In-Situ Soil Gas Analysis with a Robust Sawsensor System Integrated in Percussion Driven Penetration Cones

We present the first integration of a SAW sensor based sensor system (electronic nose) into a percussion driven penetration cone for in situ soil gas analysis. The system includes an 8-fold SAW sensor array with different polymers as sensitive coatings, sampling system with absorbent materials for the selective enrichment of analytes, inlet system for probing ambient soil, rechargeable battery pack and a remote control to an external PC on ground via Bluetooth. By means of an integrated spring based mechanical decoupling system measurements could be performed even during penetration of the cone via a pneumatic hammer! Proper operation of sensor system was possible until soil depths of 8m!