Earth vibrators, such as servo-hydraulic vibrators, are improved to produce more output force and less distortion at very low frequencies by capturing mass from the vehicles which carry them, adding sufficient inertial mass to the reaction mass without adding much vehicle and equipment weight while also avoiding increases to the servo-hydraulic vibrator's stroke length. In particular, improvements to servo-hydraulic vibrators, at low frequencies, will couple some mass from the carrier vehicle frame and its load using non-rigid coupling only when additional mass is needed using dampers connected between the reaction mass and the carrier vehicle's frame, with the added damping being applied by a control system at very low frequencies of output where the vibrator is otherwise unable to produce force equal to its hold-weight.

An orifice plate includes a wear-resistant inner diameter surface, an outer diameter surface, a first side surface extending between the wear-resistant inner diameter surface and the outer diameter surface, and a second side surface extending between the wear-resistant inner diameter surface and the outer diameter surface, the second side surface disposed opposite the orifice plate from the first side surface. The orifice plate may comprise a body portion comprising a first material. The wear-resistant inner diameter surface may comprise a second, wear-resistant material.

Earth vibrators, such as servo-hydraulic vibrators, are improved to produce more output force and less distortion at very low frequencies by capturing mass from the vehicles which carry them, adding sufficient inertial mass to the reaction mass without adding much vehicle and equipment weight while also avoiding increases to the servo-hydraulic vibrator's stroke length. In particular, improvements to servo-hydraulic vibrators, at low frequencies, will couple some mass from the carrier vehicle frame and its load using non-rigid coupling only when additional mass is needed using dampers connected between the reaction mass and the carrier vehicle's frame, with the added damping being applied by a control system at very low frequencies of output where the vibrator is otherwise unable to produce force equal to its hold-weight.

A vibration isolator has a bearing body that is supported on at least two air springs, wherein each air spring has a chamber which is closed by a membrane and to which compressed air can be applied.

The present application discloses embodiments of a vibration isolation assembly configured to reduce the communication of excitation vibration between a supporting surface and a payload, at excitation frequencies significantly higher than the resonant frequency of the isolator. In one embodiment, the vibration isolation assembly includes a housing assembly having a housing body with a pneumatic chamber formed therein, wherein the housing assembly is supported by the supporting surface. The pneumatic chamber is configured to accept at least one fluid therein. A mass engaging member configured to support at least a portion of the payload is supported by the pneumatic chamber, and at least one thermally conductive member in thermal communication with the housing body is positioned within the pneumatic chamber. The thermally conductive member is configured to transfer thermal energy from the fluid in the pneumatic chamber to the housing body and into the ambient environment.

A wheel assembly to be coupled to a hub of a vehicle may include an inner rim to be coupled to the hub of the vehicle, an outer rim surrounding the inner rim, and gas springs operatively coupled between the inner rim and the outer rim to provide a gas suspension permitting relative movement between the inner rim and the outer rim. Each of the gas springs may include a gas cylinder having an inner surface, and a piston movable within the gas cylinder. The piston may include a shaft, a piston head coupled to the shaft and having at least one recess therein, and at least one biasing member within the at least one recess. Each gas spring may also include at least one damping member adjacent the at least one biasing member and within the at least one recess to frictionally engage the inner surface of the gas cylinder.

A vibration isolator (10; 210) for supporting a payload and isolating the payload from vibrations has a contact member (12) configured for supporting the payload, at least two pressurized gas compartments (24) arranged offset from each other to support the contact member at different locations, which pressurized gas compartments are connected to each other via a tubing system (54). The tubing system contains at least one restriction (66) at which a cross section of the tubing system is reduced by at least 50%.

A machine learning apparatus determines a control parameter of an active vibration isolation apparatus on which an industrial machine is mounted. The industrial machine includes a movable part, a drive source that drives the movable part, and a drive source control section that controls the drive source to position the movable part at a command position. The machine learning apparatus includes: an acquiring section that acquires, as teacher data, a positional deviation, which is a difference between the command position and an actual position of the movable part; a storage section that stores a learning model that outputs the control parameter corresponding to a state quantity concerning the industrial machine; and a learning section that updates the learning model using the teacher data.

The invention provides a vibration isolation system (IS), comprising a piston (402) to carry a payload, a connecting member (410), a spring (404) and a flexible member (408). The spring is arranged to support the piston along a direction with a positive stiffness. The flexible member is arranged to apply a force to the piston along the direction via the connecting member with a negative stiffness.

An orifice plate may include a body portion comprised of a non-metallic material, and a metallic wear insert, wherein the metallic wear insert defines an inner diameter surface of the orifice plate and the body portion defines an outer diameter surface of the orifice plate.