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 active suspension system is configured in a strut arrangement. The active suspension system comprises a hydraulic actuator and a hydraulic pump/electric motor assembly, wherein the actuator movement is preferably in lockstep with the hydraulic motor-pump and electric motor-generator combination. Torque in the electric motor is instantaneously controlled by a controller to create an immediate force change on the hydraulic actuator. The hydraulic actuator is configured so that it can be used as a strut whereby the actuator has sufficient structural rigidity to carry the applied suspension loads while capable of supplying damper forces in at least three quadrants of the force velocity graph of the suspension actuator operation. Embodiments disclosed include low cost active suspension systems for a MacPherson strut application.

Abstract: This disclosure describes a method for performing BSR testing on a vehicle with an active suspension system, the method including actuating at least one actuator of the active suspension system to induce vibration of a vehicle or at least one component of the vehicle at a first frequency, recording a first acoustic response generated by the vehicle or the at least one component in response to the induced vibration at the first frequency, and analyzing the first recorded acoustic response to identify a presence of one or more manufacturing defects associated with the vehicle or the at least one component. This disclosure also describes a method for characterizing resonance frequencies of a vehicle equipped with an active suspension system.

Abstract: A linear energy harvesting device that includes a housing and a piston that moves at least partially through the housing when it is compressed or extended from a rest position. When the piston moves, hydraulic fluid is pressurized and drives a hydraulic motor. The hydraulic motor drives an electric generator that produces electricity. Both the motor and generator are central to the device housing. Exemplary configurations are disclosed such as monotube, twin-tube, tri-tube and rotary based designs that each incorporates an integrated energy harvesting apparatus. By varying the electrical characteristics on an internal generator, the kinematic characteristics of the energy harvesting apparatus can be dynamically altered. In another mode, the apparatus can be used as an actuator to create linear movement.

Abstract: Systems and methods for determining the location of a vehicle are disclosed. In one embodiment, a method for localizing a vehicle includes driving over a first road segment, identifying by a first localization system a set of candidate road segments, obtaining vertical motion data while driving over the first road segment, comparing the obtained vertical motion data to reference vertical motion data associated with at least one candidate road segment, and identifying, based on the comparison, a location of the vehicle. The use of such localization methods and systems in coordination with various advanced vehicle systems such as, for example, active suspension systems or autonomous driving features, is contemplated.

Abstract: Presented herein are systems and methods for attenuating certain pulsations in a hydraulic system comprising a pump and a hydraulic actuator. In certain aspects, an accumulator comprising an internal volume that is divided into a working chamber and a contained chamber may be utilized to at least partially attenuate propagation of certain pulsations in the system. The working chamber may be fluidically coupled to the pump via a first flow path and fluidically coupled to a chamber of the actuator via a second flow path. The system may be designed such that a first inertance of the first flow path is greater than a second inertance of the second flow path. Additionally or alternatively, the system may be designed such that a resonance associated with the first inertance and a compliance of the accumulator may occur at a resonance frequency of less than 90 Hz.

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: 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.

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: A linear energy harvesting device that includes a housing and a piston that moves at least partially through the housing when it is compressed or extended from a rest position. When the piston moves, hydraulic fluid is pressurized and drives a hydraulic motor. The hydraulic motor drives an electric generator that produces electricity. Both the motor and generator are central to the device housing. Exemplary configurations are disclosed such as monotube, twin-tube, tri-tube and rotary based designs that each incorporates an integrated energy harvesting apparatus. By varying the electrical characteristics on an internal generator, the kinematic characteristics of the energy harvesting apparatus can be dynamically altered. In another mode, the apparatus can be used as an actuator to create linear movement.

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: Presented herein are systems and methods that allow for adapting at least one dimension of an accumulator in a hydraulic system when faced with certain dimensional constraints and to vary the compliance or stiffness of an accumulator.

Abstract: An active suspension system is configured in a strut arrangement. The active suspension system comprises a hydraulic actuator and a hydraulic pump/electric motor assembly, wherein the actuator movement is preferably in lockstep with the hydraulic motor-pump and electric motor-generator combination. Torque in the electric motor is instantaneously controlled by a controller to create an immediate force change on the hydraulic actuator. The hydraulic actuator is configured so that it can be used as a strut whereby the actuator has sufficient structural rigidity to carry the applied suspension loads while capable of supplying damper forces in at least three quadrants of the force velocity graph of the suspension actuator operation. Embodiments disclosed include low cost active suspension systems for a MacPherson strut application.

Abstract: A linear energy harvesting device that includes a housing and a piston that moves at least partially through the housing when it is compressed or extended from a rest position. When the piston moves, hydraulic fluid is pressurized and drives a hydraulic motor. The hydraulic motor drives an electric generator that produces electricity. Both the motor and generator are central to the device housing. Exemplary configurations are disclosed such as monotube, twin-tube, tri-tube and rotary based designs that each incorporates an integrated energy harvesting apparatus. By varying the electrical characteristics on an internal generator, the kinematic characteristics of the energy harvesting apparatus can be dynamically altered. In another mode, the apparatus can be used as an actuator to create linear movement.

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.