Revealed

A blog about scientific and medical visualization and all that’s involved.

Posts Tagged ‘model’

Modeling Lung Anatomy

Posted by Janet on August 8, 2009

*3ds Max lung model © Denoyer-Geppert, images used with permission.

Following “Visualizing Lung Anatomy,” I can now begin to model the lung. First, I took screen shots of the lung in VolView in three orthographic views–top, left, and front. Then I set up three orthographic planes and added each image as materials to the planes. I prefer this method over using a background image because this allows you to see the images in perspective views as you rotate objects. You also don’t have to worry about shifting your objects and locking zoom, which in my version of 3ds Max gets a little quirky.

LungModel1

Next, I put more planes in the scene, took a screen shot of every twentieth slice from the data set, and applied the screen shots to the planes as materials. Now that I have slices of the lung from front to back, I outlined each slice in the front viewport. Notice that the outlines are all located on the same plane. This will be fixed later. (If you are wondering why the “right” lung is on the left side, it’s because the “person” is facing us so their right is our left.)

LungModel2LungModel3LungModel4

Once the outlines are complete, I calculated the distance I must offset each line in order for it to fit the profiles correctly. After the outlines are moved to their correct positions, you can clearly see the shape of a lung in the perspective view. The lines must be linked together in order for a surface to be created. I selected one outline and used the “Attach Multiple” option under the modify panel. For now, I keep the front and back halves separate so I can easily hide the back side when necessary. Then, using the “Connect” and “Refine” features under the modify panel, I connected vertices between the outlines.

LungModel5

Here is what the model looks like with connections between the outlines:

LungModel6

Using the “Surface” modifier, I created a surface using this mesh. At this point it’s not perfect. I must go back and adjust the mesh until the entire surface can be covered:

LungModel7

A model of the lung without holes in the model:

LungModel8

The lung is looking nearly perfect, but overall still appears rough. Adding “Relax” and “TurboSmooth” modifiers will help refine the mesh:

LungModel9

This is one way to make a model of the human lung. I chose this method because I wanted to capture the accuracy in shape and had tools to visualize CT scan data. I also chose not to model the lobes separately because they are not the primary concern for this project and can be added later using materials.

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Posted in anatomy, digital 2D/3D, my projects, techniques | Tagged: , , , , | 2 Comments »

Ear Prosthesis Part 1

Posted by Janet on January 29, 2008

ear-cast.jpgI’m taking a modeling class right now and our first project is a human ear prosthesis. It’s very exciting and I will be posting updates until it is done. This picture above shows the cast I made yesterday of a classmate’s ear. Later we’ll be sculpting the opposite ear and eventually making a prosthesis of that ear.

A lot of the materials we use are the same as those used for dental casting. We started by sealing an area outside the ear with boxing wax and stuffing some cotton down our partner’s ear canal. Very quickly we mixed and syringed alginate over the ear, covering everything. Since alginate remains soft and gel-like, some plaster was poured over the whole thing to help the mold hold its form. Once the mold was finished, I mixed some dental stone and poured it into the mold. While waiting for the stone to set, I got a cast of my own ear made by my partner.

Although the process sounds fairly straightforward, it was seven hours before I went home. Part of it was waiting time, and part of it was the time it took to clean up all the imperfections. But at the end of the day I got to take home this piece of ear to show everybody and that makes it all worthwhile.

Posted in my projects, prosthesis | Tagged: , , , , | 1 Comment »