Pressure sensors that can provide both high temporal and spatial resolutions are desired for the measurement of aerodynamic and acoustic events, ultrasonics, and underwater phenomena. Piezoelectric materials are attractive candidates for measuring dynamic pressure due to their high sensitivity, high signal-to-noise ratio, and potential for miniaturization. However, their inability to directly measure static pressure prevents their use in many applications. Due to their strong pyroelectric response, their use is also generally limited to conditions where the rate of temperature change is below the lower cutoff frequency of the measurement system. Polyvinylidene fluoride (PVDF) is a polymer with a high piezoelectric sensitivity which is readily available as a flexible, tough film. Under steady ow conditions, configuring PVDF as a cantilever unimorph provides a higher pressure sensitivity than alternatives such as compressive, doubly clamped, or diaphragm configurations. In this work, we demonstrate a differential aerodynamic pressure sensor based on a cantilever PVDF unimorph that has been optimized to maximize pressure sensitivity for a targeted deflection sensitivity. The sensor is characterized using a laboratory-scale wind tunnel for flows ranging from 0 to 12 ms-1. Near-static measurements are enabled by a compensated charge amplifier with an extremely low cutoff frequency. The pyroelectric voltage generated from changes in the air ow temperature is compensated using a PVDF sensor in compressive mode. Within the tested pressure range of 0 to 80 Pa, the sensor exhibits a proportional response with a sensitivity of 0.97 mV Pa-1.
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