Muhammad Abdullah, Romeo Sommerfeld, Laurenz Seidel, Jonas Noack, Ran Zhang, Thijs Roumen and Patrick Baudisch

Roadkill is a software tool that converts 3D models to 2D cutting plans for laser cutting—such that the resulting layouts allow for fast assembly. Roadkill achieves this by putting all relevant information into the cutting plan: (1) Thumbnails indicate which area of the model a set of parts belongs to. (2) Parts with exposed finger joints are easy to access, thereby suggesting to start assembly here. (3) Openings in the sheet act as jigs, affording assembly within the sheet. (4) Users continue assembly by inserting what has already been assembled into parts that are immediately adjacent or are pointed to by arrows. Roadkill maximizes the number of joints rendered in immediate adjacency by breaking down models into “subassemblies.” Within a subassembly, Roadkill holds the parts together using break-away tabs. (5) Users complete subassemblies according to their labels 1, 2, 3…, following 1  > 1 links to insert subassemblies into other subassemblies, until all parts come together. In our user study, Roadkill allowed participants to assemble layouts 2.4 times faster than layouts generated by a traditional pair-wise labeling of plates.

The Roadkill algorithm proceeds in four steps:

First, Roadkill determines a possible assembly order “in reverse”, i.e., it starts with the fully assembled model and explores ways of removing plates from it, until fully disassembled.

second, Roadkill identifies sequences in the assembly order that cannot be assembled independently from each other and either merges the dependent branches together or splits them off as a subassembly.

thrid, Roadkill creates the 2D layout, by placing connecting plates adjacently. Plates that cannot be placed adjacently (red) are either linked through arrows or designated as subassemblies.

Finally Roadkill creates the design elements (arrows, labels, jigs, etc.) to generate the 2D cutting plan.