The present disclosure relates to a blast absorbing structure and system for use in decreasing the extent of catastrophic injury to the occupants of a vehicle, including a military vehicle subjected to a blast. More specifically, the structure and system absorbs the energy from a blast before it reaches the lower extremities of the occupants in the vehicle cabin.
Armored vehicles are frequently threatened by improvised explosive devices (IEDs) designed to cause harm to the vehicle and its occupants. IEDs are typically one or more grouped artillery shells redeployed and detonated in an effort to inflict casualties. These explosive devices when detonated beneath a floor of a vehicle, often create localized deformation of the floor of the vehicle thereby transmitting large vertical loads onto the lower extremities of occupants of the vehicle. For example, detonations below the underbelly of an armored vehicle may cause the vehicle floor to accelerate at 100G or more and reach velocities of 7 to 12 m/s over a time period of 3 to 5 msec. These high rates of acceleration and velocity transmit large mechanical forces on the lower extremities of the occupants within the vehicle cabin, often resulting in catastrophic injury or worse.
Armor countermeasures typically consist of heavy metal plates placed between the threat and the vehicle in such a way as to resist hull breach and aggressive floor accelerations. These heavy metal plates also work in concert with layers of additional metal, ceramic, composite or plastic materials designed to prevent lethal high velocity fragments from entering the vehicle. The heavy metal plates are typically mounted to the underside of the vehicle in shapes to take advantage of venting efficiency, inherent geometric stiffness, and deflection characteristics when presented with incoming pressure and fragmentation. Carrying a heavy blast and fragment resistant hulls results in significant performance disadvantage to the vehicle in terms of reduced fuel economy, lost cargo capacity and increased transportation shipping costs.
In addition to the outer metal plates, the interior of the personnel cabin may include a blast mat. During a blast event on an armored vehicle, the lower extremities of the occupants of the vehicle are frequently subjected to injuries from the blast energy being transmitted through the vehicle structure. One current solution to dissipate the energy is to use blast mats where the occupants of the vehicle rest their feet. However, current blast mats are expensive and heavy, often contributing unwanted additional weight to an already heavy vehicle.
Therefore, there is a need for an efficient, cost-effective energy absorbing structures and systems for use during a high acceleration event, such as a blast event underneath the vehicle. The present structures and system are usable, for example, in a personnel cabin of a vehicle, specifically as an interior structure or floor, and includes an energy absorbing structure for absorbing and dissipating the blast forces from an explosive device, thereby lessening the impact of the forces on the lower extremities of the occupants of the vehicle. One such blast absorbing structure includes a stepped floor design, having a bottom section and side sections incorporating a plurality of steps or ridges. In another embodiment, the blast absorbing structure includes a blast abatement structure assembly having an expandable-style floor plate. Energy absorbing supports may also be used in connection with the blast absorbing structures creating a “floating floor” to improve the absorption and dissipation of forces exerted on the underbelly of the vehicle during a blast event, while avoiding the negative tradeoffs of alternative designs.
There is disclosed herein a structure and assembly, each of which avoids the disadvantages of prior structures and devices while affording additional structural and operating advantages.
Generally speaking, a blast absorbing structure and system for use in absorbing blast forces exerted on a floor of a personnel cabin of a vehicle are disclosed.
In an embodiment, a blast absorbing flexing structure for use in absorbing blast force energy exerted on an underside of a personnel cabin of a vehicle, is disclosed. The blast absorbing flexing structure comprises a bottom section forming a floor of the cabin, a first side section extending from the bottom section, the first side section having a plurality of steps along a length of the first side section, a second side section extending from the bottom section and opposite to the first side section, the second side section having a plurality of steps along a length of the second side section, wherein the bottom and side sections form an absorption component cooperatively movable between an initial position and a blast force position to diminish the blast forces prior to the blast forces to reaching an occupant of the cabin.
In another embodiment, a blast absorbing expanding structure for use in absorbing blast force energy exerted on an underside of a personnel cabin of a vehicle, is disclosed. The blast absorbing expanding structure comprises a blast abatement device forming a floor of the cabin, a cover plate having a plurality of slots arranged around a perimeter of the plate, the cover plate attached to a top surface of the device, and wherein the cover plate is movable between an initial position and a blast force position to diminish the blast forces prior to the blast forces to reaching an occupant of the cabin.
In yet another embodiment, a blast absorbing movable structure for use in absorbing blast force energy exerted on an underside of a personnel cabin of a vehicle, is disclosed. The blast absorbing movable structure comprises a blast abatement device forming a floor of the cabin, a protective panel positioned over the device, and a plurality of energy absorbing slots arranged within the cover, wherein the panel is movable between a neutral position and a blast force position upon application of the blast force on the underside of the cabin and dissipation of blast force energy through the slots.
These and other features and advantages of the present structure and assembly can be more readily understood from the following detailed discussion with reference to the appended drawing figures.
Referring to
One embodiment of the blast energy absorbing structure, specifically a blast absorbing flexing structure 10 is shown in
The bottom 12 and side sections 14, 16 and the supports 20 of the blast energy absorbing structure 10 can be constructed from a variety of material, including, but not limited to steel, aluminum, aluminum honeycomb, and any variety of plastics and composites of the same. Construction of the sections and associated personnel cabin can be accomplished by known methods of construction.
As illustrated in
As shown in
The blast abatement device 102 and cover plate or panel 104 of the blast energy expanding structure 100 may be constructed from a variety of material, including, but not limited to steel, aluminum, aluminum honeycomb, and any variety of plastics and composites of the same. Construction of the components and the associated personnel cabin can be accomplished by known methods of construction.
As shown in
The energy absorbing support 108 may be constructed from any suitable material such as a foamed material, including, but not limited to foamed aluminum, aluminum honeycomb, synthetic foams, such as polystyrene and/or polyethylene, other plastics, etc. Regardless of the material used for the supports, the material must be able to both support the normal walking loads (for example, a 300 pound load spread over a foot pressure representative area results in a deflection characteristic of existing production vehicle floors) and within a common specified working temperature range (−50° F. to 160° F.). Finally, the material must progressively crush during a blast load.
In operation, and as described, the various components of the blast absorbing structures and system 10, 100 work separately and in conjunction to dissipate at least some of the energy exerted on the underbelly of a vehicle cause by, for example, the explosion of an IED below the vehicle. In various exemplary embodiments, when an IED, or similar explosive device, is detonated below the vehicle, the force of the explosion causes the lower floor structure 12 of the vehicle to deform. This deformation in turn forces the floor against the lower extremities of any occupants of the vehicle. The blast absorbing system deforms and slows the upward motion of the force to help dissipate the force being exerted on the lower extremities of the occupants, thereby reducing the likelihood of injury to the occupants.
It should be appreciated that the above-referenced forces may include general deformation forces, localized deformation forces, general displacement forces, localized displacement forces, or any other force that may be exerted upon the underbelly of a vehicle.
It should also be appreciated that, while the above discussion is related to deformation forces caused by, for example, IED explosions, the disclosed embodiments may be usable to dissipate other forces, such as, for example, blunt forces impacts, grenade detonations, small arms fire, and any other force that may be exerted upon the underbelly of a vehicle.
This application claims the benefit of U.S. Provisional Patent Application Ser. No. 61/693,059 filed on Aug. 24, 2012.