Robotic Lunar Geotechnical Tool

Abstract

Rover-mounted geotechnical systems are of paramount importance to lunar trafficability assessment, construction, and excavation/mining toward establishing permanent human presence on the Moon. These tools can also be used to determine density, when the regolith is used as radiation shield, for example. Two popular in-situ devices for establishing geotechnical properties of soil are the Static Cone Penetrometer (SCP) and Dynamic Cone Penetrometer (DCP). However, both systems have shortcomings that may prevent them from being robotically-deployed in a low gravity environment. In this paper we describe an alternative system, called the Percussive Dynamic Cone Penetrometer (PDCP) that can be used to robotically-measure geotechnical soil properties in a low gravity environment. It is shown that PDCP data correlates well with the data obtained from both SCP and DCP testing, and by extension with California Bearing Ratio (CBR) and soil bearing strength.