Patent Publication Number: US-2023150323-A1

Title: Wheel suspension system with off-wheel-center arm

Description:
FIELD OF THE INVENTION 
     The present invention relates to the field of suspension systems, and more particularly, to wheel suspension systems. 
     BACKGROUND OF THE INVENTION 
     Vehicles can include a vehicle chassis, suspension system and vehicle wheels. Suspension systems can suspend a vehicle chassis to, for example, maintain a good grip of the vehicle wheels on the road while damping and/or absorbing road shocks and/or impacts. Typically, suspension systems can include suspension arms extending between a bottom portion of the vehicle chassis and vehicle wheels, wherein major portions of suspension arms are positioned external to rims of vehicle wheels. Some suspension systems have suspension arms that extend in a direction that is substantially parallel to vehicle wheel rotation axes. Some suspension systems have suspension arms that extend in a direction that is substantially perpendicular to vehicle wheel rotation axes. 
     SUMMARY OF THE INVENTION 
     Some embodiments of the present invention provide a wheel suspension system including: a wheel interface having a wheel interface axis about which a wheel rotates when connected to the wheel interface; and an arm connected to the wheel interface and rotatable with respect to the wheel interface about a first axis, the arm is connectable to a reference frame of a vehicle and rotatable with respect to the reference frame about a second axis; wherein the first axis and the second axis are offset with respect to the wheel interface axis. 
     In some embodiments, the first axis is offset with respect to the wheel interface axis along at least one axis that is perpendicular to the wheel interface axis. 
     In some embodiments, the second axis is offset with respect to the wheel interface axis along at least one axis that is perpendicular to the wheel interface axis. 
     In some embodiments, the wheel interface axis is between the first axis and the second axis along at least one axis that is perpendicular to the wheel interface axis. 
     In some embodiments, the first axis and the second axis are off-parallel with respect to each other. 
     In some embodiments, at least one of the first axis and the second axis are off-parallel with respect to the wheel interface axis. 
     In some embodiments, the wheel interface axis is movable along a substantially straight line. 
     In some embodiments, the arm and the wheel interface are shaped and sized, and the position of the first axis with respect to the wheel interface axis is set to cause the wheel interface axis to move along a substantially straight line. 
     In some embodiments, the wheel suspension system includes a linkage arm connected to the wheel interface and rotatable with respect to the wheel interface about a third axis, the linkage arm is connectable to the reference frame and rotatable with respect to the reference frame about a fourth axis. 
     In some embodiments, the third axis and the fourth axis are offset with respect to the wheel interface axis. 
     In some embodiments, the linkage arm is shaped and sized and the position of the third axis with respect to the wheel interface axis is set to cause the wheel interface axis to move along a substantially straight line. 
     In some embodiments, a distance between the first axis and the second axis is smaller than a diameter of a rim of a wheel to be assembled to the wheel suspension system. 
     In some embodiments, a distance between the first axis and the second axis is greater than a radius of a rim of a wheel to be assembled to the wheel suspension system. 
     In some embodiments, the arm is positioned in a plane that is substantially parallel to a plane that is perpendicular to the wheel interface axis. 
     In some embodiments, the arm is rotatable in a plane that is substantially perpendicular to the wheel interface axis. 
     In some embodiments, the arm is positioned within a diameter of a rim of a wheel when the wheel is assembled to the wheel suspension system. 
     In some embodiments, a ratio between (i) a distance between the first axis and the second axis, and (ii) a maximal substantially linear travel distance of the wheel interface axis ranges between 40% and 70%. 
     In some embodiments, a ratio between (i) a distance between the first axis and the wheel interface axis and (ii) a distance between the first axis and the second axis ranges between 10% and 55%. 
     In some embodiments, a ratio between (i) a distance between the first axis and the second axis, and (ii) a diameter of a rim of a wheel to be assembled to the wheel suspension system ranges between 50% and 90%. 
     In some embodiments, the wheel suspension system includes a motion restraining unit, wherein the motion restraining unit comprises at least one spring and at least one damper, and wherein the motion restrainer unit interconnecting at least one of the wheel interface and the arm with the reference frame. 
     Some embodiments of the present invention provide a vehicle including two or more wheel suspension systems described hereinabove. 
     Some embodiments of the present invention provide a corner assembly including: a sub-frame to connect the corner assembly to a reference frame of a vehicle; a wheel interface having a wheel interface axis; a wheel hub connected to the wheel interface and rotatable with respect to the wheel interface about the wheel interface axis, wherein the wheel interface axis is an axis about which the wheel rotates when connected to the wheel hub; and an arm connected to the wheel interface and rotatable with respect to the wheel interface about a first axis, the arm is connectable to the sub-frame and rotatable with respect to the sub-frame about a second axis; wherein the first axis and the second axis are offset with respect to the wheel interface axis. 
     In some embodiments, the corner assembly includes a brake unit, the braking unit includes: a braking disc connected to the wheel hub, and a braking actuator connected to the wheel interface and acting on the braking disc. 
     In some embodiments, the corner assembly includes a powertrain unit, the powertrain unit includes a drivetrain shaft connected to the wheel hub to rotate the wheel hub about the wheel interface axis. 
     In some embodiments, the powertrain unit includes a motor for generating rotations, wherein the motor is coupled to the drivetrain shaft to rotate the drivetrain shaft. 
     In some embodiments, the drivetrain shaft and the motor are positioned between the wheel interface and the sub-frame. 
     In some embodiments, the motor is connected to the sub-frame. 
     Some embodiments of the present invention provide a vehicle including two or more corner assemblies described hereinabove. 
     Some embodiments of the present invention provide a wheel suspension system including: a wheel interface having a wheel interface axis about which a wheel rotates when connected to the wheel interface; and an arm connected to the wheel interface and rotatable with respect to the wheel interface about a first axis, the arm is connectable to a reference frame and rotatable with respect to the reference frame about a second axis; wherein the first axis and the second axis are off-parallel. 
     In some embodiments, the first axis is parallel to the wheel interface axis. 
     In some embodiments, the second axis is off-parallel with respect to the wheel interface axis. 
     In some embodiments, the wheel suspension system includes a linkage arm connected to the wheel interface and rotatable with respect to the wheel interface about a third axis, the linkage arm is connectable to the reference frame and rotatable with respect to the reference frame about a fourth axis. 
     In some embodiments, the third axis and the fourth axis are offset with respect to the wheel interface axis. 
     In some embodiments, the linkage arm is shaped and sized and the position of the third axis with respect to the wheel interface axis is set to cause the wheel interface axis to move along a substantially straight line. 
     In some embodiments, the wheel suspension system includes a motion restraining unit, wherein the motion restraining unit comprises at least one spring and at least one damper, and wherein the motion restrainer unit interconnecting at least one of the wheel interface and the arm with the reference frame. 
     Some embodiments of the present invention provide a vehicle including two or more wheel suspension systems described hereinabove. 
     Some embodiments of the present invention provide a corner assembly including: a sub-frame to connect the corner assembly to a reference frame of a vehicle; a wheel interface having a wheel interface axis; a wheel hub connected to the wheel interface and rotatable with respect to the wheel interface about the wheel interface axis, wherein the wheel interface axis is an axis about which the wheel rotates when connected to the wheel hub; and an arm connected to the wheel interface and rotatable with respect to the wheel interface about a first axis, the arm is connectable to the sub-frame and rotatable with respect to the sub-frame about a second axis; wherein the first axis and the second axis are off-parallel. 
     In some embodiments, the corner assembly includes a brake unit, the braking unit includes: a braking disc connected to the wheel hub, and a braking actuator connected to the wheel interface and acting on the braking disc. 
     In some embodiments, the corner assembly includes a powertrain unit, the powertrain unit includes a drivetrain shaft connected to the wheel hub to rotate the wheel hub about the wheel interface axis. 
     In some embodiments, the powertrain unit comprises a motor for generating rotations, wherein the motor is coupled to the drivetrain shaft to rotate the drivetrain shaft. 
     In some embodiments, the drivetrain shaft and the motor are positioned between the wheel interface and the sub-frame. 
     In some embodiments, the motor is connected to the sub-frame. 
     Some embodiments of the present invention provide a vehicle including two or more corner assemblies described hereinabove. 
     These, additional, and/or other aspects and/or advantages of the present invention are set forth in the detailed description which follows; possibly inferable from the detailed description; and/or learnable by practice of the present invention. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       For a better understanding of embodiments of the invention and to show how the same can be carried into effect, reference will now be made, purely by way of example, to the accompanying drawings in which like numerals designate corresponding elements or sections throughout. 
       In the accompanying drawings: 
         FIGS.  1 A and  1 B  are schematic illustrations of a wheel suspension system, according to some embodiments of the invention; 
         FIGS.  2 A and  2 B  are schematic illustrations of a wheel suspension system including a motion restraining unit, according to some embodiments of the invention; 
         FIG.  3    is a schematic illustration of a corner assembly including a wheel suspension system including a sub-frame, according to some embodiments of the invention; 
         FIG.  4    which is a schematic illustration of a corner assembly including a wheel suspension system and a powertrain unit, according to some embodiments of the invention; 
         FIG.  5    is a schematic illustration of a corner assembly including a wheel suspension system and a braking unit, according to some embodiments of the invention; 
         FIG.  6    is a schematic illustration of a corner assembly including a wheel suspension system with a motion restraining unit, a drivetrain shaft and a braking unit, and of a wheel assembled to the wheel suspension system, according to some embodiments of the invention; 
         FIG.  7    is a schematic illustration of a corner assembly including a wheel suspension system with a motion restraining unit, a sub-frame and a braking unit, and of a wheel assembled to the wheel suspension system, according to some embodiments of the invention; and 
         FIGS.  8 A,  8 B and  8 C  are schematic illustrations of a wheel suspension system, according to some embodiments of the invention. 
     
    
    
     It will be appreciated that, for simplicity and clarity of illustration, elements shown in the figures have not necessarily been drawn to scale. For example, the dimensions of some of the elements can be exaggerated relative to other elements for clarity. Further, where considered appropriate, reference numerals can be repeated among the figures to indicate corresponding or analogous elements. 
     DETAILED DESCRIPTION OF THE INVENTION 
     In the following description, various aspects of the present invention are described. For purposes of explanation, specific configurations and details are set forth in order to provide a thorough understanding of the present invention. However, it will also be apparent to one skilled in the art that the present invention can be practiced without the specific details presented herein. Furthermore, well known features can have been omitted or simplified in order not to obscure the present invention. With specific reference to the drawings, it is stressed that the particulars shown are by way of example and for purposes of illustrative discussion of the present invention only and are presented in the cause of providing what is believed to be the most useful and readily understood description of the principles and conceptual aspects of the invention. In this regard, no attempt is made to show structural details of the invention in more detail than is necessary for a fundamental understanding of the invention, the description taken with the drawings making apparent to those skilled in the art how the several forms of the invention can be embodied in practice. 
     Before at least one embodiment of the invention is explained in detail, it is to be understood that the invention is not limited in its application to the details of construction and the arrangement of the components set forth in the following description or illustrated in the drawings. The invention is applicable to other embodiments that can be practiced or carried out in various ways as well as to combinations of the disclosed embodiments. Also, it is to be understood that the phraseology and terminology employed herein is for the purpose of description and should not be regarded as limiting. 
     Suspension systems can suspend a vehicle chassis to maintain a good grip of vehicle wheels on the road while damping and/or absorbing road shocks and/or impacts. Various embodiments of the present invention can include wheel suspension systems having one or more suspension arms positioned within a diameter of a rim of a wheel when the wheel is, for example, assembled to the wheel suspensions system. Such wheel suspension systems have several advantages over typical suspension systems having suspension arms positioned external to the rim of the wheel. For example, wheel suspension systems can reduce the weight of the vehicle chassis as compared to typical suspension systems, while providing competitive suspension performance parameters. Wheel suspension systems of the present invention can, for example, dampen each wheel separately such that the dampening of one wheel does not cause a dampening effect on other wheels of the vehicle. Wheel suspension systems of the present invention can, for example, free a significant space beneath, in front, or back of the vehicle chassis or wheel corner as compared to typical suspension systems. 
     Reference is now made to  FIGS.  1 A and  1 B , which are schematic illustrations of a wheel suspension system  100 , according to some embodiments of the invention. 
     According to some embodiments of the invention, wheel suspension system  100  includes a wheel interface  110  and an arm  120 . 
     Wheel interface  110  can connect to a wheel. Wheel interface  110  can have a wheel interface axis  112  about which the wheel can rotate when assembled to wheel interface  110 . Wheel interface  110  can have a wheel interface plane  114  in which the wheel can rotate when the wheel is assembled to wheel interface  110 . 
     In some embodiments, wheel suspension system  100  includes a wheel hub  116  connected to wheel interface  110  and rotatable about wheel interface axis  112 . Wheel hub  116  can connect to the wheel. 
     Arm  120  can be connected to wheel interface  110  and can be rotatable with respect to wheel interface  110  about a first axis  191   a.  In some embodiments, arm  120  is connected to wheel interface  110  at its first end  121 . In some embodiments, arm  120  is connected to wheel interface  110  using a first pivoting connection  191 . 
     In some embodiments, arm  120  is connectable to a reference frame of a vehicle and rotatable with respect to the reference frame about a second axis  192   a.  The reference frame may be, for example, a vehicle chassis, a vehicle platform, etc. In some embodiments, arm  120  is connectable to the reference frame at its second end  122 . In some embodiments, arm  120  is connectable to the reference frame using a second pivoting connection  192 . 
     First axis  191   a  can be offset with respect to wheel interface axis  112 . First axis  191   a  can be offset with respect to wheel interface axis  112  along one or more axes that are perpendicular (or substantially perpendicular) to wheel interface axis  112 . In some embodiments, first axis  191   a  is offset with respect to wheel interface axis  112  along an axis  115   a  that is parallel (or substantially parallel) to a vehicle longitudinal axis (not shown) when wheel suspension system is assembled to the vehicle. In some embodiments, first axis  191   a  is offset with respect to wheel interface axis  112  along an axis  115   b  that is parallel (or substantially parallel) to a vehicle vertical axis when wheel suspension system  100  is assembled to the vehicle. In some embodiments, first axis  191   a  is offset with respect to wheel interface axis  112  along axis  115   a  that is substantially parallel to the vehicle longitudinal axis and along axis  115   b  that is parallel (or substantially parallel) to the vehicle vertical axis when wheel suspension system  100  is assembled to the vehicle (e.g., as shown in  FIGS.  1 A and  1 B ). 
     In some embodiments, wheel interface  110  is shaped to cause the offset of first axis  191   a  with respect to wheel interface axis  112 . For example, wheel interface  110  may include an extended portion  111  that may extend radially away from wheel interface axis  112  and may include first axis  191   a  (e.g., as shown in  FIGS.  1 A and  1 B ). In this manner, first axis  191   a  can be distanced from wheel interface axis  112  and not co-located therewith. In some embodiments, first axis  191   a  is offset with respect to wheel interface axis  112  along one or more axes perpendicular to wheel interface axis  112  (e.g., such as axes  115   a,    115   b ) and towards a contact surface of the wheel with the ground when the wheel is assembled to wheel suspension system  100  (e.g., as shown in and described below with respect to  FIGS.  6  and  7   ). 
     In some embodiments, arm  120  is shaped to cause the offset of first axis  191   a  with respect to wheel interface axis  112 . For example, arm  120  can include an extended portion extending transversally to a general direction of arm  120 . Yet, in this example, the transversally extended portion of arm  120  can be coupled to wheel interface  110  such that first axis  191   a  is positioned at a distance from an end of the transversally extended portion thereof. 
     In some embodiments, wheel suspension system  100  includes an offset linkage. The offset linkage can interconnect wheel interface  110  with, for example, first end  121  of arm  120 . In this manner, first end  121  of arm  120  can be assembled at a distance from wheel interface axis  112  by positioning first axis  191   a  (and first pivoting connection  191 ) at the offset linkage. 
     Second axis  192   a  can be offset with respect to wheel interface axis  112 . Second axis  192   a  can be offset with respect to wheel interface axis  112  along one or more axes that are perpendicular (or substantially perpendicular) to wheel interface axis  112 . In some embodiments, second axis  192   a  is offset with respect to wheel interface axis  112  along axis  115   a  that is parallel (or substantially parallel) to the vehicle longitudinal axis when wheel suspension system  100  is assembled to the vehicle. In some embodiments, second axis  192   a  is offset with respect to wheel interface axis  112  along axis  115   b  that is parallel (or substantially parallel) to the vehicle vertical axis when wheel suspension system  100  is assembled to the vehicle. In some embodiments, second axis  192   a  is offset with respect to wheel interface axis  112  along axis  115   a  that is parallel (or substantially parallel) to the vehicle longitudinal axis and along axis  115   b  that is parallel (or substantially parallel) to the vehicle vertical axis when wheel suspension system  100  is assembled to the vehicle (e.g., as shown in  FIGS.  1 A and  1 B ). 
     In some embodiments, wheel interface axis  112  is positioned between first axis  191   a  and second axis  191   b  (e.g., as shown in  FIGS.  1 A and  1 B ). In some embodiments, wheel interface axis  112  is positioned between first axis  191   a  and second axis  191   b  along axis  115   a  that is parallel (or substantially parallel) to the vehicle longitudinal axis when wheel suspension system  100  is assembled to the vehicle. In some embodiments, wheel interface axis  112  is positioned between first axis  191   a  and second axis  191   b  along axis  115   b  that is parallel (or substantially parallel) to the vehicle vertical axis when wheel suspension system  100  is assembled to the vehicle. In some embodiments, wheel interface axis  112  is positioned between first axis  191   a  and second axis  191   b  along axis  115   a  that is parallel (or substantially parallel) to the vehicle longitudinal axis and along axis  115   b  that is parallel (or substantially parallel) to the vehicle vertical axis when wheel suspension system  100  is assembled to the vehicle (e.g., as shown in  FIGS.  1 A and  1 B ). 
     In some embodiments, first axis  191   a  is parallel (or substantially parallel) to wheel interface axis  112 . In some embodiments, first axis  191   a  is off-parallel with respect to wheel interface axis  112 . 
     In some embodiments, second axis  192   a  is parallel (or substantially parallel) to wheel interface axis  112 . In some embodiments, second axis  192   a  is off-parallel with respect to wheel interface axis  112 . 
     In some embodiments, second axis  192   a  and first axis  191   a  are off-parallel (e.g., second axis  192   a  and first axis  191   a  are non-parallel). This can, for example, enable setting a dynamic toe angle and/or a dynamic camber angle in wheel suspension system  100 . 
     In various embodiments, first pivoting connection  191  and/or second pivoting connection  192  can include at least one of: one or more bushings, one or more bearings, and one or more spherical joints. In various embodiments, first pivoting connection  191  can include two connection points  121   a,    121   b  and/or second pivoting connection  192  can include two connection points  122   a,    122   b.  This can, for example, increase structural rigidity of first and second pivoting connections  191 ,  192 . This can, for example, increase loads that arm  120  and first and second pivoting connections  191 ,  192  can sustain (e.g., side loads applied by the wheel when the wheel is assembled to wheel suspension system  100 ). 
     In some embodiments, arm  120  is rotatable in a plane that is parallel (or substantially parallel) to wheel interface plane  114 . In some embodiments, arm  120  extends longitudinally in a general direction of a plane that is parallel (or substantially parallel) to wheel interface plane  114 . 
     In some embodiments, wheel interface  110  and arm  120  are shaped and sized, and the position of first axis  191   a  with respect to wheel interface axis  112  is set to cause a linear motion (or substantially linear motion) of wheel interface axis  112 . In some embodiments, wheel interface  110  and arm  120  are shaped and sized, and the position of first axis  191   a  with respect to wheel interface axis  112  is set to cause a linear motion (or substantially linear motion) of wheel interface axis  112  along axis  115   b  that is parallel (or substantially parallel) to the vehicle vertical axis when wheel suspension system  100  is assembled to the vehicle. 
     In some embodiments, wheel interface axis  112  is movable along a substantially straight line. In some embodiments, wheel interface axis  112  is movable along a substantially straight line that is parallel to the vehicle vertical axis when wheel suspension system  100  is assembled to the vehicle. In some embodiments, wheel interface  110  and arm  120  are shaped and sized, and the position of first axis  191   a  with respect to wheel interface axis  112  is set to cause wheel interface axis  112  to move along a substantially straight line. 
     In some embodiments, arm  120  is positioned within a diameter of the rim of the wheel when the wheel is assembled to wheel suspension system  100 . In some embodiments, arm  120  is shaped and sized to be positioned within a diameter of the rim of the wheel when the wheel is assembled to wheel suspension system  100  (e.g., without radially protruding external thereto). In some embodiments, arm  120  has a curved, e.g., substantially arc-like shape. In some embodiments, the length of arm  120  is smaller than the diameter of the rim of the wheel to be assembled to wheel suspension system  100 . In some embodiments, the length of arm  120  is greater than a radius of the rim of the wheel to be assembled to wheel suspension system  100 . In various embodiments, offsetting first axis  191   a  and second axis  192   a  enables arm  120  to be positioned within a diameter of the rim of the wheel when the wheel is assembled to wheel suspension system  100 . 
     In some embodiments, at least one of: a shape of arm  120 , a length of arm  120  and a distance between first axis  191   a  and second axis  192   a  are set based on a diameter of the rim of the wheel to be assembled to wheel suspension system  100  to provide a desired maximal substantially linear travel distance of wheel interface axis  112 . 
     In some embodiments, a ratio between (i) the distance between first axis  191   a  and second axis  192   a  and (ii) the desired maximal substantially linear travel distance of wheel interface  110 /wheel interface axis  112  ranges between 40% and 70%. 
     In some embodiments, a ratio between (i) the distance between first axis and wheel interface axis  112  and (ii) the distance between first axis  191   a  and second axis  192   a  ranges between 10% and 55%. 
     In some embodiments, a ratio between (i) the distance between first axis  191   a  and second axis  192   a  and (ii) the diameter of the rim of the wheel to be assembled to wheel suspension system  100  ranges between 50% and 90%. 
     In some embodiments, a width of wheel suspension system  100  is a maximal distance between an inner lateral surface of arm  120  (e.g., surface that faces the reference frame of the vehicle) and an outer surface of wheel interface  110  (e.g., surface that faces the wheel). In some embodiments, the width of wheel suspension system  100  ranges between 20% and 60% (e.g., 25% to 40%) of the maximal substantially linear travel distance of wheel interface axis  112 . 
     Such ratios can, for example, provide a compact arm  120  that can be positioned within the rim of the wheel when the wheel is connected to wheel suspension system  100  and provide substantially the same maximal travel distance of wheel interface  110 /wheel interface axis  112  as a maximal travel distance thereof in typical suspension systems having suspension arms outside the rim of the wheel, even though arm  120  of wheel suspension  110  can be significantly shorter than suspension arms of typical suspension systems. 
     For example, for a rim having an outer diameter of 16 inches (e.g., ˜406.4 mm), a maximal substantially linear travel distance of wheel interface axis  112  can range between 120 mm and 180 mm (e.g., between 140 mm and 160 mm). Yet, in this example, the distance between first axis  191   a  and second axis  191   b  can range between 200 mm and 300 mm. Yet, in this example, the width of wheel suspension system  100  can range between 25 mm and 70 mm (e.g., between 35 mm and 50 mm). 
     Configuring arm  120  to rotate in a plane that is parallel (or substantially parallel) to wheel interface plane  114  and configuring arm  120  to be positioned within the diameter of the rim of the wheel (e.g., as described hereinabove) can provide a compact wheel suspension system  100 . Wheel suspension system  100  can, for example, eliminate a need in positioning and/or extending different components of wheel suspension system  100  beneath/above/into a vehicle chassis, without reducing (or substantially without reducing) a maximal substantially linear travel distance of wheel interface  110 /wheel interface axis  112  with respect to the reference frame of the vehicle. 
     Offsetting first axis  191   a  with respect to wheel interface axis  112  in wheel suspension  110  can enable substantially the same maximal travel distance of wheel interface  110 /wheel interface axis  112  as a maximal travel distance thereof in typical suspension systems having suspension arms outside the rim of the wheel, even though arm  120  of wheel suspension  110  can be significantly shorter than suspension arms of typical suspension systems. 
     In some embodiments, wheel suspension system  100  can include a linkage arm  130 . Linkage arm  130  can be connected to wheel interface  110  and can be rotatable with respect to wheel interface about a third axis  193   a.  In some embodiments, linkage arm  130  is connected to wheel interface  130  using a third pivoting connection  193 . In some embodiments, linkage arm  130  is connected to wheel interface  130  at its first end  131 . 
     Linkage arm  130  can be connectable to the reference frame of the vehicle and rotatable with respect to the reference frame about a fourth axis  194   a.  In some embodiments, linkage arm  130  is connectable to the reference frame using a fourth pivoting connection  194 . In some embodiments, linkage arm  130  is connectable to the reference frame at its second end  132 . 
     In some embodiments, third axis  193   a  is offset with respect to wheel interface axis  112  along axis  115   b  that is parallel (or substantially parallel) to the vehicle vertical axis when wheel suspension system  100  is assembled to the vehicle. In some embodiments, third axis  193  is aligned (or substantially aligned) with wheel interface axis  112  along axis  115   b  that is parallel (or substantially parallel) to the vehicle vertical axis when wheel suspension system  100  is assembled to the vehicle. In some embodiments, wheel interface axis  112  is between first axis  191   a  and third axis  193   a  along axis  115   b  that is parallel (or substantially parallel) to the vehicle vertical axis when wheel suspension system  100  is assembled to the vehicle. 
     In some embodiments, fourth axis  194   a  is offset with respect to wheel interface axis  112  along axis  115   a  that is parallel (or substantially parallel) to the vehicle longitudinal axis and along axis  115   b  that is parallel (or substantially parallel) to the vehicle vertical axis when wheel suspension system is assembled to the vehicle (e.g., as shown in  FIGS.  1 A and  1 B ). In some embodiments, second axis  192   a  is between fourth axis  194   a  and wheel interface axis  112  along axis  115   a  that is parallel (or substantially parallel) to the vehicle longitudinal axis when wheel suspension system is assembled to the vehicle (e.g., as shown in  FIGS.  1 A and  1 B ). In some embodiments, third axis  193   a  is between fourth axis  194   a  and wheel interface axis  112  along axis  115   b  that is parallel (or substantially parallel) to the vehicle vertical axis when wheel suspension system is assembled to the vehicle (e.g., as shown in  FIGS.  1 A and  1 B ). 
     In some embodiments, third pivoting connection  193  includes at least one of: one or more bushings and one or more spherical joints. In some embodiments, fourth pivoting connection  194  includes at least one of: one or more bushings and one or more spherical joints. Bushing(s) and/or spherical joint(s) can cause third axis  193   a  and/or fourth axis  194   a  to change their orientation with respect to wheel interface axis  112  when wheel interface  110  moves (e.g., to prevent over restraining of wheel suspension  100 ). 
     Linkage arm  130  can, for example, restrict motion of wheel interface  110 . For example, linkage arm  130  can close one or more degrees of freedom of wheel interface  110  to cause wheel interface  110  to move in a plane that is parallel (or substantially parallel) to wheel interface plane  114  and eliminate, or substantially eliminate, motion of wheel interface  110  in other planes. Linkage arm  130  may, for example, constrain the rotation of wheel interface  110  about first axis  191   a.    
     In various embodiments, linkage arm  130  causes a substantially linear motion of wheel interface axis  112  and/or causes wheel interface axis  112  to move along a substantially straight line. For example, linkage arm  130  can be shaped and sized, and the position of third axis  193   a  with respect to wheel interface axis  112  can be set to cause a substantially linear motion of wheel interface axis  112  and/or to cause wheel interface axis  112  to move along a substantially straight line (e.g., additionally or complementary, to features described hereinabove as causing the substantially linear motion). For example, offsetting third axis  193   a  with respect to wheel interface axis  112  (e.g., as shown in  FIGS.  1 A and  1 B ) can constrain the rotation of wheel interface  110  about first axis  191   a  so as to cause a substantially linear motion of wheel interface axis  112  and/or to cause wheel interface axis  112  to move along a substantially straight line. 
     In some embodiments, linkage arm  130  has a curved shape. In some embodiments, linkage arm  130  is curved in two perpendicular planes (e.g., one of which is parallel to wheel interface plane  114 ). 
     The substantially linear motion of wheel interface axis  112  of wheel suspension system  100  can slightly vary from a straight line that is parallel to the vehicle vertical axis. For example, wheel interface axis  112  can move along an arc-like path wherein a maximal distance between the arc-like path and the straight line parallel to the vehicle vertical axis can range between 10-30% of the maximal wheel interface  110  travel distance. For example, a maximal wheel interface  110  travel distance of 130 mm, the maximal distance between the arc-like path and the straight line parallel to the vehicle vertical axis can be 30 mm. This variation of substantially linear motion of wheel interface axis  112  of wheel suspension system  100  from the straight line that is parallel to the vehicle vertical axis is similar to variation in typical suspension systems having suspension trailing or leading arms extending outside the rim of the wheel, even though arm  120  of wheel suspension  110  can be significantly shorter than suspension arms of these typical trailing or leading arms suspension systems. 
     Reference is now made to  FIGS.  2 A and  2 B , which are schematic illustrations of a wheel suspension system  100  including a motion restraining unit  140 , according to some embodiments of the invention. 
     In some embodiments, wheel suspension system  100  includes a motion restraining unit  140 . Motion restraining unit  140  can include at least one damper  142  and at least one spring  144 . In some embodiments, motion restraining unit  140  includes a spring damper (e.g., as shown in  FIG.  3 A ). In some embodiments, damper  142  and spring  144  are spatially separated (e.g., shown in  FIG.  3 B ). 
     Motion restraining unit  140  can interconnect at least one of: wheel interface  110  and arm  120 , with at least one of: the reference frame of the vehicle and a sub-frame of a corner assembly (e.g., sub-frame  205  of corner assembly  200  as described below with respect to  FIG.  2   ). For example, motion restrainer unit  140  can be connected to wheel interface  110  and arm  120  using first pivoting connection  191  (e.g., as shown in  FIGS.  2 A and  2 B ). Other connections are also possible. 
     Reference is now made to  FIG.  3   , which is a schematic illustration of a corner assembly  200  including a wheel suspension system  100  and a sub-frame  205 , according to some embodiments of the invention. 
     According to some embodiments of the invention, corner assembly  200  includes a sub-frame  205  and wheel suspension system  100 . 
     Sub-frame  205  can be a structural element can that connects corner assembly  200  to the reference frame of the vehicle. In some embodiments, arm  120  of wheel suspension system  100  is connected to sub-frame  205  (e.g., using second pivoting connection  192 ) and rotatable with respect to sub-frame  205  about second axis  192   a.  In some embodiments, linkage arm  130  is connected to sub-frame  205  (e.g., using fourth pivoting connection  194 ) and rotatable with respect to sub-frame  205  about fourth axis  194   a.    
     Reference is now made to  FIG.  4   , which is a schematic illustration of a corner assembly  300  including a wheel suspension system  100 , a sub-frame  305  and a powertrain unit  350 , according to some embodiments of the invention. 
     According to some embodiments of the invention, corner assembly  200  includes wheel suspension system  100  (e.g., as described above with respect to  FIGS.  1 A and  1 B , and  FIGS.  2 A and  2 B ), a sub-frame  305  and a powertrain unit  350 . 
     Sub-frame  305  is schematically shown in  FIG.  4    as dashed rectangular. Sub-frame  305  can have different shapes and dimensions. For example, sub-frame  305  can be similar to sub-frame  205  described above and shown in  FIG.  3   . Wheel suspension system  100  can be connected to sub-frame  305  (e.g., as described above with respect to  FIG.  3   ). 
     In some embodiments, powertrain unit  350  includes a drivetrain shaft  352 . Drivetrain shaft  352  can be connected to wheel hub  116  of wheel suspension system  100  and can rotate wheel hub  116  while enabling the substantially linear motion of wheel interface axis  112 . Drivetrain shaft  352  can extend between sub-frame  305  and wheel hub  116  through wheel suspension system  100 . Drivetrain shaft  352  can, for example, restrict motion of wheel interface  110  by, for example, closing one or more degrees of freedom of wheel interface  110 . 
     In some embodiments, powertrain unit  350  includes a motor  354  for generating rotational motions. Motor  354  can be coupled to the drivetrain shaft  352  to rotate drivetrain shaft  352 . In some embodiments, motor  354  is positioned within a volume defined by wheel suspension system  100 . For example, motor  354  can be positioned within a volume between sub-frame  305  and wheel interface  310  of wheel suspension unit  100 . In some embodiments, motor  354  is connected to sub-frame  305 . In some embodiments, motor  354  is an electrical motor. 
     In some embodiments, powertrain unit  350  includes a transmission sub-unit for transferring the rotational motions from motor  354  to drivetrain shaft  352 . The transmission sub-unit can include at least one of: one or more gears, and one or more transmission belts, etc. 
     An advantage of wheel suspension system  100  having first axis  191   a  offset with respect to wheel interface axis  112  can be a space formed in wheel suspension system  100  that can be used, e.g., for extending a drivetrain shaft  352  through wheel suspension system  100  and/or for locating components of powertrain unit  350  within such space. 
     Reference is now made to  FIG.  5   , which is a schematic illustration of a corner assembly  400  including a wheel suspension system  100 , a sub-frame  405  and a braking unit  460 , according to some embodiments of the invention. 
     According to some embodiments of the invention, corner assembly  400  includes wheel suspension system  100  (e.g., described hereinabove with respect to  FIGS.  1 A and  1 B , and  FIGS.  2 A and  2 B ), a sub-frame  405  (e.g., such as sub-frame  205  or  305  described hereinabove) and a braking unit  460 . 
     Braking unit  460  can include a braking disc  462  and a breaking actuator  464 . Braking disc  462  can be connected to wheel hub  116  of wheel suspension system  100 . Braking actuator  464  can be connected to, for example, wheel interface  110  of wheel suspension system  100  and can embrace braking disc  162  and act on braking disc  162 . Braking actuator  164  can be, for example, a caliper. 
     Reference is now made to  FIG.  6   , which is a schematic illustration of a corner assembly  500  including a wheel suspension system  100 , with a motion restraining unit  140 , a drivetrain shaft  352  and a braking unit  460 , and of a wheel  90  assembled to wheel suspension system  100 , according to some embodiments of the invention. 
     Reference is also made to  FIG.  7   , which is a schematic illustration of a corner assembly  600  including a wheel suspension system  100  with a motion restraining unit  140 , a sub-frame  605 , and a braking unit  460  and of a wheel  90  assembled to wheel suspension system  100 , according to some embodiments of the invention. 
     In some embodiments, the length of arm  120  of wheel suspension system  100  is smaller than the diameter of the rim of wheel  90  to be assembled to wheel suspension system  100  such that entire arm  120  can be positioned within the rim without radially protruding external thereto. In some embodiments, the length of arm  120  of wheel suspension system  100  is greater than the radius of the rim of wheel  90  to be assembled to wheel suspension system  100 . 
     In some embodiments, a ratio between (i) the distance between first axis  191   a  and second axis  192   a  in wheel suspension system  100  and (ii) the diameter of the rim of wheel  90  to be assembled to wheel suspension system  100  ranges between 50% and 90%. 
     In some embodiments, a ratio between (i) the distance between first axis  191   a  and second axis  192   a  and (ii) the desired maximal substantially linear travel distance of wheel interface  110 /wheel interface axis  112  ranges between 40% and 70%. 
     In some embodiments, a ratio between (i) the distance between first axis and wheel interface axis  112  and (ii) the distance between first axis  191   a  and second axis  192   a  ranges between 10% and 55%. 
     Such ratios can, for example, provide a compact arm  120  that can be positioned within the rim of wheel  90  when wheel  90  is connected to wheel suspension system  100  (e.g., as shown in  FIGS.  6  and  7   ) and provide substantially the same maximal travel distance of wheel interface  110 /wheel interface axis  112  as a maximal travel distance thereof in typical suspension systems having suspension arms outside the rim of the wheel, even though arm  120  of wheel suspension  110  can be significantly shorter than suspension arms of typical suspension systems. 
     In some embodiments, a width of wheel suspension system  100  is a maximal distance between an inner lateral surface of arm  120  (e.g., surface that faces sub-frame  605 /the reference frame of the vehicle) and an outer surface of wheel interface  110  (e.g., surface that faces wheel  90 ). In some embodiments, the width of wheel suspension system  100  ranges between 20% and 60% (e.g., 25% to 40%) of the maximal substantially linear travel distance of wheel interface axis  112 . 
     In some embodiments, first axis  191   a  is offset with respect to wheel interface axis  112  along one or more axes perpendicular to wheel interface axis  112  of wheel suspension system  100  and towards a contact surface  80  of wheel  90  with the ground (e.g., as shown in  FIGS.  6  and  7   ). 
     Reference is now made to  FIGS.  8 A,  8 B and  8 C , which are schematic illustrations of a wheel suspension system  700 , according to some embodiments of the invention. 
     According to some embodiments of the invention, wheel suspension system  700  includes a wheel interface  710  and an arm  720 . 
     Wheel interface  710  can connect a wheel thereto. Wheel interface  710  can have a wheel interface axis  712  about which the wheel can rotate when connected to wheel interface  710 . Wheel interface  710  can have a wheel interface plane  714  in which the wheel can rotate when the wheel is connected to wheel interface  710 . 
     In some embodiments, wheel suspension system  700  includes a wheel hub  716  connected to wheel interface  710  and rotatable about wheel interface axis  712 . Wheel hub  716  can connect the wheel thereto. 
     Arm  720  can be connected to wheel interface  710  and can be rotatable with respect to wheel interface  710  about a first axis  791   a.  In some embodiments, arm  720  is connectable to the reference frame at its second end  721 . In some embodiments, arm  720  is connected to wheel interface  710  using a first pivoting connection  791 . First pivoting connection  791  is schematically shown in  FIG.  8 A  and not shown in  FIGS.  8 B and  8 C  for sake of clarity. 
     In some embodiments, arm  720  is connectable to the reference frame of the vehicle and rotatable with respect to the reference frame about a second axis  792   a.  In some embodiments, arm  720  is connectable to the reference frame at its second end  722 . In some embodiments, arm  720  is connectable to the reference frame using a second pivoting connection  792 . Second pivoting connection  792  is schematically shown in  FIG.  8 A  and not shown in  FIGS.  8 B and  8 C  for sake of clarity. 
     First axis  791   a  and second axis  792   a  can be off-parallel (e.g., non-parallel with respect to each other). For example, as shown in  FIGS.  8 A,  8 B and  8 C . This can, for example, enable setting a dynamic toe angle and/or a dynamic camber angle in wheel suspension system  100 . In some embodiments, first axis  791   a  and second axis  792   b  are off-parallel with respect to wheel interface axis  712 . 
     In some embodiments, first axis  791   a  is parallel (or substantially parallel) to wheel interface axis  712 . In some embodiments, first axis  791   a  is off-parallel to wheel interface axis  712 . 
     In some embodiments, second axis  792   a  is parallel (or substantially parallel) to wheel interface axis  712 . In some embodiments, second axis  792   a  is off-parallel to wheel interface axis  712 . In some embodiments, wheel interface axis  712  is movable along substantially a straight line (e.g., as described hereinabove). 
     In some embodiments, wheel suspension system  700  includes a linkage arm  730  (e.g., like linkage arm  130  described hereinabove). 
     Linkage arm  730  can be connected to wheel interface  710  and can be rotatable with respect to wheel interface  710  about a third axis  793   a.  In some embodiments, linkage arm  730  is connected to wheel interface  730  using a third pivoting connection  793 . Third pivoting connection  793  is schematically shown in  FIG.  8 A  and not shown in  FIGS.  8 B and  8 C  for sake of clarity. 
     Linkage arm  730  can be connectable to the reference frame of the vehicle and rotatable with respect to the reference frame about a fourth axis  794   a.  In some embodiments, linkage arm  130  is connectable to the reference frame using a fourth pivoting connection  794 . Fourth pivoting connection  794  is schematically shown in  FIG.  8 A  and not shown in  FIGS.  8 B and  8 C  for sake of clarity. 
     In some embodiments, third axis  793   a  is offset with respect to wheel interface axis  712  along axis  715   b  that is parallel (or substantially parallel) to the vehicle vertical axis when wheel suspension system  700  is assembled to the vehicle. In some embodiments, third axis  793   a  is aligned (or substantially aligned) with wheel interface axis  712  along axis  715   b  that is parallel (or substantially parallel) to the vehicle vertical axis when wheel suspension system  700  is assembled to the vehicle. 
     In some embodiments, wheel interface axis  712  is between first axis  791   a  and third axis  793   a  along axis  715   b  that is parallel (or substantially parallel) to the vehicle vertical axis when wheel suspension system  700  is assembled to the vehicle. 
     In some embodiments, fourth axis  794   a  is offset with respect to wheel interface axis  712  along axis  715   a  that is parallel (or substantially parallel) to the vehicle longitudinal axis and along axis  715   b  that is parallel (or substantially parallel) to the vehicle vertical axis when wheel suspension system is assembled to the vehicle. 
     In some embodiments, third pivoting connection  793  includes at least one of: one or more bushings and one or more spherical joints. In some embodiments, fourth pivoting connection  794  includes at least one of: one or more bushings and one or more spherical joints. Bushing(s) and/or spherical joint(s) can cause third axis  793   a  and/or fourth axis  794   a  to change their orientation with respect to wheel interface axis  712  when wheel interface  710  moves (e.g., to prevent locking of wheel suspension  700 ). 
     Linkage arm  730  can, for example, restrict motion of wheel interface  710 . For example, linkage arm  730  can close one or more degrees of freedom of wheel interface  710  to cause wheel interface  710  to move in a plane that is parallel (or substantially parallel) to wheel interface plane  714  and eliminate, or substantially eliminate, motion of wheel interface  710  in other planes. Linkage arm  730  may, for example, constrain the rotation of wheel interface  710  about first axis  791   a.    
     In various embodiments, linkage arm  730  causes a substantially linear motion of wheel interface axis  712  and/or causes wheel interface axis  712  to move along a substantially straight line. For example, linkage arm  730  can be shaped and sized, and the position of third axis  793   a  with respect to wheel interface axis  712  can be set to cause a substantially linear motion of wheel interface axis  712  and/or to cause wheel interface axis  712  to move along a substantially straight line. For example, offsetting third axis  793   a  with respect to wheel interface axis  712  (e.g., as shown in  FIGS.  8 A,  8 B and  8 C ) can constrain the rotation of wheel interface  710  about first axis  791   a  so as to cause a substantially linear motion of wheel interface axis  712  and/or to cause wheel interface axis  712  to move along a substantially straight line. 
     In some embodiments, linkage arm  730  has a curved shape. In some embodiments, linkage arm  730  is curved in two perpendicular planes (e.g., one of which is perpendicular to wheel interface axis  712 ). 
     Wheel suspension system  700  can include at least some features of wheel suspension system  100  described hereinabove. For example, at least one of first axis  791   a  and second axis  792   a  can be offset with respect to wheel interface axis  712  along at least one axis that is perpendicular to the wheel interface axis  712  (e.g., as described hereinabove with respect to  FIGS.  1 A and  1 B ). Wheel suspension system  700  can, for example, include a motion restrainer unit (e.g., like motion restrainer unit  140  described above with respect to  FIGS.  1 A and  1 B ). Wheel suspension system  700  can include other features of wheel suspension system  100 . 
     Some embodiments of the present invention can provide a corner assembly including wheel suspension system  700  at least one of: a sub-frame (e.g., such as sub-frame  205  described hereinabove), a powertrain unit (e.g., such as powertrain unit  350  described hereinabove) and a braking unit (e.g., such as braking unit  460  described hereinabove). 
     Some embodiments of the present invention can provide a vehicle including two or more wheel suspension systems described hereinabove (e.g., such as wheel suspension systems  100 ,  700 ). Some embodiments of the present invention can provide a vehicle including two or more vehicles corner modules described hereinabove. In some embodiments, the vehicle can include two or more wheels assembled to the wheel suspension systems. The vehicle can, for example, be a passenger car, a commercial vehicle, a sport utility vehicle, an electrical car, a van, etc. 
     In the above description, an embodiment is an example or implementation of the invention. The various appearances of “one embodiment”, “an embodiment”, “certain embodiments” or “some embodiments” do not necessarily all refer to the same embodiments. Although various features of the invention can be described in the context of a single embodiment, the features can also be provided separately or in any suitable combination. Conversely, although the invention can be described herein in the context of separate embodiments for clarity, the invention can also be implemented in a single embodiment. Certain embodiments of the invention can include features from different embodiments disclosed above, and certain embodiments can incorporate elements from other embodiments disclosed above. The disclosure of elements of the invention in the context of a specific embodiment is not to be taken as limiting their use in the specific embodiment alone. Furthermore, it is to be understood that the invention can be carried out or practiced in various ways and that the invention can be implemented in certain embodiments other than the ones outlined in the description above. 
     The invention is not limited to those diagrams or to the corresponding descriptions. For example, flow need not move through each illustrated box or state, or in exactly the same order as illustrated and described. Meanings of technical and scientific terms used herein are to be commonly understood as by one of ordinary skill in the art to which the invention belongs, unless otherwise defined. While the invention has been described with respect to a limited number of embodiments, these should not be construed as limitations on the scope of the invention, but rather as exemplifications of some of the preferred embodiments. Other possible variations, modifications, and applications are also within the scope of the invention. Accordingly, the scope of the invention should not be limited by what has thus far been described, but by the appended claims and their legal equivalents.