Automated Analysis of Shuttle Wiring Using SCAN

The integrity of the electrical wiring within the Space Shuttle is of critical importance. Proper operation of all computer controlled elements in the Shuttle and therefore, the safety of the crew is dependent upon it. And yet, our nation\u27s Space Shuttle is an extremely versatile and dynamically changing vehicle. It was designed from its inception to be readily adaptable to varying payload cargo requirements from mission to mission. On a typical mission, over 1000 electrical connectors must physically undergo demating and remating in order to prepare the Shuttle for the unique functions to be carried out on a particular flight. These disconnections are due to three primary requirements. First, unique payload wire harnesses are installed for .each flight for the attachment of the payloads scheduled for the mission. Second, in preparation for a mission some of the 2000 Line Replaceable Units (LRU) or black boxes must be removed, serviced and replaced. This action either corrects a problem that was observed during check-out at Kennedy Space Center or in flight, or is part of planned preventative maintenance procedures. Finally, wiring modifications are required within the Space Shuttle to incorporate approved critical changes of the flight systems to keep pace with the new roles required of the Shuttle. Thus there is an apparent dichotomy. On the one hand, the wiring configuration must be controlled and we would therefore like not to touch it. Yet on the other hand, some change cannot be avoided in order to accomplish the Shuttle\u27s mission in space