Title of Invention: RAILCAR TRUCK ROLLER BEARING ADAPTER PAD SYSTEMS Abstract: A railcar truck and adapter pad system for placement between a roller bearing and side frame pedestal roof of a three-piece railcar truck. Many different features of the pad and/or the adapter-pad interface are configured to improve stiffness characteristics to satisfy both curving and high speed performance of the railcar truck. Detailed Description: CROSS-REFERENCE TO RELATED APPLICATIONS This patent application claims the benefit of U.S. Provisional Patent Application No. 61/921,961, filed Dec. 30, 2013, entitled Railcar Truck Roller Bearing Adapter-Pad Systems, and U.S. Provisional Patent Application No. 62/065,438, filed Oct. 17, 2014, entitled Railcar Truck Roller Bearing Adapter-Pad Systems which are incorporated by reference. TECHNICAL FIELD The present disclosure relates to railcar trucks, and more particularly to roller bearing adapter and adapter-pad systems that can improve stiffness, damping, and displacement characteristics to satisfy both curving and high speed performance of a three-piece railcar truck. BACKGROUND The conventional railway freight car truck in use in North America for many decades has been the three-piece truck, comprising a pair of parallel side frames connected by a transversely mounted bolster. The bolster is supported on the side frames by spring groups consisting of a number of individual coil springs. The wheelsets of the truck are received in bearing adapters placed in leading and trailing pedestal jaws in the side frames, so that axles of the wheelsets are parallel in a transverse or lateral position relative to the two rails. The railway car is mounted on the center plate of the bolster, which allows the truck to rotate with respect to the car. The spring groups and side frame to bolster clearance stops permit the side frames to move somewhat with respect to the bolster, about the longitudinal, vertical and transverse or lateral axes. It has long been desired to improve the performance of the three-piece truck. Resistance to lateral and longitudinal loads and truck performance can be characterized in terms of one or more of the following well-known phenomena. “Parallelogramming” occurs when one side frame moves forward longitudinally with respect to the other, such that the leading and trailing wheel sets remain parallel to each other but they are not perpendicular to the rails, as may happen when a railway car truck encounters a curve. This action of parallelogramming side frames is also referred to as truck warp. “Hunting” describes an oscillating sinusoidal longitudinal and lateral movement of the wheelsets that causes the railcar body to move side-to-side. This sinusoidal movement is the harmonic oscillation caused by the tapered profile of the wheelset. While the tapered profile promotes natural oscillation of the wheelset, it is also the primary feature that allows the wheelsets to develop a rolling radius difference and negotiate curves. Hunting may be dangerous when the oscillations attain a resonant frequency. Hunting is more likely to occur when there is a lack of proper alignment in the truck as manufactured, or developed over time through various operating conditions such as wear of the truck components. Hunting is also more likely to occur when the railcar is operated at higher speeds. The speed at which hunting is observed to occur is referred to as the “hunting threshold.” Several approaches have been tried to improve the stability of the standard three-piece truck to prevent parallelogramming and hunting, while at the same time ensuring that the truck is able to develop the appropriate geometry to accommodate the different distances traveled by the wheels on the inside and outside of a turn, respectively. Additional improvement is desired, both to meet truck hunting requirements as well as to simultaneously improve stiffness, damping, and displacement characteristics that yield good high speed and curving performance. BRIEF SUMMARY OF THE INVENTION This Summary provides an introduction to some general concepts relating to this invention in a simplified form that are further described below in the Detailed Description. Aspects of the disclosure herein also relate to adapter pads and adapter pad system. In one example, the disclosure provides roller bearing adapter pad system configured for use with a three-piece truck having AAR standard geometry including a roller bearing adapter configured to engage a roller bearing, the roller bearing adapter having a crowned top surface, and a bottom surface configured to engage a roller bearing. The adapter pad system can also include an adapter pad engaged with the roller bearing adapter and configured to engage a side frame pedestal roof, the adapter pad including a continuous top plate having a central portion and first and second lateral edges; a continuous bottom plate having a central portion and first and second upturned regions projecting upwardly from opposite edges of the central portion; and an elastomeric member disposed between the first lateral edge of the top plate and the first upturned region of the bottom plate, between the central sections of the top and bottom plates, and between the second lateral edge of the top plate and the second upturned region of the bottom plate; wherein a top surface of the top plate is raised above a top surface of the bottom plate. In another example, the disclosure provides a roller bearing adapter pad system configured for use with a three-piece truck having AAR standard geometry including a roller bearing adapter configured to engage a roller bearing, the roller bearing adapter having a top surface, and a bottom surface configured to engage a roller bearing. The adapter pad system can also include an adapter pad engaged with the roller bearing adapter and configured to engage a side frame pedestal roof, the adapter pad including a continuous top plate an elastomeric member disposed between the top plate and the top surface of the roller bearing adapter; wherein the elastomeric member is bonded to the top plate and the top surface of the roller bearing adapter, and wherein the combined adapter, top plate, and elastomeric member provide a longitudinal stiffness of at least 45,000 pounds per inch through a longitudinal displacement of the top plate relative to the adapter of up to 0.139 inches from a central position, a lateral stiffness of at least 45,000 pounds per inch through a lateral displacement of the top plate relative to the adapter of up to 0.234 inches from the central position, and a rotational stiffness of at least 250,000 pound*inches per radian of rotation through a rotational displacement of the top plate relative to the adapter of up to 41 milliradians from the central position when a vertical load of 35,000 pounds is applied to the central portions of the adapter pad. In another example, the disclosure provides a roller bearing adapter pad system configured for use with a three-piece truck having AAR standard including a roller bearing adapter configured to engage a roller bearing, the roller bearing adapter having a top surface, and a bottom surface configured to engage a roller bearing. The adapter pad system can also include an adapter pad engaged with the roller bearing adapter and configured to engage a side frame pedestal roof, the adapter pad including an elastomeric member with a top surface configured to engage a side frame pedestal roof, and a bottom surface engaged with the top surface of the roller bearing adapter, wherein the elastomeric member is bonded to the top surface of the roller bearing adapter, and wherein the combined adapter and elastomeric members provide a longitudinal stiffness of at least 45,000 pounds per inch through a longitudinal displacement of the side frame relative to the adapter of up to 0.139 inches from a central position, a lateral stiffness of at least 45,000 pounds per inch through a lateral displacement of the side frame relative to the adapter of up to 0.234 inches from the central position, and a rotational stiffness of at least 250,000 pound*inches per radian of rotation through a rotational displacement of the side frame relative to the adapter of up to 41 milliradians from the central position when a vertical load of 35,000 pounds is applied to the central portions of the adapter pad. In another example, the disclosure provides a roller bearing adapter pad system configured for use with a three-piece truck having AAR standard geometry including a roller bearing adapter configured to engage a roller bearing, the roller bearing adapter having a crowned top surface; a bottom surface configured to engage a roller bearing; and first and second vertical shoulders projecting upwardly from opposite lateral edges of the top surface. The adapter pad system can include an adapter pad engaged with the roller bearing adapter and configured to engage a side frame pedestal roof, the adapter pad including a continuous plate disposed between the side frame pedestal roof and roller bearing adapter top surface; a plurality of elastomeric members disposed between the side frame pedestal roof and roller bearing adapter top surface, wherein the plurality of elastomeric members are bonded to the continuous plate and positioned to shear under displacement of the side frame relative to the adapter, and wherein the adapter pad provides a longitudinal stiffness of at least 45,000 pounds per inch through a longitudinal displacement of the side frame relative to the adapter of up to 0.139 inches from a central position, a lateral stiffness of at least 45,000 pounds per inch through a lateral displacement of the side frame relative to the adapter of up to 0.234 inches from the central position, and a rotational stiffness of at least 250,000 pound*inches per radian of rotation through a rotational displacement of the side frame relative to the adapter of up to 41 milliradians from the central position when a vertical load of 35,000 pounds is applied to the central portions of the adapter pad. In another example, the disclosure provides, a roller bearing adapter pad system configured for use with a three-piece truck having AAR standard geometry including a roller bearing adapter configured to engage a roller bearing, the roller bearing adapter having a crowned top surface, and a bottom surface configured to engage a roller bearing. The adapter pad system can also include an adapter pad engaged with the roller bearing adapter and configured to engage a side frame pedestal roof; a damper engaged with the roller bearing adapter at a first end and engaged with a side frame; wherein the damper is configured to dampen forces of a wheelset in the longitudinal direction. In another example, the disclosure provides a roller bearing adapter pad system configured for use with a three-piece truck having AAR standard geometry including a roller bearing adapter configured to engage a roller bearing, the roller bearing adapter having a crowned top surface; a bottom surface configured to engage a roller bearing; and first and second vertical shoulders that project upwardly from opposite lateral edges of the top surface. The adapter pad system can also include an adapter pad engaged with the roller bearing adapter and configured to engage a side frame pedestal roof, the adapter pad including a continuous top plate having a central portion, and first and second upturned regions projecting upwardly from opposite edges of the central portion; a continuous bottom plate having a central portion, and first and second upturned regions projecting upwardly from opposite edges of the central portion; a first outer elastomeric member disposed between the first upward projecting portions of the top and bottom plates; and wherein the thickness of the adapter is no greater than 0.4 inches as measured at the longitudinal centerline from bottom surface to the crowned top surface of the roller bearing adapter. In another example the disclosure provides a roller bearing adapter pad system configured for use with a three-piece truck having AAR standard geometry including a roller bearing adapter configured to engage a roller bearing, the roller bearing adapter having crowned top surface, and a bottom surface configured to engage a roller bearing. The roller bearing adapter pad system can also include an adapter pad engaged with the roller bearing adapter and configured to engage a side frame pedestal roof including a continuous top plate having a central portion and first and second lateral edges; a continuous bottom plate having a central portion and first and second upturned regions projecting upwardly from opposite edges of the central portion; and an elastomeric member disposed between the first lateral edge of the top plate and the first upturned region of the bottom plate, between the central sections of the top and bottom plates, and between the second lateral edge of the top plate and the second upturned region of the bottom plate; wherein a top surface of the top plate is raised above a top surface of the bottom plate; and wherein the elastomeric member includes at least one substantially vertical section and at least one shim within the at least one substantially vertical section. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1A is a perspective view of a standard 3-piece truck. FIG. 1B is an exploded view of a standard 3-piece truck. FIG. 2 is a perspective view of a roller bearing adapter and adapter pad according to aspects of the disclosure. FIG. 3 is a cross-sectional view of roller bearing adapter, adapter pad, and a side frame according to aspects of the disclosure. FIG. 3A is a detail view of a portion of FIG. 3. FIG. 3B is a detail view of a portion of FIG. 3. FIG. 4 is a perspective view of a roller bearing adapter according to aspects of the disclosure. FIGS. 5A-5D are perspective views of roller bearing adapters according to aspects of the disclosure. FIG. 6 is a cross-sectional view of the roller bearing adapter of FIG. 4 taken along a centerline. FIG. 7 is a top view of the roller bearing adapter of FIG. 4. FIG. 8 is a side view of the roller bearing adapter of FIG. 4. FIG. 9 is a front view of the roller bearing adapter of FIG. 4. FIG. 10 is a cross-sectional view taken along line A-A of FIG. 8. FIG. 11 is a top view of an adapter pad according to aspects of the disclosure. FIG. 11A is a cross-sectional view taken along line A-A of FIG. 11. FIG. 11B is a cross-sectional view taken along line B-B of FIG. 11. FIG. 11C is a detail view of detail G of FIG. 11. FIG. 12 is a side view of a bottom plate of an adapter pad according to aspects of the disclosure. FIG. 13A is a top view of an adapter pad according to aspects of the disclosure. FIG. 13B is a cross-sectional view taken along the longitudinal line of FIG. 13A. FIG. 13C is a section view along the longitudinal center centerline of an adapter pad and a portion of a roller bearing adapter according to aspects of the disclosure. FIG. 13D is a perspective view of an adapter pad according to aspects of the disclosure with all elastomeric material removed including a ground strap. FIG. 13E is a perspective view of an adapter pad according to aspects of the disclosure including a ground strap. FIG. 14 is an exemplary graph depicting adapter pad lateral force vs. displacement according to aspects of the disclosure. FIG. 15 is an exemplary graph depicting temperature vs. time during loading of an adapter pad according to aspects of the disclosure. FIG. 16A is a top view of an adapter pad without the top plate according to aspects of the disclosure. FIG. 16B is cross-sectional view of adapter pad according to aspects of the disclosure. FIG. 17A is a top view of an adapter pad according to aspects of the disclosure. FIG. 17B is a top view of the adapter pad of FIG. 17A depicting longitudinal displacement. FIG. 17C is a top view of the adapter pad of FIG. 17A depicting lateral displacement. FIG. 17D is a top view of the adapter pad of FIG. 17A depicting rotational displacement. FIG. 18 is a depiction of a method of manufacturing an adapter pad according to aspects of the disclosure. FIG. 19 is a perspective view of an elastomeric member of an adapter pad according to aspects of the disclosure. FIG. 20A-C are vertical sectional views of a portion of an adapter pad according to aspects of the disclosure showing various geometries for the plurality of gaps, with the adapter pad in an unloaded configuration. FIG. 21A-C are each views of the respective FIGS. 20a-20c schematically showing the geometry of the gaps altered when load is applied to the adapter pad. FIG. 22 is a sectional view of a portion of an adapter pad according to aspects of the disclosure, showing a representative alignment of the plurality of gaps within the elastomeric portion. FIG. 23 is a sectional view of a portion of the adapter pad according to aspects of the disclosure showing a plurality of gaps extending only a partial thickness of the elastomeric layer. FIG. 24 is a depiction of a method of manufacturing an adapter pad according to aspects of the disclosure. FIG. 25 is a depiction of a method of manufacturing an adapter pad according to aspects of the disclosure. FIGS. 25A-25I are perspective views of adapter pads according to aspects of the disclosure. FIG. 26 is a depiction of a method of manufacturing an adapter pad according to aspects of the disclosure. FIG. 27 is an exemplary graph depicting testing of an adapter pad according to aspects of the disclosure. FIG. 28A is a perspective view of an adapter pad according to aspects of the disclosure. FIG. 28B is a perspective view of an adapter pad according to aspects of the disclosure. FIG. 28C is a perspective view of an adapter pad according to aspects of the disclosure. FIG. 29A is a perspective view of a roller bearing adapter and adapter pad according to aspects of the disclosure. FIG. 29B is a front view of the adapter pad of FIG. 29A. FIG. 29C is a perspective view of a roller bearing adapter and adapter pad according to aspects of the disclosure. FIG. 30 is a perspective view of an adapter pad according to aspects of the disclosure. FIG. 31 is a perspective view of a roller bearing adapter and adapter pad according to aspects of the disclosure. FIG. 32A is a perspective view of a roller bearing adapter and adapter pad according to aspects of the disclosure. FIG. 32B is a cross-sectional perspective view of the roller bearing adapter and adapter pad of FIG. 32A. FIG. 33A is a perspective view of a side frame, roller bearing adapter and adapter pad according to aspects of the disclosure. FIG. 33B is a perspective view of the roller bearing adapter and adapter pad of FIG. 33A. FIG. 33C is a cross-sectional perspective view the roller bearing adapter and adapter pad of FIGS. 33A and 33B. FIG. 34A is a perspective view of a side frame, roller bearing adapter and adapter pad according to aspects of the disclosure. FIG. 34B is a perspective view of the roller bearing adapter and adapter pad of FIG. 34A. FIG. 34C is a top cross-sectional view of the side frame, roller bearing adapter and adapter pad of FIG. 34A. FIG. 35 is a perspective view of a roller bearing adapter and adapter pad according to aspects of the disclosure. FIG. 36A is a front view of a roller bearing adapter and adapter pad according to aspects of the disclosure. FIG. 36B is a perspective view of the roller bearing adapter and adapter pad of FIG. 36A. FIG. 36C is a top view of the roller bearing adapter and adapter pad of FIG. 36A. FIG. 37A is a top view of a roller bearing adapter and adapter pad according to aspects of the disclosure. FIG. 37B is a perspective view of the roller bearing adapter and adapter pad of FIG. 37A. FIG. 38A is a front cross-sectional view of a roller bearing adapter and adapter pad according to aspects of the disclosure. FIG. 38B is a perspective view of the roller bearing adapter and adapter pad of FIG. 38A. FIG. 39 is a front view of a roller bearing adapter and adapter pad according to aspects of the disclosure. FIG. 40 is a perspective view of the roller bearing adapter and adapter pad of FIG. 39. FIG. 41 is a front view of a roller bearing adapter and adapter pad according to aspects of the disclosure. FIG. 42 is a perspective view of the roller bearing adapter and adapter pad of FIG. 41. FIG. 43 is a perspective view of a side frame, roller bearing adapter and adapter pad according to aspects of the disclosure including a damper. FIG. 44 is a side view of the side frame, roller bearing adapter and adapter pad including a damper of FIG. 43. FIG. 45A is a partially exploded perspective view of a roller bearing adapter and adapter pad according to aspects of the disclosure. FIG. 45B is a perspective view of a side frame and the roller bearing adapter and adapter pad of FIG. 45A. FIG. 46 is a perspective view of a roller bearing adapter and adapter pad according to aspects of the disclosure. FIG. 47A is a bottom perspective view of an adapter pad according to aspects of the disclosure. FIG. 47B is a perspective view of the adapter pad of FIG. 47A. FIG. 47C is a perspective view of the adapter pad of FIG. 47A including a roller bearing adapter according to aspects of the disclosure. DETAILED DESCRIPTION In the following description of various example structures according to the invention, reference is made to the accompanying drawings, which form a part hereof, and in which are shown by way of illustration various example devices, systems, and environments in which aspects of the invention may be practiced. It is to be understood that other specific arrangements of parts, example devices, systems, and environments may be utilized and structural and functional modifications may be made without departing from the scope of the present invention. Also, while the terms “top,” “bottom,” “front,” “back,” “side,” “rear,” and the like may be used in this specification to describe various example features and elements of the invention, these terms are used herein as a matter of convenience, e.g., based on the example orientations shown in the figures or the orientation during typical use. Additionally, the term “plurality,” as used herein, indicates any number greater than one, either disjunctively or conjunctively, as necessary, up to an infinite number. Nothing in this specification should be construed as requiring a specific three dimensional orientation of structures in order to fall within the scope of this invention. Also, the reader is advised that the attached drawings are not necessarily drawn to scale. In general, aspects of this invention relate to a railcar truck, and railcar truck roller bearing adapters and adapter pads. According to various aspects and embodiments, the railcar truck and the railcar truck roller bearing adapters and adapter pads may be formed of one or more of a variety of materials, such as metals (including metal alloys), polymers, and composites, and may be formed in one of a variety of configurations, without departing from the scope of the invention. It is understood that the railcar truck roller bearing adapters and adapter pads may contain components made of several different materials. Additionally, the components may be formed by various forming methods. For example, metal components, may be formed by forging, molding, casting, stamping, machining, and/or other known techniques. Additionally, polymer components, such as elastomers, can be manufactured by polymer processing techniques, such as various molding and casting techniques and/or other known techniques. The various figures in this application illustrate examples of railcar trucks, railcar truck roller bearing adapters, and adapter pads according to this invention. When the same reference number appears in more than one drawing, that reference number is used consistently in this specification and the drawings refer to the same or similar parts throughout. As shown in FIGS. 1A and 1B, a typical railroad freight car truck includes an assembly made up of two wheel sets 1 each including two wheels 2, two side frames 4, one bolster 6, two spring groups 8, a friction damping system, and four adapters 10. FIGS. 1A and 1B depict an example truck assembly. The side frames 4 are arranged longitudinally, e.g., in the direction of the rails upon which the truck sits. The bolster 6 is aligned transversely or laterally with respect to the side frames 4 and extends through the middle of each side frame 4. The bolster bowl 12 is the round section of the bolster 6 that includes a rim that protrudes upward. The body centerplate of the car body rests in the bolster bowl 12 and acts as a rotation point for the truck and car body. It is at this interface that the majority of the vertical load of the freight car is reacted. Usually, the bolster bowl 12 is equipped with wear plates or a wear liner so that the bolster casting 6 is prevented from wear during the service life of the freight car. Also on the top surface of the bolster 6 and located 25 inches off the centerline are the side bearings 14, which can help stabilize the car body and can provide some prevention of truck hunting if they are of the constant contact type. The side bearings 14 shown in FIG. 1B are not of the constant contact type but rather consist of rollers and a cage. The bolster 6 rests on top of spring groups 8 that are supported underneath by the spring seat of the side frames. Additional springs, often called snubber or side springs 17, can also be part of the spring group and rest on the spring seat extending upward to the bottom of friction wedges 16 that can be part of the friction damping system. The friction wedges 16 can be located in pockets at the end of and to each side of the bolster 6. The friction wedge pockets of the bolster can be angled, typically at an angle of about 60° from horizontal matching the angle surface of the friction wedges. The opposite face of a friction wedge 16 is typically vertical and contacts what is called the column face of the side frame. The spring force of the snubber springs 17 pushes the friction wedge 16 against the angled surface of the bolster friction wedge pocket which creates a reaction force against the vertical column face of the side frame. As the bolster 6 moves up and down under the load from the freight car resting on the truck, the sliding of the friction wedge 16 against the column face can create column friction damping. This damping can provide for a dissipation of energy that prevents the freight car from developing undesired vibrations/oscillations when moving in railroad service. It is also these forces acting between the bolster 6 and side frame 4 through the friction wedges 16 that seeks to prevent the truck from taking on a parallelogram geometry when under operation. Hard stops, such as the gibs and rotation stops, help prevent trucks from taking on an extreme parallel shape. This resistance to parallelogramming is often called warp stiffness. As shown in FIGS. 1A and 1B, the wheel sets 1 of the truck assembly consist of two wheels 2, an axle 3, and two roller bearings 5. The wheels are press fit onto the raised wheel seats of the axle. The journal of the axles extend outboard of the wheels and provide the mounting surface for the roller bearings 5. The roller bearings 5 are press fit onto the axle journals. The interface between the roller bearings 5 and the side frames 4 can consist of a bearing adapter 7. Typically railroad freight car trucks have been equipped with metal adapters that are precisely machined to fit on the roller bearings rather tightly while providing a looser fit to the steel side frame pedestals which envelope the interface between the roller bearings and the side frames. This interface provides a small movement between the wheel sets and the side frames which is controlled by the vertical load that exists from the freight car and the frictional forces that exist between the sliding metallic surface on top of the adapter, referred to as the adapter crown, and the bottom of the steel pedestal roof which is usually equipped with a steel wear plate. Because the vertical load varies with the lading weight contained in the freight car and with the rocking motion of the freight car on the truck, the frictional forces at the metal adapter crown and steel pedestal roof wear plate can vary considerably and are not controlled in the typical truck. This metal to metal connection requires large wheelset forces to force sliding at the interfacing surface due to the stick-slip nature of metal sliding connections. More recent truck designs, such as those trucks qualified under the American Association of Railroads (“AAR”) M-976 specification, now include an adapter pad at the interface between the steel adapter and the pedestal roof. Some adapter pad systems have been successful in lowering wheelset forces during railcar curving by allowing low stiffness compliance between the side frame and axle. This added compliance created by the adapter pad also reduces the force it takes to pull or push a railcar through a curve as required in the M-976 specification, which is incorporated herein by reference. Adversely, these designs have lowered the speed at which the car resonates during tangential track travel, otherwise described as lowering the hunting speeds of the cars. Lowering the hunting speed is a disadvantage because it limits the operating speeds of the trains and increases the risk of derailing cars or damaging track. Other designs utilize premium side frame squaring devices such as transoms, frame bracing, steering arms, spring planks, yaw dampers, cross bracing, or additional friction wedges to improve the hunting performance. These systems, generally referred to as premium truck technology, typically increase the wheelset forces and therefore the pulling resistance during curving. In addition to increasing curve resistance, these designs have traditionally increased truck maintenance costs due to the added wear components and system complexity. Adapter pad system embodiments described herein can meet the curving performance criteria set forth in M-976, without decreasing the critical hunting threshold. The adapter pad systems described herein also do not require any additional side frame squaring devices, such as transoms, frame bracing, steering arms, spring planks, yaw dampers, cross bracing, or additional friction wedges, to be added to a standard 3-piece truck. The resulting truck system described herein can improve the life of the wheelsets, maintain a high hunting threshold, improve the durability of the pad system, and minimize wear and forces exerted on the rails. By way of background, there are many different rail car types and services native to the North American Rail Industry which require different truck sizes. Cars designed for 70 ton service have a Gross Rail Load of 220,000 lbs., and commonly use 28 inch or 33 inch wheels with 6 inch×11 inch bearings. Cars designed for 100 ton service have a Gross Rail Load of 263,000 lbs., and commonly use 36 inch wheels with 6.5 inch×12 inch bearings. Cars designed for 110 ton service have a Gross Rail Load of 286,000 lbs. and must meet the performance specification M-976 as mentioned above. These 110 ton cars typically use 36 inch wheels with 6.5 inch×9 inch bearings. The final car type typical to North America is designed for 125 ton service and has a Gross Rail Load of 315,000 lbs. This car type typically uses 38 inch wheels with 7 inch×12 inch bearings. The other truck sizes—70 ton, 100 ton, and 125 ton are not subject to the same strict performance standard, and thus have not required the use of pads to date. The roller bearing adapter and matching adapter pad are the focus of this application. Embodiments of the disclosed adapter and matching adapter pad system can be used with cars designed for 110 ton service and can be scalable for use with and improve the performance of trucks for all car capacities (including 70 ton, 100 ton, 110 ton, and 125 ton), including those trucks that do not require compliance with the M-976 standard. One embodiment of the adapter pad system 198 is shown in at least FIGS. 2 and 3. The adapter pad system 198 may comprise a roller bearing adapter 199 and an adapter pad 200 configured to be disposed between a wheelset roller bearing or roller bearing 5 and a side frame pedestal roof 152 of a three-piece railcar truck. The side frame can include first and second outer sides 154, 156. The adapter pad 200 also includes an elastomeric member 360 that supports the vertical load and allows for low force longitudinal, lateral, and rotational motion of the top plate 220 (engaged with the side frame) relative to the bottom plate 240 (engaged with the roller bearing adapter) as compared to a traditional steel-steel sliding adapter system. In some embodiments, as shown in at least FIGS. 2-3, the adapter pad system 198, when installed within a truck system is compressed with a constant vertical load, due to the weight of the railcar and truck components that are carried by the adapter pad 200 and ultimately transferred to the track through the wheel sets. While the vertical load that is imparted upon the central portion of the adapter pad 200 naturally varies with the different loading of the railcar, it has been assumed that a vertical load can be about 35,000 pounds per adapter pad for about a corresponding 286,000 gross rail load car. It has been determined through testing that the performance of the truck system is highly influenced by the stiffness of the adapter pad 200. More specifically, in certain embodiments, it has been determined that truck performance can be improved with improved adapter pad system performance. The adapter pad system performance can be improved by increasing the stiffness of the adapter pad system 198 (measured in pounds of force per inch of displacement). Additionally, for example, it has been determined that acceptable life expectancy (measured in distance traveled under load of a truck system that includes an adapter pad 200 installed, which a design life has been determined to be 1 million miles of railcar travel) is expected for an adapter pad 200 like embodiments discussed herein when a longitudinal stiffness is at least 45,000 pounds per inch or in the range of about 45,000 pounds per inch to about 80,000 pounds per inch, and/or when a lateral stiffness is at least 45,000 pounds per inch or in the range of about 45,000 pounds per inch to about 80,000 pounds per inch, and/or when a rotational stiffness (i.e. stiffness to resist rotation about the vertical axis) is at least 250,000 pound*inches per radian or in the range of about 250,000 pound*inches per radian to about 840,000 pound*inches per radian (each of these measured when a 35,000 pound vertical load is applied to the central portion of the adapter 200). These unique stiffness combinations can maximize the hunting threshold speed, while still maintaining a curve resistance below 0.40 lbs/ton/degree of curvature as required by the M-976 specification without the use of premium truck technologies utilizing transoms, frame bracing, steering arms, spring planks, yaw dampers, cross bracing, or additional friction wedges to improve performance. Stiffness of the adapter pad system is quantified by measuring the adapter assembly resistance to relative shear displacement of the top plate (which is engaged with the side frame), and the bottom plate (which is engaged with the roller bearing adapter). To determine the stiffness, the adapter assembly can be displaced relative to the side frame in multiple directions, such as, longitudinal (in the direction of railcar travel), lateral (across the rail tracks), yaw (rotation about a vertical axis and in line with axle center line), and vertical (between side frame pedestal roof and adapter pad top surface). A vertical load of 35,000 should be maintained during shear stiffness testing to simulate a loaded car scenario. During testing, the force to displace the top plate relative to the bottom plate can be measured using load cells attached to a force actuator. Displacement measurements can be collected with displacement transducers, dial indicators, potentiometers, or other displacement measuring instruments. As described in more detail below, the force and displacement is plotted, with the slope of the hysteresis loop indicating the stiffness in the respective direction. The area contained within the loop is proportional to the energy displaced during the load cycle. Embodiments of the adapter pad system 198 described herein provide a thrust lug opening width and spacing sufficient to not limit displacement within the AAR values, even with the use of high stiffness shear pads as described herein. The disclosed adapter design may utilize target adapter displacements shown in Table 1 below. TABLE 1 AAR ADAPTER TO SIDE FRAME CLEARANCE STACKUP NEW COMPONENTS Features Nominal Maximun Minimun Longitudinal Clearance .047 .139 .017 (Each direction from center: in.) Lateral Clearance .156 .234 .126 (Each direction from center: in.) Rotataional Clearance 26.1 41.0 9.2 (Each direction from center: mRad.) Disclosed embodiments of the adapter pad system 198 with the disclosed longitudinal, lateral, and rotational shear stiffness as described herein can provide an advantageous combination of high speed stability and low curve resistance for the 3-piece truck system. Disclosed embodiments of the adapter pad system 198 can increase the warp restraint of the 3-piece truck system as compared to other adapter pad designs. This can allow for increased high speed stability. In addition to improvements in high speed stability, embodiments of the adapter pad system 198 described herein can promote longitudinal displacement of the wheelset during curving, allowing the leading and trailing axle of the truck assembly to develop an inter-axle yaw angle proportional to the curve which can lower wheelset forces. In combination, the adapter pad system 198 promotes lateral wheelset shift to develop an optimal rolling radius difference during curving. The adapter pad system stiffness and displacement ranges disclosed herein can allow for optimal inter-axle yaw angle and lateral wheelset shift, promoting low wheelset force solution through curves. Reduction in curving forces and improved high speed stability can contribute to improvements in wheelset and rail life. Some adapter pad designs utilize multiple elastomer layers to reduce shear strain. These multiple layers can add significant thickness to the adapter system and when used in conventional trucks, raise the height of the car. Raising the height of the car creates issues coupling to other cars, as well as raises the center of gravity. As a result some designs required the use of special, non-conventional side frames to minimize the height difference. Embodiments discussed herein can allow for improved dynamic performance, without requiring the use of special, non-conventional truck components. Embodiments discussed herein can be used with side frames having AAR standard geometry, including AAR standard pedestal geometry and AAR standard thrust lug clearances, as described in the Association of American Railroads Manual of Standards and Recommended Practices, Section SII (Oct. 25, 2010), Specification S-325 (Jun. 11, 2009)—“Side Frame, Narrow Pedestal—Limiting Dimensions” which is incorporated herein by reference. AAR standard pedestal geometry can be described as including nominal longitudinal thrust lug spacing of about 7.25-8.25 inches; nominal thrust lug width of about 3.5-3.75 inches; nominal longitudinal jaw spacing of about 8.88-11.06 inches; and nominal pedestal roof height above the centerline of the axle of about 5.38-6.89 inches. Embodiments of the adapter pad system 198 disclosed herein can be used with existing and/or standard 3 piece truck systems, including truck systems having AAR standard geometry as described in the Association of American Railroads Manual of Standards and Recommended Practices, and more specifically, Section H (Jan. 1, 2012), Specification M-924 (Feb. 1, 2014)—“Journal Roller Bearing Adapters for Freight Cars” which are incorporated herein by reference. AAR standard thrust lug clearance can be found above in Table 1 for new casting manufacturing dimensions. The thrust lug clearance is determined through the distance between the pedestal area and the roller bearing adapter openings. Standard AAR adapter dimensions can include nominal longitudinal thrust lug bearing surface spacing of about 7.156-8.656 inches; and a nominal lateral thrust lug opening of about 3.812-4.062 inches. Embodiments of the adapter pad system 198 described herein can also meet American Association of Railroads (“AAR”) M-976 specification (AAR Manual of Standards and Recommended Practices, Section D (Sep. 1, 2010), Specification M-976 (Dec. 19, 2013)—“Truck Performance for Rail Cars”) which is incorporated herein by reference. For example, embodiments of the adapter pad system 198 can be used in existing and/or standard 3 piece truck systems without the use of additional pieces such as transoms, frame braces, or spring planks. Additionally, for example, adapter pad systems 198 disclosed herein can fit between the roller bearing 5 and the pedestal roof 152 of existing trucks. Thus, adapter pad systems 198 disclosed herein can have a total height measured between an upper surface of the roller bearing 5 and the pedestal roof 152 of about 1.3 inches or in the range of about 1.1 inches to about 1.5 inches. While the embodiments described herein are specific to the 110T truck, the disclosed adapter and matching adapter pad system can be scalable for use with and improve the performance of trucks for all car capacities (70 ton, 100 ton, 110 ton, and 125 ton), including those trucks that do not require compliance with the M-976 standard. A roller bearing adapter 198 in accordance with the present disclosure is shown in FIGS. 4-10. As shown in FIG. 4, the roller bearing adapter 199 includes a pedestal crown surface 102. The pedestal crown surface or top surface 102 can in some embodiments be a crowned or curved surface such that the central area of the pedestal crown surface is higher than the lateral edges. Thus, the pedestal crown surface 102 can be generally flat in the longitudinal direction and curved in the lateral direction. The pedestal crown surface 102 can be an AAR standard pedestal crown surface but can have a thinner cross-sectional thickness than a typical roller bearing adapter. For example, in some embodiments, the roller bearing adapter thickness can be between about 0.6 inches thick (measured from the bearing surface 117 to the pedestal crown surface 102 at the centerline) to about 0.75 inches thick and in some embodiments less than about 0.75 inches thick. As shown in FIGS. 4-8 the roller bearing adapter 199 can have an overall height of about 4.83 inches or within the range of about 4 inches to about 6 inches; an overall length of about 9.97 inches or in the range of about 9 inches to about 11 inches; and an overall width of about 10 inches or at least 7.5 inches or in the range of about 9 inches to about 11 inches. The roller bearing adapter 199 can include features to limit the motion of the adapter pad 200 relative to the roller bearing adapter 199. For example, the roller bearing adapter can include longitudinal adapter pad stops 104. As shown in FIG. 4, the longitudinal pad stops 104 can be raised vertically relative to the lateral edges of the pedestal crown surface 102. The longitudinal adapter pad stops 104 are designed to interface with slots, recesses, or edges of the bottom plate 240 of the adapter pad 200 and can engage the adapter pad 200 such that the longitudinal motion of the adapter pad 200 can be restricted or controlled to a specified value while not restricting the lateral movement of the adapter pad. Although four longitudinal adapter pad stops 104 are shown in FIG. 4, any number or design of longitudinal pad stops can be used, including continuous longitudinal pad stops that extend the entire length of the lateral edge of the pedestal crown surface 102. Examples of other possible longitudinal stops 104 are shown in FIGS. 5A-5D. For example, the longitudinal stops 104 can comprise two bosses per lateral side as shown in FIG. 5A. The longitudinal stops 104 shown in FIG. 5A can interface with reliefs in the bottom plate 240 of the adapter pad 200 that can engage these stops 104 such that the longitudinal motion can be restricted. Similar to FIG. 5A, FIG. 5B shows three stops 104 that can restrain the longitudinal movement of the adapter pad 200 relative to the adapter 199 in the same way. Longitudinal stops can be incorporated into other portions of the adapter pad. For example, as shown in FIGS. 5C and 5D, longitudinal stops 104 can be incorporated into the top surface of the vertical shoulder 106. Similarly, in these examples, reliefs in the bottom plate 240 of the adapter pad can fit around these stops 104 or bosses and provide longitudinal movement restraint of the bottom plate 240 relative to the top plate 220. Various other combinations of sizes, shapes, and locations can be utilized for the longitudinal stops 104 in order to provide the desired restraint of movement. As shown in FIGS. 4-8, the roller bearing adapter 199 also includes vertical shoulders 106. The vertical shoulders 106 can be raised vertically relative to the longitudinal edges of the pedestal crown surface 102. The vertical shoulders 106 are designed to improve the bending strength of the adapter 199 and minimize distortion of the adapter 199 under the high forces imparted by the adapter pad 200. By minimizing distortion of the adapter pad 200 under load, the vertical shoulders 106 can improve the load distribution to the roller bearing components and can improve bearing life. The vertical shoulders 106 are designed to interface with slots, recesses, edges, or surfaces of the bottom plate 240 of the adapter pad 200 such that the lateral motion of the bottom plate 240 is restricted or controlled to a specified value. In addition to limiting movement of the bottom plate, the vertical shoulders can provide vertical support to the laterally projecting flanges 116, 118 of the adapter pad 200 in some embodiments. The vertical shoulders 106 can extend laterally to 10 inches wide for a 6.5 inch×9 inch adapter, and vertically about 1 inch above the standard pedestal crown surface. In some embodiments the upper surface of the vertical shoulders 106 can be up to about 0.75 inch or up to about 3 inches above the pedestal crown surface 102. The vertical shoulders may also be up to about 8 inches in the longitudinal direction. The vertical shoulders may be cast integral to the adapter, and used on standard adapters for 70T, 100T, 110T, or 125T service. Although continuous vertical shoulders are shown, any number of vertical shoulders can be used. The width of the vertical shoulders can be at least 0.5 inches. The roller bearing adapter 199 can also include features, such as the vertical shoulders 106, to improve the bending strength or cross-sectional moment of inertia of the adapter 199 to minimize distortion of the adapter 199 under the high forces imparted by the adapter pad 200. For example, for the embodiment shown in FIGS. 4, and 6-10, and more particularly shown in FIGS. 8 and 10, a cross-section of the adapter 199 can be taken approximately through the longitudinal center of the roller bearing adapter 199 as shown in FIGS. 8 and 10. As shown in FIG. 10, a neutral Y-axis 108 can extend in the vertical direction through the lateral center of the adapter 199. A neutral Z-axis 110 can extend in the lateral direction about 5.2 inches, or in the range of about 5.0 inches and 5.5, above a center axis of an axle 111. The cross-sectional moment of inertia of the cross-section shown in FIG. 10 around the neutral Z-axis 110, I z-z, at the center of the adapter can be about 1.4 in4, or in the range of about 1.0 to about 2.0 in4. The cross-sectional moment of inertia around the neutral Y-axis 108 at the center of the adapter, I y-y at the cross-section can be about can be about 86.8 in4, or in the range of about 50 to about 100 in4. Adapter designs which do not utilize vertical shoulders have significantly lower area moment of inertia through lateral sections. For example, an adapter design as shown in FIG. 10 but without vertical shoulders 106 at the same lateral centerline cross section can have a moment of inertia around the neutral Z-axis of about 0.2 in4 and can have a moment of inertia around the neutral Y-axis of about 32.9 in4. The resulting lower moment of inertia compared to the disclosed adapter can result in a lower stiffness and higher stresses in the adapter under similar load configurations, and possibly reduced roller bearing performance. The roller bearing adapter 199 may be made from one or more different types of alloys of steel that have suitable strength and other performance characteristics. For example, roller bearing adapter 199 may be manufactured from cast iron of grade ASTM A-220, A-536,
{'app_number': None, 'application_number': '<application-reference appl-type="utility">\n<document-id>\n<country>US</country>\n<doc-number>14585569</doc-number>\n<date>20141230</date>\n</document-id>\n</application-reference>', 'doc_number': None, 'publication_number': '<publication-reference>\n<document-id>\n<country>US</country>\n<doc-number>20150183442</doc-number>\n<kind>A1</kind>\n<date>20150702</date>\n</document-id>\n</publication-reference>', 'source_file': './application/2015/ipa150702.xml', 'source_data': 'USPTO-Application'}