Posts in category Week 4

Week 4 recap

This week we focused on production techniques, yet not all of them proved to be possible to produce. In the background we also finished up processing all of the CT scans, of which an overview article will follow next week.

To begin with, we made multiple 3D prints: plaster prints of all of the loose pieces and a tryout of structural solutions in Ultimaker2. The first one we decided to translate into a game during the science fair, while the second one was primarily made for the mid-project presentation. Moreover, we made a form with a CNC milling machine which was later used for vacuum forming. This proved to be the cheapest, easiest and the most user friendly object so far.

Plaster print
Structural solution
DSC_0376 DSC_0375
CNC milling and vacuum forming
DSC_0377 DSC_0378 DSC_0379

Secondly, we discarded paper printing as a possibility due to two main reasons:

  1. Our files were too large to be opened in multiple programs with which we could have given the surfaces color;
  2. The delivery times were too long

This led us to choosing another form which would work the best in the Connex printer. Yet that would lead to rather large expenses, exceeding 100 euros per object. What is more, using soft materials would mean that we strive more for a visual than a functional prototype, since the objects could not withstand warm drinks or even a dishwasher. However, some of this could also be achieved by simply printing the different materials apart in the Ultimaker2. Simply put, we are still struggling to determine what fidelity level we are looking for and what each prototype can achieve. Moreover, instead of having a single idea to work out we actually multiple interpretations of the same object:

  1. Cheap, everyday object (vacuum form)
  2. Object focusing on the aesthetics of historical footprint/3D printing (Connex prints/plastic injection molding)
  3. A game, interactive cup (plaster print of shards)

In other words, it means that the objects form their own trajectories and cannot be easily compared with each other.

To conclude, we now have to focus on what precisely we want to achieve in these trajectories and how to do it using rapid prototyping techniques. That is not what we planned during the first week, but that will lead to more evenly divided workflow and, hopefully, more interesting results.

Comparison of image processing software 3

After multiple emails and a Skype talk we finally acquired a trial version of Mimics. According to their representative, the program is mainly focused at medical uses. Most importantly how do bones, implants react to friction and temperature changes.

This got us interested, since this was also rather important in our project: we were using CT scans to determine the break-line positions and in the end also fill up the missing shards with (possibly) other materials. In other words, it would be very interesting to see how different connections between materials would influence the durability of the object. I must add, that this is only a presumption after a talk with their representative and we might not be able to go so deep in the subject due to the time limitations. Yet this could be very interesting as a research subject for future students.

Having only a week of work left till the presentation, we decided to only  check what were the possibilities of the translation (CT-scans to .stl) procedure and if the results could be better than from Avizo.

The interface seemed clear, but more limited to what was offered at the latter program. It seemed actually very similar to already mentioned Seg3D, which is also focused on medical use.

Interface of Mimics

Interface of Mimics

After comparing multiple objects we came to conclusion that this program does not offer better translation. The meshing is coarser and even though the stepping is less visible, so are the break lines.

hagrid rhino

In conclusion, this program might offer higher possibilities going deep into material interaction(3-matic research), but for simple .stl translations Avizo is still the best option.

P.s. For post processing use MeshLab (open source!): there you can both reduce the fineness of the mesh and smooth it.

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