Crown Innovations, Inc.

Volatiles Investigating Polar Exploration Rover (VIPER)

Text Box 4, TextboxThe VIPER lunar robotic mission will directly analyze the surface and subsurface of the moon at various depths, light conditions, including permanently shaded regions, soil conditions and temperatures to determine the concentration of ice and other volatiles at the south pole of the moon. It will perform these surveys using its four science instruments, including a 1-meter drill, while roaming several miles across the surface of the moon. It is a challenging mission, with complex route planning to maximize battery charging and science opportunities within the quickly moving shadows cast by the sun shifting at low angles across the rough terrain at the south pole of the moon.

Crown has developed the onboard Fault Management (FM) system for VIPER using the Limit Checker (LC) component of the Core Flight System (cFS) the rover software is based on. We have :

  • Performed Failure Mode and Effects Analysis (FMEA) to identify potential failure modes in the system and their causes, effects and mitigations.
  • Developed the “Safing Table” spreadsheet, including failure scenario information; Watch Point telemetry specification, limit and testing information; Action Point logic, timing and response information.
  • Developed script systems to autocode the onboard safing tables from the spreadsheet that are integrated into the flight software.
  • Developed a unified units converter for a single point of truth for conversions within ground and flight software.
  • Developed an autocoded test system that implements Modified Condition/Decision Coverage (MC/DC) of the safing tables and integrates with the VIPER digital twin and Continuous Integration (CI) system

Benefit to NASA: In 2021, the undeveloped FM system was considered a significant project risk, and Crown was hired to address that risk. The highly automated system we developed for autocoding both the software and test system has retired that risk. It has become an essential element of rapid response to issues found in Systems Integration and Test.