PATENT DOCUMENT

Publication Number: US-11345209-B1
Application Number: US-202016850369-A
Country: US
Kind Code: B1

Title: Suspension systems

Abstract:
A suspension system for a vehicle that has a vehicle body, a first wheel assembly that includes a first wheel hub, and a second wheel assembly that includes a second wheel hub. The suspension system includes a crossbar that is pivotally connected to the first wheel hub of the first wheel assembly and is pivotally connected to the second wheel hub of the second wheel assembly. The suspension system also includes a first active suspension actuator that is located near the first wheel assembly, is connected to the vehicle body, is connected to the crossbar, and supports the vehicle body with respect to the crossbar. The suspension system also includes a second active suspension actuator that is located near the second wheel assembly, is connected to the vehicle body, is connected to the crossbar, and supports the vehicle body with respect to the crossbar.

Claims:
What is claimed is: 
     
       1. A suspension system for a vehicle that has a vehicle body, a first wheel assembly that includes a first wheel hub, and a second wheel assembly that includes a second wheel hub, the suspension system comprising:
 a crossbar that is connected to the first wheel assembly and is connected to the second wheel assembly; 
 a first active suspension actuator that is located near the first wheel assembly, is connected between the vehicle body and the crossbar, and is operable to apply force to the crossbar to dampen acceleration of the vehicle body; 
 a first passive suspension component that is connected between the vehicle body and the crossbar in parallel with the first active suspension actuator to support a static load of the vehicle body with respect to the crossbar; 
 a second active suspension actuator that is located near the second wheel assembly, is connected between the vehicle body and the crossbar, and is operable to apply force to the crossbar to dampen acceleration of the vehicle body; and 
 a second passive suspension component that is connected between the vehicle body and the crossbar in parallel with the second active suspension actuator to support the static load of the vehicle body with respect to the crossbar. 
 
     
     
       2. The suspension system of  claim 1 , wherein the crossbar is pivotally connected to the first wheel hub by a first ball joint and the crossbar is pivotally connected to the second wheel hub by a second ball joint. 
     
     
       3. The suspension system of  claim 1 , wherein the crossbar is connected to at least one of the first wheel assembly or the second wheel assembly by a lateral decoupling linkage to allow relative lateral motion of the first wheel assembly and the second wheel assembly. 
     
     
       4. The suspension system of  claim 1 , wherein the first active suspension actuator and the second active suspension actuator are each mounted in a substantially vertical orientation. 
     
     
       5. The suspension system of  claim 1 , wherein the first active suspension actuator and the second active suspension actuator are linear actuators. 
     
     
       6. The suspension system of  claim 1 , further comprising:
 a first wheel hop damper that is connected to the crossbar between the first wheel assembly and the first active suspension actuator and is controllable to counteract wheel hop of the first wheel assembly; and 
 a second wheel hop damper that is connected to the crossbar between the second wheel assembly and the second active suspension actuator and is controllable to counteract wheel hop of the second wheel assembly. 
 
     
     
       7. The suspension system of  claim 1 , further comprising:
 a first wheel hop damper that is connected to the first active suspension actuator and is controllable to counteract wheel hop of the first wheel assembly; and 
 a second wheel hop damper that is connected to the second active suspension actuator and is controllable to counteract wheel hop of the second wheel assembly. 
 
     
     
       8. The suspension system of  claim 1 , wherein the first active suspension actuator is a first ball screw actuator, the first passive suspension component is a first coil spring, the second active suspension actuator is a second ball screw actuator, and the second passive suspension component is a second coil spring. 
     
     
       9. The suspension system of  claim 1 , wherein the first active suspension actuator is a first ball screw actuator, the first passive suspension component is a first air spring, the second active suspension actuator is a second ball screw actuator, and the second passive suspension component is a second air spring. 
     
     
       10. A suspension system for a vehicle that has a vehicle body, a first wheel assembly and a second wheel assembly, the suspension system comprising:
 a crossbar that is connected to the first wheel assembly and is connected to the second wheel assembly; 
 a first active suspension actuator that is located adjacent to the first wheel assembly, is connected between the vehicle body and the crossbar, and is operable to apply force to the crossbar; 
 a second active suspension actuator that is located near the second wheel assembly, is connected between the vehicle body and the crossbar, and is operable to apply force to the crossbar; and 
 an active suspension controller that controls operation of the first active suspension actuator and the second active suspension actuator to apply force to the crossbar in opposition to relative accelerations of the vehicle body and the first and second wheel assemblies in order to dampen vibration of the vehicle body. 
 
     
     
       11. The suspension system of  claim 10 , wherein the crossbar is a rigid structure. 
     
     
       12. The suspension system of  claim 10 , wherein the crossbar extends between the first wheel assembly and the second wheel assembly in a lateral direction relative to the vehicle body. 
     
     
       13. The suspension system of  claim 10 , wherein the crossbar is pivotally connected to the first wheel assembly by a first ball joint and the crossbar is pivotally connected to the second wheel assembly by a second ball joint. 
     
     
       14. The suspension system of  claim 10 , wherein the crossbar is connected to at least one of the first wheel assembly or the second wheel assembly by a lateral decoupling linkage to allow relative lateral motion of the first wheel assembly and the second wheel assembly. 
     
     
       15. The suspension system of  claim 10 , wherein the first active suspension actuator and the second active suspension actuator are each mounted in a substantially vertical orientation. 
     
     
       16. The suspension system of  claim 10 , wherein the crossbar extends between a first end located at the first wheel assembly and second end located at the second wheel assembly, the first active suspension actuator is positioned relative to the first wheel assembly so that application of substantially vertical forces to the first wheel assembly by the first active suspension actuator pivots the crossbar around a first effective pivot point located at the second end of the crossbar, and the second active suspension actuator is positioned relative to the second wheel assembly so that application of substantially vertical forces to the second wheel assembly by the second active suspension actuator pivots the crossbar around a second effective pivot point located at the first end of the crossbar. 
     
     
       17. The suspension system of  claim 10 , further comprising:
 a first passive suspension component that is connected between the vehicle body and the crossbar in parallel with the first active suspension actuator to support a static load of the vehicle body with respect to the crossbar; and 
 a second passive suspension component that is connected between the vehicle body and the crossbar in parallel with the second active suspension actuator to support the static load of the vehicle body with respect to the crossbar. 
 
     
     
       18. A suspension system for a vehicle that has a vehicle body, a first wheel assembly and a second wheel assembly, the suspension system comprising:
 a crossbar that is connected to the first wheel assembly and is connected to the second wheel assembly; 
 a first active suspension actuator that is located adjacent to the first wheel assembly in a first wheel well area that is defined by the vehicle body, is connected between the vehicle body and the crossbar, and is controlled to apply force to the crossbar to reduce vibrations that are experienced by the vehicle body; and 
 a second active suspension actuator that is located adjacent to the second wheel assembly in a second wheel well area that is defined by the vehicle body, is connected between the vehicle body and the crossbar, and is controlled to apply force to the crossbar to reduce vibrations that are experienced by the vehicle body. 
 
     
     
       19. The suspension system of  claim 18 , wherein the crossbar is pivotally connected to the first wheel assembly by a first ball joint and the crossbar is pivotally connected to the second wheel assembly by a second ball joint. 
     
     
       20. The suspension system of  claim 18 , wherein the crossbar is connected to at least one of the first wheel assembly or the second wheel assembly by a lateral decoupling linkage to allow relative lateral motion of the first wheel assembly and the second wheel assembly. 
     
     
       21. The suspension system of  claim 18 , wherein the first active suspension actuator and the second active suspension actuator are each mounted in a substantially vertical orientation. 
     
     
       22. The suspension system of  claim 18 , wherein the first active suspension actuator and the second active suspension actuator are linear actuators. 
     
     
       23. The suspension system of  claim 18 , further comprising:
 a first passive suspension component that is connected between the vehicle body and the crossbar in parallel with the first active suspension actuator to support a static load of the vehicle body with respect to the crossbar; and 
 a second passive suspension component that is connected between the vehicle body and the crossbar in parallel with the second active suspension actuator to support the static load of the vehicle body with respect to the crossbar. 
 
     
     
       24. The suspension system of  claim 23 , wherein the first active suspension actuator is a first ball screw actuator, the first passive suspension component is a first coil spring, the second active suspension actuator is a second ball screw actuator, and the second passive suspension component is a second coil spring. 
     
     
       25. The suspension system of  claim 23 , wherein the first active suspension actuator is a first ball screw actuator, the first passive suspension component is a first air spring, the second active suspension actuator is a second ball screw actuator, and the second passive suspension component is a second air spring.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims the benefit of U.S. Provisional Application No. 62/939,714, filed on Nov. 25, 2019, and this application also claims the benefit of U.S. Provisional Application No. 62/856,294, filed on Jun. 3, 2019, the contents of which are herein incorporated by reference herein in their entireties. 
    
    
     TECHNICAL FIELD 
     The application relates generally to suspension systems. 
     BACKGROUND 
     Vehicles typically include a suspension system. The suspension system supports a first part of the vehicle, which is referred to as the “sprung mass,” over a second part of the vehicle, which is referred to as the “unsprung mass.” The body and passenger compartment of a vehicle are typically included in the sprung mass. The tires, wheels, and components directly connected to the wheels are typically included in the unsprung mass. The suspension attempts to isolate the sprung mass from vibrations that are experienced by the unsprung mass. The vibrations that are experienced by the unsprung mass may have many causes, including the horizontal and vertical curvature of the roadway that the vehicle is travelling on, surface roughness of the roadway surface, imperfections in the roadway surface, and debris on the roadway surface. 
     The suspension system may include a number of different types of suspension components, such as dampers, springs, and bushings. Suspension components may be passive or active. Passive suspension components are mechanical devices that react to forces applied to them, typically by controlling the rate of movement away from a neutral position and the causing the system to return to the neutral position. Active suspension components are controlled systems that apply forces based on observed states, such as measured acceleration values for portions of the vehicle. For example, active suspension components may be actuated based in part on relative acceleration measurements that measure acceleration of the sprung mass relative to the unsprung mass. 
     SUMMARY 
     One aspect of the disclosure is a suspension system for a vehicle. The vehicle has a vehicle body, a first wheel assembly that includes a first wheel hub, and a second wheel assembly that includes a second wheel hub. The suspension system includes a crossbar that is pivotally connected to the first wheel hub of the first wheel assembly and is pivotally connected to the second wheel hub of the second wheel assembly. The suspension system also includes a first active suspension actuator that is located near the first wheel assembly, is connected to the vehicle body, is connected to the crossbar, and supports the vehicle body with respect to the crossbar. The suspension system also includes a second active suspension actuator that is located near the second wheel assembly, is connected to the vehicle body, is connected to the crossbar, and supports the vehicle body with respect to the crossbar. 
     In some implementations of the suspension system, the crossbar is pivotally connected to the first wheel hub by a first ball joint and the crossbar is pivotally connected to the second wheel hub by a second ball joint. 
     In some implementations of the suspension system, the crossbar is connected to at least one of the first wheel assembly or the second wheel assembly by a lateral decoupling linkage to allow relative lateral motion of the first wheel assembly and the second wheel assembly. 
     The first active suspension actuator and the second active suspension actuator may each be mounted in a substantially vertical orientation. The first active suspension actuator and the second active suspension actuator may be linear actuators. 
     In some implementations, the suspension system also includes a first wheel hop damper that is connected to the crossbar and is controllable to counteract wheel hop of the first wheel assembly and a second wheel hop damper that is connected to the crossbar and is controllable to counteract wheel hop of the second wheel assembly. In some implementations, the suspension system also includes a first wheel hop damper that is connected to the first active suspension actuator and is controllable to counteract wheel hop of the first wheel assembly and a second wheel hop damper that is connected to the second active suspension actuator and is controllable to counteract wheel hop of the second wheel assembly. 
     Another aspect of the disclosure is a suspension system for a vehicle that has a vehicle body, a first wheel assembly, and a second wheel assembly. The suspension system includes a crossbar that is connected to the first wheel assembly and the second wheel assembly. The crossbar includes a first crossbar portion that is connected to the first wheel assembly, the crossbar includes a second crossbar portion that is connected to the second wheel assembly, and the crossbar includes a connecting structure that connects the first crossbar portion to the second crossbar portion in a manner that allows relative lateral motion of the first crossbar portion and the second crossbar portion. The suspension system also includes a first active suspension actuator that is located near the first wheel assembly, is connected to the vehicle body, is connected to the crossbar, and supports the vehicle body with respect to the crossbar. The suspension system also includes a second active suspension actuator that is located near the second wheel assembly, is connected to the vehicle body, is connected to the crossbar, and supports the vehicle body with respect to the crossbar. 
     In some implementations of the suspension system, the connecting structure includes a telescopic joint that connects the first crossbar portion to the second crossbar portion. 
     In some implementations of the suspension system, the connecting structure includes a lateral decoupling linkage that connects the first crossbar portion to the second crossbar portion. 
     In some implementations of the suspension system, the first wheel assembly includes a first wheel hub, the second wheel assembly includes a second wheel hub, the crossbar is pivotally connected to the first wheel hub of the first wheel assembly, and the crossbar is pivotally connected to the second wheel hub of the second wheel assembly. The suspension system may also include a first ball joint that pivotally connects the crossbar to the first wheel hub and a second ball joint that pivotally connects the crossbar to the second wheel hub. 
     The first active suspension actuator and the second active suspension actuator may each be mounted in a substantially vertical orientation. The first active suspension actuator and the second active suspension actuator may be linear actuators. 
     Another aspect of the disclosure is a suspension system for a vehicle that has a vehicle body, a first wheel assembly, and a second wheel assembly. The suspension system includes a connecting bar that is connected to the first wheel assembly and the second wheel assembly. The suspension system also includes a first active suspension actuator that is located near the first wheel assembly, is connected to the vehicle body, is connected to the connecting bar, and supports the vehicle body with respect to the connecting bar. The suspension system also includes a second active suspension actuator that is located near the second wheel assembly, is connected to the vehicle body, is connected to the connecting bar, and supports the vehicle body with respect to the connecting bar. The suspension system also includes a lateral stabilizer that restrains lateral motion of the connecting bar. 
     In some implementations of the suspension system, the lateral stabilizer is connected to the connecting bar and to the vehicle body. The lateral stabilizer may include a Watt&#39;s linkage. The lateral stabilizer may include a Panhard rod. 
     In some implementations of the suspension system, the first wheel assembly includes a first wheel hub, the second wheel assembly includes a second wheel hub, the connecting bar is pivotally connected to the first wheel hub of the first wheel assembly, and the connecting bar is pivotally connected to the second wheel hub of the second wheel assembly. In some implementations, the suspension system also includes a first ball joint that pivotally connects the connecting bar to the first wheel hub, and a second ball joint that pivotally connects the connecting bar to the second wheel hub. 
     The first active suspension actuator and the second active suspension actuator may each be mounted in a substantially vertical orientation. The first active suspension actuator and the second active suspension actuator may be linear actuators. 
     Another aspect of the disclosure is a suspension system for a vehicle that has a vehicle body, a first wheel assembly that includes a first wheel hub, and a second wheel assembly that includes a second wheel hub. The suspension system includes a crossbar having a first lateral portion that is connected to the first wheel assembly, a second lateral portion that is connected to the second wheel assembly, a first longitudinal portion that is connected to the first lateral portion, a second longitudinal portion that is connected to the second lateral portion, and a central portion that extends between the first longitudinal portion and the second longitudinal portion such that central portion is longitudinally spaced from the first lateral portion and the second lateral portion by the first longitudinal portion and the second longitudinal portion. The suspension system also includes a first active suspension actuator that is located near the first wheel assembly, is connected to the vehicle body, is connected to the crossbar, and supports the vehicle body with respect to the crossbar, and a second active suspension actuator that is located near the second wheel assembly, is connected to the vehicle body, is connected to the crossbar, and supports the vehicle body with respect to the crossbar. 
     In some implementations, the central portion of the crossbar includes a joint that allows telescoping of the central portion of the crossbar. In some implementations, the central portion of the crossbar includes a joint that allows rotation of the first longitudinal portion of the crossbar and the second longitudinal portion of the crossbar. 
     Another aspect of the disclosure is a vehicle that includes a vehicle structure, a wheel assembly, a wheel hub that is connected to the wheel assembly, a suspension actuator that includes a housing, and a wheel mount that is connected to the housing of the suspension actuator to connect the wheel hub to the suspension actuator. The vehicle also includes a suspension arm that has a first end and a second end, is connected to the vehicle structure, and is connected to the suspension actuator. A first pivot joint connects the first end of the suspension arm to the housing of the suspension actuator. A second pivot joint that connects the second end of the suspension arm of the vehicle structure. The first pivot joint is configured to allow rotation around a first pivot axis that extends in a lateral direction with respect to the vehicle structure. The second pivot joint is configured to allow rotation around a second pivot axis that extends in the lateral direction with respect to the vehicle structure. 
     In some implementations of the vehicle, the first pivot axis is parallel to the second pivot axis. In some implementations of the vehicle, the first pivot joint includes an inner mounting structure, an outer mounting structure, and a first pivot pin that connects the housing of the suspension actuator to the first mounting structure and the second mounting structure such that the housing of the suspension actuator is located between the first mounting structure and the second mounting structure. 
     In some implementations of the vehicle, the wheel mount includes an upper mounting structure that is connected to the housing of the suspension actuator, a lower mounting structure that is connected to the housing of the suspension actuator, and a kingpin that is supported between the upper mounting structure and the lower mounting structure to allow rotation of the wheel hub and the wheel assembly to change a steering angle of the wheel assembly. 
     The vehicle may also include steering actuator that is connected to the wheel mount and is operable to rotate the kingpin to change the steering angle of the wheel assembly. 
     In some implementations of the vehicle, an upper end of the suspension actuator is connected to the vehicle structure. In some implementations of the vehicle, the suspension actuator includes an active suspension component. In some implementations of the vehicle, the suspension actuator includes a passive suspension component. 
     The vehicle may also include a steering linkage that is connected to the wheel hub. The vehicle may also include a propulsion linkage that is connected to the wheel hub. The vehicle may also include a steering actuator that is connected to the wheel mount and is operable to change a steering angle of the wheel assembly. 
     Another aspect of the disclosure is a vehicle that includes a vehicle structure, a crossbar that is connected to the vehicle structure, a wheel assembly, a wheel hub that is connected to the wheel assembly, a suspension actuator that includes a housing, and a wheel mount that is connected to the housing of the suspension actuator to connect the wheel hub to the suspension actuator. The vehicle also includes a suspension arm that has a first end and a second end, is connected to the crossbar, and is connected to the suspension actuator. A first pivot joint connects the first end of the suspension arm to the housing of the suspension actuator. A second pivot joint connects the second end of the suspension arm of the crossbar. The first pivot joint is configured to allow rotation around a first pivot axis that extends in a lateral direction with respect to the vehicle structure. The second pivot joint is configured to allow rotation around a second pivot axis that extends in the lateral direction with respect to the vehicle structure. 
     In some implementations of the vehicle, the crossbar is able to move with respect to the vehicle structure in one or more linear degrees of freedom. In some implementations of the vehicle, the crossbar is able to move with respect to the vehicle structure in one or more rotational degrees of freedom. In some implementations of the vehicle, the crossbar is connected to the vehicle structure by joints that constrain motion of the crossbar such that the crossbar is only able to move with respect to the vehicle structure in a generally longitudinal direction. 
     In some implementations of the vehicle, the first pivot axis is parallel to the second pivot axis. 
     In some implementations of the vehicle, the first pivot joint includes an inner mounting structure, an outer mounting structure, and a first pivot pin that connects the housing of the suspension actuator to the inner mounting structure and the outer mounting structure such that the housing of the suspension actuator is located between the inner mounting structure and the outer mounting structure. 
     In some implementations of the vehicle, the wheel mount includes an upper mounting structure that is connected to the housing of the suspension actuator, a lower mounting structure that is connected to the housing of the suspension actuator, and a kingpin that is supported between the upper mounting structure and the lower mounting structure to allow rotation of the wheel hub and the wheel assembly to change a steering angle of the wheel assembly. 
     In some implementations of the vehicle, the suspension actuator includes an active suspension component. In some implementations of the vehicle, the suspension actuator includes a passive suspension component. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a side view illustration that shows a vehicle that includes a suspension system. 
         FIG. 2  is a cross-section illustration taken according to line A-A of  FIG. 1  showing the suspension system. 
         FIG. 3  is a cross-section illustration taken according to line A-A of  FIG. 1  showing an alternative implementation of the suspension system in which wheel hop dampers are located on a crossbar. 
         FIG. 4  is a cross-section illustration taken according to line A-A of  FIG. 1  showing an alternative implementation of the suspension system in which wheel hop dampers are located on active suspension actuators. 
         FIG. 5  is a cross-section illustration taken according to line A-A of  FIG. 1  showing an alternative implementation of the suspension system in which a crossbar is connected to a wheel assembly by a lateral decoupling linkage. 
         FIG. 6  is a cross-section illustration taken according to line A-A of  FIG. 1  showing an alternative implementation of the suspension system in which a first crossbar portion is connected to a second crossbar portion by a lateral decoupling linkage. 
         FIG. 7  is a cross-section illustration taken according to line A-A of  FIG. 1  showing an alternative implementation of the suspension system in which a first crossbar portion is connected to a second crossbar portion by a telescopic joint. 
         FIG. 8  is a cross-section illustration taken according to line A-A of  FIG. 1  showing an alternative implementation of the suspension system in which lateral motion of a crossbar is restrained by a Watt&#39;s linkage. 
         FIG. 9  is a cross-section illustration taken according to line A-A of  FIG. 1  showing an alternative implementation of the suspension system in which lateral motion of a crossbar is restrained by a Panhard rod. 
         FIG. 10  is a perspective view illustration of a first alternative implementation of a suspension system that can be incorporated in the vehicle of  FIG. 1 . 
         FIG. 11  is a perspective view illustration of a second alternative implementation of a suspension system that can be incorporated in the vehicle of  FIG. 1 . 
         FIG. 12  is a perspective view illustration of a third alternative implementation of a suspension system that can be incorporated in the vehicle of  FIG. 1 . 
         FIG. 13  is a perspective view illustration of a fourth alternative implementation of a suspension system that can be incorporated in the vehicle of  FIG. 1 . 
         FIG. 14  is a perspective view illustration of a fifth alternative implementation of a suspension system that can be incorporated in the vehicle of  FIG. 1 . 
         FIG. 15  is a top view illustration that shows a suspension assembly that supports a wheel assembly with respect to a vehicle structure. 
         FIG. 16  is side view illustration that shows the suspension assembly of  FIG. 15 . 
         FIG. 17  is a front view illustration that shows the suspension assembly of  FIG. 15 . 
         FIG. 18  is a front view illustration that shows the suspension assembly of  FIG. 15  and includes a steering actuator. 
         FIG. 19  is a top view illustration that shows a suspension assembly that supports a wheel assembly with respect to a vehicle structure. 
         FIG. 20  is side view illustration that shows the suspension assembly of  FIG. 19 . 
         FIG. 21  is a front view illustration that shows the suspension assembly of  FIG. 19 . 
         FIG. 22  is top view illustration that shows a vehicle. 
         FIG. 23  is top view illustration that shows a vehicle. 
     
    
    
     DETAILED DESCRIPTION 
     The description herein relates to suspension systems that include a suspension component, referred to herein as a crossbar or a connecting bar, that extends laterally across the vehicle between opposed wheels (e.g., left and right wheels). The crossbar is connected to the wheels, for example, by connection to the hub of each wheel using a ball joint. At each side of the vehicle, adjacent to one of the opposed wheels, an active suspension actuator is connected to a body of the vehicle at a top end of the active suspension actuator, and is connected to the crossbar at a bottom end of the active suspension actuator. 
     The crossbar may be a beam or other generally rigid structure that spans the width of the car and transmits forces applied by the active actuator forces to the unsprung masses of the vehicle. By spanning the width of the vehicle between wheel assemblies, the crossbar allows application of active suspension forces to the wheel assemblies with very little moment applied to the wheel assemblies, and with a high motion ratio. By connecting the active suspension actuators to the crossbar instead of to the suspension linkages, the active suspension actuators can be mounted in a generally vertical orientation, which improves packaging. 
     The crossbar is included in the suspension system in addition to suspension linkages, and can be coupled with any traditional or active suspension-specific wheel kinematics configurations. The crossbar allows for improved load paths because it may be configured such that forces are transmitted between the tops of the active suspension actuators and the tires without coupling to other suspension member. The active suspension actuators that act upon the crossbar can be designed to carry dynamic loads only, but routing static loads through other suspension components (e.g., through passive suspension components). 
     The crossbars that are described herein are connected between two wheel assemblies and support the vehicle body using two active suspension actuators to improve the vertical load path from the road to the body. This arrangement may reduce or eliminate flanking load paths, such that most or all of the vertical loads are routed through the active suspension actuators, and coupling of vertical loads and lateral loads is reduced or eliminated. Thus, the active suspension actuators carry most or all of the static loads from the vehicle weight, and other components (e.g., bushings) can be designed without static load offset. 
     The crossbars described herein can be used in can be used in conjunction with kinematic arrangements that are intended to minimize coupling between longitudinal wheel motion and motion from other directions. This allows the longitudinal motion to be very soft with long travel and active control can be incorporated. By decoupling the vertical and longitudinal motions from other motions, dynamic effects such as bump steer and vibration can be minimized. 
       FIG. 1  is a side view illustration that shows a vehicle  100  that includes a suspension system  102 . The vehicle  100  also includes a vehicle body  104  and wheel assemblies, which include a front-left wheel assembly  106   a  and a rear-left wheel assembly  106   b  in the illustrated example. The suspension system  102  includes passive and active components that support the sprung mass of the vehicle  100  with respect to the unsprung mass of the vehicle  100 . The vehicle body  104  is part of the sprung mass of the vehicle, and is supported above the wheel assemblies, including the front-left wheel assembly  106   a  and the rear-left wheel assembly  106   b , by the suspension system  102 . The wheel assemblies, including the front-left wheel assembly  106   a  and the rear-left wheel assembly  106   b , are part of the unsprung mass of the vehicle  100  and are supported by an underlying surface, such as a roadway surface. The configuration shown in  FIG. 1  is generally applicable to the various examples of vehicles that will be shown and described herein. 
     The vehicle  100  may include a controller  108  and sensors  110  that are configured to control active components that are included in the suspension system  102 . The controller  108  may be a conventional computing device (e.g., having components such as a processor and a memory) that is provided with computer program instructions that allow the controller  108  to generate commands that regulate operation of the active components of the suspension system  102  using sensor signals that are generated by the sensors  110  and are provided to the controller  108  as inputs. The sensors  110  may include, as examples, one or more accelerometers that measure motion of the sprung mass of the vehicle  100 , one or more accelerometers that measure motion of the unsprung mass of the vehicle  100 , one or more cameras that monitor conditions around the vehicle  100 , and/or one or more three-dimensional sensors (e.g., LIDAR, structured light, etc.) that monitor conditions around the vehicle  100 . As an example, the computer program instructions of the controller  108  may monitor a relative acceleration of the sprung mass and the unsprung mass, determine a force to be applied by the active components of the suspension system  102  in opposition to the relative acceleration of the sprung mass and the unsprung mass, and output a command to the active components of the suspension system  102  that causes the active components to apply the force. 
     The vehicle  100  may be configured as a conventional road-going vehicle. As examples, the vehicle  100  may be configured as a passenger car, a utility vehicle, a sport utility vehicle, a truck, a bus, or a trailer. The vehicle  100  may include various actuator systems in addition to the suspension system  102 . As examples, the vehicle  100  may include a propulsion system, a braking system, and a steering system, which are not shown in  FIG. 1 . 
       FIG. 2  is a cross-section illustration taken according to line A-A of  FIG. 1  showing a suspension system  102  according to a first example. The suspension system  102  supports a sprung mass, including a vehicle body  104 , with respect to an unsprung mass of the vehicle, including wheel assemblies such as a left wheel assembly  206   a  and a right wheel assembly  206   b . In the illustrated example, the left wheel assembly  206   a  and the right wheel assembly  206   b  are front wheel assemblies, and a similar configuration can be utilized for rear wheel assemblies. The general configuration is the same as that described with respect to the vehicle  100  of  FIG. 1 . 
     The left wheel assembly  206   a  includes a left wheel  212   a , a left tire  214   a , and a left wheel hub  216   a . The left wheel  212   a , the left tire  214   a , and a left wheel hub  216   a  are all convention components. For example, the left wheel  212   a  may be a steel wheel of conventional design that supports the left tire  214   a , which may be a pneumatic tire. The left wheel hub  216   a  is fixed against rotation by components of the suspension system  102 . The left wheel  212   a  and the left tire  214   a  are supported by the left wheel hub  216   a  so that they may rotate. Propulsion, steering, and/or braking components may also be connected to and or integrated into the left wheel  212   a  and/or the left wheel hub  216   a.    
     The right wheel assembly  206   b  is located on a laterally opposite side of the vehicle relative to the left wheel assembly  206   a  and includes a right wheel  212   b , a right tire  214   b , and a right wheel hub  216   b , which are similar to the left wheel  212   a , the left tire  214   a , and a left wheel hub  216   a.    
     To support the vehicle body  104  with respect to the left wheel assembly  206   a , the suspension system  102  may include a left upper control arm  218   a , a left lower control arm  220   a , left passive suspension components  222   a , and a left active suspension actuator  224   a . The left upper control arm  218   a  and left lower control arm  220   a  connect the left wheel hub  216   a  to the vehicle body  104  such that the left wheel hub  216   a  is movable with respect to the vehicle body  104 , primarily in a generally vertical direction, for example, by pivoting joints (e.g., joints that allow rotation one or more rotational degrees of freedom). The left passive suspension components  222   a  may be connected in parallel with the left active suspension actuator  224   a  in order to support substantially all of (e.g., at least 95% in an unloaded condition) the static load applied to the unsprung mass (e.g., the left wheel assembly  206   a ) by the sprung mass (e.g., the vehicle body  104 ). As examples, the passive suspension components  222   a  may include springs, air springs (which may be low-frequency active components), shock absorbers, struts, dampers, bushings, and/or other types of passive components. The left active suspension actuator  224   a  will be described further herein. The left passive suspension component  222   a  could alternatively be located otherwise in order to support the static load of the vehicle body  104 . The arrangement of the left upper control arm  218   a  and the left lower control arm  220   a  is shown as an example and other arrangements can be used. 
     To support the vehicle body  104  with respect to the right wheel assembly  206   b , the suspension system  102  may include a right upper control arm  218   b , a right lower control arm  220   b , right passive suspension components  222   b  and a right active suspension actuator  224   b , which are similar to the left upper control arm  218   a , the left lower control arm  220   a , the left passive suspension components  222   a , and the left active suspension actuator  224   a  as previously described. 
     The suspension system  102  includes a crossbar  230 . The suspension system  102  also includes active suspension components that are configured to apply forces to the crossbar  230  as part of active suspension control. In the illustrated example, the active suspension components include the left active suspension actuator  224   a  and the right active suspension actuator  224   b.    
     The crossbar  230  is a structure that extends laterally across the vehicle between the left wheel assembly  206   a  and the right wheel assembly  206   b.    
     The crossbar  230  may be connected to the left wheel assembly  206   a  by connection to the left wheel hub  216   a  and the crossbar  230  may be connected to the right wheel assembly  206   b  by connected to the right wheel hub  216   b . The connections of the crossbar  230  to the left wheel assembly  206   a  and the right wheel assembly  206   b  may be pivotal connections. For example, a first end of the crossbar  230  may be pivotally connected the left wheel hub  216   a  and a second end of the crossbar  230  may be pivotally connected to the right wheel hub  216   b . By pivotally connecting the crossbar  230  to each of the left wheel hub  216   a  and the right wheel hub  216   b , forces that are applied to the crossbar  230  are applied to the left wheel assembly  206   a  and to the right wheel assembly  206   b.    
     Joints that allow pivotal movement in one or more rotational degrees of freedom may be used to connect the crossbar  230  to the left wheel hub  216   a  and to the right wheel hub  216   b . For example, the crossbar  230  may be connected to the left wheel hub  216   a  by a left ball joint  226   a  and the crossbar  230  may be connected to the right wheel hub  216   b  by a right ball joint  226   b.    
     The crossbar  230  is described as being connected to the left wheel hub  216   a  and the right wheel hub  216   b . It should be understood that these connections and other connections may be direct connections or may be indirect connections that include other structures such as joints. 
     The left active suspension actuator  224   a  and the right active suspension actuator  224   b  are each operable to apply forces to the crossbar  230 . Operation of the left active suspension actuator  224   a  and the right active suspension actuator  224   b  can be controlled to dampen accelerations of the vehicle body  104  relative to the wheel assemblies, including the left wheel assembly  206   a  and the right wheel assembly  206   b . The left active suspension actuator  224   a  and the right active suspension actuator  224   b  may be linear actuators. As one example, the left active suspension actuator  224   a  and the right active suspension actuator  224   b  may be hydraulic piston-cylinder actuators. As another example, the left active suspension actuator  224   a  and the right active suspension actuator  224   b  may be pneumatic piston-cylinder actuators. As another example, the left active suspension actuator  224   a  and the right active suspension actuator  224   b  may be pneumatic air springs. As another example, the left active suspension actuator  224   a  and the right active suspension actuator  224   b  may be electromagnetic linear actuators. As another example, the left active suspension actuator  224   a  and the right active suspension actuator  224   b  may be ball screw linear actuators that are driven by electric motors. Other types of actuators may be used as the left active suspension actuator  224   a  and the right active suspension actuator  224   b  to implement active suspension control. 
     The left active suspension actuator  224   a  and the right active suspension actuator  224   b  are each connected to the vehicle body  104  and to the crossbar  230 . These connections may be direct connections or may be indirect connections made using joints or other structures. The left active suspension actuator  224   a  and the right active suspension actuator  224   b  may each be connected to the vehicle body  104  and the crossbar  230  by rigid joints, by flexible joints, or by pivot joints that allow rotation in one or more rotational degrees of freedom. 
     In the illustrated example, the left active suspension actuator  224   a  is connected to the vehicle body  104  by the left upper joint  228   a  and to the crossbar  230  by the left lower joint  228   b . The right active suspension actuator  224   b  is connected to the vehicle body  104  by the right upper joint  229   a  and to the crossbar  230  by the right lower joint  229   b.    
     The left active suspension actuator  224   a  and the right active suspension actuator  224   b  may each be mounted in a substantially vertical orientation. As used herein, the term “substantially vertical orientation” includes orientations within ten degrees of a vertical orientation. By mounting each of the left active suspension actuator  224   a  and the right active suspension actuator  224   b  in a substantially vertical orientation, substantially vertical forces can be applied to the left wheel assembly  206   a  and the right wheel assembly  206   b , and the horizontal component of the applied force is small relative to vertical component of the applied force. 
     The left active suspension actuator  224   a  is located near the left wheel assembly  206   a  and the right active suspension actuator  224   b  is located near the right wheel assembly  206   b . For example, the left active suspension actuator  224   a  may be located in a left-side wheel well area defined by the vehicle body  104  and the right active suspension actuator  224   b  may be located in a right-side wheel well area defined by the vehicle body  104 . When the left active suspension actuator  224   a  is used to apply substantially vertical forces to the left wheel assembly  206   a , the effective pivot point of the crossbar  230  is located at the right end of the crossbar  230 , such as at the right ball joint  226   b . When the right active suspension actuator  224   b  is used to apply substantially vertical forces to the right wheel assembly  206   b , the effective pivot point of the crossbar  230  is located at the left end of the crossbar  230 , such as at the left ball joint  226   a.    
       FIG. 3  is a cross-section illustration taken according to line A-A of  FIG. 1  showing an alternative implementation of the suspension system  102  in which wheel hop dampers, including a left wheel hop damper  340   a , and a right wheel hop damper  340   b , are located on the crossbar  230 . The left wheel hop damper  340   a  is connected to the crossbar  230  and is controllable to counteract wheel hop of the left wheel assembly  206   a , and the right wheel hop damper  340   b  is connected to the crossbar  230  and is controllable to counteract wheel hop of the right wheel assembly  206   b . As an example, the wheel hop dampers  340   a ,  340   b  may include a tuned mass damper and/or a reaction mass actuator. Other active components may be used as the wheel hop dampers  340   a ,  340   b  to control wheel hop. 
     In the illustrated example, the left wheel hop damper  340   a  is positioned on the crossbar  230  between the left active suspension actuator  224   a  and the left wheel hub  216   a , and the right wheel hop damper  340   b  is positioned on the crossbar  230  between the right active suspension actuator  224   b  and the right wheel hub  216   b.    
     It should be that the wheel hop dampers  340   a ,  340   b  could be positioned elsewhere on the crossbar  230 . In addition, the wheel hop dampers  340   a ,  340   b  could be positioned on the left wheel assembly  206   a  and the right wheel assembly  206   b , for example, on the left wheel hub  216   a  and one the right wheel hub  216   b.    
       FIG. 4  is a cross-section illustration taken according to line A-A of  FIG. 1  showing an alternative implementation of the suspension system  102  in which wheel hop dampers, including a left wheel hop damper  440   a  and a right wheel hop damper  440   b , are located on the left active suspension actuator  224   a  and the right active suspension actuator  224   b . The left wheel hop damper  440   a  is connected to the left active suspension actuator  224   a  to counteract wheel hop of the left wheel assembly  206   a , and the right wheel hop damper  340   b  is connected to right active suspension actuator  224   b  to counteract wheel hop of the right wheel assembly  206   b . The wheel hop dampers  440   a ,  440   b  may be purely passive components, purely active components that are controllable (e.g., by the controller  108 ) in response to sensed conditions (e.g., acceleration values) to counteract wheel hop, or passive and active components in combination. As an example, the wheel hop dampers  440   a ,  440   b  may include a tuned mass damper and/or a reaction mass actuator. The tuned mass damper is an example of a passive wheel hop-dampening component and the reaction mass actuator is an example of an active wheel hop-dampening component. Other active components may be used as the wheel hop dampers  440   a ,  440   b  to control wheel hop. 
     It should be understood that the wheel hop dampers that are described with respect to  FIGS. 3-4  may be included in any of the implementations of the suspensions that are described herein. 
       FIG. 5  is a cross-section illustration taken according to line A-A of  FIG. 1  showing an alternative implementation of the suspension system in which a crossbar  530  is connected to the right wheel assembly  206   b  by a lateral decoupling linkage  532 . The crossbar  530  is similar to the crossbar  230  except as described herein. The lateral decoupling linkage  532  is pivotally connected to a right end of the crossbar  530  and is pivotally connected to the right wheel hub  216   b , for example, by the right ball joint  226   b . The ends of the lateral decoupling linkage  532  are offset vertically with respect to each other, which allows the lateral distance between the left wheel assembly  206   a  and the right wheel assembly  206   b  to vary slightly during operation of the vehicle  100 . A single lateral decoupling linkage is shown. It should be understood that the lateral decoupling linkage could instead be at the left end of the crossbar  230 , or that lateral decoupling linkages could be provided at both ends of the crossbar  230 . Thus, the crossbar  230  may be connected to at least one of the left wheel assembly  206   a  or the right wheel assembly  206   b  by a lateral decoupling linkage, such as the lateral decoupling linkage  532 , to allow relative lateral motion of the left wheel assembly  206   a  and the right wheel assembly  206   b.    
       FIG. 6  is a cross-section illustration taken according to line A-A of  FIG. 1  showing an alternative implementation of the suspension system  102  in which a left crossbar portion  630   a  is connected to a right crossbar portion  630   b  by a lateral decoupling linkage. The lateral decoupling linkage is a connecting structure that connects the left crossbar portion  630   a  to the right crossbar portion  630   b  in a manner that allows relative lateral motion of the left crossbar portion  630   a  and the right crossbar portion  630   b.    
     In the illustrated example, the lateral decoupling linkage is defined by a first link  632   a  having a first end pivotally connected to the left crossbar portion  630   a  and a second end pivotally connected to the right crossbar portion  630   b , and a second link  632   b  having a first end pivotally connected to the left crossbar portion  630   a  and a second end pivotally connected to the right crossbar portion  630   b . In combination with the left crossbar portion  630   a  and the right crossbar portion  630   b , the first link  632   a  and the second link  632   b  define a four-bar linkage arrangement that allows a small amount of relative lateral motion of the left crossbar portion  630   a  and the right crossbar portion  630   b.    
     Thus, the implementation of the suspension system  102  that is shown in  FIG. 6  includes a crossbar that includes a first crossbar portion that is connected to a first wheel assembly, a second crossbar portion that is connected to a second wheel assembly, and a connecting structure that connects the first crossbar portion to the second crossbar portion in a manner that allows relative lateral motion of the first crossbar portion and the second crossbar portion. In this example, the connecting structure is the lateral decoupling linkage that is defined by the first link  632   a  and the second link  632   b.    
       FIG. 7  is a cross-section illustration taken according to line A-A of  FIG. 1  showing an alternative implementation of the suspension system  102  in which a left crossbar portion  730   a  is connected to a right crossbar portion  730   b  by a telescopic joint  732 . The telescopic joint  732  is a connecting structure that connects the left crossbar portion  730   a  to the right crossbar portion  730   b  in a manner that allows relative lateral motion of the left crossbar portion  730   a  and the right crossbar portion  730   b.    
     The telescopic joint  732  connects the left crossbar portion  730   a  to the right crossbar portion  730   b  in a manner that allows the lateral distance between the left wheel assembly  206   a  and the right wheel assembly  206   b  to be varied based on insertion and retraction of the telescopic connection. In the illustrated example, the telescopic joint  732  is defined by an inner end portion of the left crossbar portion  730   a  that is received inside a cavity formed at an inner end portion of the right crossbar portion  730   b  such that it is slidable inside the cavity in the lateral direction. 
       FIG. 8  is a cross-section illustration taken according to line A-A of  FIG. 1  showing an alternative implementation of the suspension system  102  in which the suspension kinematics of the suspension system  102  are laterally flexible, and a crossbar  830  is restrained against lateral motion by a Watt&#39;s linkage  832 . The laterally flexible suspension kinematics of the suspension  102  may allow expansion and contraction of the lateral distance between the left wheel assembly  206   a  and the right wheel assembly  206   b . The Watt&#39;s linkage  832  is a lateral stabilizer that restrains lateral motion of the crossbar  830 . The Watt&#39;s linkage  832  is connected to the crossbar  830  and is also connected directly or indirectly to the vehicle body  104 . The Watt&#39;s linkage  832  is a conventional mechanical device that constrains the crossbar  830  to vertical motion to restrain lateral drift of the crossbar  830 . 
       FIG. 9  is a cross-section illustration taken according to line A-A of  FIG. 1  showing an alternative implementation of the suspension system in which the suspension kinematics of the suspension system  102  are laterally flexible, and a crossbar  930  is restrained against lateral motion by a Panhard rod  932 . The laterally flexible suspension kinematics of the suspension system  102  may allow expansion and contraction of the lateral distance between the left wheel assembly  206   a  and the right wheel assembly  206   b . The Panhard rod  932  is a lateral stabilizer that restrains lateral motion of the crossbar  930 . The Panhard rod is connected to the crossbar  930  (e.g., by a pivot joint on a first end of the Panhard rod  932 ) and is also connected directly or indirectly to the vehicle body  104  (e.g., by a pivot joint on a second end of the Panhard rod  932 . The Panhard rod  932  is a conventional mechanical device that constrains the crossbar  930  to vertical motion to restrain lateral drift of the crossbar  930 . 
       FIG. 10  is a perspective view illustration of an alternative implementation of a suspension system  1002  that can be incorporated in a vehicle, such as the vehicle  100  of  FIG. 1 . The suspension system  1002  includes a crossbar  1030  that is connected to a left wheel hub  1016   a  and a right wheel hub  1016   b  by a left ball joint  1026   a  and a right ball joint  1026   b . As will be explained herein, the left ball joint  1026   a , the right ball joint  1026   b , and part of the crossbar  1030  are aligned along a first axis  1050 . Another portion of the crossbar  1030  lies along a second axis  1052  that is longitudinally spaced (e.g., frontward or rearward) relative to the first axis  1050 . 
     The crossbar  1030  includes a left-side lateral portion  1054   a  and a right-side lateral portion  1054   b  that are connected to the left wheel hub  1016   a  and the right wheel hub  1016   b  by the left ball joint  1026   a  and the right ball joint  1026   b . The left-side lateral portion  1054   a  and the right-side lateral portion  1054   b  each extend along the first axis  1050  in the lateral direction. A left active suspension actuator  1024   a  and a right active suspension actuator  1024   b  are each connected to the crossbar  1030  at inner ends of the left-side lateral portion  1054   a  and the right-side lateral portion  1054   b . Upper ends of the left active suspension actuator  1024   a  and the right active suspension actuator  1024   b  are connected to a vehicle body  1004  by rigid, flexible, or pivotable joints. Lower ends of the left active suspension actuator  1024   a  and the right active suspension actuator  1024   b  are connected to the crossbar  1030  by rigid, flexible, or pivotable joints. Operation of the left active suspension actuator  1024   a  and the right active suspension actuator  1024   b  is otherwise as described with respect to the left active suspension actuator  224   a  and the right active suspension actuator  224   b.    
     The crossbar  1030  includes a left-side longitudinal portion  1056   a  and a right-side longitudinal portion  1056   b  that extend either longitudinally rearward (as in the illustrated example) or longitudinally forward relative to the left-side lateral portion  1054   a  and the right-side lateral portion  1054   b . At the opposite end of the left-side longitudinal portion  1056   a  and the right-side longitudinal portion  1056   b  from the front the left-side lateral portion  1054   a  and the right-side lateral portion  1054   b , a central portion  1058  extends between the left-side longitudinal portion  1056   a  and the right-side longitudinal portion  1056   b.    
     Longitudinal motion of the crossbar  1030  is controlled by a left damper  1060   a  and a right damper  1060   b  that are connected to the vehicle body  1004  and to the central portion  1058  of the crossbar  1030  by rigid, flexible, or pivotable joints. The left damper  1060   a  and the right damper  1060   b  may be mounted in a substantially longitudinal orientation so that they act in the longitudinal (front-to-back) direction. The left damper  1060   a  and the right damper  1060   b  may be passive components (e.g., springs or passive hydraulic dampers) or may be active components (e.g., hydraulic, pneumatic, or electric linear actuators). 
     The central portion  1058  of the crossbar  1030  may be mounted to the vehicle body  1004  in a manner that restrains vertical motion of the central portion of the crossbar  1030 . The central portion of the crossbar  1030  may include a joint structure that accommodates rotation and/or telescoping. As one example, the joint structure may allow rotation of the left-side lateral portion  1054   a  and the left-side longitudinal portion  1056   a  around the second axis  1052  relative to the right-side lateral portion  1054   b  and the right-side longitudinal portion  1056   b . As another example, the joint structure may allow relative lateral motion of the left-side lateral portion  1054   a  and the left-side longitudinal portion  1056   a  with respect to the right-side lateral portion  1054   b  and the right-side longitudinal portion  1056   b . Optionally, a lateral stabilizer  1059  (e.g., a Watt&#39;s linkage or a Panhard rod) may connected the central portion  1058  of the crossbar  1030  to the vehicle body  1004  to restrain lateral motion. Optionally, a link  1062  may be connected to the central portion  1058  of the crossbar  1030  and extend (e.g., upward or substantially vertically) to a connection with the vehicle body  1004  to constrain motion of the crossbar  1030  with respect to the vehicle body  1004 . 
     The crossbars described above with respect to  FIGS. 1-10  can be used in can be used in conjunction with kinematic arrangements that are intended to minimize coupling between longitudinal wheel motion and motion from other directions, as will be described with respect to  FIGS. 11-14 . 
       FIG. 11  is a perspective view illustration of an alternative implementation of a suspension system  1102  that can be incorporated in a vehicle, such as the vehicle  100  of  FIG. 1 , that has a vehicle body  1104 . The suspension system  1102  includes a crossbar  1130  that is connected to a left wheel hub  1116   a  and a right wheel hub  1116   b  by joints, such as ball joints, in the manner previously described in connection with the crossbars shown in  FIGS. 1-10 . 
     A left active suspension actuator  1124   a  and a right active suspension actuator  1124   b  are each connected to the crossbar  1130  near the left wheel hub  1116   a  and the right wheel hub  1116   b . Upper ends of the left active suspension actuator  1124   a  and the right active suspension actuator  1124   b  are connected to a vehicle body  1104  by rigid, flexible, or pivotable joints. Lower ends of the left active suspension actuator  1124   a  and the right active suspension actuator  1124   b  are connected to the crossbar  1130  by rigid, flexible, or pivotable joints. Operation of the left active suspension actuator  1124   a  and the right active suspension actuator  1124   b  is otherwise as described with respect to the left active suspension actuator  224   a  and the right active suspension actuator  224   b.    
     In addition to the crossbar  1130 , a first lateral link  1164  and a second lateral link  1166  connect the left wheel hub  1116   a  to the right wheel hub  1116   b . As with the crossbar  1130  joints, such as ball joints, may be used for the connections to the left wheel hub  1116   a  and the right wheel hub  1116   b . The crossbar  1130 , the first lateral link  1164  and the second lateral link  1166  may be anchored to the vehicle body  1104  to restrain lateral motion, for example, by a Watt&#39;s linkage or a Panhard rod. In combination, the crossbar  1130 , the first lateral link  1164  and the second lateral link  1166  constrain the left wheel hub  1116   a  and the right wheel hub  1116   b  to motion within respective planes that are perpendicular to the crossbar  1130 , the first lateral link  1164  and the second lateral link  1166 . The first lateral link  1164  and the second lateral link  1166  may be structures that have other functions in addition to constraining the distance between the left wheel hub  1116   a  and the right wheel hub  1116   b . For example, one of the first lateral link  1164  or the second lateral link  1166  may be a steering bar. 
     Longitudinal motion of the left wheel hub  1116   a  is regulated by a left lower longitudinal actuator  1168   a  and a left upper longitudinal link  1170   a . The left lower longitudinal actuator  1168   a  may be an actively controlled actuator that is connected to a lower part of the left wheel hub  1116   a  and is configured to extend and retract to regulate longitudinal movement of the left wheel hub  1116   a . The left upper longitudinal link  1170   a  is connected an upper part of the left wheel hub  1116   a  by a pivoting connection, for example, on a knuckle that extends upward from a body of the left wheel hub  1116   a , and is also connected to the vehicle body  1104  (e.g., by a fixed connection). The left upper longitudinal link  1170   a  may be a single degree of freedom link that allows longitudinal motion of the left wheel hub  1116   a  by pivoting with respect to a pivot point located above the central axis of the left wheel hub  1116   a.    
     Longitudinal motion of the right wheel hub  1116   b  is regulated by a right lower longitudinal actuator  1168   b  and a right upper longitudinal link  1170   b  which are identical to the left lower longitudinal actuator  1168   a  and left upper longitudinal link  1170   a , as previously described. 
       FIG. 12  is a perspective view illustration of an alternative implementation of a suspension system  1202  that can be incorporated in a vehicle, such as the vehicle  100  of  FIG. 1 , that has a vehicle body  1204 . The suspension system  1202  includes a crossbar  1230  that is connected to a left wheel hub  1216   a  and a right wheel hub  1216   b  by joints, such as ball joints, in the manner previously described in connection with the crossbars shown in  FIGS. 1-10 . 
     A left active suspension actuator  1224   a  and a right active suspension actuator  1224   b  are each connected to the crossbar  1230  near the left wheel hub  1216   a  and the right wheel hub  1216   b . Upper ends of the left active suspension actuator  1224   a  and the right active suspension actuator  1224   b  are connected to a vehicle body  1204  by rigid, flexible, or pivotable joints. Lower ends of the left active suspension actuator  1224   a  and the right active suspension actuator  1224   b  are connected to the crossbar  1230  by rigid, flexible, or pivotable joints. Operation of the left active suspension actuator  1224   a  and the right active suspension actuator  1224   b  is otherwise as described with respect to the left active suspension actuator  224   a  and the right active suspension actuator  224   b.    
     In addition to the crossbar  1230 , a lateral link  1264  also connects the left wheel hub  1216   a  to the right wheel hub  1216   b . As with the crossbar  1230 , joints, such as ball joints, may be used for the connections of the lateral link  1264  to the left wheel hub  1216   a  and the right wheel hub  1216   b . The crossbar  1230  and the lateral link  1264  may be anchored to the vehicle body  1204  to restrain lateral motion, for example, by a Watt&#39;s linkage or a Panhard rod. In combination, the crossbar  1230  and the lateral link  1264  constrain the motion of the left wheel hub  1216   a  and the right wheel hub  1216   b.    
     Longitudinal motion of the left wheel hub  1216   a  is regulated by a left lower longitudinal actuator  1268   a  and a left upper A-arm  1270   a . The left lower longitudinal actuator  1268   a  may be an actively controlled actuator that is connected to a lower part of the left wheel hub  1216   a  and is configured to extend and retract to regulate longitudinal movement of the left wheel hub  1216   a . The left upper A-arm  1270   a  is connected an upper part of the left wheel hub  1216   a  by a pivoting connection, for example, on a knuckle that extends upward from a body of the left wheel hub  1216   a , and is also connected to the vehicle body  1204  by a pivoting connection. Thus, the left upper A-arm  1270   a  may be a two degree of freedom link. 
     Longitudinal motion of the right wheel hub  1216   b  is regulated by a right lower longitudinal actuator  1268   b  and a right upper A-arm  1270   b  which are identical to the left lower longitudinal actuator  1268   a  and left upper A-arm  1270   a , as previously described. 
       FIG. 13  is a perspective view illustration of an alternative implementation of a suspension system  1302  that can be incorporated in a vehicle, such as the vehicle  100  of  FIG. 1 , that has a vehicle body  1304 . The suspension system  1302  includes a crossbar  1330  that is connected to a left wheel hub  1316   a  and a right wheel hub  1316   b  by joints, such as ball joints, in the manner previously described in connection with the crossbars shown in  FIGS. 1-10 . The crossbar  1330  may be anchored to the vehicle body  1304  to restrain lateral motion, for example, by a Watt&#39;s linkage or a Panhard rod. 
     A left active suspension actuator  1324   a  and a right active suspension actuator  1324   b  are each connected to the crossbar  1330  near the left wheel hub  1316   a  and the right wheel hub  1316   b . Upper ends of the left active suspension actuator  1324   a  and the right active suspension actuator  1324   b  are connected to a vehicle body  1304  by rigid, flexible, or pivotable joints. Lower ends of the left active suspension actuator  1324   a  and the right active suspension actuator  1324   b  are connected to the crossbar  1330  by rigid, flexible, or pivotable joints. Operation of the left active suspension actuator  1324   a  and the right active suspension actuator  1324   b  is otherwise as described with respect to the left active suspension actuator  224   a  and the right active suspension actuator  224   b.    
     Longitudinal motion of the left wheel hub  1316   a  is regulated by a left lower longitudinal actuator  1368   a  and a left upper A-arm  1370   a . The left lower longitudinal actuator  1368   a  may be an actively controlled actuator that is connected to a lower part of the left wheel hub  1316   a  and is configured to extend and retract to regulate longitudinal movement of the left wheel hub  1316   a . The left upper A-arm  1370   a  is connected an upper part of the left wheel hub  1316   a  by a pivoting connection, for example, on a knuckle that extends upward from a body of the left wheel hub  1316   a , and is also connected to the vehicle body  1304  by a pivoting connection. Thus, the left upper A-arm  1370   a  may be a two degree of freedom link. 
     Longitudinal motion of the right wheel hub  1316   b  is regulated by a right lower longitudinal actuator  1368   b  and a right upper A-arm  1370   b  which are identical to the left lower longitudinal actuator  1368   a  and left upper A-arm  1370   a , as previously described. 
     A left steering actuator  1372   a  is connected to the left wheel hub  1316   a , for example, at a knuckle at an upper part of the left wheel hub  1316   a . A right steering actuator  1372   b  is connected to the right wheel hub  1316   b , for example, at a knuckle at an upper part of the right wheel hub  1316   b.    
       FIG. 14  is a perspective view illustration of an alternative implementation of a suspension system  1402  that can be incorporated in a vehicle, such as the vehicle  100  of  FIG. 1 , that has a vehicle body  1404 . The suspension system  1402  includes a crossbar  1430  that is connected to a left wheel hub  1416   a  and a right wheel hub  1416   b  by joints, such as ball joints. The crossbar  1430  is implemented in accordance with the description of the crossbar  1030 , inclusive of the various portions, joints, and supporting structures described in connection with the crossbar  1030 . 
     A left active suspension actuator  1424   a  and a right active suspension actuator  1424   b  are each connected to the crossbar  1430  near the left wheel hub  1416   a  and the right wheel hub  1416   b . Upper ends of the left active suspension actuator  1424   a  and the right active suspension actuator  1424   b  are connected to a vehicle body  1404  by rigid, flexible, or pivotable joints. Lower ends of the left active suspension actuator  1424   a  and the right active suspension actuator  1424   b  are connected to the crossbar  1430  by rigid, flexible, or pivotable joints. Operation of the left active suspension actuator  1424   a  and the right active suspension actuator  1424   b  is otherwise as described with respect to the left active suspension actuator  224   a  and the right active suspension actuator  224   b.    
     Longitudinal motion of the left wheel hub  1416   a  is regulated by a left lower longitudinal actuator  1468   a  and a left upper A-arm  1470   a . The left lower longitudinal actuator  1468   a  may be an actively controlled actuator that is connected to a lower part of the left wheel hub  1416   a  and is configured to extend and retract to regulate longitudinal movement of the left wheel hub  1416   a . The left upper A-arm  1470   a  is connected an upper part of the left wheel hub  1416   a  by a pivoting connection, for example, on a knuckle that extends upward from a body of the left wheel hub  1416   a , and is also connected to the vehicle body  1404  by a pivoting connection. Thus, the left upper A-arm  1470   a  may be a two degree of freedom link. 
     Longitudinal motion of the right wheel hub  1416   b  is regulated by a right lower longitudinal actuator  1468   b  and a right upper A-arm  1470   b  which are identical to the left lower longitudinal actuator  1468   a  and left upper A-arm  1470   a , as previously described. 
     A left steering actuator  1472   a  is connected to the left wheel hub  1416   a , for example, at a knuckle at an upper part of the left wheel hub  1416   a . A right steering actuator  1472   b  is connected to the right wheel hub  1416   b , for example, at a knuckle at an upper part of the right wheel hub  1416   b.    
     In an alternative implementation the left upper A-arm  1470   a  and the right upper A-arm  1470   b  can be replaced with single degree of freedom links, as described with respect to the left upper longitudinal link  1170   a  and the right upper longitudinal link  1170   b.    
       FIG. 15  is a top view illustration that shows a suspension assembly  1500  that supports a wheel assembly  1502  with respect to a vehicle structure  1504 .  FIG. 16  is side view illustration that shows the suspension assembly  1500 .  FIG. 17  is a front view illustration that shows the suspension assembly  1500 . The suspension assembly  1500  is part of a vehicle, such as the vehicle  100  of  FIG. 1 . The description of the vehicle  100  is generally applicable to the suspension assembly  1500  and is incorporated in this description by reference. 
     The suspension assembly  1500  includes a laterally extending suspension arm that defines a leading-arm or trailing-arm type configuration. The wheel assembly  1502  may include a wheel and a tire (e.g., a pneumatic tire) that is mounted to the wheel). The wheel assembly  1502  is part of an unsprung mass of the vehicle and is supported by an underlying surface, such as a roadway surface. 
     The vehicle structure  1504  is a portion of the vehicle to which the suspension assembly  1500  is connected to support a sprung mass of the vehicle. As examples, the vehicle structure  1504  may be a frame, a subframe, a crossbar, a unibody, a monocoque, or other type of vehicle structure that may be supported by the suspension assembly to transfer load to the wheel assembly  1502 . 
     The suspension assembly  1500  includes a wheel hub  1506 , a suspension actuator  1508 , a wheel mount  1510 , and a suspension arm  1512 . A first pivot joint  1514  connects the suspension arm  1512  to the suspension actuator  1508 . A second pivot joint  1516  connects the suspension arm  1512  to the vehicle structure  1504 . 
     The wheel hub  1506  is connected to the wheel assembly  1502 . The wheel hub  1506  supports the wheel assembly so that the wheel assembly  1502  may rotate on a rotation axis during movement of the vehicle. As will be discussed further herein, the wheel hub  1506  is supported by components of the suspension assembly  1500  so that the wheel assembly  1502  may move upwards and downwards during movement of the vehicle to dampen vertical motion of the vehicle and to absorb vibrations. The wheel hub  1506  may also be supported for pivoting around a substantially vertical axis (e.g., within ten degrees of vertical) to allow steering. The wheel hub  1506  may use a conventional design, for example, including a non-rotating part and a rotating part that are connected to one another by a wheel bearing. 
     The suspension actuator  1508  is configured to control vertical motion of the wheel assembly. The suspension actuator  1508  extends from an upper end  1618  to a lower end  1619  in a substantially vertical direction (e.g., within ten degrees of vertical), which may include slight inclination relative to vertical in the lateral and/or longitudinal directions of the vehicle. The upper end  1618  of the suspension actuator  1508  is connected to the vehicle structure  1504  (e.g., by a ball joint or other joint). The lower end  1619  of the suspension actuator  1508  is connected to the wheel hub  1506  and to the suspension arm  1512  as will be explained herein. 
     The suspension actuator  1508  may include passive and/or active components. In the illustrated example, the suspension actuator  1508  includes an active suspension component  1620  and a passive suspension component  1621  that are arranged in series with respect to one another in a single actuator that performs both active and passive suspension functions. The suspension actuator  1508  also includes a housing  1522 , which in the illustrated example is located at the lower end  1619  of the suspension actuator  1508 , with the active suspension component  1620  being located in the housing  1522 . The housing  1522  is a structure that defines an enclosed interior, may be a rigid body, and serves as a structural component to which other structures can be attached. In the illustrated example, the housing  1522  is a cylindrical structure. In the illustrated example, the passive suspension component  1621  (depicted in the form of a spring) is located between the housing  1522  and the upper end  1618  of the suspension actuator  1508 . 
     The active suspension component  1620  is configured to apply force in opposition to high frequency vibrations in order to reduce the magnitude of the high frequency vibrations. The active suspension component  1620  is operable to apply forces between the vehicle structure  1504  and the wheel hub  1506 . Thus, operation of the active suspension component may cause expansion of the distance between the wheel hub  1506  and the vehicle structure  1504 , may resist expansion of the distance between the wheel hub  1506  and the vehicle structure  1504 , may cause contraction of the distance between the wheel hub  1506  and the vehicle structure  1504 , or may resist contraction of the distance between the wheel hub  1506  and the vehicle structure  1504 . 
     The active suspension component  1620  is controlled based one motion of the vehicle and/or motion of parts of the vehicle. As an example, the active suspension component  1620  may be controlled based on sensor signals that represent measured vibrations. The active suspension component  1620  can be controlled to dampen accelerations of the vehicle structure  1504  relative to the wheel assembly  1502 . 
     The active suspension component  1620  can be implemented any manner of controllable actuator, such as a controllable mechanical actuator, a controllable electromechanical actuator, a controllable pneumatic actuator and/or a controllable hydraulic actuator. As one example, the active suspension component  1620  may be a linear actuator. As another example, the active suspension component  1620  may be a hydraulic piston-cylinder actuator. As another example, active suspension component  1620  may be a pneumatic piston-cylinder actuator. As another example, active suspension component  1620  may be a pneumatic air spring. As another example, the active suspension component  1620  may be an electromagnetic linear actuator. As another example, the active suspension component  1620  may be a ball screw linear actuator that is driven by an electric motor. Other types of actuators may be used as the active suspension component  1620  to implement active suspension control. 
     The passive suspension component  1621  of the suspension actuator  1508  is configured to support the vehicle structure  1504 , to regulate motion of the vehicle structure  1504  relative to the wheel assembly  1502  and to dampen low-frequency vibrations and motions of the vehicle structure  1504  relative to the wheel assembly  1502 . As examples, the passive suspension component  1621  may include springs, air springs (which may be low-frequency active components), shock absorbers, struts, dampers, bushings, and/or other types of passive components. 
     The wheel mount  1510  is connected to the suspension actuator  1508 . The wheel mount  1510  is a structure that is configured to connect the suspension actuator  1508  to the wheel hub  1506 . The wheel mount  1510  may be rigidly connected to the suspension actuator  1508 , without intervening structures that allow relative motion of the wheel mount  1510  and a portion of the suspension actuator  1508  to which the wheel mount  1510  is connected. For example, the wheel mount  1510  may be connected to the suspension actuator without an intervening pivot joint or ball joint. In the illustrated example, the wheel mount  1510  includes structure that are directly connected to the housing  1522  of the suspension actuator  1508 , as will be explained. 
     The wheel mount  1510  may include an upper mounting structure  1624  that is connected to the housing  1522  of the suspension actuator  1508  and a lower mounting structure  1625  that is connected to the housing  1522  of the suspension actuator  1508 . As an example, the upper mounting structure  1624  and the lower mounting structure  1625  may be rigid structures that extend outward from the housing  1522  in order to define connection points at which the wheel hub  1506  can be connected to the suspension actuator  1508 . For example, the upper mounting structure  1624  and the lower mounting structure  1625  may extend outward from the housing  1522  of the suspension actuator  1508  in a substantially horizontal direction (e.g., within ten degrees of horizontal). For example, the upper mounting structure  1624  and the lower mounting structure  1625  may extend outward in a direction that is substantially perpendicular (e.g., within ten degrees of perpendicular) to an axis along which the suspension actuator  1508  extends between the upper end  1618  and the lower end  1619  of the suspension actuator  1508 . As another example, the upper mounting structure  1624  and the lower mounting structure  1625  may be plate-like, generally planar members that extend outward from the housing  1522  of the suspension actuator  1508 . 
     The wheel mount  1510  includes a structure that is connected to the wheel hub  1506 . In the illustrated example, the wheel mount  1510  includes a kingpin  1526  that extends between the upper mounting structure  1624  and the lower mounting structure. The wheel mount  1510  and the wheel hub  1506  define a steering pivot joint  1528  by which the wheel hub  1506  is pivotable with respect to the suspension actuator  1508  around a steering axis  1629  that is defined by the kingpin  1526 . For example, the kingpin  1526  may be supported between the upper mounting structure  1624  and the lower mounting structure  1625  to allow rotation of the wheel hub  1506  and the wheel assembly  1502  to change a steering angle of the wheel assembly  1502 . 
     In one implementation of the steering pivot joint  1528 , the kingpin  1526  is fixed to the upper mounting structure  1624  and the lower mounting structure  1625  of the wheel mount  1510 , and the wheel hub  1506  is connected to the kingpin  1526  such that the wheel hub  1506  is able to pivot around the kingpin  1526 . For example, the kingpin  1526  could extend through a corresponding aperture and/or bearing assembly that is included in the wheel hub  1506 . In another implementation of the steering pivot joint  1528 , the kingpin  1526  is fixed to the wheel hub  1506  and the kingpin  1526  extends between and is pivotally connected to the upper mounting structure  1624  and the lower mounting structure  1625 . The kingpin  1526  may be a single-piece structure or may be a multi-part structure. For example, in implementations in which the kingpin  1526  is fixed to the wheel hub  1506 , the kingpin  1526  may include a first portion that extends upward from part of the wheel hub  1506  to a pivoting connection with the upper mounting structure  1624  and a second portion that extends downward from a second part of the wheel hub  1506  to a pivoting connection with the lower mounting structure  1625 . 
     The wheel mount  1510  may be the only load-carrying member by which the wheel assembly  1502  is connected to the vehicle structure  1504 . Thus, the suspension assembly  1500  may lack other load-carrying connections to the wheel assembly  1502 , such as other suspension components (e.g., springs) and other control arms. Other non-load-carrying structures may, however, be connected to the wheel assembly  1502 . Examples of non-load-carrying structures include propulsion linkages and steering linkages. 
     In the illustrated example, the configuration of the wheel mount  1510  allows the wheel assembly  1502  to be a steered wheel with a controllable steering angle by pivoting the wheel assembly  1502  with respect to the wheel mount  1510 . The wheel mount  1510  could instead be configured define a fixed angular relationship for the wheel assembly  1502  if it is not a steered wheel. 
     The suspension arm  1512  is a rigid structure that is configured to constrain motion of the wheel assembly  1502 . The suspension arm  1512  extends in a substantially longitudinal direction (e.g., within ten degrees of a longitudinal direction) that corresponds to the nominal travel direction of the vehicle, such that it is configured as a leading arm or a trailing arm depending on its position relative to the wheel assembly  1502  and the vehicle structure  1504 . 
     The suspension arm  1512  has a first end  1530  and a second end  1531 . The first end  1530  of the suspension arm  1512  is connected to the suspension actuator  1508 . The second end  1531  of the suspension arm  1512  is connected to the vehicle structure  1504 . In the illustrated example, the first pivot joint  1514  is located at the first end  1530  of the suspension arm  1512  and connects the first end  1530  the suspension arm  1512  to the suspension actuator  1508 . The second pivot joint  1516  is located at the second end  1531  of the suspension arm  1512  and connects the second end  1531  of the suspension arm  1512  to the vehicle structure  1504 . 
     The first pivot joint  1514  extends along a first pivot axis  1515 . The first pivot axis  1515  may extend in a generally lateral direction (e.g., a cross-vehicle direction that is perpendicular to the nominal direction of travel of the vehicle) with respect to the vehicle structure  1504 . The second pivot joint  1516  extends along a second pivot axis  1517 . The second pivot axis  1517  may also extend in the generally lateral direction with respect to the vehicle structure  1504 . Accordingly, the first pivot axis  1515  may be parallel to the second pivot axis  1517 . 
     In the illustrated example, the first pivot joint  1514  of the suspension arm  1512  is defined by an outer mounting structure  1532  and an inner mounting structure  1533  that are located at the first end  1530  of the suspension arm  1512 . The outer mounting structure  1532  is located laterally outward from the suspension actuator  1508 . The inner mounting structure  1533  is located laterally inward from the suspension actuator  1508 . At least part of the housing  1522  of the suspension actuator  1508  is located between the outer mounting structure  1532  and the inner mounting structure  1533 . 
     The first pivot joint  1514  includes a first pivot pin  1534  that connects the suspension arm  1512  to the suspension actuator  1508 . The first pivot pin  1534  extends along the first pivot axis  1515 , is fixed to one of the suspension arm  1512  or the suspension actuator  1508 , and is pivotally connected to the other of the suspension arm  1512  and the suspension actuator  1508 . The first pivot pin  1534  may be a single piece structure that, for example, extends from the outer mounting structure  1532  to the inner mounting structure  1533  and extends through the housing  1522  of the suspension actuator  1508 . Alternatively, the first pivot pin  1534  may be a two-piece structure that, for example, includes a first part that extends from the outer mounting structure  1532  to a first connection with the housing  1522  of the suspension actuator  1508  and includes a second part that extends from the inner mounting structure  1533  to a second connection with the housing  1522  of the suspension actuator  1508 . 
     The suspension arm  1512  constrains motion of the wheel assembly  1502  along an arc, but given the length of the suspension arm  1512  relative to the range of motion of the wheel assembly  1502 , motion of the wheel assembly  1502  is effectively constrained by the suspension arm  1512  to be generally vertical over the range of motion of the wheel assembly  1502 . Thus, the suspension arm  1512  is configured to limit movement of the wheel assembly  1502  in directions other than the generally vertical direction. The suspension arm  1512  extends in the longitudinal direction, is inflexible in the longitudinal direction, and therefore limits movement of the wheel assembly  1502  in the longitudinal direction other than small deviations attributable to the arc-shaped generally vertical motion. The suspension arm  1512  may limit lateral motion of the wheel assembly  1502  because of the lateral orientation of the first pivot axis  1515  of the first pivot joint  1514  and because of the lateral orientation of the second pivot axis  1517  of the second pivot joint  1516 . 
     In the illustrated example, the second pivot joint  1516  of the suspension arm  1512  is defined by a mounting portion  1538 , a vehicle-side mounting structure  1540 , and a second pivot pin  1536 . The mounting portion  1538  and the vehicle-side mounting structure  1540  are connected to each other by the second pivot joint  1516 . The mounting portion  1538  is located at the second end  1531  of the suspension arm  1512 . The vehicle-side mounting structure  1540  is part of the vehicle structure  1504  or is connected to the vehicle structure  1504 . 
     The second pivot joint  1516  may be defined in part by apertures that are formed through the mounting portion  1538  and through the vehicle-side mounting structure  1540  to receive the second pivot pin  1536 . The second pivot pin  1536  may be fixed with respect to one of the mounting portion  1538  and the vehicle-side mounting structure  1540  and rotatable with respect to the other of the mounting portion  1538  and the vehicle-side mounting structure  1540 , or may be rotatable with respect to both the mounting portion  1538  and the vehicle-side mounting structure  1540 . 
     Each of the mounting portion  1538  and the vehicle-side mounting structure  1540  may include one or more parts that extend outward from the remainder of the suspension arm  1512  and the vehicle structure  1504 . Thus, for example, the second pivot joint  1516  may include multiple parts that are connected in an interleaved configuration. 
     A steering linkage  1507  may be connected to the wheel hub  1506  for steering control by a steering actuator (not shown) to change the steering angle of the wheel assembly  1502 . Alternatively, as shown in  FIG. 18 , a steering actuator  1807  may be connected to the wheel mount  1510  and to the kingpin  1526  to rotate the kingpin  1526  to thereby rotate the wheel hub  1506  to change the steering angle of the wheel assembly  1502 . The implementation shown in  FIG. 18  omits the steering linkage  1507  but otherwise includes all of the elements described in connection with the suspension assembly  1500 . 
       FIG. 19  is a top view illustration that shows a suspension assembly  1900  that supports a wheel assembly  1902  with respect to a vehicle structure  1904 .  FIG. 20  is side view illustration that shows the suspension assembly  1900 .  FIG. 21  is a front view illustration that shows the suspension assembly  1900 . The suspension assembly  1900  is part of a vehicle, such as the vehicle  100  of  FIG. 1 . The description of the vehicle  100  is generally applicable to the suspension assembly  1900  and is incorporated in this description by reference. The description of the suspension assembly  1500  is also generally applicable to the suspension assembly  1900  and is incorporated in this description by reference. Parts of the suspension assembly  1900  may be implemented in the manner described with respect to like-named parts of the suspension assembly  1500  except as otherwise described herein. 
     The suspension assembly  1900  includes a laterally extending suspension arm that defines a leading-arm or trailing-arm type configuration. The wheel assembly  1902  may include a wheel and a tire (e.g., a pneumatic tire) that is mounted to the wheel). The wheel assembly  1902  is part of an unsprung mass of the vehicle and is supported by an underlying surface, such as a roadway surface. 
     The vehicle structure  1904  is a portion of the vehicle to which the suspension assembly  1900  is connected to support a sprung mass of the vehicle. As examples, the vehicle structure  1904  may be a frame, a subframe, a crossbar, a unibody, a monocoque, or other type of vehicle structure that may be supported by the suspension assembly to transfer load to the wheel assembly  1902 . 
     The suspension assembly  1900  includes a wheel hub  1906 , a suspension actuator  1908 , a wheel mount  1910 , and a suspension arm  1912 . A first pivot joint  1914  extends along a first pivot axis  1915  and connects the suspension arm  1912  to the suspension actuator  1908 . A second pivot joint  1916  extends along a second pivot axis  1917  and connects the suspension arm  1912  to the vehicle structure  1904 . 
     In the suspension assembly  1500 , the suspension actuator  1508  is positioned laterally adjacent to the wheel hub  1506 , and a rotation axis of the wheel assembly  1502  extends through the suspension actuator  1508 . The wheel mount  1510  extends laterally outward from the suspension actuator  1508  to the wheel hub  1506 . This configuration is well-suited to use with non-driven wheels and with wheels that are driven by hub motors. 
     In the suspension assembly  1900 , a propulsion shaft  1942  may be connected to the wheel hub  1906  to cause rotation of the wheel assembly  1902  when driven by a motor (not shown). The suspension actuator  1908  is located longitudinally between the propulsion shaft  1942  and the vehicle structure  1904 . Thus, the suspension actuator  1908  is longitudinally offset from (e.g., forward or rearward from) the rotation axis of the wheel hub  1906  and the propulsion shaft  1942 . 
     The wheel mount  1910  extends longitudinally (e.g., forward or rearward) from the suspension actuator  1908  toward the propulsion shaft  1942  and extends laterally outward toward the wheel hub  1906  where the wheel mount  1910  is connected to the wheel hub  1906 . For example, the wheel mount  1910  may include an upper mounting structure  2024  and a lower mounting structure  2025 . The wheel mount  1910  may include a kingpin  1926  that extends between the upper mounting structure  2024  and the lower mounting structure  2025  to connect the wheel mount  1910  to the wheel hub  1906  (e.g., in a manner that allows rotation for steering). 
     The upper mounting structure  2024  is connected to the suspension actuator  1908  and to the wheel hub  1906 . The upper mounting structure  2024  extends from the suspension actuator  1908  to the wheel hub  1906  to transfer forces between the suspension actuator  1908  and the wheel hub  1906 . The upper mounting structure  2024  is located above the propulsion shaft  1942  in the area laterally adjacent to the wheel hub  1906 . 
     The lower mounting structure  2025  is connected to the suspension actuator  1908  and to the wheel hub  1906 . The lower mounting structure  2025  extends from the suspension actuator  1908  to the wheel hub  1906  to transfer forces between the suspension actuator  1908  and the wheel hub  1906 . The lower mounting structure  2025  is located below the propulsion shaft  1942  in the area laterally adjacent to the wheel hub  1906 . 
     The wheel assembly  1902  may be steered using a steering linkage  1907  or may be steered using a steering actuator that is connected to the wheel mount  1910  as described with respect to the steering actuator  1807  of  FIG. 18 . 
       FIG. 22  is top view illustration that shows a vehicle  2250 . The vehicle  2250  includes four suspension assemblies  2200 , four wheel assemblies  2202 , a vehicle structure  2204 , a vehicle body  2252  that is supported by the vehicle structure  2204 , a steering system  2254 . The suspension assemblies  2200  may be implemented in the manner described with respect to the suspension assembly  1500  and/or the suspension assembly  1900 . The descriptions of the suspension assembly  1500  and the suspension assembly  1900  are applicable to the vehicle  2250  and the suspension assemblies  2200 , and are incorporated in this description by reference. The suspension assemblies  2200  are connected to the vehicle structure  2204  as previously described with respect to the suspension assembly  1500  and the suspension assembly  1900 . 
       FIG. 23  is top view illustration that shows a vehicle  2350 . The vehicle  2350  includes four suspension assemblies  2300 , four wheel assemblies  2302 , a vehicle structure  2304 , a vehicle body  2352  that is supported by the vehicle structure  2304 , a steering system  2354 , and crossbars  2356  at front and rear longitudinal ends of the vehicle structure  2304 . The suspension assemblies  2300  may be implemented in the manner described with respect to the suspension assembly  1500  and/or the suspension assembly  1900 . The descriptions of the suspension assembly  1500  and the suspension assembly  1900  are applicable to the vehicle  2350  and the suspension assemblies  2300 , and are incorporated in this description by reference. 
     The suspension assemblies  2300  are not directly connected to the vehicle structure  2304  as previously described with respect to the suspension assembly  1500  and the suspension assembly  1900 . Instead, the suspension assemblies  2300  are connected to the crossbars  2356 , which are connected (e.g., directly) to the vehicle structure  2304 . The suspension assemblies  2300  are connected to crossbars  2356  by pivot joints in the manner described with respect to the second pivot joints  1516 ,  1916  that connect the suspension arms  1512 ,  1912  to the vehicle structures  1504 ,  1904  in the suspension assembly  1500  and the suspension assembly  1900 . 
     The crossbars  2356  are connected to the vehicle structure  2304  by joints  2358 . In one implementation, the joints  2358  rigidly connect the crossbars  2356  to the vehicle structure  2304 . In other implementations, the crossbars  2356  are able to move with respect to the vehicle structure  2304  over a limited range of motion in one or more linear and/or rotational degrees of freedom. In one implementation, the joints  2358  are compliant bushings. In another implementation, the joints  2358  are pivot joints. In another implementation, the joints  2358  are ball joints. In another implementation, the joints  2358  include sliding mounts and linear springs or dampers that regulate linear motion (e.g., in the longitudinal direction) of the crossbars  2356  with respect to the vehicle structure  2304 . The crossbars  2356  may be connected to the vehicle structure  2304  by the joints  2358  such that the joints  2358  constrain motion of the crossbars  2356  such that the crossbars  2356  are only able to move with respect to the vehicle structure in a generally longitudinal direction. 
     As described above, one aspect of the present technology is the gathering and use of data available from various sources to control operation of an active suspension system and thereby improve the ride quality of a vehicle. The present disclosure contemplates that in some instances, this gathered data may include personal information data that uniquely identifies or can be used to contact or locate a specific person. Such personal information data can include demographic data, location-based data, telephone numbers, email addresses, twitter ID&#39;s, home addresses, data or records relating to a user&#39;s health or level of fitness (e.g., vital signs measurements, medication information, exercise information), date of birth, or any other identifying or personal information. As one example, information describing a user of the vehicle may be collected and used to adjust the ride of the vehicle based on user preferences. As another example, the vehicle may include sensors that are used to control operation of the vehicle, and these sensors may obtain information (e.g., still pictures or video images) that can be used to identify persons present in the image. 
     The present disclosure recognizes that the use of such personal information data, in the present technology, can be used to the benefit of users. For example, the personal information data can be used to develop a user profile that describes user comfort levels for certain types of motion of the vehicle. 
     The present disclosure contemplates that the entities responsible for the collection, analysis, disclosure, transfer, storage, or other use of such personal information data will comply with well-established privacy policies and/or privacy practices. In particular, such entities should implement and consistently use privacy policies and practices that are generally recognized as meeting or exceeding industry or governmental requirements for maintaining personal information data private and secure. Such policies should be easily accessible by users and should be updated as the collection and/or use of data changes. Personal information from users should be collected for legitimate and reasonable uses of the entity and not shared or sold outside of those legitimate uses. Further, such collection/sharing should occur after receiving the informed consent of the users. Additionally, such entities should consider taking any needed steps for safeguarding and securing access to such personal information data and ensuring that others with access to the personal information data adhere to their privacy policies and procedures. Further, such entities can subject themselves to evaluation by third parties to certify their adherence to widely accepted privacy policies and practices. In addition, policies and practices should be adapted for the particular types of personal information data being collected and/or accessed and adapted to applicable laws and standards, including jurisdiction-specific considerations. For instance, in the US, collection of or access to certain health data may be governed by federal and/or state laws, such as the Health Insurance Portability and Accountability Act (HIPAA); whereas health data in other countries may be subject to other regulations and policies and should be handled accordingly. Hence different privacy practices should be maintained for different personal data types in each country. 
     Despite the foregoing, the present disclosure also contemplates embodiments in which users selectively block the use of, or access to, personal information data. That is, the present disclosure contemplates that hardware and/or software elements can be provided to prevent or block access to such personal information data. For example, in the identifying content to be displayed to users, the present technology can be configured to allow users to select to “opt in” or “opt out” of participation in the collection of personal information data during registration for services or anytime thereafter. In another example, users can select not to provide personal data for use in suspension control. In yet another example, users can select to limit the length of time personal data is maintained or entirely prohibit the use and storage of personal data. In addition to providing “opt in” and “opt out” options, the present disclosure contemplates providing notifications relating to the access or use of personal information. For instance, a user may be notified upon downloading an app that their personal information data will be accessed and then reminded again just before personal information data is accessed by the app. 
     Moreover, it is the intent of the present disclosure that personal information data should be managed and handled in a way to minimize risks of unintentional or unauthorized access or use. Risk can be minimized by limiting the collection of data and deleting data once it is no longer needed. In addition, and when applicable, including in certain health related applications, data de-identification can be used to protect a user&#39;s privacy. De-identification may be facilitated, when appropriate, by removing specific identifiers (e.g., date of birth, etc.), controlling the amount or specificity of data stored (e.g., collecting location data a city level rather than at an address level), controlling how data is stored (e.g., aggregating data across users), and/or other methods. 
     Therefore, although the present disclosure broadly covers use of personal information data to implement one or more various disclosed embodiments, the present disclosure also contemplates that the various embodiments can also be implemented without the need for accessing such personal information data. That is, the various embodiments of the present technology are not rendered inoperable due to the lack of all or a portion of such personal information data. For example, customized suspension control can be performed using non-personal information data or a bare minimum amount of personal information, other non-personal information available to the devices, or publicly available information.

Metadata:
Filing Date: 20200416
Publication Date: 20220531
Grant Date: 20220531
Priority Date: 20190603
Inventors: CARTER, TROY A.
DOWLE, JAMES J.
HALL, JONATHAN L.
Assignee: APPLE INC
CPC Classifications: [{"code": "B60G2600/182", "inventive": false, "first": false, "tree": "[]"}, {"code": "B60G2206/427", "inventive": false, "first": false, "tree": "[]"}, {"code": "B60G2202/40", "inventive": false, "first": false, "tree": "[]"}, {"code": "B60G21/055", "inventive": true, "first": true, "tree": "[]"}, {"code": "B60G17/06", "inventive": true, "first": false, "tree": "[]"}, {"code": "B60G17/016", "inventive": true, "first": false, "tree": "[]"}, {"code": "B60G2401/174", "inventive": false, "first": false, "tree": "[]"}, {"code": "B60G2400/10", "inventive": false, "first": false, "tree": "[]"}, {"code": "B60G21/0553", "inventive": true, "first": true, "tree": "[]"}, {"code": "B60G17/016", "inventive": true, "first": false, "tree": "[]"}, {"code": "B60G17/06", "inventive": true, "first": false, "tree": "[]"}, {"code": "B60G21/0553", "inventive": true, "first": true, "tree": "[]"}, {"code": "B60G17/016", "inventive": true, "first": false, "tree": "[]"}, {"code": "B60G17/06", "inventive": true, "first": false, "tree": "[]"}]
Family ID: 81756398