Acoustic Micro-Opto-Mechanical Transducers for Crack Width Measurement on Concrete Structures from Aerial Robots

A novel Micro-Opto-Mechanical acoustic sensor that can be utilized to measure the width of surface opening cracks in concrete structures from aerial robots is presented. The sensor is used in combination with a piezoelectric emitter operating at 54 kHz in a crack width measurement procedure that provides a resolution around 0.2 mm. The method is tolerant to pressure variations during contact with concrete, which may easily occur when operating the sensors from aerial robots.