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Science, Art and Engineering Collide

My day job is to analyze geospatial data on the computer. The data, usually from cameras looking down at Earth and Mars, is really interesting to look at: lava flows, sand dunes, river channels, among many other things. It’s value is primarily to science, but the world’s patterns and abstractness have artistic value. Many people recognize this, and some celebrate this by contributing to The Art of Planetary Science Exhibition in Tucson, AZ. There are many submissions this year from almost a hundred artists, and I’m happy to be one of those contributors this year in 2018.

I have been fascinated by 3D printing and carving. As interested as I am in the products these machines produce, I’m interested in the process of making things myself and building the machines themselves. Most of these consumer-grade machines all accomplish their goal of manufacturing using  computer numerical control (CNC), driving an extruder (for 3D printing, usually plastic, and is an additive process) or a milling bit (in the case of carving). CNC milling has been around a lot longer than 3D printing and is generally not constrained by a “build volume” in the same way as a printer. For my hobby as a “Maker,” I decided to go with a carving machine before a 3D printer.

I started with a basic Shapeoko2 in 2014, and then upgraded to a nearly complete 1 meter x 1 meter XCarve. (I did a fair amount of customization and stepwise upgrades.) My first goal was to cut out parts for custom aerial camera jigs that I could mount to kites and unmanned aerial systems (UAS), aka, drones. I use the camera images I’ve taken of geological field sites (hundreds to thousands of the land surface) and process them into digital terrain models (DTMs). I plan to create scaled models of the data in materials like wood, foam and MDF using my CNC. Satellite images of Mars are also collected for the same purpose. The HiRISE instrument collects stereo pairs, and these image pairs are processed into DTMs as well.

My submission this year is a carved HiRISE DTM, and is my first completed 3D carve of topography. Take a moment here and think about everything that went into this 20 x 70 cm piece. Scientists buildt and designed a sophisticated camera that could orbit another planet (Mars) and take pictures of the planet surface from different angles. Those pictures are later lined up exactly right to calculate the geometry of the planet surface. That took years. Then I came along, downloaded the data and manipulated and scaled it to fit the specifications of my CNC machine. The machine was designed by some fun and nerdy engineers. (That probably took a long time.) I bought one; put it together; fiddled with and customized it; and learned everything I needed to know about milling from a large community of people that share their knowledge on forums and in YouTube videos. Meanwhile, I built my shop around this machine, complete with dust collection. That took me about 3.5 years to be where I am now. The 3D data were then used to create a text file (gcode) using CAM software listing all of the movements of the milling bit for the machine to execute. These data were streamed by a computer twice (once for roughing, once for finishing) to transfer the shape of Mars onto a $15 piece of MDF. I had other plans for completing the finish of this project, but time did not allow. I was lucky to even finish the project on time due to the fact that static electricity, generated by the dust flowing off and away from the carve, was shorting out the electronics running my machine. (Thanks again to all the people that shared their experience on the web in dealing with engineering problems and how they solved them.)

I’m pleased with the way it turned out, and I’m happy to put my piece among all of the talented artists that contributed to this year’s exhibition. If you live in the Tucson area, come check it out.

Description of Piece: A place on Mars in miniature Fissure and Channel Southeast of Olympus Mons. Carved by a homemade computer numerical control (CNC) milling machine; surface tone painted by hand. Image data were provided by The High Resolution Imaging Science Experiment (HiRISE) camera in orbit around Mars, which were processed into a digital terrain model by the HiRISE Science Team.

Iceland Field Campaign 2016

I have to admit: Flying an unmanned aerial vehicle (UAV) such as the Trimble UX5-HP is a lot easier than flying a kite over lava flows. We covered several square kilometers in no time with this bird! There were two location: the south of Iceland (the Laki lava flow) and in the north of Iceland (the Holuhraun lava flow). We worked with a great group of students in the field participating in the Keck Geology Consortium. They helped us run our mobile UAV airport! I’ll post more details about our field work and the student projects soon. For now, here are a few images of us doing our volcanological mapping. The data will result in orthoimage data at 1-4 cm per pixel, and digital terrain models at 10 cm per pixel!

Iceland Field Campaign 2015

Flying a kite for aerial photogrammetry was difficult because Iceland has relatively unpredictable weather, including the wind. I was able to make a couple of flights in the northern part of Iceland near the Holuhraun lava flow, which finished erupting just a few months before our arrival. Most of our mapping work during this summer of 2015 field campaign was accomplished using DJI Phantom 3 Professional unmanned aerial vehicles (UAVs). You can see more details here at this website, including publication. Much of this work is still underway.

University of Arizona Press Release

I worked on a project on lava flows in Hawaii with Dr. Christopher Hamilton. One of the goals was to study and understand the morphology of the December 1974 flow from Kilauea. A couple years prior, I had started a hobby of kite aerial photography (KAP). Because of the uncertainty around flying unmanned aerial vehicles (UAVs) in sensitive places, I was able to leverage my new hobby as a skill to collect over 10,000 kite aerial images of our study site. I used a computer vision technique called multiview stereophotogrammetry to build a digital terrain model at cm-scale spatial resolution for our research team. Read more in the excellent press release written by Daniel Stolte at University of Arizona.

UA Scientists Fly Kites in Hawaii to Study Mars

An outflow channel of the December 1974 lava flow on the big island of Hawaii.

University of Pittsburgh Press Release

Following our publication in the Journal of Geophysical Research, a few news outlets picked up the story and featured the work on their webpages. Check out the original press release HERE and the research article HERE. I particularly liked the take from AGU Blogosphere and Science Daily. Although apparent thermal inertia (ATI) is typically used for methods in planetary geology, it can still be a useful tool for Earth surface processes.

This time-series of data show how apparent thermal inertia (ATI), calculated from ASTER data, varies across a section of playa and dune surfaces in the White Sands Dune National Monument. High values shown here typically correspond to the wettest areas, where as low values are quite dry.