Space Station Team Undertakes 'EPIC' Event

Anyone who has ever been involved in a computer upgrade knows that they can be complicated, and that you have to take your time, be careful, and go step-by-step if you want to be successful.That’s exactly what the Expedition 30 crew and International Space Station team in Mission Control are doing as they install a set of Enhanced Processor and Integrated Communications (EPIC) computer cards in the seven primary computers on the station.EPIC is the shorthand name the team is using to describe this upgrade of the main processor cards. The seven computers, which are formally called Multiplexer/Demultiplexers, are used for Guidance, Navigation, & Control; Command and Control; and Payload, or experiment, control. The new cards have faster processors, more memory, and an Ethernet connection for data output. Astronauts use laptop computers to control station systems through these main computers.In addition to the hardware upgrade, the crew and ground teams are also updating the station’s software to what is known as Command and Control Software Revision 10 (X2 R10).The upgrade is enabling the operation of more controlled experiments at one time, which will help maximize the research capacity of the multinational laboratory as it continues to operate until at least 2020. Under the old hardware and software setup, approximately 12 different experiments could be operated at one time. The upgrade will support more than 25 simultaneous experiments, which meets the ground team’s support capability given existing staffing levels.The upgrade also is needed to support operations for upcoming commercial visiting vehicles, such as the SpaceX resupply ship Dragon that is scheduled to launch Feb. 7. The upgrade affects communications between the station and visiting vehicles, including robotic arm and Common Berthing Mechanism operations on the ports that the vehicles will be connected to when they arrive, allowing the crew to transfer their contents inside.The EPIC process included an additional level of complexity, because last fall NASA discovered problems on several EPIC cards on Earth. As a result, the crew had to go through an additional step of testing each card before installation. The good news: all of the suspect cards passed.The EPIC upgrade is occurring in two phases, with Expedition 30 Commander Dan Burbank and Flight Engineer Don Pettit doing the majority of the work on orbit.The first involves upgrading the three Command and Control and the two Guidance, Navigation and Control computers. This phase began during the last week of December and should be completed by January 7. So far, all installed cards are performing well.In the second phase, the team will upgrade the two Payload computers and add Ethernet support for the Command and Control and Payload computers. This Ethernet support will provide a faster path for data being downlinked to Earth and will be completed before Expedition 30 ends.