ARL applies engineering and physiology expertise to live-fire testing of under-body blast
April 15, 2013
- ARL's approach to UBB live-fire testing leverages the mechanical-engineering experts in the Engineering Analysis Branch and the crew-injury-physiology experts in the Warfighter Survivability Branch (WSB)
- Explaining the benefits of live-fire testing of UBB, Coard said, "Through live-fire tests, we have been able to provide a comprehensive characterization of the blast environment and occupant injuries during a UBB. Only by understanding the mechanism of injury can we apply engineering changes [to vehicles] to decrease the likelihood of those injuries. The blast environment is unique."
- For UBB testing, ARL's analysis has two foci: the structural response of the vehicle and the survivability of its occupants
Buried or surface-laid blast munitions beneath vehicles are a major class of threat that has increased substantially over the last decade. Because of this recent shift, the test and evaluation (T&E) of vehicles and equipment against such under-body blast (UBB) threats is central to ensuring that the survivability of the Solider is being assessed against relevant threats. The major areas of concern are the vehicle's response to the blast and the occupants' injuries.
Analyses by the U.S. Army Research Laboratory's (ARL's) Survivability/Lethality Analysis Directorate (SLAD) have led to improvements in many aspects of vehicle design including energy attenuating systems, suspension, floors, seats, seatbelts, gunner restraints, stowage, component placement, heating and ventilation systems, armor, interior spall curtains and emergency egress systems. ARL's concern is always the same: how can a vehicle be modified to reduce the likelihood and severity of UBB's injuries to vehicle occupants?
ARL's experts leverage an ever-growing wealth of test data. According to Scott Welling, a member of SLAD's Engineering Analysis Branch, "Currently, the T&E community is working to a standard that ten years ago would have been unimaginable. The number of data channels that are used today in a UBB test event is greater than five times the amount used prior to these conflicts."
ARL's approach to UBB live-fire testing leverages the mechanical-engineering experts in the Engineering Analysis Branch and the crew-injury-physiology experts in the Warfighter Survivability Branch (WSB). Welling and Sarah Coard are partners as ARL's representatives on the integrated product team for live-fire testing. Their partnership ensures a comprehensive analysis of the survivability of both the crew and their vehicle.
Explaining the benefits of live-fire testing of UBB, Coard said, "Through live-fire tests, we have been able to provide a comprehensive characterization of the blast environment and occupant injuries during a UBB. Only by understanding the mechanism of injury can we apply engineering changes [to vehicles] to decrease the likelihood of those injuries. The blast environment is unique." And of the value of the live-fire collaboration with the Army Test and Evaluation Command and others, Coard added, "There is no other place where you will get the data we have. [Others] simply do not run as many tests."
Another use for the data may be surprising: improving the test instrumentation itself and refining and enhancing the test scenarios. One such instrument is the anthropomorphic test device (ATD), a crash-test dummy originally developed by the automotive industry. For UBB testing, it has become obvious that the ATD must be modified if it is to provide the most accurate data. So ARL is now leading an experimentation program to enhance the ATD for use in future tests.
Not only is instrumentation improving, but test designs have also become more sophisticated. In the past, a vehicle would often be tested with one ATD in it. Now, it is required that there be an ATD in every occupant location in a vehicle. Another significant change is the adoption of new and current injury criteria in order to make assessments more accurate and to achieve greater resolution in inferring what injuries would result and how. A further way that test design has evolved is by the introduction of new methodologies to analyze the motion of seats and floors.
The current war-time environment has caused testing specifications to grow and timelines to shrink. SLAD, along with the rest of the T&E community, has been responding to urgent materiel releases. Reports that previously would have been needed in thirty days are now requested in twenty-four hours. And where the testing has uncovered opportunities to provide a higher degree of protection and survivability, not only have developmental programs been redesigned, but many vehicles already deployed have even been modified in the field.
Because of ARL's subject-matter expertise, their role is not limited to analyzing the data coming out of a test. Their involvement starts with the test planning, where they recommend best practices for test setup and any necessary experimentation and assist in writing the test plans along with the evaluators, the Army Evaluation Center, and the tester, Aberdeen Test Center. In the next step, ARL assists in prepping the test on paper. They also participate at the test, ensuring that the test plan is followed.
After the shot, ARL analyzes the forensic data captured by the many sensors placed throughout the vehicle. They then provide analytical results to evaluators to use as the basis of their vehicle and occupant evaluations.
For UBB testing, ARL's analysis has two foci: the structural response of the vehicle and the survivability of its occupants. For every vehicle or piece of equipment tested, ARL analyzes the UBB's effects on communications, mobility, firepower and mission success. Because the analysis demands so much more than merely capturing data, a holistic vantage point is vital. ARL's unique expertise and experiences enable them to provide this context to evaluators, program managers and vehicle designers.