The Mobile Micro Penetrometer

Means for sub-surface investigations are of great interest for the exploration of planetary bodies such as the Moon, Mars and comets, in the future scenarios intending to send probes to their surfaces. To this aim, in-depth penetration may be performed either by drilling or by self-propelled devices. To reach a depth of several meters in loose to hard compact soil, self-propulsion has a great advantage of simplicity over drilling, as it does not require the complex autonomous assembly of several drill sections. The mobile penetrometer presented here is an original device of this category. As payload, this exploration device may carry various sensors, for instance, thermal, seismic, optical, or a camera lens. It may be implemented with in-situ analysis devices, or be used to take and retrieve samples at various depths. The current prototype has a diameter of 1.9 cm, length 32.5 cm, a mass 0.4 kg, and an average power consumption of 2 W (max. 5 W). Further size and mass reduction to diameter 1.3 cm, length 25 cm and 0.25 kg are feasible. An approximately equivalent mass is estimated for the penetrometer support and release system, which supports the penetrometer at the start of penetration. The principle of this mobile penetrometer has been invented and patented by the Russian Mobile Vehicle Engineering Institute (VNIITRANSMASH) in St. Petersburg, which has already built a large size functional prototype. They developed its miniaturisation and spatialisation for the requirements of cometary, Moon and Mars environment in the frame of an European Space Agency (ESA) study led by Tecnospazio, in which DLR is responsible for testing.