Effects of Lumbar Spine Assemblies and Body-Borne Equipment Mass on Anthropomorphic Test Device Responses During Drop Tests

2017 ◽  
Vol 139 (10) ◽  
Author(s):  
Daniel Aggromito ◽  
Mark Jaffrey ◽  
Allen Chhor ◽  
Bernard Chen ◽  
Wenyi Yan
Keyword(s):  
Lumbar Spine ◽  
Federal Aviation Administration ◽  
Relative Displacement ◽  
Drop Tower ◽  
Test Device ◽  
Hybrid Iii ◽  
Drop Tests ◽  
Occupant Injury ◽  
Maximum Relative Displacement ◽  
The Impact

When simulating or conducting land mine blast tests on armored vehicles to assess potential occupant injury, the preference is to use the Hybrid III anthropomorphic test device (ATD). In land blast events, neither the effect of body-borne equipment (BBE) on the ATD response nor the dynamic response index (DRI) is well understood. An experimental study was carried out using a drop tower test rig, with a rigid seat mounted on a carriage table undergoing average accelerations of 161 g and 232 g over 3 ms. A key aspect of the work looked at the various lumbar spine assemblies available for a Hybrid III ATD. These can result in different load cell orientations for the ATD which in turn can affect the load measurement in the vertical and horizontal planes. Thirty-two tests were carried out using two BBE mass conditions and three variations of ATDs. The latter were the Hybrid III with the curved (conventional) spine, the Hybrid III with the pedestrian (straight) spine, and the Federal Aviation Administration (FAA) Hybrid III which also has a straight spine. The results showed that the straight lumbar spine assemblies produced similar ATD responses in drop tower tests using a rigid seat. In contrast, the curved lumbar spine assembly generated a lower pelvis acceleration and a higher lumbar load than the straight lumbar spine assemblies. The maximum relative displacement of the lumbar spine occurred after the peak loading event, suggesting that the DRI is not suitable for assessing injury when the impact duration is short and an ATD is seated on a rigid seat on a drop tower. The peak vertical lumbar loads did not change with increasing BBE mass because the equipment mass effects did not become a factor during the peak loading event.

Blast Mitigation Seat Analysis: Evaluation of Lumbar Compression Data Trends in 5th Percentile Female Anthropomorphic Test Device Performance Compared to 50th Percentile Male Anthropomorphic Test Device in Drop Tower Testing

2016 ◽  
Author(s):  
Kelly Bosch
Keyword(s):  
Lumbar Spine ◽  
Vertical Direction ◽  
Drop Tower ◽  
Blast Mitigation ◽  
Test Device ◽  
Military Population ◽  
Data Set ◽  
System Survivability ◽  
Blast Energy ◽  
Hybrid Iii

Although blast mitigation seats are historically designed to protect the 50th percentile male occupant based on mass, the scope of the occupant centric platform (OCP) Technology Enabled Capability Demonstration (TEC-D) within the U.S. Army Tank Automotive Research Development Engineering Center (TARDEC) Ground System Survivability has been expanded to encompass lighter and heavier occupants which represents the central 90th percentile of the military population. A series of drop tower tests were conducted on twelve models of blast energy-attenuating (EA) seats to determine the effects of vertical accelerative loading on ground vehicle occupants. Two previous technical publications evaluated specific aspects of the results of these drop tower tests on EA seats containing the three sizes of anthropomorphic test devices (ATDs) including the Hybrid III 5th percentile female, the Hybrid III 50th percentile male, and the Hybrid III 95th percentile male. The first publication addressed the overall trends of the forces, moments, and accelerations recorded by the ATDs when compared to Injury Assessment Reference Values (IARVs), as well as validating the methodology used in the drop tower evaluations1. Review of ATD data determined that the lumbar spine compression in the vertical direction could be used as the “go/no-go” indicator of seat performance. The second publication assessed the quantitative effects of Personal Protective Equipment (PPE) on the small occupant, as the addition of a helmet and Improved Outer Tactical Vest (IOTV) with additional gear increased the weight of the 5th percentile female ATD more than 50%2. Comparison of the loading data with and without PPE determined that the additional weight of PPE increased the overall risk of compressive injury to the lumbar and upper neck of the small occupant during an underbody blast event. Using the same data set, this technical paper aimed to evaluate overall accelerative loading trends of the 5th percentile female ATD when compared to those of the 50th percentile male ATD in the same seat and PPE configuration. This data trend comparison was conducted to gain an understanding of how seat loading may differ with a smaller occupant. The focus of the data analysis centered around the lumbar spine compression, as this channel was the most likely to exceed the IARV limit for the 5th percentile female ATD. Based on the previous analysis of this data set, the lightest occupant trends showed difficulty in protecting against lumbar compression injuries with respect to the 5th percentile female’s IARV, whereas the larger occupants experienced fewer issues in complying with their respective IARVs for lumbar compression. A review of pelvis acceleration was also conducted for additional kinetic insight into the motion of the ATDs as the seat strokes. This analysis included a review of how the weight and size of the occupant may affect the transmission of forces through a stroking seat during the vertical accelerative loading impulse.

Repeatable Dynamic Rollover Roof Test Fixture

2003 ◽  
Author(s):  
Donald Friedman ◽  
Acen Jordan ◽  
Carl Nash ◽  
Jack Bish ◽  
Terence Honikman ◽  
...  
Keyword(s):  
Longitudinal Axis ◽  
Rolling Motion ◽  
Passenger Compartment ◽  
Test Device ◽  
Test Fixture ◽  
Complete Vehicle ◽  
Entire Vehicle ◽  
Roll Rate ◽  
Drop Tests ◽  
The Impact

Experimental rollover tests have been criticized for their poor emulation of actual rollovers and for their lack of repeatability. We have designed and built a test fixture that overcomes both of these criticisms. The fixture holds a passenger compartment, weighted to match the inertia characteristics of a complete vehicle, or a complete vehicle at the appropriate pitch and yaw. The compartment is then rotated about its principal (longitudinal) axis through an arc that mimics the rolling motion of an entire vehicle. At the appropriate roll angle and falling velocity, the roof strikes a moving patch of concrete. The compartment is controlled throughout the sequence and is suspended after the impact, so that a sequence of impacts can be individually studied in separate tests. Initial tests have shown that we can achieve repeatable impacts. Test variables include pitch, yaw, roll rate and vehicle center of gravity motion (both lateral and vertical velocity). This test device addresses the various shortcomings of previous rollover tests, fixtures and the various static and drop tests of vehicles conducted to determine rollover performance.

scholarly journals The Influence of the Explosive Ordnance Disposal Suit on the Bomb Squad Safety

2018 ◽  
Vol 9 (2) ◽  
pp. 27-44
Author(s):  
Michał GMITRZUK ◽  
Lech STARCZEWSKI ◽  
Krzysztof SZCZEŚNIAK ◽  
Dariusz DANIELEWICZ ◽  
Robert NYC ◽  
...  
Keyword(s):  
Shock Wave ◽  
Chest Wall ◽  
Human Body ◽  
Critical Parameter ◽  
Test Device ◽  
Wall Velocity ◽  
Hybrid Iii ◽  
Plastic Explosive ◽  
Explosive Ordnance Disposal ◽  
The Impact

The article presents a study on the influence of shock wave on a Hybrid III anthropomorphic test device (ATD HIII) equipped with an explosive ordnance disposal (EOD) suit. The shock wave was generated by the detonation of SEMTEX 1A plastic explosive, formed in the shape of a 250 g, 500 g, and 840 g sphere, at a distance of 0.5 m, 1 m, and 2 m. The use of ATD allowed for determining parameters of damage to the human body as a result of the impact of overpressure wave. The experiments also included a measurement of such parameters as forces and moments on lower extremi-ties, acceleration of head and pelvis, and forces and moments on a neck simulator. Chest Wall Velocity Predictor (CWVP), calculated from the pressure measured on ADT’s chest, was adopted as the most critical parameter. It was revealed that the allowed distance of explosion of a 500 g pure explosive, which does not cause exceeding the allowed parameters, is 1 m.

Preliminary FAA-Hybrid III Spinal Injury Criteria for Oblique-Facing Aircraft Seats

2015 ◽  
Author(s):  
John Humm ◽  
David Moorcroft ◽  
Narayan Yoganandan ◽  
Rick DeWeese ◽  
Amanda Taylor ◽  
...  
Keyword(s):  
Lumbar Spine ◽  
Spinal Injury ◽  
Dynamic Condition ◽  
Federal Aviation Administration ◽  
Acceleration Pulse ◽  
Injury Criteria ◽  
Oblique Loading ◽  
Thoracic And Lumbar Spine ◽  
Hybrid Iii ◽  
The One

Occupant injury potential to oblique loading at aircraft crash severities is unknown. The objective of the present study was to derive preliminary injury criteria for the Federal Aviation Administration (FAA) Hybrid III anthropomorphic test device (ATD) under oblique loading conditions. Twelve sled tests were conducted at four pulse severities and three configurations. An acceleration pulse representative of the one specified in Title 14 Code of Federal Regulations Part 25.562, emergency landing dynamic condition for horizontal impact was used as an input. Pulses were scaled in magnitude at 50, 61, 75 and 100% of the peak acceleration 13.7, 10.2, 8.6 and 6.8 m/s, respectively. The three conditions were: 45-degrees, no arm rest, pelvis restrained with two belts, legs restrained; 45-degrees, with arm rest, single lap belt, legs restrained; 30-degrees, no arm rest, two lap belts, legs unrestrained. The ATD was placed on a generic seat representative of aircraft seat geometry and the seat was oriented obliquely. ATD accelerations, thoracic and lumbar spine forces, and restraint forces were recorded. Peak tension forces in the thoracic and lumbar spine ranged from 10–12.7 kN at the highest pulse to 3.6–4.2 kN at the lowest pulse. Previously reported in-house post mortem human surrogate (PMHS) tests provided a matched-paired dataset for combining injuries with ATD metrics. From this limited sample set, 5.2 kN tension force in the spine is suggested for the FAA-Hybrid III ATD as a preliminary injury criteria in oblique loading in the aviation environment.

Analysis of Stand-Up Forklift Operator Injuries in Off-the-Dock and Tip-Over Incidents With a Latched Door on the Operator Access Opening

2016 ◽  
Vol 2 (2) ◽  
Author(s):  
John F. Wiechel ◽  
William R. “Mike” Scott
Keyword(s):  
Head Injury ◽  
High Risk ◽  
High Speed ◽  
Neck Injury ◽  
Thoracic Injury ◽  
Shoulder Injury ◽  
Test Device ◽  
Impact Tests ◽  
Hybrid Iii ◽  
The Impact

A series of tip-over and off-the-dock impact tests were performed with stand-up forklifts to investigate the potential for injury to the operator of a forklift in these types of accidents, when the forklift is equipped with an operator’s compartment door. One Crown Equipment Company 35RRTT Model and one 35RCTT Model stand-up forklifts were used in the impact tests. The only modification to the forklifts for the tests was the placement of a door on the entrance to the operator’s compartment. A Hybrid III anthropomorphic test device (ATD) was placed in the operator’s compartment as a human surrogate. During each test, head accelerations, chest accelerations, neck loads, and lumbar loads were measured on the ATD. The motion of the forklift and the ATD were filmed with real-time video and high-speed cameras. Results from the impact tests indicate that there is a high risk of head injury in a right-side tip-over accident and a high risk of head injury and neck injury in a left-side tip-over accident. There is a high risk of a head injury, neck injury, and thoracic injury in off-the-dock forks-trailing accidents. In an off-the-dock forks-leading accident, there is a high risk of arm/shoulder injury, head injury, and neck injury. In both tip-over and off-the-dock forks-trailing accidents, there is a high probability of an entrapment injury under the overhead guard on the forklift.

The Effect of an Operator Compartment Door on Standup Forklift Off-Dock and Tip-Over Injuries

2013 ◽  
Author(s):  
John F. Wiechel ◽  
William R. (Mike) Scott
Keyword(s):  
Head Injury ◽  
High Risk ◽  
High Speed ◽  
Neck Injury ◽  
Thoracic Injury ◽  
Shoulder Injury ◽  
Test Device ◽  
Impact Tests ◽  
Hybrid Iii ◽  
The Impact

A series of tip-over and off-the-dock impact tests were performed with stand-up forklifts in order to investigate the potential for injury to the operator of a forklift in these types of accidents when the forklift is equipped with an operator’s compartment door. One Crown Equipment Company RR Model and one RC Model stand-up forklift were used in the impact tests. The only modification to the forklifts for the tests was the placement of a door on the entrance to the operator’s compartment. A Hybrid III anthropomorphic test device (ATD) was placed in the operator’s compartment as a human surrogate. During each test, head accelerations, chest accelerations, neck loads and lumbar loads were measured on the ATD. The motion of the forklift and the ATD were filmed with video and high-speed cameras. Results from the impact tests indicate that there is a high risk of head injury in a right side tip-over accident and a high risk of head injury and neck injury in a left side tip-over accident. There is a high risk of a head injury, neck injury and thoracic injury in off-the-dock forks-trailing accidents. In an off-the-dock forks-leading accident there is a high risk of arm/shoulder injury, head injury, and neck injury. In both tip-over and off-the-dock forks-trailing accidents there is a high probability of an entrapment injury under the overhead guard on the forklift.

Identification of the Best Possible Configuration of the Shoulder Strap of a Three-Point Restraint for Motor Coach Occupant Rollover Protection

2011 ◽  
Author(s):  
Chandrashekhar K. Thorbole ◽  
David A. Renfroe ◽  
Hamid M. Lankarani
Keyword(s):  
Seat Belt ◽  
Essential Element ◽  
The United States ◽  
Computational Technique ◽  
Hybrid Iii ◽  
Roll Rate ◽  
Occupant Injury ◽  
Occupant Injuries ◽  
Serious Injuries ◽  
The Impact

The motor coach is an essential element of the mass transportation system in the United States and all around the globe. Rollover accidents associated with any motor coach without an adequate occupant protection system may result in serious or fatal occupant injuries. The seat belt is an essential safety device in protecting an occupant in a rollover accident. It has been observed that just a quarter roll of a bus results in fatal injuries to an unbelted occupant. This severe nature of occupant injury in a less severe bus roll is attributable to the large flying distance within the unpadded interior and the impact with other fellow occupants. In this situation the presence of a seat belt is mandatory to protect the occupants from serious injuries by preventing their ejection from their seats. The three-point restraint is the best possible solution for the motor coach seat belt requirement. The understanding of shoulder strap placement with respect to the occupant is important information. This information facilitates the best possible seat belt configuration for all occupants which will minimize the slippage of the shoulder strap during a rollover accident. The slipping of the shoulder strap is a function of rollover type, rollover direction, roll rate and the occupant location in a vehicle with respect to roll direction. A Finite Element bus model is used to conduct a trip rollover simulation at two different trip velocities. The motion file, as obtained from this simulation, is used to prescribe motion to a MADYMO facet bus model. The standard Hybrid III 50th percentile ATD (Anthropomorphic Test Device) is used to model all the belted occupants. The FE belt model is used to facilitate the simulation of slippage on the shoulder. This study demonstrates the best possible configuration of the three-point restraints for motor coach occupants in a rollover accident using the computational technique. Knowledge of this kind will help the industry to identify and implement seat belts with the best configuration for occupant rollover protection.

ON TESTING THE SHOCK-ABSORBING SEATS FOR HELICOPTER CREW MEMBERS

2021 ◽  
Vol 55 (3) ◽  
pp. 62-65
Author(s):  
Yu.B. Moiseev ◽  
Keyword(s):  
Dynamic Performance ◽  
Impact Testing ◽  
The Other ◽  
Test Device ◽  
Anthropometric Data ◽  
Test Platform ◽  
Helicopter Pilots ◽  
Hybrid Iii ◽  
Male Hybrid ◽  
The Impact

Recommendations on improving the dynamic performance of shock-absorbing seats for helicopter pilots resulted from analysis of the Russian pilots' anthropometric data and helicopter 3-d attitude and position during emergency landing. The idea is to complement the existing list of impact tests with two more tests in which the impact vector will be perpendicular to the test-platform horizontal. One of these tests should be performed with a light anthropomorphic test device (Hybrid-III) representing a 5-percentile female and the other, heavy Hybrid-III representing a 95-percentile male. For horizontal impact testing, the 50-percentile male Hybrid-III should be replaced by the 95-percentile Hybrid-III.

An Investigation of Hybrid III and Living Human Drop Tests

2000 ◽  
Vol 28 (1-2) ◽  
pp. 219-223 ◽  
Author(s):  
Keith Friedman ◽  
Fiona Gaston ◽  
Jack Bish ◽  
Donald Friedman ◽  
Anthony Sances, Jr.
Keyword(s):  
Hybrid Iii ◽  
Drop Tests

Time and temperature sensitivity of the hybrid III lumbar spine

2021 ◽  
pp. 1-6
Author(s):  
Allison L. Schmidt ◽  
Maria A. Ortiz-Paparoni ◽  
Jay K. Shridharani ◽  
Roger W. Nightingale ◽  
Frank A. Pintar ◽  
...  
Keyword(s):  
Lumbar Spine ◽  
Temperature Sensitivity ◽  
Hybrid Iii
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