Ear. Fungus. Jenga.

  Hello faithful readers! The last few weeks have been busy, but very productive in the world of Biomedical Visualization. Here’s a breakdown:

First and foremost, the ear prosthesis that I’ve been working on for the past several weeks has been cast in silicone and the final touches have been added. Here are a few pictures of the process:

 

Intrinsic Coloring - Front

 

Intrinsic Coloring - Back

 

The whole process was really impressive and the end result blew me away. This was not only my first stab at working with silicone, but the first time working on a sculptural piece since entering the BVIS program. It was a lot of fun getting to work with materials with my bare hands and create something tangible. The process involved mixing several different colors of silicone using my own skin tone. I mixed different silicones to create colors for the base, shadow, helix, cartilage, and a red glaze. The base of each color was achieved by adding small amounts of pigment combined with, of all things, rayon flocking – miniscule fibers of varying color and tone. Who knew?

The red glaze was the first color to be painted into the 3-part mold (shown in my previous blog entry) to give the ear an overall semi-transparent color to simulate vasculature. To make this layer look even more realistic, small pieces of yarn were frayed and split into individual fibers and added, very sparingly, to mimic larger vessels. This first layer was cured, and then the helix color was added, the shadow was painted onto the highest parts of the mold, and the cartilage color was painted into some of the deeper areas. The whole process is “backwards” since you are making a positive silicone object from a negative mold. This made applying the shadow and cartilage layers a bit tricky.

 

Extrinsic Coloring  - Base

 

Extrinsic Coloring - Final

 

After those layers were cured, the base color was used to fill in the rest of the mold, the 3 parts were squeezed together with clamps, and the entire mold went into the kiln to cure. After the silicone set up, the mold was pulled apart, the excess silicone was trimmed flush, and the anterior margin was cut back in order to make a gentle, tapered edge that helps to blend into the face of the patient for a seamless look. Extrinsic coloring was added by mixing pigments with a medical grade silicone, which, oddly enough, resembles bathtub caulking. A few more minutes in the kiln and the process was complete! Weeks of hard work finally paid off with surprisingly realistic ear prosthesis. I couldn’t be happier with the result.

In the Haptics & Augmented Reality class, we just finished our fifth assignment in which we had to programmatically recreate everyone’s favorite block stacking game: Jenga! This is the first half of a two part assignment. Here we had to create Jenga blocks randomly and with varying widths and thicknesses with code alone, rather than importing objects. Once the blocks were generated in the scene, we had to create physical mesh objects in the scene that act as buttons that can be interacted with using the haptic device. Here’s a video:

 

https://vimeo.com/90881412

 

The red sphere acts as a “RESET” button, which randomly regenerates the stack of blocks. The blue sphere acts as a “DESTROY” button by removing two of the blocks making up the base, causing the entire stack to fall. Finally, the green sphere is an “EASY” button and automatically removes half of the stack. There were a number of hang-ups with the project - mostly related to the specific nature in which objects had to be created and imported into the scene in order for them to be identified as physical objects and interact with one another - but would say that it was a success overall. The next project will require using virtual hinge joints in order to create a dynamic “tool” that can be used to grab the blocks and move them in order to accurately simulate the real game. This class has been a crazy head first dive into the very foreign world of coding for me, but I’ve learned a tremendous amount so far, regardless of the blank stare I often have when sitting in front of the lines upon lines of carrots, brackets, asterisks, and jargon on the screen.

I’m also happy to report that I have finally completed our first major project in the Computer Visualization class. The cordyceps militaris model that I have been diligently working on for the past several weeks has finally been rendered, composited, and adjusted!

 

cordyceps militaris

 

The view is from inside the hemocoel of a moth larva in the soil looking up through a rupture caused by the fruiting bodies of the cordyceps fungi. The fungi attaches itself to the cuticle of a larva and extends its hyphae (the thread-like material) into the body. The mold spores proliferate and cover the interior of the insect, slowly deteriorating its immune defenses until the level of toxicity kills it, or its organs fail. The body then acts as a breeding factory for the cordyceps, which continues to grow and proliferate, eventually sprouting a long, white stalk with a bright orange tip that can be seen above ground. I wanted to make the scene look as bleak and ominous as possible, and I think the combination of the camera position, coloring, and the depth/blur effect worked really well together to accomplish that.

3Ds Max is an awesome program and is becoming easier to use with each project. It is an *incredibly* powerful tool, as I’m coming to find out, and when used in tandem with MudBox, the possibilities are literally endless. We just had our first introduction to Mimics Software which can be used to take stacks of CT data and isolate objects of specific densities. Our next project involves using scan data from a human head and isolating the mandible, which can then be imported into Max for further manipulation and texture addition. With these three tools, an artist could take over the world! And I intend to do just that.

More insane rants about world domination to come.