An Ultra-Low Frequency Two DOFs’ Vibration Isolator Using Positive and Negative Stiffness in Parallel

Table 5

The magnitude of vibration transmissibility curves in different directions.

Direction	Frequency	PS magnitude (Experiment)	PNSP magnitude (Experiment)	Decreasing amplitude PS resonance/10 Hz
	PS resonance/10 Hz	18.34 dB/−18.61 dB	−10.99 dB/−31.90 dB	29.33dB/13.29 dB
	PS resonance/10 Hz	18.36 dB/−14.65 dB	−11.45 dB/−31.44 dB	19.48dB/16.79 dB
	PS resonance/10 Hz	16.78 dB/−18.24 dB	−10.59 dB/−34.78 dB	27.37dB/16.54 dB