Multi-Sleeve Friction Penetrometer as Complement to Portable Bevameter for Lunar and Martian Terrain Assessment Studies

This paper describes a recently developed multi-sleeve friction penetrometer that has the potential to play an important role in future Lunar and Martian terrain assessment studies to better measure and understand the mechanical properties of soils, as they relate to compaction and shear under a wheel or track. In contrast to other terrain assessment systems, this device allows for multiple simultaneous measurements of soil response in a single test sounding and thus the interpretation of the test results can be performed in terms of both absolute as well as relative response values. This is possible since interchangeable friction sleeves with surfaces of different roughness values allow for soil response as a function of shear surface characteristics to be evaluated. Testing with the newly developed device can be performed simultaneously with other well established technologies (e.g. cone penetration testing, shear wave velocity testing). In addition, the design of the device is well suited for deployment using remotely controlled robotic systems. An overview of the multi-sleeve friction penetrometer is presented, along with typical results obtained using the device.