Testing Concepts for Human-Machine Teaming on Next-Generation Spacecraft
Shuttle crews are saddled with outdated cockpit interfaces and legacy software systems that impair their ability to diagnose and respond to time-critical systems malfunctions. The onboard fault-management software is largely confined to a caution and warning system that does little more than generate auditory alarms and written fault messages in response to out-of-limits sensor readings. Recently, NASA has developed fully automated fault management systems for unmanned spacecraft that do everything from recognizing sensor failures to diagnosing malfunctions to automatically selecting and executing fault isolation and recovery procedures. On next-generation crewed spacecraft, these systems could be harnessed to evolve the traditional caution and warning system into a fault management support system that assists the crew with virtually all fault-related operations.
A human factors evaluation of an advanced fault management concept for next-generation spacecraft was completed recently in NASA's Intelligent Spacecraft Interface Systems (ISIS) simulator. The concept included a caution and warning system with automated proximal (root) cause determination capabilities. The results of the evaluation illustrated the performance benefits that can be expected to accompany operational concepts that feature extensive human-computer interaction and automated assistance.
The figure illustrates the appearance of the primary crew interface with the advanced caution and warning system after a malfunction in a simulated battery-based electrical power system. The caution and warning system has automatically diagnosed the problem as a battery failure. The system then automatically organizes the information about the failure to direct the operator's attention to the "root-cause" of the problem, such as highlighting the fault message associated with the root cause ("battery B volts low") in the "root-cause list" box. If the user agrees with the automated assessment, he or she selects the corresponding fault message directly, which brings up the appropriate list of fault isolation and recovery procedures in the electronic procedure viewer on the right.
