Experimental modal analysis of a multi-degree-of-freedom system with random parametric excitation and non-linear damping

✍ Scribed by Takeshi Kawashima; Taro Shimogo

• Publisher: Elsevier Science
• Year: 1990
• Tongue: English
• Weight: 752 KB
• Volume: 4
• Category: Article
• ISSN: 0888-3270
• DOI: 10.1016/0888-3270(90)90019-h

✦ Synopsis

Though there are many non-linear systems in use, the experimental modal analysis techniques are based on the linear system. In this paper, an experimental modal analysis technique for a multi-degree-of-freedom system with random parametric excitation and non-linear damping being proportional to the squared velocity is proposed. This technique is developed from examining a stability condition for the covariance of response given by applying the perturbation technique to a stochastic differential equation, which is derived by the mode decoupling, the statistical linearization and other assumptions.

Additionally, experiments were carried out to identify the modal parameters with the aid of the proposed technique, the technique was confirmed with analytical solutions.