Dynamic ground hook control in vehicles using active suspension systems

Abstract

The vehicle may include a vehicle body, a plurality of wheels, an active suspension system operably coupled to the plurality of wheels and the vehicle body, and at least one processor configured to control the active suspension system. The at least one processor may be configured to determine a first force command based on a vehicle body parameter, determine a second force command based on the vehicle body parameter and the suspension parameter, determine a mixing ratio based on the first force command, determine a third force command based at least in part on the mixing ratio, the first force command, and the second force command, and command at least one actuator to apply a force between at least one of the plurality of wheels and the vehicle body based at least in part on the third force command.

Description

[Technical Field]

[0001] Related Applications

[0001] This application claims the benefit of priority under 35 U.S.C. §119(e) to U.S. patent application Ser. No. 63 / 438,134, filed January 10, 2023, and U.S. patent application Ser. No. 63 / 405,645, filed September 12, 2022, the disclosures of which are hereby incorporated by reference in their entireties.

[0002] Field FIELD OF THE INVENTION

[0002] The disclosed embodiments relate to dynamic ground hook control in vehicles that use active suspension systems, and related methods. [Background technology]

[0003] background

[0003] Suspension systems are typically designed to properly support and orient a vehicle, handle safely in a variety of expected operating environments, and ensure a comfortable ride for occupants. Traditional suspension systems are typically passive, with fairly constant operating and performance parameters. Some suspension systems are semi-active in that their overall response can be adjusted by varying the damping forces applied by these semi-active systems, for example, to compromise between occupant comfort and vehicle handling. Fully active suspension systems use actuators to react to changes in road conditions using a combination of active and damping forces, depending on the operating mode, which is controlled using input from sensors and other measurement devices. Summary of the Invention [Means for solving the problem]

[0004] overview In some embodiments, a vehicle includes a vehicle body, a plurality of wheels, an active suspension system operably coupled to the plurality of wheels and the vehicle body, the active suspension system including at least one actuator configured to apply an active force to at least one of the plurality of wheels in at least one mode of operation, and at least one processor configured to control the active suspension system, wherein the at least one processor is configured to determine a first force command based on a vehicle body parameter, determine a second force command based on the vehicle body parameter and the suspension parameter, determine a blending ratio based on the first force command, determine a third force command based at least in part on the blending ratio, the first force command, and the second force command, and command the at least one actuator to apply a force between at least one of the plurality of wheels and the vehicle body based at least in part on the third force command.

[0005]

[0005] In some embodiments, a method for controlling a vehicle includes determining a first force command based on a vehicle body parameter, determining a second force command based on the vehicle body parameter and a suspension parameter, determining a blending ratio based on the first force command and determining a third force command based at least in part on the blending ratio, the first force command, and the second force command, and commanding at least one actuator of an active suspension system to apply an active force between at least one of a plurality of wheels of the vehicle and a vehicle body of the vehicle based at least in part on the third force command.

[0006]

[0006] It should be appreciated that the foregoing concepts, and additional concepts discussed below, may be arranged in any suitable combination, as the disclosure is not limited in this respect. Further advantages and novel features of the present disclosure will become apparent from the following detailed description of various non-limiting embodiments when considered in conjunction with the accompanying drawings.

[0007] BRIEF DESCRIPTION OF THE DRAWINGS

[0007] The accompanying drawings are not intended to be drawn to scale. In the drawings, each identical or nearly identical component illustrated in various figures may be represented by the same numeral. For clarity, not every component is labeled in every figure. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a schematic diagram of one embodiment of a vehicle including an active suspension system. [Figure 2]

[0009] 1 is a schematic diagram of an embodiment of a vehicle under vehicle body isolation control. [Figure 3]

[0010] 1 is a schematic diagram of an embodiment of a vehicle under road following control. [Figure 4]

[0011] FIG. 1 is a schematic diagram of an embodiment of a vehicle under mixed vehicle-body separation and road-following control. [Figure 5]

[0012] FIG. 1 is a block diagram of an embodiment of a vehicle control system. [Figure 6]

[0013] 1 is a flow diagram of an embodiment of a method for controlling a vehicle. [Figure 7]

[0014] 10 is a flow chart of another embodiment of a method for controlling a vehicle. DETAILED DESCRIPTION OF THE INVENTION

[0009] Detailed Description

[0015] In conventional vehicles, the vehicle suspension may be responsible for controlling multiple vehicle motion parameters. Such vehicle motion parameters may include, but are not limited to, roll, heave, pitch, and twist. In some cases, active suspension may be used in a vehicle to provide active control of one or more of these or other vehicle motion parameters. In some cases, an active suspension system that delivers very comfortable decoupling control to small road inputs may perform poorly on large road events (e.g., hills, potholes, large steps, etc.) where the magnitude of the road event exceeds the suspension's ability to travel. In some cases, an active suspension system may be used to decouple the vehicle body from disturbances (e.g., skyhook control) so that the center of gravity of the vehicle body maintains a substantially constant or effectively substantially constant height despite the disturbance. Such vehicle control may cause the vehicle's wheels to reach their limits of travel (e.g., exceed their travel threshold) because the decoupling control uses a large amount of suspension travel to compensate for large road events. Reaching the limits of travel may result in noise or sudden force transfers on the vehicle body, which may be undesirable. Therefore, the inventors have recognized the need for vehicle body separation control that uses an active suspension system to adapt to existing road conditions in order to avoid reaching the limits of suspension travel. The inventors have further recognized the benefits of a robust vehicle body separation control methodology that works effectively on a wide range of road surfaces and a variety of road events in order to maintain user comfort while avoiding suspension system reach the limits of travel.

[0010]

[0016] In addition to the above, the inventors have recognized the difficulty of attempting to predict and compensate for future vehicle behavior, for example, when limited to non-predictive information. Conventional suspension systems may apply a constant control methodology that is effectively applicable to all conditions that may be encountered on a road network, while potentially reducing the overall performance of the suspension system. In contrast, the inventors of the present application have recognized the advantages of a control methodology that uses current information (e.g., limited to non-predictive information) to adapt to different road conditions to improve suspension performance. In particular, the inventors have recognized the advantages of providing improved vehicle-body isolation over a wide range of road conditions, for example, by using previously measured information about the road surface. For example, the inventors have recognized that a suspension system control methodology that works well to isolate small bumps may perform poorly when encountering, for example, a slope or incline. According to this example, a separation control module operating without predictive information may initially erroneously conclude that a slope is a small bump based on current information, ultimately resulting in a suspension response that is inappropriate for the slope (e.g., reaching the limit of travel, causing the vehicle body to tip over, etc.). The inventors have recognized this problem, and the systems and methods of the exemplary embodiments herein provide a technical solution to suspension control to improve separation control in various road conditions. However, it should be understood that the systems and methods disclosed herein are also contemplated when implemented in a vehicle assisted by predictive sensors during a current road journey or by information about the road ahead of the vehicle collected during a previous road journey.

[0011]

[0017] In view of the foregoing, the inventors have recognized the advantages of a vehicle control system that dynamically blends the vehicle body isolation and road following control outputs of the vehicle control system. On road surfaces with small road events (e.g., events that result in suspension responses that are less than limiting of travel), the blend may be biased toward vehicle body isolation control (e.g., skyhook control), which may increase occupant comfort by reducing or eliminating overall vehicle body movement due to vibrations imposed on the vehicle body by disturbances from various types of road events. On road surfaces with large road events (e.g., events that may result in suspension responses that are greater than limiting of travel), the blend may be biased toward vehicle tracking control (e.g., ground hook control). The road following control may aim to maintain the vehicle body at a height determined relative to the contours of the road surface. The road following control may prevent limiting of travel events within the active suspension. A blend between vehicle body separation control (e.g., skyhook) and road following control (e.g., ground hook) may result in a controller that may dynamically shift between stiff vehicle body separation control (e.g., "rigid skyhook"), where heavier vehicle body separation is preferred, and weak vehicle body separation control (e.g., "weak skyhook"), where heavier road following control is preferred. Such a vehicle control system may deliver firm comfort control over a range of road surfaces and may help avoid the occurrence of suspension driving event limitations without significantly reducing user comfort. Additionally, such a vehicle control system may be simple to implement and, in some embodiments, may not necessarily need to directly monitor the position of the suspension system relative to its range of motion to achieve a desired reduction in the number and / or severity of driving event limitations.

[0012]

[0018] In some embodiments, a vehicle may include a vehicle body, a plurality of wheels, and an active suspension system operably coupled to the plurality of wheels and the vehicle body. The active suspension system may include at least one actuator configured to apply an active force to at least one of the plurality of wheels in at least one mode of operation. The vehicle may include at least one processor configured to control the active suspension system, particularly the active forces and / or damping forces applied by the active suspension system between the wheels and the vehicle body to affect the response of the vehicle's chassis or body while driving along a road surface. In some embodiments, the at least one processor may operate a first suspension control module and a second suspension control module. The suspension control modules may be operated based on one or more inputs, the output of each suspension control module being a force command usable to command at least one actuator to apply an active force and / or damping force between the vehicle body and the wheels. The first suspension control module may be a separate control module and may provide the first force command based at least in part on an input including a vehicle body parameter (e.g., vehicle body speed). The first force command may thus be a force command intended to avoid vehicle body movement when the vehicle encounters a road feature (e.g., a bump, a pothole, etc.) that may result in vehicle body movement (e.g., skyhook control). The second suspension control module may be a tracking control module and may provide the second force command based at least in part on inputs including vehicle body parameters and / or suspension parameters (e.g., suspension speed). The second force command may thus be a force command intended to maintain the vehicle body in a fixed position (vertically) relative to the ground with limited isolation against disturbances (e.g., groundhook control or weak skyhook control).

[0013]

[0019] The inventors have recognized that multiple force commands (e.g., the first and second force commands described above) may be blended by at least one processor according to a blending ratio to generate a blended (e.g., third) force command that may be used to actuate at least one actuator of an active suspension system. In some embodiments, the blending ratio may be varied based on the output of the first suspension control module, e.g., to change the relative weighting of the first and second forces used to provide the blended (e.g., third) force. For example, a larger increase in the output of the first force controller module may be associated with a larger obstacle, such as a slope, rather than a smaller obstacle, such as a step; therefore, the blending ratio may be adjusted to weight the second force output from the second suspension control module more heavily to provide the blended force command. In this manner, a combination of separation control and ground tracking control may be dynamically and automatically utilized based on the output of the separation control module to increase overall separation performance while serving to avoid or eliminate undesirable events, such as reaching the limits of wheel travel (e.g., exceeding a threshold wheel travel).

[0014]

[0020] According to exemplary embodiments disclosed herein, an isolation control module (e.g., a first control module) may be tuned to provide a first level (e.g., maximum) of isolation of the vehicle chassis or body from road inputs. The control goal of the isolation control module may be to avoid vertical acceleration of the vehicle body relative to one or more vehicle body motion parameters (e.g., heave, pitch, roll, etc.). Such isolation control is sometimes known as "skyhook" control. Skyhook control may be implemented to keep the vehicle body flat while absorbing road inputs with suspension travel. In some implementations, this control strategy may work well for active suspension systems when sufficient suspension travel is present so that the force commands requested by the isolation control module are possible. However, as discussed above, during large road inputs, this type of control module may result in excessive suspension travel, leading to vulnerability in stopping impacts (e.g., wheels reaching the limits of suspension travel). In some embodiments, the suspension travel range for the vehicle may be ±7 cm (14 cm total end-to-end suspension travel). In other embodiments, any suspension travel range may be utilized for vehicles including travel ranges greater than or less than ±7 cm. The tracking control module (e.g., the second control module) may be configured to include some "ground hook control" to reduce the level of separation of road inputs to the vehicle body relative to the separation control module. In contrast, the ground hook control may serve to keep the vehicle body at a set distance from the underlying road surface. Thus, in some embodiments, the tracking control module may be configured to deliver a moderate level of vehicle body separation to road inputs, but with reduced suspension travel. In some embodiments, to avoid abrupt transitions in suspension control, the contribution of the ground hook control may be made less steep through the use of a non-linear gain curve. Additionally, in some embodiments, the tracking control module may provide more damping to rebound compared to compression.

[0015]

[0021] It should be noted that while the separation control module and the tracking control module may be described herein as implementing skyhook control or groundhook control, respectively, in some embodiments, the control modules may implement a mixture of skyhook control and groundhook control. In some such embodiments, the separation control module may be weighted more heavily towards skyhook control than towards groundhook control. In some embodiments, the tracking control module may be weighted more heavily towards groundhook control than towards skyhook control.

[0016]

[0022] To serve to implement relative weighting of the different suspension control modules, the inventors have recognized the advantage of a blending module that includes appropriate decision logic for blending the outputs of the separation and tracking control modules. The blending of the outputs of the two control modules may be determined, for example, by monitoring the magnitude and frequency characteristics of the separation control force. This methodology relies on the characteristic that the output of the separation control module is strongly correlated with suspension travel. If the output (e.g., force command) of the separation control module is small or of short duration, complete separation control may be implemented. However, if the output of the isolation control module (e.g., a force command) is large, long-term tracking control may be implemented according to a blending ratio. The blending ratio may be calculated automatically, for example, by a formula, based on information from the isolation control module and / or other inputs about the vehicle. In this manner, the overall control of the vehicle's active suspension may be modified in real time to adjust to isolate small road features (e.g., bumps, potholes, etc.) or compensate for large road features (e.g., slopes) while avoiding undesirable events that limit vehicle travel (e.g., exceeding a wheel travel threshold). Although the embodiments herein describe isolation control modules and tracking control modules, the methodologies described herein may be applicable to combining any multiple control module outputs. That is, the embodiments described herein may be applicable to a wide range of control module combinations related to various parameters.

[0017]

[0023] In some embodiments, a blend ratio may be utilized to represent the transition between the isolated control module and the tracking control module. In some embodiments, the blend ratio may be a value representing the contribution of the output from one or more control modules to the total force command. For example, the blend ratio may be the ratio of tracking control to isolated control, and in some embodiments, the blend ratio may be between 0 and 1. In such embodiments, 0 may indicate full isolated module control (e.g., the full force command output is equal to the force command output of the isolated control module), while 1 indicates full tracked module control (e.g., the full force command output is equal to the force command output of the tracking control module). Of course, different ranges for the blend ratio, both greater than and less than the blend ratios listed above, may also be used.

[0018]

[0024] In some embodiments, the blend ratio may be adjusted via a notch filter, a PI filter, and / or a dead zone parameter, as further described herein. Such modifiers may shape the desired sensitivity to components of different frequencies and magnitudes for different control modules. In some embodiments, the blend ratio may be utilized to generate a linear blend of the forces output by the tracking control module and the decoupling control module to generate the total force command. In some cases, this may generate a combined force signal that delivers a firm comfort mode on various road surfaces while reducing or minimizing the risk of driving events. In other embodiments, the blend ratio may be a nonlinear polynomial or represent another relationship to combine the outputs of the two controllers into a total output. For example, in some embodiments, the blend ratio may represent a weighting or scaling between the force commands of the two controllers to generate the total force command. The blend ratio value may vary linearly based on the first control module output, may vary nonlinearly based on the first control module output, and / or may vary based on another function of the first control module output.

[0019]

[0025] In some embodiments, the raw blend ratio may change rapidly because it is a function of the instantaneous separation force command. Therefore, the inventors have recognized the benefit of suppressing repeated cycling between full tracking control and full separation control with a hit / hold module. In some embodiments, the hit / hold module may set the blend ratio for a predetermined level for a threshold time when a threshold output from the first control module is detected. For example, the hit / hold module may set the blend ratio to provide a full tracking state (e.g., with zero contribution from the separation control module) at an appropriate time during a larger event (e.g., one second or longer). In some embodiments, the blend ratio may be further smoothed to avoid repeated cycling by implementing a low-pass filter. The low-pass filter may remove high-frequency components that may be undesirable to obtain a filtered blend ratio used to determine the overall blended force output.

[0020]

[0026] In some embodiments, outputs to the various control modules described herein may be provided by one or more sensors onboard the vehicle or from an onboard or remote database. In some cases, multiple and / or redundant sensors may be utilized to provide information (e.g., current and / or anticipated information) from which force commands may be determined by the control modules (e.g., via proportional control, integral control, and / or derivative control). Sensors may provide information related to different components of the vehicle, including, for example, wheels, suspension components, wheel body components, user interface components, transmission components, engine components, etc. In some embodiments, one or more accelerometers may be utilized to provide acceleration information about vehicle components. For example, accelerometers may be arranged on the vehicle body that may provide vehicle body acceleration information or vehicle body velocity information (e.g., via integral acceleration). In some embodiments, information from one or more accelerometers on the vehicle body may be utilized to determine the vehicle body's inertial heave, pitch, and roll rates, each of which are parameters that may be utilized for skyhook control. As another example, one or more accelerometers may be arranged on one or more components of the vehicle suspension and / or wheel assembly and configured to provide suspension acceleration information (e.g., in the direction of travel, such as vertically) and suspension velocity information (e.g., via integration of acceleration). In some embodiments, information from one or more accelerometers of the suspension may be utilized to determine suspension heave, pitch, and roll rates relative to the road surface, each of which are parameters that may be utilized for ground hook control. Other sensors, including encoders, potentiometers, and / or other suitable types of sensors in any suitable portion of the vehicle, may also be utilized to sense position, velocity, and / or acceleration information of relevant portions of the vehicle. In some embodiments, the suspension actuators may provide feedback information to the control module regarding their force output, position, velocity, and / or acceleration. In view of the above, any suitable inputs and sensors may be utilized as inputs for the controllers described herein, as the disclosure is not so limited.

[0021]

[0027] In some embodiments, the control module described herein may be a vehicle-level control module. That is, the control module may output an overall force command to the suspension system for execution. The suspension may include one or more actuators, and this overall force command may be assigned to individual actuators to achieve the overall force command and the desired overall response of the vehicle body. In some embodiments, the methodology described herein may be applicable to control of a vehicle on a per-angle or per-actuator level following the blending process described in accordance with exemplary embodiments herein. In response to the described vehicle-level control, in some embodiments, the input to the control module described herein may also be vehicle-level. For example, in some embodiments, information from individual sensors (e.g., associated with individual wheels or actuators) may be combined with information from other sensors to provide overall information regarding the movement of the entire vehicle body or entire vehicle suspension system. For example, an individual input for the suspension system associated with a single wheel may be averaged with other wheels of the vehicle to obtain an averaged per-angle input provided to the vehicle-level controller. Any suitable method of combining information from multiple sensors may be utilized to obtain the overall information provided to the control module, including, but not limited to, summing, averaging, or other matrix multiplication methods. According to some embodiments herein, a control methodology including a mixed ratio may be implemented to control the heave and / or pitch of a vehicle body. In some embodiments, a total force command may be configured to modify the heave and / or pitch motion of the vehicle body, and the total force command may be allocated to individual actuators to achieve an overall control objective. In other embodiments, the control methodology described herein may be utilized to control other vehicle motion parameters, such as the roll of the vehicle body, as the disclosure is not so limited.

[0022]

[0028] In some embodiments, a vehicle may include a user interface through which a user may provide user input to affect control of the vehicle. For example, the user interface may include a touchscreen, buttons, switches, a microphone (e.g., for receiving voice commands), etc. In some embodiments, the user interface may be configured to receive input from a user, which may be utilized to update one or more parameters for control of the vehicle. For example, in some embodiments, the user interface may be configured to receive user input. The mixture ratio may then be determined at least in part using the user input as discussed herein. According to such an example, a user may provide input for an operating mode selection (e.g., comfort, sport, etc.). Based on the mode selection, the mixture ratio determination may change. In a comfort mode, for example, the mixture ratio determination may be set to more favorably a separation control mode to increase vehicle body separation. In a sport mode, for example, the mixture ratio determination may be set to more favorably a tracking control mode to introduce increased movement into the vehicle body to more closely track changes in road height to increase driving feedback, e.g., a more sports car feel. In some cases, the formula for determining the mixture ratio may be updated, and / or one or more parameters in the formula for determining the mixture ratio may be updated based on received user input. In some embodiments, the formula for determining the mixture ratio may be updated, and / or one or more parameters in the formula for determining the mixture ratio may be updated based on information from the identity of a user and / or the vehicle driver and / or occupant. For example, an occupant may be prone to motion sickness, so the formula is updated when the occupant is identified as preferring a control strategy that avoids vehicle body movements associated with motion sickness. In some embodiments, the vehicle control system may determine the identity of a driver or occupant by detecting credentials (e.g., key, phone, RFID, etc.) associated with the particular driver or occupant.In some embodiments, the driver or passenger may identify themselves (e.g., via user input in a graphical user interface). In some embodiments, the driver or passenger may be identified by detecting a living body via a biometric sensor (e.g., facial recognition via a camera, fingerprint via a fingerprint sensor, etc.). In some embodiments, other methods of identifying the driver and / or passenger may also be implemented.

[0023]

[0029] Alternatively or additionally, in some embodiments, the vehicle may include at least one predictive sensor. The at least one predictive sensor may be configured to acquire predictive information about upcoming road conditions, road events, or road features. In some embodiments, the at least one predictive sensor may include one or more LIDAR sensors, cameras, radar sensors, ultrasonic sensors, terrain-based navigation systems, and / or any other suitable predictive sensors. In some embodiments, the blending ratio may be determined based on the predictive information acquired by the predictive sensor. For example, the predictive information may indicate small road features (e.g., bumps or potholes) that can be fully complemented by the decoupling control module. According to this example, the blending ratio may be determined to favor the decoupling control module. Alternatively, the predictive information may indicate large road features (e.g., slopes) that cannot be fully complemented by the decoupling control module. According to this example, the blending ratio may be determined to incorporate additional output into the total output (e.g., force command) from the tracking control module. In this manner, predictive information may optionally be incorporated into the methodology described herein to improve the amount of vehicle body separation that can be provided, while still adapting to changes in road conditions that cannot be fully compensated for by the separation control module.

[0024]

[0030] According to exemplary embodiments herein, "skyhook" may refer to control that attempts to isolate a vehicle body from external disturbances, regardless of the contours of the underlying road surface. For example, under complete or virtually complete skyhook control, the vehicle body may not or may not accelerate in roll, pitch, and / or heave. It should be understood that when skyhook control is implemented by an actual active suspension system, depending on the magnitude and frequency of the road input to the vehicle from the corresponding characteristics of the road surface, the active suspension system may only cushion a portion of the road input such that the vehicle body still experiences some force / acceleration due to the road input. However, this force / acceleration may be reduced compared to a situation in which skyhook control is not applied.

[0025]

[0031] According to exemplary embodiments herein, "ground hook" may refer to a control that attempts to maintain a fixed or virtually fixed distance between the vehicle body and the underlying road surface. For example, the distance between the wheels and the vehicle body under full ground hook control may be maintained constant. It should be understood that when ground hook control is implemented by an actual active suspension system, depending on the magnitude and frequency of road inputs to the vehicle from corresponding features on the road surface, the active suspension system may not maintain a constant distance between the vehicle body and the road surface. Instead, it may experience some variation from the target distance, but these variations from the target distance may be mitigated compared to a situation in which ground hook control is not applied.

[0026]

[0032] Variations of skyhook and groundhook may be implemented in some embodiments. For example, “rigid” may refer to a control module that tends more toward its full form of control objective, while “weak” may refer to a controller that tends more toward other forms of control less fully. For example, a “rigid skyhook” controller may attempt to implement as full skyhook control as possible for a given active suspension system (e.g., providing the highest level of vehicle body isolation for the active suspension system). In some embodiments, a “rigid skyhook” may implement skyhook control at frequencies as low as 0.2 Hz. Alternatively, a “weak skyhook” controller may implement some skyhook control, but also some groundhook control. In some embodiments, a “weak skyhook” may implement skyhook control at frequencies as low as 1 Hz, with a lower gain than the “skyhook” controller frequency. In some embodiments, the tracking control module may be a weak skyhook controller, implementing some groundhook control while maintaining some vehicle body isolation. Skyhook and groundhook control, and variations thereof, may be implemented in some embodiments to control at least a portion of the vehicle's heave and / or pitch. In some embodiments, the skyhook and groundhook controls may similarly control at least a portion of the roll of the vehicle.

[0027]

[0033] According to embodiments herein, a vehicle may include a vehicle body and one or more wheels (e.g., four wheels) supporting the vehicle body. The vehicle may include an active suspension system operably sandwiched between the one or more wheels and the vehicle body. The active suspension system may be configured to adjust the general force between one or more wheels of the vehicle and the ground (e.g., via tires) by applying a force between the wheels and the chassis or body of the vehicle. The active suspension system, in some embodiments, may be configured to generate extension or compression of a primary spring of a suspension assembly. The force applied between the wheels and the vehicle body may be transmitted to the vehicle body through the active suspension system, and the active suspension system may control one or more parameters of the vehicle body. Vehicle motion parameters may include, but are not limited to, rotation about various axes (e.g., roll and pitch). Vehicle motion parameters may also include, but are not limited to, movement along various axes (e.g., movement along a vertical z-axis, otherwise known as "heave"). In some embodiments, three Cartesian principal axes may be established with respect to a supporting surface (e.g., a plane) below the vehicle. In some embodiments, the three Cartesian principal axes may be established in the direction of local gravity when the vehicle is aligned with the ground. As discussed further below, the active suspension system may control one or more vehicle motion parameters of the vehicle's vehicle body by applying active or passive forces between the vehicle body and one or more wheels. Varying the forces output by the active suspension system may alter one or more vehicle motion parameters. In some embodiments, the vehicle may include at least one processor configured to execute computer-readable instructions stored in associated volatile or non-volatile memory that, when executed, perform any of the methods disclosed herein. In some embodiments, the at least one processor may be configured to control the active suspension system to control one or more vehicle motion parameters of the vehicle body. In some embodiments, the at least one processor may be operated as part of one or more control modules of the vehicle.

[0028]

[0034] In some embodiments, an active suspension system is operably sandwiched between one or more wheels and the vehicle body of the vehicle. The active suspension system may include one or more actuators associated with one or more wheels. For example, the active suspension system may include at least one actuator for each wheel of the vehicle. In some embodiments, the actuator of the active suspension system includes a hydraulic device operably coupled to an electric motor / generator. The term hydraulic device may refer to either a hydraulic motor or a hydraulic pump, where the hydraulic motor operates as a pump and / or the hydraulic pump operates as a hydraulic motor. The hydraulic device may be capable of providing fixed displacement, variable displacement, fixed speed, and / or variable speed, as this disclosure is not limited to any particular device. Suitable types of hydraulic devices may include, but are not limited to, gerotor pumps, vane pumps, gear pumps, screw pumps, and / or any other suitable type of hydraulic device. The term electric motor / generator may refer to either an electric motor and / or a generator. In either case, in some embodiments, the associated hydraulic device may drive the electric motor / generator to damp the hydraulic actuator while also functioning as a generator that generates electrical energy in at least one mode of operation. The electric motor / generator may also drive the hydraulic device as a pump that generates fluid flow to drive the actuator operation and / or resist movement of the actuator piston in at least one mode of operation. Depending on the particular embodiment, the electric motor / generator may operate as a generator only, a drive motor only, and / or both depending on the particular application. Suitable types of electric motor / generators may include, but are not limited to, brushless DC motors, brushed DC motors, induction motors, dynamos, or any other type of device capable of converting electricity into rotational motion and / or vice versa. The actuator may be configured to apply active and / or passive forces (which may also be referred to herein as damping forces) between the vehicle wheels and the vehicle chassis or body. Applying active and / or passive forces may be utilized to control movement of the vehicle body and / or wheels.In some embodiments, the active suspension system may include one or more physical springs or dampers, which may apply a passive force to one or more wheels and the chassis or body of the vehicle.

[0029]

[0035] Although the actuators of the active suspension systems disclosed above are described as including hydraulic devices and electric motors / generators, the present disclosure is not limited to any particular type of active suspension system. Accordingly, other suitable types of active suspension systems including different types of actuators may also be used. For example, electric actuators, such as solenoid-based actuators, actuators using linear electric motors, hydraulic actuators associated with a central pressure source (e.g., a pump) and associated with a valve, and / or any other suitable type of actuator that can be used to operate an active suspension system, may be used with the various embodiments disclosed herein, as the disclosure is not so limited.

[0030]

[0036] As used herein, an "active force" is a force generated by a vehicle suspension system and directed at least in part in the direction of movement at the point of application of the force on an associated structure. For example, an active force may include applying a force to a wheel in the direction of wheel movement via an actuator of the active suspension system. As used herein, a "passive force," "damping force," or other similar term may refer to a force that may be applied to a structure in a direction at least partially opposite to the movement at the point of application of the force. For example, while an actuator of a suspension system may generate a damping force in response to a wheel moving due to road features (e.g., a force that resists movement of the wheel and / or vehicle body), it should be noted that an active suspension system may also apply a damping force that resists movement of an associated mass. For example, in some embodiments, an actuator may apply a damping force in a direction at least partially opposite to the direction of movement of the damped component. According to exemplary embodiments described herein, a particular vehicle system (e.g., an active suspension system) may apply active and / or passive forces depending on the operating mode of the vehicle system. For example, an active suspension system may be operated in a first mode in which actuators are utilized to apply active forces to one or more portions of the vehicle (e.g., the vehicle body and vehicle wheels), and in a second mode in which only passive forces are applied in response to external force inputs on the vehicle. In some operating modes, a vehicle system including an active suspension system may generate both active and passive forces.

[0031]

[0037] As used herein, a "road event" is any event that may occur while a vehicle is traveling on a roadway. In some embodiments, a road event may include encountering a road feature. A "road feature" is any non-nominal road condition that a vehicle may encounter while traveling on a road surface. For example, road features may include, but are not limited to, rough pavement, potholes, manhole covers, drainage ditches, bumps, uneven lanes, variable road materials (e.g., mud, gravel, pavement, concrete, metal, etc.), road coverings (e.g., snow, ice, salt, sand, mud, water, etc.), and / or any other suitable feature that may contribute to a change in the forces applied to a vehicle traversing a road surface. In some embodiments, a road event may include a turn (e.g., traversing a corner). In some embodiments, a road event may include a braking event. A braking event is any instance or time when one or more brakes of a vehicle are applied, for example, to slow or stop the vehicle, or the vehicle is slowed by applying a drag force to one or more rotating components in the drive. A braking event may have any duration as the disclosure is not so limited, hi some embodiments, a braking event may include a single application of the brakes or multiple applications of the brakes as the disclosure is not so limited.

[0032]

[0038] According to example embodiments described herein, a vehicle control system, control module, or other suitable system may be operated by one or more processors. The one or more processors may be configured to execute computer-readable instructions stored in volatile or non-volatile memory. The one or more processors may be in communication with one or more actuators associated with various systems of the vehicle (e.g., braking system, active suspension system, steering system, rear steering system, driver assistance system, etc.) to control the operation and movement of the various systems of the vehicle. The one or more processors may receive information from one or more sensors that provide feedback about the various systems of the vehicle. For example, the one or more processors may receive position information about the vehicle from a Global Navigation Satellite System (GNSS) or other positioning system. The sensors on the vehicle may include, but are not limited to, wheel rotation speed sensors, accelerometers, inertial measurement units (IMUs), optical sensors (e.g., cameras, LIDAR), radar, suspension position sensors, gyroscopes, and / or any other suitable type of sensor. In this manner, the vehicle control system may implement proportional control, integral control, derivative control, combinations thereof (e.g., PID control), or other control strategies for various systems of the vehicle. Other feedback or feedforward control schemes are also contemplated, and the disclosure is not limited in this respect. Any suitable sensors in any desired quantity may be utilized to provide feedback information to one or more processors. Information from the sensors may be utilized in conjunction with desired processing techniques (e.g., machine vision). The one or more processors may also communicate with other controllers, computers, and / or processors over a local area network, a controller area network (CAN), a wide area network, a cloud-based database, or the Internet using suitable wireless or wired communication protocols. While the exemplary embodiments described herein are described with reference to a single processor, any suitable number of processors may be utilized as part of a vehicle, as the disclosure is not so limited.

[0033]

[0039] It should be understood that, as used herein, a vehicle body may refer to any suitable type of vehicle body structure, including, but not limited to, a unitary, unibody, or monocoque vehicle body structure, a vehicle body including a separately formed vehicle chassis attached to other portions of the vehicle body, and / or any other suitable type of vehicle body structure that functions as a sprung mass attached to the vehicle's suspension system. Additionally, it should be understood that references to a vehicle body disclosed herein may be interchanged with a vehicle chassis, and where the context permits, references to the operating parameters and physical characteristics of the vehicle body and vehicle chassis may be used interchangeably in any embodiment disclosed herein as the disclosure is not so limited.

[0034]

[0040] With reference to the figures, certain non-limiting embodiments are described in further detail. It should be understood that the various systems, components, features, and methods described with respect to these embodiments may be used individually and / or in any desired combination, as the disclosure is not limited to only the specific embodiments described herein.

[0035]

[0041] FIG. 1 is a schematic diagram of one embodiment of a vehicle 100. The vehicle includes a vehicle body 102 that supports various components of the vehicle. The vehicle 100 includes a first wheel 106A and a second wheel 106B operably coupled to the vehicle body 102. The first wheel 106A and the second wheel 106B may be coupled to a propulsion system (e.g., an internal combustion engine, an electric motor, etc.). The vehicle body 102 may represent the sprung mass of the vehicle bouncing off the first wheel 106A and the second wheel 106B. The first wheel 106A and the second wheel 106B may be two unsprung masses of the vehicle. While two wheels are shown in the embodiment of FIG. 1, in some embodiments, the wheels may include two, three, four, five, six, or other numbers of wheels, as the disclosure is not so limited. The vehicle of FIG. 1 has a center of mass 104, which may represent a central point about which the vehicle body 102 may rotate (eg, pitch, roll, and yaw).

[0036]

[0042] As shown in FIG. 1 , the vehicle 100 includes a vehicle control system 200 that may communicate with various subsystems via a communication system 201. As shown in FIG. 1 , the vehicle 100 includes an active suspension system 107 operably sandwiched between a first wheel 106A and a second wheel 106B (e.g., unsprung mass) of the vehicle and a vehicle body 102 (e.g., sprung mass). In some embodiments, the first wheel 106A and the second wheel 106B may represent a wheel assembly. For example, in some cases, the active suspension system 107 may be coupled to a wheel assembly or other intermediate component rather than being directly coupled to the wheels. As shown in FIG. 1 , the active suspension system 107 includes one or more active suspension actuators 108A, 108B that may be operably sandwiched between each wheel 106A, 106B of the vehicle and the vehicle body, such that separate actuators of the active suspension may independently control the movement of individual wheels of the vehicle. 1, a first actuator 108A is coupled to the first wheel 106A, and a second actuator 108B is coupled to the second wheel 106B. The actuators 108A, 108B may be configured to apply forces between the vehicle 106A, 106B and the vehicle body 102 to adjust the general components of the forces between the wheels and the road surface 300 by applying active expansion or compression forces intervening between the wheel or wheel assembly and the vehicle body. Such application of forces by the actuators 108A, 108B may affect the motion response of the vehicle body 102, and in particular one or more vehicle motion parameters.

[0037]

[0043] As shown in the embodiment of Figure 1, the vehicle 100 may also include a braking system including a first brake 110A and a second brake 110B. The first brake 110A may be coupled to the first wheel 106A, and the second brake 110B may be coupled to the second wheel 106B. In the embodiment of Figure 1, the braking system includes independent brakes coupled to each of the wheels 106A, 106B such that braking force may be applied to each wheel independently.

[0038]

[0044] As shown in FIG. 1 , a vehicle may traverse over a road surface 300. The road surface 300 may include one or more road features 302. The road features 302 may vary the normal load on the wheels 106A and / or 106B of the vehicle 100 as the wheels traverse over the road feature (e.g., by accelerating the wheels upward and / or downward). In some embodiments, the road features 302 may generate a vehicle body motion response of the vehicle based on one or more vehicle motion parameters of the vehicle body 102. For example, the road features 302 may induce roll, pitch, heave, or twist motion of the vehicle body 102 that may be perceptible to a user of the vehicle 100. The vehicle control system 200 may control the forces applied by the active suspension system 107 and each of the actuators 108A, 108B to provide a desired vehicle motion response characterized by one or more vehicle motion parameters (e.g., heave, pitch, roll, etc.). As discussed further below, the force commands may be assigned to different actuators 108A, 108B of the active suspension system 107 to provide a desired level of isolation of the vehicle body 102 from obstacles to improve user comfort and / or properly track the road surface.

[0039]

[0045] According to the embodiment of FIG. 1 , the vehicle wheels 106A, 106B may have a range of motion 112A, 112B relative to the vehicle body 102 provided by the active suspension system 107. That is, the wheels 106A, 106B may be able to move a certain distance to compensate for or mitigate the effects of disturbances caused by road features 302. At the end of the range of motion 112A, 112B, the suspension system may reach an end stop of the vehicle body 102 that stops the wheel from moving further in its current direction of motion. Contacting the end stop may be undesirable in most situations, as forces and resulting vibrations may be transmitted directly between the wheels 106A, 106B and the vehicle body 102 without being dampened by the active suspension system 107. In some embodiments, the end stop may have some shock absorption, but this absorption may be limited. Thus, as previously discussed, the inventors have recognized the advantages of an active suspension system 107 that may utilize the range of motion 112A, 112B of the wheels 106A, 106B to separate the vehicle body 102, while avoiding limitations in wheel running events that may be disruptive to vehicle occupants. Such exemplary active suspension systems and related methods are discussed further below. In some other embodiments, the range of motion 112A, 112B may not be a physical range of motion, but rather a range of motion enforced by limits set by the vehicle control system 200.

[0040]

[0046] It should be noted that the vehicle in FIG. 1 is simplified for illustrative purposes. The vehicle 100 may include any number of systems that affect the vehicle's dynamics and response to obstacles from road features 302. User input devices, such as steering, throttle, and brakes, may affect the vehicle's response based on user input. A vehicle control system may include at least one processor configured to execute computer-readable instructions and control one or more vehicle outputs. For example, the vehicle control system 200 may include at least one processor configured to receive input from a user and command one or more systems of the vehicle to take a particular action (e.g., accelerate, decelerate, steer). In some embodiments, the vehicle control system 200 may include an electronic stability control system and an anti-lock braking system (ABS). The electronic stability control system may be configured to automatically apply brakes 110A, 110B when traction is lost to help steer the vehicle toward the driver's intended destination. The ABS is configured to prevent the wheels from locking and skidding. Vehicle control system 200 may receive multiple inputs from a variety of sources, including, but not limited to, user input, sensors attached to the vehicle's sprung mass, sensors attached to the vehicle's unsprung mass, feedback from one or more actuators, data from a local or remote database, or any combination of the foregoing. Vehicle control system 200 may utilize the multiple inputs to determine one or more outputs (e.g., force commands) to one or more systems of the vehicle (e.g., active suspension system 107, brakes 110A, 110B, throttle, etc.) to achieve a desired vehicle response. Exemplary operating modes and control schemes for vehicle control system 200 are further discussed below.

[0041]

[0047] In some embodiments, such as that shown in FIG. 1 , vehicle 100 may include a real-time communication system 201 capable of communicating between various subsystems and vehicle outputs. Communication system 201 may utilize any suitable connection protocol, including, for example, a controller area network (CAN), a local interconnect network (LIN), a vehicle area network (VAN), FlexRay, D2B, Ethernet, direct communication links (such as wired and fiber optic), or wireless communication links. The communication system may be utilized to share information between subsystems, such as ABS or ESC, while also receiving vehicle state parameters or other information from these or other systems. Information shared between subsystems and that may be utilized for vehicle output control includes, but is not limited to, vehicle yaw and yaw rate, vehicle speed, vehicle acceleration, vehicle lateral acceleration, steering wheel position, steering wheel torque, suspension spring compression or expansion when braking, vehicle body heave velocity, and vehicle heave velocity (e.g., suspension speed). The vehicle control system 200 may control the active suspension system 107 based on information from the vehicle, such as the status of one or more vehicle subsystems, such as ABS and ESC, that are engaged during an unusual event. For example, the system may provide different control of the wheels and vehicle when one or more systems are engaged.

[0042]

[0048] In some embodiments, the active suspension system 107 may sense several parameters about the road, wheels, vehicle body motion, and other parameters that may benefit other vehicle subsystems. Such information may be transmitted from the active suspension system to the vehicle control system 200 and other subsystems via the communication system 201. The other vehicle subsystems may alter their control based on information from the active suspension system. As a result, bidirectional information may be communicated between the active suspension system 107 and the other subsystems, and control of both the active suspension system and other vehicle systems may be provided based at least in part on this information transfer. In some embodiments, the communication system 201 may include a transceiver configured to transmit or receive information. In some embodiments, the transceiver may be configured to receive reference road information from another vehicle or a cloud service (e.g., one or more servers). The transceiver may be configured to communicate wirelessly via any suitable wireless protocol, as the disclosure is not so limited.

[0043]

[0049] In some embodiments, vehicle control system 200 may include predictive sensors 116. The predictive sensors may sense road characteristics, road features, or objects in front of vehicle 100, which may be provided to the vehicle control system (e.g., at least one processor of the vehicle control system) as predictive road information. In some embodiments, predictive sensors 116 may include one or more of a LIDAR sensor, a camera, a radar sensor, an ultrasonic sensor, or any other suitable predictive sensor. In some embodiments, the predictive information obtained by the predictive sensors may be provided to a processor used to control the vehicle (e.g., determine the mixture ratio). In the embodiment of FIG. 1, the vehicle control system may also include reference road information, which may be stored in a memory onboard the vehicle. In some embodiments, the predictive information may be utilized in controlling vehicle 100, for example, to reduce or eliminate undesirable movement of vehicle body 102.

[0044]

[0050] In some embodiments, the vehicle may include a user interface 118 through which a user may provide user input to affect control of the vehicle. In the embodiment of FIG. 1, the user interface 118 may include a touchscreen of the infotainment unit. In other embodiments, the user interface may include a touchscreen, a steering wheel, buttons, switches, a microphone (e.g., for voice commands), pedals, or any other suitable input device. The user interface 118 may be configured to receive input from a user, which may be used to update one or more parameters for control of various subsystems of the vehicle, including the active suspension system. In some embodiments, the user may provide user input to the user interface 118 to select an operating mode (e.g., comfort, sport, etc.). Based on the selected mode, various control parameters of the vehicle may be changed, including, but not limited to, engine tuning, throttle response, braking response, steering response, and suspension control. For example, the user input may be used to update parameters that affect the determination of forces applied by the actuators 108A, 108B of the active suspension system 107.

[0045]

[0051] In some embodiments, vehicle control system 200 is configured to control various vehicle subsystems, including active suspension system 107. As discussed further below, particularly with reference to FIGS. 2-4 , vehicle control system 200 may be configured to determine force commands for actuators 108A, 108B of the active suspension system to control vehicle motion parameters of vehicle body 102. For example, vehicle control system 200 may command actuators 108A, 108B to generate forces and / or movements of wheels 106A, 106B to achieve a desired movement or separation of vehicle body 102 that is perceptible to a vehicle occupant. In one mode of operation, vehicle control system 200 commands actuators 108A, 108B to isolate the vehicle body from acceleration caused by a disturbance (e.g., caused by road feature 302). In such an operating mode, the wheels 106A, 106B may move relative to the vehicle body 102 within their respective ranges of motion 112A, 112B to compensate for at least a portion of the forces caused by the road feature 302 or due to inertial forces induced by vehicle acceleration. In some embodiments, the vehicle control system 200 may include one or more controllers that may result in a total force command used to command the actuators 108A, 108B. Exemplary individual controllers and their effect on controlling the motion parameters of the vehicle body 102 are further discussed with reference to FIGS. 2-3. Combining or blending multiple controller outputs and their combined effect on controlling the motion parameters of the vehicle body are further discussed with reference to FIG. 4.

[0046]

[0052] FIG. 2 is a schematic diagram of an embodiment of a vehicle 100 under vehicle body isolation control. In the embodiment of FIG. 2, the vehicle control system implements an isolation control module that may seek to achieve rigid skyhook control. That is, the vehicle control system attempts to avoid, minimize, or effectively eliminate acceleration of the vehicle body 102 due to one or more motion parameters (e.g., pitch, roll, and / or heave). For example, in the vertical heave direction, the vehicle control system, in certain modes, may attempt to maintain the vehicle's center of mass 104 in a horizontal plane as the vehicle travels along the road surface. As illustrated in FIG. 2, isolation control line 114A represents the vehicle control system's goal in controlling the heave motion parameter of the vehicle body 102 as the vehicle moves along the road surface 300. The isolation control line 114A is horizontal to the page so that the vehicle body 102 does not move up or down (e.g., in the heave direction) in response to road features. While the isolation control line 114A may represent the vehicle body's heave motion parameter, the vehicle control system may control other motion parameters as well. For example, vehicle body pitch (e.g., clockwise or counterclockwise rotation about the center of mass 104 relative to the page) may also have the goal of remaining constant, actually constant, or substantially constant under rigid skyhook control.

[0047]

[0053] As shown in FIG. 2 , the vehicle includes a first wheel 106A and a second wheel 106B that support the vehicle body 102 (and other sprung masses) on a road surface 300. The first wheel 106A and the second wheel 106B may be coupled to the vehicle body 102 via an active suspension system (see, e.g., FIG. 1 ). The first wheel 106A may be movable within a first range of motion 112A relative to the vehicle body 102. The position of the first wheel 106A within the first range of motion 112A may be controlled by, for example, passive and active components, including actuators and springs. In particular, the first wheel 106A may be controlled via an actuator of the active suspension system that may apply a force to the first wheel 106A to achieve a desired position of the first wheel relative to the vehicle body 102. The actuator applies a force between the vehicle body 102 and the first wheel 106A to achieve the desired position, and may also apply a force to the vehicle body to control the motion of the vehicle body. Similarly, the second wheel 106B may be movable relative to the vehicle body 102 within a second range of motion 112B. The position of the second wheel 106B within the second range of motion 112B may be controlled by passive and active components, including actuators and springs. In particular, the second wheel 106B may be controlled via an actuator of an active suspension system, which may apply a force to the second wheel 106B to achieve a desired position of the second wheel relative to the vehicle body 102. The actuator applies a force between the vehicle body 102 and the second wheel 106B to achieve the desired position, and may also apply a force to the vehicle body to control the motion of the vehicle body.

[0048]

[0054] According to the example of FIG. 2 , the road surface 300 includes multiple road features 302A, 302B, 302C, and 302D. These road features represent bumps or variations in an otherwise smooth, virtually smooth, or nominally smooth road surface that impart forces to the vehicle 100 when the first wheel 106A and the second wheel 106B contact them. In a conventional vehicle suspension, springs and dampers would cushion or delay the forces transmitted to the vehicle body 102. However, a completely passive suspension would transmit some forces to the vehicle body 102, causing the center of mass 104 to deviate from the idealized separation control line 114A. In an active suspension system, active forces that oppose the forces imparted by the wheels to the road features 302A, 302B, 302C, and 302D could reduce or eliminate the forces imparted to the vehicle body 102 that would cause it to deviate from the idealized separation control line 114A. For example, when the first wheel 106A encompasses a first road feature, rather than maintaining a fixed distance between the first wheel and the vehicle body 102, the active suspension system may reduce the distance between the first wheel and the vehicle body (e.g., move the wheel upward) to compensate for the increased height of the first road feature. However, as discussed above, the ability of the active suspension system to compensate for a road feature depends at least in part on the range of motion of the vehicle's wheels and the size and length of the particular road feature. For example, road features smaller than the range of motion of the wheels may be compensated for by the active suspension system, whereas larger road features that exceed the range of motion of the wheels may not be compensated for by the active suspension. Additionally, such road features may result in limiting driving events (e.g., collision with an end stop). Alternatively, road features with lengths less than the threshold length and corresponding threshold time between crossings may be compensated for by the active suspension without impairing the ability of the suspension to compensate for future road features, whereas road features with lengths greater than the threshold length or time may be compensated for (depending on magnitude as described above) but may impair the ability of the active suspension system to compensate for future road features or may otherwise affect the dynamics of the vehicle. The length of the road feature may also correspond to the frequency of forces applied to the vehicle.For example, a hill may result in lower frequency applied forces compared to the higher frequency forces of a pothole (at the same forward speed), which may be compensated for differently by the vehicle control system and active suspension system as disclosed herein.

[0049]

[0055] As shown in FIG. 2 , the road surface 300 includes four road features 302A, 302B, 302C, and 302D. The first road feature 302A has a first magnitude M1 and a first length L1. In some embodiments, the magnitude of the road feature may be measured in vertical displacement from the intermediate road surface (e.g., horizontal). In the example of FIG. 2 , the first magnitude M1 is smaller than the first range of motion 112A and the second range of motion 112B of the first wheel 106A and the second vehicle 106B, respectively. Thus, the vehicle control system of the vehicle 100 may be able to complement the effect of the first road feature 302A on the vehicle body and substantially maintain the separation control line 114A. The first length L1 is also shorter than a threshold length or time that may indicate a temporary road feature such as a bump, crack, pothole, or the like, compared to larger road features such as a slope. Thus, the vehicle's active suspension system may be able to control the suspension as the vehicle traverses road features to maintain the separation control line 114A and return the wheels 106A, 106B to their original positions once the first road feature is removed. Similar to the first road feature 302A, the second road feature 302B has a second magnitude M2 ​​that is smaller than the range of motion 112A, 112B of the wheels 106A, 106B. The second road feature's second length L2 is also smaller than a threshold length or time. The third road feature 302C has the same size and length as the first road feature 302A. The fourth road feature 302D has the same size and length as the first road feature 302A. Thus, the vehicle 100 may traverse multiple road features while maintaining or substantially maintaining the separation control line 114A while avoiding the limits of a driving event. Thus, in an environment such as FIG. 2, isolation control implementing rigid skyhook control may be sufficient or may be sufficient to completely isolate the vehicle body 102 from external disturbances, or at least to the extent that it can be physically isolated using an active suspension system.

[0050]

[0056] FIG. 3 is a schematic diagram of an embodiment of the vehicle 100 under road-following control, representing a different scenario from that of FIG. 2. In the scenario of FIG. 3, the road surface 300 includes a fifth road feature 302E. The fifth road feature 302E may represent a slope or other large road feature. The fifth road feature includes a third magnitude M3 that is greater than the respective ranges of motion 112A, 112B of the first wheel 106A and / or the second wheel 106B. Therefore, the separation control shown and described with reference to FIG. 2 may not work in the scenario of FIG. 3 because attempting to compensate for the fifth road feature 302E may cause the first wheel 106A and the second wheel 106B to reach the limits of their travel (e.g., contact an end stop). As shown in FIG. 3, the fifth road feature 302E also includes a third length L3 that is longer than a threshold length or time. Therefore, the force generated by the vehicle interacting with the fifth road feature may be at a lower frequency than that of FIG. 2. In some embodiments, the threshold length may be a vehicle traverse length for a threshold time length greater than about 1 second (e.g., a frequency less than 1 Hz), although other times and / or frequencies shorter or longer than this range are contemplated as the disclosure is not so limited.

[0051]

[0057] In the embodiment of FIG. 3, the vehicle 100 may utilize a tracking control module that implements rigid ground hook control. In rigid ground hook control, the vehicle's center of mass 104 may be controlled to maintain a fixed distance between the vehicle's body and the road surface 300, at least as much as can be physically imposed by the active suspension system. In this manner, forces generated by a disturbance, such as the fifth road feature 302E, may be transferred to the vehicle body 102 via the first wheel 106A and the second wheel 106B. An exemplary tracking control line 114B is shown in FIG. 3 and illustrates the path of the center of mass 104 as the vehicle traverses the road surface 300. As shown in FIG. 3, the tracking control line 114B is a mirror image of the fifth road feature 302E. Under the tracking control of FIG. 3, the first wheel 106A may be maintained at the center point (or other predetermined point) of its range of motion 112A. Similarly, the second wheel 106B may be maintained at the center point (or other predetermined point) of its range of motion 112B. Thus, the first wheel 106A and the second wheel 106B may avoid contact with the end stops under tracking control, as shown in FIG. 3. It should be noted that FIG. 3 demonstrates rigid ground hook control for illustrative purposes. In other embodiments, the vehicle may not implement rigid ground hook control because force transfer from the road surface 300 to the vehicle body 102 may be undesirable. In such other embodiments, a weak ground hook may be utilized, but may provide some compensation for obstacles (e.g., by allowing the wheel travel to at least partially absorb the obstacle).

[0052]

[0058] As discussed above, the present inventors have recognized the advantages of a vehicle control system that dynamically blends the isolation control shown in FIG. 2 with tracking control as shown in FIG. 3. Such a vehicle control system may utilize isolation control, as illustrated in FIG. 2, to at least partially or completely isolate the vehicle body from road features that are smaller and / or longer than a predetermined threshold (e.g., wheel range of motion, or threshold length or time). However, when road features such as fifth road feature 302E in FIG. 3 are involved, the vehicle control system may be able to avoid limitations of driving events if the isolation control module may not be used exclusively in all circumstances. The results of such an exemplary blending process are illustrated in FIG. 4.

[0053]

[0059] FIG. 4 is a schematic diagram of an embodiment of a vehicle 100 under mixed vehicle-body separation and road-following control. As shown in FIG. 4, the scenario is similar to that of FIG. 3. That is, the road surface 300 includes a fifth road feature 302E having a third magnitude M3 and a third length L3. The magnitude M3 exceeds the respective ranges of motion 112A, 112B of the wheels 106A, 106B. Two previous control strategies are also shown in FIG. 4 for comparison of objectives. A separation control line 114A is shown, which would cause the wheels 106A, 106B to reach the limit of travel, resulting in a sudden injury to the vehicle body 102 and preventing the vehicle from following the desired path. A tracking control line 114B is also shown, which would not reduce the obstacle caused by the third road feature but would avoid the limit of the wheel's travel event. In some embodiments, the vehicle of FIG. 4 may implement mixed vehicle-body separation and road-following control, as demonstrated by the mixed control line 114C. In some embodiments, the vehicle control system may separately determine (e.g., using corresponding control modules) the outputs (e.g., force commands) for the separation control strategy of FIG. 2 and the tracking control strategy of FIG. 3 . The vehicle control system may then apply a blend ratio to determine the contribution of each control strategy to the overall output (e.g., force command) used to control the vehicle's active suspension. The blend ratio may be varied based on the output of the separation control module, such that a larger output from the separation control module results in a larger contribution from the tracking control module in the blended output. In this manner, the effect of road features such as the fifth road feature 302E may be mitigated with some separation control and not result in a limiting driving event. Exemplary embodiments of such vehicle control systems and associated methods are further discussed with reference to FIGS. 5-7.

[0054]

[0060] FIG. 5 is a block diagram of an exemplary embodiment of a vehicle control system 200. In the embodiment of FIG. 5, the vehicle control system 200 may be configured to control the vehicle's active suspension system and modify and / or control one or more motion parameters of the vehicle body. As shown in FIG. 5, the vehicle control system includes a separation control module 208 and a tracking control module 210. The separation control module may be configured to implement rigid skyhook control (e.g., see FIG. 2) or other skyhook control that increases the amount of vehicle-body separation compared to other control strategies implemented by the vehicle control system. In some embodiments, the separation control module 208 may have, for example, symmetrical suspension compression and rebound gains appropriate for vehicle-body separation. In the embodiment of FIG. 5, inertial vehicle body velocity 202 (e.g., vehicle body parameters) is an input to the separation control module 208, and in some embodiments, the only input. Inertial velocity may, in some embodiments, be measured by one or more accelerometers arranged on the vehicle body. In other embodiments, other vehicle body information, such as vehicle body parameters, may be input to the separation control module, as the disclosure is not so limited. The tracking control module 210 may implement a mixed skyhook and ground hook control in some embodiments (e.g., a weak skyhook or a weak ground hook) such that the amount of vehicle body separation may be reduced compared to the skyhook control implemented by the separation control module. In some embodiments, the tracking control module 210 may have asymmetric gains for compression and rebound of the suspension system. For example, in some embodiments, the tracking control module 210 may provide greater damping for rebound compared to compression. In the embodiment of FIG. 5, the tracking control module 210 has as inputs suspension velocity 204 (e.g., a suspension parameter) and inertial velocity 202 (e.g., a vehicle body parameter). In some embodiments, the suspension velocity may be provided by one or more sensors of the active suspension system and / or as feedback from active suspension system actuators. In other embodiments, any suitable combination of vehicle body information and suspension information may be utilized as inputs to the tracking control module.Both the separation control module 208 and the tracking control module 210 may generate outputs based on their respective inputs. Each of these outputs may be a total force command for controlling the motion of the vehicle body. These outputs may be determined independently of each other based on the control objectives of different controllers. As discussed below, these independent outputs may ultimately be used to determine the output of the mixed force 218. It should be noted that the process described below with reference to exemplary FIG. 5 may, in some embodiments, occur iteratively and in real time.

[0055]

[0061] The output of the separation control module 208 may be utilized by the vehicle control system 200 to determine a blend ratio at block 212. In some embodiments, the blend ratio may be a value between 0 and 1, where the value represents the relative contribution of the tracking control module 210 to the total blended power. As shown in block 216, the total blended power 218 may be determined according to the formula F1*(1-k)+F2*k, where k is the blend ratio, F1 is the output of the separation control module 208, and F2 is the output of the tracking control module 210. For example, a blend ratio of 0 may represent full control by the separation control module 208 (e.g., 100% of the blended power output is contributed by the output of the tracking control module). Alternatively, a blend ratio of 1 may represent full control by the tracking control module 210 (e.g., 100% of the blended power output is contributed by the output of the tracking control module). In some embodiments, the blend ratio may be expressed as a leading term and a trailing term. In such embodiments, the former term may be between 0 and 1, and the latter term may be between 0 and 1, provided that the sum of the former and latter terms equals 1. The former term of the blending ratio may be proportional to the contribution of the isolation control module 208 (or another controller in other embodiments). The latter term may be proportional to the contribution of the tracking control module 210 (or another controller in other embodiments). For example, the blending ratio may be expressed as a former term of 0.25 and a latter term of 0.75. In such an example, the isolation control module 208 may contribute 25% of the total blended output, and the tracking control module 210 may contribute 75% of the total blended output. The blending ratios may be expressed as any suitable values ​​or relationships that may be added to determine the total combined output, as the disclosure is not so limited.

[0056]

[0062] According to some embodiments, as shown in FIG. 5 , the blend ratio may be determined by the vehicle control system based solely on the output from the separation control module 208. The inventors recognize that the separation control module output may be highly interactive with suspension travel and may provide a cleaner signal that is less sensitive to noise compared to determining the blend ratio with direct sensor input. In particular, in the exemplary embodiment of FIG. 5 , the blend ratio is not determined based on the tracking control module output. Thus, the blend ratio is a function of the separation control module output and may be determined automatically based on the instantaneous output of the separation control module, although it is also contemplated that the blend ratio may be determined based on the output of the separation control module over a period of time. In some embodiments, the blend ratio may be proportional to the separation control module output. For example, the blend ratio may be proportional to the force command output by the separation control module. In some embodiments, if the determined separation force command output exceeds 80% of maximum actuator capacity, a proportional action may move the blend ratio toward the tracking force command output. In some such embodiments, when the separation force command output is less than 80% of the maximum actuator displacement, the mixture ratio may be constant or otherwise non-proportional to the separation force command output, which may favor the separation force command output. The proportionality between the mixture ratio and the separation control module output may allow the mixture ratio to be sensitive to large increases in the separation control module output, which may otherwise result in a limiting driving event. In some embodiments, the mixture ratio may be related to the integral of the separation control module output, which may help modify the mixture ratio when a prolonged force is applied (e.g., greater than a threshold length or time). In some embodiments, other tuning parameters may be utilized to determine the mixture ratio based on the output from the separation control module. For example, in some embodiments, a notch filter may be utilized to remove energy from the force command at selected frequencies, reducing trigger sensitivity. As an example, a filter placed between 1 and 3 Hz may generate a bias toward the separation mode where the vehicle exhibits natural frequency resonance.As another example, a dead zone parameter may be utilized to allow an integrator to ignore a portion of the force output to avoid increasing the mix ratio for lower force outputs at forces below 50% of the actuator capacity. In other embodiments, any suitable parameter may be utilized to transmit the isolation control module output to the mix ratio, as the disclosure is not so limited. In some embodiments, optional information, including user input and predictive information, may be utilized to determine the mix ratio. In some embodiments, an external trigger 206 may cause the vehicle control system to modify one or more parameters of the mix ratio determination of block 212.

[0057]

[0063] In some embodiments, such as that shown in FIG. 5, optional predictive road information 220 may contribute to the blend ratio determination in block 212 based on the output of the separation control module 208. The predictive road information may be obtained from one or more predictive sensors (e.g., LIDAR, camera, etc.) or received from one or more on-board or remote databases N. In some embodiments, the predictive road information may be used to adjust one or more parameters of the blend ratio determination (e.g., coefficients for the proportional and integral components of the determination). In some embodiments, the predictive road information may be used to establish a lower or upper limit for the blend ratio. A lower limit may be a threshold blend ratio that the blend ratio should be above. An upper limit may be a threshold blend ratio that the blend ratio should be below. In some such embodiments, the predictive information may indicate small road features (e.g., bumps or potholes or other road features that are smaller than a threshold size, length, and / or duration during travel) that can be fully compensated for by the separation control module. In some embodiments, an upper limit may be applied to the blend ratio so that the output from the separation control module 208 can correspond to most of the resulting blended force command. In some other such embodiments, the predictive road information may indicate significant road features that cannot be fully accounted for by the separation control module (e.g., slopes or other road features greater than a threshold magnitude, length, and / or duration of travel). According to this example, a floor may be applied to the blend ratio to set a minimum contribution to the total output from the tracking control module that avoids limiting driving events. In still other embodiments, the predictive road information may be utilized as part of a calculation combined with the output from the separation control module.

[0058]

[0064] In some embodiments, such as that shown in FIG. 5 , user input 222 may optionally contribute to the mix ratio determination in block 212. For example, user input 222 may be received at a user interface from a vehicle user. The user input, in some embodiments, may indicate a setting or operating mode. Vehicle control system 200 may determine the mix ratio in block 212 based at least in part on the user input, for example, by updating one or more parameters in the mix ratio determination based on the output of isolation control module 208. In an example of user input 222 in comfort mode, the mix ratio determination may more favorably configure the isolation control module to maximize vehicle body isolation. For example, in some embodiments, the mix ratio may have one or more parameters modified to be less sensitive (e.g., the proportionality coefficient may be reduced) to increase the isolation control module output. As another example, in some embodiments, an upper limit on the mix ratio may be set to cap the tracking control module's contribution to the mixed force 218. In sport mode, the mix ratio determination may more favorably configure the tracking control module to introduce feedback from vehicle body drive motion. For example, in some embodiments, the blending ratio may have one or more parameters modified to be more sensitive (e.g., the proportionality coefficient may be increased) to increase the isolation control module output. As another example, in some embodiments, a lower limit for the blending ratio may be set such that the tracking control module's contribution to the blended force 218 has a predetermined minimum non-zero value. Other modes are also contemplated, as the present disclosure is not so limited in this regard.

[0059]

[0065] In some cases, the inventors recognize that the raw blend ratio determined in block 212 may change rapidly because it is a function of the instantaneous separation force command from the separation control module 208. To reduce repeated cycling between full tracking and full separation control, in some embodiments, a hit / hold module may be applied to the raw blend ratio determined in block 212 in block 214. The hit / hold module may enforce a predetermined blend ratio if a road event longer than a threshold time is detected. In some embodiments, the hit / hold module may maintain a blend ratio greater than a threshold blend ratio for a predetermined time (e.g., the hit / hold module may enforce a lower limit on the blend ratio for a predetermined time). For example, the hit / hold module may assign a value of 1 to the blend ratio if a road event longer than the threshold time is detected. In some embodiments, the threshold time may be 1 second. In some embodiments, the predetermined time may be approximately 1 second, although both times greater than and less than 1 second may be used as the disclosure is not so limited. 2 may be driven for a time less than the threshold time, while the road feature in FIG. 3 may be driven for a time greater than the threshold time. In some embodiments, the hit / hold module may assign a lower limit other than 1 to the blend ratio. In some embodiments, block 214 may further smooth the blend ratio fluctuations by applying a low-pass filter to obtain a filtered blend ratio. The low-pass filter may remove high-frequency components that may be undesirable for suspension control. Suitable cutoff frequencies for the low-pass filter may include 0.5-2 Hz. The smoothing in block 214 may be optional in some embodiments. After the smoothing in block 214, the filtered and / or smoothed blend ratio may be used to determine the contributions of the decoupling control module 208 and the tracking control module 210 in block 216. From this determination, a blended force 218 output may be obtained, which may be used to command various actuators in the active suspension system.

[0060]

[0066] The blended force 218 output of the process described with reference to FIG. 5 is the total force output to reflect the desired control of the vehicle body. The blended force output may be allocated to the individual actuators of the active suspension system by a vehicle control system isolation process. It should also be noted that while a particular formula for applying the blend ratio is described with reference to FIG. 5, other formulas may be utilized as the present disclosure is not so limited. For example, the isolation control module 208 and the tracking control module 210 may have different gains such that the magnitudes of their respective outputs are not equal. Thus, in some embodiments, the blend ratio values ​​and formulas for determining the blended force 218 may be varied to compensate for these different magnitudes.

[0061]

[0067] 6 is a flow diagram of an exemplary embodiment of a method for controlling a vehicle. In block 400, vehicle information is received from at least one sensor. The vehicle information may include suspension information (e.g., suspension parameters such as suspension speed) and vehicle body information (e.g., vehicle body parameters such as vehicle body speed). In block 402, a vehicle body separation force command is determined by the separation control module based on the vehicle body information. For example, the vehicle body separation force command may be determined based only on the vehicle body speed in some embodiments. In block 404, a road following force command is determined by the tracking control module based on the suspension information and the vehicle body information. For example, the road following force command may be determined based on the vehicle body speed and the suspension speed.

[0062]

[0068] In block 406, a blend ratio is determined by the blending module, for example, based on the vehicle body separation force command. In some embodiments, the blend ratio may be proportional to the vehicle body separation force command from block 402, as previously described above. In some embodiments, the blend ratio may vary between 0 and 1 and may represent a ratio or weighting factor. In block 408, a total force command is determined based at least in part on the blend ratio, the vehicle body separation force command, and the road following force command. For example, in some embodiments, the vehicle body separation force command and the road following force command may each be created from a percentage component of the total force command based on the blend ratio. For example, if the blend ratio was 0.25, the total force command would be the sum of 25% of the road following force command and 75% of the vehicle body separation force command. According to this example, the total force command may include a first portion and a second portion, where the first portion is based on the blend ratio and the vehicle body separation force command, and the second portion is based on the blend ratio and the road following force command. In some embodiments, the first portion may be proportional to the blending ratio and the vehicle body separation force command, and the second portion may be proportional to the blending ratio and the road-following force command. The total force command may be representative of a force sought by the vehicle control system to achieve a desired movement of the vehicle body (e.g., a blend of separation control and tracking control). In block 410, at least one actuator of the active suspension system may be commanded to apply an intervention force between at least one of the vehicle's multiple wheels and the vehicle body of the vehicle that is based at least in part on the total force command.

[0063]

[0069] Optionally, the method of Figure 6 may be repeated during active control of the vehicle. In some embodiments, the method of Figure 6 may be performed by a vehicle control system, particularly at least one processor of the vehicle control system. The method of Figure 6 may be stored as computer-readable instructions on a non-transitory computer-readable medium for execution by at least one processor. In some embodiments, the steps of Figure 6 may be re-instructed. For example, the road following force command may be determined before the separation force command. In some embodiments, some of the steps of Figure 6 may be performed simultaneously in parallel. For example, the road following force command may be determined simultaneously with the separation force command as part of a parallel process.

[0064]

[0070] FIG. 7 is a flow diagram of another embodiment of a method for controlling a vehicle. In block 500, a vehicle body speed of the vehicle is determined. Information from a sensor, such as an accelerometer, may be used to determine the vehicle body speed. In block 502, a suspension speed (e.g., a suspension parameter) of the vehicle is determined. For example, feedback from one or more suspension sensors (e.g., accelerometers) and / or suspension actuators may be used to determine the speed of the suspension or wheels along its range of motion. In block 504, a first output of a first control module is determined based on the vehicle body speed (e.g., the vehicle body parameter). For example, the first control module may be a separate control module that implements stiff skyhook control or other skyhook control based on the vehicle body speed as an input. In some embodiments, the first output may be a first force command. In block 506, a second output of a second command module is determined based on the vehicle body speed and the suspension speed. For example, the second control module may be a road-following control module that implements weak skyhook or weak groundhook control based on the vehicle body speed as an input, providing a reduced level of skyhook control compared to the separate control module. In some embodiments, the second output may be a second force command.

[0065]

[0071] In block 508, a blend ratio is determined based on the first output. In some embodiments, the blend ratio may be proportional to the first output from block 504. In some embodiments, the blend ratio may vary between 0 and 1 and may represent a ratio or weighting factor. In block 510, a force command is determined based at least in part on the blend ratio, the first output, and the road's second output. For example, in some embodiments, the first output and the second output may each be created from a percentage component of the force command based on the blend ratio. For example, if the blend ratio were 0.50, the force command would be the sum of 50% of the first output and 50% of the second output. Following this example, the force command may include a first portion and a second portion, where the first portion is based on the blend ratio and the first output and the second portion is based on the blend ratio and the second output. In some embodiments, the first portion may be proportional to the blend ratio and the first output, and the second portion may be proportional to the blend ratio and the second output. The force command may be representative of a force sought by the vehicle control system to achieve a desired movement of the vehicle body (e.g., a blend of the two controllers). In block 512, at least one actuator of the active suspension system may be commanded to apply an active force between at least one of the vehicle's multiple wheels and the vehicle's chassis or body based at least in part on the force command.

[0066]

[0072] Optionally, the method of FIG. 7 may be repeated during active control of the vehicle. In some embodiments, the method of FIG. 7 may be performed by a vehicle control system, particularly at least one processor of the vehicle control system. The method of FIG. 7 may be stored as computer-readable instructions on a non-transitory computer-readable medium for execution by at least one processor. In some embodiments, the steps of FIG. 7 may be re-instructed. For example, the second output may be determined before the first output. In some embodiments, some of the steps of FIG. 6 may be performed simultaneously in parallel. For example, the first output may be determined simultaneously with the second output as part of a parallel process.

[0067]

[0073] The above-described embodiments of the technology described herein can be implemented in any number of ways. For example, embodiments may be implemented using hardware, software, or a combination thereof. When implemented in software, the software code can be executed on any suitable processor or collection of processors, whether provided within a single computer or distributed across multiple computers. Such processors may be implemented as integrated circuits with one or more processors within integrated circuit components, including commercially available integrated circuit components known in the art under names such as CPU chips, GPU chips, microprocessors, microcontrollers, or coprocessors. Alternatively, the processor may be implemented in custom circuitry, such as semi-custom circuitry resulting from constructing an ASIC or programmable logic device. As a still further alternative, the processor may be part of a larger circuit or semiconductor device, either commercially available, semi-custom, or custom. As a particular example, some commercially available microprocessors have multiple cores, so that one or a subset of those cores may constitute a processor. However, a processor may be implemented using circuitry in any suitable format.

[0068]

[0074] It should further be appreciated that the computer may be embodied in any number of forms, such as a rack-mounted computer, a desktop computer, a laptop computer, or a tablet computer. Additionally, the computer may be embodied in devices that are not generally considered to be computers, but which have suitable processing capabilities, including personal digital assistants (PDAs), smartphones, or any suitable portable or fixed electronic device.

[0069]

[0075] A computer may also have one or more input and output devices. These devices may be used, among other things, to present a user interface. Examples of output devices that may be used to provide a user interface include a printer or display screen for visual display of output, and a speaker or other sound-generating device for audible display of output. Examples of input devices that may be used in a user interface include a keyboard and pointing devices such as a mouse, touchpad, and digital tablet. As another example, a computer may receive input information through voice recognition or other audible methods.

[0070]

[0076] Such computers may be interconnected by one or more networks of any suitable form, including as a local area network or a wide area network, such as an enterprise network or the Internet. Such networks may be based on any suitable technology and operate according to any suitable protocol, and may include wireless networks, wired networks, or fiber optic networks.

[0071]

[0077] The various methods or processes outlined herein may also be coded as software executable on one or more processors utilizing any of a variety of operating systems or platforms. Additionally, such software may be written using any number of suitable programming languages ​​and / or programmatic or handwritten tools, and may be compiled as executable machine language code or intermediate code that runs on a framework or virtual machine.

[0072]

[0078] In this regard, the embodiments described herein may be embodied as a computer-readable storage medium (or multiple computer-readable media) (e.g., computer memory, one or more floppy disks, compact disks (CDs), optical disks, digital video disks (DVDs), magnetic tape, flash memory, circuitry in a field programmable gate array or other semiconductor device, or other tangible computer storage medium) encoded with one or more programs that, when executed on one or more computers or other processors, perform methods that implement the various embodiments discussed above. As is evident from the foregoing examples, a computer-readable storage medium may retain information for a sufficient period of time to provide computer-executable instructions in a non-transitory form. Such one or more computer-readable storage media may be transportable such that one or more programs stored thereon can be loaded onto one or more different computers or other processors to implement various aspects of the present disclosure, as discussed above. As used herein, the term “computer-readable storage medium” encompasses only non-transitory computer-readable media that can be considered to be an article of manufacture (i.e., an article of manufacture) or a machine. Alternatively or additionally, the present disclosure may be embodied as a computer-readable medium other than a computer-readable storage medium, such as a propagated signal.

[0073]

[0079] The terms "program" or "software" are used herein in a general sense to refer to any type of computer code or set of computer-executable instructions that can be utilized to program a computer or other processor to implement various aspects of the present disclosure, as discussed above. Additionally, according to one aspect of this embodiment, it should be recognized that one or more computer programs that, when executed, perform the methods of the present disclosure need not reside on a single computer or processor, but may be distributed in a modular manner among a number of different computers or processors to implement various aspects of the present disclosure.

[0074]

[0080] Computer-executable instructions may be executed by one or more computers or other devices in many forms, such as program modules. Generally, program modules include routines, programs, objects, components, data instructions, etc. that perform particular tasks or implement particular abstract data types. In particular, the functionality of the program modules may be assembled or distributed as desired in various embodiments.

[0075]

[0081] Also, the data structure may be stored in a computer-readable medium in any suitable manner. For simplicity of illustration, the data structure may be shown to have fields that are related through locations in the data structure. Such relationships may similarly be achieved by assigning storage for the fields to locations in the computer-readable medium that convey the relationships between the fields. However, any suitable mechanism may be used to establish relationships between information in the fields of the data structure, including through the use of pointers, tags, or other mechanisms that establish relationships between data elements.

[0076]

[0082] Various aspects of the present disclosure may be used alone, in combination, or in various configurations not specifically discussed in the previously described embodiments, and therefore are not limited in their application to the details and arrangements of components described above or illustrated in the drawings. For example, aspects described in one embodiment may be combined in any manner with aspects described in other embodiments.

[0077]

[0083] The embodiments described herein may also be embodied as methods, examples of which are provided. The acts performed as part of the method may be ordered in any suitable manner. Thus, embodiments may be constructed in which acts are performed in a different order than illustrated, and may include performing some acts simultaneously although shown as sequential acts in the exemplary embodiments.

[0078]

[0084] Additionally, some actions are described as being taken by a "user." It should be recognized that a "user" need not be an individual, and that in some embodiments, actions attributed to a "user" may be performed by a set of individuals and / or by an individual in combination with a computer-assisted tool or other mechanism.

[0079]

[0085] While the present teachings have been described in conjunction with various embodiments and examples, it is not intended that the present teachings be limited to such embodiments or examples. On the contrary, the present teachings encompass various alternatives, modifications, and equivalents, as will be recognized by those skilled in the art. Accordingly, the foregoing description and drawings are by way of example only.

Claims

1. The vehicle body, Multiple wheels and an active suspension system operably coupled to the plurality of wheels and the vehicle body, the active suspension system including at least one actuator configured to apply an active force to at least one of the plurality of wheels in at least one mode of operation; at least one processor configured to control the active suspension system, the at least one processor comprising: determining a first force command based on the vehicle body parameters; determining a second force command based on the vehicle body parameters and suspension parameters; determining a mix ratio based at least in part on the first force command; determining a third force command based at least in part on the mixture ratio, the first force command, and the second force command; at least one processor configured to command the at least one actuator to apply a force between at least one of the plurality of wheels and the vehicle body based at least in part on the third force command.

2. 2. The vehicle of claim 1, wherein said vehicle body parameter is vehicle body speed and said suspension parameter is suspension speed.

3. The system further includes at least one first sensor and at least one second sensor, wherein the at least one processor: receiving vehicle information from the at least one first sensor; determining the vehicle body parameters based on the vehicle information; receiving suspension information from the at least one second sensor; The vehicle of claim 1 or 2, further configured to determine the suspension parameters based on the suspension information.

4. 4. The vehicle of claim 3, wherein the at least one first sensor includes a first accelerometer arranged on the vehicle body and the at least one second sensor includes an accelerometer arranged on the active suspension system.

5. Determining the third force command comprises: determining a first portion of the third force command based on the mixture ratio and the first force command; The vehicle of any one of claims 1 to 4, further comprising determining a second portion of the third force command based on the mixture ratio and the second force command.

6. 6. The vehicle of claim 5, wherein the first portion of the third force command is proportional to the mixture ratio and the first force command, and the second portion of the third force command is proportional to the mixture ratio and the second force command.

7. The at least one processor determining whether a road event longer than a threshold time is occurring; The vehicle of claim 5 , further configured to maintain the mixture ratio greater than a threshold mixture ratio for a predetermined time upon determining that the road event is occurring for a period longer than the threshold time.

8. 6. The vehicle of claim 5, wherein the first portion of the third force command is proportional to a leading term of the mixture ratio and the second portion of the third force command is proportional to a trailing term of the mixture ratio.

9. 9. The vehicle according to claim 8, wherein the first term of the mixing ratio is between 0 and 1, the second term of the mixing ratio is between 0 and 1, and the sum of the first and second terms is 1.

10. The at least one processor 6. The vehicle of claim 5, further configured to apply a low pass filter to the mixture ratio to obtain a filtered mixture ratio, wherein the first portion of the third force command is determined based on the filtered mixture ratio, and the second portion of the third force command is determined based on the filtered mixture ratio.

11. 11. The vehicle of claim 1, wherein the first force command is configured to isolate the vehicle body from motion and the second force command is configured to move the vehicle body with a road surface.

12. A vehicle according to any preceding claim, wherein the third force command is configured to control heave and / or pitch of the vehicle.

13. 13. The vehicle of claim 1, further comprising a user interface, the user interface configured to receive input from a user, and the at least one processor further configured to determine the mixing ratio based at least in part on the input from the user.

14. 14. The vehicle of claim 1, further comprising a predictive sensor configured to acquire predictive road information, and wherein the at least one processor is further configured to determine the mixing ratio based at least in part on the predictive road information.

15. 15. The vehicle of any one of claims 1 to 14, wherein the first force command is a first output from a first control module and the second force command is a second output from a second control module.

16. The vehicle of any one of claims 1 to 15, wherein the at least one processor is further configured to determine the mixture ratio to avoid exceeding wheel travel thresholds for the plurality of vehicles.

17. 1. A method of controlling a vehicle, comprising: determining a first force command based on the vehicle body parameters; determining a second force command based on the vehicle body parameters and suspension parameters; determining a mix ratio based on the first force command; determining a third force command based at least in part on the mixture ratio, the first force command, and the second force command; and commanding at least one actuator of an active suspension system to apply an active force between at least one of a plurality of wheels of the vehicle and a vehicle body of the vehicle based at least in part on the third force command.

18. The method of claim 17 , wherein the vehicle body parameter is vehicle body velocity and the suspension parameter is suspension velocity.

19. receiving vehicle information from at least one first sensor; determining the vehicle body parameters based on the vehicle information; receiving suspension information from at least one second sensor; 19. The method of claim 17 or 18, further comprising determining the suspension parameters based on the suspension information.

20. 20. The method of claim 19, wherein the at least one first sensor includes a first accelerometer arranged on the vehicle body and the at least one second sensor includes an accelerometer arranged on the active suspension system.

21. Determining the third force command comprises: determining a first portion of the third force command based on the mixture ratio and the first force command; The method of any one of claims 17 to 20, comprising determining a second portion of the third force command based on the mixture ratio and the second force command.

22. 22. The method of claim 21 , wherein the first portion of the third force command is proportional to the mixture ratio and the first force command, and the second portion of the third force command is proportional to the mixture ratio and the second force command.

23. determining whether a road event longer than a threshold time is occurring; 22. The method of claim 21, wherein upon determining that the road event is occurring for a period longer than the threshold time, the mixture ratio is maintained above a threshold mixture ratio for a predetermined period of time.

24. 22. The method of claim 21, wherein the first portion of the third force command is proportional to a leading term of the mixture ratio and the second portion of the third force command is proportional to a trailing term of the mixture ratio.

25. 25. The method of claim 24, wherein the leading term of the mixing ratio is between 0 and 1, the trailing term of the mixing ratio is between 0 and 1, and the leading term and trailing term sum to 1.

26. 22. The method of claim 21, further comprising applying a low pass filter to the mixture ratio to obtain a filtered mixture ratio, wherein the first portion of the third force command is determined based on the filtered mixture ratio, and the second portion of the third force command is determined based on the filtered mixture ratio.

27. 27. The method of any one of claims 17 to 26, wherein the first force command is configured to isolate the vehicle body from motion and the second force command is configured to move the vehicle body with a road surface.

28. A method according to any one of claims 17 to 27, wherein the third force command is configured to control heave and / or pitch of the vehicle.

29. The method of any one of claims 17 to 28, further comprising receiving input from a user at a user interface, and wherein determining a pre-mix ratio is based at least in part on said input from said user.

30. 30. The vehicle of any one of claims 17 to 29, further comprising obtaining predictive road information with a predictive sensor, and wherein determining the blend ratio is based at least in part on the predictive road information.

31. 31. The vehicle of any one of claims 17 to 30, wherein the first force command is a first output from a first control module and the second force command is a second output from a second control module.

32. The vehicle of any one of claims 17 to 31, further comprising determining the mixture ratio to avoid exceeding wheel travel thresholds for the plurality of vehicles.

33. At least one non-transitory computer readable medium comprising instructions thereon which, when executed by at least one processor, perform the method of any one of claims 17 to 32.

Images