Understanding Modal Analysis

This article reviews the fundamentals of vibration theory and discusses how the concepts used in describing the motion of single mass-spring-damper system can be extended to describe the motion of structures and systems via modal analysis. The material presented progresses from a discussion of a single mass-spring-damper system to modal properties of multi degree of freedom systems to frequency response and mode superposition methods. Although these techniques are not new, the intent is to present the fundamentals of modal analysis for those not already well acquainted with the theory and techniques involved.