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It's parametric! (do do do do Do do)

A project log for The Metabolizer

A living recycling center that eats trash and sunshine and poops recycled plastic objects

sam-smithSam Smith 09/21/2018 at 18:050 Comments

This is my friend Dallas Swindle (yes, that's his real name). Dallas does parametric design using Rhino/Grasshopper, a skillset I am deeply envious of. Luckily for me, Dallas is a cool guy who was kind enough to donate his time and extremely specialized skillset to my cause.

"Parametric Design" is still a rather new concept, but it's disruptively useful, and if you don't know about it, you should! It's basically a way of doing 3D modeling where instead of modeling something like you would in say, Sketchup, creating a static model, you instead define a series of relationships and parameters, and let the computer generate a model based on those relationships and parameters.

I wanted to build a helical wind turbine made of stacked, offset sheets of plastic, but in sketchup, at least with my skillz, there was no easy way to do that except by rotating each layer individually, one at a time, which is not only intensely tedious, it also makes it functionally impossible to see what small changes to the parameters have on the overall shape. If I want to see what a 2 degree offset looks like, rather than a 3 degree offset, for example, I have to do it all over again. 

With Grasshopper (a third-party plugin for Rhino that has now been incorporated into Rhino's codebase) all you need to do is slide a slider back and forth, and you can watch your model change in real time. That is, of course, IF you have Rhino, a hella-fast computer, and a knack for abstract problem-solving.

Luckily for me, Dallas has all of those things! He also showed me a really cool website called ShapeDiver, which is kinda like thingiverse- it's a place where you can upload your grasshopper sketches for other people to use. 

The neat thing about it tho is that it let's you play with all the parameters defined in the sketch within your browser, without needing to own the expensive software that is required to actually build the sketch. That lowers the barrier to parametric design considerably!

We're working towards building a sketch that not only lets people define the parameters, but also flatten them, pack them into user-defined sheets, and generate cut-files that can be used to fabricate the parts using a CNC router or laser cutter. We're not there yet, but we're getting close!

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