Free-Decay Nonlinear System Identification via Mass-Change Scheme

Table 2

Identified modal parameters of the 4-DOF system.

Mode	Frequency (Hz)		Damping (%)
	Unmodified	Set I	Unmodified
1	2.88	2.75	0.29
2	14.69	14.00	0.97
3	16.03	15.28	1.01
4	17.76	16.93	1.09