Isolation System for an Industrial Process Equipment Subject to Random Vibration

  The support structure of a massive, 110,000 lb, industrial process equipment, subject to random perturbation, is isolated from the vibration of the equipment itself.  The isolators used in the random vibration isolation system are made up of low-stiffness springs paired with viscous dampers. Motion control schemes were incorporated into the isolation system to manage […]

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Advanced Air Isolation System for Precision Devices

Precision devices such as coordinate measuring machines (CMMs), microscopes, MRI machines, and other test/scanning equipment are highly sensitive to vibration, caused by other nearby equipment or even human activities. The adverse effects of vibration on such devices should be mitigated by properly isolating them from the surrounding via elastically mounting them on their support concrete […]

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Active Stiffness Control of Air-Mounted Systems

Air mounts, with their attractive attribute of being able to provide the most softness of all mounts of comparable size, have been gaining popularity and widespread use. The drawback of soft mounting is occasional excessive motion of the mounted machine in response to abrupt, impulse-like disturbances (such as starting up or shutting down an engine). […]

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Active Damping of Air-Mounted Systems

Compared to elastomeric (rubber) and coil spring mounts, air mounts with their very low stiffness, provide the highest degree of low-frequency vibration isolation. Lack of damping in air mounts, although lowers the noise and vibration transmission of the mounted machine, will deteriorate its shock isolation attributes. This is mainly due to the creation of a […]

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Computer Controlled Air Isolation System

An Advanced Mounting System for Diesel Generators Onboard Luxury Watercrafts An ideal mounting system for yacht diesel generators should be ‘soft and highly underdamped’, while the yacht is not moving, i.e., the propulsion engines are off and calm and quiet are expected. This will prevent the transmission of vibration and noise, through the hull, to […]

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Structure-borne Transformer Noise Reduction by Air Isolation

Transformer noise (hum) is caused by the extension and contraction of the core laminations when magnetized (a phenomenon is known as magnetostriction). This extension and contraction (vibration) take place twice during a normal voltage or current cycle. That is, the transformer vibrates mainly at twice the frequency of the supply, i.e. 120 Hz in North […]

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Air Isolation of a Diesel Generator

To lower the vibration transmitted from a 170 KVA diesel generators onboard a super yacht, to the hull (and thus the living quarters) of the boat, it was decided to soft mount that diesel-generator by changing its conventional (elastomeric) mounts to air mounts. The attachment of the exhaust pipe to the engine, as well as […]

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One-Order Tuned Vibration Absorption of a Diesel-Generator

In four stroke engines, including diesel engines driving generators, each cylinder fires every other revolution. This causes the engine vibration to occur at ½ the engine RPM, called the ½ order vibration, and its higher order harmonics namely 1 order, 1½ order, 2 order. In the case of a diesel generator, in addition to the […]

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A Kalman Estimator-Based Active Vibration Isolation Strategy

A novel, feed-forward vibration isolation scheme is developed that addresses the shortcomings of adaptive feedforward vibration isolation algorithms. This scheme which is based on the use of Kalman estimators (KE) does not require real-time adaptation and yet maintains its effectiveness when the attributes (such as the frequencies) of the disturbance changes. More importantly, it does […]

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