Abstract: Disclosed herein are various embodiments of a hydraulic actuator that includes one or more check valves having a dynamically varying cracking pressure. In certain embodiments, a hydraulic actuator may be configured to vary the cracking pressure of a check valve based on an operating condition of a pump of the hydraulic actuator. The check valve may be located along a bypass path in the hydraulic actuator, thereby allowing for fluid flow to bypass a pump of the hydraulic actuator by passing through the check valve. The use of such hydraulic actuators is contemplated in, for example, an active suspension system of a vehicle. Additionally, various embodiments of suitable check valves are disclosed. Additionally, methods are disclosed for operation of the check valve and the hydraulic actuator.

Abstract: Disclosed herein are various embodiments of a hydraulic actuator that includes one or more check valves having a dynamically varying cracking pressure. In certain embodiments, a hydraulic actuator may be configured to vary the cracking pressure of a check valve based on an operating condition of a pump of the hydraulic actuator. The check valve may be located along a bypass path in the hydraulic actuator, thereby allowing for fluid flow to bypass a pump of the hydraulic actuator by passing through the check valve. The use of such hydraulic actuators is contemplated in, for example, an active suspension system of a vehicle. Additionally, various embodiments of suitable check valves are disclosed. Additionally, methods are disclosed for operation of the check valve and the hydraulic actuator.

Abstract: Presented herein, inter alia, are suspension system components having tuned accumulator sizing and/or stiffness. Such suspension system components are envisioned for use in a distributed active suspension system of a vehicle. In particular, through appropriate sizing of accumulators of a suspension system component of a vehicle, ride quality of the vehicle may be improved and so called “rough ride” issues may be precluded. Alternatively or additionally, various valves or alternative compliant mechanisms may be included in the suspension system component, so that desirable performance may be obtained for a range of operating conditions.

Abstract: Integrated multiple actuator electro-hydraulic systems as well as their methods of use are described. Depending on the particular application, the integrated electro-hydraulic systems may exhibit different frequency responses and/or may be integrated into a single combined unit.

Abstract: Disclosed herein are hydraulic actuators and methods for the operation of actuators having variable relative pressure ratios. Further disclosed are methods for designing and/or operating a hydraulic actuator such that the actuator exhibits a variable relative pressure ratio. In certain embodiments, the relative pressure ratio of the hydraulic actuator may be dependent on one or more characteristics (such as, for example, frequency or rate of change) of an oscillating input to the hydraulic actuator.

Abstract: Integrated multiple actuator electro-hydraulic systems as well as their methods of use are described. Depending on the particular application, the integrated electro-hydraulic systems may exhibit different frequency responses and/or may be integrated into a single combined unit.

Abstract: Integrated multiple actuator electro-hydraulic systems as well as their methods of use are described. Depending on the particular application, the integrated electro-hydraulic systems may exhibit different frequency responses and/or may be integrated into a single combined unit.

Abstract: Integrated multiple actuator electro-hydraulic systems as well as their methods of use are described. Depending on the particular application, the integrated electro-hydraulic systems may exhibit different frequency responses and/or may be integrated into a single combined unit.

Abstract: Active suspension systems including actuators with combinations of accumulators and flow restrictions, as well as their methods of operation, are described. In some embodiments, methods and constructions for mitigating pump ripple and/or resonances between different hydraulic components are also described.

Abstract: Disclosed herein are hydraulic actuators and methods for the operation of actuators having variable relative pressure ratios. Further disclosed are methods for designing and/or operating a hydraulic actuator such that the actuator exhibits a variable relative pressure ratio. In certain embodiments, the relative pressure ratio of the hydraulic actuator may be dependent on one or more characteristics (such as, for example, frequency or rate of change) of an oscillating input to the hydraulic actuator.

Abstract: Active suspension actuator systems including an actuator with a compression volume and an extension volume are described. In some embodiments, the system includes one or more flow control devices in fluid communication with the compression volume and/or the extension volume of the actuator. In some instances, a flow control device may include a pressure balanced blow-off valve (PBOV). In some embodiments, the system includes a high capacity bidirectional base valve. In some embodiments, two or more flow control devices cooperate to, for example, damp low amplitude oscillations in the extension and/or compression volumes, and to allow the build-up of pump generated differential pressures while discharging rapid road induced differential pressure spikes between the extension and compression volumes.

Abstract: Integrated multiple actuator electro-hydraulic systems as well as their methods of use are described. Depending on the particular application, the integrated electro-hydraulic systems may exhibit different frequency responses and/or may be integrated into a single combined unit.

Abstract: Disclosed herein are hydraulic actuators and methods for the operation of actuators having variable relative pressure ratios. Further disclosed are methods for designing and/or operating a hydraulic actuator such that the actuator exhibits a variable relative pressure ratio. In certain embodiments, the relative pressure ratio of the hydraulic actuator may be dependent on one or more characteristics (such as, for example, frequency or rate of change) of an oscillating input to the hydraulic actuator.

Abstract: Integrated multiple actuator electro-hydraulic systems as well as their methods of use are described. Depending on the particular application, the integrated electro-hydraulic systems may exhibit different frequency responses and/or may be integrated into a single combined unit.

Abstract: Presented herein, inter alia, are suspension system components having tuned accumulator sizing and/or stiffness. Such suspension system components are envisioned for use in a distributed active suspension system of a vehicle. In particular, through appropriate sizing of accumulators of a suspension system component of a vehicle, ride quality of the vehicle may be improved and so called “rough ride” issues may be precluded. Alternatively or additionally, various valves or alternative compliant mechanisms may be included in the suspension system component, so that desirable performance may be obtained for a range of operating conditions.

Abstract: Disclosed herein are hydraulic actuators and methods for the operation of actuators having variable relative pressure ratios. Further disclosed are methods for designing and/or operating a hydraulic actuator such that the actuator exhibits a variable relative pressure ratio. In certain embodiments, the relative pressure ratio of the hydraulic actuator may be dependent on one or more characteristics (such as, for example, frequency or rate of change) of an oscillating input to the hydraulic actuator.

Abstract: Integrated multiple actuator electro-hydraulic systems as well as their methods of use are described. Depending on the particular application, the integrated electro-hydraulic systems may exhibit different frequency responses and/or may be integrated into a single combined unit.

Abstract: Disclosed herein are hydraulic actuators and methods for the operation of actuators having variable relative pressure ratios. Further disclosed are methods for designing and/or operating a hydraulic actuator such that the actuator exhibits a variable relative pressure ratio. In certain embodiments, the relative pressure ratio of the hydraulic actuator may be dependent on one or more characteristics (such as, for example, frequency or rate of change) of an oscillating input to the hydraulic actuator.

Abstract: Disclosed herein are various embodiments of a hydraulic actuator that includes one or more check valves having a dynamically varying cracking pressure. In certain embodiments, a hydraulic actuator may be configured to vary the cracking pressure of a check valve based on an operating condition of a pump of the hydraulic actuator. The check valve may be located along a bypass path in the hydraulic actuator, thereby allowing for fluid flow to bypass a pump of the hydraulic actuator by passing through the check valve. The use of such hydraulic actuators is contemplated in, for example, an active suspension system of a vehicle. Additionally, various embodiments of suitable check valves are disclosed. Additionally, methods are disclosed for operation of the check valve and the hydraulic actuator.

Abstract: In one embodiment, certain aspects of forces at a structural interface applied by one actuator are mitigated by a secondary actuator that applies a secondary force. In some embodiments the secondary actuator applies a static force. In yet another embodiment, an actuator is used to apply a force on a wheel assembly of a vehicle to detect and/or ameliorate the effect of certain tire incongruities.