The
embedded computer system
A computer is a machine that can be programmed to carry out sequences of arithmetic or logical operations ( computation) automatically. Modern digital electronic computers can perform generic sets of operations known as programs. These prog ...
s on board the
Mars rover
A Mars rover is a motor vehicle designed to travel on the surface of Mars. Rovers have several advantages over stationary landers: they examine more territory, they can be directed to interesting features, they can place themselves in sunny p ...
s sent by
NASA
The National Aeronautics and Space Administration (NASA ) is an independent agency of the US federal government responsible for the civil space program, aeronautics research, and space research.
NASA was established in 1958, succeedi ...
must withstand the high radiation levels and large temperature changes in space. For this reason their computational resources are limited compared to systems commonly used on Earth.
[Max Bajracharya, Mark W. Maimone, Daniel Helmick (2008) (]Jet Propulsion Laboratory
The Jet Propulsion Laboratory (JPL) is a federally funded research and development center and NASA field center in the City of La Cañada Flintridge, California, United States.
Founded in the 1930s by Caltech researchers, JPL is owned by NASA ...
and California Institute of Technology
The California Institute of Technology (branded as Caltech or CIT)The university itself only spells its short form as "Caltech"; the institution considers other spellings such a"Cal Tech" and "CalTech" incorrect. The institute is also occasional ...
); ''Autonomy for Mars rovers: past, present, and future''; published in: '' Computer'', a journal of the IEEE
The Institute of Electrical and Electronics Engineers (IEEE) is a 501(c)(3) professional association for electronic engineering and electrical engineering (and associated disciplines) with its corporate office in New York City and its operati ...
Computer Society, December 2008, Volume 41, Number 12, page 45, .
In operation
Direct
teleoperation of a Mars rover is impractical, since the round trip communication time between Earth and Mars ranges from 8 to 42 minutes and the
Deep Space Network system is only available a few times during each Martian day (
sol
Sol or SOL may refer to:
Astronomy
* The Sun
Currency
* SOL Project, a currency project in France
* French sol, or sou
* Argentine sol
* Bolivian sol, the currency of Bolivia from 1827 to 1864
* Peruvian sol, introduced in 1991
* Peruvian sol ( ...
).
Therefore, a rover command team plans, then sends, a sol of operational commands to the rover at one time.
A rover uses
autonomy software
Software is a set of computer programs and associated software documentation, documentation and data (computing), data. This is in contrast to Computer hardware, hardware, from which the system is built and which actually performs the work.
...
to make decisions based on observations from its sensors.
Each pair of images for stereo the ''
Sojourner'' rover could generate 20 navigation 3D points (with the initial software version the craft landed with). The
MER rovers can generate 15,000 (nominal) to 40,000 (survey mode) 3D points.
Performance comparisons
With the exception of ''
Curiosity'' and ''
Perseverance'', each Mars rover has only one on-board computer. Both ''Curiosity'' and ''Perseverance'' have two identical computers for redundancy. ''Curiosity'' is, as of February 2013, operating on its redundant computer, while its primary computer is being investigated for the reasons why it started to fail.
Mars Rovers
See also
*
Radiation hardening
References
External links
The CPUs of Spacecraft Computers in Space
{{DEFAULTSORT:Comparison of Embedded Computer Systems on Board The Mars Rovers
Space technology
Exploration of Mars
Computing comparisons