Harmonic-Balance-Based parameter estimation of nonlinear structures in the presence of Multi-Harmonic response and force

• A nonlinear system identification method using Harmonic Balance is developed. The proposed capable of accurately identifying non-smooth nonlinearity. performance demonstrated numerically and experimentally. can deal with the effects higher harmonics in input force outputs. effect model error measurement noise shown. Testing structures to characterise their internal forces challenging. Often are excited by harmonic yield a multi-harmonic response. In many systems, particularly ones strong nonlinearities, responses cannot be ignored. Even if intended excitation single frequency sinusoidal force, interaction shaker structure lead applied force. these on structural dynamics often neglected. objective this study introduce an method, motivated alternating frequency/time approach balance (AFTHB), which able consider both system. AFTHB include all significant selecting appropriate time step sampling guarantee accuracy results. An analytical harmonic-balance-based (AHB) also considered for comparison. However, inclusion response expansion functions cumbersome. Furthermore, easily cope complex nonlinearities such as Coulomb friction multi-degree freedom systems. Including process reduces approximation due truncation very accurate balanced equations each obtained. requires prior knowledge or estimation type nonlinearities. selection may used set candidate models, avoiding dictionary arbitrary basis significantly computational costs. This paper highlights important features ensure four simulated two experimental examples. number considered, modelling error, range quality estimated demonstrated.