. The idea of bridging the gap between digital fabrication and traditional handcrafts resonated with several commenters, suggesting a growing interest in this intersection.
While there wasn't extensive debate or controversy, a couple of commenters expressed skepticism about the immediate practical applications of the research. They acknowledged the intellectual merit of the work but questioned whether it would lead to tangible improvements in knitting software or techniques in the near future. However, even these skeptical comments were generally respectful and acknowledged the potential long-term benefits of the research.
Overall, the comments reflected a positive reception to the research, with many expressing excitement about the potential applications and the novelty of applying abstract algebra to the craft of knitting. The discussion was insightful and touched upon various aspects of the research, from its technical details to its broader implications for craft and technology.