Impact Locating Using Piezoceramic Circular Beam Sensors

Abstract

AbstractIn this paper, a piezoceramic circular beam sensor is designed and tested to apply for locating an impact position on a glass plate. Since a glass plate shows a dispersive property in frequency response, the circular beam sensor is made as a cantilever type which can provide a narrow band response. The narrow-band property of the sensor is critically important to estimate the impact locating because the bending wave velocity is constant at a certain frequency. Two of those sensors were made and attached at 150 mm and 300 mm away from the center of a glass plate which has the dimension of 800 * 800 * 6 mm (length * width * thickness). After applying an impact at the center on the glass plate, the two circular sensors detect impact signals which are narrow banded. Then the exact impact point was calculated precisely using the cross-correlation function of the measured two impact signals. The impact locating with two commercial accelerometers did not give right results because the accelerometers generate broadband response which makes the determination of the bending wave velocity very difficult. Thus this piezoceramic circular beam sensor could be utilized to implement a large touch screen with less cost.Keywordsimpact sensorpiezoceramic circular beamcross-correlation function