초록 ▼

A vibration isolation and precision pointing device, and a related method for its operation, for reducing vibrational disturbances on a payload platform, which is subject to vibration transmitted from a base platform and to other possible vibrational disturbances applied directly to the payload itse

A vibration isolation and precision pointing device, and a related method for its operation, for reducing vibrational disturbances on a payload platform, which is subject to vibration transmitted from a base platform and to other possible vibrational disturbances applied directly to the payload itself or to the payload platform. The invention includes a complementary combination of passive isolation and active isolation in parallel between the base and payload platforms, together with a precision positioning system that greatly reduces vibration at very low frequencies. Each isolation device, of which there are three pairs arranged to damp vibration in three axes, includes, in one embodiment, a passive spring to reduce coupling of vibration at higher frequencies and to fulfill a static load bearing function, and an active actuator element, in the form of a voice coil actuator, for applying active compensation over a selected bandwidth of frequencies below that over which passive isolation is most effective. Another disclosed form of each isolation device includes an elastic tube bendable by piezoelectric actuators and having a flexure that transmits the bending force to the payload platform along a single selected axis. In one preferred embodiment of the invention, three pairs of isolation devices are arranged on mutually orthogonal planes that intersect at the center of mass of the payload. As a result, translational vibration in the orthogonal planes is decoupled from rotation of the payload.

대표청구항 ▼

[ What is claimed is:] [1.] A semi-active vibration isolator, comprising:a plurality of isolator devices connected between a first platform and a second platform which is to be isolated with respect to the first platform, wherein each of the isolator devices includesa passive isolator element having

[ What is claimed is:] [1.] A semi-active vibration isolator, comprising:a plurality of isolator devices connected between a first platform and a second platform which is to be isolated with respect to the first platform, wherein each of the isolator devices includesa passive isolator element having a first end connected to the first platform and a second end connected to the second platform, wherein the passive isolator element reduces the effect of vibratory disturbances over a limited band of frequencies,an active isolator element connected to operate in parallel with the passive isolator element, between the first and second platforms, the active isolator element having a first end connected to the first end of the passive isolator element and a second end connected to the second end of the passive isolator element, the active isolator element functioning to compensate for vibratory disturbances over a selected frequency band complementing the effect of the passive isolator element, anda sensor attached to the isolator device for sensing internal strain or stress in the isolator due to vibratory disturbances;a damping control circuit responsive to signals from the sensor, for generating signals to control the active isolator element in such a manner as to compensate for the vibratory disturbances; andan angular positioning control circuit, for generating actuator control signals to correct angular positioning errors in the second platform.