Using a Virtual Environment Simulator to Test
Dynamically Executing Flight Software
Triakis has received a grant from the NASA Independent Verification and Validation (IV&V) Facility for a case study to evaluate the viability of testing NASA flight softeware executing in a simulation of the hardware and environment in which it is designed to operate. Leading this study, Triakis is conducting the effort with support from the Information Research Corporation (IRC), a West Virginia-based small business that currently conducts IV&V of embedded systems and software under contract for NASA.
In this case study, are simulating the STEREO spacecraft hardware and orbital environment with sufficient fidelity to run the unmodified executable flight software. Using this pure virtual environment we will develop a full suite of nominal and off-nominal tests to verify that the software has correctly implemented the system and software design requirements. Software path coverage will be monitored and all unexercised code will be documented. Further, we will "stress test" the system to evaluate its robustness by varying instruction execution speed, propagation delays, data skew and other parameters readily adjustable in a virtual environment.
This one year study will help the NASA IV&V Facility determine the extent to which new system and software faults may be uncovered through dynamic test of the flight software, and consequently the extent to which the value of IV&V may be enhanced.
