Composite material used as a strain gauge

An apparatus, comprising a uniform composite foam including a non-layered mixture of a polymeric material with a plurality of voids; and a plurality of conductive fillers disposed in the polymeric material, the uniform composite foam producing a piezoelectric voltage, without an external current producing device, in response to being deformed. Strain, impact energy, and force sensors can provide vital information for many mechanics and dynamics applications. Some strain gauges are piezoresistive, meaning that the electrical conductivity of the gauge changes under pressure. Such gauges require a current source, for example a battery, to operate. Other strain gauges are piezoelectric, meaning that the gauge generates electric potential, in the form of a voltage that can be measured, under strain. Existing strain gauges are limited in terms of the magnitude of strain they can measure, primarily limited to strain ranges of 1-2% strain. Additionally, many such gauges are expensive, and difficult to calibrate, limiting the use of such gauges to laboratory settings. Of additional concern is the phenomenon of drift, which is defined as change in the mathematics of the calibration function with respect to time and or amount of use.