Abstract: Apparatus and methods to automatically inspect precision tabletops used for vibration isolation are described. An inspection head having an imaging device and/or perturbing device can be positioned automatically at a plurality of locations over a precision tabletop. The inspection head can further include a distance sensor that can be used to determine a flatness of a portion or all of a surface of the precision tabletop. The inspection head may further include marking apparatus to automatically mark non-compliant features formed on the precision tabletop.

Abstract: Apparatus and methods to reduce unwanted motion in precision instruments are described. An active vibration-isolation system may include a feedback loop that senses motion of an intermediate mass. In noisy environments, where the feedback loop would otherwise fail or provide inadequate isolation, feedforward control can be implemented to sense floor vibrations and reduce motion of the intermediate mass that would otherwise be induced by the floor vibrations. The feedforward control can reduce motion of the intermediate mass to a level that allows the feedback loop to operate satisfactorily.

Abstract: Apparatus and methods to reduce unwanted motion in precision instruments are described. An active vibration-isolation system may include a feedback loop that senses motion of an intermediate mass. In noisy environments, where the feedback loop would otherwise fail or provide inadequate isolation, feedforward control can be implemented to sense floor vibrations and reduce motion of the intermediate mass that would otherwise be induced by the floor vibrations. The feedforward control can reduce motion of the intermediate mass to a level that allows the feedback loop to operate satisfactorily.

Abstract: A low-profile, vibration-damped tabletop for supporting sensitive scientific equipment is described. The tabletop may include a laminated structure having a lower metal plate that is sized to achieve a desired weight for the tabletop, a manufactured, homogenous filler and a “clean top” metal upper skin having a plurality of holes backed by liquid impermeable barriers. The damping characteristics are improved at low frequencies compared to a comparable structure with a honeycomb filler.

Abstract: A low-profile, vibration-damped tabletop for supporting sensitive scientific equipment is described. The tabletop may include a laminated structure having a lower metal plate that is sized to achieve a desired weight for the tabletop, a manufactured, homogenous filler and a “clean top” metal upper skin having a plurality of holes backed by liquid impermeable barriers. The damping characteristics are improved at low frequencies compared to a comparable structure with a honeycomb filler.

Abstract: Apparatus and methods to automatically inspect precision tabletops used for vibration isolation are described. An inspection head having an imaging device and/or perturbing device can be positioned automatically at a plurality of locations over a precision tabletop. The inspection head can further include a distance sensor that can be used to determine a flatness of a portion or all of a surface of the precision tabletop. The inspection head may further include marking apparatus to automatically mark non-compliant features formed on the precision tabletop.

Abstract: A precision tabletop for scientific instrumentation is described. The tabletop may be manufactured from as few as two pieces of material, include a honeycomb stiffening and vibration damping structure, be sealed from fluid ingress, include interior reinforcing structures, and permit accurate registration of machined features on all sides of the tabletop.

Abstract: Apparatus and methods to reduce unwanted motion in a payload of a precision instrument are described. The payload may be supported by an intermediate mass. A feedback signal based upon sensed motion of the intermediate mass may be applied to an intermediate-mass actuator arranged to drive the intermediate mass. Additionally, a feedforward signal may be applied to a payload actuator arranged to drive the payload and used to suppress unwanted motion of the payload. The feedforward signal may be derived from a source within the apparatus or external to the apparatus that would otherwise cause unwanted motion of the payload.

Abstract: Apparatus and methods to reduce unwanted motion in precision instruments are described. An active vibration-isolation system may include a feedback loop that senses motion of an intermediate mass. In noisy environments, where the feedback loop would otherwise fail or provide inadequate isolation, feedforward control can be implemented to sense floor vibrations and reduce motion of the intermediate mass that would otherwise be induced by the floor vibrations. The feedforward control can reduce motion of the intermediate mass to a level that allows the feedback loop to operate satisfactorily.

Abstract: Apparatus and methods to reduce unwanted motion in a payload of a precision instrument are described. The payload may be supported by an intermediate mass. A feedback signal based upon sensed motion of the intermediate mass may be applied to an intermediate-mass actuator arranged to drive the intermediate mass. Additionally, a feedforward signal may be applied to a payload actuator arranged to drive the payload and used to suppress unwanted motion of the payload. The feedforward signal may be derived from a source within the apparatus or external to the apparatus that would otherwise cause unwanted motion of the payload.

Abstract: Apparatus and methods to reduce unwanted motion in precision instruments are described. An active vibration-isolation system may be configured to receive a user-selectable setting, sense a stability of operation of the vibration-isolation system, and indicate whether the user-selectable setting provides stable vibration isolation. The settings may be changed by the user to improve vibration-isolation performance without requiring installation of the system by a skilled vibration-isolation engineer.

Abstract: Apparatus and methods to reduce unwanted motion in a payload of a precision instrument are described. The payload may be supported by an intermediate mass. A feedback signal based upon sensed motion of the intermediate mass may be applied to an intermediate-mass actuator arranged to drive the intermediate mass. Additionally, a feedforward signal may be applied to a payload actuator arranged to drive the payload and used to suppress unwanted motion of the payload. The feedforward signal may be derived from a source within the apparatus or external to the apparatus that would otherwise cause unwanted motion of the payload.

Abstract: A precision tabletop for scientific instrumentation is described. The tabletop may be manufactured from as few as two pieces of material, include a honeycomb stiffening and vibration damping structure, be sealed from fluid ingress, include interior reinforcing structures, and permit accurate registration of machined features on all sides of the tabletop.

Abstract: A low-profile, vibration-damped tabletop for supporting sensitive scientific equipment is described. The tabletop may include a laminated structure having a lower metal plate that is sized to achieve a desired weight for the tabletop, a manufactured, homogenous filler and a “clean top” metal upper skin having a plurality of holes backed by liquid impermeable barriers. The damping characteristics are improved at low frequencies compared to a comparable structure with a honeycomb filler.

Abstract: An active damping system for use in connection with a vibration isolation system includes an intermediate mass between a base and an isolated payload. The intermediate mass is supported by at least one support element which also supports at least substantially all of the static forces of the isolated payload. An actuator dampens and isolates dynamic forces acting on the intermediate mass from the isolated payload. The active damping system also includes a payload support element and a passive damping element, both of which are coupled at one end to the payload platform and at an opposite end to the intermediate mass. A sensor is affixed to the intermediate mass to generate a feedback signal to a processor coupled to the actuator.

Abstract: An active damping system for use in connection with a vibration isolation system includes an intermediate mass between a base and an isolated payload. The intermediate mass is supported by at least one support element which also supports at least substantially all of the static forces of the isolated payload. An actuator dampens and isolates dynamic forces acting on the intermediate mass from the isolated payload. The active damping system also includes a payload support element and a passive damping element, both of which are coupled at one end to the payload platform and at an opposite end to the intermediate mass. A sensor is affixed to the intermediate mass to generate a feedback signal to a processor coupled to the actuator.

Abstract: An active damping system for use in connection with a vibration isolation system includes an intermediate mass between a base and an isolated payload. The intermediate mass is supported by at least one support element which also supports at least substantially all of the static forces of the isolated payload. An actuator dampens and isolates dynamic forces acting on the intermediate mass from the isolated payload. The active damping system also includes a payload support element and a passive damping element, both of which are coupled at one end to the payload platform and at an opposite end to the intermediate mass. A sensor is affixed to the intermediate mass to generate a feedback signal to a processor coupled to the actuator.

Abstract: An active damping system for use in connection with a vibration isolation system includes an intermediate mass between a base and an isolated payload. The intermediate mass is supported by at least one support element which also supports at least substantially all of the static forces of the isolated payload. An actuator dampens and isolates dynamic forces acting on the intermediate mass from the isolated payload. The active damping system also includes a payload support element and a passive damping element, both of which are coupled at one end to the payload platform and at an opposite end to the intermediate mass. A sensor is affixed to the intermediate mass to generate a feedback signal to a processor coupled to the actuator.

Abstract: An active vibration damping system having a supporting spring for addressing a static force from a payload, and an independent actively isolated damper positioned in parallel between a payload and a source of vibration for damping dynamic force from the payload to an actively isolated point. The actively isolated damper includes a small intermediate mass, distinct and decoupled from the payload mass, and a passive isolator element for dynamic coupling of the isolated platform to the small intermediate mass. The small intermediate mass provides a point to which dynamic forces from the payload may be dampened. The active damper also includes at least one actuator coupled at one surface to the small intermediate mass and coupled at a second surface to the vibrating base platform. A motion sensor may also be provided on the small intermediate mass so as to generate a feedback signal as a function of the movement of the small intermediate mass.

Abstract: A pneumatic isolator for isolating payloads from vibrations consisting of a vertical isolator suspended from pendulum wires. The top load surface of the isolator strongly resists tilt, thus improving payload stability.