Abstract:
Enhanced vehicle handling is achieved by the improved suspension systems constructed in accordance with aspects of the present invention, in which not only do the roll couple and jacking couple oppose each other, thereby causing the body roll to counteract the jacking effect, but also the pitch couple and the pitching couple oppose each other, thereby causing the body pitch to counteract the pitching effect. This results in the improvement of the cornering traction of the vehicle, the braking traction of the vehicle, the acceleration traction of the vehicle (especially in a front-wheel-drive vehicle), the simultaneous cornering and braking traction of the vehicle, and the simultaneous cornering and acceleration traction of the vehicle.

Description:
CROSS-REFERENCES TO RELATED APPLICATIONS 
       [0001]    This application is a continuation of application Ser. No. 12/127,761, filed May 27, 2008, which is a continuation of application Ser. No. 10/667,105, filed Sep. 18, 2003, now U.S. Pat. No. 7,377,522, which claims the benefit of Provisional Application No. 60/412,045, filed Sep. 18, 2002, the disclosures of which are hereby incorporated by reference. 
     
    
     BACKGROUND 
       [0002]    When negotiating a curve with a typical automotive-type vehicle, the resulting centrifugal forces tend to roll the vehicle body and associated chassis (hereinafter jointly referred to as “body”) about its roll center relative to the underlying suspension system, and also displace the body and suspension system laterally outwardly relative to the radial center of the curve, tending to cause the vehicle to pivot about its outer wheels. This latter tendency is commonly known in the motor vehicle art as the “jacking effect.” During braking and acceleration, the resulting longitudinal forces acting on a typical automotive-type vehicle tend to pitch the body about its pitch center relative to the underlying suspension system and also tend to displace the body and suspension system forwardly during braking and rearwardly during acceleration to cause the vehicle to pivot about its front or rear wheels, respectively. This is known as the “pitching effect.” 
         [0003]    The locations of the roll center and pitch center are functions of the construction of the vehicle body and the configuration of the vehicle suspension system. In a conventional vehicle, the center of gravity of the vehicle is located above the roll center and pitch center. Since the centrifugal forces caused by cornering and the longitudinal forces caused by accelerating and braking act through the center of gravity of the vehicle, the magnitude of the couple tending to cause the body to roll about its roll center is a function of the magnitude of the centrifugal force and the vertical distance separating the center of gravity from the roll center, and the magnitude of the couple tending to cause the body to pitch about its pitch center is a function of the magnitude of the longitudinal force and the vertical distance separating the center of gravity from the pitch center. These vertical distances are commonly known as the “roll couple” and “pitch couple,” respectively. 
         [0004]    In a typical vehicle, as the body rolls outwardly about its roll center, it tends to compress the outer suspension springs (relative to the radial center of the curve about which the vehicle is traveling) thus increasing the weight on the outer wheels while simultaneously unloading the inward suspension springs, thereby reducing the weight on the inside wheels. As a result, the cornering traction of the vehicle is reduced. Also, as the body pitches forwardly about its pitch center during braking, it tends to compress the forward springs, thus increasing the weight on the forward wheels while simultaneously unloading the rearward springs, thereby reducing the weight on the rearward wheels. This resulting imbalance in the weight being carried by the forward and rearward wheels decreases the maximum braking capacity of the vehicle. The foregoing loading changes on the vehicle wheels caused by cornering and braking will occur simultaneously when the vehicle&#39;s brakes are applied while cornering, thereby potentially causing even greater imbalance on the weights on the vehicle wheels than caused by cornering alone or braking alone. This imbalance may result in the loss of substantially all of the traction of one or more wheels. 
         [0005]    The lateral force tending to cause a vehicle to pivot about its outer wheels, i.e., jacking effect, acts through the portion of the vehicle known as the roll reaction center. The longitudinal forces tending to cause a vehicle to pitch about its forward or rearward wheels acts through the pitch reaction center. In a conventional vehicle, the roll reaction center coincides with the roll center and the pitch reaction center coincides with the pitch center. As a result, the magnitude of the jacking effect is a function of the magnitude of the centrifugal force and the elevation of the roll reaction center above the ground, and the magnitude of the pitching effect is a function of the magnitude of the longitudinal braking/acceleration force and the elevation of the pitch reaction center above the ground. With respect to the effect of cornering forces on a vehicle, the height of the roll reaction center above the ground is commonly known as the jacking couple, and with respect to the effect of braking and acceleration forces on the vehicle, the height of the pitch reaction center above the ground is commonly known as the pitching couple. 
         [0006]    In conventional vehicles, attempts have been made to design the suspension system to minimize the heights of the roll reaction center and pitch reaction center, thereby to reduce the jacking effect and pitching effect. Placement of the roll reaction center and the pitch reaction center at a low elevation, however, results in the center of gravity of the body being located at a substantial distance above the roll center and pitch center, thereby increasing the magnitude of the roll couple and pitch couple. The increase in the roll couple and pitch couple results in decreased stability of the vehicle, especially since in typical suspension systems the body roll and jacking effect and the body pitch and pitching effect are all cumulative, reducing the braking, acceleration and cornering ability of the vehicle. 
         [0007]    Conventional vehicles also do not have any significant accommodation for absorbing the energy of a vehicle crash so as to reduce the likelihood of injury to passengers. As a consequence, all too often passengers are seriously injured, or even killed, during vehicle collisions, some of which do not occur at very high speeds. 
       SUMMARY 
       [0008]    This summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This summary is not intended to identify key features of the claimed subject matter, nor is it intended to be used as an aid in determining the scope of the claimed subject matter. 
         [0009]    Embodiments of the present invention seek to reduce the detrimental effects on vehicle handling caused by braking, by acceleration, by simultaneous cornering and braking, and by simultaneous cornering and acceleration. Embodiments of the present invention constitute an improvement of the vehicle suspension system disclosed in applicant&#39;s prior U.S. Pat. No. 4,550,926 which simply concerns suspension systems for counteracting cornering forces imposed on vehicles. Enhanced vehicle handling is achieved by the improved suspension systems of the present invention, in which not only do the roll couple and jacking couple oppose each other, thereby causing the body roll to counteract the jacking effect, but also the pitch couple and the pitching couple oppose each other, thereby causing the body pitch to counteract the pitching effect, thus improving the cornering traction of the vehicle, the braking traction of the vehicle, the acceleration traction of the vehicle (especially in a front-wheel-drive-vehicle), the simultaneous cornering and braking traction of the vehicle, and the simultaneous cornering and acceleration traction of the vehicle. 
         [0010]    To this end, vehicle suspension systems of the present invention may be joined to the vehicle body to pivot about transverse and/or longitudinal axes located above the center of gravity of the vehicle body so that the cornering forces acting through the center of gravity tilt the body about the longitudinal axis inwardly into the curve and so that simultaneously the longitudinal braking or acceleration forces acting through the center of gravity tilt the body about the transverse axis toward the rear or front, respectively, of the vehicle. 
     
    
     
       DESCRIPTION OF THE DRAWINGS 
         [0011]    The foregoing aspects and many of the attendant advantages of this invention will become more readily appreciated as the same become better understood by reference to the following detailed description, when taken in conjunction with the accompanying drawings, wherein: 
           [0012]      FIG. 1  is a side elevational view of an embodiment of the present invention; 
           [0013]      FIG. 2  is a top view of  FIG. 1  with portions broken away; 
           [0014]      FIG. 3  is an enlarged fragmentary view of the portion of the suspension system of the embodiment of  FIGS. 1 and 2 ; 
           [0015]      FIG. 4  is a side elevational view of another embodiment of the present invention; 
           [0016]      FIG. 5  is a top view of  FIG. 4  with portions broken away; 
           [0017]      FIG. 6  is a top view of a further embodiment of the present invention; 
           [0018]      FIG. 7  is a side elevational view of  FIG. 6 ; 
           [0019]      FIG. 8  is a front elevational view of  FIGS. 6 and 7 ; 
           [0020]      FIG. 9  is a further front elevational view of the embodiment shown in  FIGS. 6 ,  7  and  8  with the body and tie structure tilted as when negotiating a curve; 
           [0021]      FIG. 10  is a top view of a further embodiment of the present invention; 
           [0022]      FIG. 11  is a side elevational view of  FIG. 10 ; 
           [0023]      FIG. 12  is an enlarged fragmentary view of portions of the embodiment shown in  FIGS. 10 and 11 ; 
           [0024]      FIG. 13  is a further embodiment of the present invention in side elevational view; 
           [0025]      FIGS. 14 ,  15  and  16  illustrate a further embodiment of the present invention in front elevational, side elevational and top view; 
           [0026]      FIG. 17  is a front view of a further embodiment of the present invention; 
           [0027]      FIG. 18  is a front view of another embodiment of the present invention; 
           [0028]      FIG. 19  is an enlarged fragmentary view of a portion of  FIG. 18 ; 
           [0029]      FIG. 20  is a front elevational view of a further embodiment of the present invention; 
           [0030]      FIGS. 21 and 22  are top cross-sectional views of  FIG. 20 ; 
           [0031]      FIG. 23  is an enlarged, fragmentary, elevational view of  FIG. 20 ; 
           [0032]      FIGS. 24 ,  25  and  26  illustrate a further embodiment of the present inventions in front elevational view, top view and fragmentary side elevation view; 
           [0033]      FIG. 27  is a front elevational view of a further embodiment of the present invention; 
           [0034]      FIG. 28  is another front elevational view of a further embodiment of the present invention; 
           [0035]      FIG. 29  is a side elevational view of a further embodiment of the present invention; 
           [0036]      FIG. 30  is a top view of another embodiment of the present invention; 
           [0037]      FIG. 31  is a side elevational view of  FIG. 30 ; 
           [0038]      FIG. 32  is a partial front elevational view of a further embodiment to the present invention; 
           [0039]      FIG. 33  is a top elevational view of a portion of  FIG. 32 ; 
           [0040]      FIG. 34  is a fragmentary front elevational view of a further embodiment of the present invention; 
           [0041]      FIG. 35  is a fragmentary front elevational view of a further embodiment of the present invention; 
           [0042]      FIG. 36  is a side elevational view of  FIG. 35 ; 
           [0043]      FIG. 37  is a fragmentary top view showing a further embodiment of the present invention; 
           [0044]      FIG. 38  is a further alternative of the embodiment of the present invention shown in  FIG. 37 ; 
           [0045]      FIG. 39  is a front elevational view of a further embodiment of the present invention; 
           [0046]      FIG. 40  is a front elevational view of a further embodiment of the present invention; 
           [0047]      FIG. 41  is a front elevational view of a further embodiment of the present invention; 
           [0048]      FIG. 42  is a side elevational view of a further embodiment of the present invention; 
           [0049]      FIG. 43  is an enlarged fragmentary view of  FIG. 42 ; 
           [0050]      FIG. 44  is a side elevational view of a further embodiment of the present invention; 
           [0051]      FIG. 45  is a side elevational view of another embodiment of the present invention; 
           [0052]      FIG. 46  is a cross-sectional view of  FIG. 45  taken substantially along lines  46 - 46  thereof; 
           [0053]      FIG. 47  is an enlarged fragmentary view of  FIG. 45 ; 
           [0054]      FIG. 48  is a side elevational view of a further embodiment of the present invention; 
           [0055]      FIG. 49  is a side elevational view of a further embodiment of the present invention; 
           [0056]      FIG. 50  is a front elevational view of the present invention integrated into a railway car; 
           [0057]      FIG. 51  is a top elevational view of  FIG. 50 ; 
           [0058]      FIG. 52  is a view similar to  FIG. 50  of another embodiment of the present invention; 
           [0059]      FIG. 53  is a partial front view of a further embodiment of the present invention; 
           [0060]      FIG. 54  is another partial front view of a further embodiment of the present invention; 
           [0061]      FIG. 55  is a partial top view of another embodiment of the present invention; 
           [0062]      FIG. 56  is a fragmentary top elevational view of  FIG. 55 ; 
           [0063]      FIG. 57  is a fragmentary front view of a further embodiment of the present invention; and 
           [0064]      FIG. 58  is a fragmentary side view of  FIG. 57 . 
       
    
    
     DETAILED DESCRIPTION 
       [0065]    Referring initially to  FIGS. 1 and 2 , a vehicle  50  having a body  52  is shown as mounted on the suspension system  54  of the present invention, which in turn is supported on forward wheel assemblies  56  and rearward wheel assemblies  58 . An elongated tie structure  60  is interposed between the vehicle body  52  and the wheel assemblies  56  and  58 . The tie structure  60  may extend longitudinally along the lower elevation of the vehicle  50  and is interconnected to the body  52  through a slide assembly  62  to enable the body to slide longitudinally relative to the tie structure as well as pivot about a longitudinal axis  64  which is located at an elevation above the center of gravity  66  of the vehicle  50 . The tie structure  60  is also connected to the wheels  56  and  58  by pivot arm assembles  68 . 
         [0066]    As used in the present application, the term “body” is intended to include a relatively rigid structure that may include a chassis, frame and/or the body thereof, and any additional supports and members attached thereto for accommodating the suspension system of the present invention. 
         [0067]    The body  52  has a forward portion  52 F and a rearward portion  52 R. The body  52  may be constructed with a conventional body shell and an underlying chassis, may be in the form of a unibody having an integral chassis, or may be constructed in other manners without departing from the spirit or scope of the present invention. 
         [0068]    At the front of the vehicle  50 , as shown in  FIG. 1 , the suspension system  54  includes load support and control devices in the form of combination spring/shock absorber assemblies  70  for supporting the vehicle body  52 . The upper ends of the spring/shock absorber assemblies  70  are coupled to a body structure member  72  utilizing a ball joint connection  74 . The lower ends of the spring/shock absorber assemblies  70  are interconnected to forward hub carriers  76  of the wheel assemblies  56 . The forward hub carriers are connected to the forward end portions of the tie structure  60  by pivot arm assemblies  68  through ball joints  78  located at the distal ends of the pivot arm assemblies. Spring/shock absorber assemblies, such as assemblies  70 , are well known in the art and are commonly referred to as MacPherson struts. MacPherson struts are widely used in conjunction with both front-wheel and rear-wheel drive vehicles. 
         [0069]    Referring to  FIG. 3 , at the forward corners the tie structure  60  is connected to the hub carriers  76  by the pivot arm assemblies  68 . Each pivot arm assembly includes a generally triangular-shaped pivot arm  68 A composed of a longitudinal member  68 B, a transverse member  68 C 1 , and a diagonal member  68 C, which cooperatively form the triangular shape. The pivot arm may be adapted to pivot relative to the forward end of tie structure  60  about a transverse axis. To this end, the end of each pivot arm longitudinal member  68 B extends beyond the transverse member  68 C 1  to be closely receivable between a pair of mounting ears  68 D extending longitudinally from the forward end of the tie structure  60 . A pivot pin  68 E extends through the center of a bushing  68 F pressed within a bore formed in the end of the longitudinal member  68 B, as well as through close-fitting through-bores formed in the mounting ears  68 D. A nut  68 G or other appropriate type of fastener may be engaged with the pin  68 E to retain the pivot arm  68 A between the two mounting ears  68 D. 
         [0070]    A cylindrical stub shaft  68 H extends transversely from an extension  68 I of the pivot arm diagonal member  68 C that extends beyond the transverse member  68 C 1  in the same manner in which the longitudinal member  68 B of the pivot arm extends beyond the transverse member  68 C 1 . The stub shaft  68 H may engage within a close-fitting bushing  68 J pressed within a bore formed in a mounting bracket  68 K, which is secured to the adjacent face of the tie structure end member. The mounting bracket  68 K, which may be composed of a standard, commercially available pillow block, is mounted on the tie structure member by any appropriate means, such as by hardware members  68 L, extending through openings formed in the flange portions of the mounting bracket and into engagement with the end of the tie structure. It will be appreciated that, by this construction, the pivot arm  68 A is adapted to freely pivot about its transverse axis. 
         [0071]    Each pivot arm assembly  68  also includes a spring-type directional control device in the form of a torsion bar  68 M having a splined end  68 N for anti-rotational engagement with the correspondingly splined interior of a stub shaft  68 H. The opposite end of the torsion bar extends through the close-fitting bushing  68 O pressed within a mounting bracket  68 P. The mounting bracket  68 P is secured to the adjacent face of the tie structure  60  by any appropriate method, for instance, by hardware members  68 Q extending through holes formed in the flange portions of the mounting bracket  68 P to threadably engage the tie structure. As with mounting bracket  68 K, the mounting bracket  68 P may be composed of a standard, commercially available pillow block. 
         [0072]    The torsion bar  68 M may be adjusted to impose no appreciable load when the vehicle is at rest and in a level orientation. This is accomplished by adjusting the position of a bearing plate  68 R relative to the free end of a cantilevered swing arm  68 S extending upwardly from the end of the torsion bar  68 M, which extends beyond the mounting bracket  68 P. The lower end of the swing arm  68 S is fixedly attached to the torsion bar  68 M by any appropriate method, for instance, by use of splines (not shown) or weldments (not shown). The bearing plate  68 R is carried by the lead end of a lead screw  68 T, or similar member, extending forwardly from the tie structure  60 . It will be appreciated that the location of the bearing plate is adjusted by rotation of the lead screw  68 T. 
         [0073]    As in any motor vehicle, the forward wheels  56  of vehicle  50  are steerable. Such steering may be carried out by any number of conventional steering systems which may include typical steering arms (not shown) extending from the forward hub carriers  76  to interconnect with a transfer steering rod assembly (not shown). The steering rod assembly may extend outwardly from a rack and pinion assembly (not shown) mounted on the tie structure  60 . Typically, the interconnection between the steering rod assemblies and the rack and pinion assembly permits the steering rod to pivot in response to the up-and-down and other movement to the front wheels relative to the tie structure. Typically, this is made possible by utilizing ball joints between the steering rod assemblies and the hub carriers, as well as between the steering rod assemblies and the rack and pinion assembly. 
         [0074]    At the rear of the vehicle  50 , the suspension system  54  includes load supporting and control devices in the form of combination spring/shock absorber assemblies  80  for supporting a rear portion  52 R of the vehicle body. The rear spring/shock absorber assemblies  80  may be similar in construction and installation to the forward spring/shock absorber assemblies  70 . In this regard, the upper ends of the rear spring/shock absorber assemblies  80  are secured to overhead portions of the body  52  at rear locations of the body structure member  72  through the use of ball joints  82 . The lower ends of the spring/shock absorber assemblies  80  are coupled to and carried by rear hub carriers  84  of the rear wheel assemblies  58 . 
         [0075]    The rear hub carriers  84  are connected to the distal, rearward ends of pivot arm assemblies  86  by ball joints  82 . The pivot arm assemblies  86  may be similar in construction and operation to pivot arm assembly  68 , described above. The rear wheels  58  may be powered by vehicle engine  89  mounted on the tie structure. Alternatively, the engine and associated drive train may be mounted on the body instead of the tie structure. In a manner typical of conventional vehicles, a transmission  90  may be interposed between engine  88  and a rearwardly extending drive shaft  92 . The rearward end of the drive shaft is coupled to a differential  94 . Transverse axial shafts  96  extend outwardly from opposite sides of the differential  94  to drive the rear wheel assemblies  58 . 
         [0076]    Optionally, a dampening system may be used in conjunction with the rear pivot arm assemblies  86 , as well as the front pivot arm assemblies  68 . In this regard, a dampening system  95  is shown in  FIG. 1  in conjunction with rear pivot arm assembly  86 . The dampening system  95  includes a bracket  97  fixed to and extending laterally from pivot arm of the pivot arm assembly  86  to be coupled to the distal end of a dampener/shock absorber  99 , which in turn is coupled to a bracket  101  depending downwardly from tie structure longitudinal side member  98 . It will be appreciated that by this construction the pivoting movement of the pivot arm assembly is dampened to a degree desired. 
         [0077]    As shown in  FIGS. 1 and 2 , the tie structure  60  of the present invention may be generally in the form of a rectangular box type structure that extends longitudinally along the lower elevations of vehicle  50  between the hub carriers of the forward and rearward wheels  56  and  58 . In one embodiment of the present invention the tie structure may be composed of elongated top and bottom side members  98  and  100  extending along both sides of the vehicle  50  and spaced vertically apart by forward and rearward vertical members  102  and  104 , as well as by forward and rearward intermediate vertical members  106 . The forward ends of the longitudinal members  98  and  100  may be transversely connected by upper and lower crossmembers  108  and  110 . These same crossmembers may be utilized at the rear end of the tie structure  60 . A plurality of intermediate crossmembers  112  may be utilized for reinforcing purposes. Additional reinforcing members (not shown) may be added to the tie structure  60 , if needed. The tie structure  60  may be constructed from many appropriate materials, such as tubing or channel stock. Moreover, the tie structure may be constructed in other configurations without departing from the spirit or scope of the present invention. 
         [0078]    The slide system  62  extends longitudinally between body  52  and tie structure  60 , and is supported above the tie structure by forward and rearward assemblies  114  and  116  that may be in the form of A-arms or other structure. As shown in  FIGS. 1 and 2 , the arm assembly  114  includes opposed arm Sections  118  and  120  interconnected with crossarms  121 A and  121 B to form a rigid assembly structure. The forward end portion of arm Sections  118  and  120  are pivotally pinned at the lower forward ends to the corner portions of the upper section of the tie structure  60 . A cross pin  122  captures the forward lower end portion of the arm Sections  118  and  120  between parallel, spaced-apart mounting ears  124  and  126  extending upwardly from the tie structure  60 . From the connection location with the tie structure  60 , the arm Sections  118  and  120  extend upwardly and inwardly to couple with a gimbal assembly  128  mounted on the forward end of a stub shaft  130  projecting forwardly from slide  132  of the slide assembly  62 . A cross shaft  134  connects the adjacent ends of arm Sections  118  and  120  to the gimbal assembly  128 . In this manner, the slide  132  together with the body is capable of tilting about longitudinal axis  64  (defined by stub shaft  130  and gimbal  128 ) relative to arm assembly  114 . In addition, the slide  132 , together with the body, is capable of pitching movement relative to the arm assembly  114  at an axis  135  extending transversely through the gimbal assembly  128  to pitch about a pitch center PC defined by the intersection of lines  135 A and  135 B extending from arm assemblies  114  and  116  as shown in  FIG. 1 . 
         [0079]    The rear arm assemblies  116  may be constructed similarly to the forward arm assemblies  114 . Thus, the construction of the rearward arm assembly  116  will not be repeated here. Also, it is to be understood that rather than using front and rear arm assemblies, the slide system would be supported by arm assemblies that are coupled to side portions of the tie structure  60 . 
         [0080]    The slide assembly  62  includes an elongate, rectangular, slide member  132  extending through and capable of sliding relative to an exterior longitudinal collar-type slideway  136  that may encase the entire, or at least a portion of, the slide  132  extending between the forward arm  114  and rearward arm assemblies  116 . The slideway  136  may be attached to vehicle body  52  by attachment brackets  138  or by other convenient technique. 
         [0081]    As will be appreciated, the slide system  62  enables the body  52  to move longitudinally relative to the tie structure  60 . For example, if the body  52  impacts against another vehicle or other structure, this relative movement between the body and tie structure enables the body to move relative to the tie structure in the direction that the impact load is applied to the body, i.e., away from the impact location. This may advantageously result in reduced crash forces imposed on passengers in the vehicle (especially if the vehicle seat or seats are adapted to move relative to the body  52 , in a manner for example, disclosed below) and less damage to the vehicle since some of the energy of the impact is expended in moving the slide  132  relative to the slideway  136 . 
         [0082]    The slideway may be nominally held in position relative to the slide  132  by a shear pin  139 . If a crash occurs, as described above, the shear pin  139  will break, allowing relative movement of the body  52  and tie structure  60 . In addition, a selected friction load may be applied between the slide  132  and the slideway  136  to help absorb the force applied to the vehicle during a crash. Moreover, such friction load can be designed to increase linearly or nonlinearly with the distance of relative travel between the slide  132  and the slideway  136 . Also, other techniques may be used to nominally position the slideway  136  relative to the slide, such as through the use of springs or other resilient members (not shown). 
         [0083]    It is to be understood that vehicle  50  may be constructed without the slide system  62  and still provide significant advantages over conventional automobiles and other vehicles. 
         [0084]    It will be appreciated that in the embodiment of the present invention shown in  FIGS. 1 and 2 , as well as in other embodiments of the present invention, if the body moves significantly due to a crash or other large impact load, the connections between the spring/shock absorber assemblies  70  and  80  with the body and/or hub carriers are designed to break away. Such break away connection can be designed to not cause significant damage to the spring/shock absorber assemblies, so that they can be re-used. 
         [0085]    Also, it will be appreciated that portions of the body may be constructed with crushable body panels or parts that absorb at least some of the energy during a crash. This could result in less overall damage to the vehicle and less injury to the passengers, as opposed to a conventional vehicle. 
         [0086]    In another aspect of the present invention, when the vehicle  50  is cornering, the centrifugal force imposed on the body  52  acts at the center of gravity  66 , which is below the elevation of gimbals  128 , resulting in the outward lateral movement of the center of gravity, thereby causing the body to tilt about the longitudinal axis  64  or roll center at the gimbals  128 , rather than imposing a jacking effect on the vehicle. As a result, the body  52  is tilted inwardly about axis  64  in the direction towards the center of the curve along which the vehicle  50  is traveling. The body, as thus tilted, thereby compresses the inside springs  70  and  80  and causes extension of the outside springs. In addition, by the inward tilting of the body, a relatively larger load is retained on the inside wheel assemblies of the vehicle  50 , rather than being shifted substantially to the outside wheel assemblies of the vehicle in the manner of a conventional vehicle. This enables vehicle  50  to maintain better traction when negotiating a corner than a conventional vehicle. 
         [0087]    In addition, when the vehicle  50  negotiates a corner, the centrifugal forces acting on the body  52  and the tie structure  60  cause the outward pivot arm assemblies  68  and  86  to pivot about the tie structure to wind up the torsion bars  68 M, thereby to allow the outward side of the tie structure to lower somewhat. Simultaneously, the centrifugal forces acting on the body  52  and the tie structure  60  tend to cause the inward pivot arm assemblies to pivot in the opposite direction about the tie structure, thereby allowing the inward side of the tie structure to raise upwardly somewhat relative to the body. This outward roll of the tie structure is significantly less than the inward roll of the body noted above. 
         [0088]    During the rolling movement of the tie structure, the rate of force transfer through the tie structure is reduced since it acts over an extended period of time rather than substantially instantaneously. As a consequence, the jacking effect imposed on the vehicle  50  is reduced. The jacking effect is what tends to raise the inside wheels and roll the vehicle about its outside wheels during cornering. As a result, the effective roll reaction center of the vehicle is at an elevation below the elevation of the pivot axis  64 . The roll reaction center is the elevation point through which the lateral forces act to cause the jacking effect. 
         [0089]    The combination spring/shock absorbers  70  and  80 , and optionally the torsion bars  68 M, may be sized so that the roll stiffness of the tie structure is higher than the roll stiffness of the body. Thus, the amount by which the tie structure rolls outwardly during cornering is significantly less than the amount by which the body at the same time tilts inwardly, so that the net effect is to maintain the body in an inwardly tilted orientation relative to the tie structure, even though the tie structure is rolling somewhat in the outward direction, as described above. Also, the body  52  is permitted to move relatively further than the tie structure  60 , but the body movement stops relative to the tie structure before the tie structure movement stops. 
         [0090]    Still referring to  FIGS. 1 and 2 , stop or limit members  140  may be imposed between the arms  118  and  120  and the tie structure  60  to limit the angular movement of the arms, at least in the direction toward the tie structure. Such stops  140  may be composed of resilient blocks mounted to the underside of the A-arms to press against the adjacent portion of the tie structure when the A-arm pivots about its connection to the tie structure towards the tie structure. The resilient block may be configured to impose a progressively higher rate of resistance with increased deformation of the blocks, thereby providing a rising rate of resistance materials for blocks exhibiting these characteristics, including natural or synthetic rubber. Of course, numerous other systems could be utilized to limit the tilt or movement of the A-arms toward (and also away from) the tie structure, as desired. 
         [0091]    In addition to, or in lieu of, stops  140  between arms  118  and  120  and the tie structure  60 , stops may also be employed to limit the amount of roll or pitch of the body relative to the tie structure. In this regard, roll and/or pitch stops  142  may be mounted on the upper end of posts or similar structures  144  extending upwardly from the forward and rearward ends of the tie structure. It is believed desirable to incorporate the body stops  142  so that the roll of the body terminates before the roll of the tie structure terminates during cornering. It is desirable to allow the shifting of the tie structure to occur over a time period longer than it takes for the body roll or pitch to be completed, thereby to reduce, to the extent possible, the rate of centrifugal force transfer between the body and tie structure, since during this shifting movement the full jacking effect caused by the centrifugal force imposed on the vehicle during cornering is not brought to bear on the vehicle. 
         [0092]    It will also be appreciated that the present invention advantageously helps keep the body relatively level when a wheel hits a hole or depression or hits a bump in the road. For example, if a front wheel  56  hits a pothole, the corresponding portion of the tie structure lowers. Since the roll center is above the center of gravity, the body will swing up about the roll center at the location that the tie structure lowers. As such, the body tends to stay relatively level, even when the wheel and associated portion of the tie structure drop due to the pothole. It will be appreciated that if the wheel assembly hits a bump, the tie structure will raise and the body will tend to lower relative to the raised portion of the tie structure, thereby tending to keep the body relatively level. 
         [0093]    Although the interconnections between the ends of the slide system  62  and the tie structure  60  are illustrated in  FIGS. 1 and 2  as accomplished through the use of forward and rearward arm assemblies  114  and  116 , the arm assemblies may be replaced with alternative structures. For example, the arms  118  and  120  may extend parallel to each other, in which case the transverse shaft  134  of the gimbal  128  may be lengthened to accommodate this different configuration of the arms. 
         [0094]    Although the vehicle  50  has been described and illustrated as accommodating longitudinal movement between the body  52  and the tie structure  60 , the body may also be adapted to shift sideways relative to the tie structure. In this regard, the attachment brackets  138  used to attach the body to the slide assembly may be replaced with a transverse slide assembly permitting transverse movement of the body relative to the tie structure. Such transverse slide assembly can be of many constructions, including rods that slide within collars, slides that slide within a slideway, etc. 
         [0095]    Although the vehicle  50  has been described above as employing an engine  89  that drives the rear wheels  58 , in addition, or as an alternative, electric motors may be incorporated within the wheel assemblies  56  and/or  58  to provide motive force to the vehicle. The electric motors may be of many constructions, for example as shown and described in U.S. Pat. No. 5,438,228, which is incorporated herein by reference. It is to be understood that other electric motor configurations may be utilized without departing from the spirit or scope of the present invention. 
         [0096]    Body  52  may be detachably mounted to the tie structure  60 . In this regard, fasteners or connectors, such as threaded connectors  146 , may be used to secure body structural member  72  to the slide assembly brackets  138 . Detachably attaching the body to the tie structure results in numerous advantages. For instance, if the body is damaged, it can be easily removed and replaced. In addition, multiple body configurations could be utilized with a particular tie structure and chassis. Thus, the vehicle owner can convert the vehicle into different uses or for example as a passenger vehicle, enclosed load carrying vehicle, or an open box load carrying vehicle, perhaps similar to a pickup truck. To accommodate a detachable body, electrical connections can be incorporated between the body and the tie structure that automatically connect the electrical lines when the body is mounted on the tie structure and correspondingly automatically disconnect the electrical lines when the body is detached from the tie structure. In addition, the steering of the vehicle can be accomplished through electrical servo motors, linear actuators, etc., rather than through mechanical linkages. In this manner it will not be necessary to separately connect and disconnect steering linkages that may extend between the body and the tie structure, the vehicle frame or the hub carrier. Also, if servo motors, etc., are used, a conventional steering wheel can be replaced with a “steering stick,” perhaps similar to the control stick of aircraft. 
         [0097]    Another embodiment of the present invention is illustrated in  FIGS. 4 and 5 . In this embodiment, vehicle  150  was constructed similarly to vehicle  50  of  FIGS. 1 ,  2  and  3 , but with the exception of a slide system  152 . Thus, like parts in  FIGS. 3 and 4  are numbered the same as in  FIGS. 1 ,  2 , and  3 , but with the addition of the suffix “A.” 
         [0098]    The slide system  152  may be constructed with a cross-shaped slide collar housing  154  for receiving therein four separate slides  156 ,  158 ,  160  and  162  extending from the slide housing  154  in the forward, right hand, rearward and left hand directions, respectively, relative to the direction of the vehicle  150 . The outward ends of the slides  156  and  160  may be attached to brackets  164  and  166 , respectively, extending upwardly from transverse intermediate crossmembers  112 A of the tie structure  60 A. The outward ends of the lateral slides  158  and  162  may be attached to brackets  168  extending downwardly from body structural member  72 A. A compressible member  170  may be positioned between the inward ends of each of the slides  156 ,  158 ,  160  and  162  and a stop  171  disposed inwardly of the adjacent end of the slides. The compression member  170  may place a nominally outward load on the slides, which load can be overcome if a sufficiently high relative force is imposed between the vehicle body  52 A and the tie structure  60 A. The compressible member  170  can be composed of various structures, such as a compression spring, crushable material, etc. Perhaps one advantage of the use of a compression spring as the compressible member is that after relative movement takes place between the body  52 A and the tie structure  60 A, the body can be returned to a nominal position relative to the tie structure. 
         [0099]    It will be appreciated that the body  52 A is capable of moving both longitudinally and laterally relative to the tie structure  60 A, thereby to accommodate loads imposed on the body in both the longitudinal and transverse directions. Moreover, with the present invention, the body is capable of tilting relative to the tie structure  604  about longitudinal axis  64 A extending concentrically relative to slides  156  and  160 . Also, the body is capable of pitching relative to the tie structure  60 A about the transverse axis  172  extending concentrically with the transverse slides  158  and  162 . 
         [0100]    It will be appreciated that during normal operation of vehicle  150 , the slide system may be designed to not come into play. The vehicle body is able to roll about longitudinal axis  64 A, and pitch about transverse axis  172  without the body moving relative to the tie structure  60 A through the slide system  152 . In other words, the roll and pitch stiffness of the body due to springs  70 A and  80 A is less than lateral and/or longitudinal displacement stiffness of the body due to compression members  170 . 
         [0101]    Alternatively, the slide assembly  152  may be designed to function during the normal operation of the vehicle. For example, the slide assembly  152  may be designed to shift longitudinally or laterally during the normal operation of the vehicle. 
         [0102]    Rather than it being “passive,” the slide system  152  may be powered to actively shift the body  52 A relative to the tie structure  60 A. In this regard, compressible member  170  of the slide system  152  may be replaced by fluid, for instance, hydraulic fluid, that may be delivered to and extracted from selected locations in the housing  154  by a fluid pump  173  in fluid flow communication with the housing  154  by lines  174 A and  174 B. A fluid reservoir  175  may be utilized with the fluid pump to store extra fluid as well as the return fluid from the housing  154 . Although the fluid pump  173  is illustrated as being in fluid flow communication with the housing  154  in the fore and aft directions, the fluid pump  173  can also be used to shift the body  52 A in the lateral direction. 
         [0103]    It will be appreciated that the slide system  152 , as well as other slide systems of the present invention, might be conveniently and advantageously incorporated into a pre-existing vehicle. Of course, some modifications to the vehicle likely would be required so that the slide system  152  can be interposed between the existing vehicle body and existing vehicle chassis/frame. Perhaps it is more likely that adaptation of a slide system  152  into an existing vehicle might be easier to accomplish if the vehicle has a body with a separate underlying frame rather than being of a unibody construction. 
         [0104]    Portions of the body  52 A may be constructed from crushable material to absorb some of the energy from an impact force imposed on the vehicle. Such body portions may be designed to be easily removable from the vehicle to facilitate replacement thereof. It will be appreciated that by a combination of constructing the body  52 A with crushable material and utilizing the slide system  152 , described above, the vehicle can be made to better protect passengers during a crash, and also reduce the overall damage caused to the vehicle. 
         [0105]      FIGS. 6 ,  7  and  8  disclose a further embodiment of the present invention wherein a vehicle  176  is shown as having a body structure  178  positioned within the perimeter of a tie structure  180 . The vehicle is mounted on forward and rearward wheel assemblies  182  and  184 . As in the prior embodiments of the present invention, described above, the body structure  178  is capable of longitudinal and lateral movement relative to the tie structure  180  and is also capable of tilting relative to the tie structure about a longitudinal axis  186 . Also, as discussed more fully below, the body is capable of pitching about a transverse axis  278  relative to the tie structure. 
         [0106]    The tie structure  180  shown in  FIGS. 5 ,  6 , and  7  may be shaped and constructed somewhat similarly to the tie structures  60  and  60 A noted above. In this regard, the tie structure may be in the form of a rectangular box-type structure that extends longitudinally along the lower elevations of the vehicle  176 . The tie structure may be composed of elongated top and bottom side beams  188  and  190  extending along both sides of the vehicle, and spaced vertically apart by forward and rearward vertical members  192  and  194  as well as intermediate vertical members (not shown). The forward ends of the side beams  188  and  190  may be transversely connected by upper and lower crossmembers  196  and  198 . The same types of crossmembers may be utilized at the rear end of the tie structure  180 . One or more intermediate crossmembers (not shown) may be utilized for reinforcing purposes. Such crossmembers may extend through the body  178 . Additional reinforcing members (also not shown) may be added to the tie structure, as needed. Such reinforcing members may also extend through the body. It is to be understood that the tie structure  180  may be constructed from many appropriate materials, such as tubing or channel stock. Moreover, the tie structure may be constructed in other configurations without departing from the spirit or scope of the present invention. 
         [0107]    The tie structure  180  may be supported by wheel assemblies  182  and  184  through the use of torsion assemblies  200 . The inboard ends of the torsion bar assemblies  200  may be connected to the tie structure  180  in a manner similar to that illustrated and described above in relation to  FIGS. 1 ,  2  and  3 . The outboard ends of the torsion bar assemblies  200  may be connected to the lower portions of wheels hub assemblies  201  through the use of ball joint assemblies in a well-known manner. 
         [0108]    The body structure  178  is illustrated in  FIGS. 6-8  as being of a generally tubular or similar construction and positioned partially within the perimeter of the tie structure. The body structure may include a rectangular box-type structure composed of upper and lower side beams  204  and  206  extending along opposite sides of the body and vertically spaced apart by forward and rearward vertical members  208  and  210 . Additional vertical members (not shown) may be utilized intermediate the forward and rearward vertical members. The forward and rearward ends of the longitudinal upper and lower side beams  204  and  206  may be transversely connected by upper and lower crossmembers  212  and  214 . 
         [0109]    The body structure  178  can be covered by a body shell (not shown) in the manner of race cars. Ideally, the body shell is easily removable from the body structure. 
         [0110]    The body structure  178  may be connected to the tie structure  180  through the use of an intermediate slide assembly  216  that spans across an intermediate portion of the tie structure at or near the fore and aft center of the vehicle. The slide assembly  216  may include a transverse central bar member  216 A having blind bores formed in the ends thereof for slidably receiving plunger rods  216 B therein. A compression spring or other resilient device  216 C may be interposed between the blind ends of the bores formed in the bar  216 A and the adjacent, inward ends of the rods  216 B, thereby to impose a nominal outward load on the rods. A pivot pin  217  may extend outwardly from the ends of the rods  216 B to engage within close-fitting through-holes formed in slide plate assemblies  218 , which slidably engage with a slideway  220  positioned along the top of the tie structure upper side beams  188 . The slide plate block  218  may have a bottom transverse slide section that closely engages within and is slideable relative to the slideway  220 . The slide plate assemblies may also include upright plate portions that extend upwardly from transverse slide section to pass through a narrow slot or entrance formed in the upper section of the slideway  220  (at the upper portion of side beams  188 ), to an elevation corresponding to the end portion of slide assembly  216 . It will be appreciated that other alternative constructions for slide plate assemblies  218  and slideway  220  may be utilized without departing from the spirit or scope of the present invention. Also, the slide plate assembly  218  may be nominally positioned relative to the length of slideway  220  by any convenient means, such as by use of compression or extension springs or shear pins (not shown). 
         [0111]    The body structure  178  may be coupled to the immediate slide assembly  216  by use of a bracket  224  that extends downwardly from the central upper portion of the body to be pinned to the intermediate slide assembly by a longitudinal pin  226  that is longitudinally aligned with roll axis  186 . This construction allows the body structure  178  to roll relative to the intermediate slide assembly  216  and tie structure  180  about the roll axis  186 . The body structure  178  is supported and stabilized relative to the hub assemblies  201  by strut assemblies  232  that extend upwardly from the hub assemblies for connection to upper portions of the body by use of standard connection joints, such as ball joints  236 . 
         [0112]    Turning now to  FIGS. 6-8 , there is shown one exemplary embodiment of a system for achieving relative longitudinal movement (lateral movement may also be provided) between the tie structure  180  and the body  178  upon impact loads applied to the tie structure with the distance of relative movement proportional, or otherwise related, to the magnitude of the impact load. This system includes a forward bumper assembly  240  mounted against the forward end of the tie structure  180  by mounting bracket  242 . The forward bumper assembly  240  may include a plurality of telescoping, forwardly extending tubular members  244 A,  244 B,  244 C,  244 D, etc., disposed within an outer, flexible cover structure  246 . The telescoping members  244  may be designed to contract or compress when the bumper assembly  246  impacts against another vehicle or other object in a controlled manner so as to dissipate some of the force of the impact. 
         [0113]    The interior of the bumper  246  may be filled with a fluid that can be used to enhance the structural integrity of the bumper assembly. The fluid within the bumper assembly  240  may also be utilized to shift the body  178  relative to the tie structure  180  when the bumper assembly impacts against another vehicle or other object. To this end, an elongate manifold  248  extends at least partially along the width of the bumper, at the rearward portion thereof. The manifold  248  is in fluid flow communication with the fluid within the bumper assembly  240 . The manifold  248  may be in the form of a tubular member or of other appropriate construction. 
         [0114]    The manifold  248  is in fluid flow communication with fluid actuators  250  which are illustrated in  FIGS. 6-8  as being in the form of a fluid cylinder. The actuators  250  each includes a cylinder portion  252  in fluid flow communication with the bumper assembly  240  through a fluid pipe or a line  254 . The cylinders  252  are pinned to the upper side beams  188  of the tie structure  180  by a pair of parallel, spaced apart mounting ears  256  extending upwardly from the upper surfaces of the beams  188  to receive the adjacent ends of the cylinders  252  therebetween. Close-fitting pins  258  extend through aligned openings formed in the mounting ears  256  and in the adjacent end of the cylinder  252  to pivotally couple cylinders  252  to the mounting ears. A piston rod  260  is extendible outwardly of the opposite end of the cylinder  252 . The forward or free end of the rod  260  is pinned to the forward portion of slide plate  218  for the use of a pivot pin  262 . 
         [0115]    The vehicle  176  also may include a rear bumper assembly  264  that may be constructed essentially identically or at least somewhat similarly to the forward bumper assembly  240 . As with the forward bumper assembly  240 , the rearward bumper assembly  264  may also function as a bladder for fluid used to shift the body structure  178  relative to the tie structure  180  during a crash or application of an input load to the tie structure. To this end, the rear bumper assembly  264  may be in fluid flow communication with rearward fluid actuators  266 , that may be constructed essentially identically or similarly to the forward fluid actuators  250 . As such, the details of the construction of the rear bumper assembly  264  and rear fluid actuators  266  will not be repeated here. 
         [0116]    As an alternative, the fluid actuated system, described above, may be replaced with a mechanical linkage system (not shown). The mechanical linkage system can be configured so that if an impact load is applied to the front and rear bumper assembly  240 ,  264 , the body can be shifted away from the location of the impact relative to the bumper. 
         [0117]    A seat assembly  268  for the vehicle driver/occupant is located in the forward portion of the body  178 . Although the vehicle  176  is illustrated as configured for limited occupancy, for instance for racing, the vehicle may be reconfigured to carry a plurality of passengers. In this regard, the body  178  may be widened relative to the width of the tie structure so as to occupy substantially the entire width between the side beams  188  and  190  of the tie structure. 
         [0118]    The seat assembly may be mounted on a slide system to move under impact in the manner of the seat assemblies shown in  FIG. 13 . Also, the assembly  268  may be enclosed in a surrounding cockpit  269 , which in turn may be mounted on a slide assembly (not shown) to protect the driver and allow the cockpit to continue to move in the direction of travel of the vehicle despite the impact force applied to the vehicle. 
         [0119]    A propulsion engine  270  is illustrated as disposed within the rear portion of the body  178 . The engine  270  may be coupled to a transaxle  272  to transmit the engine power to rear wheel assemblies  184  through drive axles  274  that extend transversely outwardly from each side of the transaxle to drivingly engage the rear wheel assemblies  184  in a manner well known in the art. Universal joints, constant velocity joints or other connectors may be utilized between the transaxle  272  and the drive axles  274  as well as between the drive axles and the rear wheel assemblies  182  in a manner well known in the art to accommodate relative movement between the transaxle and the rear wheel assemblies. Moreover, rather than carrying the weight of the engine  270  in the body  178 , the engine can instead be mounted on the tie structure  180 . 
         [0120]    As a further aspect of the present invention, an air foil/ground effect structure  276  is mounted on the underportion of the body  178 . The air foil or ground effect structure ideally spans between the wheel assemblies  182  and  184  in the side-to-side direction and beyond the wheel assemblies in the fore and aft direction as illustrated in  FIGS. 6-8 . The ground effect structure may be a singular structural member or composed of a plurality of members that cooperatively form the ground effect structure. Also, the ground effect structure may be oriented (tilted downwardly in the forward direction) relative to the ground to cause a partial vacuum to be created under the vehicle, thereby to impart a downward load on the vehicle when traveling at a sufficiently high speed. This downward load on the body is transferred to the tie structure and from there to the forward and rearward wheel assemblies  182  and  184 . 
         [0121]    The ground effect structure  276  may also serve to “close off” the lower front portion of the vehicle  176  to also help create a partial vacuum beneath the vehicle. Also, during use, the pitch of the body may serve to keep the body relatively level with respect to the ground and also maintain a constant distance between the underside of the body and the ground. Also, the ground effect structure  276  may be constructed to be somewhat adjustable in orientation to alter the amount of downward load created, in a manner well known in the art. 
         [0122]    Rather than being carried by the body  178 , the ground effect structure can be connected to the tie structure, so that the downward load created during vehicle travel is imposed on the tie structure rather than on the body. Of course this load is carried through the tie structure connections with the wheel assemblies. Alternatively, a separate air foil  277  may be mounted on the upper portions of the tie structure to impart a downward load thereon. In a known manner, the angle of attack of the air foil may be adjustable so as to vary the downward force generated by the air foil. 
         [0123]    In use, if the vehicle  176  hits or is hit by another vehicle or object at, for instance, the front of the vehicle, the body  178  may shift rearwardly relative to the tie structure  180 , a distance in proportion to the level of impact sustained. In this regard, fluid within the forward bumper assembly  240  may flow out therefrom through lines  254  as the bumper assembly is deformed and thereby reduced in volume. The fluid flowing from the bumper assembly through lines  254  is routed to linear actuators  250 , thereby to extend the piston rods  260  thereof outwardly therefrom, which in turn pushes the slide plates  218  rearwardly relative to the tie structure, thereby shifting the body  178  also rearwardly. Flow restrictors may be used in line  254  or in cylinder  252  to control the rate of movement of the body relative to the tie structure. Also, at the same time, the fluid in the rear actuators flows out of the actuators and into the rear bumper assembly or to a separate actuator (not shown). Further, a flow controller can be incorporated into the rear actuators or rear fluid lines to control the flow of fluid between the rear actuators and the associated accumulator or rear bumper  264 . 
         [0124]    Simultaneously, during breaking, the body may pivot about transverse axis  278  defined by pins  217  due to the braking force being applied to the body at its center of gravity  280 , which is at a level below transverse axis  278 . As such, a larger downward force is applied to the rear springs of the vehicle  176  than in a conventional vehicle (whereupon braking, the pitching of the vehicle imposes a larger downward force on the front vehicle springs and may substantially unload the rear vehicle springs), thereby providing good contact between the rear wheel assemblies  184  and the ground to improve the braking ability of the vehicle. 
         [0125]    In addition, the vehicle  176  is capable of tilting in the inward direction when cornering to compress the inside springs, while at the same time the tie structure  180  is capable of swinging slightly outwardly when cornering, thereby preventing the longitudinal axis  186  of the vehicle from serving as a roll reaction center, i.e., the elevation or point to which the lateral forces act to cause a jacking effect that tends to raise the inside wheels and roll the vehicle about its outside wheels. As a result, as discussed above, the effective roll reaction center of the vehicle is at an elevation below the elevation of the pivot axis  186 , resulting in a lower rate of force transfer being imposed on a vehicle during cornering. Thus, the construction of the vehicle  176  can provide the same operating characteristics and advantages provided by the vehicles  50  and  150  when cornering, as discussed above. 
         [0126]    The embodiments of the present invention, including that of  FIG. 9 , provide positive dynamic camber to the vehicle.  FIG. 9  shows the tie structure  180  tilted outwardly relative to the curve (right hand direction) and the body structure  180  tilted inwardly into the curve (left hand direction) to a greater extent than the outward tilt of the tie structure. As a result of such tilting of the tie structure and body, and the interconnection of the tie structure to the wheel assemblies  182  and  184  and the connection of the strut assemblies  232  to the body above the roll center  186 , the wheels are tilted inwardly into the curve, providing positive dynamic camber. As will be appreciated, this improves the traction, turning and cornering abilities of the vehicle. 
         [0127]    The body structure  178  is also capable of pitching relative to the tie structure by rotation of the body about transverse pivot axis  278 . In this regard, the rods  216 B may rotate relative to the center bar portion  216 A. Alternatively, the pivot pins  217  extending outwardly from the rods  216 B may pivot relative to the slide blocks  218 . Since the transverse pivot axis  278  is located above the center of gravity  236 , during braking a longitudinal force is imposed on the springs of the vehicle  174  in a forwardly direction at the elevation of the center of gravity  234 . In the present invention such longitudinal force will tend to cause the body to pivot about transverse axis  278 , so that the rear end of the body tends to lower, while the front end of the body tends to rise, thereby maintaining significant load on the rearward torsion bar assemblies. It will be appreciated that during hard acceleration the opposite effect occurs, thereby maintaining significant loading on the front wheels of the vehicle. 
         [0128]    Also, during hard braking, or perhaps during a crash or impact, the body structure  178  is capable of moving longitudinally relative to the tie structure by the sliding of the slide block plates  228  relative to the slideway  220 . Such sliding movement can reduce the effect of a crash on the body, and in particular on the occupant(s) of the vehicle. This may be very significant if the vehicle construction shown in  FIG. 9  is employed in a racing vehicle. 
         [0129]    Rather than relying solely on compression of the bumper assemblies to cause the body  178  to shift relative to the tie structure, a powered system might be employed. In this regard, one or more hydraulic pumps can be utilized to force fluid into and out of linear actuators  254  when it is desired to cause the body  178  to be longitudinally shifted, for instance when accelerometers or other sensors indicate that a crash of the vehicle is occurring or may be imminent. The hydraulic pump can be utilized in conjunction with the bumper assemblies  240  or may be employed in lieu of such bumper assemblies and the associated fluid lines interconnecting the bumper assemblies to the linear actuators. 
         [0130]      FIGS. 10 and 11  disclose a further embodiment of the present invention wherein vehicle  50 C includes a body  52 C mounted on a suspension system  54 C, which in turn is supported by forward wheel assemblies  56 C and rearward wheel assemblies  58 C. A tie structure  60 C is interposed between the vehicle body  52 C and the wheel assemblies  56 C and  58 C. The tie structure  60 C extends longitudinally along a lower elevation of the vehicle  50 C and is interconnected to the body through a plurality of pivoting arm assemblies  302  to enable the body to roll and pitch relative to the tie structure  60 C. 
         [0131]    As shown in  FIGS. 10 and 11 , the tie structure may be of generally rectangular construction having forward and rearward panel sections  284  and  286  interconnected by longitudinal side panel sections  288 . The tie structure  60 C may be constructed by tubular components, plates or other appropriate structural members and materials. The tie structure may be connected to hub carriers  76 C of the forward and rearward wheel assemblies  56 C and  58 C in a manner described above with respect to  FIGS. 1 ,  2 , and  3 . As such, the construction and operation of the pivot arm assembly  68 C will not be repeated here. Also, an anti-roll bar  289  or other device can be used between the pivot arm assemblies and the tie structure of simply between the pivot arms themselves. Such anti-roll bar  289  is shown at the rear of the vehicle. A similar anti-roll bar can be used on the front of the vehicle. Such anti-roll bar includes a central length  289 A that is mounted to the rear of the tie structure  60 C and end arms  289 B that extended rearwardly and outwardly from the central section to be attached to corresponding hub assemblies of rear wheel assemblies  58 C. 
         [0132]    The body  52 C may be supported from the wheel hub assemblies by forward spring/shock absorber assemblies  70 C and rearward spring/shock absorber assemblies  80 C in a manner similar to that shown in  FIGS. 1 and 2 . The upper ends of the spring/shock absorber assemblies are connected to a structural member(s)  72 C of the body. It will be appreciated that rather than being constructed as a solid unit, the structural member  72 C may be of tubular or other type of construction, thereby to minimize its weight while still providing sufficient structural integrity to carry the loads imposed thereon, not only by the static weight of the vehicle  50 C, but also to carry the dynamic loads imposed on the vehicle during travel, including during cornering, as well as during acceleration and braking. 
         [0133]    As shown in  FIG. 10 , the suspension system  54 C may utilize forward and rearward steering assemblies  290  and/or  292  to steer the forward and rearward wheels. The forward and rearward steering assemblies may be of similar construction, and thus, only the construction of the forward steering assembly will be described with the understanding that the rear steering assembly is of similar construction and operation. The forward steering assembly  290  may include a rack and pinion subassembly  294 . The outer ends of the rack  296  are connected to the adjacent hub carrier  76 C by steering links  298  in a manner well known in the art. The rack and pinion subassembly  294  is mounted on the forward portion of the tie structure  60 C by a pair of forward-extending mounting brackets  300 . 
         [0134]    It is to be understood that other systems may be used to steer vehicle  50 C or the other vehicles of the present invention. For example, steering can be carried out by connecting the steering components electrically rather than using a rack and pinion. In this regard, rather than being connected to a vehicle steering wheel by a mechanical linkage arrangement, a linear actuator may be used to power the rack  296 . Moreover, electrical linear actuator may be used to power the steering arms, thereby eliminating the need for a rack. 
         [0135]    Referring also to  FIG. 13 , the body  52 C may be mounted to the tie structure  60 C by four arm assemblies  302 , located at each of the four corner portions of the tie structure  60 C. Each of the arm assemblies  302  may include a generally triangularly shaped arm structure  304  coupled to the tie structure by a pivot shaft  306  that closely engages through the interior of a tubular base member  307  to engage aligned clearance holes provided in mounting ears  308  fixed to the tie structure. The pivot shaft  306  defines a pivot axis  309  about which the arm structure  304  is able to pivot relative to the tie structure. The arm structure  304  also includes a pair of arms  310  that extend from the ends of the base  307  towards the apex of the arm structure. The distal apex ends of the arms  310  intersect a tubular collar  312  oriented substantially perpendicularly to cylindrical base member  307  but in planar alignment with the base member so that the central axis of collar  312  is in the same plane as the central axis of base member  307 . The collar  312  may be sized to receive a close-fitting cylindrical bushing  314  having a plurality of diametric cross-holes  316  formed along the bushing and spaced apart to correspond with the spacing of corresponding diametric cross-holes  318 , provided in collar  312 . Crossbolts  319  extend through the bushing cross-holes  316  and through corresponding collar cross-holes  318  to retain the bushing  314  in engagement with collar  312  at a desired relative position therebetween. It will be appreciated that the effective length of the arm structures  304  may be varied depending on which of the cross-holes  316  are in alignment with the cross-holes  318 . It will also be understood that the extent of relative engagement between bushing  314  and collar  312  may be controlled by other structures. For instance, the bushing  314  can be formed with external threads (not shown) to mate with internal threads (not shown) formed in collar  312 . 
         [0136]    One purpose of being able to adjust the effective lengths of the arm assemblies is to change the elevation or other locations on which the arm assemblies can be mounted on the tie structure  60 C, which changes the nominal angular orientation of the arms and thus the amount that the body is allowed to roll and pitch relative to the tie structure. 
         [0137]    Also, the nominal length of the forward arm assemblies can be changed relative to the rear arm assemblies to move the location of the pitch center of the vehicle fore and aft, as desired. This will affect the relative loading on front and rear wheel assemblies during braking and acceleration. 
         [0138]    The arm assembly  302  also includes an end connection knuckle  320 , having a stub shaft portion  322  sized to closely and rotatably engage within a radial bearing or bushing  324  disposed within the adjacent end of bushing  314 . The stub shaft is allowed to rotate relative to the bushing  324 , but not move longitudinally relative to the bushing, being held captive by a snap ring or other well-known means (not shown). The connection knuckle  320  also includes a collar section  326 , disposed transversely to stub shaft  322  and having an aperture therein for receiving a crosspin  328  that engages through close-fitting openings formed in mounting ears  330  fixed to the body structural assembly  72 C. An elastomeric bushing  331  may be interposed between the crosspin  328  and the mounting bar ears  330  to provide some insulation therebetween. Similar bushings can be used between pivot shaft  306  and mounting ears  308  or at other joint locations of the arm assembly  302 . 
         [0139]    As shown in  FIG. 10 , the two forward arm assemblies  302  are oriented in a rearward and inward direction relative to the vehicle  50 C, and likewise, the two rearward arm assemblies  302  are oriented in the forward and inward direction. The forward arm assemblies  302  are oriented such that the central axis  329  extending through collar  312  and the apex of the arm assemblies (and perpendicular to pivot shafts  306  and shafts  328 ) will intersect substantially at the longitudinal centerline  332  of the body  52 C and tie structure  60 C. The rear arm assemblies  302  are positioned in a similar orientation. 
         [0140]    It is to be understood that the arm assemblies can be positioned at angles other than as shown in plan view on  FIG. 10 , thereby to change the location of the pitch center and/or roll center of the vehicle. For example, the arm assemblies can be positioned so that their central axes all intersect at a common point along the longitudinal center line  332 . 
         [0141]    The body  52 C may be supported relative to the forward and rearward wheel assemblies  56 C and  58 C by forward spring/shock absorber assemblies  70 C and rearward spring/shock absorbers  80 C in a manner similar to that shown in  FIGS. 1 and 2 . As such, the structure and operation of the forward and rearward spring/shock absorber assemblies will not be repeated here. 
         [0142]    Also, the vehicle  50 C may be driven by an engine  88 C through a transmission  90 C and drive shaft  92 C in a manner similar to that shown in  FIGS. 1 and 2 . Accordingly, the construction and operation of these components will also not be repeated here. 
         [0143]    Rather than being carried by the tie structure  60 C, the engine  80 C and transmission  90 C may be carried instead by the body  72 C without departing from the spirit or scope of the present invention. In certain situations, mounting the engine and transmission on the body rather than on the tie structure might be advantageous to the construction and performance of the vehicle. For example, it may be easier to obtain access to the engine and transmission if located on the body rather than on the tie structure. Also, by locating the engine and drive train on the body, a larger portion of the weight of the vehicle rolls about the roll center and pitches about the pitch center during operation of the vehicle. This configuration can result in larger dynamic loading on the vehicle tires. 
         [0144]    In operation, as vehicle  50 C rounds the corner, the body  52 C is capable of tilting relative to the tie structure  60 C about a longitudinal axis  332  defined by the intersection of the forward and rearward arm assemblies due to the ability of the arm assemblies to pivot relative to the tie structure and the body in the up and down directions only, as well as the connector knuckle of the arm assembly to rotate about collar  312  along axis  329 . Moreover, the elevation of the longitudinal axis  332  corresponds to the elevation in which the axes  329  of the A-arm structures  304  intersect each other, which elevation is above the center of gravity  329 A of the vehicle. Accordingly, when the vehicle  50 C rounds the corner, the body  52 C will pivot about longitudinal axis  332  in the direction inwardly of the curve (towards the center of curvature of the curve), in a manner similar to the embodiment of the present invention described above. Also, as will be appreciated, the arm assemblies  302  enable the body  52 C to pitch relative to the tie structure  60 C during braking or accelerating in the manner of previous embodiments of the present invention described above. 
         [0145]    In addition, when vehicle  50 C is cornering, the tie structure  60 C is capable of swinging slightly outwardly due to the pivoting of the pivot arm assemblies  68 C, thereby reducing the rate of force transfer of the centrifugal force through the tie structure, thereby delaying the time that the jacking effect fully acts on the body. As a result, as described above, the effective roll reaction center of the vehicle  50 C is at an elevation below the elevation of longitudinal axis  332 , resulting in a lower jacking effect being imposed on the vehicle during cornering. Thus, the construction of vehicle  50 C can provide the same advantages when cornering as provided by the vehicles described above, including vehicles  50  and  150 . 
         [0146]    In addition, it can be appreciated that through the present invention, the arm assemblies  302  can independently move relative to each other. Thus, for example, during cornering, the arm assemblies located on the inside of the vehicle may move to a less steep or lower angle of inclination due to the inward tilting of the body and outward tilting of the tie structure relative to the inclination of the arm assemblies at the outside of the vehicle. Also, the arm assemblies on the inside of the vehicle drop down farther than the outside arms rise up. 
         [0147]    It will be appreciated that if the arm assemblies are nominally adjusted to have a lower angle of inclination, more body movement will be achieved per movement of the arms. 
         [0148]    It will be appreciated that the arm assemblies  302  may be replaced with other structures, for example, a linear actuator. Such linear actuator can be extended and retracted in a manner similar to extending and retracting the arm assemblies  302 , as discussed above. Also, the arm assemblies  302  themselves can be modified so that their lengths can be automatically adjusted, for example, by the use of hydraulic or electric actuators to move the knuckle connector relative to the A-arm structure. 
         [0149]      FIG. 13  illustrates a further embodiment of the present invention, wherein a vehicle  50 D is designed to allow a body  52 D to slide longitudinally relative to the tie structure  180 A upon an impact force applied to the vehicle in a direction away from the impact force, for instance, during a collision. In addition, the passenger seats  333 A and  333 B are designed to slide upon an impact load applied to the vehicle. The tie structure  180 A is illustrated as of generally rectangular construction similar to the construction of the tie structure  180  shown in  FIGS. 6 ,  7  and  8 . As such, the construction of tie structure  180 A will not be repeated here. 
         [0150]    The vehicle  50 D may include a forward bumper assembly  334  that is shaped similarly to bumper assembly  240  shown in  FIGS. 6-8 . In this regard, the bumper assembly  334  may be constructed similarly to bumper assembly  240  except that upon impact, the fluid in the bumper assembly may simply be expelled into the ambient air rather than utilized to move the body  52 D relative to the tie structure  180 A. Likewise, vehicle  50 D may include a rear bumper assembly  335  that is constructed and shaped similarly to the rear bumper assembly  264  shown in  FIGS. 6-8 . The rear bumper assembly  335  can also be designed to expel the fluid therein into the ambient air rather than being utilized to shift the body  52 D relative to the tie structure  180 A. 
         [0151]    It is to be understood that the forward and rearward bumper assemblies  332  and  334  also can be of other constructions. For instance, these bumper assemblies can be composed of crushable or collapsible material or structures to absorb at least some of the energy from collisions or other impact loads imposed on the vehicle. Also, collapsible material  337  may be mounted on body  52 D to absorb energy in case of a crash. In  FIG. 13 , such material is shown at the front and back of the body  52 D. 
         [0152]    In a manner similar to that shown in  FIGS. 6-8 , the tie structure  180 A is supported by forward and rearward wheel assemblies  182 A and  184 A with the use of lower control arm assemblies  200 A that may be pinned to a mounting bracket  202 A carried by the upper side beams  188 A of the tie structure. The lower ends of the control arms  200 A are coupled to the wheel assemblies  182 A and  184 A in the same manner as in  FIGS. 6-8 . Such coupling can be accomplished to enable the forward wheel assemblies  182 A to be steerable, in a conventional manner. 
         [0153]    Forward and rearward slide assemblies  336  are imposed between the tie structure  180 A and the body  52 D. The slide assemblies  336  may be of many different constructions, including composed of a slideway  338  mounted on the upper side of tie structure top side beams  188 A to slidably receive a slide  340  secured to the underside of body  52 D. The slide assemblies  336  may be designed to require a baseline impact load to be imposed on the vehicle  50 D before permitting the body to slide relative to the tie structure. This can be accomplished in many well-known manners. For example, as a result of the threshold impact load that is imposed on the bumper assemblies  334  or  335 , the body  52 D can be permitted to continue to move somewhat in its same direction of travel rather than coming to an abrupt halt or before beginning to move away from the impact. If the impact load is applied to the body, the body can slide relative to the tie structure in the direction away from the impact force. As such, the forces imposed on the vehicle passengers is significantly less than in a conventional vehicle. 
         [0154]    It will be appreciated that the slide assemblies  336  may be constructed to allow the body  52 D to also move laterally relative the tie structure  180 A, for example during a crash or collision. The slide assemblies can include a transverse slideway (not shown) mounted to the body that would allow lateral movement of such slideways relative to slide  340 . 
         [0155]    In addition to, or in lieu of, the slide assemblies  336 , further slide assemblies  342  may be utilized between passenger seats  333 A,  333 B and body  52 D. The slide assemblies  342  can be of many known constructions. For example, a slideway assembly  344  may be mounted on the lower floor of the vehicle body and a slide assembly  345  attached to the lower bottom side of the passenger seats  333 A and  333 B. As with slide assemblies  336 , the slide assemblies  342  can be designed to require a threshold impact load to be imposed on the vehicle before the passenger seats  333 A and  333 B are permitted to move relative to the body  52 D. As noted above, this can be accomplished in many different ways to provide the same advantage provided by slide assembly  336 , i.e., to permit the vehicle passengers to continue to move to a certain degree along their same path of travel toward an impact load when the impact load is applied to the vehicle tie structure. In addition, the slide assemblies  342  will enable the passengers to continue to move in their direction of travel if instead of an impact load being applied to the tie structure, such impact load is applied to the body  52 D, thereby lessening the impact force imposed on the passengers. This could reduce the injuries caused to the vehicle passengers during a collision or other accident. 
         [0156]    It will be appreciated that, rather than mounting the seats  333 A and  333 B on slide assembly  342 , the seats might instead be mounted on a four-bar linkage arrangement or other type of structure to enable the seats to swing relative to the body during a crash or other significant impact load imposed on the vehicle. It will be appreciated that to accomplish such swinging movement, parallel swing arms may extend upwardly from the vehicle floor or downwardly from the vehicle roof, or laterally from the vehicle panels or structures, to support the seats during normal use and also to permit swinging movement of the seats during a crash. 
         [0157]    As a further alternative, seats  333 A and  333 B may be pivotally mounted to the overhead portion of the body  52 D. In this regard, a bracket may extend between the rear upper portion of the seats  333 A and  333 B and the overhead portion of the body  52 D. 
         [0158]    It is appreciated that the body  52 D, shown in  FIG. 13 , is shown schematically. The body  52 D can be of various other shapes without departing from the spirit or scope of the present invention. In this regard, the body  52 D might be shaped generally in the manner of the body  52 , shown in  FIGS. 1 and 2 . Moreover, the body  52 D may be constructed to be easily removable from the tie structure  180 A. In this regard, quick-release connectors can be utilized to connect the body  52 D to the tie structure at the slide  340 . 
         [0159]    It will be appreciated that for the body  52 D to move or slide relative to the tie structure, the body may require more structural integrity than in the typical automobile currently being manufactured. As such, it may not be necessary to design the body with crushable panels at the ends or sides thereof, although such crushable panels are an option. 
         [0160]      FIGS. 14 ,  15  and  16  schematically illustrate a further embodiment of the present invention, wherein a vehicle  960  includes a body  962  mounted on an underlying tie structure  964 , which is supported by wheel assemblies  966 . The tie structure may extend substantially the length of the body  962  or may be composed of a forward section at the forward end of the vehicle and a separate rearward section at the rearward end of the vehicle. The body is capable of rolling relative to the tie structure, which preferably extends longitudinally of the vehicle and transversely across the vehicle at a lower elevation thereof. A lower control arm assembly  968  extends outwardly from a corner of the tie structure to the underside of hub assemblies  970  of the wheel assemblies  966 . 
         [0161]      FIGS. 14 ,  15  and  16  illustrate the forward end portion of the vehicle  960 . The rearward end portion of vehicle  960  may be constructed similarly thereto. The control arm assembly  968  may be torsionally loaded relative to the tie structure  964  in a manner that is well known in the art, for instance as described above and illustrated in  FIG. 3 . 
         [0162]    Swing arm assemblies  972  extend upwardly from corner locations of the tie structure  964  to pivotally couple to the adjoining portion of body  962 . The swing arm assemblies  972  consist of longitudinally separated arms  972 A and  972 B interconnected by a pair of parallel rods or tubes  972 C. The upper end portions of the arms  972 A and  972 B are pinned to the lower portion of the body  962 , with the lower end portions of the arms pinned to side sections of the tie structure  964 . As shown in  FIG. 14 , the swing arm assemblies  972  are sloped towards each other in the upward direction so that lines extending therefrom intersect at the roll center  978  of the vehicle. The swing arm assemblies  972  allow the body  962  to roll relative to the tie structure  964  while restricting relative longitudinal movement between the body and the tie structure. By this construction, the tie structures  964  and swing arm assemblies  972  can be incorporated into existing vehicles or designed into new vehicles without a radical change in design from existing vehicles. 
         [0163]    Continuing to refer to  FIGS. 14 ,  15  and  16 , the vehicle  960  includes a propulsion engine/motor  974  that is carried by the tie structure  964 . A drive train  975  may be interconnected between the motor/engine  974  and the wheel assemblies  966  in a manner well known in the art. Also, the motor/engine may be located near the forward end of the vehicle, near the rearward end of the vehicle, or at a location therebetween. The body  962  may be supported by strut assemblies  976  extending upwardly from hub assemblies  970  for connection to an upper portion of the body  962 . The strut assemblies may be designed so that the roll stiffness of the body  962  is not as stiff as the roll stiffness of the tie structure. 
         [0164]    With respect to the operation of the vehicle  960 , applicant notes that the roll center  978  of the vehicle  981  is at a location defined by the intersection of lines extending longitudinally from swing arms assemblies  972 , which is at an elevation substantially above the center of gravity  980  of the vehicle. As such, when the vehicle  960  rounds a corner, a centrifugal force is applied thereto at the center of gravity  980 , which is at an elevation below the roll center  978 . As such, the body  962  tilts inwardly toward the center curvature of the curve about the roll axis  978 . When this occurs, the tie structure simultaneously tilts, to some extent, away from the center of curvature, which tends to cause the roll center  978  to shift outwardly somewhat relative to the center of a curve being negotiated, but not far enough to negate the inward tilting motion of the body  962 . The advantage of the tie structure moving outwardly slightly during cornering is that during such movement, the roll center  978  does not serve as a roll center about which centrifugal forces act to tip the vehicle outwardly so that the rate of centrifugal force transfer through the vehicle is reduced. It will be appreciated that the relative outward tilt of the tie structure in relationship to the inward tilt of the body can be altered by controlling the various components of the vehicle suspension system, including the torsion load at the inward ends of the trailing links  968  and the load-carrying capacity and stiffness of the strut assemblies  972 . 
         [0165]    Vehicle  960  also provides the advantage of positive dynamic camber when cornering. In this regard, as shown in  FIG. 14 , the body  962  is tilted upwardly at the side thereof toward the outside of the curve while the tie structure is tilted somewhat downwardly relative to the outside of the curve, with the tilt of the tie structure being less than the tilt of the body due to the relative greater stiffness of the torsion load on arm assemblies  968  vis-à-vis the strut assemblies  976 . The upward tilt of the body will tend to move the upper portion of the inside wheel inwardly into the curve as well as move the upper portion of the outside wheel inwardly relative to the curve. As a result, both the wheels of the vehicle tend to tilt inwardly relative to the curve providing positive dynamic camber, thereby improving the traction of the vehicle during cornering. 
         [0166]    It will also be appreciated that by mounting the motor/engine  974  and corresponding drive train components on the tie structure, less plunge is required for the drive line interconnecting the motor/engine to the drive wheels, in relationship to the plunge required if the motor/engine were mounted on the body. As noted above, vehicle  960  is designed so that the tie structure  964  tilts outwardly to a lesser degree in cornering than does the body  962  tilt inwardly during cornering. Further, by mounting the motor/engine solely on the tie structure, it would be easier to adapt the present invention to existing vehicles. 
         [0167]      FIG. 17  diagrammatically illustrates a further embodiment of the present invention wherein a vehicle  981  includes a body  982 , mounted on an underlying tie structure  983 , which is supported by wheel assemblies  984 . As in the embodiment shown in  FIGS. 14 ,  15  and  16 , the tie structure  983  may extend substantially the entire length of the body  982 , or may be composed of a forward section at the forward end of the vehicle and a rearward section at the rear end of the vehicle. As also in the vehicle  960  shown in  FIGS. 14 ,  15  and  16 , in the vehicle  981 , the body  982  is capable of rolling relative to the tie structure. 
         [0168]    Control arm assemblies  985  extend outwardly from the sides of the tie structure to the underside of hub assemblies  986  of wheel assemblies  984 . The control arm assemblies  985  may be torsionally loaded relative to the tie structure  983  in a manner as described above. 
         [0169]    Swing arm assemblies  987  extend upwardly from tie structure  983  to pivotally couple through the adjacent portions of body  982 . The swing arm assemblies  987 , as illustrated, may consist of A-arm assemblies similar to those shown in  FIGS. 10 ,  11  and  12 . In this regard, the swing arm assemblies  987  may be positioned to extend upwardly towards the longitudinal center of the body  982  and also the forward swing arm assemblies may extend towards the rear of the vehicle  981 , whereas the rear swing arm assemblies may be oriented to slope forwardly towards the forward end of the vehicle  981 . In this manner, the swing arm assemblies  987  may allow the body  982  to roll relative to the tie structure  983  and also permit the body to pitch relative to the tie structure in a manner somewhat similar to the vehicle  500  shown in  FIGS. 10 and 11 . 
         [0170]    As in vehicle  960  shown in  FIGS. 14 ,  15  and  16 , the vehicle  981  may be constructed so that the stiffness of the control arm assemblies  985  is greater than the stiffness of the strut assemblies  988  used to support the body relative to the wheel assemblies  984 . In this manner, when the vehicle is rounding a corner, the centrifugal force is applied thereto at the center of gravity  989 , which is at an elevation below the roll center  989 A of the vehicle, causing the body to tilt inwardly toward the center of the curve. When this occurs, the tie structure simultaneously tilts, to some extent, away from the center of the curve, thereby tending to cause the roll center  989 A to shift outwardly somewhat relative to the center of the curve, but not far enough to negate the inward tilting motion of the body  982 . As in other embodiments of the present invention, advantageously the slightly outward movement of the tie structure during cornering prevents the roll center  989 A from serving as a roll center about which centrifugal forces act to tip the vehicle outwardly, so that the rate of centrifugal force transfer through the vehicle is reduced. This same advantage applies during vehicle pitching. 
         [0171]    Moreover, vehicle  981  also provides the advantage of positive dynamic camber when cornering. In this regard, the vehicle  981  operates in a manner very similar to vehicle  960 , described above, and thus such description will not be repeated here. 
         [0172]    As a further matter, in vehicle  981 , the motor/engine  989 B and the corresponding drive train components  989 C may be mounted on the tie structure  983  rather than being carried by the body or other parts of the vehicle. As a consequence, the drive train is required to accommodate less relative movement between the engine and the drive wheels than would be required if the motor/engine were mounted on the body. 
         [0173]      FIG. 18  illustrates another embodiment of the present invention wherein a vehicle  1300  includes a body  1302  supported above an underlying tie structure  1304  by pairs of diagonal control sliders  1306 . The tie structure  1304  may be in the form of a solid axle extending transversely between wheel assemblies  1308 . Also the lower end of the control sliders  1306  may be mounted below the tie structure/axle  1304  by use of brackets  1310  thereby to lower the pitch center and/or roll center  1312  as low as possible. As in other embodiments of the present invention, the pitch center and/or roll center is defined by the intersection of lines constituting extensions of the control sliders  1306 . 
         [0174]    The control sliders  1306  are illustrated in  FIG. 19  as constituting an adjustable hydraulic or fluid spring-loaded actuator assembly having a cylinder portion  1314  housing a piston  1316  which is connected to a piston rod  1318  which extends outwardly from the cylinder. A relatively stiff spring  1320  or other type of resilient means loads the piston  1306  against stop  1322  thereby dividing the cylinder  1314  into first and second chambers  1324  and  1326 . The chambers  1324  and  1326  may be filled with a fluid that passes from one side of piston  1316  through passages  1327  that limit the speed that the piston may move relative to the cylinder  1314 , for instance if one control slider  1306  is unloaded due to its corresponding wheel  1308  hitting a pothole and at the same time the body rolling or pitching. Controlling the rate that the piston  1316  can move within cylinder  1314  will make sure that there will be resistance to such rolling or pitching action. 
         [0175]    It will be appreciated that the control sliders  1307  and similar components described herein may be of other constructions. For example, the control sliders may be constructed with a fluid that can be changed in viscosity as desired very quickly if not almost instantaneously, so as to change the operational characteristics of the control sliders, struts or other similar components of the present invention. One example of such fluid construction includes magnetic properties that can be changed or controlled electrically or electronically. 
         [0176]    Optionally, linear controllers  1328  may extend between the tie structure and the body to control the tilt and/or pitch of the body. The controllers have a spring rate that is “softer” than the control sliders  1306  to allow the tie structure to react to road bumps without transferring all of the “bumps” to the body. However, the function of the linear controllers  1328  may be carried out by the control sliders  1306 . In this regard, the control sliders can be of variable spring rates, perhaps having a softer spring rate when accommodating road discontinuities but having a much stiffer spring rate when the body rolls during cornering or pitches during acceleration or hard braking. Sensors can be utilized on the vehicle to sense road bumps as well as the body roll during cornering and body pitching during braking and acceleration. In response thereto, the characteristics of the control slider  1306  are automatically adjusted so as to react to the particular external force being applied to the vehicle, whether road bumps or corner rolling or pitching due to braking or accelerating. It will be appreciated that by this construction a tie structure such as described above with respect to other embodiments of the present invention, for instance shown in  FIG. 17 , may not actually be required, thereby simplifying the construction of vehicles made in accordance with the present invention. 
         [0177]      FIGS. 20 ,  21 ,  22  and  23  illustrate a further embodiment of the present invention, wherein vehicle  346  includes a body  348  mounted on an underlying tie structure  350  supported by wheel assemblies  352 . The tie structure  350  includes a lower hollow transverse crossmember  354  having a torsion bar  356  extending therethrough. The outer ends of the torsion bar extend beyond crossmember  354  to rigidly couple to the rearward ends of forward leading arm assemblies  358 . The opposite ends of the leading arm assemblies are pivotally coupled to the lower portions of hub assemblies  360  of a wheel assembly  352 . The torsion bar  356  allows for controlled relative vertical movement between the tie structure  350  and the wheel assemblies  352 , for instance when traveling over a bump or cornering. 
         [0178]    The tie structure  350  is connected to the body  348  by a pair of lower swing arm assemblies  362 . The swing arm assemblies may be of numerous, different constructions. For example, in  FIGS. 20 and 21  the swing arm assemblies  362  are in the form of A-arms having their lower ends coupled to the tie structure crossmember  354  by a pivot pin  364  that is carried by pivot block  366  attached to the tie structure crossmember  354 . The upper, opposite ends of the swing arms  362  are pinned to lower portions of a body structural member  368 . It will be appreciated that the swing arms  362  keep the body  348  from moving longitudinally relative to the tie structure  350  while allowing the body to move laterally as well as pivot about a longitudinal axis relative to the tie structure  350 . Also, the swing arm assemblies are oriented so that they are in alignment with the roll center  367  of the vehicle, which is at an elevation above the center of gravity  384  of the vehicle. 
         [0179]    The tie structure  350  further includes upright posts  370  extending upwardly from the tie structure crossmember  354 . The lower ends of the posts can be attached to the crossmember  354  by bolts  357  to enable the posts to pivot in the lateral direction above the bolts. The upper ends of the posts  370  are coupled to a central location on the body structural member  368  by a pair of link arms  372 A and  372 B. The outer ends of the link arms  372 A and  372 B are pinned to the posts  370  at selective locations along the height of the posts, with the particular location of such pin connection selected for adjusting the camber imposed on the vehicle  346 . The center, inward ends of the link arms  372 A and  372 B are jointly pinned to the body structural member  368  to pivot about a longitudinal axis  374  of the vehicle. As an alternative, the link arms  372 A and  372 B may be shortened to be pinned to the body structure member  368  at laterally spaced apart locations (not shown). 
         [0180]    The upper end portions of the posts  370  are supported by upper leading arms  376 . The inward ends of the leading arms  376  are pinned to respective posts  370  by cross pins  378  extending through a transverse opening formed in the posts and through aligned openings of a yoke formed in the trailing arm  376 . The outer, forward ends of the upper leading arms  376  are connected to wheel hub assemblies  360  by ball joints  380  in a well-known manner. It will be appreciated that from their connection to posts  370 , the upper leading arms  376  extend laterally outwardly, forwardly and downwardly to their connection with corresponding hub assemblies  360 . 
         [0181]    The body  348  is also supported relative to the tie structure  350  by spring/shock absorber assemblies  382 . The lower ends of the spring/shock absorber assemblies are connected to lower leading arms  358  by ball joints  383  in a conventional manner, and correspondingly the upper ends of the spring/shock absorber assemblies are connected to the body structural member  368  also by ball joints  385  in a conventional manner. 
         [0182]    In operation, when vehicle  346  rounds a corner, a centrifugal force is applied thereto at the center of gravity  384  which is at an elevation below the elevation of the roll center  367 . As such, the body  348  will tilt inwardly toward the center of curvature of the curve about axis  374  and compress the inside spring/shock absorber assemblies. When this occurs, the tie structure simultaneously tilts, to some extent, away from the center of curvature, which tends to cause the longitudinal axis  374  to shift outwardly of the center of curvature somewhat, but not far enough to negate the inward tilting of the body  348 . The advantage of the tie structure moving outwardly slightly during cornering is that during such movement the rate of force transfer through the vehicle is less than if the tie structure did not tilt. During such tie structure movement, the longitudinal axis  374  does not serve as the roll reaction center about which the forces would be acting to tip the vehicle outwardly. It will be appreciated that the relative outward tilt of the tie structure in relation to the inward tilt of the body can be altered by controlling the stiffness of the various components of the vehicle&#39;s suspension system, including the torsion bar  356  and the spring/shock absorber assemblies  382 . 
         [0183]      FIGS. 24 ,  25  and  26  diagrammatically disclose a further embodiment of the present invention wherein a vehicle  390  includes body  392  mounted on/carried by a tie structure  394 , which in turn is carried by wheel assemblies  396 . The tie structure includes a transverse crossmember subassembly  400  composed in part of a cross tube  402 . The inward base portion  404  of a lower A-arm assembly  410  engages within each end portion of the cross tube  402 . The base portion  404  is biased in the direction towards the adjacent outward end of the cross tube  402  by a compression spring  406 . The inward end of the compression spring presses against a piston  408  which is loaded toward the outer end of the cross tube  402  by any convenient means, for example by hydraulic pressure, linear actuator, etc. The opposite, outward end of the A-arm assembly  410  is coupled to a lower portion of wheel hub assembly  414  through the use of a ball joint  416 . 
         [0184]    The body  392  is connected to the underlying tie structure  394  by diagonally oriented link arms  418  that are pinned at their lower ends to outward end portions of the cross tube  402 . The upper, inward portions of the link arms are pinned to lower portions of body structural member  420 . The link arms  418  are oriented so that if extended in the inwardly direction they would intersect at point  422  along the transverse center line of the vehicle  390  corresponding to the roll center of the body. The body  392  is also supported by upper arm assemblies  424  having their lower ends carried by hub assemblies  414  and their upper ends coupled to the body structural member  420  by ball joints  426 . Body springs  427  are connected between hub assembly  414  and body  392 . 
         [0185]    The hub assemblies  414  may be steered by steering arms  428  that are coupled to the hub assemblies. The upper ends of the steering arms  428  extend rearwardly from the hub assemblies and are connected to the outer ends of a rod  432  extending outwardly from a center steering assembly  434  mounted at the upper portion of body structural member  420 . 
         [0186]    It will be appreciated that the vehicle  390 , when negotiated around a corner, responds quite similarly to vehicle  348  shown in  FIGS. 20-23 . In this regard, when rounding a corner a centrifugal force is laterally applied to the vehicle  390  at the center of gravity  436  which is at an elevation below intersection point  422  of the diagonal links  418 , causing the body to tilt about such intersection point inwardly toward the center of the curve to compress the inside springs. Correspondingly, the centrifugal force on the tie structure  394  tends to cause the tie structure to tilt somewhat in the outwardly direction relative to the center of the curve, which in turn tends to cause the crossmember subassembly  400  to tilt outwardly relative to the curve. During such movement of the tie structure, the intersection point  422  does not serve as a roll reaction center. The rate of centrifugal force transfer through the vehicle  390  is reduced relative to if the tie structure were not capable of such movement. 
         [0187]    As a further matter, it will be appreciated that the nominal location of the lower A-arms  410  can be varied relative to cross tube  402 , thereby to alter the ride height of the vehicle. Also, the nominal location of the lower A-arms  410  relative to the cross tube  402  can be used to vary the relative loads carried by the cross tube and the body springs  427 . 
         [0188]    The embodiments of the present invention shown in  FIGS. 24 ,  25  and  26  may be modified to provide an “active” suspension system. In this regard, the cross tube  402  and compression spring  406  may be replaced with a linear actuator, for example a hydraulic cylinder assembly (not shown) mounted transversely on tie structure  394 . Also, body springs  427  may be replaced with hydraulically actuated suspension cylinders positioned at locations corresponding to the body springs  427 . Such suspension cylinders may be controllable to increase or decrease their lengths, thereby to tilt the body  392  as desired, for instance when cornering. A control system (not shown) may be provided for sensing the direction, speed and acceleration of the vehicle  390  in controlling the roll of the vehicle as well as the lateral movement of the tie structure  394  in response to driving conditions, including cornering. For instance, when cornering, the hydraulic cylinders that replace body springs  427 , can be controlled to tilt the body inwardly into the curve rather than outwardly in the manner of a typical vehicle. Moreover, also when cornering, the linear actuators that replace the springs  402  may be activated to allow the tie structure to move somewhat laterally outwardly to prevent, at least initially, the roll center  422  of the vehicle from being the point through which the roll couple is generated, tending to tilt the vehicle about its outer wheels  396 . 
         [0189]      FIG. 27  schematically discloses a further embodiment of the present invention, wherein a vehicle  650  includes the body portion  652  supported on an underlying tie structure  654  extending across the vehicle between wheel assemblies  656 . The tie structure  654  may be of various constructions, including those constructions described herein. The tie structure  654  is interconnected to body  654  by diagonally oriented link arms  658  that are pinned at the lower ends to a tie structure  654  and pinned at their upward, inward ends to the body  652 . The link arms  658  are oriented so that if extended in the inward direction they would intersect each other at a point  660  along the transverse centerline of the vehicle  650  corresponding to the roll center of the vehicle, which is located above the center of gravity of vehicle  662 . 
         [0190]    The tie structure  654  is interconnected to the wheel assemblies  656  by lower control arms, also referred to as trailing arms  664 , which are pinned at their outward ends to wheel hub assembly  666  and also pinned at their inward ends to lateral portions of the tie structure. The nominal orientation of the trailing arm  664 , as well as the resistance to the pivoting of the trailing arm about its inward end portion, is accomplished by a crank arm  668  that is fixedly attached to the inward end portion of the trailing arm  664  so as to rotate about the inward connection point  667  of the trailing arm  664 . The distal end of the crank arm  668  is coupled to the distal end of a rod  670  projecting from the cylinder portion  672  of a double-acting linear control member  674 . 
         [0191]    A push rod  676  extends upwardly from a pivot connection  677  on a trailing arm  664  to pivotally interconnect with the laterally outward end of a crank arm  678  which is pivotally attached to a lateral portion of the body  652 . The opposite end of the crank arm  678  is coupled to a relatively soft linear control member  680 , with the opposite end of the linear control member coupled to a location on the body  652 . 
         [0192]    The body  652  is also supported by an upper control arm, such as trailing arm  682 , pinned at its inward end to the body  652  and pinned at its outward end to an upward strut extending upwardly from the wheel hub assembly  666 . 
         [0193]    It will be appreciated that vehicle  650  operates similarly to other vehicles of the present invention as illustrated and described herein, including vehicle  390  illustrated in  FIGS. 24-26 . In this regard, during cornering, the centrifugal force on the vehicle  650  acts through the center of gravity  662 , which is located below the roll center  660  of the vehicle, thereby causing the body  652  to tilt inwardly into the curve being negotiated. At the same time, the tie structure  654  tilts downwardly in the laterally outwardly direction, thereby causing a similar movement of the body and roll center  660  so that the roll center does not serve as the reaction center of the vehicle, thereby reducing the jacking effect acting on the vehicle. 
         [0194]    A further embodiment of the present invention is schematically illustrated in  FIG. 28  which includes certain aspects of the present invention shown in  FIGS. 20-23 . In this regard, the vehicle  440  includes a body having a structural portion  442  supported on an underlying tie structure  444 . The tie structure includes a cross tube  446  extending laterally across the vehicle to house a torsion bar  448  extending the full length of the cross tube and extending outwardly therefrom. The end portions of the torsion bar are connected to the inward end portions of leading arm assemblies  450 , with the outward ends of the leading arms coupled to hub assemblies  452  of wheel assemblies  454 . As discussed above, including with respect to  FIGS. 20-23 , the torsion bar  440  serves to support the tie structure relative to the wheel assemblies  454  and allow relative vertical movement between the tie structure and the wheel assemblies. Spring/shock absorber assemblies  456  extend upwardly from hub assemblies  452  to interconnect with overhanging portions of the body structural member  442  through the use of ball joints  458 . 
         [0195]    The body structural portion  442  is interconnected with the tie structure  444  by diagonal link arms  460 . The upper ends of the link arms are pinned to the body structural portion  442  at one of a plurality of selected locations  462 A,  462 B and  462 C. The lower, outward ends of the link arms may be pinned at a number of different locations on slide brackets  464  carried by, and may be adapted to slide relative to, cross tube  446  by engaging within slideways  465  extending along the upper portion of the tube  446 . Any convenient means can be provided to enable the brackets  464  to be moved along the cross tube  446 . In this regard, the brackets  464  may be moved while the vehicle is in operation by a powered system so as to change the location of the roll center of the vehicle in response to road or driving conditions. It also will be appreciated that by changing the position of the upper and lower ends of the link arms  460 , the elevation of the roll center  466  of the vehicle may be altered as well as the camber of the vehicle. Moreover, the tie structure  444  may be adapted to be retrofit in different vehicles. 
         [0196]    In operation, the vehicle  440  operates in a manner similar to vehicles  346  and  390  discussed above and results in substantially the same advantages provided by such vehicles, including the tilting of the vehicle body inwardly while cornering instead of outwardly in the manner of a traditional vehicle. 
         [0197]    A further embodiment of the present invention is illustrated in  FIG. 29 , wherein vehicle  520  may be constructed somewhat similarly to vehicles  50  and  150 , described above, but with the following differences. Vehicle  520  includes a body  522  supported by and carried above an underlying tie structure  524  which in turn is supported by wheel assemblies  526 . As in the tie structure  60  shown in  FIGS. 1 and 2 , the tie structure  524  may be generally in the form of a rectangular box-type structure that extends longitudinally along the lower elevations of the vehicle  520  between the hub carriers of the forward and rearward wheels  528  and  530 . However, the tie structure  524  differs from the tie structure  60  in that the tie structure  524  includes a forward section  524 F and a rearward section  524 R that telescopically engage with center section  524 C. Both the forward section  524 F and rearward section  524 R may include top and bottom side members  532  and  534  extending along both sides of the vehicle  520  and spaced vertically apart by forward vertical members  536  and rearward vertical members  538 . The top side members  532  and bottom side members  534  are transversely interconnected by crossmembers  539  that may be similar to crossmembers  108  and  110  of  FIGS. 1 and 2 . Also, as in  FIGS. 1 and 2 , a plurality of intermediate crossmembers (not shown) such as crossmembers  112  shown in  FIGS. 1 and 2  may also be utilized for reinforcing purposes. Further, additional reinforcing members (not shown) may be employed in the construction of the forward tie structure section  24 F and rearward tie structure section  24 R, as needed. The forward tie structure section  524 F and rearward tie structure  524 R may be constructed from any appropriate materials, such as tubing or channel stock. 
         [0198]    The tie structure center section  524 C may be constructed somewhat similarly to the forward tie structure section  524 F and rearward tie structure section  524 R in that such center tie structure section includes top side members  532 C and bottom side members  534 C that are vertically interconnected by vertical end members  540  and vertical intermediate members  542 . Also, appropriate crossmembers (not shown) may be utilized to transversely interconnect the top side members  532 C and bottom side members  534 C. The top side members  532 C and bottom side members  534 C may be tubular or otherwise hollow to telescopically receive the rearward end portions of the top side members  532  and bottom side members  534  of the tie structure forward section  524 F as well as the forward end portions of the top side members  532  and bottom side members  534  of the tie structure rearward section  524 R. A friction fit, shear pins or other well-known means may be utilized to retain a nominal engagement between the tie structure center section  524 C and the forward section  524 F and rearward section  524 R. 
         [0199]    The body  522  may be supported above tie structure  524  by a forward set of pivot arm assemblies  544  mounted on the tie structure center section  534 C at laterally spaced-apart locations as well as rearward pivot arm assemblies  545  also mounted on the tie structure center section  524 C at laterally spaced-apart locations. Such pivot arm assemblies may be similar in construction to pivot arm assemblies  302 , discussed above. The upper ends of the pivot arm assemblies  544  and  545  may be incorporated into a slider  546  that slidably engages within a slideway  548  incorporated into the lower portion of body  522 . Slider  546  and slideway  548  may be of various well-known constructions, some of which have been described above. 
         [0200]    Spring/shock absorber assemblies  550  extend upwardly from either the hub carriers of wheel assemblies  528  and  530  or from the tie structure  524  to body  522 . Such spring/shock absorber assemblies  550  may be similar to spring/shock absorber assemblies described above, including part numbers  70 ,  80 ,  232  and  234 . The spring/shock absorber assemblies  550  may be designed to carry a select proportion of the weight of the body  522  relative to the portion of such body weight carried by the pivot arm assemblies  544  and  545 . 
         [0201]    The vehicle  520  may include a drive system  552  preferably located at the center portion of the vehicle, though the drive system could also be positioned at the front or rear of the vehicle, if desired. The drive system may include an internal combustion engine, an electric motor, or other type of power plant. The drive system may also utilize a transmission and drive train for transmitting the drive torque from the transmission to the wheels to be driven. The drive train can be designed to accommodate the relative movement between the tie structure center section and the tie structure forward  524 F and/or rearward  524 R sections. 
         [0202]    Rather than utilizing drive system  552 , the vehicle  50  may be powered by electric motors incorporated into the hub assemblies of the forward and rearward wheels. Such motors may be similar to those described above with respect to  FIGS. 1 and 2 . An example of such electric motors is described in U.S. Pat. No. 5,438,882. 
         [0203]    In operation, if the vehicle  520  is involved in an accident or impact load is otherwise imposed on the tie structure  524 , for instance at the forward end of the vehicle, the tie structure forward section  524 F may telescopically engage further within tie structure center section  524 C to absorb some of the impact energy, thereby reducing the effect of the crash on vehicle passengers as well as reducing the potential damage to the vehicle from the crash. As the tie structure forward section  524 F telescopes within center section  524 C, the body  522  can move rearwardly relative to the tie structure center section  524 C by virtue of the movement of the slides  546  within slideway  548 . After the crash, the forward tie structure section  524 F may be extended relative to tie structure section  524 C to resume its nominal position without extensive effort. Also, during a crash, the body  522  can move away from the point of impact on the vehicle. 
         [0204]    It is to be appreciated that vehicle  520  can be constructed with the body  522  composed of telescoping sections to help absorb some of the energy of a crash in much the same way as the structure discussed above. Also, by this construction, the body and tie structure can be designed to telescope in unison so that relative movement is not needed between the body and tie structure at the locations that they are joined together. 
         [0205]      FIGS. 30 and 31  schematically illustrate a vehicle  560  comprising a further embodiment of the present invention. The vehicle  560  includes a body  562  supported by an underlying tie structure  564  which may be in the form of a generally rectangular structure having longitudinal side members  566  and transverse end members  568 . The body  562  may be supported above the tie structure  564  by A-arm assemblies  570  having base portion  572  pivotally mounted on the tie structure and angled so that a line extending perpendicularly to the base portion and through the apex  576  of the arm assemblies will intersect at the pitch center  574  and roll center  575  of the vehicle, which may be at different elevations, but both of which are above the center of gravity  580  of the vehicle. The apex  576  of the arm assemblies may be coupled to the body  562  about transverse axis  578  in a manner similar to the connection of the A-arm assembly  302  to body  52 C, shown in  FIG. 12 . In this manner the intersection of axis  578  from the forward and rearward A-arm assemblies  570  intersect at the roll center  580  of the vehicle. As will be appreciated, the A-arm assemblies  570  may be constructed similarly to A-arm assemblies  302  described above. 
         [0206]    The body  562  is also supported by forward and rearward sliding pillars  582  and  584  extending upwardly from hub assemblies of forward wheel assemblies  586  and rearward hub assemblies of rear wheel assemblies  588 . The sliding pillars may include integral springs (not shown) to allow relative upright motion between the wheel hub assemblies and the body, in a well-known manner. 
         [0207]    The tie structure  564  is adapted to move longitudinally and transversely relative to the wheel assemblies. At the rear of the vehicle a sliding axle assembly  589  allows transverse movement between the rear portion of the tie structure and the rear wheel assemblies  588 . The axle assembly  589  includes a central tube structure  590  for receiving telescoping axle stub shafts  592  therein. Springs or other means may be used to restrict the relative movement between the axle stub shafts  592  and the tube structure  590 . The outward end portions of the axle stub shafts are connected to the rear wheel hub assemblies of wheel assemblies  588 . Longitudinal slide assemblies  594  allow for relative longitudinal motion between the tie structure  564  and the rear axle assembly  589 . In this regard, the longitudinal slide assemblies include an outer tubular member  596  supported by the tie structure transverse end member  568  for receiving a slide shaft  598  extending transversely from the tube structure  590 . Again, springs or other means may be utilized to limit the relative movement between the slide shaft  598  and its corresponding tube  596 . 
         [0208]    The structure at the forward end of the vehicle  560  is similar to that just described with respect to the rear end of the vehicle. In this regard, transverse slide assemblies  600  extend transversely outwardly from a king pin  601  mounted on a central forward subframe assembly  602  that extends forwardly from tie structure transverse member  568 . The outward end of the slide assembly  600  is coupled to a lower portion of sliding pillar  582 . 
         [0209]    Generally longitudinally directed slide assembly  604  extends forwardly from a king pin  606  mounted at the corner portions of the tie structure  568  to also couple with the lower portion of sliding pillar  582 . The king pins  601  and  606  allow the slide assemblies  600  and  604  to pivot about a vertical axis, but restrain the slide assemblies to move in a vertical direction. 
         [0210]    The slide assemblies  600  and  604  may be actively controlled to allow relative longitudinal and transverse motion between the forward end of the tie structure and the forward wheel assemblies  586  and to control the nominal orientation of the front wheels  586 . In this regard, the slide assemblies may be in the form of hydraulic linear actuators or electrical linear actuators or similar structures. Also, sensors  606  may be used to sense the orientation of the wheels  586  so as to maintain the desired alignment of the wheels. Such sensors are known in the art. 
         [0211]      FIGS. 32 and 33  illustrate vehicle  700 , wherein the hub carrier  704  serves as an interconnection between the body  702  and the tie structure  706 . This interconnection is accomplished by utilizing a slide rod or pillar  708  that is fixed to hub carrier  704  in an upright orientation. The tie structure  706  is coupled to a slide collar  710  that closely engages over the slide pillar  708  through the use of a pivot joint or similar means  712  to allow relative angular movement between the tie structure and the collar  710 . A relatively stiff lower spring  714  is interposed between the bottom of the slide collar  710  and a stop  716  affixed to the lower end of the slide pillar  708 . 
         [0212]    A body  702  is connected to an upper slide collar  718  that closely and slidably engages over the upper portion of the slide pillar  708  through the use of a ball joint  720  or similar means, thereby to enable the body to pivot relative to the slide collar springs  722 , that are relatively softer than springs  714  and are interposed between the underside of the upper slide collars  718  and the hub carrier  704  to provide spring suspension for the body. 
         [0213]    In addition, swing arms  724  may be interposed between the tie structure  706  and the body  702  to restrict longitudinal relative movement between the body and the tie structure, as well as carrying part of the weight of the body on the tie structure in a manner similar to several of the embodiments of the present invention described above. It will be appreciated that the interconnection of lines extending upwardly from the diagonal swing arms define the roll center  726  of the body which is elevationally above the center of gravity  728  of the vehicle. As such, in the manner of the other vehicles described above, during cornering body  702  will tilt inwardly toward the center of curvature of the curve rather than outwardly in the manner of a traditional vehicle. It is to be understood that the swing arms  724  may be replaced with alternative structures, for example A-arms. 
         [0214]    The vehicle  700  may include a steering system composed of rack and pinion assembly  730  having a tie rod  732  extending outwardly therefrom which is coupled to a steering arm  734  extending transversely from the upper end of slide pillar  708 , see  FIG. 33 . As will be appreciated, as the steering rod  732  is moved in the direction of arrow  736 , the hub carrier  704  and its associated wheel assembly  740  are caused to turn about slide pillar  708 . 
         [0215]    It will be appreciated that the slide pillar  708 , slide structure  710 , ball joint  712 , spring  714 , spring  722 , ball joint  720 , upper slide collar  718 , and other related components might be reduced in size so as to be able to fit within a diameter of the rim of a wheel  740 . In addition to other advantages, this would reduce the bending load that hub carrier  740  would have to carry. However, such structure may limit the amount of travel of springs  714  and  722 . 
         [0216]    Another advantage of this embodiment is the achievement of positive dynamic camber. See the discussion above regarding  FIGS. 20-23 . Positive dynamic camber is achieved because during cornering the tie structure  706  tilts outwardly relative to the curve while the body  702  tilts inwardly into the curve to a greater extent than the outward tilt of the tie structure. As a result of such tilting of the tie structure and body, and the interconnection of the body and side rod at ball joint  720  above the roll center, the side rods tilt inwardly into the curve while providing positive dynamic camber. As explained above, this improves the traction of the vehicle during turning and cornering. 
         [0217]      FIG. 34  illustrates another vehicle  742  that utilizes another sliding pillar arrangement. The sliding pillar  744  may be integrally constructed with hub carrier  746  to which the vehicle wheel  748  is attached. The vehicle body  750  is supported in part by the lower A-arm assembly  752  that is coupled to a slide collar  754  that closely engages a lower portion of the pillar  744  through the use of a pivot joint  756  or similar means to allow relative angular movement between the A-arm  752  and the collar  754 . Relatively stiff spring  758  is interposed between the bottom of slide collar  754  and a stop  760  affixed to the lower end of the slide pillar  744 . The opposite ends of the A-arm assembly  752  are coupled to the lower portion of body  750  at pivot joints  762  and  764  which allow relative angular movement between the A-arm assembly and the body. 
         [0218]    The upper portion of body  750  is supported by springs  766  that are relatively softer than springs  758 . Such springs engage over the upper portion of sliding pillar  744 , with a lower end of the springs supported by a collar stop  768  engaged over a sliding pillar  744 . The upper end of the softer upper spring  766  presses against the underside of the horizontal arm  770  that extends horizontally outwardly, and is rigidly attached to body  750 . A diagonal brace  772  extends upwardly and inwardly from an outer, distal portion of arm  770  to intersect with body  750 . The outer end of arm  770  may be attached to a slide collar  774  which allows relative angular motion between the distal end of the arm  770  and the sliding pillar  744 . In this instance, the softer spring  766  bears upwardly against the underside of the slide collar  774 . 
         [0219]    Upright control members  776  may be interposed between the wheel hub carrier  746  and arm  770 . Such control members may be in the form of control springs of the type used in other embodiments of the present invention, as described above. 
         [0220]    It is to be understood that the hub carrier  746  may be incorporated into a driven axle to drive the vehicle wheels  748 . Such drive may be accomplished through hydraulic motors incorporated into the hub carriers or through torque shafts extending through the hub carriers in a manner well known, for example as utilized in the front wheels of a four-wheel drive vehicle. 
         [0221]    In addition, it is to be understood that vehicle  742  is capable of providing the same advantages as provided by the vehicle  700  as described above, including tilting the body  750  inwardly when negotiating a curve, or pitching the body rearwardly when braking. In this regard, as with other embodiments of the present invention, the A-arm assembly  752  can be oriented so that the pitch center of the vehicle as defined by the A-arm assemblies may be at an elevation that is different from the roll center of the vehicle. Also, the A-arm assemblies can be mounted on the vehicle to be adjustable in orientation and position so as to be able to change the location of the pitch and/or roll centers during vehicle operation. Moreover, the present invention as shown in  FIG. 34  also provides positive dynamic camber to the wheels  748 . 
         [0222]      FIGS. 35 and 36  depict a further sliding pillar system used in conjunction with vehicle  780 . As shown in the figures, a double sliding pillar is utilized with each of the vehicle wheels  782 . The vehicle  780  includes a hub assembly  784  having a wheel hub section  786  and a slider frame section composed of upper diagonal arms  788  that extend upwardly and diagonally outwardly from the central hub section  786 . The slider frame section also includes relatively shorter lower arms  790  that extend diagonally downwardly and outwardly from the hub section  786 . The distal ends of each of the arms  788  and  790  are in the form of a horizontal pad or boss  791  for supporting the upright pillars  792 . The lower ends of the pillars  792  may rest on the upper portion of the corresponding pads  791  of the arms  790 , whereas upright clearance openings  794  may be formed in the pads  791  of the arms  788  for reception of the pillars  792  therethrough. 
         [0223]    The tie structure  796  may be coupled to the pillars  792  in a manner similar to that utilized in the embodiments of the present invention shown in  FIGS. 32 and 33 . In this regard, relatively stiff lower springs  798  may be interposed between the underside of slide collars  800  of the tie structure  796  and the upper side of the pads  791  of the lower arms  790 . Likewise, the body  802  of vehicle  780  may be coupled to the pillars  792  in a manner similar to that employed with the embodiment of the present invention shown in  FIGS. 32 and 33 . In this regard, upper, relatively softer springs  804  are disposed between the underside of body slide collars  806  and the upper surface of the upper pads  791  located at the distal ends of the upper arms  788 . 
         [0224]    Continuing to refer to  FIGS. 35 and 36 , the hub assembly  784  is specially designed to be used in conjunction with drive axle  807  connected to wheel drive shaft  808  through the use of universal joint  809 . Spaced apart bearings  810  are disposed between the drive axle  808  and the inside diameter of hub section  786  to anti-frictionally support the drive axle in a manner well known in the art. 
         [0225]    As will be appreciated, the embodiment of the present invention shown in  FIGS. 35 and 36  provide the same advantages as provided in the embodiments shown in  FIGS. 32 ,  33  and  34 , including the inward tilt of body  802  and outward tilt of tie structure  796  during cornering as well as the rearward tilt of body  802  and the forward tilt of tie structure  796  during hard braking. The present embodiment also provides positive dynamic camber to the wheels  782  in a manner similar to that described above. 
         [0226]      FIG. 37  illustrates a front elevational view of a vehicle  811  in a further embodiment of the present invention, wherein vehicle  811  includes two roller cams  812  rotatably mounted on the outer ends of an axle shaft  814  extending transversely outwardly from a connector bracket  815  located along the sides at the forward and rearward end portions of body  816 . The roller cams  812  ride within arcuate cam grooves  817  formed in the longitudinal tie structure  818 L extending along the left-hand side of body  816 , shown in  FIG. 37 . Although not shown, a right-hand tie structure  818  extends along the right-hand side of the body  816 . 
         [0227]    A longitudinal cam roller  820  is mounted on the outer end portion of the stub shaft  822  that extends longitudinally from the connector bracket  815 , to engage within a close-fitting follower slot  824  formed in body  816 . A connector bracket (not shown) similar to bracket  815 , shown in  FIG. 37 , is disposed on the laterally opposite side of the body at the front and rear of the body so that a connector structure is positioned adjacent each corner of the body. As such, when negotiating a corner, the centrifugal force acting through the center of gravity  826  of the vehicle  811  will cause the body to tilt inwardly toward the center of the curve, and in doing so, cam rollers  820  will roll along respective cam follower slots  824 . Likewise, during braking, the deceleration force pushing against the rear of the body will cause the body to pitch by relative movement of the cam rollers  812  along the cam slots  817  formed in the tie structure  818 , tending to lower the rear end of the vehicle and raise the upper end of the vehicle so that a high level of load is retained on the vehicle rear wheels. 
         [0228]    It will be appreciated that rather than incorporate the cam follower slot  817  in the tie structure  818 , such slot could be incorporated into a wheel hub carrier. Alternatively, the cam roller  812  and axle shaft  814  could extend laterally inwardly from a hub carrier to engage with a cam roller slot formed in the connector bracket  815 . 
         [0229]      FIG. 38  illustrates a further embodiment of the present invention wherein a vehicle  880  utilizes roller cams to allow the vehicle body  882  to roll relative to an underlying tie structure  884  when a side force is applied to the vehicle, for example, during cornering. As in other embodiments of the present invention, the tie structure  884  is carried by wheel assemblies  886  through the use of arm assemblies  888 . The arm assemblies may be resisted by a relatively torsion bar or linear resistor in a manner described herein. Also, the body  882  may be supported by softer control springs  890  which are mounted on the wheel assemblies  886 . The upper ends of the control springs  890  may be coupled to an overhead portion of the body  882 . 
         [0230]    An arcuate cam slot  892  is formed in brackets  894  located at the rearward and forward ends of the tie structure along the sides thereof. The cam slots are sized to receive cam rollers  896  mounted on the body by any convenient means, for example, utilizing stub shafts or axles (not shown). The cam slots  892  and cam rollers  896  are positioned along a circle path  898  so that the cam rollers will smoothly roll within the cam slots without binding up. It will be appreciated that the center of the circle path  898  coincides with the roll center  900  of the body  882 . Because the center of gravity  902  of the vehicle is below the roll center, when the vehicle negotiates a corner, the centrifugal force imposed on a vehicle will act through the center of gravity, thereby tending to pivot the body about the roll center. As a consequence, the body will tilt toward the inside of the corner rather than towards the outside as in a typical vehicle. Moreover, as in other vehicles described above, the tie structure will tilt somewhat toward the outside of the corner (though not to the extent that the body tilts to the inside of the corner) thereby causing the roll center to also move somewhat in an outward direction and preventing the vehicle from jacking about the roll center. 
         [0231]    It will be appreciated that the embodiment of the present invention shown in  FIG. 38  can be altered to allow the vehicle to pitch instead of roll by changing the orientation of the cam slots and cam rollers 90° from that shown in  FIG. 38  so that the axis of the cam rollers  896  is transverse to the length of the vehicle  880  rather than longitudinally of the length of the vehicle as shown in  FIG. 38 . As a further aspect of the present invention, the brackets  894  can be constructed to be adjustable relative to the tie structure  884  to alter the radius of the circle path  898 . As a consequence, the extent to which the body  882  rolls relative to the tie structure per level of force imposed on the vehicle can be varied as desired. In addition, the structure of  FIG. 37  can be incorporated into the vehicle  880  to enable the body  882  to both pitch and roll. 
         [0232]    A further embodiment of the present invention is shown in  FIG. 39 , wherein a vehicle  830  includes a body  832  supported relative to a tie structure  834  which in turn is supported by wheel assemblies  836 . The tie structure  834  may be of a rectangular box-type construction similar to those tie structures shown in  FIGS. 4 ,  5 ,  7 ,  10  and  13 . The tie structure  834  may be connected to hub assemblies  838  in a well-known manner, including in a solid axle arrangement if desired. Spring/shock absorber assemblies  840  extend diagonally, upwardly, and inwardly from the tie structure  834  to interconnect with the body  832 . Ball joints may be utilized at the upper and lower ends of the spring/shock absorber assemblies  840  in a well-known manner. 
         [0233]    A horizontal fluid strut  842  is interconnected between the tie structure and the body at an elevation corresponding to the roll center  844  of the vehicle which is at an elevation above the center of gravity  846  of the vehicle. The strut  842  is relatively stiff compared to the stiffness of the spring/shock absorbers  840 . As such, during cornering the body  832  tilts inwardly into the curve being negotiated by the compression of the inside spring/shock absorber  840  and the extension of the outside spring/shock absorber  840 . Simultaneously, the body  832  shifts somewhat laterally outwardly against the push/pull fluid strut  842 . As a result, the rate of force transfer from the body to the tie structure is lower than in a conventional vehicle, leading to many of the same advantages as discussed above, even though, due to the horizontal orientation of the push/pull fluid strut, the roll reaction center of the vehicles is at a higher elevation than in many of the other embodiments of the present invention described herein. 
         [0234]    The fluid strut  842  may be reactive as described above, or instead may be active to cause sideways movement of the body  832  when desired. In this regard, a fluid pump may be used to deliver fluid to the strut or remove fluid therefrom, thereby to cause the body to move laterally. Such pump may be similar to that described above. In addition, a fluid reservoir may be employed to provide fluid to the strut and receive fluid from the strut. Also, by this construction, the stiffness of the strut can be varied during travel. It is to be appreciated that the fluid strut  842  can be replaced by an electrically operated linear actuator. 
         [0235]      FIG. 40  illustrates a further embodiment of the present invention, wherein vehicle  850  is constructed somewhat similarly to vehicle  830 , shown in  FIG. 39 . However, in vehicle  850 , the body is supported by leading arms  852  extending transversely outwardly from the body  854  to couple with the upper end portions of struts  856  extending upwardly from hub carriers  858  of the wheel assemblies  860 . It is to be appreciated that the arms  852  may be of various constructions that are well known in the art. Also, the arms  852  can be replaced by other means for supporting the body. The arms  852  can be designed to twist and/or bend to accommodate road bumps and other discontinuities, thus functioning as a suspension member. 
         [0236]    Vehicle  850  includes a tie structure  862  connected to the hub carriers  858  by ball joints  864  or similar connection members. An A-frame structure  866  may extend upwardly from the tie structure to the elevation of the roll center  868  of the vehicle which is substantially above the elevation of the center of gravity  870  of the vehicle. The upper apex of the A-frame  866  may serve as a connection point for a transverse fluid strut assembly  872  which may be similar in construction to strut  842 , shown in  FIG. 39 . The opposite end of the strut assembly  872  may be coupled to the body  854 . It will be appreciated that vehicle  850  is capable of operating in a manner similar to vehicle  830  described above, including providing positive dynamic wheel camber. In this regard, ideally the strut assembly  872  is relatively stiff in comparison to the arms  852 , thereby to limit the sideways movement of the body when cornering. Also, various types of strut assemblies can be used. 
         [0237]      FIG. 41  illustrates a further embodiment of the present invention that is similar to the vehicle  850  shown in  FIG. 40 . Thus, the components of the vehicle  874  shown in  FIG. 41  that are the same or similar to that shown in  FIG. 40  are identified with the same part number but with the addition of a prime (′) symbol. The main difference between the vehicles shown in  FIGS. 40 and 41  is that vehicle  874  utilizes torsion bars  876  and  878  that extend from the inward ends of leading arms  852 ′ across the body  854 ′, to be anchored at the opposite side of the body. Thus, the torsion bars  876  and  878  are used to accommodate relative movement between the tie structure  862 ′ and the body  854 ′ caused by road bumps or other road discontinuities. This function does not have to be borne by the leading arms  852 ′ in the manner of the vehicle  850  shown in  FIG. 40 . 
         [0238]      FIGS. 42 and 43  illustrate a further embodiment of the present invention, wherein a vehicle  1050  includes a body portion  1052  supported by a pair of forward wheel assemblies  1054  and a pair of rearward wheel assemblies  1056 . Referring initially to  FIG. 42 , the rear wheel assembly  1056  includes a drive axle  1058  that may be powered by an engine (not shown) in a well-known manner. The outward ends of the drive axle  1058  are held captive within an upright slide retainer  1060 , of a rear slide assembly  1061 , which serves the function of a tie structure as described in other embodiments of the present invention. The axle  1058  is vertically “centered” in the slide retainer by upper and lower compression springs  1062  and  1064 , which also react against upper and lower portions of the slide retainer  1060 . Each of the laterally spaced apart slide retainers  1060  are coupled to the rear portion of body  1052  by upper and lower links  1066  and  1068  which are pinned to the upper and lower end portions of the slide retainer, respectively, and also pinned to vertically spaced apart locations on the rear portion of the body  1052 . A crank arm  1070  is fixed to the forward end portion of upper link  1066  so as to pivot about connection point  1072  of the upper link as the upper link  1066  pivots about such connection point. The distal end of the crank arm  1070  is pinned to the free end of shock absorber assembly  1074 , which is positioned generally perpendicularly to the length of the crank arm  1070 . The spring/shock absorber  1074  acts as a body spring for the vehicle  1050 . In this regard, when the rear wheel assembly  1056  rises relative to the rear portion of the body  1052 , the spring/shock absorber assembly  1074  is forced to compress so as to react against such relative movement. 
         [0239]    At the forward end of the vehicle  1050 , a forward slide assembly  1076  is utilized, which may be similar in construction and operation to the rear slide assembly  1061 . Thus, the operation of the forward slide assembly  1076  will not be repeated here. One difference between the forward slide assembly  1076  and the rear slide assembly  1061  is that a body spring/shock absorber assembly similar to  1074  at the rear of the vehicle may not be used at the forward end of the vehicle. A torsion assembly (not shown) may be employed with one or both of the forward links  1078  and  1080 . 
         [0240]    It will be appreciated that the forward links  1078  and  1080  in the rearward direction are aligned to intersect with the pitch center  1082  of the vehicle. The same is true for the rearward links  1066  and  1068 . It will also be appreciated that the pitch center  1082  of the vehicle is located at an elevation higher than the location of the center of gravity  1084  of the vehicle. 
         [0241]    In use, when the vehicle  1050  is accelerated, a rearward force acts to the center of gravity  1084  tending to raise the rear of the vehicle since the center of gravity is below the pitch center of the vehicle. Simultaneously the pitching couple acts through the body pitch center, causing the links  1066  and  1068  to transfer the pitching couple to the ground through the rear wheel assemblies  1056 . This places a downward load on the upper link  1066  and on the lower link  1068 , thereby causing the rear slide assembly to move somewhat downwardly, thereby to apply downward load on the rear axle  1058  which in turn increases the load on the rear wheel assemblies for better traction. Also during the downward movement of the rear slide assembly, the body moves downwardly somewhat so that the pitch center does not serve as the pitch reaction center, thereby lessening the rearward pitching of the vehicle during this time period. It will be appreciated that during braking, the forces act instead on the front of the vehicle  1050  in a like manner. 
         [0242]      FIG. 44  illustrates a vehicle  1090  that also utilizes the dynamic forces acting on the vehicle, and the corresponding movement of suspension arms, to reduce or increase the load imposed on the vehicle&#39;s support wheels  1092  and  1094 , with the magnitude of the load reduction or increase depending on the magnitude of the dynamic loads imposed on the body and the lengths of the suspension arms. The body  1096  of the vehicle is supported by body spring  1110  at each wheel assembly  1092  and  1094 . 
         [0243]    The vehicle  1090  includes tie structure  1098 , which may be of a box-type construction in a manner described in conjunction with several of the embodiments discussed above. In this regard, the tie structure may include lower and upper side beams  1104  and  1106  that are vertically interconnected by corner posts  1108 . The tie structure may also utilize lower and upper transverse members  1110  and  1112  that transversely interconnect the forward and rearward ends of the side beams  1104  and  1106 . 
         [0244]    The corners of the tie structure may be carried by the wheel assemblies  1092  and  1094  by use of crank arms  1114 , having a generally horizontal arm  1116  and an upright arm  1118 . At the intersection  1119  of arms  1116  and  1118 , the crank arm  1114  is pinned to the tie structure. The free end of the horizontal arm may be connected to the wheel hub assembly  1117 . The opposite end of the arm  1116  is rigidly connected to the lower end of upright arm  1118  that extends nominally upwardly from the arm  1116 . The upper end of the arm  1118  is pivotally connected to the distal end of a cylinder rod  1120 , with the inward end of the rod connected to a piston  1122  that slidably engages within a hydraulic cylinder  1124 . A spring  1125  may be positioned between the piston  1122  and the end of the cylinder  1124  to nominally position the piston within the cylinder, for example when the vehicle is stationary. The hydraulic cylinder  1124  is in hydraulic fluid connection with an upright cylinder  1126  through hydraulic lines  1128  and  1130 . The lower end of the hydraulic cylinder  1126  is fixedly attached to the structure upper side beam  1106 . The upright hydraulic cylinder  1126  includes a piston  1132  connected to the lower end of a piston rod  1134 , with the upper distal end of the rod coupled to a connecting collar  1136 , which engages over a stub shaft  1138  extending forwardly and rearwardly from the body  1096 . The coupling collar may be replaced with a U-joint assembly. 
         [0245]    The dynamic reactive system for interconnecting the body  1096  with the wheel assemblies  1117  in  FIG. 44  operates in a manner similar to the other embodiments of the present invention described herein. In this regard, when one end of the body  1096  pitches downwardly, it causes the corresponding piston  1132  to extend downwardly, in turn forcing hydraulic fluid from the bottom side of cylinder  1126  to the end of cylinder  1124  opposite rod  1120 , forcing the rod outwardly relative to the cylinder which in turn causes counterclockwise rotation of crank arm  1114 , tending to apply a downward force on wheel  1092 , whereby causing the adjacent end portion of the tie structure to raise somewhat upwardly. At the other end of the vehicle  1090 , the reactive interconnecting force acts oppositely so that hydraulic fluid is forced from cylinder  1126  through line  1128  to the side of piston  1122  corresponding to piston rod  1120 . As such, when applying a strong braking force on vehicle  1090 , significant load is maintained on the rear wheels of the vehicle to assist in maintaining control of the vehicle rather than skidding or sliding sideways. 
         [0246]    The diameter of cylinder  1124  may be larger than the diameter of cylinder  1126  so that the amount of the body roll and/or pitch is more than the amount of wheel movement relative to the tie structure. Also, rather than being passive as described above, the cylinders  1124  and  1126  can be powered to provide an active suspension system for the vehicle  1090 . A fluid pump, as described above can be utilized in this regard. If such an active suspension system is utilized, then the post  1100 , described above, may be eliminated. 
         [0247]    As a further matter, a torsion bar (not shown) can be utilized in conjunction with crank arms  1114  to nominally position the crank arms and also modulate the pivoting movement of the crank arms about pivot point  1119 . 
         [0248]      FIG. 45  illustrates a further embodiment of the present invention incorporated into a semi tractor trailer  1150 . The vehicle  1150  includes a tractor  1152  composed of a cab  1154  mounted on a tractor frame  1156  which also serves as a tie structure of the tractor. The tractor may be supported by conventional front steerable wheels  1158  and rear drive wheels  1160 . 
         [0249]    The cab  1154  may be supported on the tie structure  1156  by four diagonally disposed links  1162  which may be connected at their upper and lower ends to the cab and tie structure, respectively, by pivot joints, ball joints, universal joints or other types of joints. The links  1162  may be oriented so that if extended in the upper direction the links would intersect at a common point, which common point corresponds to the roll center and pitch center  1164  of the body. As illustrated in  FIG. 37 , the roll/pitch center  1164  is at an elevation above the center of gravity  1166  of the tractor. 
         [0250]    The cab  1154  is also supported by adjustable front control members  1168  supported by a front wheel hub assembly  1169  and rear control members  1170 , which are supported by an axle frame assembly  1171  which in turn is carried by axle members  1172 . In addition, the tie structure  1156  is supported on the front hub assembly by relatively stiff, but adjustable, air shocks or pillows  1174 , whereas the rear portion of the tie structure  1156  is supported on the rear of assembly  1173  by comparable air shocks or pillows  1175 . 
         [0251]    A fifth wheel assembly  1173  includes a base portion  1176  that is directly supported by relatively stiff adjustable spring/slider control members  1177  as well as by relatively soft linear control members  1178 . A standard plate portion  1179  is supported by the base portion  1176 . The spring/slider control members extend upwardly from the tractor tie structure to be pivotally coupled to the underside of the fifth wheel base portion near the fore and aft center thereof. As shown in  FIG. 45 , two control members  1177  may be utilized in laterally spaced-apart relationship to each other. Of course, other arrangements of the control members may be utilized. A plurality of linear control members  1178  may be utilized, as shown in  FIGS. 45 ,  46  and  47 , perhaps one at every quadrant of the fifth wheel base  1176 . 
         [0252]    As in other embodiments of the present invention described above, by the foregoing construction, when the tractor  1152  rounds a corner the centrifugal force acts on the body at the center of gravity  1166 , which is below the elevation of the roll center  1164 , so that the body will tilt inwardly into the corner rather than outwardly as in a typical vehicle. Correspondingly, when quickly braking, the longitudinal force acts on the tractor at the center of gravity, which is at an elevation below the pitch center  1164 , thereby tending to cause the rearward portion of the cab to impose a downward force on the tie structure, thereby to maintain significant load on the rear tractor wheels  1160 . 
         [0253]    During cornering, the tie structure  1156  is allowed to tilt outwardly of the curve somewhat, but not to the extent that the cab tilts inwardly. During this outward tilt of the tie structure, the roll center is shifting, so it does not serve as the reaction center of the tractor, thereby reducing the jacking effect imposed on the tractor then cornering. Likewise, during hard braking, the tie structure tilts somewhat in the forward direction, but not nearly to the extent that the cab  1154  tilts in the rearward direction. During this tilting motion of the tie structure/tractor frame  1156 , the pitch center  1164  is shifting so as to reduce the rate of force transfer through the tractor  1152 , thereby reducing the pitch jacking effect imposed on the vehicle. The combined result of the rearward tilting of the cab  1154  and the somewhat forward tilting of the tie structure/tractor frame  1156  during hard braking allows for a significant load to be maintained on the rear wheels  1160  without imposing a high pitching effect on the tractor. This can result in quicker and safer braking of the tractor  1152 . 
         [0254]    The semi trailer  1150  includes a trailer portion  1180  that is constructed to function similarly to the tractor  1152 . In this regard, trailer  1180  includes a load platform  1182  that is supported above a rear wheel assembly  1184 . As shown in  FIG. 45 , a variable resistance, relatively soft control member  1186  that is supported by a subframe  1188  carried by the rear hub assembly  1190  of the semi trailer  1180 . Lateral stability between the trailer bed  1182  and wheel hubs  1190  is achieved by struts  1189  extending forwardly from subframe  1188  to complete the lower end of a brace  1191  that extends downwardly from the bed  1182 . 
         [0255]    As in the linear control members  1178  used in conjunction with the tractor and fifth wheel described above, the linear control members  1186  are designed to accommodate relative linear, transfers, rolling and pitching movement between the load platform  1182  and the wheel hub assembly  1190 . The rear end of the trailer frame/tie structure  1184  is supported on the hub assembly  1190  by a relatively stiff spring slider assembly  1192  that extends diagonally upwardly and forwardly from a base plate  1193  which in turn is supported above the hub assembly by an air shock  1194 , which may be similar to air shocks  1174  and  1175  of the tractor  1152 . The relatively stiff spring/slider assemblies  1177  and  1192  are angled upwardly and diagonally rearwardly and forwardly, respectively, so that lines extending colinearly of the length of such members would intersect at the pitch center  1196  of the trailer  1196  which is above the center of gravity of the trailer  1198 . It will be appreciated that by the foregoing construction, the trailer  1180 , with a load thereon, would function in a manner very similar to the cab  1152  during cornering as well as during braking and accelerating. As a result, a much more stable semi-tractor trailer is achieved than the standard semi-tractor trailers currently being utilized. 
         [0256]    Semi trailer  1150  is illustrated and described as having a tractor with a tandem rear axle. However, the present invention could readily be incorporated with a tractor having a single rear axle. In that situation the fifth wheel assembly  1173  would be supported by a single rear axle. Such semi tractor with a single rear axle would nonetheless function in substantially the same manner as tractor  1152  described above. 
         [0257]    It will also be appreciated that the present invention as shown in  FIGS. 45-47  can be incorporated into other types of vehicles, such as rail cars, especially the structure of the fifth wheel assembly  1173  and the trailer portion  1180 . 
         [0258]      FIG. 48  illustrates the present invention as incorporated into a motorcycle type vehicle  1201 . The motorcycle includes a tie structure  1202  that supports a body structure  1204  designed with a seat  1206 . The body structure is supported on the tie structure by forward and rearward link pairs  1208  and  1210 , on each side of the forward and rearward end portions of the tie structure. An extension of links  1208  and  1210  in the upward direction would result in their intersection at the pitch center  1212  of the motorcycle, which is substantially above the center of gravity  1214  of the cycle. The links  1208  and  1210  may be coupled to the tie structure and the body by use of pivot connections in a manner well known. 
         [0259]    The body  1204  is also supported and stabilized relative to forward and rearward wheels  1216  and  1218  by forward and rearward relatively soft springs  1220  and  1222 . Such springs are connected between the forward and rearward wheel hubs and the body in a well-known manner. Body stops (not shown) can be incorporated into the springs to limit the pitch of the body relative to the tie structure. Also, springs  1220  and  1222  can be of other construction, as is known in the art. 
         [0260]    The tie structure  1202  is coupled to the forward fork assembly  1224  by a forward connection arm assembly  1226  and is connected to the hub section of the rear wheel  1218  by a rearward connector arm assembly  1228 . A transverse forward torsion bar  1230  is interposed between the rearward portion of the forward connection assembly  1226  and the tie structure  1202 , whereas a transverse rearward torsion bar  1232  or other type of spring arrangement is interposed between the forward end of the rearward connector arm assembly  1228  and the adjacent portion of the tie structure. The forward and rearward torsion bars  1230  and  1232  are relatively stiff in comparison to the body springs  1220  and  1222 . Also, other types of structures can be used in place of torsion bars  1230  and  1232 , for example, a crank arm and linear control member as described herein. Also, a dampener can be used in conjunction with connection arm assemblies  1226  and  1228 ; for example, a dampener similar to that dampener  95  shown in  FIG. 1 . 
         [0261]    The motor  1234  of the motorcycle  1201  may be mounted within and supported by the tie structure  1202 . The motor can be coupled to the rear wheel  1218  of the cycle in a manner well known in the art. Alternatively, an electric motor may be incorporated into the rear and/or front wheel hubs to power the motorcycle. The battery therefor can be carried by the tie structure, for example, at the location of the engine  1234 . 
         [0262]    In operation when accelerating or braking, a longitudinal force is imposed on the cycle  1201  through the center of gravity  1214  which is at an elevation well below the pitch center of the vehicle. As such, the body  1204  will tend to tilt forwardly during acceleration and tilt rearwardly during hard deceleration, thereby retaining a significant load on the front wheel  1216  during acceleration and a significant load on the rear wheel  1218  during braking. This is opposite to the typical situation in a motorcycle. 
         [0263]    Also during braking, the torsion bars  1230  and  1232  allow the tie structure to tilt downwardly somewhat in the forward direction. Due to the torsion bars  1230  being stiffer than spring  1220 , the tie structure may be able to continue moving during braking after the shifting of the body has ceased. As a consequence during this tilting motion, the pitch center  1212  is shifting, thus reducing the rate of force transfer through the cycle during braking, thereby reducing the tendency of the cycle to pivot about its pitch reaction center. Conversely, during hard acceleration, the torsion bars  1230  and  1232  allow the tie structure to tilt somewhat downwardly in a rearward direction. As a consequence, the pitch center  1212  does not serve as the pitch reaction center of the cycle. As will be appreciated, through the construction of the present invention, the cycle  1201  is capable of braking and accelerating in a relatively safe manner, especially in comparison with standard, typical motorcycles. 
         [0264]      FIG. 49  illustrates a further embodiment of a motorcycle  1240  constructed in accordance with the present invention. The motorcycle  1240  is constructed similarly to motorcycle  1201 . As such, the corresponding components of motorcycle  1240  are given the same part numbers as in motorcycle  1201  but with the addition of an “A” suffix. Construction function motorcycle  1240  that is the same or similar to motorcycle  1201  will not be repeated here. 
         [0265]    One difference between motorcycle  1240  and motorcycle  1201  is that in motorcycle  1240  the engine  1234 A actually functions as a part of the tie structure  1202 A. In this regard, the rear links  1210 A and rear connect arm assembly  1228 A are mounted to the rear portion of the engine  1234 A. Having the engine  1234 A function as part of the tie structure  1202 A reduces the complexity and weight of the motorcycle  1240 . 
         [0266]    As another feature of the present invention, the seat  1206 A is located at an elevation below the top of the front and rear wheels  1216 A and  1218 A. This allows a relatively low overall center of gravity for the motorcycle and rider relative to motorcycles in which the rider sits higher relative to the wheels. 
         [0267]      FIGS. 50 and 51  illustrate the present invention being incorporated into a railway car  1250 . The railway car includes a body  1252  supported above a tie structure  1260  by corner links  1256  that extend diagonally, inwardly at the front of the tie structure and diagonally, inwardly at the rear of the tie structure. The upper ends of the links  1256  may be coupled to the body using pivot connections, ball joints, universal joints or other appropriate means. The lower ends of the corner links  1256  are coupled to mounting ears  1258  that project upwardly from tie structure  1260 , projecting forwardly and rearwardly from an axle structure  1254 . The tie structure includes a transverse torsion bar  1262  over which an elongate collar or tube  1261  engages. Bushings can be used between the inside diameter of the tube  1261  and the outside diameter of the box  1262 . Ears  1258  project upwardly from the collar. The torsion bar  1262  is coupled (for example, splined) to the outward, distal ends of arms  1264  that cantilever from the axle assembly  1254 . The inward ends of the arms  1264  are coupled to the axle assembly  1254  by ball joints or similar means to allow the arms to turn about an axis extending along the length of the arms. 
         [0268]    As most clearly shown in  FIG. 50 , the corner links  1256  may be diagonally disposed relative to the body  1252  so that if extended in their upwardly direction they would intersect at a point  1266  that functions as the roll center of the railway car. As apparent, such roll center is above the center of gravity  1268  of the railway car. 
         [0269]    The weight of the body  1252  may also be carried in part by spring/shock absorber assemblies  1270  extending upwardly from the axle assembly  1254  and coupled to an overhead portion of the body  1252 . The characteristics of the spring/shock absorber assembly  1270  can be varied as desired so as to select the relative amount of the weight of the body  1252  being carried by the spring/shock absorber assemblies. 
         [0270]    The axle assembly  1254  is carried by standard railway wheels  1272  which ride on standard railway tracks  1274 . The wheels  1272  can be replaced to fit different tracks. The wheels  1272  are mounted on wheel axles  1275 . 
         [0271]    In use, when the railway car  1250  is rounding a corner, the centrifugal force is applied thereto through the center of gravity  1268 . Because the center of gravity is located below the roll center  1266 , the body  1252  will tilt inwardly into the corner as opposed to tilting outwardly in a manner of a standard railway car. Moreover, during such tilting of the body  1252 , the tie structure tilts somewhat downwardly on the outward side of the corner, but not nearly to the extent that the body  1252  is capable of tilting. This movement of the tie structure  1260  is resisted by torsion bar  1262 . Moreover, due to the torsion bar  1262  being relatively stiffer than the spring/shock absorber assemblies  1270 , the tilt of the body will be completed before the maximum tilt of the tie structure occurs. As a result, a rate of force transfer through the railway car  1250  is lower than would occur if the tie structure had “bottomed out” before the body had “bottomed out.” As a consequence, the generation of a significant roll couple tending to roll the railway car about the outward wheels  1272  during cornering is forestalled. As such, the railway car  1250  is designed to provide some of the same advantages provided by the other vehicles described herein. 
         [0272]    A further embodiment of the present invention that is specifically designed for incorporation into a rail car  1277  is illustrated in  FIG. 52 . The illustrated rail car includes a body portion  1278  supported on an underlying tie structure/axle  1279  by relatively soft air pillow structures  1280  upon which an anchoring plate  1281  pivotally supports the underside of a load bearing column structure  1282  which is interconnected by body structural members  1283  and  1284 . An axle shaft  1285  axles the tie structure  1279  to wheels  1286  which ride on conventional rails  1287 . 
         [0273]    The body  1278  is also connected to the tie structure  1279  by diagonally disposed hydraulic sliders  1288  having their upper end pinned to body structural member  1283  and their lower end pinned to the outward end of a horizontal double piston cylinder assembly  1290  mounted on the tie structure  1279 . The outward end of the piston rods  1291  are pinned to the lower outboard ends of the hydraulic sliders  1288 . It will be appreciated that the hydraulic sliders  1288  are oriented so that lines extending colinear thereto intersect at the lateral center of the rail car at an elevation corresponding to the roll center  1292  of the rail car, which is above the center of gravity  1294  of the rail car. Moreover, by extending or contracting the cylinder rods  1290 , the vertical location of the roll center  1292  may be varied as desired, including during actual operation of the rail car. 
         [0274]    It will be appreciated that the rail car  1277  operates in a manner similar to rail car  1250  described above, whereby when the rail car  1277  is rounding a corner, that centrifugal force is applied thereto through the center of gravity  1294 . Because the center of gravity  1294  is located below the roll center  1292 , the body  1278  will tilt inwardly into the corner as opposed to tilting outwardly in the manner of a standard rail car. 
         [0275]      FIG. 53  illustrates a further embodiment of the present invention wherein vehicle  1400  employs a tie structure  1402  in the form of an upright structure adjacent each of the wheel assemblies  1404  of the vehicle. The vehicle includes a steerable hub carrier assembly  1406  integrated into the wheel assembly  1404 . The hub carrier assembly includes an upright inboard post portion  1408  which is coupled to a further inboard upright tie structure post  1402  by parallel upper and lower arms  1410  and  1412 . Also, a relatively stiff strut or spring assembly  1414  extends upwardly and diagonally inwardly from the lower end of hub carrier post  1408  to an upper portion of the tie structure  1402 , perhaps at the same location that the upper arm  1410  couples to the tie structure. Preferably the strut/spring assembly is double acting, so as to resist movement of the tie structure in both the upward and downward directions relative to the hub carrier assembly. It will be appreciated that the spring assembly  1414  supports the tie structure  1402  relative to the hub carrier assembly  1406 , and links  1416  and  1418  couple the tie structure to the adjacent portion of the vehicle body  1420 . As shown in  FIG. 53 , the inboard ends of the links  1416  and  1418  are oriented so that lines extending colinearly with the links  1416  and  1418  intersect at the roll center  1422  of the vehicle. Also, relatively softer spring assemblies  1424  extend upwardly from hub carrier post  1408  to couple with an overhead portion of the body  1420 . 
         [0276]    It will be appreciated that the present invention shown in  FIG. 53  allows the body  1420  to tilt inwardly into a curve during cornering while allowing a controlled amount of outward movement and tilt of the tie structure  1402  so that the roll center  1422  also moves outwardly, thereby preventing the vehicle from jacking about the reaction center as roll center is moving outwardly. In this regard, when cornering the centrifugal force on the vehicle  1400  acts through the center of gravity  1426  which is below the roll center  1422 , thereby causing the body  1420  to tilt inwardly into the curve. At the same time, the force being imposed on the roll center  1422  in the direction of arrow  1428  imposes compression loads on links  1416  and  1418 , which load is resisted by spring assembly  1414 . As a result, the tie structure post  1402  tends to move downwardly. This downward motion of the tie structure post allows the roll center  1422  of the vehicle to move slightly downwardly as the vehicle is cornering, thereby preventing the vehicle from jacking about the reaction center during movement thereof. As will be appreciated, the present invention as shown in  FIG. 53  provides the same advantages of other embodiments of the present invention without requiring a tie structure of a significant structure. 
         [0277]      FIG. 54  illustrates a further embodiment of the present invention, wherein a vehicle  1450  includes a hub carrier assembly  1452  which is attached to the lower end of a MacPherson strut assembly  1454 . The upper end of the strut assembly  1454  is coupled to an overhead portion of the vehicle body  1456  in a well-known manner. A drive axle (not shown) can be incorporated into the hub carrier assembly  1452  to drive the wheel assembly  1458  in a well-known manner. Also, the wheel assembly  1458  may be steerable using a steering system similar to that described with respect to  FIG. 34 , above. In this regard, an actuator assembly  1460  is connected to the upper arm  1462  of a pivot arm assembly  1464  which is pivotally mounted along the height of the MacPherson strut  1454 . The upper arm  1462  extends forwardly (out of the paper) from the upper end of the pivot arm assembly  1464  for coupling to the laterally outward end of the actuator assembly  1460 . Thus, as the actuator assembly  1460  extends and retracts, the pivot arm assembly  1464  is caused to pivot about a vertical axis. A lower arm  1468  extends forwardly (out of the paper) from the lower end of the pivot arm assembly  1464  to couple with a lateral steering arm  1470  that extends laterally from the lower arm to couple with an arm  1472  that extends forwardly (out of the paper) from steering knuckle  1474  which is integral with wheel spindle  1476 . In this way, steering is accomplished through a remote system that is actuated by this steering wheel through a hydraulic or electrical system (which is not shown but is well known in the automotive industry). It will be appreciated that other steering systems can be utilized in place of the steering system of  FIG. 54  without departing from the spirit or scope of the present invention. 
         [0278]    A relatively stiff spring slider assembly  1478  (preferably double acting) is interconnected between the lower end of the MacPherson strut assembly  1454  and an inward portion of the vehicle body  1456 . The spring/slider assembly  1478  is positioned so that a line extending colinearly therefrom passes through the roll center  1480  of the vehicle, which is located somewhat above the center of gravity  1482  of the vehicle. It will be appreciated that the spring slider assembly  1478  can be passive and thus reacting to lateral forces applied to the vehicle, or can be active so as to control the roll of the vehicle as desired. 
         [0279]    It will be appreciated that vehicle  1450  shown in  FIG. 54  provides the same advantages as vehicle  1400  shown in  FIG. 53 . In this regard, during cornering, centrifugal force imposed on the vehicle  1450  acts through the center of gravity  1482 , which is below the roll center  1480 , thereby tending to cause the body  1456  to rotate inwardly during cornering about the roll center. At the same time, the centrifugal force on the body is transmitted to the wheel assembly  1458  through the roll center  1480  and through the spring/slider assembly  1478 , thereby causing compression of the spring/slider assembly and thus allowing a certain amount of lateral and downward movement of the body  1456  toward the outside of the curve. During this lateral movement, the body roll center  1480  does not serve as the reaction center about which the vehicle would typically jack, thereby reducing the jacking effect imposed on the vehicle during cornering as in the other embodiments of the present invention. 
         [0280]      FIG. 55  shows an alternative embodiment of the spring/slider assembly  1478  of  FIG. 54 . In  FIG. 55 , the spring/slider assembly  1486  includes two spring/slider units  1488  that are in parallel relationship to each other, being separated by transverse connecting brackets  1490 . It will be appreciated that the construction of the spring/slider assembly  1486  shown in  FIG. 55  can provide increased stability of the vehicle body relative to the steering and suspension system in the fore and aft direction. In all other respects, the present invention shown in  FIG. 55  may be similar to or the same as shown in  FIG. 54 . 
         [0281]      FIG. 56  shows a further alternative embodiment of the slider/strut assembly  1478  of  FIG. 54 . In the slider/strut assembly  1492  of  FIG. 56 , the inboard end thereof is attached to an A-arm assembly  1494  which is coupled to the vehicle (not shown) at ball joints  1496  or similar joints. Also shown in  FIG. 56 , control lines  1497  and  1498  interconnect with opposite ends of the cylinder portion  1499  of the spring/slider assembly  1492  so as to provide active control for the spring/slider assembly. In this regard, the lines  1497  and  1498  may be connected to a fluid supply system (not shown). It can be appreciated that rather than being actuated by a fluid, the spring/slider assembly  1492  may be electrically controlled in a manner that is well known. It will also be appreciated that a structure shown in  FIG. 56  provides the same advantages as that shown in  FIG. 54 , and operates in substantially the same manner. The use of the A frame  1494  enables the strut/slider assembly to be connected to the body at more than one location, thereby spreading out the load on the body when force is transferred between the body and the spring/slider assembly. 
         [0282]      FIGS. 57 and 58  illustrate a further embodiment of the present invention wherein vehicle  1500  includes a body  1502  supported on a combination hub carrier and slider assembly  1504  coupled to wheel assembly  1506 . The wheel assembly  1506  may be adapted to be steered relative to the hub carrier/slider  1504  by various systems, including those described above. Pairs of upper and lower A-arms  1508  and  1510  interconnect the body  1502  to the hub carrier/slider assemblies. As shown in  FIG. 57 , the A-arms  1508  and  1510  are oriented in the diagonally upwardly and laterally inwardly direction so that lines extending therefrom that bisect the two arms of each A-arm assembly intersect at the roll center of the vehicle  1512  which is above the center of gravity of the vehicle  1514 . The laterally inward ends of the A-arm assemblies  1508  and  1510  may be coupled to the body with ball joints or other types of joints. The laterally outward ends of the A-arm assemblies  1508  and  1510  are coupled to sliders  1516  and  1518  that are constrained to slide up and down a slideway  1520  formed along the height of a post portion  1522  of the hub carrier/slider assembly. 
         [0283]    Referring to the fragmentary side elevational view shown in  FIG. 58 , the A-arm assemblies  1508  and  1510  are oriented in the fore and aft direction of the vehicle  1500  so that lines extending through the connections of the A-arm assemblies to the body intersect at the pitch center  1523  of the vehicle. As described in other embodiments of the present invention, for example, the embodiment shown in  FIGS. 10 and 11 , orienting the A-arm assemblies in this manner allows the vehicle to pitch about its pitch center during acceleration and braking, but in the opposite direction of a standard vehicle. 
         [0284]    Relatively soft springs  1524  and  1526  extend between the inward hub portion  1528  of the hub carrier/slider assembly  1524  and one or both of the arms of the A-arm assemblies  1508  and  1510 . The springs  1524  and  1526  are able to support the inward ends of the A-arm assemblies relative to the slideway  1520  while allowing the A-arm assemblies to move up and down within the slideway. A stiffer linear control unit  1530  is pivotally coupled to the inward end of the hub portion  1528  and also coupled to the body  1502 , for example at, or close to, the location that the upper A-arm assembly  1508  is coupled to the body. The control unit  1530  (preferably double acting) resists the lateral movement of the body relative to the hub carrier/slider assembly  1504 . 
         [0285]    The embodiment of the present invention shown in  FIGS. 57 and 58  functions very similarly to other embodiments of the present invention. In this regard, during cornering the centrifugal force acting on the vehicle  1500  acts through the center of gravity  1514 . The longitudinal forces acting on the vehicle during braking or accelerating also act through the center of gravity  178  of the vehicle  1514 . As such, during cornering, the body  1502  will tilt inwardly toward the center of the curve. Correspondingly during braking, the body will tend to tilt downwardly in a rearward direction and during accelerating the body will tend to tilt downwardly at the forward end of the vehicle. This is contrary to the conventional direction of vehicle body roll during cornering or vehicle body pitch during acceleration or braking. 
         [0286]    Moreover, during cornering, the centrifugal force acting on the vehicle are transmitted to the ground through the roll center  1512  through the hub carrier/slider assembly  1504  and to the wheel assemblies  1506 . As such, the adjacent portion of the body  1502  shifts somewhat downwardly and outwardly, with the sliders  1516  and  1518  sliding down slideway  1520 , causing the inward ends of the A-arms  1508  and  1510  to lower relative to the hub carrier/slider assembly  1504 . This movement of the body is resisted by the control unit  1530  which only allows a certain amount of such body movement. However, such movement is sufficient to prevent the roll center  1512  to serve as the reaction center of the vehicle, thereby reducing the jacking effect imposed on the vehicle during cornering. 
         [0287]    The same effect is achieved during braking or accelerating, wherein during braking the body  1502  tends to shift somewhat in the forward direction and during acceleration the body tends to shift somewhat in a rearward direction relative to the hub carrier/slider assembly. Thus, during such braking or accelerating the pitch center of the vehicle does not serve as the reaction center causing the body to dive during braking or squat during accelerating, as described above in other embodiments of the present invention. However, one difference in the embodiments of the present invention shown in  FIGS. 54-58  is that no tie structure per se is required in order to achieve the advantageous operating characteristics of the vehicles  1450  and  1500 . Rather, such effect is achieved by the construction and orientation of the suspension system components of these vehicles. 
         [0288]    While the preferred embodiments of the invention have been illustrated and described, it will be appreciated that various changes can be made therein without departing from the spirit and scope of the invention. Also, it is to be appreciated that the present invention may be utilized in a wide range of vehicles, including passenger vehicles, SUVs, all-terrain vehicles, racing vehicles, dragsters, motorcycles, trucks, pickups, tractors as well as rail cars. Although the present invention has been illustrated in terms of wheeled vehicles, the present invention may also be incorporated into track vehicles, for instance military personnel carriers and tanks.