Experimental modal analysis deals with vibration of dynamic structures. Measuring system’s responses and excitations helps to predict structure’s dynamics and determine critical frequencies that can compromise safety or operation of a dynamic system, i.e. plane wing, suspension bridge, tennis racket, etc. With experimental modal analysis the process of modal testing is applied with the help of measurement devices and sensors that are used for acquiring system’s excitation and response data. Main outcome of the modal testing is a frequency response function which is actually a transfer function of a linear time invariant system and carries information of natural frequencies, stiffness and damping. This work presents the process of modal testing and basics of further modal analysis for determining dynamic properties of a system of interest in order to examine its behaviour at different frequencies. Dewesoft software and hardware is used for a practical example of a modal testing process.
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