Systems, devices, and methods for active vibration control using circular force generators. In one aspect, a vehicle includes a vehicle frame, a cabin, an engine, and a number of vibration control devices mounted on the vehicle frame. Each vibration device includes a circular force generator comprising at least one mass and at least one motor configured to rotate the mass. The vibration control devices are configured to perform active vibration control to reduce noise and/or vibration within the cabin resulting from the engine deactivating a subset of cylinders in operation.

A vibration isolation device for optimally decoupling shear forces that are orthogonal to the principal direction of isolation from microvibrations. A pivoting load support element is free to pivot about a pivot point in response to shear forces, with optimal isolation from coupling to the principal direction of vibration isolation. A friction free bearing for small motion is provided to respond to the forces perpendicular to the principal direction of vibration isolation. An internal load support plate associated with the pivoting element is supported by equalizing springs and is damped by an active actuator driven according to a sensor on the internal load support plate. Adjustment points, such as screws, adjust the pivoting element with respect to the fixed pivot point.

A vehicle suspension system comprising a hydropneumatic strut comprising a fluid interface, where supply of hydraulic fluid to the strut via the fluid interface causes the overall length of the strut to increase, and withdrawal of hydraulic fluid via the fluid interface causes the overall length of the strut to decrease, a first displacement system in fluid communication with the fluid interface, capable of supplying and withdrawing fluid to and from the strut as well as measuring the volume of fluid supplied or withdrawn from the strut, a second displacement system in fluid communication with the fluid interface, and a hydraulic fluid source for selectively supplying or withdrawing hydraulic fluid from the hydropneumatic strut via either of the first or second displacement systems.

A method for reshaping an electric drive signal of a real-time damper in a sprung mass system includes detecting a periodic frequency and magnitude of a target periodic vibration of a sprung mass. The periodic vibration has velocity and elasticity components that are 90 degrees out-of-phase. An electric drive signal to the real-time damper is reshaped by a controller depending on polarity of the velocity component to thereby generate a composite drive signal. The damper is energized using the composite drive signal to modify a damper force. Reshaping the electric drive signal includes injecting a force and/or an intermittent drive suppression component onto the electric drive signal based on the frequency and magnitude. The sprung mass system may have a frame and body, motion and wheel speed sensors, the real-time dampers, road wheels, and a controller programmed to perform the method.

Aircraft landing gear strut breakout friction values are used to correct measured strut pressure as related to the amount of weight supported; with the ability to generate and refine the breakout friction value database, and a further ability to predict a future breakout friction correction value by trending historical measurements, as compared to recent measurements, as further compared to real-time breakout friction values. The system is used in monitoring, measuring, computing and displaying the weight and center of gravity for aircraft utilizing telescopic oleo landing gear struts. Pressure sensors, temperature sensors, humidity sensors, axle deflection sensors, accelerometers, inclinometers are mounted in relation to landing gear struts to monitor, measure and record strut pressure as related to strut telescopic movement, rates of strut telescopic movement, axle deflection, current temperature, current relative humidity, vertical acceleration; experienced by landing gear struts, as the aircraft proceeds through typical ground and flight operations.

A vehicle weight measurement device includes a diaphragm which covers an opening area of a groove portion of a mounting part to form an oil chamber of a predetermined space together with the groove portion; a pressure sensor which detects a change in pressure of measurement fluid in the oil chamber; a first piston which presses the diaphragm; a second piston which presses the first piston; and a bearing unit interposed between the second piston and a spring bush which receives one end of a spring of a suspension device and is relatively rotatable. The bearing unit includes a thrust needle bearing which swingably supports a load in a longitudinal direction of the suspension device, and a slide bush which does not receive a load in the longitudinal direction and receives a load in a radial direction while causing constant damping to swinging.

A telescopic arrangement (10) having a hollow cylinder (12) and a part (14) which is telescopically engaged with the cylinder. The arrangement is provided with at least one coil (22) constituting a first form of pulse-induction device, and at least one target (28) constituting a second form of pulse-induction device, to monitor the position of the said part (14) relative to the cylinder (12). A plurality of devices (22) each of one of the said first and second forms of device are positioned on the outside of the cylinder (12), at different respective positions therealong. At least one (28) of the other of the said first and second forms of device is fixed relative to the said part (14) of the arrangement (10) in a position such that it is moved over the said plurality of devices (22) in succession as the said part (14) is telescopically moved relative to the cylinder (12) of the arrangement (10).

A resilient bearing pad or support includes resilient material and a sensor that is configured to measure one or more of acceleration, velocity, variations in load, etc. of a mass supported by the bearing pad. The sensor may be configured to wirelessly transmit data for storage and/or evaluation. The data may be evaluated utilizing predefined criteria to detect and/or predict failure of the pad and/or a mass supported by the pad.

A method for controlling vehicle motion is described. The method includes accessing a set of control signals including a measured vehicle speed value associated with a movement of a vehicle. A control signal associated with user-induced input is also accessed. The method compares the measured vehicle speed value with a predetermined vehicle speed threshold value to achieve a speed value threshold approach status, and then compares the set of values to achieve a user-induced input threshold value approach status. The method monitors a state of a valve within the vehicle suspension damper, and determines a control mode for the vehicle suspension damper. The method also regulates damping forces within the vehicle suspension damper.

A vibration isolation device for optimally decoupling shear forces that are orthogonal to the principal direction of isolation from microvibrations. A pivoting load support element is free to pivot about a pivot point in response to shear forces, with optimal isolation from coupling to the principal direction of vibration isolation. A friction free bearing for small motion is provided to respond to the forces perpendicular to the principal direction of vibration isolation. An internal load support plate associated with the pivoting element is supported by equalizing springs and is damped by an active actuator driven according to a sensor on the internal load support plate. Adjustment points, such as screws, adjust the pivoting element with respect to the fixed pivot point.