DIY Planetarium

Blender Render

2010-01-12T00:24:00.001-08:00

Hello Planetarium Community:

It has been quite some time since I've posted on this blog. In that 'quite some amount of time' however I have been very busy.

I have been working on three projects.
-1: 27 Core Blender Render Farm
-2: 15 minute 3k fulldome production on the 4-H youth program

-3: A Java Application that creates gore dome construction patterns based on user input.

I will begin with the Render Farm. Without sufficient computing power, 3D animation will take forever. Forever is not a word I like to use when talking about render time. In July, I built a plywood box that houses eight computers on server-style slide mount shelves. The front is open as is the back to allow air to flow over through the case for optimum cooling. I modeled this machine after server type supercomputing clusters in slide mounts. Currently the system is running a render client called LOKI Render that manages all computers and renders content to one directory. Below is a picture of this machine codenamed AMOS.

Part II. The Renders.

I used Blender, a 3D animation software to create original planetarium fulldome content for a fundraising GALA at the Denver Museum of Nature and Science. Thanks to Dan Neafus and the Museum's public outreach and academic projects mission, I was able to show my content at the GALA. The production showcases the past and present of the 8 million body strong youth organization, 4-H. It also delves into the potential of fulldome education and it's powerful inspiring ability. Below are snapshots from my production 4-H Evolving.

Lightning

Dancing Figures (Particle System)

Speaking about Land Grant University system

Current Projects (Video and Image Panels)

Corn Club Projects

Canning Club Projects

Lightning Photography Project

Model Rocketry Project (Animated Video Panes)

Environmental 4-H Projects (Green Movement)

Dynamic Atmosphere (corrects with planetary rotation)

Animal Science Project

(Animated Blood Vessel Fly-Through)

4-H. One Million New Scientists. One Million New Ideas.

Nuclear Generation or Renewable Wind Energy?

Which energy source will win the betamax-vhs battle?

I almost forgot, planetariums can be FUN

Here is an image from the bubble gum drop:

The audience is placed in a glass dome, and thousands

of giant bubble gum pieces fall on the glass dome above

their head. This part of the show was to demonstrate

the entertainment value of fulldome productions.

Closing Scenes

Recap of 4-H with Logo (Animated Spotlights)

Ocean Waves (Dynamic Waves)

GORE SECTION JAVA CALCULATOR:

The Java Application I have been developing is codenamed GoreCalculator. It is a branch of my idea 'that all people should be able to create cheap, high quality planetarium domes' in a fast easy to produce way. As all enthusiast's and mathematicians know, a common planetarium dome is made from 'triangular' shaped pieces called gores.

The gore sections can only be as wide as the material you are working with. My program asks the user for the following input:

Dome Diameter
Material Width
Number of lateral divisions on each gore

My program also has the option to add a seam allowance. Depending on the construction method, the gores can be taped directly together (edge to edge) or melted together by a seam.

I have working JAVA code for all interested. As of now the program is strictly command line based but I am working on a GUI version. If you have any questions about my recent developments, please send me a message.

Maiden Voyage of my mirror dome system:

Star show and fulldome slideshow at a stargazing party.

Walden, CO

DIY Planetarium Update

2009-07-01T21:57:00.000-07:00

Hello again, it has been several months since my first posting and I am updating the blog with photos of my dome inflated. My name is Adam Goss and I am working on developing portable, inexpensive high quality planetariums for the every day astronomer, guru or techie alike. The photos below are from a week long summer camp I worked at called Camp Invention. There were 60 kids/day coming through my dome, aging kindergarten through 6th grade. I showed them IMAX movies from the Amazon, Ocean, Volcanoes and even some fun roller coaster rides. The kids had a blast. I also gave the usual star show complete with the Mirrordome/Stellarium combination.

Side of dome, tilted at a 23 degree angle rendering Earth

Front of Dome rendering Earth in Celestia

Inside the dome - flying through galaxies.
More photos and information from June 28th 4-H Summer Outreach Program coming soon.

DIY Planetarium No. 1

2009-03-18T23:56:00.000-07:00

DIY PLANETARIUM No. 1

Hello, my name is Adam Goss and I've spent these past few days constructing a 5 meter diameter Gore Dome inflatable Planetarium out of a thin, lightweight table cloth plastic. I've always enjoyed working with planetariums and have recently taken them up as a hobby. As I'm also a member of the Yahoo Groups Small Planetarium blog I thought it would be fitting to create a blog on my project, documenting the steps for anyone who would like to replicate them. There are several methods for building a planetarium, but some methods are obviously better than others. A typical amateur approach to planetarium construction is the geodesic dome, constructed of cardboard pentagons. Although this is a perfectly valid approach, it does a poor job of representing a hemisphere as there are many flat sides. A better approach to planetarium design is a pattern called Gore Domes. Although there is little literature on Gore Domes, the design is used in most planetariums around the world. I am a native of Colorado and live close to the Denver Museum of Nature and Science who recently renovated their planetarium. Their new all digital Gates Planetarium is constructed from a thin sheets of aluminum using the Gore Dome design. Gore domes are unique in that they take flat objects and stitch them together to create a three dimensional dome. The dome itself is constructed from many bulging triangular shaped pieces called 'Gores.' A good representation of this that many of us have done is the elementary orange peel trick; trying to make a 3D object flat (the opposite of what we want to do).

The Gores in this project will look almost exactly like these below:

MATERIALS:

The following materials will be needed when constructing this planetarium:

Marker
Pen
Scissors
Ruler (Metric)
40'' wide roll of white tablecloth plastic
Masking tape (1.25'' wide)
Duct Tape
Blue Painters Tape
Calculator

STEP 1:
By using the pattern provided by the July 1973 Popular Science Article (here) on Gore Domes, scale all measurements to fit the diameter of the dome being built. The diameter of the dome in the article is 25 Feet, so in order to make my dome (5 meters), I had to multiply all of the dimensions by a scale factor of 0.656167979. This multiplier scaled all dimensions down to a 5 meter diameter, but kept units in English measurement. This is fine if you're comfortable with English units, however I find metric units to be easier to work with on a project like this. I simply set up an excel spreadsheet to calculate the proper dimensions at each height level. A link to a PDF of my calculations can be found here.

STEP2:
Setting up a solid template for cutting out the Gores is crucial when aiming towards a 'perfect' dome. After calculating the dimensions of my Gores, I found it easy to make a template out of tape on the floor. This made cutting and fabricating the sections easy. I laid out plastic over the pattern, put a few books on the top to hold things in place and just ran scissors around the edge for a nice clean cut.

STEP3:
Taping together the Gores is tedious work. If you're taping on the ground (easiest) I would recommend a pair of knee pads to combat the hours of brutality they would otherwise endure (I learned the hard way). Taping the gores together can be done on a table, but is difficult because they keep sliding around. I haven't found a cut and dried method for taping together the sections, but small strips at a time seem to work well as the curvature of the gores is always changing. In my procedure, I started with the top of the gores and worked down to the bottom. On the last section, I brought around the ends and taped them together. After the main body of the dome has been taped together, the pieces can be spread out to reveal the circle left in the top of the dome. Simply cut out a circle to fit in the top (see dimensions PDF) and tape it in.

STEP 4:
The final step of the planetarium process is the fan/inflation procedure. For my setup, I created a pipe that fitted onto a common everyday house fan with the excess plastic. I taped one end to the fan and the other to the ground. Taping the bottom of the output pipe to the ground and narrowing the top (taping parts of the top edges to the ground) creates a very steady non-turbulent airflow ideal for planetariums. After I had the inflation system in place, I laid out the planetarium on the floor so that the inflation pipe was sticking under one of the edges of the dome. The edges were held down with soup cans, but I recommend anything from tape to sandbags (the smaller the footprint the better).

STEP 5:
Enjoy...

My basement was too small for this dome to fully inflate. When I head back up to CSU next week I will be testing this dome in full capacity in one of the ballrooms, complete with a mirrordome projection system. Until then, questions and comments are welcome. I will keep this blog updated as this project progresses. My email is adamthomasgoss@gmail.com. Thanks for reading and happy building!