Modal and Natural Frequency Sensitivity Analysis of Electrohydraulic Stewart Platform

Table 3

Modal frequencies and corresponding modal shapes of the Stewart platform in Case (b).

Vibration modes of each degree of freedom of upper platform	Moving along the X-axis	Moving along the Y-axis	Moving along the Z-axis	Rotate along the X-axis	Rotate along the Y-axis	Rotate along the Z-axis
Frequency (Hz)	20.2278	20.4584	58.1965	82.6201	83.5604	41.1358
Modal vibration mode	1	0.2417	−0.0110	0.0381	−0.1592	0.0033
	−0.2417	1	−0.0063	0.1504	0.0406	−0.0081
	0.0075	0.0072	1	0.0140	−0.0131	0.0173
	0.0407	−0.1488	−0.0090	1	0.2700	0.0217
	0.1575	0.0383	0.0139	−0.2700	1	0.0122
	0.0041	−0.0050	0.0087	0.0088	0.0085	−1