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Underbody Blast, Crash and Rollover Interior Impact Injury Prevention Technologies

Description:

Non-traditional interior roof military vehicle impact injury prevention technologies address the challenge to provide warfighter survivability, allowing them to complete their mission, by preventing impact related injuries such as skull fractures and neck injuries, otherwise incurred during underbody blast, crash and rollover events. The solution accounts for the full range of occupants to include the 5th female, 50th male, and 95th male occupant sizes. Additionally it takes into account the occupant may be wearing the ACH helmet and additional gear worn on the body of the occupant. The occupant shall be considered restrained during the blast event. Injury data from theater shows mounted warfighter head, neck and upper spine injuries due to occupant impacts with the vehicle interior during blast, crash and rollover events, frequently occur (Head Injury Analysis for DOT & E Study, JTAPIC RFI 2013-N0114, 10APR2013 and 2012-N0161 Blast Injury Prevalence Rate BIPSR, 10JAN2013). Injuries to the head include traumatic brain injuries (TBI) primarily concussions, skull fractures, face fractures and neck/upper spine fractures. The focus of this topic is to reduce injuries related to skull and neck fractures. Traumatic brain injuries are out of scope of this topic. Although it can be assumed that if impact energy is mitigated to reduced fractures, TBI’s related to occupant impacts is also likely to be reduced. Non-traditional technologies may include, and are not limited to; active protective technologies, optimized interior geometric design and a durable, flame resistant exposed surface allowing protection for multiple impact directions. Interior impact protection shall be developed for military vehicle applications, such as; the HMMWV (High Mobility Multi-purpose Wheeled Vehicle, AMPV (Armored Multiple Purpose Vehicle), Abrams, Bradley Fighting Vehicle, Stryker, 20 T Truck and HTV (Heavy Transport Vehicle). Non-traditional technologies are needed to address military vehicle design trade-offs such as; i) minimizing vehicle packaging space claims and non-intrusive designs, and ii) lighter weight than traditional technologies such as energy absorption materials. PHASE I: Phase I entails a feasibility study, concept development, analysis and modeling and simulation, risk analysis, cost analysis and concept design of a non-traditional, roof-mounted impact injury protection mainly focused upon head and neck injury protection. The concept shall utilize one of the US Army tactical and one ground combat vehicle such as; HMMWV (High Mobility Multi-purpose Wheeled Vehicle, AMPV (Armored Multiple Purpose Vehicle), Abrams, Bradley Fighting Vehicle, Stryker, 20 T Truck and HTV (Heavy Transport Vehicle) as the basis for concept development, which are ITARS Export Controlled. Non-traditional technologies will be designed to provide impact protection at AIS (Anatomical Injury Score) of 2 or less. The technology shall provide impact injury protection from multi-directional impacts, have a durable, flame resistant exposed surface and be non-intrusive ensuring the technology does not hinder or encroach upon the mounted warfighter. The technology shall be capable of providing occupant head-neck protection in less than 15 milliseconds, given an impact velocity of 15 miles per hour (24 kilometers per hour). The energy attenuation criterion for head impact protection, will achieve less than 700 HICd (Head Injury Criterion) using the test evaluation method and equipment per FMVSS 201U. HICd is calculated in accordance with the following formula taken from JSSG-2010-7 Crew Systems Crash Protection Handbook (208): Where A_R=[A_x^2+A_y^2+A_z^2 ]^(1/2) Resultant Acceleration magnitude in g units at the dummy head cg. t1 and t2 are any two points in time during the impact event which are separated by not more than a 15 millisecond time (FMVSS 49 CFR 571 208: Occupant Crash Protection, 2013.10.01). Neck impact injury protection shall be designed according to SAE J885, Feb 2011-02, section related to Direct Impact to the Neck and Neck injury due to head inertia loading. Neck impact injury protection shall provide a maximum peak flexion bending moment about the occipital condyle shall not exceed 190 Nm. The maximum peak extension bending moment about the occipital condyle shall not exceed 57 Nm. The maximum peak axial tension shall not exceed 3300N. The maximum peak axial compression shall not exceed 4000 Newtons. The maximum peak fore and aft shear shall not exceed 3100 Newtons. The neck moments are calculated form the following formula: MOCY =MY – FX(0.01778m), where: MOCY = moment y about occipital condyle MY = measured moment from load cell FX = measured force from load cell Durability criterion is to not degrade in performance when exposed to temperatures of MIL-STD-810 Basic Hot and Basic Cold Storage temperatures, humidity and tracked vehicle vibration schedules. The technology concept shall be developed with the intent to not incur holes from abrasion, tear or puncture after being tested to ASTM D2582, ASTM D751, ASTM D2261, ASTM D3384, ASTM 966 or ASTM D1242 or similar standard, based upon the exposed surface sheet material composition, at 1,000 cycles. The technology concept shall be developed with an exposed surface designed to prevent an overhead dripping and melting injuring the occupant, and shall not generate significant heat index, rapid flashing (ignition greater than 15 seconds) or flame spread, smoke or toxicity when exposed to large fire per ASTM E1354 at 50 kW/m2< 200 flaming and non-flaming, FAR 25.853 and have toxicity approval from the U.S. Public Health and Safety Department and TARDEC. When active technologies are being considered/used for innovative technology development, the technology shall be developed with consideration for ASTM D5428-08 Standard Practice for Evaluating the Performance of Inflatable Restraint Modules, ASTM D5427-09 Standard Practice for Accelerated Aging of Inflatable Restraint Fabrics, ASTM D7559/D7559M-09 Standard Test Method for Determining Pressure Decay of Inflatable Restraint Cushions, ASTM D5807-08 (2013) Standard Practice for Evaluating the Over-pressurization Characteristics of Inflatable Restraint Cushions, ASTM D6476-12 Standard Test Method for Determining Dynamic Air Permeability of Inflatable Restraint Fabrics, ASTM D6799 Standard Terminology Relating to Inflatable Restraints. Analytical tools such as Finite Element Analysis and modeling and simulation, shall be used for concept development including pulse development. The outcome of Phase I shall include the scientific and technical feasibility as well as the commercial merit for the technology(s) solution provided. The concept(s) developed shall be supported by sound engineering principles. Supporting data, initial test data, along with material safety data sheets and material specifications shall also be included if available. The projected development and material cost and timing shall be included in the study. PHASE II: Phase II of this effort shall focus upon the validation and correlation of the analytical concepts and pulses developed from Phase I, along with technology prototype fabrication and validation laboratory testing and evaluation. Military vehicle application(s) and integration concepts will be further refined for one or more military vehicle, such as the the HMMWV (High Mobility Multi-purpose Wheeled Vehicle, AMPV (Armored Multiple Purpose Vehicle), Abrams, Bradley Fighting Vehicle, Stryker, 20 T Truck and HTV (Heavy Transport Vehicle). Vehicle specific prototype component design, modeling and simulation analysis as well as early fabrication for purposes of laboratory verification and vehicle interface evaluation. The energy attenuation performance of the technology solution(s) for head-neck impact injury protection shall be in accordance with the criterion in Phase I, and shall be verified during Phase II. Laboratory testing with prototype concept hardware shall also verify the technology solution(s) capability to withstand military vehicle environment and climates for durability and flame, smoke and toxicity resistance as described in Phase I. The technologies shall be designed to be securely attached to the vehicle roof in areas of the vehicle where occupant head-neck impact is projected to occur based upon modeling and simulation. Vehicle packaging space shall be considered relative to the 5th percentile female through to the 95th percentile male, and analysis conducted to verify the occupant’s space requirements are met in accordance with MIL-STD-1472. This system has the potential to be utilized in any Military and Civilian truck and automotive applications. Technology risks and risk mitigation plans shall be clearly identified; design guidelines and lessons learned shall be documented. Any required modifications and re-testing shall be conducted during Phase II. PHASE III: In the final Phase of the project the contractor shall prove out the effectiveness of the system on the AMPV, Stryker, HTV and/or Bradley Fighting Vehicle for underbody blast, crash and rollover conditions, integration, environment, and durability. The technology solutions designed in Phase I and II to a variety of military vehicles, will be tailored specifically for the military specific vehicles for ease of transition to fielded vehicle solutions. Technology risks and risk mitigation plans shall be clearly identified; design guidelines and lessons learned shall be documented. Any required modifications and re-testing shall be conducted during Phase III. Manufacturability shall be verified during Phase III. This system has the potential to be utilized in any Military and Civilian truck and automotive applications, as well as potential naval applications. Additionally the technology will be applicable to commercial automotive and locomotive industries.
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