SUPER SPRING -- A NEW TYPE OF LOW-FREQUENCY VIBRATION ISOLATOR

A new type of mechanical isolating device called Super Spring has been devised. The Super Spring uses the fact that a mass suspended by a long spring is effectively isolated (from mechanical vibrations) for all frequencies higher than the system's natural resonance. A method has been developed for electronically terminating a 30 cm-long spring in such a way that the mass suspended from it behaves as if the spring were one kilometer or longer in length. This permits mechanical isolation from frequencies as low as 0.02 Hz. The principles of this new device, the results of both shake-table and free-fall tests, and the implications of this technique for measurement science are described.