Aeroshell Skin-based Navigation for Inertial Navigation Enhancement

Without GPS, inertial navigation systems (INS) face accumulating positional uncertainty from integrating accelerations measured with finite noise to estimate velocity and the integration of velocities (incorporating integrated noise) to estimate positions. A system is developed providing decreased positional uncertainty by incorporating arrays of piezoelectric and piezoresistive sensing elements on the inner (protected) surface of an air vehicle’s aeroshell or a surface or undersea vehicle’s hull (both hereafter termed aeroshell). By measuring vibration and deformation of the aeroshell in response to static and dynamic pressure loading, convective velocity and surface pressure are measured and, from these, freestream velocity and pressure are deduced. The pressure measurements reveal altitude/depth, and the combination of the freestream velocity with INS and magnetometer inputs allow more accurate knowledge of a vehicle’s vector velocity by limiting positional uncertainty.