Small Area Inertial Navigation Tracking (SAINT) System for Precise Location of Buried UXO

Geophysical technologies for supporting munitions waste remediation have focused on the problems of detecting, locating, and mapping the presence of underground objects. Experience has shown that most underground objects detected by these systems present no safety hazard or need to be excavated. If reliable means of distinguishing hazardous from nonhazardous objects could be developed, significant resources for munition remediation programs could be saved and more effectively deployed to mitigate safety hazards. Other researchers have shown a likelihood of being able to characterize buried targets via sophisticated inversion algorithms. These algorithms require high-fidelity sensor systems combined with high-fidelity positioning systems. Existing sensor technologies provide good quality sensor data, but practical high-resolution positioning systems (on the order of 1 cm error) remain a challenge. ENSCO, Inc. conducted a demonstration at Aberdeen Proving Grounds (APG) on September 12- 13, 2006, of the second generation small area inertial navigation tracking system (SAINT) technology integrated with an EM61-HH metal detector. The primary objective of this demonstration was to demonstrate a relative position accuracy of the EM61-HH sensor of less than 2 cm (one standard deviation) along each of the three axes of the local positioning reference frame. This demonstration highlighted the integration of SAINT with a standard EM61-HH metal detector. The primary objective was to verify the three-dimensional (3-D) positioning accuracy of the EM61-HH sensor provided by SAINT. Because no communication is needed with auxiliary components or satellites, normal operation is not affected by heavy vegetation, elevation change, water, or tree cover, as is the case for most other positioning systems. During postprocessing, the EM61-HH data was merged with the SAINT position data; however, the overall performance of the EM61-HH was not assessed. The focus was on the position accuracy. Prepraed in collaboration with ENSCO, Inc., Springfield, VA.