Parameter identification of weakly nonlinear vibration system in frequency domain

Article type: Research Article

Authors: Peng, Jiehua^; | Tang, Jiashi | Chen, Zili^;

Affiliations: Department of Mechanics, Hunan University, Changsha, 410082, P.R. China | Department of physics, Shaoyang University, Shaoyang, 422000, P.R. China | College of Architectural Engineering, Central South Forestry University, Zhuzhou, 412008, P.R. China

Note: [] Corresponding author. E-mail: Pengjhua@sina.com

Abstract: A new method of identifying parameters of nonlinearly vibrating system in frequency domain is presented in this paper. The problems of parameter identification of the nonlinear dynamic system with nonlinear elastic force or nonlinear damping force are discussed. In the method, the mathematic model of parameter identification is frequency response function. Firstly, by means of perturbation method the frequency response function of weakly nonlinear vibration system is derived. Next, a parameter transformation is made and the frequency response function becomes a linear function of the new parameters. Then, based on this function and with the least square method, physical parameters of the system are identified. Finally, the applicability of the proposed technique is confirmed by numerical simulation.

Keywords: parameter identification, weakly nonlinear vibration system, least square method, frequency domain

Journal: Shock and Vibration, vol. 11, no. 5-6, pp. 685-692, 2004