7 June 2017
I was the Surface Properties Scientist, or SPS on staff today. The SPS has an interesting job, in that the SPS helps Rover Planners (called RPs) assess the terrain around the rover with safety in mind, first and foremost.
There are two main jobs of an SPS. The first is to assess how likely the rover is to slip in its current position, called the Slip Risk Assessment Process (SRAP). Is it on a stable footing, like thin sand cover over smooth rocks, or is a wheel perched on a ledge? The reason this is important is because as MSL‘s arm is articulated to conduct contact science, a perched rover wheel might slip and cause damage to the arm by contact between the turret and the ground. That would be bad! Today we were on a solid surface and passed SRAP without any concerns.
The other job of the SPS is to help the RPs find a safe path forward if there is a drive planned. On some sols this is a very taxing job, other days not so much. Today was in the middle. The RPs use high resolution digital terrain models generated from imagery taken from the previous sol after the latest drive to plan a safe path to the next stopping point, while avoiding rocks, ledges, and deep sand. The RPs confer with the SPS to evaluate the proposed route making any modifications necessary along the way. Today, the path directly ahead was pretty rough, so the drive was planned to dodge some angled rocks, and head back towards the Mount Sharp Ascent Route and ultimately the Vera Rubin Ridge.
Written by Christopher Edwards, Planetary Geologist at Northern Arizona University