Human Response to Dynamic Rollover Conditions

To date, human responses in motor vehicle rollover accidents have been studied through the use of Hybrid III dummies in dolly vehicle rollover tests, quasi-static spit tests where the vehicle and occupant are rotated slowly about the rotation axis of the spit fixture, computer simulations and vehicle drop tests. To demonstrate human responses to dynamic rollover conditions more accurately we designed and built a fixture to accommodate a passenger compartment in a hoop structure that rotates as it translates. The rotational axis of the hoop structure is offset from the rotational axis of the passenger compartment to replicate vehicle center of gravity motion seen in dolly rollover tests. Testing showed the difference in restraint behavior depending upon whether the occupant was seated on the near (initially leading) or far side. It demonstrated that human and Hybrid III dummy neck response is very different. The human test subject received no injuries from diving into the roof of the passenger compartment even though this is the predicted injury mechanism reported in several technical papers.

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The Sun as a Magnetic Star

International Astronomical Union Colloquium ◽

10.1017/s0252921100080775 ◽

1976 ◽

Vol 32 ◽

pp. 457-463

Author(s):

John M. Wilcox ◽

Leif Svalgaard

Keyword(s):

Recent Work ◽

Rotation Axis ◽

Polar Field ◽

Magnetic Star ◽

Rotational Axis ◽

Field Variation ◽

The Sun ◽

Arbitrary Angle ◽

Solar Magnetism ◽

Oblique Rotator

SummaryThe sun as a magnetic star is described on the basis of recent work on solar magnetism. Observations at an arbitrary angle to the rotation axis would show a 22-year polar field variation and a 25-day equatorial sector variation. The sector variation would be similar to an oblique rotator with an angle of 90° between the magnetic and rotational axis.

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An Investigation of Hybrid III and Living Human Drop Tests

Critical Reviews in Biomedical Engineering ◽

10.1615/critrevbiomedeng.v28.i12.380 ◽

2000 ◽

Vol 28 (1-2) ◽

pp. 219-223 ◽

Cited By ~ 4

Author(s):

Keith Friedman ◽

Fiona Gaston ◽

Jack Bish ◽

Donald Friedman ◽

Anthony Sances, Jr.

Keyword(s):

Hybrid Iii ◽

Drop Tests

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341 Acute effects of seltorexant, a selective orexin-2 antagonist (JNJ- 42847922), on driving after bedtime administration

SLEEP ◽

10.1093/sleep/zsab072.340 ◽

2021 ◽

Vol 44 (Supplement_2) ◽

pp. A136-A136

Author(s):

S Brooks ◽

R G J A Zuiker ◽

G E Jacobs ◽

I Kezic ◽

A Savitz ◽

...

Keyword(s):

Postural Stability ◽

Driving Simulator ◽

Motor Vehicle ◽

Subjective Effects ◽

Driving Ability ◽

Post Dose ◽

Double Blind ◽

Increased Risk ◽

Subjective Sleepiness ◽

The Difference

Abstract Introduction Seltorexant (JNJ-42847922), a potent and selective antagonist of the human orexin-2 receptor, is being developed for the treatment of major depressive disorder. Seltorexant also has sleep-promoting properties. Investigating the effects of sleep-promoting medications on driving is important because some of these agents (e.g. GABAA receptor agonists) may be associated with increased risk of motor vehicle accidents. We evaluated the effect of seltorexant on driving after forced awakening at night, using a validated driving simulator. Methods This double-blind, placebo and active-controlled, randomized, 3-way cross-over study was conducted in 18 male and 18 female healthy subjects. All subjects received seltorexant 40 mg, zolpidem 10 mg, or placebo 15 minutes before bedtime. Eighteen subjects were awakened at 2- and 6-hours post-dose, and the other 18 at 4- and 8-hours post-dose. At those timepoints, pharmacokinetics, objective (standard deviation of the lateral position [SDLP]) and subjective effects (using Perceived Driving Quality and Effort Scales) on driving ability, postural stability and subjective sleepiness were assessed. Results For seltorexant, the SDLP difference from placebo (95% confidence interval) at 2-, 4-, 6- and 8-hours post-dose was 3.9 cm (1.26, 6.60), 0.9 cm (-1.08, 2.92), 1.1 cm (-0.42, 2.63), and 0.6 cm (-2.75, 1.55), respectively vs. 9.6 cm (6.97, 12.38), 6.6 cm (3.53, 9.60), 4.7 cm (1.46, 7.85), and 1.3cm (-1.16, 3.80), respectively for zolpidem. The difference from placebo was significant at 2-hours after taking seltorexant, while the difference from placebo was significant at 2, 4 and 6-hours after zolpidem. Subjective driving quality was decreased for both drugs at all time points and driving effort was increased up to 4-hours post-dose for both medications. Subjective sleepiness showed a significant increase compared to placebo 2- and 4-hours after administration of either drug. Postural stability was decreased up to 2-hours after administration of seltorexant, and up to 4-hours after administration of zolpidem. Conclusion Compared to zolpidem, objective effects on driving performance were more transient after seltorexant administration and largely normalized by 4–6 hours post-dose. Support (if any) This work was sponsored by Janssen R&D.

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Analysis and prediction of polar motion using MSSA method

Earth Planets and Space ◽

10.1186/s40623-021-01477-2 ◽

2021 ◽

Vol 73 (1) ◽

Author(s):

Xin Jin ◽

Xin Liu ◽

Jinyun Guo ◽

Yi Shen

Keyword(s):

Polar Motion ◽

Rotation Axis ◽

Moving Average ◽

Singular Spectrum Analysis ◽

Autoregressive Moving Average ◽

Rotational Axis ◽

Autoregressive Moving Average Model ◽

System Service ◽

Moving Average Model ◽

Polar Motion Prediction

AbstractPolar motion is the movement of the Earth's rotational axis relative to its crust, reflecting the influence of the material exchange and mass redistribution of each layer of the Earth on the Earth's rotation axis. To better analyze the temporally varying characteristics of polar motion, multi-channel singular spectrum analysis (MSSA) was used to analyze the EOP 14 C04 series released by the International Earth Rotation and Reference System Service (IERS) from 1962 to 2020, and the amplitude of the Chandler wobbles were found to fluctuate between 20 and 200 mas and decrease significantly over the last 20 years. The amplitude of annual oscillation fluctuated between 60 and 120 mas, and the long-term trend was 3.72 mas/year, moving towards N56.79 °W. To improve prediction of polar motion, the MSSA method combining linear model and autoregressive moving average model was used to predict polar motion with ahead 1 year, repeatedly. Comparing to predictions of IERS Bulletin A, the results show that the proposed method can effectively predict polar motion, and the improvement rates of polar motion prediction for 365 days into the future were approximately 50% on average.

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Repeatable Dynamic Rollover Roof Test Fixture

Advances in Bioengineering ◽

10.1115/imece2003-43076 ◽

2003 ◽

Cited By ~ 3

Author(s):

Donald Friedman ◽

Acen Jordan ◽

Carl Nash ◽

Jack Bish ◽

Terence Honikman ◽

...

Keyword(s):

Longitudinal Axis ◽

Rolling Motion ◽

Passenger Compartment ◽

Test Device ◽

Test Fixture ◽

Complete Vehicle ◽

Entire Vehicle ◽

Roll Rate ◽

Drop Tests ◽

The Impact

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

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

Journal of Biomechanical Engineering ◽

10.1115/1.4037401 ◽

2017 ◽

Vol 139 (10) ◽

Author(s):

Daniel Aggromito ◽

Mark Jaffrey ◽

Allen Chhor ◽

Bernard Chen ◽

Wenyi Yan

Keyword(s):

Lumbar Spine ◽

Federal Aviation Administration ◽

Relative Displacement ◽

Drop Tower ◽

Test Device ◽

Hybrid Iii ◽

Drop Tests ◽

Occupant Injury ◽

Maximum Relative Displacement ◽

The Impact

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

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Isotypic one-dimensional coordination polymers:catena-poly[[dichloridocadmium]-μ-5,6-bis(pyridin-2-yl)pyrazine-2,3-dicarboxylato-κ2N5:N6] andcatena-poly[[dichloridomercury(II)]-μ-5,6-bis(pyridin-2-yl)pyrazine-2,3-dicarboxylato-κ2N5:N6]

Acta Crystallographica Section E Crystallographic Communications ◽

10.1107/s2056989016012093 ◽

2016 ◽

Vol 72 (8) ◽

pp. 1214-1218 ◽

Cited By ~ 2

Author(s):

Montserrat Alfonso ◽

Helen Stoeckli-Evans

Keyword(s):

Hydrogen Bonds ◽

Metal Ions ◽

Coordination Polymers ◽

Rotation Axis ◽

Dimethyl Ester ◽

Polymer Chains ◽

Coordination Geometry ◽

One Dimensional ◽

The Difference ◽

Title One

The isotypic title one-dimensional coordination polymers, [CdCl2(C18H14N4O4)]n, (I), and [HgCl2(C18H14N4O4)]n, (II), are, respectively, the cadmium(II) and mercury(II) complexes of the dimethyl ester of 5,6-bis(pyridin-2-yl)pyrazine-2,3-dicarboxylic acid. In both compounds, the metal ions are located on a twofold rotation axis and a second such axis bisects the Car—Carbonds of the pyrazine ring. The metal ions are bridged by binding to the N atoms of the two pyridine rings and have anMN2Cl2bisphenoidal coordination geometry. The metal–Npyrazinedistances are much longer than the metal–Npyridinedistances; the difference is 0.389 (2) Å for the Cd—N bonds but only 0.286 (5) Å for the Hg—N bond lengths. In the crystals of both compounds, the polymer chains are linkedviapairs of C—H...Cl hydrogen bonds, forming corrugated slabs parallel to theacplane.

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The Period of Organization of the International Latitude Service: 1889–1899

International Astronomical Union Colloquium ◽

10.1017/s0252921100061261 ◽

2000 ◽

Vol 178 ◽

pp. 121-138

Author(s):

E. Proverbio

Keyword(s):

Principal Axis ◽

Rotation Axis ◽

Systematic Errors ◽

Rotational Axis ◽

The Earth ◽

Secular Variations ◽

Relative Motions

Around 1880, and for some time after that, the possibility of revealing a variation in latitude as a consequence of a separation of the instantaneous rotation axis from the Earth’s axis of inertia gave rise to much perplexity due to the complexity of the problem and the existence of non-negligible and hard-to-find systematic errors in observations of a personal and instrumental nature. These errors also depended on effects of refraction and imprecise knowledge of star declinations.To this must be added the fact that the very idea that the rotational axis and the axis of inertia were distinct and in relative motions raised difficult problems of a physical and theoretical nature. At that time the idea of the Earth’s rigidity was still generally accepted and, even admitting the hypothesis of an Earth endowed with sufficient elasticity and plasticity, the theory of which had been partly examined by G.H. Darwin, it was then almost impossible, just as it still is today, to create a model of the movements of mass inside the Earth which could offer an explanation of possible aperiodic and secular variations. In reality, more than on the existence of periodic variations, the attention and interest of geodesists and astronomers was in those years focused on the problem of the existence or non-existence of secular variations in the Earth’s principal axis.

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Effect of Head Restraint Position and Neck Injury Criteria in Rear Impact

Advances in Bioengineering ◽

10.1115/imece2002-32642 ◽

2002 ◽

Author(s):

John DeRosia ◽

Narayan Yoganandan ◽

Frank A. Pintar

Keyword(s):

Motor Vehicle ◽

Vehicle Safety ◽

Bending Moments ◽

Safety Standards ◽

Acceleration Pulse ◽

Head Restraint ◽

Rear Impact ◽

Injury Criteria ◽

Hybrid Iii ◽

Impact Acceleration

The objective of this study was to determine the forces and bending moments at the top of the Hybrid III dummy neck secondary to rear impact acceleration and evaluate the various proposed injury criteria. Rear impact sled tests were conducted by applying the Federal Motor Vehicle Safety Standards FMVSS 202 acceleration pulse. Differing positions of the head restraint in terms of height (750 and 800 mm) and backset (zero, 50, and 100 mm) were used to determine the axial and shear forces, bending moments, and injury criteria (NIC, Nij, and Nkm). The time sequence of attainment of these parameters was determined along with peak values.

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