Data Gathering
Mission Analysis
We first observed the MER Science Activity Planning Process roughly half way through the Primary Mission. We were strictly observing the process, with no communication with the people we were observing. We divided into two teams, with each team observing the entire planning process for 2-3 sols, operating on Mars time. We consolidated our observation data and defined the high-level process which we observed.
MER Science Activity Planning Process
1. Science Context Meeting
The science activity planning process begins with the Science Context Meeting. At this meeting, the previous sol’s successes and failures are reviewed, and the high-level science goal for the current planning sol is determined. For example, if the goal of the current planning sol is to drive the rover to a particular location, this would be presented at the science context meeting. There may also be a report from the long term planning theme group with a rough outline for the rover’s resources and high-level activities for the upcoming sols. There is an opportunity for all scientists to voice their opinion about the current planning sol goals, and also for them to receive
2. Science Downlink Assessment
The Science Downlink Assessment is the period during the planning day when
the scientists review the data sent from the rover to inform their planning
decisions for the current planning sol. They are typically working within
their theme groups, and are using an application called Science Activity Planner
(SAP) to review the activities from the previous sol and to begin to specify
the activities for the current planning sol.
3. Science Downlink Assessment Meeting
During the Science Downlink Assessment Meeting, the scientists are provided
with information on the health of the rover, as well as information on the
health of each of the rover’s instruments. The theme groups also report
the results from the previous sol’s data.
4. Science Activity Planning
Scientists create activities for next sol within SAP. They are able to specify
some of the details of the activities which they are creating in SAP, but
must distribute some of the specification to instrument specialists.
5. Science Operations Working Group (SOWG) Meeting
The SOWG Meeting is the time when scientists work together to choose the activities
that the rover will execute on the surface of Mars. This meeting is lead by
the SOWG chair, the scientist with the most authority over the planning process.
The SOWG chair is aided by the SOWG documentarian, who must record all of
the details of the discussion, including the scientific intent related to
activities.
During this meeting, each theme group lead presents the activities that they would like the rover to execute, including the scientific purpose for the activity. The entire group then decides which activities to execute, and prioritizes the activities based on various factors including resource limitations and scientific intent. The scientists must also prioritize the retrieval of the data products resulting from the activities that they specify at this meeting. Activities can have a high uplink priority, meaning that it is very important for that activity to be executed, but a low downlink priority, meaning that the data from that activity can remain in the rover’s memory until downlink resources are available to transmit the data product. Rover engineering activities and rover and instrument health are also reviewed.
6. Constraint Editing and Planning
An engineer, the Tactical Activity Planner (TAP) applies constraints specified
by the scientists using an application called Constraint Editor, and then
imports the constrained activities into MAPGEN, an optimized planner. The
SOWG documentarian works with the TAP to maintain scientific intent as the
constraints are applied and the rover plan is generated and manipulated. The
activities in the rover plan can be a subset of the activities approved during
the SOWG Meeting, and additional activities not specified in the SOWG may
be added into the plan at this point in the process based on available rover
resources.
7. Activity Plan Tagup
During the Activity Plan Tagup, the TAP, SOWG chair, SOWG documentarian, instrument
specialists, and other stakeholders review first iteration of plan. They review
the sequence generated by the planner to ensure that scientific intent is
maintained and that the desired resource levels are maintained. The TAP revises
the plan using Constraint Editor and MAPGEN.
8. Final Activity Plan Review
During the Activity Plan Tagup, the TAP, SOWG chair, SOWG documentarian, instrument
specialists, and other stakeholders review final iteration of plan before
it is sequenced for the rover.
Primary Mission
During the Primary Mission, the Athena Science Team members located at JPL, as well as all other people involved in rover operations, lived on Mars time, with each sol revolving around the communication windows with the rover and the science planning cycle. The science assessment phase was very long (10+ hours per sol), and was followed rigorously, with the participants learning much about the rover, the Martian environment, and the planning process as the mission progressed. Early in the mission, the rover plan was not well defined early in the planning process, with many changes to the plan occurring at the SOWG and later in the process. As the rover executed more plans successfully, the scientists learned more about the planning process and the limitations of the rover, and accumulated executed activities to re-use in future plans. Re-using these previously executed activities added an additional validation to the planning process. In some cases, templates were created to facilitate planning and activity re-use.Extended Mission
The Extended Mission differed from the Primary Mission in a number of ways. Due to budget constraints, the mission began to operate on Earth time, with only a subset of the Athena Science Team members who had been located at JPL during the Primary Mission able to remain working on the mission full time, making the theme groups much smaller. Additionally, the remaining members became experts at creating rover plans, so the plan was often defined very early in the planning process, sometimes even days ahead of time. There was often a very detailed plan created in Microsoft Excel containing many of the details that would not have been available until after the Constraint Editing and Planning portion of the science activity planning process during the Primary Mission.The planning process no longer revolved around the rover’s schedule,
but operated on more normal Earth working hours, and was often accelerated,
with meetings combined or eliminated sometimes. The new schedule sometimes
created mismatches between when rover data was obtained and when it was needed.
However, the experience of the team members and the corpus of previously executed
activities lessened the impact of this mismatch in some cases.
