KeckCAVES On Mars, pt. Oh-I-lost-count

Last weekend, we had yet another professional film crew visiting us to shoot video about our involvement in NASA’s still on-going Mars Science Laboratory (MSL, aka Curiosity rover) mission. This time, they were here to film parts of an upcoming 90-minute special about Mars exploration for the National Geographic TV channel. Like last time, the “star” of the show was Dawn Sumner, faculty in the UC Davis Department of Earth and Planetary Sciences, one of the founding members of KeckCAVES, and member of the MSL science team.

Unlike last time, we did not film in the KeckCAVES facility itself (due to the demise of our CAVE), but in the UC Davis ModLab. ModLab is part of an entirely different unit — UC Davis’s Digital Humanities initiative — but we are working closely with them on VR development, they have a nice VR environment consisting of two HTC Vive headsets and a large 4.2m x 2.4m screen with a ceiling-mounted ultra-short throw projector (see Figure 1), their VR hardware is running our VR software, and they were kind enough to let us use their space.

Figure 1: Preparation for filming in UC Davis’s ModLab, showing its 4.2m x 2.4m front-projected screen and ceiling-mounted ultra-short throw projector, and two Lighthouse base stations.

The fundamental idea here was to use several 3D models, created or reconstructed from real data sent back either by satellites orbiting Mars or by the Curiosity rover itself, as backdrops to let Dawn talk about the goals and results of the MSL mission, and her personal involvement in it. Figure 1 shows a backdrop in the real sense of the word, i.e., a 2D picture (a photo taken by Curiosity’s mast camera) with someone standing in front of it, but that was not the idea here (we didn’t end up using that photo). Instead, Dawn was talking while wearing a VR headset and interacting with the 3D models she was talking about, with a secondary view of the virtual world, from the point of view of the film camera, shown on the big screen behind her. More on that later. Continue reading

KeckCAVES on Mars

You might have heard that NASA has a new rover on Mars. What you might not know is that KeckCAVES is quite involved with that mission. One of KeckCAVES’ core scientists, Dawn Sumner, is a member of the Curiosity Science Team. Dawn talks about her experiences as tactical long term planner for the rover’s science mission, and co-investigator on several of the rover’s cameras, on her blog, Dawn on Mars.

Immersive 3D visualization has been used at several stages of mission planning and preparation, including selection of the rover’s landing site. Crusta, the virtual globe software developed by KeckCAVES, was used to create a high-resolution global topography model of Mars, merging the best-quality data available for the entire planet and each of the originally proposed landing sites. Crusta’s ability to run in an immersive 3D display environment such as KeckCAVES’ CAVE, allowing users to virtually walk on the surface of Mars at 1:1 (or any other) scale, and to create maps by drawing directly on the 3D surface, was important in weighing the relative merits of the four proposed sites from engineering and scientific viewpoints.

Dawn made the following video after Gale Crater, her preferred landing site, had been selected for the mission to illustrate her rationale. The video is stereoscopic and can be viewed using red/blue anaglyphic glasses or several other stereo viewing methods:

We filmed this video entirely virtually. Dawn is working with Crusta on a low-cost immersive 3D environment based on a 3D TV, which means she perceived Crusta’s Mars model as a tangible 3D object and was able to interact with it via natural gestures using an optically-tracked Nintendo Wii controller as input device, and point out features of interest on the surface using her fingers. Dawn herself was filmed by two Kinect 3D video cameras, and the combination of virtual Mars and virtual Dawn was rendered into a stereo movie file in real-time while she was working with the software.

Now that Curiosity is on Mars, we are planning to continue using Crusta to visualize and evaluate its progress, and we hope that Crusta will soon help planning and executing the rover’s journey up Mt. Sharp (NASA have their own 3D path planning software, but we believe Crusta has useful complementary features).

Furthermore, as the rover progresses, it will send high-resolution stereo images from its mast-mounted navigation camera. Several KeckCAVES developers are working on software to convert these stereo images into ultra-high resolution digital terrain models, and to register these to, and integrate them with, Crusta’s existing Mars topography model as they become available.

We already tried this process with stereo imagery from the previous two Mars rovers, Spirit and Opportunity. We took the highest-resolution orbital topography data available, collected by the HiRISE camera, and merged it with the rover data, which is approximately 1000 times more dense. The following figure shows the result (click to embiggen):

The white arrow in panel A shows the location of the rover’s high-resolution data patch shown in panels B and C. In panel C, a stratum of rock — identified by its different color — was selected, and a plane was fit to the selected points (highlighted in green) to measure the stratum’s bedding angle.

The above images were created with LiDAR Viewer, another KeckCAVES software package. LiDAR Viewer is used to visually analyze very large 3D point clouds, such as those resulting from laser scanning surveys, or, in this case, orbital and terrestrial stereo imagery.

The terrain data we expect from Curiosity’s stereo cameras will be even higher resolution than that. The end result will be an integrated global Martian topography model with local patches down to millimeter resolution, allowing a scientist in the CAVE to virtually pick up individual pebbles.