Space Tech: Indepth Look at Mars Curiosity Computer Systems
NASA’s Mars Science Laboratory (MSL) spacecraft — called Curiosity — launched aboard a United Launch Alliance Atlas V rocket November 26, 2011. It traveled for nine months until it reached its destination: The Red Planet. This trip, and the ongoing scientific experiments, were all made possible by the hard and complex work of programmers.
Curiosity “is powered by a RAD750, a single-board computer (motherboard, RAM, ROM, and CPU) produced by BAE. The RAD750 has been on the market for more than 10 years, and it’s currently one of the most popular on-board computers for spacecraft. In Curiosity’s case, the CPU is a PowerPC 750 (PowerPC G3 in Mac nomenclature) clocked at around 200MHz — which might seem slow, but it’s still hundreds of times faster than, say, the Apollo Guidance Computer used in the first Moon landings.”, according to ExtremeTech.com
“On the software side of things, NASA again stuck to tried-and-tested solutions, opting for the 27-year-old VxWorks operating system. VxWorks, developed by Wind River Systems (which was acquired by Intel), is a real-time operating system used in a huge number of embedded systems. The previous Mars rovers (Sojourner, Spirit, Opportunity), Mars Reconnaissance Orbiter, and the SpaceX Dragon spacecraft all use VxWorks.”
The image to the right is from NASA, showing the various scientific instruments built into the rover. “A suite of instruments named Sample Analysis at Mars analyzes samples of
material collected and delivered by the rover’s arm, plus atmospheric samples. It
includes a gas chromatograph, a mass spectrometer and a tunable laser spectrometer with combined capabilities to identify a wide range of organic (carboncontaining) compounds and determine the ratios of different isotopes of key elements.” Here is a link that includes NASA’s description of the laboratory equipment on board.
The Trip to Mars
Curiosity launched on November 26, 2011 from Cape Canaveral Air Force Station in Florida and landed on the floor of Gale Crater on Mars on August 6, 2012.
Even during the trip to Mars, Curiosity was gathering data and sending it back to Earth. “Unlike previous Mars rovers, Curiosity is equipped with an instrument that measures space radiation.”, NASA reports. “The Radiation Assessment Detector, nicknamed “RAD,” counts cosmic rays, neutrons, protons and other particles over a wide range of biologically-interesting energies. RADs prime mission is to investigate the radiation environment on the surface of Mars, but NASA turned it on during the cruise phase so that it could sense radiation en route to Mars as well.”
And how did this 10-foot-long, 1-ton rover gently land on the Martian surface without breaking all these delicate instruments? “During the three minutes before touchdown, the spacecraft slowed its descent with a parachute, then used retrorockets mounted around the rim of an upper stage. In the final seconds, the upper stage acted as a sky crane, lowering the upright rover on a tether to the surface.”
What can it do on Mars?
Powered by 10.6 pounds of plutonium dioxide, this nuclear-powered rover may travel up to a couple dozen miles on Mars throughout its life. It has has 17 2-megapixel cameras on board and will be constantly sending photos back to Earth. It also has drills and lasers powerful enough to drill into rocks. It has claws, too, to lift up samples to place into its two on board labs.
The results of all these lab tests, images taken from its cameras, as well as log files indicating what it did and any error messages are sent back to Earth. “Curiosity can either communicate directly with Earth’s Deep Space Network (DSN) antenna via an X band (8GHz) link, or it can use a UHF (300MHz-3GHz) transmitter to relay signals through Mars Odyssey and Mars Reconnaissance Orbiter, which orbit a few hundred miles above Curiosity. Because it’s a lot cheaper for Curiosity to use UHF, and because the Mars Reconnaissance Orbiter has a very-high-speed 6Mbps X band antenna, relaying will be Curiosity’s main way of sending data back to Earth.”. says ExtremeTech.com
Back on Earth
With all this data streaming back to Earth from this technologically advanced rover, NASA developed some sophisticated reporting systems to display and disseminate data.
“The project utilizes a new MySQL-based system to process the large amount of raw and complex data that comes in from Curiosity. Called the Mission Data Processing and Control System (MPCS), it interfaces to NASA’s Deep Space Network and processes data from the Mars Reconnaissance Orbiter and other in-orbit systems. MPCS produces a tailored view of the data that is used by other flight operations teams, such as information on the power system”, reports Information Week.
If Curiosity, with all its tools, is able to survive the harsh conditions of Mars like its cousins Spirit and Opportunity, we are in store for many years of exciting revelations from this technological marvel.
Curiosity’s official website is http://www.nasa.gov/mission_pages/msl/index.html