Microstructure Model

Goldberg Polyhedron

Goldberg Polyhedron – Bottom

Goldberg Polyhedron – Top

Goldberg Polyhedron – Side

George Hart’s model of Michael Goldberg’s polyhedron has quickly become the “Hello World” of resin printers. I tried to print a half of the model simply because it was in my test folder, not expecting it to print at all.  Surprisingly it came out reasonably well, except that the sides suffer from z-layer bleeding. Several of the holes remained filled with resin – some isopropyl alcohol and some diligent cleaning would sort that out I think. I should note that each square on the mat in the photos is 10mm across.

Failed Goldberg Polyhedron

Even the failed prints look good! Here the print failed to attach to the base and remained on the vat floor for the duration, leaving a 2D projection of the half-sphere.

Microstructure Model

Microstructure Model – Bottom

Microstructure Sphere – Partial – Top

Microstructure Sphere – Partial – Bottom

This model is again from the Functional Representation program. In my search for efficient fill algorithms I came across the work of Alexander Pasko and various colleagues, particularly a paper entitled “Procedural Function-based Spatial Microstructures” (PDF) which details exactly what I was looking for. Since then I have been attempting to recreate their findings, particularly the models with parametrised internal structure. Last week I finally was able to create the model and so of course it was one of the first things I wanted to print. The photo’s do not really do it justice – and there is still a lot of improvements to make – but I was pretty excited to print some resemblence to the model. Below is an image from a later paper, “Procedural Function-based Modelling of Volumetric Microstructures” (PDF) which shows how the model should look. The first image in the gallery above is the model I created, and the photos are of a print of the middle quarter of the sphere, and some of the structure is clearly visible. I plan to write an entire post on this subject as I think there is a lot of potential in relation to 3D printing.

Volumetric Microstructure taken from "Procedural function-based modelling of volumetric microstructures", Alexander Pasko et al.

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