System Mimics an Avionic Multiplexer/Demultiplexer

The multiplexer/ demultiplexer (MDM) emulator is the first virtual machine that can emulate an avionic computer. New flight software can be easily “dropped in,” increasing operational flexibility. The MDM makes it possible to perform integration more quickly, reducing the need for additional hardware. The MDM emulator will be used extensively in the Space Station Training Facility (SSTF), where teams of astronauts and ground controllers will be trained in operation and utilization of the station — the first use of virtual-machine techniques for training of this type. In addition to being a major advance in virtual machines, the MDM emulator is economical: Although the cost of its hardware is estimated at $4 M (an estimate, as of year 2001, that includes the cost of development and testing), it has been estimated that the MDM emulator will save $12 M in labor costs.