Robust Chatter Stability Prediction of the Milling Process considering Uncertain Machining Positions

Table 4

Modal parameters of two different positions.

Direction	Modes	Position 1			Position 2
		Natural frequency ω (Hz)	Damping ratio ζ (%)	Stiffness K (×10^9 N/m)	Natural frequency ω (Hz)	Damping ratio ζ (%)	Stiffness K (×10^9 N/m)
X	1	504	1.98	0.88	484	5.37	0.66
	2	912	1.97	6.58	916	3.28	4.75
	3	1228	1.79	1.13	1252	3.99	5.47
	4	1392	3.00	0.39	1400	4.60	0.36
Y	1	384	2.08	1.49	380	4.21	3.74
	2	636	1.89	0.13	624	5.06	0.18
	3	1432	1.68	1.14	1408	4.83	1.72