cometadata/datacite-titles-descriptions-related-identifiers huggingface dataset:
DOI: 10.6084/m9.figshare.20666063
title: Repositioning forward-leaning vehicle occupants with a pre-pretensioner belt and a startle-based warning in pre-crash scenarios

description: Pre-pretensioner (PPT) seatbelts have been found to be effective in controlling vehicle occupants’ motion response to disturbances in optimally positioned occupants, but it is not clear how the PPT performs when the occupant is initially forward leaning. Previous work demonstrated that an acoustic startling pre-stimulus (ASPS) reduced trunk out-of-position in sled-simulated pre-crash maneuvers. Therefore, the aim of this study was to determine if coupling the PPT with the ASPS could reduce the needed magnitude and rate of belt tension of the PPT to reposition forward leaning occupants to their optimal position within the seatbelt. Sixteen belt-restrained adult human volunteers (8 males and 8 females) restrained by a 3-point seatbelt on a vehicle seat in a forward leaning posture on a sled simulating pre-crash braking (approx. 1 g of maximum acceleration and 0.3 s duration) were exposed to sled perturbations with three belt configurations (low and high force PPT and no PPT), and two warning conditions (ASPS and no-ASPS). Head and trunk positions were extracted from the 3D motion-capture data. Repeated measure ANOVAs were used to understand the effect of sex, PPT, ASPS, and repetition on head and trunk positions. A survival analysis was also performed to understand the probability of the occupants moving rearward in the different conditions. The probability of the head and trunk to move rearward from the initial position was greater with the PPT than without the PPT (p = 0.01) and with the high force level than the low force level (p = 0.01). The interaction effect of ASPS x PPT showed that with no PPT, there was a greater probability for the head to move rearward from the initial position with ASPS than without ASPS (p &lt; 0.03). The trunk shows a similar trend to the head, but the ASPS vs no-ASPS differences were not statistically significant (p = 0.06). No sex differences were found. The PPT, particularly the high level, may be an effective countermeasure on its own to reduce trunk and head out-of-position in forward leaning postures in pre-crash scenarios. The ASPS reduced the occupants’ head forward position when the PPT was not available.
DOI: 10.6084/m9.figshare.20666063.v1
title: Repositioning forward-leaning vehicle occupants with a pre-pretensioner belt and a startle-based warning in pre-crash scenarios

description: Pre-pretensioner (PPT) seatbelts have been found to be effective in controlling vehicle occupants’ motion response to disturbances in optimally positioned occupants, but it is not clear how the PPT performs when the occupant is initially forward leaning. Previous work demonstrated that an acoustic startling pre-stimulus (ASPS) reduced trunk out-of-position in sled-simulated pre-crash maneuvers. Therefore, the aim of this study was to determine if coupling the PPT with the ASPS could reduce the needed magnitude and rate of belt tension of the PPT to reposition forward leaning occupants to their optimal position within the seatbelt. Sixteen belt-restrained adult human volunteers (8 males and 8 females) restrained by a 3-point seatbelt on a vehicle seat in a forward leaning posture on a sled simulating pre-crash braking (approx. 1 g of maximum acceleration and 0.3 s duration) were exposed to sled perturbations with three belt configurations (low and high force PPT and no PPT), and two warning conditions (ASPS and no-ASPS). Head and trunk positions were extracted from the 3D motion-capture data. Repeated measure ANOVAs were used to understand the effect of sex, PPT, ASPS, and repetition on head and trunk positions. A survival analysis was also performed to understand the probability of the occupants moving rearward in the different conditions. The probability of the head and trunk to move rearward from the initial position was greater with the PPT than without the PPT (p = 0.01) and with the high force level than the low force level (p = 0.01). The interaction effect of ASPS x PPT showed that with no PPT, there was a greater probability for the head to move rearward from the initial position with ASPS than without ASPS (p &lt; 0.03). The trunk shows a similar trend to the head, but the ASPS vs no-ASPS differences were not statistically significant (p = 0.06). No sex differences were found. The PPT, particularly the high level, may be an effective countermeasure on its own to reduce trunk and head out-of-position in forward leaning postures in pre-crash scenarios. The ASPS reduced the occupants’ head forward position when the PPT was not available.
DOI: 10.6084/m9.figshare.21593757
title: An investigation of elderly occupant injury risks based on anthropometric changes compared to young counterparts

description: The objective of the study was to investigate the difference between elderly and young occupant injury risks using human body finite element modeling in frontal impacts. Two elderly male occupant models (representative age 70–80 years) were developed using the Global Human Body Consortium (GHBMC) 50th percentile as the baseline model. In the first elderly model (EM-1), material property changes were incorporated, and in the second elderly model (EM-2), material and anthropometric changes were incorporated. Material properties were based on literature. The baseline model was morphed to elderly anthropometry for EM-2. The three models were simulated in a frontal crash vehicle environment at 56 km/h. Responses from the two elderly and baseline models were compared with cadaver experimental data in thoracic, abdominal, and frontal impacts. Correlation and analysis scores were used for correlation with experimental data. The probabilities of head, neck, and thoracic injuries were assessed. The elderly models showed a good correlation with experimental responses. The elderly EM-1 had higher risk of head and brain injuries compared to the elderly EM-2 and baseline GHBMC models. The elderly EM-2 demonstrated higher risk of neck, chest, and abdominal injuries than the elderly EM-1 and baseline models. The study investigated injury risks of two elderly occupants and compared to a young occupant in frontal crashes. The change in the material properties alone (EM-1) suggested that elderly occupants may be vulnerable to a greater risk of head and thoracic injuries, whereas change in both anthropometric and material properties (EM-2) suggested that elderly occupants may be vulnerable to a greater risk of thoracic and neck injuries. The second elderly model results were in better agreement with field injury data from the literature; thus, both anthropometric and material properties should be considered when assessing the injury risks of elderly occupants. The elderly models developed in this study can be used to simulate different impact conditions and determine injury risks for this group of our population.
DOI: 10.6084/m9.figshare.21593757.v1
title: An investigation of elderly occupant injury risks based on anthropometric changes compared to young counterparts

description: The objective of the study was to investigate the difference between elderly and young occupant injury risks using human body finite element modeling in frontal impacts. Two elderly male occupant models (representative age 70–80 years) were developed using the Global Human Body Consortium (GHBMC) 50th percentile as the baseline model. In the first elderly model (EM-1), material property changes were incorporated, and in the second elderly model (EM-2), material and anthropometric changes were incorporated. Material properties were based on literature. The baseline model was morphed to elderly anthropometry for EM-2. The three models were simulated in a frontal crash vehicle environment at 56 km/h. Responses from the two elderly and baseline models were compared with cadaver experimental data in thoracic, abdominal, and frontal impacts. Correlation and analysis scores were used for correlation with experimental data. The probabilities of head, neck, and thoracic injuries were assessed. The elderly models showed a good correlation with experimental responses. The elderly EM-1 had higher risk of head and brain injuries compared to the elderly EM-2 and baseline GHBMC models. The elderly EM-2 demonstrated higher risk of neck, chest, and abdominal injuries than the elderly EM-1 and baseline models. The study investigated injury risks of two elderly occupants and compared to a young occupant in frontal crashes. The change in the material properties alone (EM-1) suggested that elderly occupants may be vulnerable to a greater risk of head and thoracic injuries, whereas change in both anthropometric and material properties (EM-2) suggested that elderly occupants may be vulnerable to a greater risk of thoracic and neck injuries. The second elderly model results were in better agreement with field injury data from the literature; thus, both anthropometric and material properties should be considered when assessing the injury risks of elderly occupants. The elderly models developed in this study can be used to simulate different impact conditions and determine injury risks for this group of our population.
DOI: 10.6084/m9.figshare.20449741
title: Pilot characterization of head kinematics in grassroots dirt track racing

description: The objective of this study was to utilize an instrumented mouthpiece sensor to characterize head kinematics experienced by grassroots dirt track race car drivers. Four dirt track race car drivers (ages 16–19) were instrumented with custom mouthpiece sensors capable of accurately measuring head motion during racing. Sensors were deployed before races and recorded tri-axial linear acceleration and rotational velocity for approximately 10 min at 200 Hz. Film review was performed to identify data associated with racing laps. For each lap, moving average kinematics were computed and subtracted from the head motion signals to obtain ‘adjusted’ head motion accounting for lower frequency variance due to periodic motion around the track. From adjusted data, linear and angular head perturbations (i.e., deviations from moving average) were extracted using a custom algorithm. Data was collected during 400 driver-races. A total of 2438 laps were segmented from mouthpiece recordings. The median (95th percentile) peak linear acceleration, rotational velocity, and rotational acceleration of all laps were 5.33 (8.28) g, 2.89 (4.60) rad/s, and 179 (310) rad/s<sup>2</sup>, respectively. Angular perturbations occurred most frequently about the anterior-posterior axis (median lap frequency = 6.39 Hz); whereas linear perturbations occurred most frequently in the inferior-superior direction (7.96 Hz). Nine crash events were recorded by the mouthpiece sensors. The median (95<sup>th</sup> percentile) peak head kinematics of these events were 13.4 (36.6) g, 9.67 (21.9) rad/s, and 630 (1330) rad/s<sup>2</sup>. Mouthpiece sensors can be used to measure head kinematics during active racing. Laps, head perturbations, and crashes may be useful units of observation to describe typical head kinematic exposure experienced by drivers while racing. Subsequent research is needed to understand the associations between repetitive racing exposure and neurological function. Higher magnitude events (i.e., crashes) are not uncommon and may result in concussion or more severe injury. Results represent novel characterizations of head kinematic exposure experienced in a dirt track racing environment. This information may inform evidence-based strategies (e.g., vehicle/seat design) to improve driver safety.
DOI: 10.6084/m9.figshare.20449741.v1
title: Pilot characterization of head kinematics in grassroots dirt track racing

description: The objective of this study was to utilize an instrumented mouthpiece sensor to characterize head kinematics experienced by grassroots dirt track race car drivers. Four dirt track race car drivers (ages 16–19) were instrumented with custom mouthpiece sensors capable of accurately measuring head motion during racing. Sensors were deployed before races and recorded tri-axial linear acceleration and rotational velocity for approximately 10 min at 200 Hz. Film review was performed to identify data associated with racing laps. For each lap, moving average kinematics were computed and subtracted from the head motion signals to obtain ‘adjusted’ head motion accounting for lower frequency variance due to periodic motion around the track. From adjusted data, linear and angular head perturbations (i.e., deviations from moving average) were extracted using a custom algorithm. Data was collected during 400 driver-races. A total of 2438 laps were segmented from mouthpiece recordings. The median (95th percentile) peak linear acceleration, rotational velocity, and rotational acceleration of all laps were 5.33 (8.28) g, 2.89 (4.60) rad/s, and 179 (310) rad/s<sup>2</sup>, respectively. Angular perturbations occurred most frequently about the anterior-posterior axis (median lap frequency = 6.39 Hz); whereas linear perturbations occurred most frequently in the inferior-superior direction (7.96 Hz). Nine crash events were recorded by the mouthpiece sensors. The median (95<sup>th</sup> percentile) peak head kinematics of these events were 13.4 (36.6) g, 9.67 (21.9) rad/s, and 630 (1330) rad/s<sup>2</sup>. Mouthpiece sensors can be used to measure head kinematics during active racing. Laps, head perturbations, and crashes may be useful units of observation to describe typical head kinematic exposure experienced by drivers while racing. Subsequent research is needed to understand the associations between repetitive racing exposure and neurological function. Higher magnitude events (i.e., crashes) are not uncommon and may result in concussion or more severe injury. Results represent novel characterizations of head kinematic exposure experienced in a dirt track racing environment. This information may inform evidence-based strategies (e.g., vehicle/seat design) to improve driver safety.
DOI: 10.6084/m9.figshare.21388256
title: Identifying community-level disparities in access to driver education and training: Toward a definition of driver training deserts

description: Obtaining a license may be challenging for teens due to access to driving instruction; in some states, behind-the-wheel (BTW) instruction is required to secure a license before age 18. We investigate spatial accessibility to BTW centers, and how this geographic distribution intersects with metrics of social disparity at the metropolitan level, toward identifying Driver Training Deserts (DTDs): geographic areas of disconnection to driver training. For the Columbus OH region, we collect socioeconomic variables at the Census tract unit of analysis and geocoded locations of public and private BTW training centers and estimate travel time to the nearest BTW training center. We define travel time as either the mean or the maximum travel time to BTW centers across all 1 km × 1 km grid cells within a Census tract. We employ spatial statistical approaches, including homogeneous/inhomogeneous K functions, to determine whether BTW training centers are clustered. Next, we define DTDs as Census tracts with a poverty rate and travel time to BTW centers larger than the 75th percentile values across the region. BTW training centers are spatially clustered across the region; the magnitude of this clustering is so great that BTW centers exhibit statistically significant patterns of clustering, even when considering the underlying spatial distribution of socio-economic characteristics. We find that 11–27 Census tracts are identified as DTDs depending on the definition of travel time. DTDs contain a disproportionate percent of the high poverty population (8.7–23.5%) and, depending on the definition of travel time, a disproportionately large African American population. Methodologically, defining DTDs necessitates a fine-grained spatial approach as suburban and rural Census tracts tend to be large and thus can be poorly represented by travel times averaged over the Census tract. Defining DTDs as a measure of individual-specific variables – income and impedance – allows DTDs to be addressed with policy interventions. The findings motivate future research correlating DTDs with licensure rates, enrollment in driver training, and safe driving outcomes to understand if DTDs can help explain health equity outcomes related to young driver safety.
DOI: 10.6084/m9.figshare.21388256.v1
title: Identifying community-level disparities in access to driver education and training: Toward a definition of driver training deserts

description: Obtaining a license may be challenging for teens due to access to driving instruction; in some states, behind-the-wheel (BTW) instruction is required to secure a license before age 18. We investigate spatial accessibility to BTW centers, and how this geographic distribution intersects with metrics of social disparity at the metropolitan level, toward identifying Driver Training Deserts (DTDs): geographic areas of disconnection to driver training. For the Columbus OH region, we collect socioeconomic variables at the Census tract unit of analysis and geocoded locations of public and private BTW training centers and estimate travel time to the nearest BTW training center. We define travel time as either the mean or the maximum travel time to BTW centers across all 1 km × 1 km grid cells within a Census tract. We employ spatial statistical approaches, including homogeneous/inhomogeneous K functions, to determine whether BTW training centers are clustered. Next, we define DTDs as Census tracts with a poverty rate and travel time to BTW centers larger than the 75th percentile values across the region. BTW training centers are spatially clustered across the region; the magnitude of this clustering is so great that BTW centers exhibit statistically significant patterns of clustering, even when considering the underlying spatial distribution of socio-economic characteristics. We find that 11–27 Census tracts are identified as DTDs depending on the definition of travel time. DTDs contain a disproportionate percent of the high poverty population (8.7–23.5%) and, depending on the definition of travel time, a disproportionately large African American population. Methodologically, defining DTDs necessitates a fine-grained spatial approach as suburban and rural Census tracts tend to be large and thus can be poorly represented by travel times averaged over the Census tract. Defining DTDs as a measure of individual-specific variables – income and impedance – allows DTDs to be addressed with policy interventions. The findings motivate future research correlating DTDs with licensure rates, enrollment in driver training, and safe driving outcomes to understand if DTDs can help explain health equity outcomes related to young driver safety.
DOI: 10.6084/m9.figshare.20051765
title: Influence of cannabis use history on the impact of acute cannabis smoking on simulated driving performance during a distraction task

description: <b>Objective:</b> This research explores the driving performance of people who use cannabis daily or occasionally during distraction tasks performed following acute cannabis use. <b>Methods:</b> Healthy adults aged 25 to 45 years with different cannabis usage histories were recruited to participate in a within-subjects controlled experiment using a car-based driving simulator. Participants were classified as having daily use (n = 31), occasional use (1 or 2 times per week; n = 24), or no-use (n = 30). Participants completed a practice drive followed by four 5–10 minute driving scenarios during the baseline period. Participants then smoked self-procured cannabis flower ad libitum for up to 15 minutes. Thirty minutes later, they completed four additional 5–10 minute scenarios. Scenarios were paired according to difficulty and randomized across the baseline and post-use periods. Each scenario contained between 0 and 3 repetitions of a distraction task where the participant was prompted by an audio message to select an app from a 4 × 5 grid displayed on a mounted tablet, a step that would require briefly looking away from the roadway. Measures of driving performance (lane departures, standard deviation of lateral position) were assessed during the five-second period following the audio trigger and analyzed using generalized linear mixed models. <b>Results:</b> Those with a pattern of occasional use were significantly more likely to experience a lane departure during distraction periods after acute cannabis use relative to baseline (OR = 3.71, <i>p</i> = 0.04, CI = 1.04, 13.17), while those with daily use did not exhibit a similar increase (OR = 1.56, <i>p</i> = 0.43, CI = 0.52, 4.64). Changes in departure risk were significantly greater for the occasional use group compared to no-use (<i>p</i> = 0.02), but not for the daily use group compared to no-use (<i>p</i> = 0.18). However, following acute use, those who use daily exhibited decreases in speed relative to baseline in comparison to the changes observed in the no-use group (<i>p</i> = 0.02), while differences between occasional and no-use did not reach statistical significance (<i>p</i> = 0.052). Differences in standard deviation of lateral position were not statistically significant, likely due to the short duration of tasks. <b>Conclusions:</b> These results find the largest potential safety concerns associated with a pattern of occasional use, who displayed an increase in lane departures after acute cannabis smoking. Those in the daily use group decreased their speed, which may be interpreted as compensation for drug effects. Further research is needed to understand the effects during longer and more complex secondary tasks.