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Abstract: The objectives of this study were to provide insights on how injury risk is influenced by occupant demographics such as sex, age, and size; and to quantify differences within the context of commonly-occurring real-world crashes. The analyses were confined to either single-event collisions or collisions that were judged to be well-defined based on the absence of any significant secondary impacts. These analyses, including both logistic regression and descriptive statistics, were conducted using the Crash Investigation Sampling System for calendar years 2017 to 2021. In the case of occupant sex, the findings agree with those of many recent investigations that have attempted to quantify the circumstances in which females show elevated rates of injury relative to their male counterparts given the same level bodily insult. This study, like others, provides evidence of certain female-specific injuries. The most problematic of these are AIS 2+ and AIS 3+ upper-extremity and lower-extremity injuries. These are among the most frequently observed injuries for females, and their incidence is consistently greater than for males. Overall, the odds of females sustaining MAIS 3+ (or fatality) are 4.5% higher than the odds for males, while the odds of females sustaining MAIS 2+ (or fatality) are 33.9% higher than those for males. The analyses highlight the need to carefully control for both the vehicle occupied, and the other involved vehicle, when calculating risk ratios by occupant sex. Female driver preferences in terms of vehicle class/size differ significantly from those of males, with females favoring smaller, lighter vehicles.

Evaluation of DAMAGE Algorithm in Frontal Crashes; Priya Prasad, Saeed D. Barbat, Anil Kalra and Dainius Dalmotas; Stapp Car Crash Journal; Vol. 67; 2024

Abstract: With the current trend of including the evaluation of the risk of brain injuries in vehicle crashes due to rotational kinematics of the head, two injury criteria have been introduced since 2013 - BrIC and DAMAGE. BrIC was developed by NHTSA in 2013 and was suggested for inclusion in the US NCAP for frontal and side crashes. DAMAGE has been developed by UVa under the sponsorship of JAMA and JARI and has been accepted tentatively by the EuroNCAP. Although BrIC in US crash testing is known and reported, DAMAGE in tests of the US fleet is relatively unknown. The current paper will report on DAMAGE in NCAP-like tests and potential future frontal crash tests involving substantial rotation about the three axes of occupant heads. Distribution of DAMAGE of three-point belted occupants without airbags will also be discussed. Prediction of brain injury risks from the tests have been compared to the risks in the real world. Although DAMAGE correlates well with MPS in the human brain model across several test scenarios, the predicted risk of AIS2+ brain injuries are too high compared to real-world experience. The prediction of AIS4+ brain injury risk in lower velocity crashes is good, but too high in NCAP-like and high speed angular frontal crashes.

An NCAP Rating for Females; Digges K, Dalmotas D and Prasad P; Paper No. 23-0323; Proc. 27th ESV Conf; Yokohama, Japan; April 3-6, 2023
Download the full-text article as a PDF file (1.6 MB)

Abstract: This paper defines NCAP rating factors that would be useful to improve the safety of females in frontal crashes. The study is based on an analysis crash tests available on the NHTSA website and analysis of Crash Investigation Sampling System (CISS) and Crash Report Sampling System (CRSS) data.

Analysis of NHTSA databases of crash tests and collision data suggest that a Female NCAP should focus on encouraging crash safety countermeasures in three priority areas - reducing chest injuries, reducing lower limb injuries (especially foot and ankle injuries) and reducing the crash severity in lower speed crashes.

Based on the available literature and the additional data analysis, proposals are offered for a Female NCAP to address the three principal issues. These include better controls of the safety belt and foot positioning, measuring chest and foot/ankle injury risk more accurately, limiting brake pedal motion and limiting the initial frontal stiffness of vehicles.

Application of Multiple Rib Gages to Improve Chest Injury Measurements; Digges K, Dalmotas D and Prasad P; Paper No. 19-0266; Proc. 26th ESV Conf.; Eindhoven, Netherlands; June 10-13, 2019
Download the full-text article as a PDF file (1.2 MB)

Abstract: In 2011 the National Highway Traffic Safety Administration (NHTSA) made changes to the new car assessment program (NCAP) frontal full-width test rating that introduced a chest deflection metric. The dummy seating protocol did not specify routing procedures that consistently control shoulder belt positioning on the dummy. Thus, most NCAP tests were conducted with the D-ring in the full up position, placing the shoulder belt far above the center chest potentiometer, thereby loading the dummy's chest asymmetrically.

Previous research showed that differences in chest deflection measurement caused by variations in belt routing are not trivial, and correspond to a risk of serious chest injury, especially for older females. The objective of the present study is to investigate the use of supplementary chest deformation sensors, such as RibEye and IR-TRACCs for identifying belt fitment procedures which provide accurate chest readings by ensuring that the shoulder belt is routed near the dummy's center chest gage.

The results indicate greater disparity between the center chest gage measurements and the supplemental RibEye or IR-TRACC readings when the belt routes higher on the dummy's neck, associated with the upper anchorage D-ring in the full up position. For both the 50th male and 5th female right front passenger dummies, when the belt was routed closer to the dummy's design intention at the center gage, the center gage and left side supplemental (RibEye or IR-TRACC) measurements were similar. Additionally, when the belt was placed across the center of the dummy's chest, the supplemental sensors deflected quite uniformly across the chest.

RibEye and IR-TRACC supplemental chest deflection technologies have the potential to better identify belt routings consistent with the design characteristics of the dummy chest and deflection sensor. This knowledge could be used to develop testing and belt placement protocols, support more meaningful and consistent estimates of chest injury risk, and greatly enhance the utility of NCAP programs to drive restraint system changes to further reduce real-world chest injuries.

The Need to Better Control Belt Routing for Silver NCAP Ratings; Digges K, Dalmotas D, Prasad P and Mueller B; Paper No. 17-0403-O; Proc. 25th ESV Conf.; Detroit, MI; June 8-11, 2017
Download the full-text article as a PDF file (1.1 MB)

Abstract: In 2011 NHTSA made changes to the NCAP frontal full-width test rating that introduced a chest deflection metric. The dummy seating protocol did not specify routing procedures that consistently control shoulder belt positioning on the dummy. Thus, most NCAP tests were conducted with the D- ring in the fully up position, placing the shoulder belt far above the center chest potentiometer.

Sled and full-vehicle crash tests of a 2011 Dodge Caliber demonstrated that for the 5 th percentile small female passenger dummy, the high D-ring position causes the belt to cross the chest above the location of the deflection potentiometer. The ribeye gauges show that this belt configuration produces deflection measurements that are higher than those measured by the center potentiometer.

The differences in chest deflection measurement caused by variations in belt routing are not trivial. For the Caliber, the NHTSA NCAP test produced a chest deflection of 11.8 mm, corresponding to a risk of serious chest injury for older females of 0.6%. A crash test conducted by IIHS under the same conditions but with the belt routed across the deflection potentiometer produced a chest deflection of 34.5 mm, corresponding to a risk of serious chest injury for older females of 44.7%.

Mertz HJ, Prasad P, Dalmotas DJ and Irwin AL; Age-specific injury risk curves for distributed, anterior thoracic loading of various sizes of adults based on sternal deflections; Paper No. 2016-22-0001; Stapp Car Crash Journal; pp. 1-9; Vol. 60; 2016
Full-text paper available from SAE

Abstract: Injury Risk Curves are developed from cadaver data for sternal deflections produced by anterior, distributed chest loads for a 25, 45, 55, 65 and 75 year-old Small Female, Mid-Size Male and Large Male based on the variations of bone strengths with age. These curves show that the risk of AIS = 3 thoracic injury increases with the age of the person. This observation is consistent with NASS data of frontal accidents which shows that older unbelted drivers have a higher risk of AIS = 3 chest injury than younger drivers.

Prasad P, Dalmotas D and Chouinard A; Side Impact Regulatory Trends, Crash Environment and Injury Risk in the USA; Paper No. 2015-22-0004; Stapp Car Crash Journal; Volume 59; November, 2015
Full-text paper available from SAE

Abstract: Light duty vehicles in the US are designed to meet and exceed regulatory standards, self-imposed industry agreements and safety rating tests conducted by NHTSA and IIHS. The evolution of side impact regulation in the US from 1973 to 2015 is discussed in the paper along with two key industry agreements in 2003 affecting design of restraint systems and structures for side impact protection. A combination of all the above influences shows that vehicles in the US are being designed to more demanding and comprehensive requirements than in any other region of the world.

The crash environment in the US related to side impacts was defined based on data in the nationally representative crash database NASS. Crash environment factors, including the distribution of cars, light trucks and vans (LTV's), and medium-to-heavy vehicles (MHV's) in the fleet, and the frequency of their interactions with one another in side impacts, were considered. Other factors like, crash severity in terms of closing velocity between two vehicles involved in crash, gender and age of involved drivers in two-vehicle and single vehicle crashes, were also examined.

Injury risks in side impacts to drivers and passengers were determined in various circumstances such as near-side, far-side, and single vehicle crashes as a function of crash severity, in terms of estimated closing speed or lateral delta-V. Also injury risks in different pairs of striking and struck cars and LTV's, were estimated. A logistic regression model for studying injury risks in two vehicle crashes was developed. The risk factors included in the model include case and striking vehicles, consisting of cars, SUV's, vans, and pickup trucks, delta-V, damage extent, occupant proximity to the impact side, age and gender of the occupant, and belt use. Results show that car occupants make up the vast majority of serious-to-fatally injured occupants. Injury rates of car occupants in two-vehicle collision are highest when the car is struck by a pickup and lowest when struck by a car. This was the case across all lateral delta-V ranges. Additionally, near-side injury rates are substantially higher than those in far-side impacts.

Prasad P, Dalmotas DJ and German A; The Incidence and Severity of Small Overlap Frontal Crashes in NASS-CDS; Paper No. 15-0182-O; Proc. 24th ESV Conf.; Gothenburg, Sweden; June 8-11, 2015
Download the full-text article as a PDF file (1.82 MB)

Abstract The Insurance Institute for Highway Safety has recently introduced a small overlap frontal crash test in its frontal rating scheme. Another small overlap frontal crash test is under development by the National Highway Traffic Safety Administration (NHTSA). Whereas the IIHS test is conducted against a fixed rigid barrier, the NHTSA test is conducted with a moving deformable barrier that overlaps 35% of the vehicle being tested and the angle between the longitudinal axis of the barrier and the longitudinal axis of the test vehicle is 15 degrees. The field relevance of the IIHS test and the NHTSA test has been the subject of previous papers by Prasad et al. The current study is aimed at examining the combined relevance of the two tests as representing frontal corner impacts involving small overlap. The field relevance is indicated by the frequency of occurrence of real world crashes that are simulated by the test conditions, the proportion of serious-to-fatal real world injuries explained by the test conditions, and rates of serious injury to the head, chest and other body regions in the real world crashes resembling the test condition. The database examined for real world crashes is NASS-CDS. The frontal corner impacts as represented by the 25% Small overlap frontal and the NHTSA tests together address slightly less than 9% of all frontal crashes and 6% to 12% of all MAIS3+F injuries to the drivers in these crashes. The IIHS test has a somewhat higher contribution in both the incidence and severity. The two crash modes together address 4.6% to 8.2% of all MAIS3+F head injuries. Similarly, the proportion of all frontal MAIS3+F chest injuries addressed by the two crash modes or corner tests is estimated to be 6% to 10.6%. The available data for the passenger involved in driver-side frontal corner crashes indicate that elderly female occupants predominantly experience serious head and chest injuries. All, except one, injured passengers were females. The average age of injured females who had chest injuries was slightly over 65 years. Injury rates of the head and the chest are substantially lowered in far-side than in near-side frontal impacts. Crash test ATD rotational responses of the head in the tests substantially over predict the real world risk of serious-to-fatal brain injuries.

German A, Dalmotas DJ, Prasad P and Comeau J-L; Ejections and Fatalities in Single-Vehicle Rollover Crashes: A Question of Restraint; Proceedings of the 25th CARSP Conference; Ottawa, ON; May 27-30, 2015
Download the full-text article as a PDF file (675 KB)

Abstract In recent years, due to initiatives such as Road Safety Vision 2010, and the National Occupant Restraint Program, Canada has seen reductions in casualties resulting from motor vehicle collisions. Indeed, the most recent collision statistics, published in 2012, show the lowest death toll on the nation's roads in almost sixty years. Furthermore, the most recent seat belt surveys, conducted in 2009-10, indicate that Canadians are buckling up in motor vehicles more than ever, with an overall usage rate in excess of 95%. Despite these very encouraging signs, the percentage of motor vehicle occupants who are fatally injured while not using seat belts remains unacceptably high at more than 35%. This problem is particularly well exemplified by fatalities resulting from single-vehicle rollover crashes. Such collisions frequently occur as a result of loss of directional control on the part of the driver, and involve vehicle yaw and a lateral rollover, a crash mode that is often benign. Belted occupants are generally retained inside the vehicle and come to little harm. However, such may well not be the case for the unbelted who are in considerable danger of being ejected from the vehicle, with the consequent potential for serious or fatal injury. The present study looks at this latter issue, both from the perspective of the national collision picture, and from a series of in-depth investigations of fatal crashes.

Prasad P, Dalmotas DJ and German A; The Field Relevance of NHTSA's Oblique Research Moving Deformable Barrier Tests; Paper No. 2014-07; Stapp Car Crash Journal; Volume 58; pp. 175-196; November, 2014
Full-text paper available from SAE

Abstract: A small overlap frontal crash test has been recently introduced by the Insurance Institute for Highway Safety in its frontal rating scheme. Another small overlap frontal crash test is under development by the National Highway Traffic Safety Administration (NHTSA). Whereas the IIHS test is conducted against a fixed rigid barrier, the NHTSA test is conducted with a moving deformable barrier that overlaps 35% of the vehicle being tested and the angle between the longitudinal axis of the barrier and the longitudinal axis of the test vehicle is 15 degrees. The field relevance of the IIHS test has been the subject of a paper by Prasad et al. (2014). The current study is aimed at examining the field relevance of the NHTSA test. The field relevance is indicated by the frequency of occurrence of real world crashes that are simulated by the test conditions, the proportion of serious-to-fatal real world injuries explained by the test condition, and rates of serious injury to the head, chest and other body regions in the real world crashes resembling the test condition. The database examined for real world crashes is NASS. Results of the study indicate that 1.4% of all frontal 11-to-1 o'clock crashes are simulated by the test conditions that account for 2.4% to 4.5% of all frontal serious-to-fatal (MAIS3+F) injuries. Injury rates of the head and the chest are substantially lower in far-side than in near-side frontal impacts. Crash test ATD rotational responses of the head in the tests over-predict the real world risk of serious-to-fatal brain injuries.

Frontal Corner Impacts - Crash Tests and Real-World Experience; D J Dalmotas, A German and P Prasad; Presented at the 6th. International ESAR Conference; Hannover, Germany; June 20-21, 2014
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Abstract: In North America, frontal crash tests in both the regulatory environment and consumer-based safety rating schemes have historically been based on full-width and moderate-overlap (40%) vehicle to barrier impacts. The combination of improved seat-belt technologies, notably belt tensioning and load limiting systems, together with advanced airbags, has proven very effective in providing occupant protection in these crash modes. Recently, however, concern has been raised over the contribution of narrower frontal impacts, involving primarily the vehicle corners, to the incidence of fatality and serious injury as a result of the potential for increased occupant compartment intrusion and performance limitations of current restraint systems. Drawing on data documented in the National Automotive Sampling System (NASS)/ Crashworthiness Data System (CDS) for calendar years 1999 to 2012, the present study examines the characteristics of existing and proposed corner crash test configurations, and the nature of real-world collisions that approximate the test environments. In this analysis, particular emphasis is placed on crash pulse information extracted from vehicle-based event data recorders (EDR's).

Prasad P, Dalmotas D and German A; An Examination of Crash and NASS Data to Evaluate the Field Relevance of IIHS Small Offset Tests; SAE Int. J. Trans. Safety; Vol. 2 No. 2; 2014
Full-text paper available on-line from SAE

Abstract: This paper presents the analysis of a series of frontal crash tests conducted by the Insurance Institute of Highway Safety that are commonly referred to as Small Overlap Impacts (SOI). The occurrence and severity of such frontal impacts in the real world were estimated using two different methods. Both methods used the National Automotive Sampling Scheme (NASS), which is a stratified sample of crashes in the US. The first method utilized an algorithm commonly known as Frontal Impact Taxonomy (FIT). The second method was based on comparison of deformation patterns of vehicles involved in frontal crashes in the NASS data files with those produced in tests conducted by the IIHS. FIT analysis of the data indicate that approximately 7.5% of all 11-1 o'clock frontal crashes in NASS are represented by the IIHS SOI test condition and they account for 6.1% of all serious-to-fatal injuries to front seat occupants restrained by seat belts and airbags. Based on the analysis of test and crash front end damage data, it is estimated that the IIHS SOI test mode represents 3% to 8% of all fatal crashes and 4.6 to 9% of all MAIS3+F injury producing frontal crashes.

Harold J. Mertz, Priya Prasad and Dainius J. Dalmotas; Minimizing the Injury Potential of Deploying Airbag Interactions with Car Occupants; John Paul Stapp Memorial Lecture, 57th Stapp Car Crash Conference; Stapp Car Crash Journal; Vol. 57; SAE International; November, 2013
Full-text paper available on-line from SAE

Abstract: Minimizing the injury potential of the interactions between deploying airbags and car occupants is the major issue with the design of airbag systems. This concern was identified in 1964 by Carl Clark when he presented the results of human volunteer and dummy testing of the "Airstop" system that was being developed for aircraft. The following is a chronological summary of the actions taken by the car manufacturers, airbag suppliers, SAE and ISO task groups, Research Institutes and Universities, and consumer and government groups to address this issue.

Kennerly Digges, Dainius Dalmotas and Priya Prasad; An NCAP Star Rating System for Older Occupants; Paper No. 13-0064; Proc. 23rd ESV Conf.; Seoul, Korea; May 27-30, 2013
Download the full-text paper as a PDF file (421 KB)

Abstract: The objective of the paper was to apply to the NCAP star rating system injury risk functions that are more representative of the injury tolerance of older occupants. The NASS 1998-2008 data for front outboard occupants in NCAP like frontal crashes protected by air bags and safety belts was analyzed to determine injury risks by body region and occupant age groupings. The injury rates for NCAP like crashes were calculated for each applicable body region. Alternative injury risk functions were applied to 302 NCAP tests of vehicles model year 1988-2006. NCAP injury rates were calculated and compared with NASS data. The comparison was used to select injury risk functions to be applied to 2011 NCAP tests. Selected risk functions from the literature that produced injury rates in NCAP tests like those in NCAP like crashes were substituted for NCAP 2011 chest and neck injury risk functions. When applied to the 2011 NCAP tests there was a general downward shift in the star ratings awarded to the driver. However, the number of passengers with 5 star ratings more than doubled. For both drivers and passengers there were vehicles that advanced from 4 stars to 5 stars. The application of this alternative rating system would produce added incentives for safety designs that more correctly prioritize the reduction of injuries most harmful to older occupants.

Priya Prasad, Harold J. Mertz, Dainius J. Dalmotas, Jeffrey S. Augenstein and Kennerly Digges; Evaluation of the Field Relevance of Several Injury Risk Functions; Paper No. 10S-44; Stapp Car Crash Journal; Vol. 54; November, 2010
Full-text paper available on-line from SAE

Abstract: An evaluation of the four injury risk curves proposed in the NHTSA NCAP for estimating the risk of AIS>= 3 injuries to the head, neck, chest and AIS>=2 injury to the Knee-Thigh-Hip (KTH) complex has been conducted. The predicted injury risk to the four body regions based on driver dummy responses in over 300 frontal NCAP tests were compared against those to drivers involved in real-world crashes of similar severity as represented in the NASS.

The results of the study show that the predicted injury risks to the head and chest were slightly below those in NASS, and the predicted risk for the knee-thigh-hip complex was substantially below that observed in the NASS. The predicted risk for the neck by the Nij curve was greater than the observed risk in NASS by an order of magnitude due to the Nij risk curve predicting a non-zero risk when Nij = 0.

An alternative and published Nte risk curve produced a risk estimate consistent with the NASS estimate of neck injury. Similarly, an alternative and published chest injury risk curve produced a risk estimate that was within the bounds of the NASS estimates. No published risk curve for femur compressive load could be found that would give risk estimates consistent with the range of the NASS estimates. Additional work on developing a femur compressive load risk curve is recommended.

Dalmotas D, Prasad P, Augenstein J and Digges K; Assessing the field relevance of testing protocols and injury risk functions employed in new car assessment programs; Proc. 2010 IRCOBI Conf.; pp. 355; Hanover, Germany; September 15-16, 2010
Conference proceedings available from IRCOBI

Abstract: Over the past two decades the popularity of consumer crash test programs, commonly referred to as New Car Assessment Programs (NCAP), has grown across the world. They are popular among government regulators as they afford a means of promoting safety innovations and levels of vehicle performance beyond those dictated by national standards. They also fulfill the demand for information regarding the safety ranking of vehicles among consumers contemplating the purchase of a new vehicle.

There is no question that consumer crash test programs greatly influence vehicle design changes as well as accelerate the fitment of new safety features. The extent to which these changes can be expected to reduce serious and potentially fatal injuries will be influenced by how well the testing protocols and associated rating schemes correctly reflect the nature of the residual safety problem they seek to address.

Drawing on data contained primarily in the US National Automotive Sampling System (NASS), the field relevance of current and proposed testing and rating protocols addressing frontal crash test protection is examined. Emphasis is placed on examining how accurately injury rates computed from the dummy responses measured in consumer crash tests correspond to actual injury rates observed in the field. Additional data from Canadian field investigations and US databases such as the National Motor Vehicle Crash Causation Survey (NMVCCS) are examined to see how well frontal airbag firing times, crush pulse durations and other determinants of injury are replicated in consumer testing protocols. This portion of the analysis draws on data obtained from Event Data Recorders (EDR) in both field collisions and staged tests of the same vehicle model.

Vehicle rankings and overall frontal crash test ratings were found to be particularly sensitive to the choice of injury risk functions employed in the test. This was particularly true in the case of injury risk functions used to assess neck injury potential. Neck injury risk derived from Nij was found to show the least agreement with the field. Agreement between field chest injury rates and those derived from crash tests was improved considerably when chest injury risk functions for "older" occupants were employed. The paper concludes with a discussion of how different current testing protocols could be improved to enhance their field relevance.

D. C. Viano, C. Parenteau, P. Prasad and R. Burnett: Occupant Responses in High Speed Rear Crashes: Analysis of Government Sponsored Tests, SAE Paper No. 2008-08-0188, International Congress 2008.
Full-text paper available from SAE

Abstract:

The objective of this study was to analyze available anthropomorphic test device (ATD) responses from FMVSS 301-type rear impact tests. Rear impact test data was obtained from NHTSA and consisted of dummy responses, test observations, photos and videos. The data was organized in four test series: 1) NCAP series of 30 New Car Assessment Program tests carried out at 35 mph with 1979-1980 model year vehicles, 2) Mobility series of 14 FMVSS 301 tests carried out at 30 mph with 1993 model year vehicles, 3) 301 MY 95+ series of 79 FMVSS 301 tests carried out at 30 mph with 1995-2005 model year vehicles and 4) ODB series of 17 Offset Deformable Barrier tests carried out at 50 mph with a 70% overlap using 1996-1999 model year vehicles.

The results indicate very good occupant performance in yielding seats in the NCAP, Mobility and 301 MY 95+ test series. When the dummy responses were normalized by injury assessment reference values (IARVs), the largest normalized responses were 39.5% \mP 27.2% (average \mP standard deviation) for head acceleration and 46.6% \mP 27.0% for chest acceleration in the passenger NCAP series. The tests demonstrate occupant retention on the seat with the lap-shoulder-belted dummy and low risks of injury to the head, neck and chest. The yielding seats rotate rearward in the high-speed crashes and provide occupant protection. Dummy responses were higher in the more severe ODB series. The average normalized HIC was 98.3% \mP 59.4% for the near-side dummy and 105.4% \mP 77.5% for the far-side dummy. The largest normalized neck response was the lower-neck extension moment at 117.7% \mP 79.6% for the near-side dummy and 96.7% \mP 47.5% for the far-side dummy.

The dummy responses and kinematics in the 301-type rigid barrier tests are consistent with the very low risk of severe injury (MAIS 4+) in rear-impact field accidents. NASS-CDS data shows a risk of only 0.26% \mP 0.13% for MAIS 4+ injury in 20-25 mph rear delta V crashes and 0.19% \mP 0.13% in 25-30 mph delta V crashes.

The NHTSA crash tests and field accident data show that yielding seats of varying strength provide occupant protection in high-speed rear impacts.

S.-T. Hong, J. Pan, T. Tyan and P. Prasad: Dynamic Crush Behaviors of Aluminum Honeycomb Specimens under out of plane inclined loads. International Journal of Plasticity, Vol. 24, 2008, pp. 89-117.
Full-text paper available from Elsevier Ltd

Abstract:

The dynamic crush behaviors of aluminum 5052-H38 honeycomb specimens under compression dominant inclined loads are investigated by experiments. Different types of honeycomb specimens were designed for crush tests under pure compressive and compression dominant inclined loads with respect to the out-of-plane direction. A test fixture was designed for dynamic crush tests under inclined loads. The results of the dynamic crush tests indicate that as the impact velocity increases, the normal crush strength increases and the shear strength remains nearly the same. The trends of the normalized normal crush strengths under inclined loads for specimens with different in-plane orientation angles as functions of the impact velocity are very similar to each other. Based on the experimental results, a macroscopic yield criterion as a function of the impact velocity is proposed. The experimental results suggest that, as the impact velocity increases, the shape of the macroscopic yield surface changes, or more specifically, the curvature of the yield surface increases near the pure compression state. The experimental results also show similar microscopic progressive folding mechanisms in honeycomb specimens under pure compressive and inclined loads. However, honeycomb specimens under inclined loads show inclined stacking patterns of folds due to the asymmetric location of horizontal plastic hinge lines.

S.-T. Hong, J. Pan, T. Tyan and P. Prasad: A Comparison of Two Crush Test Methods for Honeycombs under Compression and Shear. Journal of Testing and Evaluation, Volume 36, Issue 4, 2008.
Full-text paper available from ASTM

Abstract:

Two different crush test methods for aluminum honeycombs under compression and shear loads with respect to the out-of-plane direction are presented in this paper. The honeycomb specimen geometry and the test fixtures for the two test methods are first presented. The combined load method used a test frame with two actuators and the inclined load method employed a multiaxial load cell. The experimental results obtained from the two test methods are presented. The experimental results in terms of the normal crush and shear strengths obtained from the combined and inclined load methods are quite consistent. The experimental results also indicate that under inclined loads, neglecting the constraint force can result in significant error, and the error due to the negligence of the constraint force becomes more pronounced as the inclined loading angle and the in-plane orientation angle increase.

P. Prasad, L. W. Schneider and W. Hardy: Interactions of Out-of-Position Small-female Surrogates with a Depowered Driver Airbag, 52nd Stapp Car Crash Conference Journal, 2008.
Full-text paper available from SAE

Abstract:

The objectives of this study were to examine the response, repeatability, and injury predictive ability of the Hybrid III small-female dummy to static out-of-position (OOP) deployments using a depowered driver-side airbag. Five dummy tests were conducted in two OOP configurations by two different laboratories. The OOP configurations were nose-on-rim (NOR) and chest-on-bag (COB). Four cadaver tests were conducted using unembalmed small-female cadavers and the same airbags used in the dummy tests under similar OOP conditions. One cadaver test was designed to increase airbag loading of the face and neck (a forehead-on-rim, or FOR test). Comparison between the dummy tests of Lab 1 and of Lab 2 indicated the test conditions and results were repeatable. In the cadaver tests no skull fractures or neck injuries occurred. However, all four cadavers had multiple rib fractures. These results suggested that an older, osteoporatic, small-female driver would experience AIS > or = 3 thoracic injury if exposed to this type of depowered airbag inflation for the three positions tested, but would be unlikely to experience any head or neck injury. The cadaver results provided no information about the possibility of AIS > or = 3 rib fractures for the average small, female driver. The Hybrid III small-female dummy results suggest that a low percentage (15%) of small, female drivers would experience AIS > or = 3 thoracic injuries if they had their chest on the module cover at the time of deployment of this depowered airbag. Also, for this position, the dummy results indicated a risk of an AIS = 2 neck injury for some small, female drivers. For all positions tested, the dummy results predicted that head injury was unlikely for most small-female drivers.

J. S. Ruan, R. El-Jawahri, S. D. Barbat, S. W. Rouhana and P. Prasad: Impact Response and Biomechanical Analysis of the Knee-Thigh-Hip Complex in Frontal Impacts With a Full Human Body Finite Element Model, 52nd Stapp Car Crash Conference Journal, 2008.
Full-text paper available from SAE

Abstract:

Changes in vehicle safety design technology and the increasing use of seat-belts and airbag restraint systems have gradually changed the relative proportion of lower extremity injuries. These changes in real-world injuries have renewed interest and the need of further investigation into occupant injury mechanisms and biomechanical impact responses of the knee-thigh-hip complex during frontal impacts.

This study uses a detailed finite element model of the human body to simulate occupant knee impacts experienced in frontal crashes. The human body model includes detailed anatomical features of the head, neck, shoulder, chest, thoracic and lumbar spine, abdomen, pelvis, and lower and upper extremities. The material properties used in the model for each anatomic part of the human body were obtained from test data reported in the literature. The human body model used in the current study has been previously validated in frontal and side impacts. It was further validated with cadaver knee-thigh-hip impact tests in the current study.

The effects of impactor configuration and flexion angle of the knee on biomechanical impact responses of the knee-thigh-hip complex were studied using the validated human body finite element model. This study showed that the knee flexion angle and the impact direction and shape of the impactors affected the injury outcomes of the knee-thigh-hip complex significantly. The 600 flexed knee impact showed the least impact force, knee pressure, femoral von Mises stress, and pelvic von Mises stress but largest relative displacements of the Posterior Cruciate Ligament (PCL) and Anterior Cruciate Ligament (ACL). The 900 flexed knee impact resulted in a higher impact force, knee pressure, femoral von Mises stress, and pelvic von Mises stress; but smaller PCL and ACL displacements. Stress distributions of the patella, femur, and pelvis were also given for all the simulated conditions.

In the archives:

C.L. Ewing, A.I. King, P. Prasad and A.P. Vulcan: A Method for Increasing the Threshold Level for Vertebral Fracture Due to +Gz Impact Acceleration. Proc. Of the 9th International Conference on Medical and Biological Engineering, 1971.

P. Prasad, A.I. King and C.L. Ewing: The Role of the Articular Facets During +Gz Acceleration. Proc. of the 25th Conference on Engineering in Medicine and Biology, 1972.

A.I. King, P. Prasad and P.C. Begeman: Spinal Responses to Forward Deceleration. Proc. of the 3rd All-India Symposium on Biomedical Engineering, 1972.

C.L. Ewing, A.I. King and P. Prasad: Structural Considerations of the Human Vertebral Column Under +Gz Impact Acceleration. Journal of Aircraft, 1972.

P.C. Begeman, A.I. King and P. Prasad: Spinal Loads Resulting from -Gx Acceleration. Proc. of the 10th International Conference on Medical and Biological Engineering, 1973.

P. Prasad: The Dynamic Response of the Spine During +Gz Acceleration. Ph.D. Dissertation, Wayne State University, Detroit, 1973.

P. Prasad, A.I. King, R.A. Denton and P.C. Begeman: Intervertebral Force Transducer. Proc. of the 10th International Conference on Medical and Biological Engineering, 1973.

P. Prasad, A.I. King and C.L. Ewing: The Role of Articular Facets during +Gz Acceleration. Journal of Applied Mechanics, 1974.

P. Prasad, A.I. King and C.L. Ewing: An Experimentally Validated Dynamic Model of the Spine. Journal of Applied Mechanics, 1974.

A.I. King, P. Prasad and C.L. Ewing: Mechanism of Spinal Injury Due to Candocephalad Acceleration. Proc. of the Orthopedic Clinics of North America, 1975.

P. Prasad, N.K. Mital, A.I. King and L.M. Patrick: Dynamic Response of the Spine During +Gx Acceleration. Proc. of the 19th Stapp Car Crash Conference, 1975.

A.J. Padgaonkar and P. Prasad: Simulation of Side Impact Using the CAL3D Occupant Simulation Model. Proc. of the 23rd Stapp Car Crash Conference , 1979.

P. Prasad, A.J. Padgaonkar: Static-to-Dynamic Amplification Factors for Use in Lumped-Mass Vehicle Crash Models. SAE810475, International Congress, February, 1981.

A.J. Padgaonkar and P. Prasad: A Mathematical Analysis of Side Impact Using the CAL3D Simulation Model. Proc. of the 9th International ESV Conference, 1982.

R.P. Daniel, M.S. Koga, P. Prasad and C.D. Yost: A Force Measuring Mechanical Device for Estimating and Comparing the Energy Absorbing Characteristics of Vehicle Interior Side Panels. Proc. of the 9th International ESV Conference, 1982.

P. Prasad: An Overview of Major Occupant Simulation Models. SAE 840855, SP-146, 1984. R.P. Daniel, P. Prasad and CD. Yost: A Biomechanical Evaluation of the Ford Side Impact Body Block and the SID/APR Side Impact Dummies. SAE 840882, International Congress, 1984.

P. Prasad and R.P. Daniel: A Biomechanical Analysis of Head, Neck and Torso Injuries to Child Surrogates Due to Sudden Torso Acceleration. Proc. of the 28th Stapp Car Crash Conference, 1984.

P. Prasad and H.S. Mertz: The position of the U.S. Delegation to ISO Working Group 6 on the Use if HIC in the Automotive Environment, SAE Paper No. 851246, 1985.

P. Prasad: Comparative Evaluation of the MVMA2D and the MADYMO2D Occupant Simulation Models with MADYMO Test Comparisons. Proc. of the 10th International Conference of the ESV, Oxford, U.K. 1985.

P. Prasad, J.W. Melvin, D.E. Huelke, A.I. King and G.W. Nyquist: Head-Review of Biomechanical Impact Response and Injury in the Automotive Environment. UMTRI Ed. Melvin and Weber, 1985.

P. Prasad and C.C. Chou: A Review of Mathematical Occupant Simulation Models. Proc. of the ASME Annual Conference, 1989.

P. Prasad: Comparative Evaluation of the Dynamic Responses of the Hybrid II and the Hybrid III Dummies. Proc. of the 34th Stapp Car Crash Conference. 1990.

T.C. Low and P. Prasad: Dynamic Response and Mathematical Model of the Side Impact Dummy. Proc. of 34th Stapp Car Crash Conference, 1990.

P.C. Begeman and P. Prasad: Human Ankle Impact Response in Dorsiflexion. Proc. of the 34th Stapp Conference, 1990.

P. Prasad, T.C. Low, C.C. Chou, G.G. Lim and S. Sundararajan: Side Impact Modeling Using Quasi-Static Crush Data, SAE Paper, International Congress, 1991.

T.C. Low, P. Prasad, G.G. Lim, C.C. Chou and S. Sundararajan: A MADYMO3D Side Impact Simulation Model. Proc. of the ASME Annual Conference, 1991.

L.P. Nolte, H. Visarius, P.C. Begeman and P. Prasad: Isolated Viscoelastic Shear Properties of the Human Lumbar Spine in Direct Shear. The ASME BED-Vol. 24, June 25-29, 1993.

L.P. Nolte, H. Visarius, P.C. Begeman and P. Prasad: Isolated Viscoelastic Shear Properties of the Human Lumbar Spine, Proc. of 3rd Injury Prevention Through Biomechanics Symposium, May 20-23, 1993. Sponsored by CDC, Wayne State University Press.

P. Prasad and C.C. Chou: A Review of Mathematical Occupant Simulation Models, Chapter 6, Accidental Injury - Biomechanics and Prevention. Edited by A.M. Nahum, A.M. and J.W. Melvin, Springer-Vertag, New York. 1993.

C. C. Chou, S. Neriya, T.C. Low and P. Prasad: MADYMO2D/3D Vehicle Structural/Occupant Simulation Models, AMD Volume 169/BED Volume 25, Crashworthiness and Occupant Protection in Transportation Systems, ASME 1993.

D.E. Midoun, D.M. Johnson, M.K. Rao and P. Prasad: Hybrid Modeling for Frontal Impact Into a Rigid Barrier. Proc. of International Body Engineering Conference, September 21-23, 1993. Detroit, MI.

J. Ruan and P. Prasad: Head Injury Potential Assessment in Frontal Impact by Mathematical Modeling. Proc. of 38th Stapp Car Crash Conference, SAE Paper No. 942212, 1994.

C. C. Chou, G G. Li, S. Sundararajan, T. C. Low, P. Prasad, J. O. Mitchell: Experimental Validation of Ellipsoid - To - Foam Contact Model, SAE Paper No. 9408881, SAE World Congress, 1994.

P.C. Begeman, H. Visarius, L.P. Nolte, P. Prasad: Viscoelastic Shear Responses of the Cadaver and Hybrid III Dummy. Proc. of 37th Stapp Car Crash Conference, 1994.

J. Ruan and P. Prasad: Coupling of a Finite Element Human Head Model with a Lumped Parameter Hybrid III Dummy Odel \u2013 Preliminary Results, Journal of Neurotrauma, Vol. 12, November 4, 1995.

P. Prasad and L. Smorgonsky: Comparative Evaluation of Various Frontal Impact Test Procedures, SAE 950646, International Congress, March 1995.

S. Barbat and P. Prasad: Finite Element Modeling of Structural Foam and Head Impact Interaction with Vehicle Upper Interior, SAE 950885, International Congress, March 1995.

N.K. Saha, S.M. Calso, P. Prasad and M.U. Asjad: Simulation of Frontal Barrier Offset Impacts and Comparison of Intrusions and Decelerations. SAE 950647, International Congress, March, 1995.

P. Krypton, U. Berleman, H. Visarius, P.C. Begeman, L.P. Nolte and P. Prasad: Response of the Lumbar Spine Due to Shear Loading. Proc. of the 5th Injury Prevention Through Biomechanics Symposium, Sponsored by CDC, Wayne State University, 1995.

S. D. Barbat and P. Prasad: Numerical Simulations and Predictions of Spot-Weld/Weld-Bond Separation in Aluminum Closed-Hat Sections in Axial Collapse. Proc. Of the Crashworthiness and Occupant Protection in Transportation Systems. AMD-Vol. 210/BED-Vol. 30, San Francisco, CA, 1995.

J. S. Ruan and P. Prasad: Prediction of Skull and Brain Stress (Strain) Utilizing a Human Head Model, ASME/AICH/ASCE Summer Bioengineering Conference, Beaver Creek, Colorado, June 28-July 2, 1995.

S. H. Backaitis, M.E. Hicks, P. Prasad, T. Laituri and J. Nadeau: Variability of Hybrid III Clearance Dimensions with FMVSS 208 and NCAP Vehicle Test Fleet and the Effects of Clearance Dimensions on Dummy Impact Responses, Proc. of the 39th Stapp Car Crash Conference, San Diego, California, November 8-10, 1995.

P. Prasad, T. R. Laituri: Consideration for Belted FMVSS 208 Testing. The 15th International Technical Conference on Enhanced Safety of Vehicles, Paper No. 96-S3-O-03, 1996.

N. Yoganandan, F. Pintar, M. Boynton, P. Begeman, P. Prasad, S.M. Kuppa, R.M. Morgan and R.H Eppinger: Dynamic Axial Tolerance of the Human Foot-Ankle Complex. Proc. of 40th Stapp Car Crash Conference SAE Paper No. 962426, 1996.

J. S. Ruan and P. Prasad: Study of the Biodynamic Characteristics of the Human Head, Proc. Of 1996 International IRCOBI Conference, pp. 63-74.

S. D. Barbat, H.Y. Jeong and P. Prasad: Finite Element Modeling and Development of the Deformable Featureless Headform and Its Application to Vehicle Interior Head Impact Tests. SAE Paper No. 960104, International Congress, February 1996.

H.J. Mertz, G. Nusholtz and P. Prasad: Head Injury Risk Assessment for Forehead Impacts. SAE Paper No. 960099, International Congress, March 1996.

G.G. Lim, C.C. Chou, S. Sundararajan, L.A. Walker, G. Fletcher and P. Prasad: Deployable Door Trim System for Side Impact Protection, An Addendum of the Proceedings of Automotive Body Interior and Safety Systems, Vol. 23, International Body Engineering Conference, October 1-3, 1996.

S.D. Barbat, H.F. Mahmood and P. Prasad: Aluminum Intensive Vehicle Crashworthiness Design Approach, Proceedings of the Crashworthiness, Occupant Protection and Biomechanics in Transportation Systems, AMD-Vol. 225/BED-Vol. 38, Dallas, Texas, 1997.

H.J. Mertz, P. Prasad and A. Irwin: Injury Risk Curves for Children and Adults in Frontal and Rear Collisions, 41st Stapp Car Crash Conference, SAE Paper No. 973318 November, 1997.

P. Prasad: Occupant Simulation Models: Experiment and Practice, Proc. Of Crashworthiness of Transportation Systems: Structural Impact and Occupant Protection, NATO ASI Series Vol. 332, 1997.

P. Prasad, A. Kim, D.P.V. Weerappuli: Biofidelity of Anthropomorphic Test Devices for Rear Impact, Proc. of 41st Stapp Crash Conference, SAE Paper No. 973342, 1997.

P. Prasad, A. Kim, D.P.V. Weerappuli, V. Roberts and D. Schneider: Relationships Between Passenger Car Seat Back Strength and Occupant Injury Severity in Rear End Collisions: Field and Laboratory Studies, Proc. of 41st Stapp Car Crash Conference, SAE Paper No. 973343, 1997.

N. Saha, S. Calso, D. Midoun and P. Prasad: Critical Comparison of U.S. and European Dynamic Side Impacts, SAE Congress and Exposition, SAE Paper No. 970128, 1997.

J.S. Ruan, P. Prasad and D. Weerappuli: A Study of the Influence of the Neck Restraint on the Human Head Impact Response, ASME/AICHE/ASCE Summer Bioengineering Conference, Sunriver, June 11-15, 1997.

J.S. Ruan and P. Prasad: Biomechanical Study of Head Injury through Finite Element Analysis. Invited chapter in Frontiers in Head and Neck Trauma \u2013 Clinical and Biomechanical, Editors. N. Yoganandan and F.A. Pintar, in print, 1998.

S.D. Barbat and P. Prasad: Design Analysis of Aluminum Exterior Body Panels for Crashworthiness Improvements, ASCE Conference, May 17, 1998.

A. Manoli, R.S. Levine and P. Prasad: Foot and Ankle Severity Scale, International Journal of the Foot and Ankle Society, 1998.

A. Jibril, P. Prasad, J. Prybylski, I. Parekh, E. S. Grush: Logistic Regression Analysis of Lower Limb Injuries in Frontal Crashes. 16th International Technical Conference on Experimental Safety Vehicles. Report No. 98-S6-W-43, 1998.

L. Chai, T. Subbian, A. Khan, S. Barbat, C. O'Conner, R. McCoy, P, Prasad: Finite Element Model Development of SID-IIs. 43rd Stapp Car Crash Conference. Paper No. SAE 99SC06, 1999.

P. Prasad, Biomechanical Basics for Injury Criteria Used in Crashworthiness Regulations, Bertil Aldman Award Lecture, Proc. of the IRCOBI Conference on the Biomechanics of Impact, 1999.

P. C. Begeman, K. Pratima, P. Prasad: Bending Strength of the Human Cadaveric Forearm Due to Lateral Loads. 43rd Stapp Car Crash Conference. Report No. SAE 99SC24, 1999.

T. R. Laituri, P. Prasad: Correlation of Drive Inflator Predictor Variables with the Viscous Criterion for the Mid-Sized Male, Instrumented Test Dummy in the Chest-on-Module Condition, SAE Paper No. 1999-01-0763, SAE International Congress, 1999.

D. P. Weerappuli, L. Chai, S. Barbat, D. Wan, P. Prasad: Development of a MADYMO3D Model of the SID-IIs Dummy. ASME, 1999.

P. Prasad: Role of Electronics in Automotive Safety. SAE Paper No. SAE 2000-01-C086, 2000. A. Kim, P. Prasad: Hybrid III and Hybrid III with a TRID Neck in Low Speed Rear Impacts, in Frontiers of Whiplash Trauma, Edited by N. Yoganandan and F. A. Pinter, ISO Press, 2000.

H. J. Mertz, P. Prasad: Improved Neck Injury Risk Curves for Tension and Extension Moment Measurements of Crash Dummies. Proc. of the 44th Stapp Car Crash Conference. Paper No. 2000-01-SC05, 2000.

P. J. Schuster, C. C. Chou, P. Prasad, G. Jayaraman: Development and Validation of a Pedestrian Lower Limb Non-Linear 3-D Finite Element Model. 44th Stapp Car Crash Conference. Report No. 2000-01-SC21, 2000.

T. Laituri, N. Sriram, B. Kachnowski, Bron Scheidel, P. Prasad: Theoretical Evaluation of the Requirements of the 1999 Advanced Airbag SNPRM - Part One: Design Space Constraint Analysis, SAE Paper No. 2001-01-0165, International Congress, 2001.

S. Barbat, X. Li, P. Prasad: Evaluation of Vehicle Compatibility in Various Frontal Impact Configurations. SAE Paper No. 2001-06-0097. International Technical Conference on the Enhanced Safety of Vehicles, Amsterdam, The Netherlands, 2001.

S. Barbat, X. Li, P. Prasad: A Comparative Analysis of Vehicle-to-Vehicle and Vehicle-to-Rigid Fixed Barrier Frontal Impacts. SAE Paper No. 2001-06-0031. International Technical Conference on the Enhanced Safety of Vehicles, Amsterdam, The Netherlands, 2001.

R. Kent, J. Bolton, J. Crandall, P. Prasad, G. Nusholtz, H. Mertz, D. Kallieris: Restrained Hybrid III Dummy-Based Criteria for Thoracic Hard Tissue Injury Prediction. SAE Paper No. 2001-13-0017. IRCOBI Conference, United Kingdom, 2001.

P. Beillas, P. Begeman, K. Yang, A. King, P-J Arnoux, H-S Kang, K. Kayvantash, C. Brunet, C. Cavallero, P. Prasad: Lower Limb: Advanced FE Model and New Experimental Data. 45th Stapp Car Crash Journal, 2001.

J. Ruan, P. Prasad: The Effects of Skull Thickness Variations on Human Head Dynamic Impact Responses. 45th Staff Car Crash Journal, 2001.

R. Kent, J. Crandall, J. Bolton, P. Prasad, G. Nusholtz, H. Mertz: The Influence of Superficial Soft Tissues and Restraint Condition on Thoracic Skeletal Injury Prediction. 45th Staff Car Crash Journal, 2001.

T. Dhaliwal, P. Beillas, C. Chou, P. Prasad, K. Yang, A. King: Structural Response of Lower Leg Muscles in Compression: A Low Impact Energy Study Employing Volunteers, Cadavers and the Hybrid III. 45th Stapp Car Crash Journal, 2001.

S.-H. Lin, J. Pan, T. Tyan, S. R. Wu and P. Prasad: Modeling and Testing of Spot Welds Under Dynamic Impact Loading Conditions, SAE Paper No. 2002-01-0149, SAE World Congress, 2002.

S.H. Lin, J. Pan. T. Tyan, P. Prasad: Failure Modeling of Spot Welds Under Complex Combined Loading Conditions for Crash Applications, SAE Paper No. 2002-01-2032. Intl. Body Engineering Conf. and Exhibition, 2002.

S.T. Hong, J. Pan, T. Tyan and P. Prasad: Influence of Shear Loads on Crush of Honeycomb Materials, SAE Paper No. 2002-01-0683. SAE World Congress, 2002.

T. S. Dhaliwal, P. Beillas, C. C. Chou, P. Prasad, K. H. Yang, A. I. King: Structural Response of Lower Leg Muscles in Compression: A Low Impact Energy Study Employing Volunteers, Cadavers and the Hybrid III, SAE Paper No. 2002-22-0012. 46th Stapp Car Crash Journal, 2002.

T. Laituri, B. Kachnowski, P. Prasad, K. Sullivan, P. Przybylo: Predictions of AIS3+ Thoracic Risks for Belted Occupants in Full Engagement, Real-World Frontal Impacts: Sensitivity to Various Theoretical Risk Curves. SAE Paper No. 2003-01-1355. World Congress, 2003.

S.-H. Lin, J. Pan, T. Tyan, P. Prasad: A General Failure Criterion for Spot Welds With Consideration of Plastic Anisotropy and Separation Speed, SAE Paper No. 2003-01-0611. SAE World Congress, 2003.

S. T. Hong, J. Pan, T. Tyan, P. Prasad: Crush Strength of Aluminum 5052-H38 Honeycomb Materials Under Combined Compressive and Shear Loads, SAE Paper No. 2003-01-0331. SAE World Congress, 2003.

T. Laituri, B. Kachnowski, P. Prasad, K. Sullivan, P. Przybylo: A Theoretical, Risk Assessment Procedure for In-Position Drivers Involved in Full-Engagement Frontal Impacts. SAE Paper No. 2003-01-1354. World Congress, 2003.

L. Wang, R. Banglmaier, P. Prasad: Injury Risk Assessment of Several Crash Data Sets. SAE Paper No. 2003-01-1214. World Congress, 2003.

S. D. Barbat, X. Li, P. Przybylo and P. Prasad: Vehicle-to-Vehicle Full Frontal Crash Optimization Using a CAE-Based Methodology, Proc. 18th ESV Conference, Nagoya, Japan. DOT HS809543, May 2003.

F. Heitzplatz, R. Sferco, P. Fay, J. Rheim, A. Kim and P. Prasad: An Evaluation of Existing and Proposed Injury Criteria with Various Dummies to Determine Their Ability to Predict the Levels of STNI seen in Real Accidents, Proc. 18th ESV Conference, Nagoya, Japan, DOT HS809543, May 2003.

S. Rouhana, P. Bedewi, S. Kankanala, P. Prasad, J. Zwolinski, A. Meduysky, J. Rupp, T. Jeffreys, L Schneider: Biomechanics of 4-Point Seat Belt Systems in Frontal Impacts. 47th Stapp Car Crash Journal, 2003.

J. Ruan, R. El-Jawahri, L. Chai, S. Barbat, P. Prasad: Prediction and Analysis of Human Thoracic Impact Responses and Injuries in Cadaver Impacts Using a Full Human Body Finite Element Model. 47th Stapp Car Crash Journal, 2003.

H Mertz, A. Irwin, P. Prasad: Biomechanical and Scaling Bases for Frontal and Side Impact Injury Assessment Reference Values. 47th Stapp Car Crash Journal, 2003.

T. Laituri, D. Sullivan, K. Sullivan, P. Prasad: A Theoretical Math Model for Projecting AIS3+ Thoracic Injury for Belted Occupants in frontal Impacts. 48th Stapp Car Crash Conference, Journal, November, 2004.

S. Sundararajan, P. Prasad, C.K. Demetropoulos, S. Tashman, P. C. Begeman, K. H. Yanbg, A. I. King: Effect of Head- Neck Position on Cervical Facet Stretch of Post Mortem Human Subjects During Low Speed, Rear-End Impacts, 48th Stapp Car Crash Journal, 2004.

S.T. Hong, J. Pan, T. Tyan, P. Prasad: Effects of Impact Velocity on Crush Behavior of Honeycomb Specimens, SAE Paper No. 2004-01-0245, SAE World Congress, 2004.

P. Prasad, T. Laituri, K. Sullivan: Estimation of AIS3+ Thoracic Injury Risks of Belted Drives in NASS Frontal Crashes, Journal of Automobile Engineering, 2004. Vol. 218, No. D6. IMechE, United Kingdom.

P. Weerappuli, P. Prasad, S. Barbat: Effectiveness of the Head and Neck Support (HANS©) Device in Frontal Impacts of CART Carts: A CAE Analysis. International Journal of Vehicle Safety. Volume 1, January, 2005.

T. Laituri, P. Prasad, K. Sullivan, M. Frankstein, R. Thomas: Derivation and Evaluation of a Provisional, Age-Dependent, AIS3+ Thoracic Risk Curve for Belted Occupants in Frontal Impacts, SAE 2005-01-0297. April, 2005.

J. Ruan, R. El-Jawahri, S. Barbat, P. Prasad: Pelvic Impact Response and Injury Simulation using a Full Human Body Finite Element Model. Proceedings of NAFEMS World Congress. May, 2005 J. Ruan, R. El-Jawahri, S. Barbat, P. Prasad: Biomechanical Analysis of Human Abdominal Impact Responses and Injuries through Finite Element simulations of a Full Human Body Model. 49th Stapp Car Crash Conference Journal, November, 2005.

S. Sundararajan, P. Prasad, S. Rouhana, C. Demetropoulos, , K. Yang, A. King: Characteristics of PMHS Lumbar Motion Segments in Lateral Shear. 49th Stapp Car Crash Conference Journal, November, 2005.

S-T. Hong, J. Pan, T. Tyan, P. Prasad: Honeycomb Specimens Under Combined Compressive and Shear Displacement Conditions, SAE Paper No. 2005-01-0360, International Congress, 2005.

R. Banglmaier, L. Wang, P. Prasad: Influence of Interval Censoring and Bias on Injury Risk Curve Development. International Journal of Materials and Product Technology; Vol. 25, No. 1-3; pp. 42 – 63; 2006.

T. R. Laituri, S. Henry, K. Sullivan, P. Prasad: Derivation and Theoretical Assessment of a Set of Biomechanics-based, AIS2+ Risk Equations for the Knee-Thigh-Hip Complex, 50th Stapp Car Crash Conference Journal, November 2006.

J. Forman, D. Lessley, C. G. Shaw, J. Evans, R. Kent, S. W. Rouhana, P. Prasad: Thoracic Response of Belted PMHS, Hybrid III, and the THOR-NT Mid-Sized Male Surrogates in Low Speed, Frontal Crashes, 50th Stapp Car Crash Conference Journal, November, 2006.

S. W. Rouhana, S. V. Kankanala, P. Prasad, J. D. Rupp, T. A. Jeffreys, L. A. Schneider: Biomechanics of 4-point Seat Belt Systems in Farside Impacts, 50th Stapp Car Crash Conference Journal, 2006.

K. H. Yang, J. Hu, N. A. White, A. I. King, C. C. Chou: Development of Numerical Models for Biomechanical Research: A Review of 50 Years of Publication in the Stapp Car Crash Conference, 50th Stapp Car Crash Conference Journal, 2006.

J. S. Ruan, R. El-Jawahri, S. W. Rouhana, S. D. Barbat and P. Prasad: Analysis and Evaluation of the Biofidelity of the Human Body Finite Element Model in Lateral Impact Simulations According to ISO-TR9790 Procedures, 50th Stapp Car Crash Conference Journal, 2006.

S.-T. Hong, J. Pan, T. Tyan and P. Prasad: Quasi-Static Crush Behavior of Aluminum Honeycomb Specimens under Non-Proportional Compression Dominant Combined Loads. International Journal of Plasticity, Vol. 22, 2006, pp.1062-1088.

S.-T. Hong, J. Pan, T. Tyan and P. Prasad: Quasi-Static Crush Behavior of Aluminum Honeycomb Specimens under Compression Dominant Combined Loads. International Journal of Plasticity, Vol. 22, 2006, pp.73-109.

J. S. Ruan and P. Prasad: The Influence of Human Head Tissue Properties on Intracranial Pressure Response During Direct Head Impact, Intl. Journal of Vehicle Safety, 1(4):282-291, 2006.

V.-X. Tran, S.-T. Hong, J. Pan, T. Tyan and P. Prasad: Crush Behaviors of Aluminum Honeycombs of Different Cell Geometries under Compression Dominant Combined Loads, SAE Transactions, Journal of Materials and Manufacturing, 2007, pp. 163-170.

D. C. Viano, C. Parenteau, P. Prasad and R. Burnett: Stiff versus Yielding Seats: Analysis of Matched Rear Impact Tests, SAE Paper No. 2007-01-0708, International Congress, 2007.

S. D. Barbat, X. Li and P. Prasad: Vehicle-to-Vehicle Front-to-Side Crash Analysis Using a CAE-based Methodology, Proc. 20th ESV Conference, Paper no. 07-0347, Lyon, France, June 2007.

S.D. Barbat, X. Li, S. Reagan and P. Prasad: Vehicle Compatibility Assessment Using Test Data of Full Frontal Vehicle-to-Vehicle and Vehicle-to-Full Width Deformable Barrier Impacts, Proc. 20th ESV Conference, paper no. 07-0348, Lyon, France, June 2007.

S.-T. Hong, J. Pan, T. Tyan and P. Prasad: Macroscopic Constitutive Behaviors of Aluminum Honeycombs under Dynamic Inclined Loads, 2007 SAE Transactions, Journal of Material and Manufacturing, 2007.

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