Negative-stiffness vibration isolation improves reliability of nanoinstrumentation

Vibration-isolation systems have become an economical choice for nanotechnology applications. Passive negative-stiffness isolators use a unique and completely mechanical concept in low-frequency vibration isolation. Vertical-motion isolation is provided by a stiff spring that supports a weight load, combined with a negative-stiffness mechanism (NSM). The net vertical stiffness is made very low without affecting the static load-supporting capability of the spring. Beam columns connected in series with the vertical-motion isolator provide horizontal-motion isolation. The horizontal stiffness of the beam columns is reduced by the beam-column effect. Negative-stiffness isolators offer other advantages over air systems that include they do not require an air supply or dedicated, large nitrogen tanks. The negative-stiffness isolator is a passive isolation approach, and has a key advantage in that it requires no electricity.