Use of Terrain-Based Analysis in Mission Design, Planning and Modeling of Operations of a Lunar Exploration Rover

The starting point for planning planetary surface exploration missions begins with deciding upon a landing site. TeamIndus, who participated in the Google Lunar XPRIZE (GLXP) competition to soft-land a Lander on the Moon, had to perform detailed studies on the terrain at the chosen landing area to ensure that the mission’s objectives were achievable. The main objectives of the mission were: (i) to achieve a stable and soft-landing of the Lunar Lander (HHK-1) and (ii) to operate a surface exploration Rover over a distance of at least 500 m with the Lander serving as a communication relay between earth and the Rover. Two aspects of terrain analysis are discussed in this chapter: (i) design inputs used for antenna design on the Lander and the Rover, and (ii) terrain and line-of-sight (LoS)-based reachability analysis to the 500-m periphery from touchdown coordinates carried out for the Rover and its use in path planning. Lunar Reconnaissance Orbiter (LRO)-Narrow-Angle Camera (NAC) SDNDTM data product served as the source dataset for this analysis. The results brought out firm recommendations to increase the antenna height on both the Lander and the Rover, and thereby extend the range of the Rover communication on the lunar surface. A global path planning (GPP) methodology incorporating the above analysis is laid out considering that the landing point is localized to within 20 m of known landmarks on the selenographic map constituted by LRO-NAC images of the landing area. This feature-based landmark map once overlaid on a derived LoS hazard map is used to perform a grid-based cost minimization for deriving waypoints for reaching a destination at 500 m from the Lander.