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 100 G 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 on the floor 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 system for use during a high acceleration event, such as a blast event underneath the vehicle. The present structure and system is usable, for example, in a personnel cabin of a vehicle, specifically as a floor, and includes an energy absorbing device 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. The device includes energy absorbing supports, a flat panel or surface positioned on top of the supports, and at least one retainer or guide to maintain the movement direction of the surface. The energy absorbing supports suspended the top surface, 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 system, each of which avoids the disadvantages of prior structures and devices while affording additional structural and operating advantages.
Generally speaking, a blast absorbing structure for use in absorbing blast forces exerted on a floor of a personnel cabin of a vehicle is disclosed.
In an embodiment, the blast structure comprises a first absorption component for initial absorption of the blast forces exerted on the floor of the vehicle and a second absorption component for secondary absorption of the blast forces, wherein the first and second absorption components cooperatively move 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 system for use on a floor of a personnel cabin of a vehicle, is disclosed. The system comprises at least one energy absorbing component, a floating surface supported by the energy absorbing component, the floating surface moveable between an initial position and a blast force position, and a guide for retaining the floating surface in a horizontal position, wherein upon receipt of a blast force upon the floor, the energy absorbing components deform to absorb the blast force and diminish movement of the floating surface from the initial position to the blast force position.
These and other features and advantages of the present structure and system can be more readily understood from the following detailed discussion with reference to the appended drawing figures.
Referring to
As shown in
The energy absorbing support 20 can 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.
As shown in
The surface 30 or second absorption component 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 surface can be accomplished by any suitable method including cutting, metal molding, plastic injection molding, forming, bonding welding, etc.
As illustrated in
In addition to the energy absorbing supports 20 and the moving floor 30, the structure 10 also includes a guide or retainer. Specifically, and as shown in
In operation, and as described, the various components of the blast absorbing structure and system 10 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, embodiments described herein 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. 61/615,694 filed on Mar. 26, 2012.
Number | Date | Country | |
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61615694 | Mar 2012 | US |