Abstract:
The present invention provides an apparatus adapted to engage a surface, such as a road or racetrack. The apparatus provides an output to an operator that is representative of the current tractive condition of the surface. The indication from the measuring device may be adapted to provide a quantifiable indication to a driver or crew related to recent changes in the tractive condition of the surface. The driver or crew may in turn configure aspects of a racing vehicle, driving methodology and performance expectations based on current and measurable surface conditions.

Description:
[0001]    The present application claims the benefit of previously filed U.S. Provisional Application Ser. No. 60/779,608 filed Mar. 6, 2006 and is incorporated herein by reference. 
     
    
     TECHNICAL FIELD 
       [0002]    This invention relates generally to an apparatus adapted to indicate the tractive condition of a surface, and more particularly to an apparatus adapted to provide a quantifiable indication relative to periodic changes in the tractive condition of the surface. 
       BACKGROUND 
       [0003]    Various sports, such as sports car, motorcycle and bicycle racing, are impacted to a large degree by the condition of the track surface that is being raced on. More specifically, the ability of the tires to engage and hold the track surface continuously changes. This continuous change often creates a need to make adjustments to the tire pressure, suspension system and chassis of the car or cycle. Additionally, in some racing activities the racer is required to make a prediction related to how fast he expects to finish the race. Based upon the accuracy of the prediction, the outcome of the race may be adjusted, similar to a handicap system. 
         [0004]    Currently drivers must rely on imperfect methods of determining the condition of a racing surface. One such method utilizes a crewmember to drag his or her foot along a portion of the race surface, afterward formulating an estimation, relative to the condition of the surface. The crewmember must then communicate the results of this imprecise estimation to the driver or other crewmembers. 
         [0005]    It would be desirable to provide racers with a method of analyzing the condition of the racing surface and further provide a consistent yet quantifiable measurement related to the current condition of the racing surface. 
         [0006]    U.S. Pat. No. 5,814,718 to Andresen et al discloses a method and apparatus for controlling friction between the tires of a vehicle and a road surface. The apparatus utilizes a plurality of mathematical curves to calculate maximum friction and in turn controls the vehicle through a means to prevent slip related to braking or acceleration. This method of controlling slip is typically not permitted during sanctioned race activities. It would be desirable to provide a quantifiable and consistent method to analyze surface conditions 
         [0007]    The present invention is directed to overcoming one or more of the above identified problems. 
       SUMMARY OF THE INVENTION 
       [0008]    In one embodiment of the present invention, an apparatus is provided to engage with a surface, such as a road or a race surface. A contact portion of the apparatus is moved along the surface by a mechanical force. An indicator is adapted to display a value related to the amount of force required to move the contact portion in relation to the surface. 
         [0009]    In another embodiment of the present invention, a method of determining the condition of a racing surface is provided. The method includes the steps of applying a measuring device to the surface, moving a contact portion of the measuring device in relation to the surface and observing an indication related to the condition of the surface. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0010]      FIG. 1  is a sectional elevation view of a measuring device having a pair of contact levers biased against a surface. 
           [0011]      FIG. 2  is a sectional elevation view of the measuring device wherein the contact levers have been displaced in relation to the surface. 
           [0012]      FIG. 3  is an isometric sectional view of the present invention illustrating a contact assembly adapted to engage a surface. 
           [0013]      FIG. 4  is a hydraulic circuit adapted to actuate the measuring device and provide an indication of the condition of the surface. 
       
    
    
     DETAILED DESCRIPTION 
       [0014]    Referring to  FIG. 1 and 2 , by way of example of a measuring device  10  is shown. Measuring device  10  is adapted to indicate a tractive condition of a surface  12 , such as a road or racetrack. The measuring device  10  includes a housing  14  adapted to contain a contact assembly  15  of the measuring device  10 . The housing  14  as illustrated, is a substantially cylindrical member, although it should be understood that numerous other forms may be suitably adapted to hold the contact assembly for its intended purpose. The housing  14  includes a first end portion  16 , a second end portion  18  and a body  20  extending between the first and second end portions  16 , 18 . The body  20  is shown for example as being an annular member and includes an interior surface  22  and an exterior surface  24 . A plurality of protrusions  27  extend from the first end portion  16  in a direction away from the second end portion  18 . The protrusions  27  are adapted to prevent movement of the first end portion  16  in relation to the surface  12  when the measuring device is being actuated. The exterior surface  24  of the body  20  has a stepped outer diameter and forms a stop ring  26  extending along the exterior surface  24 . Positioned about the exterior surface  24  is a lock ring  28 . The stop ring  26  and the lock ring  28  are positioned at predetermined locations between the first end portion  16  and the second end portion  18 . The stop ring  26  and the lock ring  28  may be permanently affixed in relation to the body  20 , or adjustably attached using conventional mechanical fastening methods. A collar  30  is slideably attached about the stop ring  26  of the body  20 . The collar  30  includes a wall  32  and a top ring  34 . The wall  32  includes an interior surface  35  adapted to slide along the stop ring  26 . The top ring  34  is adapted to engage the stop ring  26  and prevent the collar  30  from disengaging the body  20 . The top ring  34  may be mechanically attached to the collar  30  for assembly purposes or alternatively machined into the collar  30 . The collar  30  includes a bottom surface  36  opposite the top ring  34 . The bottom surface  36  is substantially flat and adapted to engage the surface  12  of the road or racetrack. A preload spring  38  is disposed between the lock ring  28  and top ring  34 . The preload spring  38  acts to control the amount of force that is transmitted from the housing  14  to the contact assembly  15 , when the measuring device  10  is being biased toward the surface  12 . A lock mechanism (not shown) may be positioned in relation to the housing  14  and contact assembly  15  to prevent movement of the contact assembly  15  toward to the surface  12  during actuation of the measuring device  10 . 
         [0015]    Referring now to  FIG. 3 , a detailed view of the contact assembly  15  of the present invention is shown. At least one contact lever  40  is moveably disposed within the contact assembly  15 . As illustrated, a pair of contact levers  40  is arranged in a manner to permit movement along the surface  12 . The contact levers  40  include a contact surface  42 , positioned to engage the surface  12  being measured. As disclosed the contact surface  42  is manufactured from wear resistant material such as steel. However it may be found through to manufacture the contact surface  42  from materials such as non-ferrous, composite, or ceramic. Contact surface  42  may include a surface texture  43  such as cross hatched, shot peened, grooved, smooth or other formation positioned thereon. As disclosed the contact levers  40  additionally include a shoulder  44  and a bore  46 . The bore  46  is arranged to engage a shaft  48  and a pair of holes  50  provided in the contact assembly  15 . The shoulder  44  is adapted to be acted on by an actuator  52  causing rotation of the contact levers  40  about the shaft  48 . Rotation of the contact levers  40 , in turn causes movement of the contact surface  42  along the surface  12 . 
         [0016]    As illustrated the actuator  52  is a hydraulic actuator  56 . It should be noted that numerous types of actuators  52  may be used to engage the contact assembly  15 . Types of actuators  52  include but are not limited to, a drive screw, a pneumatic actuator and a linear motor. It should be noted that the method of actuation must be aggressively controllable, allowing a smooth and consistent application of force to the contact assembly  15 . The sudden actuation at a rate that is not properly controlled may result in a spike (higher than actual indication of traction). Additionally, the actuator must be capable of providing measurable indication of the force being applied to the contact assembly  15 . An adjustment mechanism  54  is positioned between the contact assembly  15  and the actuator  52 . The adjustment mechanism  54  acts to control the distance between the actuator  52  and shoulder  44  of the contact lever  40 . Movement of the actuator  52  in a direction toward the shoulder  44  causes the contact surface  42  to be moved along the surface  12 . 
         [0017]    Referring now to  FIG. 4 , the hydraulic actuator  56  is illustrated. The hydraulic actuator  56  includes an input piston  58  and an output piston  62  and a fluid reservoir  64  disposed within an actuator housing  64 . As disclosed, the input piston  58  is positioned between the reservoir  64  and the output piston  62 . A fluid coupling  66  is disposed between the input piston  58  and output piston  62 . A check valve  68  and a relief valve  72  are disposed in the input piston  58 . The check valve  68  may permit flow of hydraulic fluid in a direction from the reservoir  64  toward the fluid coupling  66 . The relief valve  72  may permit flow of hydraulic fluid in a direction from the fluid coupling  66  toward the reservoir  64 . The check valve  66  and the relief valve  72  are sized to permit fluid flow in each respective direction at predetermined fluid pressure. An orifice  74  is provided between the fluid coupling  66  and an indicator  76 . The indicator  76  is adapted to provide a value related to the amount of force required to move the contact surface  42  along the surface  12 . As illustrated the indicator  76  is a pressure gauge having a high pressure “hold” feature adapted to preserve the highest value indicated by the gauge. Other types of indicators may be other known types of indicators such as electronic sensors and displays. The input piston  58  includes a linkage  78  adapted to be acted on by an external force, such as a manual force exerted by a person operating the measuring device  10 . The output piston  62  includes an output linkage  80  adapted to act on the shoulder  44  of the contact lever  40 . 
         [0018]    The measuring device  10  may include common devices such as thermometer, moisture sensor, barometer and light sensor adapted to provide information relative to surface and atmospheric conditions. Examples of such devices may be found in an electronic home weather station. 
       INDUSTRIAL APPLICABILITY 
       [0019]    In operation the measuring device  10  of the present invention is placed against the surface  12  with the bottom surface  36  of the collar  30  adjacent the surface  12 . In this position, the housing  14  is substantially perpendicular to the surface  12 . A manual force is applied to the housing  14  to cause the contact levers  40  to engage the surface  12 . The preload spring  38  thereby is compressed causing contact levers  40  to engage the surface  12  with a predetermined and repeatable force. The actuator  52  is then actuated causing the contact surface  42  of the contact lever  40  to move along the surface  12 . The force required to move the contact surface  42  is thereby displayed on the indicator  76 . By providing multiple readings at predetermined intervals, and at various locations on the surface  12  the team may monitor changes in the tractive condition of the surface  12 . 
         [0020]    In operation, the present invention provides an indication of the surface  12 . Of utmost importance is the ability of the measuring device  10  to provide a consistent and repeatable indication at the specific time that the measurement is taken. By using the measuring device repeatedly over the course of a day, it is possible to monitor changes in the condition of the surface  12  and advise a driver of those changes. 
         [0021]    It will be apparent to those skilled in the art that various modifications and variations can be made to the disclosed measuring device. Other embodiments will be apparent to those skilled in the art from consideration of the specification and practice of the disclosed measuring device. It is intended that the specification and examples be considered as exemplary only, with a true scope being indicated by the following claims and their equivalent.