Wu, L C; Nangia, V; Bui, K; Hammoor, B; Kurt, M; Hernandez, F; Kuo, C; Camarillo, D B
In Vivo Evaluation of Wearable Head Impact Sensors Journal Article
In: Annals of Biomedical Engineering, vol. 44, no. 4, pp. 1234–1245, 2016.
Abstract | BibTeX | Tags: *Head Movements/ph [Physiology], *Models, *Soccer/ph [Physiology], *Telemetry/is [Instrumentation], adult, Biological, Biomechanical Phenomena, Craniocerebral Trauma, Humans, Male, MOUTH protectors, Skin, Soccer/in [Injuries], VIDEO recording
@article{Wu2016,
title = {In Vivo Evaluation of Wearable Head Impact Sensors},
author = {Wu, L C and Nangia, V and Bui, K and Hammoor, B and Kurt, M and Hernandez, F and Kuo, C and Camarillo, D B},
year = {2016},
date = {2016-01-01},
journal = {Annals of Biomedical Engineering},
volume = {44},
number = {4},
pages = {1234--1245},
abstract = {Inertial sensors are commonly used to measure human head motion. Some sensors have been tested with dummy or cadaver experiments with mixed results, and methods to evaluate sensors in vivo are lacking. Here we present an in vivo method using high speed video to test teeth-mounted (mouthguard), soft tissue-mounted (skin patch), and headgear-mounted (skull cap) sensors during 6-13 g sagittal soccer head impacts. Sensor coupling to the skull was quantified by displacement from an ear-canal reference. Mouthguard displacements were within video measurement error (\<1 mm), while the skin patch and skull cap displaced up to 4 and 13 mm from the ear-canal reference, respectively. We used the mouthguard, which had the least displacement from skull, as the reference to assess 6-degree-of-freedom skin patch and skull cap measurements. Linear and rotational acceleration magnitudes were over-predicted by both the skin patch (with 120% NRMS error for a(mag), 290% for alpha(mag)) and the skull cap (320% NRMS error for a(mag), 500% for alpha(mag)). Such over-predictions were largely due to out-of-plane motion. To model sensor error, we found that in-plane skin patch linear acceleration in the anterior-posterior direction could be modeled by an underdamped viscoelastic system. In summary, the mouthguard showed tighter skull coupling than the other sensor mounting approaches. Furthermore, the in vivo methods presented are valuable for investigating skull acceleration sensor technologies.},
keywords = {*Head Movements/ph [Physiology], *Models, *Soccer/ph [Physiology], *Telemetry/is [Instrumentation], adult, Biological, Biomechanical Phenomena, Craniocerebral Trauma, Humans, Male, MOUTH protectors, Skin, Soccer/in [Injuries], VIDEO recording},
pubstate = {published},
tppubtype = {article}
}
Jadischke, R; Viano, D C; Dau, N; King, A I; McCarthy, J
On the accuracy of the Head Impact Telemetry (HIT) System used in football helmets Journal Article
In: Journal of Biomechanics, vol. 46, no. 13, pp. 2310–2315, 2013.
Abstract | BibTeX | Tags: *Head Protective Devices/st [Standards], *Materials Testing, *Sports Equipment/st [Standards], *Telemetry/is [Instrumentation], Adolescent, adult, Equipment Design, football, Humans, Male, Pressure, Young Adult
@article{Jadischke2013,
title = {On the accuracy of the Head Impact Telemetry (HIT) System used in football helmets},
author = {Jadischke, R and Viano, D C and Dau, N and King, A I and McCarthy, J},
year = {2013},
date = {2013-01-01},
journal = {Journal of Biomechanics},
volume = {46},
number = {13},
pages = {2310--2315},
abstract = {On-field measurement of head impacts has relied on the Head Impact Telemetry (HIT) System, which uses helmet mounted accelerometers to determine linear and angular head accelerations. HIT is used in youth and collegiate football to assess the frequency and severity of helmet impacts. This paper evaluates the accuracy of HIT for individual head impacts. Most HIT validations used a medium helmet on a Hybrid III head. However, the appropriate helmet is large based on the Hybrid III head circumference (58 cm) and manufacturer's fitting instructions. An instrumented skull cap was used to measure the pressure between the head of football players (n=63) and their helmet. The average pressure with a large helmet on the Hybrid III was comparable to the average pressure from helmets used by players. A medium helmet on the Hybrid III produced average pressures greater than the 99th percentile volunteer pressure level. Linear impactor tests were conducted using a large and medium helmet on the Hybrid III. Testing was conducted by two independent laboratories. HIT data were compared to data from the Hybrid III equipped with a 3-2-2-2 accelerometer array. The absolute and root mean square error (RMSE) for HIT were computed for each impact (n=90). Fifty-five percent (n=49) had an absolute error greater than 15% while the RMSE was 59.1% for peak linear acceleration. Copyright © 2013 Elsevier Ltd. All rights reserved.},
keywords = {*Head Protective Devices/st [Standards], *Materials Testing, *Sports Equipment/st [Standards], *Telemetry/is [Instrumentation], Adolescent, adult, Equipment Design, football, Humans, Male, Pressure, Young Adult},
pubstate = {published},
tppubtype = {article}
}
Wu, L C; Nangia, V; Bui, K; Hammoor, B; Kurt, M; Hernandez, F; Kuo, C; Camarillo, D B
In Vivo Evaluation of Wearable Head Impact Sensors Journal Article
In: Annals of Biomedical Engineering, vol. 44, no. 4, pp. 1234–1245, 2016.
@article{Wu2016,
title = {In Vivo Evaluation of Wearable Head Impact Sensors},
author = {Wu, L C and Nangia, V and Bui, K and Hammoor, B and Kurt, M and Hernandez, F and Kuo, C and Camarillo, D B},
year = {2016},
date = {2016-01-01},
journal = {Annals of Biomedical Engineering},
volume = {44},
number = {4},
pages = {1234--1245},
abstract = {Inertial sensors are commonly used to measure human head motion. Some sensors have been tested with dummy or cadaver experiments with mixed results, and methods to evaluate sensors in vivo are lacking. Here we present an in vivo method using high speed video to test teeth-mounted (mouthguard), soft tissue-mounted (skin patch), and headgear-mounted (skull cap) sensors during 6-13 g sagittal soccer head impacts. Sensor coupling to the skull was quantified by displacement from an ear-canal reference. Mouthguard displacements were within video measurement error (\<1 mm), while the skin patch and skull cap displaced up to 4 and 13 mm from the ear-canal reference, respectively. We used the mouthguard, which had the least displacement from skull, as the reference to assess 6-degree-of-freedom skin patch and skull cap measurements. Linear and rotational acceleration magnitudes were over-predicted by both the skin patch (with 120% NRMS error for a(mag), 290% for alpha(mag)) and the skull cap (320% NRMS error for a(mag), 500% for alpha(mag)). Such over-predictions were largely due to out-of-plane motion. To model sensor error, we found that in-plane skin patch linear acceleration in the anterior-posterior direction could be modeled by an underdamped viscoelastic system. In summary, the mouthguard showed tighter skull coupling than the other sensor mounting approaches. Furthermore, the in vivo methods presented are valuable for investigating skull acceleration sensor technologies.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Jadischke, R; Viano, D C; Dau, N; King, A I; McCarthy, J
On the accuracy of the Head Impact Telemetry (HIT) System used in football helmets Journal Article
In: Journal of Biomechanics, vol. 46, no. 13, pp. 2310–2315, 2013.
@article{Jadischke2013,
title = {On the accuracy of the Head Impact Telemetry (HIT) System used in football helmets},
author = {Jadischke, R and Viano, D C and Dau, N and King, A I and McCarthy, J},
year = {2013},
date = {2013-01-01},
journal = {Journal of Biomechanics},
volume = {46},
number = {13},
pages = {2310--2315},
abstract = {On-field measurement of head impacts has relied on the Head Impact Telemetry (HIT) System, which uses helmet mounted accelerometers to determine linear and angular head accelerations. HIT is used in youth and collegiate football to assess the frequency and severity of helmet impacts. This paper evaluates the accuracy of HIT for individual head impacts. Most HIT validations used a medium helmet on a Hybrid III head. However, the appropriate helmet is large based on the Hybrid III head circumference (58 cm) and manufacturer's fitting instructions. An instrumented skull cap was used to measure the pressure between the head of football players (n=63) and their helmet. The average pressure with a large helmet on the Hybrid III was comparable to the average pressure from helmets used by players. A medium helmet on the Hybrid III produced average pressures greater than the 99th percentile volunteer pressure level. Linear impactor tests were conducted using a large and medium helmet on the Hybrid III. Testing was conducted by two independent laboratories. HIT data were compared to data from the Hybrid III equipped with a 3-2-2-2 accelerometer array. The absolute and root mean square error (RMSE) for HIT were computed for each impact (n=90). Fifty-five percent (n=49) had an absolute error greater than 15% while the RMSE was 59.1% for peak linear acceleration. Copyright © 2013 Elsevier Ltd. All rights reserved.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Wu, L C; Nangia, V; Bui, K; Hammoor, B; Kurt, M; Hernandez, F; Kuo, C; Camarillo, D B
In Vivo Evaluation of Wearable Head Impact Sensors Journal Article
In: Annals of Biomedical Engineering, vol. 44, no. 4, pp. 1234–1245, 2016.
Abstract | BibTeX | Tags: *Head Movements/ph [Physiology], *Models, *Soccer/ph [Physiology], *Telemetry/is [Instrumentation], adult, Biological, Biomechanical Phenomena, Craniocerebral Trauma, Humans, Male, MOUTH protectors, Skin, Soccer/in [Injuries], VIDEO recording
@article{Wu2016,
title = {In Vivo Evaluation of Wearable Head Impact Sensors},
author = {Wu, L C and Nangia, V and Bui, K and Hammoor, B and Kurt, M and Hernandez, F and Kuo, C and Camarillo, D B},
year = {2016},
date = {2016-01-01},
journal = {Annals of Biomedical Engineering},
volume = {44},
number = {4},
pages = {1234--1245},
abstract = {Inertial sensors are commonly used to measure human head motion. Some sensors have been tested with dummy or cadaver experiments with mixed results, and methods to evaluate sensors in vivo are lacking. Here we present an in vivo method using high speed video to test teeth-mounted (mouthguard), soft tissue-mounted (skin patch), and headgear-mounted (skull cap) sensors during 6-13 g sagittal soccer head impacts. Sensor coupling to the skull was quantified by displacement from an ear-canal reference. Mouthguard displacements were within video measurement error (\<1 mm), while the skin patch and skull cap displaced up to 4 and 13 mm from the ear-canal reference, respectively. We used the mouthguard, which had the least displacement from skull, as the reference to assess 6-degree-of-freedom skin patch and skull cap measurements. Linear and rotational acceleration magnitudes were over-predicted by both the skin patch (with 120% NRMS error for a(mag), 290% for alpha(mag)) and the skull cap (320% NRMS error for a(mag), 500% for alpha(mag)). Such over-predictions were largely due to out-of-plane motion. To model sensor error, we found that in-plane skin patch linear acceleration in the anterior-posterior direction could be modeled by an underdamped viscoelastic system. In summary, the mouthguard showed tighter skull coupling than the other sensor mounting approaches. Furthermore, the in vivo methods presented are valuable for investigating skull acceleration sensor technologies.},
keywords = {*Head Movements/ph [Physiology], *Models, *Soccer/ph [Physiology], *Telemetry/is [Instrumentation], adult, Biological, Biomechanical Phenomena, Craniocerebral Trauma, Humans, Male, MOUTH protectors, Skin, Soccer/in [Injuries], VIDEO recording},
pubstate = {published},
tppubtype = {article}
}
Jadischke, R; Viano, D C; Dau, N; King, A I; McCarthy, J
On the accuracy of the Head Impact Telemetry (HIT) System used in football helmets Journal Article
In: Journal of Biomechanics, vol. 46, no. 13, pp. 2310–2315, 2013.
Abstract | BibTeX | Tags: *Head Protective Devices/st [Standards], *Materials Testing, *Sports Equipment/st [Standards], *Telemetry/is [Instrumentation], Adolescent, adult, Equipment Design, football, Humans, Male, Pressure, Young Adult
@article{Jadischke2013,
title = {On the accuracy of the Head Impact Telemetry (HIT) System used in football helmets},
author = {Jadischke, R and Viano, D C and Dau, N and King, A I and McCarthy, J},
year = {2013},
date = {2013-01-01},
journal = {Journal of Biomechanics},
volume = {46},
number = {13},
pages = {2310--2315},
abstract = {On-field measurement of head impacts has relied on the Head Impact Telemetry (HIT) System, which uses helmet mounted accelerometers to determine linear and angular head accelerations. HIT is used in youth and collegiate football to assess the frequency and severity of helmet impacts. This paper evaluates the accuracy of HIT for individual head impacts. Most HIT validations used a medium helmet on a Hybrid III head. However, the appropriate helmet is large based on the Hybrid III head circumference (58 cm) and manufacturer's fitting instructions. An instrumented skull cap was used to measure the pressure between the head of football players (n=63) and their helmet. The average pressure with a large helmet on the Hybrid III was comparable to the average pressure from helmets used by players. A medium helmet on the Hybrid III produced average pressures greater than the 99th percentile volunteer pressure level. Linear impactor tests were conducted using a large and medium helmet on the Hybrid III. Testing was conducted by two independent laboratories. HIT data were compared to data from the Hybrid III equipped with a 3-2-2-2 accelerometer array. The absolute and root mean square error (RMSE) for HIT were computed for each impact (n=90). Fifty-five percent (n=49) had an absolute error greater than 15% while the RMSE was 59.1% for peak linear acceleration. Copyright © 2013 Elsevier Ltd. All rights reserved.},
keywords = {*Head Protective Devices/st [Standards], *Materials Testing, *Sports Equipment/st [Standards], *Telemetry/is [Instrumentation], Adolescent, adult, Equipment Design, football, Humans, Male, Pressure, Young Adult},
pubstate = {published},
tppubtype = {article}
}