2013_Q3

Molds for the leg: the story so far

Today I’ve been working on defining the best angle and cutting planes for the molds for the leg.
For this I used a grasshopper script we created to check for undercuts. This script uses a Galapagos block to minimize the amount of undercuts; of course the script should end up finding a orientation for the molds which causes no undercuts.

Sadly, I only partly succeeded. When analyzing the inner surface I found the making of the molds wouldn’t be possible without a few undercuts (and I informed the design group about this.)
Mold leg undercuts
The picture above is a top view of the inner surface, rotated so the undercuts are minimized. The green arrows is where undercuts still happen if we would have to make this part. With the connection methods we’re currently planning to use. So this is the part that should be fixed.

I also came across a similar problem for the filleted edges on the outer surface, but I think that’s is something to discuss we have planned on Monday. (Because I think there might be an easier fix for this.)

Even though the molds will end up to be unmakeable using the current design I decide on how to divide the them. To create actual mold-models from these cut parts Hendrik will be creating a grasshopper file which will also automatically create the needed margin and edges. (Or at least, that’s the plan.)
I have divided the molds like this;
Molds leg

The parts in the previous picture will be milled separately and then be put together to create one big mold for the inner surface and one for the outer surface of the leg. The (small) molds for the bench part will be put together separately. To make it clear, the completely model is currently divided (big-mold wise) like this, with the inner and outer surface separated;
Division model

 

Update [11/03/2014]: the undercut problem has been solved by adjusting the design and the cutting plane for the molds just a little bit. The division for the molds only changed a little bit.

2013_Q3

Former group 3 preliminary

Group 3-1 Group 3-2 Group 3-3 Group 3-4 Group 3-5 Group 3-6

Our “In and Around” design for preliminary. Above are all the rendering in many locations.

Group 3-7

These are the colour test. In the end our conclusion is red.

Group 3-8 Group 3-9

These are the assembling process. The design have to be made out of two part, upper and lower part, which will be laminated together at the edges. After the glue stiffs enough, the edges need to be sanded and painted to get rid of the exposed composite edge.

2013_Q3

Group 4 Presentation “Celtic Knot”

2-CIty_Hall_Plaza

Group 4 presents the Celtic Knot, an iconic structure that can fit everywhere and will function as a meeting spot as well as providing shade.

dimension-3views

It is based, just like the celtic knot, on three repeating patterns, which makes it easy to produce. The design is a combination of a bench and an arch, which connects to the second bench and arch.

explode
The arch and bench itself can be cut into four parts, which each have an inner and outer panel, so only eight molds are needed for the total design, which all will be reused three times.

The complete presentation can be found here.

2-forst-1

2013_Q3

Preliminary design presentation group 2: the dance

‘The Dance’ is meant to be an iconic meeting spot, shelter, rest place which would be modular and buildable.
It would be doable within the 20m² mold restriction and because of it’s modularity it would be easy to create fewer or even more parts and arrange them according to the local demands.

The Dance - Slide1

Click here to download the complete presentation as pdf.

2013_Q3

Minimum bounding box

For creating the molds, it is very useful to find the minimum bounding box for each surface. Grasshopper can use iterative evolutionary models to find the best fitness for a group of parameters (genes).  This method is called Galapagos.

So instead of trying to find a good bounding box, we input the bounding box pivot points axes as genes and use the resulting volume as a minimum fitness.
evo test
In the end you can automatically calculate the mold area you’re using or check the max height requirements.

TODO: Work on extruding to make the actual mold, instead of only the bounding box.

The result with one our of models:

boxes

For more information on Galapagos see:
http://www.grasshopper3d.com/profiles/blogs/evolutionary-principles