Shock Hardened, High Resolution Inductive Sensing Accelerometer

KaZaK Composites and Kaman Fuzing offer a novel accelerometer concept using inductive sensing. The concept promises shock resistance, high sensitivity and resolution, flat frequency response, DC capability, high resonance, and to eliminate the brittleness problems with piezoresistive instruments. It is intended for initial application in penetrating weapons, and will be suitably hardened for the shock environment. It will be an enabling technology for distributed fuzing, which was highlighted in the topic description. Outputs of direct local sensing by instruments disposed about the weapon body could be integrated to give both rigid-body dynamics and body strains, to alleviate the need for shock isolation of a centrally mounted processor. The accelerometer is proposed to be built of extremely high specific stiffness composite materials for reduced physical distortion and improved linearity under high G loadings. One objective will be to show that the specific stiffness of a practical composite at instrument scale can exceed that of beryllium, the benchmark for conventional inertial sensors. In Phase I the team will work toward a benchtop-level test article for laboratory demonstration of the concept. The team will also pursue preliminary design of a prototype instrument, mounting method and interconnection hardware to survive the weapon production process. BENEFITS: The immediate prospects for a new capability in high shock accelerometers include improvement to the reliability of penetrator fuzing, and enabling technology for distributed fuzing. Ultimately, these factors will result in an important tactical advantage. Aside from the military applications, the commercial potential should be at least equal to that of existing accelerometers. The high resolution of the inductive sensing instrument is promises for many applications, and the new type should find a niche in high-precision vibration monitoring in fields such as transport vehicle dynamics, aerospace, machine tools, and research. The sensitivity of the inductive type may also prove of use for relatively low accelerations, such as seismic measurements.