| Popis: |
Flight and ground integration is an ongoing challenge in the development of deep-space mission operations systems. Separate development teams and schedules exacerbate the problem. Enhancing the operability of the flight and ground interactions has proven to be a strategy that reduces both cost and risk. One of the first areas of operability addressed has been the commanding and sequencing system. Virtual machine language (VML) sequencing was developed to improve operability and has now been used on 15 NASA deep-space missions, most recently on NASA’s Mars Atmosphere and Volatile Evolution (MAVEN) mission. Onboard adaptation to new missions has taken the form of data-driven configuration of the VML software for command and variable definitions without changes to underlying flight code, dramatically reducing cost and risk. Continuity in capability has allowed new VML mission sequencing to be based on products from prior missions, which are then modified as necessary to accommodate different hardware capabilities. In conjunction with the NASA Small Business Innovative Research (SBIR) program, “Reactive Rendezvous and Docking Sequencer,” improvements incorporated into the various versions of VML since 1998 allow VML scripts to perform much of the work that formerly would have required expensive flight software development. The latest version, VML 3.0, has been enhanced to include reactive state machines for autonomous management of critical spacecraft operations, object-oriented element organization, and matrix/ vector operations. |
