Patent ID: 8061677

Claim:
A mounting system for mounting machinery, and for isolating vibration therefrom, the system comprising: (a) a support for said machinery, including a plurality of resilient mounts, each mount comprising a passive resilient means for fully supporting the static load of the machinery, active isolation means, and an upper mounting plate and an opposing lower mounting plate, wherein the active isolation means are mounted to at least one of the upper mounting plate and the lower mounting plate, and wherein the passive resilient means are positioned between the upper mounting plate and the lower mounting plate; (b) a control means for controlling the stiffness of the mounts as a function of frequency, which control means is coupled to the active isolation means; and the control means comprising: (i) means for sensing motion of the support, the means for sensing being mounted to the support such that motion arising from both excited resonances and rigid body modes of motion is sensed; (ii) means for filtering, from the sensed motion, displacement arising from excited resonances to determine the motion of the mount due to rigid body modes of motion; (iii) means for calculating modal restoring forces; and (iv) means for applying local demand forces to each said resilient support for compensating for rigid body modes of motion; and wherein the control means is arranged such that: (i) below the mount resonant frequency a performance parameter of each support is essentially that of the passive resilient means; and (ii) above the mount resonant frequency and over a desired frequency band, forces generated by the passive resilient means in response to local displacements of the passive resilient means are essentially cancelled out by the active isolation means in order to maintain a zero stiffness of the support to excited structural resonances.