CMU MHCI '04

Project Overview

Mars Exploration Rover Missions

The Mars Exploration Rovers (MER), Spirit and Opportunity, are robotic geologists executing a series of science investigations on the surface of Mars. As the rovers complete the Surface Operations phase of their mission, a team of scientists on Earth, the Athena Science Team, choose activities for the rover to execute in order to conduct remote science experiments on Mars, with the goal of uncovering clues about the presence of water on Mars and its impact on the Martian environment.

The Athena Science Team is composed of over 200 scientists from all over the world, with a subset of those scientists collaboratively defining rover activities at MER Mission Control at the Jet Propulsion Laboratory (JPL). The team is divided into 5 theme groups, geology, mineralogy, atmospheric, soil, and long term planning, with science team leads guiding the science activity planning within each group.

The rovers operate on a schedule based on Martian days, or sols. Each sol is essentially split into 3 phases: downlink, science assessment, and uplink. During the downlink phase, mission control receives data from the rover, including the health of the rover and the data products resulting from the previous sol’s science activities. The scientists then review the data received from the rover and begin to plan the next sol’s activities during the science assessment phase. Scientists must not only choose the activities that should be executed, but they must determine the relative priority of the activities to be executed and the retrieval of the data products that they will produce. The final phase, uplink, is when the activities specified by the scientists are sequenced and prepared for transmittal to the rover for execution. Our focus is on the science assessment phase of the sol, which can be further divided into 8 distinct periods, which we will refer to as the science activity planning process.

The mission was initially intended to last 90 sols (Martian days), due to expected rover resource limitations, however the mission has extended well beyond 90 sols. We will refer to the first 90 sols of the mission as the Primary Mission and the remaining sols as the Extended Mission. We were provided with the opportunity to study the science activity planning process for several sols during both phases of the mission.