Russian computers partially working, cosmonauts finishing repair on Space Station

William Atkins
Friday, 15 June 2007 01:34

Science - Space

In what is considered an unbelievable situation in space, all of the computers for the Russian side of the Space Station went down on Wednesday, June 13, 2007. By the next day, Thursday, the Russian cosmonauts have partially re-established communications.

The Russian computers control the orientation of the International Space Station within its orbit about the Earth by thrusting small jets. However, with the computers down, the Space Shuttle Atlantis is performing this task.

In addition, the Russian computers also control environmental factors, such as water supply, onboard the Space Station. Of special concern is the ability to provide oxygen to breath for the astronauts and cosmonauts onboard. Without the flow of oxygen being controlled by the computers, a reserve of about 56 days is set aside for emergencies such as what is possible here.

NASA and Roskosmos (the Russian Federal Space Agency) officials did not know what caused the computer problem.

NASA officials are indicating that the problem could reside within the electrical system and not with the computer software. NASA engineers working on the problem have initially theorized that the large solar array, which was just installed, may be to blame for the problem. They conjecture that the  electromagnetic field created by the solar array may be causing disruptions within the electronics onboard the Station.

However, it is still too early to make a definite statement as to the true problem plaguing the people onboard the orbiting laboratory. As of Thursday, June 14, 2007, the cosmonauts are stating that the computer system has turned on and off at various times while they are troubleshooting the problem.

The Russian computer system onboard the International Space Station is called the DMS-R (Data Management System-Russia) system. DMS-R consists of a set of onboard computers that provide for the overall control of the Russian section (Zvezda [“star”] Service Module) of the Space Station.

Some of the duties performed by the DMS-R computers are guidance, navigation, and control; mission management, failure management and recovery; exchange of data and information with other parts of the Station; and time distribution and synchronization for onboard system;

The computer components of the system are two Fault Tolerant Computers (FTCs, one Control Computer and one Terminal Computer) for attitude control and guidance; and two Control Post Computers (CPCs) for command and control by the crew for experiments.

The CPCs can also be used for the future European Robotic Arm (ERA) as well as the docking of supply vehicles.

The hardware for the DMS-R system was developed by the German company Astrium (as a joint venture of the European Aeronautic Defense and Space Company [EADS] and BAe Systems), and the DMS-R software (with an European Space Agency’s ground system) was developed by the Russian contractor RSC Energia.

The DMS-R system has been in operation aboard the Space Station since July 2000.