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NASA Mars Rover
The
Mission
Fascination with the planet Mars has grown over the centuries. The
discovery of canals by astronomers in the late 1800s, and the first views provided by the fly-by of the Mariner 4 spacecraft
in 1965, inspired a search for life on the Red Planet. Today, the search focuses on water. It is still considered possible
that life in some form exists in water on Mars, whether in underground springs or beneath thick ice caps. By learning more
about the history of water on Mars, scientists hope to replace myth with reality and answer some of the larger questions about
our universe.
NASAs 2004 mission to Mars deployed two golf cart sized rovers equipped with cameras and scientific
instruments for viewing and analyzing the surface. Mission scientists need a fail-safe way to plan the movements of the rovers,
ensure successful operation, and maximize knowledge gained. NASA scientists chose professional computer graphics technology
from NVIDIA Corporation to meet this need.
NASA is using NVIDIA Quadro® graphics solutions to reconstruct Martian
terrain from transmitted rover data in photorealistic virtual reality, allowing scientists to explore Mars in 3D as if they
were actually moving freely on the planets surface. This NVIDIA-powered environment serves as a precise visualization and
planning system for NASA scientists, allowing them to rehearse a variety of Mars rover scenarios, mapping out moves and experiments
by "flying" through highly realistic 3D reconstructions of the Martian surface, prior to directing the vehicle to undertake
actual tasks.
Dealing with Martian Data
Over the next
three months, NASA will receive terabytes of data from two Mars rovers. The first rover, named Spirit, successfully landed
in the Gusev Crater on January 4, 2004, three weeks ahead of the touch-down date for the second rover. The Gusev Crater was
selected because it appears to have been eroded long ago by flowing water.
The landing site for the second rover, Opportunity,
is half way around the planet in a region called the Meridiani Planum. This location is one of the smoothest, flattest places
on Mars and is of interest because the Mars Global Surveyor spacecraft found that it is rich in an iron oxide mineral, or
rust, which typically forms in association with water.
Spirit sends data to Earth generated from two pairs of hazard-identification
cameras mounted below the deck at the front and rear of the rover and from two other camera pairs that sit high on the mast
rising from the deck. These cameras include a high-resolution panoramic camera and a pair of lower resolution cameras for
navigation.
The cameras provide the views needed to navigate the rovers and collect scientific data about geological
and weather conditions. Rover panoramic cameras send digitally massive high-resolution 360-degree panoramas of the surface
as 1024x1024x16-bit images. A rover transmission may include hundreds of images.
3D Maps for Roving
NVIDIA
Quadro graphics help scientists determine rover activities without having to sift through massive amounts of photographic
data. NASA scientists use NVIDIA graphics to visualize high-resolution photographic imagery more than three times as detailed
as images sent from the Sojourner rover in 1997. Because the new rovers travel six to ten times farther than Sojourner, taking
approximately 6,000 to 10,000 more measurements per foot, the data visualized with NVIDIA graphics is transformed into a particularly
detailed, visually enhanced, 3D representation of the planets terrain.
Rover operations run continuously throughout a mission. One group
of NASA scientists focuses on the days rover operation, while another plans the following days activities by studying and
interacting with the NVIDIA-rendered photographic and measurement data taken from targetedbut as yet unexploredMartian terrain.
As terrain models are reconstructed with new image data, existing 3D map segments are merged into a master virtual environment,
which willupon mission completionrepresent the totality of the rovers movements.
Laurence Edwards, Ph.D., Mars team
lead for 3D visualization and surface reconstruction at NASA Ames Research Center explains, "NVIDIA technology allows NASA
to visualize the Martian terrain in photorealistic virtual reality, greatly enhancing scientists understanding of the environment
and streamlining analysis. With this capability, scientists step into a visually engaging model of the planets surface and
interactively study multiple perspectivesfront, back, side viewsof every object the rovers investigate to fully explore all
options for rover routes and experiments."
"With NVIDIA Quadro graphics driving Viz, the virtual reality software
we use for Mars missions, we can also model the lighting and surface conditions expected to be present on Mars when an experiment
will be conducted," said Edwards. "If a rock will cast a shadow, obscuring a feature of interest, scientists on the ground
will know about this effect in advance and be able to plan around it. These NVIDIA-enabled capabilities allow NASA scientists
to conceptualize a variety of scenarios and map out rover moves and activities prior to directing the rover to undertake actual
tasks."
Advanced Visualization in PC Workstations
"NVIDIA technology has been key to meeting our evolving visualization
needs for Mars missions. The incredible performance, precision, and shadow mapping capabilities of NVIDIA Quadro solutions
enables NASA to use standard PC workstations to visualize reconstructions of the Martian surface in great detail. NVIDIA Quadro
boards, in individual systems and in clusters, allow us to construct 3D maps of the Martian terrain within a photorealistic
virtual reality space that greatly enhances scientists understanding of the remote environment and streamlines the process
of analysis," said Laurence Edwards.
Most scientists spend their time looking at terrain models using typical NASA
science operations workstations armed with NVIDIA Quadro FX 2000 graphics. According to Edwards, "This NVIDIA-powered solution
handles a good-sized portion of the overall terrain model and makes data access extremely cost-effective. For the highest
resolution, 3D terrain models with wide 360-degree views of the surface, we use NVIDIA Quadro FX 3000s. We also plan to cluster
a number of PC workstations armed with NVIDIA Quadro FX 3000Gs. Such a system will surpass the power of expensive supercomputers
and bring high-end visualization to a larger number of scientists."
According to Jeff Brown, general manager of workstation
product management at NVIDIA, NASA migrated Viz from supercomputer to PC-based workstations powered by NVIDIA Quadro graphics
for reasons such as:
- Performance:
A previous-generation NVIDIA Quadro graphics board
in a PC workstation displayed images 33% faster than the expensive, proprietary incumbent system.
- Superior Shadowing:
Allows Viz to optimally handle real-time, interactive
shadow simulation to predict sun/shade situations for experiments affected by light levels.
- Clustering:
The ability to link multiple NVIDIA Quadro FX 3000G
solutions allows Viz to run at or better than supercomputer performance levels at about one-tenth the cost.
- Greater Application Accessibility:
The full range of NVIDIA professional
graphics solutions, from the entry-level NVIDIA Quadro FX 500 to the high-end NVIDIA Quadro FX 3000G, available in industry-standard
PC workstations, makes NASAs Viz virtual reality software accessible from virtually any desktop.
Visualizing Future Mars Missions
The NASA Ames
3D Visualization and Surface Reconstruction team constantly evaluates graphics technology. They are committed to keeping Viz
on the leading edge and to ensuring that the scientific and communication requirements of upcoming missions are met. "We continually
investigate advanced concepts for rover operator interfaces and science operations interfaces," says Edwards. "Our group is
charged with bringing the latest technologies to the user interface portion of missions, and NVIDIA gives us several opportunities
for future enhancements. We plan to demonstrate a large, wrap-around user interface using a cluster of NVIDIA Quadro FX 3000G
graphics solutions to immerse scientists in a computer-generated display of the planets surface. We can see a point in the
future where researchers would sit in such a display and program rover movements and experiments using simple touch-screen
or voice commands."
Sharing Knowledge
By converting the data collected from cameras and scientific instruments
on the rovers into knowledge through visualization, NVIDIA graphics technology helps NASA share the knowledge gained from
Mars rover missions with the world. Scientists worldwide can access and study the largest and most topographically accurate
3D models ever constructed during remote space exploration. With the routine posting of NVIDIA-generated images on the Web,
the public can also virtually participate in NASAs search for life on Mars.
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