[001] This disclosure relates generally to a rear underrun protective device (RUPD) for a vehicle, and more particularly to a light weight L-shaped RUPD for a vehicle.

BACKGROUND
[002] Heavy-duty vehicles, such as trucks, trailers, loader vehicles, and oth\er commercial vehicles may be deigned to carry a payload of more than one tonnage, and have greater height as compared to vehicles of other segments like passenger vehicles. These heavy-duty vehicles are required to unload and load the payload from a specific height, for example, at a ramp constructed at the docking place. Due to high load carrying capacity, these heavy-duty vehicles may require a higher suspension design which causes the height of the vehicle to increase. Further, for maximum utilization of the space inside such a heavy-duty vehicle, the floor may be constructed in a flatbed configuration to enable proper positioning of the transmission system. Furthermore, for equivalent and efficient distribution and transfer of the load to the ground and for proper traction, the tires used in these heavy-duty vehicles may have large diameter and width. However, as a result of the above factors, there may be a wider gap between the floor and the ground surface.
[003] In a situation of rear impact, for example, impact by a passenger vehicle from the rear side of the heavy-duty vehicle, the gap may allow the impacting vehicle to penetrate under the chassis of the heavy-duty vehicle, thereby leading to causing greater damage to the impacting vehicle and the heavy-duty vehicle. To avoid or minimize such damage, the heavy-duty vehicle may be equipped with a rear underrun protective device (RUPD). The RUPD may be provided on the chassis of heavy-duty vehicle. Various geometries and designs of the RUPDs may be possible. For example, some designs may include steel-based closed cross-section members welded together in a pie-shape geometry. It should be noted that the design of the RUPD should comply with the standards set forth by global or country-specific standard setting authorities. For example, one such standard is IS 14812 (2005) that specifies general requirements of the RUPD.
[004] As it will be appreciated by those skilled in the art, the geometry of the RUPD, once damaged, cannot be changed without the use of heavy machinery. Further, the weight-to-strength ratio of the geometry lacks modularity. Furthermore, the welding is limited to some specific metals and is not feasible for other metals like aluminum which is lighter. For example, Aluminum may be weldable using specific welding techniques like Tungsten Inert Gas (TIG) welding; however, these techniques prove expensive. Moreover, strength of welding on Aluminum based material decreases with welding.
[005] In case of impact on the extremities of the RUPD, the steel-based crash beam part of the RUPD may fail due to insufficient inertial load bearing capacity. It should be noted that even when the ends of the RUPD are reinforced, for same cross-section, the steel-based RUPD will have lesser strain elongation than aluminum-based RUPD.
[006] Therefore, a RUPD is desired that has ability to effectively stop an impacting body from penetrating the vehicle underbelly, has high impact absorption capacity, optimum weight to strength ratio, is compliant with the mandatory design requirements.

SUMMARY
[007] In one embodiment, a rear underrun protective device (RUPD) for a vehicle is disclosed. The RUPD may include a pair of first members. Each of the pair of first members may be configured to be coupled to the vehicle via a top portion of each of the pair of first members. Further, each of the pair of first members may be configured to be coupled to the vehicle in substantially vertical orientation of each of the pair of first members. The RUPD may further include a pair of connecting members. Each of the pair of connecting members may be configured to be coupled to a respective first member of the pair of first members via a bottom portion of the respective first member of the pair of first members and via a front portion of each of the pair of connecting members. Further, each of the pair of connecting members may be configured to be coupled to a respective first member of the pair of first members in a substantially horizontal orientation of each of the pair of connecting members. The RUPD may further include a crash-beam member configured to be coupled to each of the pair of connecting members via a rear portion of each of the pair of connecting members in a substantially horizontal configuration of the crash-beam member, and substantially perpendicular to each of the pair of connecting members. At least one of: the pair of first members, the pair of connecting members, and the crash-beam member may include comprises a plurality of respective sub-members stacked into each other.
[008] In another embodiment, a vehicle is disclosed. The vehicle includes a chassis. The vehicle may further include a rear underrun protective device coupled to the chassis. The RUPD may include a pair of first members. Each of the pair of first members may be configured to be coupled to the vehicle via a top portion of each of the pair of first members. Further, each of the pair of first members may be configured to be coupled to the vehicle in substantially vertical orientation of each of the pair of first members. The RUPD may further include a pair of connecting members. Each of the pair of connecting members may be configured to be coupled to a respective first member of the pair of first members via a bottom portion of the respective first member of the pair of first members and via a front portion of each of the pair of connecting members. Further, each of the pair of connecting members may be configured to be coupled to a respective first member of the pair of first members in a substantially horizontal orientation of each of the pair of connecting members. The RUPD may further include a crash-beam member configured to be coupled to each of the pair of connecting members via a rear portion of each of the pair of connecting members in a substantially horizontal configuration of the crash-beam member, and substantially perpendicular to each of the pair of connecting members. At least one of: the pair of first members, the pair of connecting members, and the crash-beam member may include comprises a plurality of respective sub-members stacked into each other.
[009] 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, as claimed.

BRIEF DESCRIPTION OF THE DRAWINGS
[010] The accompanying drawings, which are incorporated in and constitute a part of this disclosure, illustrate exemplary embodiments and, together with the description, explain the disclosed principles.
[011] FIG. 1A illustrates a perspective view of the rear underrun protective device (RUPD) for a vehicle, in accordance with an embodiment of the present disclosure.
[012] FIG. 1B illustrates a front view of the RUPD for a vehicle, in accordance with an embodiment of the present disclosure.
[013] FIG. 1C illustrates a side view of the RUPD for a vehicle, in accordance with an embodiment of the present disclosure.
[014] FIG. 1B illustrates a top view of the RUPD for a vehicle, in accordance with an embodiment of the present disclosure.
[015] FIG. 2 illustrates a perspective view of an unassembled RUPD for a vehicle, in accordance with an embodiment of the present disclosure.
[016] FIGS. 3A-B illustrate perspective views of a vehicle, in accordance with some embodiments of the present disclosure.
[017] FIG. 4 illustrates a graph showing comparison of reaction force on node developed in a RUPD of the present disclosure and a conventional RUPD made using single members
[018] FIG. 5 illustrates a graph showing comparison of internal energy developed in the RUPD of the above disclosure and a conventional RUPD made using single members.
[019] FIG. 6A shows a visual from simulation study of the RUPD of the above disclosure made using plurality of sub-members, showing location of deformation points under loading condition.
[020] FIG. 6B illustrates a visual from simulation study of the RUPD of the above disclosure made using plurality of sub-members, showing location of high strain points under loading condition.
[021] FIG. 6C illustrates a visual from simulation study of the RUPD of the above disclosure made using plurality of sub-members, showing location of high stress points under loading condition.
[022] FIG. 7 illustrates a flowchart of a method of assembling the RUPD, in accordance with some embodiments of the present disclosure.

DETAILED DESCRIPTION
[023] Exemplary embodiments are described with reference to the accompanying drawings. Wherever convenient, the same reference numbers are used throughout the drawings to refer to the same or like parts. While examples and features of disclosed principles are described herein, modifications, adaptations, and other implementations are possible without departing from the spirit and scope of the disclosed embodiments. It is intended that the following detailed description be considered as exemplary only, with the true scope and spirit being indicated by the following claims. Additional illustrative embodiments are listed below.
[024] Referring to FIGS. 1A-D, different views of a rear underrun protective device (RUPD) 100 for a vehicle are illustrated in accordance with some embodiments of the present disclosure. FIG. 1A illustrates a perspective view of the RUPD 100 for a vehicle. FIG. 1B illustrates a front view of the RUPD 100 for a vehicle. FIG. 1C illustrates a side view of the RUPD 100 for a vehicle. FIG. 1D illustrates a top view of the RUPD 100 for a vehicle. In some embodiments, the RUPD 100 may be implemented in a heavy-duty vehicle (not shown in FIGS. 1A-D), like a truck, a trailer, etc.
[025] As shown in FIGS. 1A-D, in some embodiments, the RUPD 100 may include a pair of first members 102A, 102B (hereinafter, collectively referred to as pair of first members 102, or simply, first members 102). For example, the pair of first members 102 may include a left first member 102A and a right first member 102B. In some embodiments, each of the pair of first members 102 may be configured to be coupled to the vehicle via a top portion of each of the pair of first members 102. For example, the left first member 102A may be configured to be coupled to the vehicle via a top portion 102A(t) of the left first member 102A. Similarly, the right first member 102B may be configured to be coupled to the vehicle via a top portion 102B(t) of the right first members 102B.
[026] In some embodiments, each of the pair of first members 102 may be further configured to be coupled to the vehicle in substantially vertical orientation of each of the pair of first members 102. As shown in the FIGS. 1A-C, the left first member 102A may be configured to be coupled to the vehicle in substantially vertical orientation of the left first member 102A, and the right first member 102B may be configured to be coupled to the vehicle in substantially vertical orientation of the right first member 102B.
[027] The RUPD 100 may further include a pair of connecting members 104A, 104B (hereinafter, collectively referred to as pair of connecting members 104, or simply, connecting members 104). For example, the pair of connecting members 104 may include a left connecting member 104A and a right connecting member 104B. In some embodiments each of the pair of connecting members 104 may be configured to be coupled to a respective first member of the pair of first members 102 via a bottom portion of the respective first member of the pair of first members 102 and via a front portion of each of the pair of connecting members 104.
[028] For example, as shown in FIG. 1C, the left connecting member 104A may be configured to be coupled to the left first member 102A via a bottom portion 102A(b) of the left first member 102A and via a front portion 104A(f) of the left connecting members 104A. Similarly, the right connecting member 104B may be configured to be coupled to the right first member 102B via a bottom portion 102B(b) of the right first member 102B and via a front portion 104B(f) of the right connecting member 104B.
[029] It may be noted that each of the pair of connecting members 104 may be further configured to be coupled to a respective first member of the pair of first members 102 in a substantially horizontal orientation of each of the pair of connecting members 104. For example, the left connecting member 104A may be configured to be coupled to the left first member 102A in a substantially horizontal orientation of the left connecting member 104A. Similarly, the right connecting member 104B may be configured to be coupled to the right first member 102B in a substantially horizontal orientation of the right connecting member 104B.
[030] The RUPD 100 may further include a crash-beam member 106. The crash-beam member 106 may be configured to be coupled to each of the pair of connecting members 104 via a rear portion of each of the pair of connecting members 104. For example, as shown in FIG. 1D, the crash-beam member 106 may be configured to be coupled to the left connecting member 104A via a rear portion 104A(r) of the left connecting member 104A. Similarly, the crash-beam member 106 may be configured to be coupled to the right connecting member 104B via a rear portion 104B(r) of the right connecting member 104B.
[031] In some embodiments, the crash-beam member 106 may be configured to be coupled to each of the pair of connecting members 104 in a substantially horizontal configuration of the crash-beam member 106, and substantially perpendicular to each of the pair of connecting members 104. As such, the crash-beam member 106 may be configured to be coupled to the left connecting member 104A in a substantially horizontal configuration of the crash-beam member 106 and substantially perpendicular to the left connecting member 104A. Similarly, the crash-beam member 106 may be configured to be coupled to the right connecting member 104B in a substantially horizontal configuration of the crash-beam member 106 and substantially perpendicular to the right connecting member 104B.
[032] As shown in FIG. 1C, by way of the above configuration of the RUPD 100, the RUPD 100 may have an L-shaped configuration, having a vertically oriented leg and a horizontally oriented leg. The pair of first members 102 may form the vertically oriented leg, and the pair of connecting members 104 and the crash-beam member 106 may form the horizontally oriented leg of the L-shaped RUPD 100.
[033] As mentioned earlier, each first member of the pair of first members 102 may be configured to be coupled to the vehicle. In some embodiments, each first member of the pair of first members 102 may be configured to be coupled to the vehicle using one or more fastening members. In other words, the left first member 102A may be configured to be coupled to the vehicle using one or more fasteners. Similarly, the right first member 102B may be configured to be coupled to the vehicle using one or more fasteners. In some embodiments, these one or more fasteners may include one or more bolts, or one or more not-bolt assemblies, or one or more rivets. It may be noted that the bolts may be dimensioned and patterned according to their shear capacity, in compliance with shear from loading condition as prescribed in “IS 14812” standards. For example, the left first member 102A may be coupled to the vehicle using a minimum of nine ‘M12’ bolts. Similarly, the right first member 102B may be coupled to the vehicle using a minimum of nine ‘M12’ bolts.
[034] Therefore, the left first member 102A and the right first member 102B may be removable from the vehicle from and re-installable on the vehicle, by using the one or more fasteners.
[035] In some embodiments, each of the pair of connecting members 104 may be configured to be coupled to a respective first member of the pair of first members 102 using one or more fasteners. In particular, the left connecting member 104A and the right connecting member 104B may be configured to be coupled to the left first member 102A and the right first member 102B, respectively, using the one or more fasteners. In some embodiments, these one or more fasteners may include one or more bolts, or one or more not-bolt assemblies, or one or more rivets. In other words, the each connecting member of the pair of connecting members 104 may be removable from and re-installable on the respective first member of the pair of first members 102, using one or more fasteners.
[036] In some embodiments, each connecting member of the pair of connecting members 104 may be configured to be coupled to a respective first member of the pair of first members 102 via one or more shear clips 108. For example, the left connecting member 104A may be configured to be coupled to the left first member 102A via one or more left shear clips 108A (the one or more left shear clips individually or collectively are referred to as left shear clip(s) 108A). Similarly, the right connecting member 104B may be configured to be coupled to the right first member 102B via one or more right shear clips 108B (the one or more right shear clips individually or collectively are referred to as right shear clip(s) 108B).
[037] In some embodiments, each of the one or more left shear clips 108A or the one or more right shear clips 108B may be L-shaped having two legs aligned at 90 degrees to each other. Further, one leg of the shear clip may be configured to be coupled to the respective first member, and the other leg of the shear clip may be configured to be coupled to the respective connecting member.
[038] In some embodiments, each connecting member of the pair of connecting members 104 may be configured to be coupled to a respective first member of the pair of first members 102 via one or more shear clips 108, using the one or more fastening members. As such, each of the one or more shear clips 108 may have one or more holes to allow the fastening members to pass through. For example, the fastening members may include two sets of bolts. A first set of bolts (of the two sets of bolts) may be used to couple (fasten) the shear clip to a respective first member. A second one set of bolts (of the two sets of bolts) may be used to couple the shear clip to a respective connecting member. As a result, the first member may be coupled to the respective connecting member via the shear clips. For example, each connecting member may be coupled to a respective first member via a minimum of two shear clips 108, each using one or more fastening members. Further, for example, each of the first set of bolts and the second set of bolts may include a minimum of two ‘M8’ bolts.
[039] In some embodiments, the shear clips 108 may be made from aluminum-based alloy. For example, the shear clips 108 may be made from aluminum ‘6061 T6’ alloy or aluminum ‘6062 T6’ alloy. However, the material of the shear clips 108 may not be restricted to the aluminum-based alloys, and may include any other metal as well.
[040] In some embodiments, each connecting member of the pair of connecting member 104 may be further configured to be coupled to a respective first member of the pair of first members 102 via one or more vertical gusset plates 110. For example, the left connecting member 104A may be configured to be coupled to the left first member 102A via one or more left vertical gusset plates 110A (the one or more left vertical gusset plates individually or collectively are referred to as left vertical gusset plate(s) 110A). Similarly, the right connecting member 104B may be configured to be coupled to the right first member 102B via one or more right vertical gusset plates 110B (the one or more right vertical gusset plates individually or collectively are referred to as right vertical gusset plate(s) 110B).
[041] In some embodiments, each of the one or more left vertical gusset plates 110A or the one or more right vertical gusset plates 110B may be triangular-shaped having a flat body. For example, one corner of the vertical gusset plate may be configured to be coupled to the respective first member, and the other corner of the vertical gusset plates may be configured to be coupled to the respective connecting member.
[042] In some embodiments, each connecting member of the pair of connecting members 104 may be configured to be coupled to a respective first member of the pair of first members 102 via one or more vertical gusset plates 110, using one or more fastening members. As such, each of the one or more vertical gusset plates 110 may have one or more holes to allow the fastening members to pass through. For example, the fastening members may include two sets of bolts. Further, a first set of bolts (of the two sets of bolts) may be used to couple (fasten) the vertical gusset plate to a respective first member. A second one set of bolts (of the two sets of bolts) may be used to couple the vertical gusset plate to a respective connecting member. As a result, the first member may be coupled to the respective connecting member via the vertical gusset plates.
[043] In some embodiments, the vertical gusset plates 110 may be made from aluminum-based alloy. For example, the vertical gusset plates 110 may be made from aluminum 6061 T6 alloy. However, the material of the vertical gusset plates 110 may not be restricted to the aluminum-based alloys, and may include any other metal as well.
[044] As mentioned above, the crash-beam member 106 may be configured to be coupled to each of the pair of connecting members 104. In some embodiments, the crash-beam member 106 may be configured to be coupled to each connecting member of the pair of connecting members 104 via one or more horizontal gusset plates 112. For example, the left connecting member 104A may be configured to be coupled to the crash-beam member 106 via one or more left horizontal gusset plates 112A (the one or more left horizontal gusset plates individually or collectively are referred to as 112A). Similarly, the right connecting member 104B may be configured to be coupled to the crash-beam member 106 via one or more right horizontal gusset plates 112B (the one or more right horizontal gusset plates individually or collectively are referred to as 112B).
[045] In some embodiments, each of the one or more left horizontal gusset plates 112A or the one or more right horizontal gusset plates 112B may be triangular-shaped having a flat body. For example, one corner of the horizontal gusset plate may be configured to be coupled to the crash-beam member 106, and the other corner of the gusset plates may be configured to be coupled to the respective connecting member.
[046] In some embodiments, as shown in the FIG. 1C, the crash-beam member 106 may be configured to be further coupled to each connecting member of the pair of connecting members 104 via one or more shear clips 114. Each of the one or more one or more shear clips 114 may be aligned along the sides of the crash-beam member 106 and the sides of each connecting member of the pair of connecting members 104. As such, each of the one or more one or more shear clips 114 may be L-shaped (i.e. two legs inclined substantially perpendicular to each other), such that one leg of the of the shear clip 114 is coupled to the crash-beam member 106 and the other leg is coupled to a connecting member of the pair of connecting members 104.
[047] In some embodiments, the crash-beam member 106 may be configured to be coupled to a respective connecting member of the pair of connecting members 104 via one or more horizontal gusset plates 112, using one or more fastening members. As such, each of the one or more horizontal gusset plates 112 may have one or more holes to allow the fastening members to pass through. For example, the fastening members may include two sets of bolts. Further, a first set of bolts (of the two sets of bolts) may be used to couple (fasten) the horizontal gusset plate to the crash-beam member 106. A second one set of bolts (of the two sets of bolts) may be used to couple the horizontal gusset plate to a respective connecting member. As a result, the crash-beam member 106 may be coupled to the connecting members 104 via the horizontal gusset plates.
[048] In some embodiments, the horizontal gusset plates 112 may be made from aluminum-based alloy. For example, the horizontal gusset plates 112 may be made from aluminum 6061 T6 alloy. However, the material of the horizontal gusset plates 112 may not be restricted to the aluminum-based alloys, and may include any other metal as well.
[049] It may be understood that the shear clips 108, the vertical gusset plates 110, and the horizontal gusset plates 112 may transfer the shear and axial load from the point of impactor to the chassis of the vehicle.
[050] Referring now to FIG. 2, a perspective view of an unassembled rear underrun protective device (RUPD) 100 for a vehicle illustrated in accordance with another embodiment of the present disclosure. In some embodiments, the RUPD 100 may be implemented in a heavy-duty vehicle (not shown in FIG. 1), like a truck, a trailer, etc.
[051] As shown in the FIG. 2, the RUPD 100 may include the pair of first members 102A, 102B (also, collectively referred to as pair of first members 102, or simply first members 102). For example, the pair of first members 102 may include a left first member 102A and a right first member 102B. Each of the pair of first members 102, i.e., the left first member 102A and the right first member 102 may be configured to be coupled to the vehicle via a top portion of each of the pair of first members 102, in substantially vertical orientation of each of the pair of first members 102.
[052] In some embodiments, each of the pair of first members 102 may include a plurality of first sub-members, such that the plurality of first sub-members is configured to be stacked into each other. In other words, the left first member 102A may include a plurality of left first sub-members 202A. Similarly, the right first member 102B may include a plurality of right first sub-members 202B. The plurality of left first sub-members 202A and the plurality of right first sub-members 202B may be collectively referred to as plurality of first sub-members 202. The plurality of first sub-members 202 (i.e., 202A, 202B) may be configured to be stacked into each other. In other words, the each of the pair of first members 102 may be formed by stacking together into each other the plurality of first sub-members.
[053] In some embodiments, the plurality of left first sub-members 202A may be stacked together and then fastened together using one or more fasteners. Similarly, the plurality of right first sub-members 202B may be stacked together and then fastened together using one or more fasteners. For example, the one or more fasteners may include one or more bolts, or one or more not-bolt assemblies, or one or more rivets.
[054] As mentioned earlier, each of the pair of first members 102 may be configured to be coupled to the vehicle using one or more fastening members. In some embodiments, the plurality of left first sub-members 202A may be stacked and fastened together to form each of the pair of first members 102, and then the pair of first members 102 may be coupled to the vehicle using the one or more fastening members.
[055] In some embodiments, as shown in FIG. 2, each of the plurality of first sub-members 202A, 202B may have a C-shaped section (cross section). In other words, each of the plurality of first sub-members 202 may have one web and two flange configuration. In some embodiments, thickness of each of the plurality of first sub-members 202 may be 2.5 millimeters (mm). In some embodiments, three first sub-members 202 may be used to form a first member (i.e., the left first member 102A or the right first member 102B). As such, the thickness of the first member may be 7.5 mm. In some embodiments, each of the plurality of first sub-members 202 may be manufactured from a sheet made of a metal having a thickness of 2.5 mm. Further, the width (width of the web) of each sub-member of the plurality of left first sub-member 202A or the plurality of right first sub-member 202B may vary from each other, to allow the other sub-members to be stacked into each other.
[056] As mentioned earlier, the RUPD 100 may further include a pair of connecting members 104A, 104B (also, collectively referred to as pair of connecting members 104, or simply connecting members 104). For example, the pair of first connecting member 104 may include the left connecting member 104A and the right first connecting member 104B. Each of the pair of connecting member 104, i.e., the left connecting member 104A and the right connecting member 104B may be configured to be coupled to the respective first member of the pair of first members 102 via a bottom portion of the respective first member of the pair of first members and via a front portion of each of the pair of connecting members 104, in a substantially horizontal orientation of each of the pair of connecting members 104.
[057] In some embodiments, each of the pair of connecting members 104 may include a plurality of connecting sub-members, such that the plurality of connecting sub-members may be configured to be stacked into each other. For example, the left connecting member 104A may include a plurality of left connecting sub-members 204A. Similarly, the right connecting member 104B may include a plurality of right connecting sub-members 204B.
[058] The plurality of left connecting sub-members 204A may be configured to be stacked into each other, and the plurality of right connecting sub-members 204B may be configured to be stacked into each other. In other words, the each of the pair of connecting members 104 may be formed by stacking together into each other the respective plurality of first sub-members. The width (width of the web) of each sub-member of the plurality of left connecting sub-member 204A or the plurality of right connecting sub-member 204B may vary from each other, to allow the other sub-members to be stacked into each other.
[059] In some embodiments, the plurality of left connecting sub-members 204A may be stacked together and then fastened together using one or more fasteners. Similarly, the plurality of right connecting sub-members 204B may be stacked together and then fastened together using one or more fasteners. For example, the one or more fasteners may include one or more bolts, or one or more not-bolt assemblies, or one or more rivets.
[060] In some embodiments, as shown in FIG. 2, each of the plurality of connecting sub-members 204 (i.e., 204A, 204B) may have a C-shaped section (cross section). In other words, each of the plurality of connecting sub-members 204 may have one web and two flange configuration. In some embodiments, thickness of each of the plurality of connecting sub-members 204 may be 2.5 millimeters (mm). In some embodiments, each of the plurality of connecting sub-members 204 may be manufactured from a metal sheet having a thickness of 2.5 mm.
[061] As mentioned earlier, the RUPD 100 may further include the crash-beam member 106 configured to be coupled to each of the pair of connecting members 104 via the rear portion of each of the pair of connecting members 104 in a substantially horizontal configuration of the crash-beam member 106, and substantially perpendicular to each of the pair of connecting members 104.
[062] In some embodiments, the crash-beam member 106 may include a plurality of crash-beam sub-members 206, such that the plurality of crash-beam sub-members may be configured to be stacked into each other. The plurality of crash-beam sub-members 206 may be configured to be stacked into each other. In other words, the crash-beam member 106 may be formed by stacking together into each other the respective plurality of crash-beam sub-members 206.
[063] In some embodiments, the plurality of crash-beam sub-members 206 may be stacked together and then fastened together using one or more fasteners. For example, the one or more fasteners may include one or more bolts, or one or more not-bolt assemblies, or one or more rivets.
[064] In some embodiments, as shown in FIG. 2, each of the plurality of crash-beam sub-members 206 may have a C-shaped section. In other words, each of the plurality of crash-beam sub-members 206 may have one web and two flange configuration. In some embodiments, thickness of each of the plurality of the plurality of crash-beam sub-members 206 may be 2.5 millimeters (mm). In some embodiments, each of the plurality of crash-beam sub-members 206 may be manufactured from a metal sheet having a thickness of 2.5 mm.
[065] In some embodiments, the thickness of each of the plurality of first sub-members 202, each of the plurality of connecting sub-members 204, and each of the plurality of crash-beam sub-members 206is same. For example, the thickness of each of the plurality of first sub-members 202, each of the plurality of connecting sub-members 204, and each of the plurality of crash-beam sub-members 206 is 2.5 milli meters.
[066] The width (width of the web) of each sub-member of the plurality of crash-beam sub-members 206 may vary from each other, to allow the other sub-members to be stacked into each other.
[067] In some embodiments, as shown in FIG. 2, the plurality of crash-beam sub-members may include a plurality of crash-beam bottom sub-members 206(b). In some embodiments, each of the plurality of crash-beam bottom sub-members 206(b) may have the C-shaped section. The plurality of crash-beam sub-members may further include a plurality of crash-beam top sub-members 206(t). In some embodiments, each of the plurality of crash-beam top sub-members 206(t) may have the C-shaped section.
[068] In some embodiments, the plurality of crash-beam top sub-members 206(t) may be configured to be positioned on the plurality of crash-beam bottom sub-members 206(b) in an inverted position relative to the plurality of crash-beam bottom sub-members 206(b), to form a substantially rectangular cross section of the crash-beam member 106.
[069] For example, the plurality of crash-beam bottom sub-members 206(b) may be stacked to form a crash-beam bottom member. Further, the plurality of crash-beam top sub-members 206(t) may be stacked to form a crash-beam top member. The crash-beam top member may be positioned on the crash-beam bottom member in an inverted position relative to the crash-beam bottom member, to form the substantially rectangular cross section of the crash-beam member 106.
[070] By way of an example, the plurality of crash-beam bottom sub-members 206(b) and the plurality of crash-beam top sub-members 206(t) (inverted relative to the plurality of crash-beam bottom sub-members 206(b)) may be stacked and fastened together using rivets to form a crash-beam 106. The crash-beam 106 may then be fastened to the connecting members 104 using bolts.
[071] Referring now to FIGS. 3A-B, perspective views 300A, 300B of a vehicle 300 are illustrated, in accordance with an embodiment of the present disclosure. The vehicle 300 may include a chassis 302. Further, the vehicle 300 may include a rear underrun protective device (RUPD) 100 coupled to the chassis 302.
[072] As already explained in conjunction with FIGS. 1 and 2, the RUPD 100 may include a pair of first members 102A, 102B, each of the pair of first members 102A, 102B configured to be coupled to the chassis 302 via a top portion of each of the pair of first members 102A, 102B. For example, each pair of first members 102 (i.e., the left first member 102A and the right first member 102B) may be coupled to the chassis 302 using eighteen ‘M12’ bolts. Each of the pair of first members 102A, 102B may be further configured to be coupled to the chassis 302 in substantially vertical orientation of each of the pair of first members 102A, 102B. the RUPD 100 may further includes a pair of connecting members 104A, 104B. Each of the pair of connecting members 104A, 104B may be configured to be coupled to a respective first member of the pair of first members 102A, 102B via a bottom portion of the respective first member of the pair of first members 102A, 102B and via a front portion of each of the pair of connecting members 104A, 104B. Each of the pair of connecting members 104A, 104B may be further configured to be coupled to a respective first member of the pair of first members 102A, 102B in a substantially horizontal orientation of each of the pair of connecting members 104A, 104B. The RUPD 100 may further include a crash-beam member 106 configured to be coupled to each of the pair of connecting members 104A, 104B via a rear portion of each of the pair of connecting members 104A, 104B in a substantially horizontal configuration of the crash-beam member 106, and substantially perpendicular to each of the pair of connecting members 104A, 104B.
[073] It may be noted that the at least one of: the pair of first members 102A, 102B, the pair of connecting members 104A, 104B, and the crash-beam member 106 may include a plurality of respective sub-members stacked into each other. This is already explained in conjunction with FIG. 2.
[074] The above disclosure provides for an improved RUPD for a vehicle. The RUPD with the L-shaped configuration provides for effective impact absorption, in case of accidents of heavy-duty vehicles. Further, by implementing a plurality of C-shaped section sub-members stacked into each other in at least one of the pair of first members, the pair of connecting members, and the crash-beam member, a light-weight and high-strength solution for the RUPD is obtained. Further, the above design (i.e., L-shaped configuration of RUPD and stacked plurality of sub-members) allows the different part of the RUPD, i.e., the pair of first members, the pair of connecting members, and the crash-beam member to be made from light-weight materials like Aluminum-based alloys. The Aluminum-based alloy, like the Aluminum 6061 T6 alloy provides for a robust, strong, and durable RUPD. Further, the one web two flange configuration of the C-shaped section sub-members enables three face mounting of the sub-members, which adds to the strength of the assembly of the pair of first members, the pair of connecting members, or the crash-beam member, and therefore of the RUPD. The Aluminum-based structure provides optimum strength-to-weight ratio, which is better than the conventional steel-based or iron-based structures being used in the industry.
[075] Due to simple deign and low thickness (2.5 mm) of the sub-members, the sub-members are easier to manufacture. Further, the manufacturing cost of the sub-members is low due to lighter and lesser expensive dies required for manufacturing the sub-members. As a result, the manufacturing cost of least the pair of first members, or the pair of connecting members, or the crash-beam member, and therefore of the RUPD is brought down. Further, by keeping the thickness of the sub-members low - of about 2.5 mm, the multiple variations in the thickness of the first members, the connecting members, and the crash-beam member can be achieved. This allows for assembling and manufacturing the RUPD of different shapes and sizes using the sub-members for different vehicles or different usages. Further, this allows for varying the inertia of the components (i.e., the first members, the connecting members, and the crash-beam member) in accordance with the moment that will act while loading/impact.
[076] Further, by providing for assembling of the RUPD by fasteners, the RUPD can be easily assembled and unassembled. This allows for easy repairing and maintaining of the RUPD. Moreover, in case of damage to the RUPD, only the damaged components/parts of the RUPD can be removed, and repaired or replaced. This brings down the time, labor, and cost during repairing.
[077] Referring to FIG. 4, a graph 400 showing comparison of reaction force on node developed in a RUPD of the above disclosure made using plurality of sub-members (i.e., plurality of C-section shaped sub-members stacked into each other) and a RUPD made using single members (conventional RUPD). The graph plot line 402 corresponds to the RUPD of the above disclosure made using plurality of sub-members, and the graph plot line 404 corresponds to the RUPD made using single members (conventional RUPD).
[078] Referring to FIG. 5, a graph 500 showing comparison of internal energy developed in a RUPD of the above disclosure made using plurality of sub-members (i.e., plurality of C-section shaped sub-members stacked into each other) and a RUPD made using single members (conventional RUPD) is illustrated. The graph plot line 502 corresponds to the RUPD of the above disclosure made using plurality of sub-members, and the graph plot line 504 corresponds to the RUPD made using single members (conventional RUPD).
[079] Referring to FIG. 6A, a visual 600A from simulation study of the RUPD of the above disclosure made using plurality of sub-members, showing location of deformation points under loading condition is illustrated. The visual 600A corresponds to load conditions as seen in the visual 600A. FIG. 6B illustrates a visual 600B from simulation study of the RUPD of the above disclosure made using plurality of sub-members, showing location of high strain points under loading condition is illustrated. The visual 600B corresponds to load conditions as seen in the visual 600B. It may be noted that plastic strain at locations where the strain is highest is shown via circles. It may be further noted that when the material goes under nonlinear or large deformation, the material exhibits plastic characteristics and in that region of simulation critical areas of interest are identified which paves the path for the reaction force to travel. FIG. 6C illustrates a visual 600C from simulation study of the RUPD of the above disclosure made using plurality of sub-members, showing location of high stress points under loading condition is illustrated. The visual 600C corresponds to load conditions as seen in the visual 600C. The stress is the reaction of the load applied in the dynamic condition. FIG. 6C shows the travel of the reaction load. The locations of high stress areas are encircled. The area with comparatively less inertia than the adjacent geometry is bearing larger stress.
[080] Referring now to FIG. 7, a flowchart of a method 700 of assembling a rear underrun protective device (RUPD) 100 for a vehicle is illustrated, in accordance with an embodiment. At step 702, a plurality of first sub-members 202 may be stacked together. In particular, a plurality of first left sub-members 202A may be stacked together using M12 and M8 bolts on both sides, to form left first member 102A. Similarly, a plurality of right first sub-members 202B may be stacked together using M12 and M8 bolts on both sides, to form the right first member 102B.
[081] At step 704, one or more shear clips may be stacked. In particular, one or more left shear clips 108A may be stacked using M8 bolts on both the sides. Similarly, one or more right shear clips 108B may be stacked using M8 bolts on both the sides. At step 706, one or more vertical gusset plates 110 and horizontal gusset plates 112 may be stacked. In particular, one or more left vertical gusset plates 110A may be stacked together using M8 bolts on both the sides. Similarly, one or more right vertical gusset plates 110B may be stacked together using M8 bolts on both the sides. Further, one or more left horizontal gusset plates 112A may be stacked together using M8 bolts on both the sides. Similarly, one or more right horizontal gusset plates 112B may be stacked together using M8 bolts on both the sides.
[082] At step 708, the plurality of connecting sub-members may be stacked. In particular, the plurality of left connecting sub-members 204A may be stacked together using M8 bolts on both sides, to form the left connecting member 104A. The plurality of right connecting sub-members 204B may be stacked together using M8 bolts on both sides, to form the right connecting member 104B.
[083] At step 710, the first members 102 (obtained at step 702), the shear clips 108, the vertical gusset plates 110, and the horizontal gusset plates 112 may be connected together. In particular, the left first member 102A, the one or more left shear clips 108A, the one or more left vertical gusset plates 110A, and the one or more left horizontal gusset plates 112A may be connected together. Further, the right first member 102B, the one or more right shear clips 108B, the one or more right vertical gusset plates 110B, and the one or more right horizontal gusset plates 112B may be connected together.
[084] At step 712, the plurality of crash beam sub-members 206 may be stacked together and fastened, to obtain the crash beam 106. For example, the plurality of crash beam sub-members 206 may fastened using rivets of size 5 mm (diameter). Further, at step 712, the crash beam 106 may be fastened to the rest of the structure which was obtained at step 710, to obtain the assembled RUPD 100.
[085] It is intended that the disclosure and examples be considered as exemplary only, with a true scope and spirit of disclosed embodiments being indicated by the following claims.

Claims

We claim:

1. A rear underrun protective device (RUPD) (100) for a vehicle, the RUPD (100) comprising:
a pair of first members (102A, 102B), each of the pair of first members (102A, 102B) configured to be coupled to the vehicle via a top portion of each of the pair of first members (102A, 102B), wherein each of the pair of first members (102A, 102B) is further configured to be coupled to the vehicle in substantially vertical orientation of each of the pair of first members (102A, 102B);
a pair of connecting members (104A, 104B), each of the pair of connecting members (104A, 104B) configured to be coupled to a respective first member of the pair of first members (102A, 102B) via a bottom portion of the respective first member of the pair of first members (102A, 102B) and via a front portion of each of the pair of connecting members (104A, 104B), wherein each of the pair of connecting members (104A, 104B) is further configured to be coupled to a respective first member of the pair of first members (102A, 102B) in a substantially horizontal orientation of each of the pair of connecting members (104A, 104B); and
a crash-beam member (106) configured to be coupled to each of the pair of connecting members (104A, 104B) via a rear portion of each of the pair of connecting members (104A, 104B) in a substantially horizontal configuration of the crash-beam member (106), and substantially perpendicular to each of the pair of connecting members (104A, 104B), wherein:
at least one of: the pair of first members (102A, 102B), the pair of connecting members (104A, 104B), and the crash-beam member (106) comprises a plurality of respective sub-members stacked into each other.

2. The RUPD (100) as claimed in claim 1, wherein:
each of the pair of first members (102A, 102B) comprises a plurality of first sub-members (202), wherein the plurality of first sub-members (202) is configured to be stacked into each other,
each of the pair of connecting members (104A, 104B) comprises a plurality of connecting sub-members (204), wherein the plurality of connecting sub-members (204) is configured to be stacked into each other, and
the crash-beam member (106) comprises a plurality of crash-beam sub-members (206), wherein the plurality of crash-beam sub-members (206) is configured to be stacked into each other.

3. The RUPD (100) as claimed in claim 2, wherein:
each of the plurality of first sub-members (202) has a C-shaped section,
each of the plurality of connecting sub-members (204) has a C-shaped section, and
each of the plurality of crash-beam sub-members (206) has a C-shaped section.

4. The RUPD (100) as claimed in claim 3, wherein the plurality of crash-beam sub-members (206) comprise:
a plurality of crash-beam top sub-members (206(t)), each of the plurality of crash-beam top sub-members (206(t)) having a C-shaped section, and
a plurality of crash-beam bottom sub-members (206(b)), each of the plurality of crash-beam bottom sub-members (206(b)) having a C-shaped section,
wherein the plurality of crash-beam top sub-members (206(t)) is positioned on the plurality of crash-beam bottom sub-members (206(b)) in an inverted position relative to the plurality of crash-beam bottom sub-members (206(b)), to form a substantially rectangular cross section of the crash-beam member (106).

5. The RUPD (100) as claimed in claim 1, wherein each of the pair of connecting members (104A, 104B) is configured to be coupled to a respective first member of the pair of first members (102A, 102B) via one or more shear clips.

6. The RUPD (100) as claimed in claim 1, wherein each of the pair of connecting members (104A, 104B) is further configured to be coupled to a respective first member of the pair of first members (102A, 102B) via one or more vertical gusset plates.

7. The RUPD (100) as claimed in claim 1, wherein the crash-beam member (106) is configured to be coupled to each of the pair of connecting members (104A, 104B) via one or more horizontal gusset plates.

8. The RUPD (100) as claimed in claim 1, wherein:
the material of the pair of first members (102A, 102B), the pair of connecting members (104A, 104B), and the crash-beam member (106) is aluminium-based alloy, and
wherein aluminium-based alloy is aluminium 6061 T6 alloy.

9. The RUPD (100) as claimed in claim 2,
wherein thickness of each of the plurality of first sub-members (202), each of the plurality of connecting sub-members (204), and each of the plurality of crash-beam sub-members (206) is same, and
wherein the thickness of each of the plurality of first sub-members (202), each of the plurality of connecting sub-members (204), and each of the plurality of crash-beam sub-members (206) is 2.5 milli meters.

10. A vehicle (300) comprising:
a chassis (302); and
a rear underrun protective device (RUPD) (100) coupled to the chassis, the RUPD (100) comprising:
a pair of first members (102A, 102B), each of the pair of first members (102A, 102B) configured to be coupled to the chassis (302) via a top portion of each of the pair of first members (102A, 102B), wherein each of the pair of first members (102A, 102B) is further configured to be coupled to the chassis in substantially vertical orientation of each of the pair of first members (102A, 102B);
a pair of connecting members (104A, 104B), each of the pair of connecting members (104A, 104B) configured to be coupled to a respective first member of the pair of first members (102A, 102B) via a bottom portion of the respective first member of the pair of first members (102A, 102B) and via a front portion of each of the pair of connecting members (104A, 104B), wherein each of the pair of connecting members (104A, 104B) is further configured to be coupled to a respective first member of the pair of first members (102A, 102B) in a substantially horizontal orientation of each of the pair of connecting members (104A, 104B); and
a crash-beam member (106) configured to be coupled to each of the pair of connecting members (104A, 104B) via a rear portion of each of the pair of connecting members (104A, 104B) in a substantially horizontal configuration of the crash-beam member (106), and substantially perpendicular to each of the pair of connecting members (104A, 104B), wherein,
at least one of: the pair of first members (102A, 102B), the pair of connecting members (104A, 104B), and the crash-beam member (106) comprises a plurality of respective sub-members stacked into each other.