Fiscal Year:
2010
Title:
SAFE-P: System for Assurance of Flight Executable Procedures
Agency:
NASA
Contract:
NNX10CA17C
Award Amount:
$599,924.00
Abstract:
NASA operates manned spacecraft according to rigorously-defined standard
operating procedures. Unfortunately, operating procedures are often written in
different languages. For example, Orion will use automatic procedures written
in SCL, the Spacecraft Command Language, while backup manual procedures may be
developed in PRL, the Procedure Representation Language. However, procedures
developed in different languages may diverge, so that the backup PRL procedures
do not operate in the same way as the SCL procedures. This could lead to
unintended effects that may range from simply unexpected to inefficient or even
catastrophic.
We propose to develop the SAFE-P tool, which will use formal model-checking
methods to prove that PRL and SCL procedures have the same underlying execution
semantics. Our Phase 1 effort validated the effectiveness of our approach;
Phase 2 will completely automate the model checking process and integrate with
the Procedure Integrated Development Environment (PRIDE). SAFE-P will thus
allow procedure authors to easily compare procedures as they are being
developed. When differences are found by SAFE-P, they will be highlighted
immediately in the PRIDE interface, allowing the operators to either fix
problems or annotate the respective procedures to explain the differences.
Using SAFE-P, NASA personnel will rapidly and confidently verify that if an
automatic SCL program cannot be executed, a backup manual procedure in PRL will
be equivalent and safe. Furthermore, as automatic translators are developed to
transform procedures in one language into another NASA-relevant language (e.g.,
Tietronix's current effort to translate PRL into SCL), the SAFE-P tool will
provide a critical validation mechanism to double-check the correctness of the
translation and highlight areas where the translator makes mistakes (or
deliberate approximations that yield different behavior).
Small Business Information at Submission:
SIFT, LLC
211 N. First Street, Suite 300 Minneapolis, MN 55401
EIN/Tax ID:
411929753
DUNS:
N/A
Number of Employees:
Woman-Owned:
No
Minority-Owned:
No
HUBZone-Owned:
No