Science Operations Planning and Implementation for the OSIRIS-REx Mission, Part 2: Toolkit

The OSIRIS-REx mission to asteroid (101955) Bennu comprised multiple phases, each with objectives that posed unique complexities for planning and implementation of science and optical navigation observations. In response to these challenges, the Science Planning Team (SPT) and the Implementation Team (IpT) at the University of Arizona amassed a toolkit composed of both in-house and commercial tools and scripts to accomplish reliable production of safe, high-fidelity flight products on a rapid, tactical planning timeline. J-Asteroid was the primary planning and implementation tool used by SPT and IpT. Built upon the geospatial information system JMARS (Java Mission-planning and Analysis for Remote Sensing), it was developed by Arizona State University's Mars Space Flight Facility. Configurable to the mission design, J-Asteroid modeled ephemerides, asteroid shape and spin state, spacecraft trajectory, navigation uncertainty, slew and attitude profile, instrument systems, and instrument command sequencing for new observation plans. A front-end interface enabled design of spacecraft scan patterns, ability to incorporate automated commanding or an ingested library of blocks, and two- and three-dimensional visualization of instrument footprints over a global Bennu shape model. J-Asteroid checked plans against a comprehensive database of flight rules and constraints and against perturbed trajectories. J-Asteroid's Integrated Commanding Tool converted finalized plans into delivery packages. JPlanner2, a Java-based tool, automated the processing of J-Asteroid delivery packages through scripts to generate, compile, and test flight products. JPlanner2 calculated data volume, generated activity plots, performed flight rule and soft constraint checks, and produced build reports and artifacts for delivery to the Spacecraft Operations Team at Lockheed Martin. Activity Inspector was an in-house tool that produced an integrated spacecraft attitude profile and confirmed compliance with spacecraft and instrument pointing constraints, which allowed continuous and rapid verification of J-Asteroid plans. Activity Inspector generated standardized pointing telemetry products for stakeholder communication. The tool performed analyses of Monte Carlo sets of perturbed trajectories, allowing for assessment of plan stability and produced visualizations by compiling the transmitted plan against the reconstructed trajectory. SPOCFlight was an in-house, server-based data system with a web interface. This event-driven system managed, parsed, calibrated, and packaged ground, spacecraft, and science data, and enabled users to monitor data, generate reports, and execute Activity Inspector. Several planning and implementation tools and processes leveraged data products available on SPOCFlight. A library of instrument command blocks was developed to perform repeated functions, such as instrument calibrations and optical navigation imaging. Complex blocks worked with J-Asteroid to produce observation-specific sequencing. Validated blocks were stored in a spacecraft library and initiated from onboard instrument sequences. Python scripts for analysis parsed text and JSON reports output by J-Asteroid to produce tables, graphs, and additional computations, further enabling evaluation of observation plans. The scripts provided increased user efficiency. Git repositories were used to configuration-manage SPT scripts and IpT-generated flight products. JIRA, a commercial off-the-shelf work management software, was used to organize unique issue types for both SPT and IpT. The JIRA workflow included gated reviews as observations moved through planning, implementation, execution, and downlink. The OSIRIS-REx science operations toolkit of in-house and commercial tools enhanced efficiency, reduced risk, and increased flight product robustness.