3. Computer Aided design¶
overview¶
This week I practiced and experimented with different 3D modeling programs, some I had experience working in (Rhino) and others that I did not (Fusion 360). I liked the idea of speed dating, to quickly test out the different programs and understand how they work and whether they are suitable for my way of thinking and working. My goal was to test both programs and think of ways I can work across the two.
Rhino Experimentation¶
I had significant experience working with Rhino. However, I always thought that I could be doing things better, work smarter and not harder. I also never worked parametrically with Rhino, using grasshopper. So that was something I wanted to get into this week.
Having an interest in pure geometry, I always thought Rhino was a good 3D modeling space to think geometrically. This week this was further confirmed. In comparison with Fusion, I felt Rhino was more fluid and I better space to think about geometry. Fusion is better at a later step in the design process when we want to think of materiality, components, motions etc…
Pure Geometry¶
I try to think of Geometry as a language. My method follows past tradition especially arabesque where the artist was engaged in the process of discovery of geometric forms. Take a pentagon. When all vertices are connected a smaller pentagone emerges in the centers. They can continue to infinity, in a process of self-reflection - fractile growth. My interest is to apply this process of discovery three dimensionally. I’m interested in the dodecahedron. This is one of the platonic solids. It’s made up of 12 identical pentagonal shapes, connected into closed volumes. On Rhino I modeled a Dodecahedron by finding the 3D angle through the intersection of three spheres. The intersection of those spheres allowed me to array the pentagon 3 dimensionally.
Now that I have a dodecahedron I can start to investigate this geometry and understand the many relationships it offers. Similar to how on the 2D plane the geometry of the pentagon offers self-similarity and fractile patterns, we can also do the same in 3D. During this process I better understood the concept of dual geometries. In this case the dodecahedrom’s duel is the icosahedron.
After making a scaffolding. Placing each dimension in a layer. I started to play around with forms.
Grasshopper¶
Stepping into a new territory for me was working with grasshoppers. I decided to model a dodecahedron using a grasshopper. Which means finding a mathematical expression of the geometry. This was way beyond my ability at the time - but I found a very helpful tutorial that does just that.
Link: https://www.youtube.com/watch?v=XQTDyWj1ITE
Before that however, I tried something simpler. I modelled an extruded curve parametrically. And learnt to bake the final forms into Rhino. This I thought is incredibly useful for generating new designs and iterating. The grasshopper model can be adjusted and tweaked to produce new and different forms.
Okay for the dodecahedron. I will not get into the details here since I’m still learning. But I was able to follow the steps and pick up the basic logic along the way. What occurred to me is that the construction of parametric models is as much an art as creating a geometry from scratch! Since the same form can be expressed mathematically in different ways. So it will take a while to get this right. But I think best to start with simpler forms and work the way up.
Fusion 360¶
This was my first attempt using fusion. Based on Daniel’s overview and some research, it was clear that fusion is a good software to model precision components and test out mechanical movement rather than create geometry.
Since I’m interested in kinetic design, I decided to follow a tutorial of a gear and slider. This is a design that converts rotary motion into linear motion. I followed the tutorial twice. The first time I messed up with the organization of the components which was not easy to understand at first. Fusion overall structures is more complicated. However I really like the timeline. Which when used right can help archive the sequence of events. I also like sketch mode and the ability to return to the sketch.
The tutorial went through 3 steps.
Building the components of the system Building a base Defining the joins and motion between the components
After following all the steps I managed to make the design and test its motions.
