Whyte, Thomas; Gibson, Tom; Anderson, Robert; Eager, David; Milthorpe, Bruce
Mechanisms of head and neck injuries sustained by helmeted motorcyclists in fatal real-world crashes: Analysis of 47 in-depth cases Journal Article
In: Journal of Neurotrauma, vol. 33, no. 19, pp. 1802–1807, 2016, ISBN: 0897-7151 1557-9042.
Abstract | Links | BibTeX | Tags: 2016, BRAIN damage, Head Injuries, Helmet, mechanisms, Motor Vehicles, motorcyclist, Safety devices, traumatic injury
@article{Whyte2016,
title = {Mechanisms of head and neck injuries sustained by helmeted motorcyclists in fatal real-world crashes: Analysis of 47 in-depth cases},
author = {Whyte, Thomas and Gibson, Tom and Anderson, Robert and Eager, David and Milthorpe, Bruce},
doi = {10.1089/neu.2015.4208},
isbn = {0897-7151
1557-9042},
year = {2016},
date = {2016-01-01},
journal = {Journal of Neurotrauma},
volume = {33},
number = {19},
pages = {1802--1807},
publisher = {Mary Ann Liebert, Inc.},
address = {US},
abstract = {Despite an improved understanding of traumatic head and neck injury mechanisms, the impact tests required by major motorcycle helmet standards have remained unchanged for decades. Development of new test methods must reflect the specific impact loads causing injury in real crashes as well as test criteria appropriate for the observed injury profiles. This study analysed a collection of in-depth crash investigations of fatally injured helmeted riders in the Adelaide metropolitan region between 1983 and 1994 inclusive to review the head and neck injury patterns that resulted from specific types of impact. Inertial brain injury was sustained in 49% of examined cases, most often resulting from facial impacts but also in a large proportion of tangential, run over, and occipital impact cases. Focal brain and brainstem injury was also common (53%) and regularly associated with skull vault (11/12) and skull base fractures (22/31). Prevention of these fractures in impacts outside the area of required protection and in impacts with a straight edge would provide a significant increase in helmeted rider protection. Cervical spinal cord injury was sustained in facial, straight edge, and tangential impacts on the head. Motorcycle helmets are effective for preventing local skull fractures in impacts for which they are designed, whereas other serious injuries such as basilar skull fracture (BSF) and inertial brain injury persist despite helmet protection. Further impact test procedures should be developed for injurious impact types not currently assessed by major helmet standards, in particular facial impacts, and using test criteria based on commonly observed injuries. This study provides the necessary link, from impact load to injury, for guiding impact test development. (PsycINFO Database Record (c) 2016 APA, all rights reserved)},
keywords = {2016, BRAIN damage, Head Injuries, Helmet, mechanisms, Motor Vehicles, motorcyclist, Safety devices, traumatic injury},
pubstate = {published},
tppubtype = {article}
}
Cobb, B R; Zadnik, A M; Rowson, S
Comparative analysis of helmeted impact response of Hybrid III and National Operating Committee on Standards for Athletic Equipment headforms Journal Article
In: Proceedings of the Institution of Mechanical Engineers, Part P: Journal of Sports Engineering and Technology, vol. 230, no. 1, pp. 50–60, 2016.
Abstract | Links | BibTeX | Tags: Acceleration, Accident prevention, Angular acceleration, Biomechanics, Brain Injury, Coefficient of variation values, Comparative analysis, Concussion, Equipment, Evaluation protocol, helmet testing, Linear acceleration, Linear accelerations, Rotational acceleration, Safety devices, Sporting goods, standards
@article{Cobb2016,
title = {Comparative analysis of helmeted impact response of Hybrid III and National Operating Committee on Standards for Athletic Equipment headforms},
author = {Cobb, B R and Zadnik, A M and Rowson, S},
doi = {10.1177/1754337115599133},
year = {2016},
date = {2016-01-01},
journal = {Proceedings of the Institution of Mechanical Engineers, Part P: Journal of Sports Engineering and Technology},
volume = {230},
number = {1},
pages = {50--60},
abstract = {As advanced helmet testing methodologies are developed, the effect headform selection may have on the biomechanical impact response must be considered. This study sought to assess response differences between two of the most commonly used headforms, the Hybrid III and National Operating Committee on Standards for Athletic Equipment headforms, through a series of helmeted impact tests. A total of 180 pendulum impact tests were conducted with three impactor velocities and six impact locations. Test condition-specific significant differences were found between the two headforms for peak linear and angular accelerations ($alpha$ = 0.05), although differences tended to be small. On average, the National Operating Committee on Standards for Athletic Equipment headform experienced higher peak linear (3.7 ± 7.8%) and angular (12.0 ± 21.6%) accelerations, with some of the largest differences associated with impacts to the facemask. Without the facemask impacts, the average differences in linear (1.8 ± 6.0%) and angular (9.6 ± 15.9%) acceleration would be lower. No significant differences were found in coefficient of variation values for linear (Hybrid III: 2.6 ± 2.3%, National Operating Committee on Standards for Athletic Equipment: 2.0 ± 1.4%) or angular (Hybrid III: 4.9 ± 4.0%; National Operating Committee on Standards for Athletic Equipment: 5.2 ± 5.8%) acceleration. These data have application toward development and validation of future helmet evaluation protocols and standards. © IMechE 2015.},
keywords = {Acceleration, Accident prevention, Angular acceleration, Biomechanics, Brain Injury, Coefficient of variation values, Comparative analysis, Concussion, Equipment, Evaluation protocol, helmet testing, Linear acceleration, Linear accelerations, Rotational acceleration, Safety devices, Sporting goods, standards},
pubstate = {published},
tppubtype = {article}
}
Johnson, K L; Chowdhury, S; Lawrimore, W B; Mao, Y; Mehmani, A; Prabhu, R; Rush, G A; Horstemeyer, M F
Constrained topological optimization of a football helmet facemask based on brain response Journal Article
In: Materials and Design, vol. 111, pp. 108–118, 2016.
Abstract | Links | BibTeX | Tags: Accident prevention, ALGORITHMS, brain, Concussion, Constrained optimization, Design, Design optimization, finite element analysis, Finite element method, football helmet, Fuel additives, Genetic algorithms, Multiobjective optimization, Optimization, Safety devices, Shear strain, Sports, Surrogate model, Surrogate modeling, Topology, Traumatic Brain Injuries, traumatic brain injury
@article{Johnson2016a,
title = {Constrained topological optimization of a football helmet facemask based on brain response},
author = {Johnson, K L and Chowdhury, S and Lawrimore, W B and Mao, Y and Mehmani, A and Prabhu, R and Rush, G A and Horstemeyer, M F},
doi = {10.1016/j.matdes.2016.08.064},
year = {2016},
date = {2016-01-01},
journal = {Materials and Design},
volume = {111},
pages = {108--118},
abstract = {Surrogate model-based multi-objective design optimization was performed to reduce concussion risk during frontal football helmet impacts. In particular, a topological decomposition of the football helmet facemask was performed to formulate the design problem, and brain injury metrics were exploited as objective functions. A validated finite element model of a helmeted human head was used to recreate facemask impacts. Due to the prohibitive computational expense of the full scale simulations, a surrogate modeling approach was employed. An optimal surrogate model selection framework, called Concurrent Surrogate Model Selection, or COSMOS, was utilized to identify the surrogate models best suited to approximate each objective function. The resulting surrogate models were implemented in the Non-dominated Sorting Genetic Algorithm II (NSGA-II) optimization algorithm. Constraints were implemented to control the solid material fraction in the facemask design space, and binary variables were used to control the placement of the facemask bars. The optimized facemask designs reduced the maximum tensile pressure in the brain by 7.5% and the maximum shear strain by a remarkable 39.5%. This research represents a first-of-its-kind approach to multi-objective design optimization on a football helmet, and demonstrates the possibilities that are achievable in improving human safety by using such a simulation-based design optimization. © 2016 Elsevier Ltd},
keywords = {Accident prevention, ALGORITHMS, brain, Concussion, Constrained optimization, Design, Design optimization, finite element analysis, Finite element method, football helmet, Fuel additives, Genetic algorithms, Multiobjective optimization, Optimization, Safety devices, Shear strain, Sports, Surrogate model, Surrogate modeling, Topology, Traumatic Brain Injuries, traumatic brain injury},
pubstate = {published},
tppubtype = {article}
}
Bowman, T G; Breedlove, K M; Breedlove, E L; Dodge, T M; Nauman, E A
Impact attenuation properties of new and used lacrosse helmets Journal Article
In: Journal of Biomechanics, vol. 48, no. 14, pp. 3782–3787, 2015.
Abstract | Links | BibTeX | Tags: Accident prevention, Article, Athletic Injuries, attenuation, brain concussion, Cracks, Drop test, Drops, Equipment Design, Gadd Severity Index, head impact, Head Protective Devices, Helmet, Helmet evaluation, human, Humans, Injuries, lacrosse helmet, Materials testing, mechanical stress, priority journal, protective equipment, racquet sport, Racquet Sports, recertification, rigidity, Safety devices, Severity index, Sporting goods, Sports Equipment, standards, stress strain relationship, velocity
@article{Bowman2015,
title = {Impact attenuation properties of new and used lacrosse helmets},
author = {Bowman, T G and Breedlove, K M and Breedlove, E L and Dodge, T M and Nauman, E A},
doi = {10.1016/j.jbiomech.2015.08.026},
year = {2015},
date = {2015-01-01},
journal = {Journal of Biomechanics},
volume = {48},
number = {14},
pages = {3782--3787},
abstract = {The National Operating Committee on Standards for Athletic Equipment (NOCSAE) has developed impact attenuation thresholds that protective helmets worn in sport must meet to be commercially available in an attempt to prevent injury. It remains unknown how normal helmet use in athletic activity alters the force attenuation ability of lacrosse helmets. We tested 3 new and 3 randomly selected used helmets from 2 popular lacrosse models (Cascade Pro7, Cascade CPXR). All used helmets had been worn for 3 collegiate seasons prior to testing and had never been refurbished. Helmets were drop-tested using 3 prescribed impact velocities at 6 locations according to the NOCSAE lacrosse helmet standard, and we compared the Gadd Severity Index (GSI) scores between new and used helmets using a repeated measure ANOVA with location as the repeated variable and data separated by impact velocity. All 12 helmets passed the NOCSAE GSI threshold for all testing conditions; however 1 used helmet shell cracked resulting in a failed test. We found a significant main effect for helmet age at the low (F5},
keywords = {Accident prevention, Article, Athletic Injuries, attenuation, brain concussion, Cracks, Drop test, Drops, Equipment Design, Gadd Severity Index, head impact, Head Protective Devices, Helmet, Helmet evaluation, human, Humans, Injuries, lacrosse helmet, Materials testing, mechanical stress, priority journal, protective equipment, racquet sport, Racquet Sports, recertification, rigidity, Safety devices, Severity index, Sporting goods, Sports Equipment, standards, stress strain relationship, velocity},
pubstate = {published},
tppubtype = {article}
}
Whyte, Thomas; Gibson, Tom; Anderson, Robert; Eager, David; Milthorpe, Bruce
Mechanisms of head and neck injuries sustained by helmeted motorcyclists in fatal real-world crashes: Analysis of 47 in-depth cases Journal Article
In: Journal of Neurotrauma, vol. 33, no. 19, pp. 1802–1807, 2016, ISBN: 0897-7151 1557-9042.
@article{Whyte2016,
title = {Mechanisms of head and neck injuries sustained by helmeted motorcyclists in fatal real-world crashes: Analysis of 47 in-depth cases},
author = {Whyte, Thomas and Gibson, Tom and Anderson, Robert and Eager, David and Milthorpe, Bruce},
doi = {10.1089/neu.2015.4208},
isbn = {0897-7151
1557-9042},
year = {2016},
date = {2016-01-01},
journal = {Journal of Neurotrauma},
volume = {33},
number = {19},
pages = {1802--1807},
publisher = {Mary Ann Liebert, Inc.},
address = {US},
abstract = {Despite an improved understanding of traumatic head and neck injury mechanisms, the impact tests required by major motorcycle helmet standards have remained unchanged for decades. Development of new test methods must reflect the specific impact loads causing injury in real crashes as well as test criteria appropriate for the observed injury profiles. This study analysed a collection of in-depth crash investigations of fatally injured helmeted riders in the Adelaide metropolitan region between 1983 and 1994 inclusive to review the head and neck injury patterns that resulted from specific types of impact. Inertial brain injury was sustained in 49% of examined cases, most often resulting from facial impacts but also in a large proportion of tangential, run over, and occipital impact cases. Focal brain and brainstem injury was also common (53%) and regularly associated with skull vault (11/12) and skull base fractures (22/31). Prevention of these fractures in impacts outside the area of required protection and in impacts with a straight edge would provide a significant increase in helmeted rider protection. Cervical spinal cord injury was sustained in facial, straight edge, and tangential impacts on the head. Motorcycle helmets are effective for preventing local skull fractures in impacts for which they are designed, whereas other serious injuries such as basilar skull fracture (BSF) and inertial brain injury persist despite helmet protection. Further impact test procedures should be developed for injurious impact types not currently assessed by major helmet standards, in particular facial impacts, and using test criteria based on commonly observed injuries. This study provides the necessary link, from impact load to injury, for guiding impact test development. (PsycINFO Database Record (c) 2016 APA, all rights reserved)},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Cobb, B R; Zadnik, A M; Rowson, S
Comparative analysis of helmeted impact response of Hybrid III and National Operating Committee on Standards for Athletic Equipment headforms Journal Article
In: Proceedings of the Institution of Mechanical Engineers, Part P: Journal of Sports Engineering and Technology, vol. 230, no. 1, pp. 50–60, 2016.
@article{Cobb2016,
title = {Comparative analysis of helmeted impact response of Hybrid III and National Operating Committee on Standards for Athletic Equipment headforms},
author = {Cobb, B R and Zadnik, A M and Rowson, S},
doi = {10.1177/1754337115599133},
year = {2016},
date = {2016-01-01},
journal = {Proceedings of the Institution of Mechanical Engineers, Part P: Journal of Sports Engineering and Technology},
volume = {230},
number = {1},
pages = {50--60},
abstract = {As advanced helmet testing methodologies are developed, the effect headform selection may have on the biomechanical impact response must be considered. This study sought to assess response differences between two of the most commonly used headforms, the Hybrid III and National Operating Committee on Standards for Athletic Equipment headforms, through a series of helmeted impact tests. A total of 180 pendulum impact tests were conducted with three impactor velocities and six impact locations. Test condition-specific significant differences were found between the two headforms for peak linear and angular accelerations ($alpha$ = 0.05), although differences tended to be small. On average, the National Operating Committee on Standards for Athletic Equipment headform experienced higher peak linear (3.7 ± 7.8%) and angular (12.0 ± 21.6%) accelerations, with some of the largest differences associated with impacts to the facemask. Without the facemask impacts, the average differences in linear (1.8 ± 6.0%) and angular (9.6 ± 15.9%) acceleration would be lower. No significant differences were found in coefficient of variation values for linear (Hybrid III: 2.6 ± 2.3%, National Operating Committee on Standards for Athletic Equipment: 2.0 ± 1.4%) or angular (Hybrid III: 4.9 ± 4.0%; National Operating Committee on Standards for Athletic Equipment: 5.2 ± 5.8%) acceleration. These data have application toward development and validation of future helmet evaluation protocols and standards. © IMechE 2015.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Johnson, K L; Chowdhury, S; Lawrimore, W B; Mao, Y; Mehmani, A; Prabhu, R; Rush, G A; Horstemeyer, M F
Constrained topological optimization of a football helmet facemask based on brain response Journal Article
In: Materials and Design, vol. 111, pp. 108–118, 2016.
@article{Johnson2016a,
title = {Constrained topological optimization of a football helmet facemask based on brain response},
author = {Johnson, K L and Chowdhury, S and Lawrimore, W B and Mao, Y and Mehmani, A and Prabhu, R and Rush, G A and Horstemeyer, M F},
doi = {10.1016/j.matdes.2016.08.064},
year = {2016},
date = {2016-01-01},
journal = {Materials and Design},
volume = {111},
pages = {108--118},
abstract = {Surrogate model-based multi-objective design optimization was performed to reduce concussion risk during frontal football helmet impacts. In particular, a topological decomposition of the football helmet facemask was performed to formulate the design problem, and brain injury metrics were exploited as objective functions. A validated finite element model of a helmeted human head was used to recreate facemask impacts. Due to the prohibitive computational expense of the full scale simulations, a surrogate modeling approach was employed. An optimal surrogate model selection framework, called Concurrent Surrogate Model Selection, or COSMOS, was utilized to identify the surrogate models best suited to approximate each objective function. The resulting surrogate models were implemented in the Non-dominated Sorting Genetic Algorithm II (NSGA-II) optimization algorithm. Constraints were implemented to control the solid material fraction in the facemask design space, and binary variables were used to control the placement of the facemask bars. The optimized facemask designs reduced the maximum tensile pressure in the brain by 7.5% and the maximum shear strain by a remarkable 39.5%. This research represents a first-of-its-kind approach to multi-objective design optimization on a football helmet, and demonstrates the possibilities that are achievable in improving human safety by using such a simulation-based design optimization. © 2016 Elsevier Ltd},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Bowman, T G; Breedlove, K M; Breedlove, E L; Dodge, T M; Nauman, E A
Impact attenuation properties of new and used lacrosse helmets Journal Article
In: Journal of Biomechanics, vol. 48, no. 14, pp. 3782–3787, 2015.
@article{Bowman2015,
title = {Impact attenuation properties of new and used lacrosse helmets},
author = {Bowman, T G and Breedlove, K M and Breedlove, E L and Dodge, T M and Nauman, E A},
doi = {10.1016/j.jbiomech.2015.08.026},
year = {2015},
date = {2015-01-01},
journal = {Journal of Biomechanics},
volume = {48},
number = {14},
pages = {3782--3787},
abstract = {The National Operating Committee on Standards for Athletic Equipment (NOCSAE) has developed impact attenuation thresholds that protective helmets worn in sport must meet to be commercially available in an attempt to prevent injury. It remains unknown how normal helmet use in athletic activity alters the force attenuation ability of lacrosse helmets. We tested 3 new and 3 randomly selected used helmets from 2 popular lacrosse models (Cascade Pro7, Cascade CPXR). All used helmets had been worn for 3 collegiate seasons prior to testing and had never been refurbished. Helmets were drop-tested using 3 prescribed impact velocities at 6 locations according to the NOCSAE lacrosse helmet standard, and we compared the Gadd Severity Index (GSI) scores between new and used helmets using a repeated measure ANOVA with location as the repeated variable and data separated by impact velocity. All 12 helmets passed the NOCSAE GSI threshold for all testing conditions; however 1 used helmet shell cracked resulting in a failed test. We found a significant main effect for helmet age at the low (F5},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Whyte, Thomas; Gibson, Tom; Anderson, Robert; Eager, David; Milthorpe, Bruce
Mechanisms of head and neck injuries sustained by helmeted motorcyclists in fatal real-world crashes: Analysis of 47 in-depth cases Journal Article
In: Journal of Neurotrauma, vol. 33, no. 19, pp. 1802–1807, 2016, ISBN: 0897-7151 1557-9042.
Abstract | Links | BibTeX | Tags: 2016, BRAIN damage, Head Injuries, Helmet, mechanisms, Motor Vehicles, motorcyclist, Safety devices, traumatic injury
@article{Whyte2016,
title = {Mechanisms of head and neck injuries sustained by helmeted motorcyclists in fatal real-world crashes: Analysis of 47 in-depth cases},
author = {Whyte, Thomas and Gibson, Tom and Anderson, Robert and Eager, David and Milthorpe, Bruce},
doi = {10.1089/neu.2015.4208},
isbn = {0897-7151
1557-9042},
year = {2016},
date = {2016-01-01},
journal = {Journal of Neurotrauma},
volume = {33},
number = {19},
pages = {1802--1807},
publisher = {Mary Ann Liebert, Inc.},
address = {US},
abstract = {Despite an improved understanding of traumatic head and neck injury mechanisms, the impact tests required by major motorcycle helmet standards have remained unchanged for decades. Development of new test methods must reflect the specific impact loads causing injury in real crashes as well as test criteria appropriate for the observed injury profiles. This study analysed a collection of in-depth crash investigations of fatally injured helmeted riders in the Adelaide metropolitan region between 1983 and 1994 inclusive to review the head and neck injury patterns that resulted from specific types of impact. Inertial brain injury was sustained in 49% of examined cases, most often resulting from facial impacts but also in a large proportion of tangential, run over, and occipital impact cases. Focal brain and brainstem injury was also common (53%) and regularly associated with skull vault (11/12) and skull base fractures (22/31). Prevention of these fractures in impacts outside the area of required protection and in impacts with a straight edge would provide a significant increase in helmeted rider protection. Cervical spinal cord injury was sustained in facial, straight edge, and tangential impacts on the head. Motorcycle helmets are effective for preventing local skull fractures in impacts for which they are designed, whereas other serious injuries such as basilar skull fracture (BSF) and inertial brain injury persist despite helmet protection. Further impact test procedures should be developed for injurious impact types not currently assessed by major helmet standards, in particular facial impacts, and using test criteria based on commonly observed injuries. This study provides the necessary link, from impact load to injury, for guiding impact test development. (PsycINFO Database Record (c) 2016 APA, all rights reserved)},
keywords = {2016, BRAIN damage, Head Injuries, Helmet, mechanisms, Motor Vehicles, motorcyclist, Safety devices, traumatic injury},
pubstate = {published},
tppubtype = {article}
}
Cobb, B R; Zadnik, A M; Rowson, S
Comparative analysis of helmeted impact response of Hybrid III and National Operating Committee on Standards for Athletic Equipment headforms Journal Article
In: Proceedings of the Institution of Mechanical Engineers, Part P: Journal of Sports Engineering and Technology, vol. 230, no. 1, pp. 50–60, 2016.
Abstract | Links | BibTeX | Tags: Acceleration, Accident prevention, Angular acceleration, Biomechanics, Brain Injury, Coefficient of variation values, Comparative analysis, Concussion, Equipment, Evaluation protocol, helmet testing, Linear acceleration, Linear accelerations, Rotational acceleration, Safety devices, Sporting goods, standards
@article{Cobb2016,
title = {Comparative analysis of helmeted impact response of Hybrid III and National Operating Committee on Standards for Athletic Equipment headforms},
author = {Cobb, B R and Zadnik, A M and Rowson, S},
doi = {10.1177/1754337115599133},
year = {2016},
date = {2016-01-01},
journal = {Proceedings of the Institution of Mechanical Engineers, Part P: Journal of Sports Engineering and Technology},
volume = {230},
number = {1},
pages = {50--60},
abstract = {As advanced helmet testing methodologies are developed, the effect headform selection may have on the biomechanical impact response must be considered. This study sought to assess response differences between two of the most commonly used headforms, the Hybrid III and National Operating Committee on Standards for Athletic Equipment headforms, through a series of helmeted impact tests. A total of 180 pendulum impact tests were conducted with three impactor velocities and six impact locations. Test condition-specific significant differences were found between the two headforms for peak linear and angular accelerations ($alpha$ = 0.05), although differences tended to be small. On average, the National Operating Committee on Standards for Athletic Equipment headform experienced higher peak linear (3.7 ± 7.8%) and angular (12.0 ± 21.6%) accelerations, with some of the largest differences associated with impacts to the facemask. Without the facemask impacts, the average differences in linear (1.8 ± 6.0%) and angular (9.6 ± 15.9%) acceleration would be lower. No significant differences were found in coefficient of variation values for linear (Hybrid III: 2.6 ± 2.3%, National Operating Committee on Standards for Athletic Equipment: 2.0 ± 1.4%) or angular (Hybrid III: 4.9 ± 4.0%; National Operating Committee on Standards for Athletic Equipment: 5.2 ± 5.8%) acceleration. These data have application toward development and validation of future helmet evaluation protocols and standards. © IMechE 2015.},
keywords = {Acceleration, Accident prevention, Angular acceleration, Biomechanics, Brain Injury, Coefficient of variation values, Comparative analysis, Concussion, Equipment, Evaluation protocol, helmet testing, Linear acceleration, Linear accelerations, Rotational acceleration, Safety devices, Sporting goods, standards},
pubstate = {published},
tppubtype = {article}
}
Johnson, K L; Chowdhury, S; Lawrimore, W B; Mao, Y; Mehmani, A; Prabhu, R; Rush, G A; Horstemeyer, M F
Constrained topological optimization of a football helmet facemask based on brain response Journal Article
In: Materials and Design, vol. 111, pp. 108–118, 2016.
Abstract | Links | BibTeX | Tags: Accident prevention, ALGORITHMS, brain, Concussion, Constrained optimization, Design, Design optimization, finite element analysis, Finite element method, football helmet, Fuel additives, Genetic algorithms, Multiobjective optimization, Optimization, Safety devices, Shear strain, Sports, Surrogate model, Surrogate modeling, Topology, Traumatic Brain Injuries, traumatic brain injury
@article{Johnson2016a,
title = {Constrained topological optimization of a football helmet facemask based on brain response},
author = {Johnson, K L and Chowdhury, S and Lawrimore, W B and Mao, Y and Mehmani, A and Prabhu, R and Rush, G A and Horstemeyer, M F},
doi = {10.1016/j.matdes.2016.08.064},
year = {2016},
date = {2016-01-01},
journal = {Materials and Design},
volume = {111},
pages = {108--118},
abstract = {Surrogate model-based multi-objective design optimization was performed to reduce concussion risk during frontal football helmet impacts. In particular, a topological decomposition of the football helmet facemask was performed to formulate the design problem, and brain injury metrics were exploited as objective functions. A validated finite element model of a helmeted human head was used to recreate facemask impacts. Due to the prohibitive computational expense of the full scale simulations, a surrogate modeling approach was employed. An optimal surrogate model selection framework, called Concurrent Surrogate Model Selection, or COSMOS, was utilized to identify the surrogate models best suited to approximate each objective function. The resulting surrogate models were implemented in the Non-dominated Sorting Genetic Algorithm II (NSGA-II) optimization algorithm. Constraints were implemented to control the solid material fraction in the facemask design space, and binary variables were used to control the placement of the facemask bars. The optimized facemask designs reduced the maximum tensile pressure in the brain by 7.5% and the maximum shear strain by a remarkable 39.5%. This research represents a first-of-its-kind approach to multi-objective design optimization on a football helmet, and demonstrates the possibilities that are achievable in improving human safety by using such a simulation-based design optimization. © 2016 Elsevier Ltd},
keywords = {Accident prevention, ALGORITHMS, brain, Concussion, Constrained optimization, Design, Design optimization, finite element analysis, Finite element method, football helmet, Fuel additives, Genetic algorithms, Multiobjective optimization, Optimization, Safety devices, Shear strain, Sports, Surrogate model, Surrogate modeling, Topology, Traumatic Brain Injuries, traumatic brain injury},
pubstate = {published},
tppubtype = {article}
}
Bowman, T G; Breedlove, K M; Breedlove, E L; Dodge, T M; Nauman, E A
Impact attenuation properties of new and used lacrosse helmets Journal Article
In: Journal of Biomechanics, vol. 48, no. 14, pp. 3782–3787, 2015.
Abstract | Links | BibTeX | Tags: Accident prevention, Article, Athletic Injuries, attenuation, brain concussion, Cracks, Drop test, Drops, Equipment Design, Gadd Severity Index, head impact, Head Protective Devices, Helmet, Helmet evaluation, human, Humans, Injuries, lacrosse helmet, Materials testing, mechanical stress, priority journal, protective equipment, racquet sport, Racquet Sports, recertification, rigidity, Safety devices, Severity index, Sporting goods, Sports Equipment, standards, stress strain relationship, velocity
@article{Bowman2015,
title = {Impact attenuation properties of new and used lacrosse helmets},
author = {Bowman, T G and Breedlove, K M and Breedlove, E L and Dodge, T M and Nauman, E A},
doi = {10.1016/j.jbiomech.2015.08.026},
year = {2015},
date = {2015-01-01},
journal = {Journal of Biomechanics},
volume = {48},
number = {14},
pages = {3782--3787},
abstract = {The National Operating Committee on Standards for Athletic Equipment (NOCSAE) has developed impact attenuation thresholds that protective helmets worn in sport must meet to be commercially available in an attempt to prevent injury. It remains unknown how normal helmet use in athletic activity alters the force attenuation ability of lacrosse helmets. We tested 3 new and 3 randomly selected used helmets from 2 popular lacrosse models (Cascade Pro7, Cascade CPXR). All used helmets had been worn for 3 collegiate seasons prior to testing and had never been refurbished. Helmets were drop-tested using 3 prescribed impact velocities at 6 locations according to the NOCSAE lacrosse helmet standard, and we compared the Gadd Severity Index (GSI) scores between new and used helmets using a repeated measure ANOVA with location as the repeated variable and data separated by impact velocity. All 12 helmets passed the NOCSAE GSI threshold for all testing conditions; however 1 used helmet shell cracked resulting in a failed test. We found a significant main effect for helmet age at the low (F5},
keywords = {Accident prevention, Article, Athletic Injuries, attenuation, brain concussion, Cracks, Drop test, Drops, Equipment Design, Gadd Severity Index, head impact, Head Protective Devices, Helmet, Helmet evaluation, human, Humans, Injuries, lacrosse helmet, Materials testing, mechanical stress, priority journal, protective equipment, racquet sport, Racquet Sports, recertification, rigidity, Safety devices, Severity index, Sporting goods, Sports Equipment, standards, stress strain relationship, velocity},
pubstate = {published},
tppubtype = {article}
}