The increasing use of sensors is currently revolutionizing the construction industry. Laser Doppler vibrometers have become smaller, lighter and more powerful than ever before. They are perfectly suited for mobile and in-field use. Examples are measurements of pipelines and line vibrations in industrial plants, vibrations of railroads for identification of material failure, measurements on bridges that are subject to excitation by traffic, and vibrations of buildings. They are also suitable for vibration measurements in the lab on scale-models of structures.
Railroad authorities all over the world are interested in improving the efficiency of their rail defect detection systems. This field of structural health monitoring of railroad tracks is currently limited by the measurement technique which involves a relatively old technology that produces imperfect reliability of defect detection and limited inspection speed. Optomet laser Doppler vibrometry is being evaluated to overcome drawbacks of conventional rail testing. Ultrasonic waves are propagated through the railroad track and interact with a defect. These waves are measured by the Optomet laser Doppler vibrometer, which has exceptional sensitivity and signal strength, which is critical to obtaining data free from noise and drop outs on rusted and optically uncooperative surfaces where surface treatment is not possible. The goal of the research is to develop a reliable defect detection system that can be operated from regular passenger cars travelling at normal speeds.