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: At least one controller configured to control an actuator of an active suspension system. The at least one controller includes circuitry configured to determine an actuator state, and apply the actuator state and a commanded state to an inverse model of the actuator to produce an actuator command. The circuitry is configured to produce the actuator command by a process that includes performing low pass filtering and phase compensation to correct a phase introduced by the low pass filtering.

Abstract: Method and apparatus for improving the performance, response, and durability of an electro-hydraulic active suspension system. The noise caused by hydraulic flow ripple is reduced and system response is improved.

Abstract: An apparatus and method are described where one or more pre-stressed spring elements are disposed between two structures to mitigate or cancel the effect of static loads applied to a component connecting the structures. The apparatus and methods may be used, for example, to reduce the adverse impact of static loads on the performance of top-mounts in a suspension system of a vehicle.

Abstract: A self-driving vehicle with an integrated fully-active suspension system. The fully-active suspension utilizes data from one or more sensors used for autonomous driving (e.g. vision, LIDAR, GPS) in order to anticipate road conditions in advance. The system builds a topographical map of the road surface. Suspension and road data is delivered back to the vehicle in order to change autonomous driving behavior including route planning. Energy storage is regulated based on a planned route. Forward and lateral acceleration feel is mitigated through active pitch and tilt compensation. The fully-active suspension pushes and pulls the suspension in three or more operational quadrants in order to deliver superior ride comfort, handling, and/safety of the vehicle.

Abstract: Various embodiments related to hydraulic actuators and active suspension systems as well as their methods of use are described.

Abstract: Apparatus and methods are described where multiple linear and/or rotary actuators operate cooperatively in, for example, cross-linked arrangements to control the motion of sprung and unsprung masses in a vehicle. The actuators may include linear primary suspension actuators, spring perch actuators and/or rotary roll-bar actuators that, in some operating modes, are driven directly or indirectly by one or more hydraulic machines.

Abstract: An apparatus and method are described where one or more pre-stressed spring elements are disposed between two structures to mitigate or cancel the effect of static loads applied to an component connecting the structures. The apparatus and methods may be used, for example, to reduce the adverse impact of static loads on the performance of top-mounts in a suspension system of a vehicle.

Abstract: A method of on-demand energy delivery to an active suspension system is disclosed. The suspension system includes an actuator body, a hydraulic pump, an electric motor, a plurality of sensors, an energy storage facility, and a controller. The method includes disposing an active suspension system in a vehicle between a wheel mount and a vehicle body, detecting a wheel event requiring control of the active suspension; and sourcing energy from the energy storage facility and delivering it to the electric motor in response to the wheel event.

Abstract: In one embodiment, one or more suspension systems of a vehicle may be used to mitigate motion sickness by limiting motion in one or more frequency ranges. In another embodiment, an active suspension may be integrated with an autonomous vehicle architecture. In yet another embodiment, the active suspension system of a vehicle may be used to induce motion in a vehicle. The vehicle may be used as a testbed for technical investigations and/or as a platform to enhance the enjoyment of video and/or audio by vehicle occupants. In some embodiments, the active suspensions system may be used to perform gestures as a means of communication with persons inside or outside the vehicle. In some embodiments, the active suspensions system may be used to generate haptic warnings to a vehicle operator or other persons in response to certain road situations.

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.

Abstract: In one embodiment, one or more suspension systems of a vehicle may be used to mitigate motion sickness by limiting motion in one or more frequency ranges. In another embodiment, an active suspension may be integrated with an autonomous vehicle architecture. In yet another embodiment, the active suspension system of a vehicle may be used to induce motion in a vehicle. The vehicle may be used as a testbed for technical investigations and/or as a platform to enhance the enjoyment of video and/or audio by vehicle occupants. In some embodiments, the active suspensions system may be used to perform gestures as a means of communication with persons inside or outside the vehicle. In some embodiments, the active suspensions system may be used to generate haptic warnings to a vehicle operator or other persons in response to certain road situations.

Abstract: In some embodiments, a rapid-response active suspension system controls suspension force and position for improving vehicle safety and drivability. The system may interface with various sensors that detect safety critical vehicle states and adjust the suspension of each wheel to improve safety. Pre-crash and collision sensors may notify the active suspension controller of a collision and the stance may be adjusted to improve occupant safety during an impact while maintaining active control of the wheels. Wheel forces may also be controlled to improve the effectiveness of vehicle safety systems such as ABS and ESP in order to improve traction. Also, bi-directional information may be communicated between the active suspension system and other vehicle safety systems such that each system may respond to information provided to the other.

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: An apparatus and method are described where one or more pre-stressed spring elements are disposed between two structures to mitigate or cancel the effect of static loads applied to an component connecting the structures. The apparatus and methods may be used, for example, to reduce the adverse impact of static loads on the performance of top-mounts in a suspension system of a vehicle.

Abstract: In some embodiments, a rapid-response active suspension system controls suspension force and position for improving vehicle safety and drivability. The system may interface with various sensors that detect safety critical vehicle states and adjust the suspension of each wheel to improve safety. Pre-crash and collision sensors may notify the active suspension controller of a collision and the stance may be adjusted to improve occupant safety during an impact while maintaining active control of the wheels. Wheel forces may also be controlled to improve the effectiveness of vehicle safety systems such as ABS and ESP in order to improve traction. Also, bi-directional information may be communicated between the active suspension system and other vehicle safety systems such that each system may respond to information provided to the other.

Abstract: A method of on-demand energy delivery to an active suspension system is disclosed. The suspension system includes an actuator body, a hydraulic pump, an electric motor, a plurality of sensors, an energy storage facility, and a controller. The method includes disposing an active suspension system in a vehicle between a wheel mount and a vehicle body, detecting a wheel event requiring control of the active suspension; and sourcing energy from the energy storage facility and delivering it to the electric motor in response to the wheel event.

Abstract: Presented herein are systems and methods for controlling a response (e.g., a roll, a pitch) of a vehicle body to a driver input. In one aspect, a method for controlling the response of the vehicle body is presented, the method comprising receiving an input (e.g., a steering wheel input, a pedal input) from an operator of a vehicle and modifying an aspect (e.g., a roll angle, a pitch angle, a roll rate, a pitch rate) of the response of the vehicle body, the modified aspect having a value based, at least partially, on the input. In another aspect, a controlled vehicle is presented comprising a vehicle body and one or more actuators configured to apply a torque to the vehicle body, the torque having a direction and/or magnitude based, at least partially, on a driver input (e.g. steering command, braking command, and/or acceleration command).

Abstract: A method of on-demand energy delivery to an active suspension system comprising an actuator body, hydraulic pump, electric motor, plurality of sensors, energy storage facility, and controller is provided. The method comprises disposing an active suspension system in a vehicle between a wheel mount and a vehicle body, detecting a wheel event requiring control of the active suspension; and sourcing energy from the energy storage facility and delivering it to the electric motor in response to the wheel event.