A bridge paving device includes one or more reference receivers to locate the bridge paving device in three-dimensional space. A computer apparatus receives the location of the bridge paving device and associates the location with a bridge paving design profile. The computer apparatus independently actuates a system of hydraulic actuators of the bridge paving device to level and orient the bridge paving device regardless of the travel surface the linear movement elements are running on. Additional hydraulic actuators may adjust the shape of the bridge paving device over time as the bridge paving device travels a linear distance of the bridge to be paved. The shape adjustment alters a crown or inversion applied to the bridge such that run-off characteristics are more variable and controllable along the entire span of the bridge.

PRIORITY 
     The present application claims the benefit under 35 U.S.C. §119(e) of U.S. Provisional Application Ser. No. 62/011,687, filed Jun. 13, 2014, which is incorporated herein by reference. 
    
    
     FIELD OF THE INVENTION 
     The present invention is directed generally toward paving machines, and more particularly toward paving machines having cylinder finishers. 
     BACKGROUND OF THE INVENTION 
     Bridge paving is one of the most technical and labor intensive paving applications. Typically, once the structure of a bridge is in place, guide elements are placed along the periphery of the area to be paved. The guide elements define a reference, and possibly a useable surface, for the linear movement elements of a paving machine. 
     Because the guide elements define a reference from which all paving operations will be measured, the guide elements must be positioned very precisely. Often, paving crews spend weeks or months surveying and confirming the location of each guide element to ensure that the resulting reference conforms to a design profile for the bridge. 
     Once all guide elements are in position, the paving machine is sent through a test run to ensure the paving machine can traverse the guide elements. Then an actual paving operation is performed. 
     The entire process can take several months, but the actual paving operation can be performed in a single day. Consequently, it would be advantageous if an apparatus existed that is suitable for allowing a bridge paving machine to pave a bridge more efficiently and with less preparation than the prior art. 
     SUMMARY OF THE INVENTION 
     Accordingly, the present invention is directed to a novel method and apparatus for allowing a bridge paving machine to pave a bridge more efficiently and with less preparation than the prior art. 
     In one embodiment, a bridge paving device includes one or more reference prisms to locate the bridge paving device in three-dimensional space. A computer apparatus receives the location of the bridge paving device and associates the location with a bridge paving design profile. The computer apparatus independently actuates a system of hydraulic actuators corresponding to the linear movement elements of the bridge paving device to level and orient the bridge paving device regardless of the travel surface the linear movement elements are running on. Furthermore, one or more powered transition adjusters may adjust the frame shape of the bridge paving device over time as the bridge paving device travels a linear distance of the bridge to be paved. The varying frame shape may alter the crown applied to the bridge such that run-off characteristics are more variable and controllable along the entire span of the bridge. 
     In another embodiment, the bridge paving device includes one or more satellite receivers for receiving a positioning signal to locate the bridge paving device in three dimensional space. 
     It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention claimed. The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate an embodiment of the invention and together with the general description, serve to explain the principles. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The numerous advantages of the present invention may be better understood by those skilled in the art by reference to the accompanying figures in which: 
         FIG. 1  shows a block diagram of a computer apparatus according to one embodiment of the present invention; 
         FIG. 2  shows a perspective environmental view of a bridge paving device according to one embodiment of the present invention; 
         FIG. 3  shows a front environmental view of a bridge paving device according to an embodiment of the present invention; 
         FIG. 4  shows a front environmental view of a bridge paving device according to another embodiment of the present invention; 
         FIG. 5  shows another environmental view of a bridge paving device according to the present invention; and 
         FIG. 6  shows a flowchart of a method for controlling a bridge paving device according to one embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Reference will now be made in detail to the subject matter disclosed, which is illustrated in the accompanying drawings. The scope of the invention is limited only by the claims; numerous alternatives, modifications and equivalents are encompassed. For the purpose of clarity, technical material that is known in the technical fields related to the embodiments has not been described in detail to avoid unnecessarily obscuring the description. 
     Referring to  FIG. 1 , a block diagram of a computer apparatus according to one embodiment of the present invention is shown. In at least one embodiment, a bridge paving device includes a processor  100 , memory  102  connected to the processor  100  for storing computer executable program code and a data storage element  104  configured to store a bridge paving profile. 
     The processor  100  may also be connected to an antenna  106 . The antenna  106  may be configured to receive location data from a surveying instrument such as a Total Station. Alternatively, or in addition, the antenna  106  may receive a satellite based location signal such as a GPS signal for determining the location of the Bridge paving device. Furthermore, a second antenna  106  may also be connected to the processor  100 ; the second antenna  106  may receive a second satellite based location signal such that the known difference in location between the first antenna  106  and the second antenna  106  may be used to determine an orientation of the bridge paving device. Alternatively, or in addition, the processor  100  may receive orientation information through the antenna  106  from a separate surveying instrument. 
     The processor  100  may correlate the location and orientation information to the bridge paving profile. The processor  100  thereby knows the location and orientation of the bridge paving device as it pertains to a desired location and orientation defined in the bridge paving profile. The processor  100  may actuate one or more hydraulic actuators  108 ,  110 ,  112 ,  114 , for example through a hydraulic control system, to adjust the position and orientation of the bridge paving device to conform to parameters defined by the bridge paving profile. 
     The processor  100  may receive updated location and orientation information through the antenna  106 , and periodically correlate the updated location and orientation information to the bridge paving profile. The processor  100  continuously adjusts the hydraulic actuators  108 ,  110 ,  112 ,  114  to maintain the bridge paving device within the defined parameters as the bridge paving device moves linearly along the surface being paved. 
     Furthermore, the processor  100  may be connected to one or more powered transition adjusters  116  connected to portions of the bridge paving device. In at least one embodiment, the powered transition adjusters  116  are configured to adjust the shape of the main support structure of the bridge paving device to create or adjust a crown or inversion in the paved surface. Alternatively, the height of a bridge paving carriage may vary along both the width of the paved surface and the length of the bridge span as defined by the bridge paving profile according to desired run-off parameters. 
     Referring to  FIG. 2 , a perspective environmental view of a bridge paving device according to one embodiment of the present invention is shown. In at least one embodiment, a bridge paving device  200  includes a power and control unit  204  configured to power and control hydraulic actuators  208 ,  210 ,  212 ,  214  associate with the linear movement elements that move the bridge paving device linearly along a bridge structure to be paved. Linear movement elements may include tracks, wheels, bogies or any other suitable device for producing linear movement in the bridge paving device. The power and control unit  204  also controls the motion of a paving carriage  202  which may comprise a cylinder finisher and in at least one embodiment, one or more powered transition adjusters  216  configured to adjust the shape of the main support structure. Different shapes of the main support structure may alter the shape of a crown or inversion in the paved surface. Furthermore, different shapes of the main support structure coupled with adjustments to the paving carriage  202  may allow the power and control unit  204  to apply continuous, variable slopes to the paved surface. 
     The power and control unit  204  may also include an antenna configured to receive location data from a surveying instrument such as a Total Station  220 . Alternatively, or in addition, the power and control unit  204  may receive a satellite  218  based location signal such as a GPS signal for determining the location of the Bridge paving device  200 . The bridge paving device  200  may be equipped with reference features such as surveying prisms, or GPS receivers or both, sufficient to locate and orient the bridge paving device  200  with reference to a bridge paving profile. 
     The power and control unit  204  may actuate one or more hydraulic actuators  208 ,  210 ,  212 ,  214  associated with the linear movement elements that drive the bridge paving device  200  to adjust the position and orientation of the bridge paving device  200  to conform to parameters defined by the bridge paving profile. 
     The power and control unit  204  may receive updated location and orientation information and periodically correlate the updated location and orientation information to the bridge paving profile. The power and control unit  204  continuously adjusts the hydraulic actuators  208 ,  210 ,  212 ,  214  to maintain the bridge paving device  200  within the defined parameters as the bridge paving device  200  moves linearly along the surface being paved. 
     In at least one embodiment, a bridge paving device  200  may be configured to distribute the load of the bridge paving device  200  on the bridge structure by directing the linear movement elements on one side of the bridge paving device  200  to maintain a relative position further along the bridge with reference to the linear movement elements on the other side. The bridge paving device  200  is thereby skewed in the direction of linear travel. Where a bridge paving profile includes complex crown or inversion features, such complexity is significantly increased where the bridge paving device  200  is skewed. Such complexity may require the power and control unit  204  to maintain intricate control and interrelation of the paving carriage  202  movement and powered transition adjuster  216 . 
     Referring to  FIG. 3 , a front environmental view of a bridge paving device according to the present invention is shown. In at least one embodiment, a bridge paving device  300  includes a power and control unit  304  configured to power and control hydraulic actuators  308 ,  312 , associate with the linear movement elements that move the bridge paving device linearly along a bridge structure to be paved, the motion of a paving carriage  302  and in at least one embodiment, one or more powered transition adjusters  316  configured to apply a crown  318  to a surface being paved. 
     The power and control unit  304  may include an antenna configured to receive location data from a surveying instrument or a satellite based location signal for determining the location of the bridge paving device  300  with reference to a bridge paving profile. The bridge paving profile may include a crown  318  or inversion that may vary along the length of the bridge span. 
     The powered transition adjusters  316  may alter the shape in the main support structure of the bridge paving device  300  to create or adjust a crown  318  or inversion in the paved surface. Alternatively, a paving carriage  302  may be raised and lowered according to the bridge paving profile. The height of the bridge paving carriage  302 , including a cylinder finisher, may vary along both the width of the paved surface and the length of the bridge span as defined by the bridge paving profile according to desired run-off parameters. 
     Referring to  FIG. 4 , a front environmental view of a bridge paving device according to another embodiment of the present invention is shown. In at least one embodiment, a bridge paving device  400  includes a power and control unit  404  configured to power and control hydraulic actuators  408 ,  410 ,  412 ,  414  associate with the linear movement elements that move the bridge paving device linearly along a bridge structure to be paved. The power and control unit  404  also controls the motion of a paving carriage  402  which may comprise a cylinder finisher and in at least one embodiment, one or more powered transition adjusters  416 ,  420  configured to change the shape of the main support structure of the bridge paving device  400 . Different shapes of the main support structure may alter the shape of a crown or inversion in the paved surface. Also, where a first powered transition adjuster  416  is configured to alter the shape of a first portion of the main support structure and a second powered transition adjuster  420  is configured to alter the shape of a second position of the main support structure, the power and control element  404  may induce a disparity of shapes in the main support structure to produce a desired frame shape and thereby a desired paved surface slope. Furthermore, different shapes of the main support structure coupled with adjustments to the paving carriage  402  may allow the power and control unit  404  to apply continuous, variable slopes to the paved surface. 
     While  FIG. 4  shows a bridge paving device  400  with two powered transition adjusters  416 ,  420 , more than two powered transition adjusters  416 ,  420  are contemplated. More than two powered transition adjusters  416 ,  420  may be useful for producing a paved surface having a complex design profile. Complex design profiles may include multiple crowns or inversions to achieve desired drainage characteristics, banked portions, or any other features that require shape alterations to the main support structure that are unachievable with two powered transition adjusters  416 ,  420 . 
     Referring to  FIG. 5 , another environmental view of a bridge paving device according to the present invention is shown. In at least one embodiment, a bridge paving device  500  includes a power and control unit  504  configured to power and control hydraulic actuators  508 ,  512  associate with the linear movement elements that move the bridge paving device linearly along a bridge structure to be paved  518 , the motion of a paving carriage  502  including a cylinder finisher and in at least one embodiment, one or more powered transition adjusters  516  configured to adjust the shape of the main support structure according to a desired paving profile to apply a crown or inversion to the surface being paved  518 . 
     The power and control unit  504  may also include an antenna configured to receive location data from a surveying instrument such as a Total Station  520 . Alternatively, or in addition, the power and control unit  504  may receive a satellite based location signal such as a GPS signal for determining the location of the Bridge paving device  500 . The bridge paving device  500  may be equipped with reference features such as surveying prisms, or GPS receivers or both, sufficient to locate and orient the bridge paving device  500  with reference to a bridge paving profile. 
     The linear movement elements that move the bridge paving device  500  linearly along the bridge structure to be paved  518  may run on guide elements  522  positioned according to the paving profile during construction of the bridge structure to be paved. In at least one embodiment, the tolerances for the location of the guide elements  522  are significantly less rigid as compared to the prior art. 
     Referring to  FIG. 6 , a flowchart of a method for controlling a bridge paving device according to one embodiment of the present invention is shown. In at least one embodiment, a bridge paving device receives  600  a bridge design profile that defines the necessary location of the bridge paving device, and in at least one embodiment, a variable crown or inversion to be applied to the paved surface. The bridge paving device also receives  602  location data corresponding to the position of the bridge paving device and orientation data  604  corresponding to the orientation of the bridge paving device. 
     The bridge paving device correlates  606  the location and orientation data to the bridge design profile and adjusts  608  one or more hydraulic actuators to bring the location and orientation of the bridge paving device in line with the parameters of the bridge design profile. During paving, the bridge paving device continuously monitors  610  the location and orientation of the bridge paving device, either through continuously receiving updated data or adjusting the known location and orientation based on operations executed by the bridge paving device or both. Based on the updated location and orientation data, and the parameters of the bridge design profile, the bridge paving device may periodically adjust  612  one or more hydraulic actuators or one or more powered transition adjusters or both simultaneously. 
     A person skilled in the art may appreciate that while the exemplary embodiments disclosed herein describe hydraulic actuators, additional embodiments are envisioned. For example, linear mechanical actuators, screw jacks or other substantially equivalent mechanisms are contemplated. 
     It is believed that the present invention and many of its attendant advantages will be understood by the foregoing description of embodiments of the present invention, and it will be apparent that various changes may be made in the form, construction, and arrangement of the components thereof without departing from the scope and spirit of the invention or without sacrificing all of its material advantages. The form herein before described being merely an explanatory embodiment thereof, it is the intention of the following claims to encompass and include such changes.