Improving Sequence Traceability During Testing and Review for the Mars Science Laboratory

While operating spacecraft, many teams break operations planning into two processes. One process focuses on planning for the upcoming cycle, while another process governs the development of unique activities that require careful study, testing, and review before they are ready for use in flight. While developing unique activities that require extra testing and review, teams often make use of testbeds on earth to ensure the activity is well planned and that sequences of commands are compatible with hardware and software configurations. Despite careful tracking, it can be easy for mistakes to creep in before sequence delivery and uplink while teams are testing and iterating over difference sequence versions. For example, a sequence that required an update for success in the testbed could have an earlier version inadvertently submitted to the flight sequence database. The Engineering Operations team for NASA's Mars Science Laboratory Curiosity Rover had a desire to improve the traceability of these sequences as they are tested, reviewed, and uplinked. This paper details the design, development, and implementation of a new tool that uses the Sequence Checksum to make it easier for operators to prove three key things during the review process. First, that the sequences evaluated in the testbed match what has been delivered to the sequence database for use in flight. Second, that all sequences being delivered as part of an activity were indeed tested. Third, that all sequences necessary for activity completion have been delivered to the sequence database. While this may be trivial to accomplish for simple activities, keeping track of all this information can be difficult for activities that include tens of sequences. This paper will discuss the design and usefulness of the tool, and also the overall activity review and approval process.