Common Errors in Determining Impact Speed and Occupant Injury Propensity in Low Speed Rear-End Collisions

Go-karts are a common amusement park feature enjoyed by people of all ages. While intended for racing, contact between go-karts does occur. To investigate and quantify the accelerations and forces which result from contact, 44 low-speed impacts were conducted between a stationary (target) and a moving (bullet) go-kart. The occupant of the bullet go-kart was one of two human volunteers. The occupant of the target go-kart was a Hybrid III 50th percentile male anthropomorphic test device (ATD). Impact configurations consisted of rear-end impacts, frontal impacts, side impacts, and oblique impacts. Results demonstrated high repeatability for the vehicle performance and occupant response. Go-kart accelerations and speed changes increased with increased impact speed. Impact duration and restitution generally decreased with increased impact speed. All ATD acceleration, force, and moment values increased with increased impact speed. Common injury metrics such as the head injury criterion (HIC), Nij, and Nkm were calculated and were found to be below injury thresholds. Occupant response was also compared to published activities of daily living data.

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Low Speed Rear End Automobile Collisions and Whiplash Injury, the Biomechanical Approach

Medicine Law & Society ◽

10.18690/10.18690/mls.12.2.1-20.2019 ◽

2019 ◽

Vol 12 (2) ◽

pp. 1-20

Author(s):

Allan F. Tencer

Keyword(s):

Whiplash Injury ◽

Biomechanical Analysis ◽

Impact Speed ◽

Low Speed ◽

Significant Damage ◽

Automobile Collisions ◽

The Impact ◽

Biomechanical Approach

The extent of injury in low speed rear end collisions is controversial. In many cases, the impact speed of the striking vehicle is low, neither car shows much if any post collision damage, and at the scene, the occupant of the struck vehicle appears uninjured. Yet many of these incidents progress to lawsuits with sometimes very significant damage and injury claims. In testimony, Plaintiff argues that the collision was significant while Defendant describes the collision as minor. A Biomechanical approach which addresses the forces in the collision and the resulting forces and kinematics of the occupant can help to resolve some of these issues. In the following, the process of a biomechanical analysis is described, using a specific example. A discussion of how courts have viewed this type of testimony is then presented.

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Vehicle and Occupant Response in Low-Speed Go-Kart Crash Tests

Volume 14: Emerging Technologies; Safety Engineering and Risk Analysis; Materials: Genetics to Structures ◽

10.1115/imece2015-53585 ◽

2015 ◽

Cited By ~ 2

Author(s):

Nick Kloppenborg ◽

Tara Amenson ◽

Jacob Wernik ◽

John Wiechel

Keyword(s):

Vehicle Performance ◽

Stationary Target ◽

Impact Speed ◽

Low Speed ◽

Frontal Impacts ◽

Hybrid Iii ◽

Oblique Impacts ◽

Acceleration Force ◽

Serious Injury ◽

Velocity Changes

Go-karts are a common amusement park feature enjoyed by people of all ages. While intended for racing, contact between go-karts does occur. To investigate and quantify the accelerations and forces which result from contact, 44 low-speed impacts were conducted between a stationary (target) and a moving (bullet) go-kart. The occupant of the bullet go-kart was one of two human volunteers. The occupant of the target go-kart was a Hybrid III 50th percentile male anthropomorphic test device (ATD). Impact configurations consisted of rear-end impacts, frontal impacts, side impacts, and oblique impacts. Results demonstrated high repeatability for the vehicle performance and occupant response. Go-kart accelerations and velocity changes increased with increased impact speed. Impact duration and restitution generally decreased with increased impact speed. All ATD acceleration, force, and moment values increased with increased impact speed. Common injury metrics such as the Head Injury Criterion (HIC), Nij, and Nkm were calculated and were found to be fairly low. These results indicate that the potential for serious injury is low during low-speed go-kart impacts.

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Asteroid and Comet Impact Speeds upon Mars: Significance for Panspermia and the Supply of Organics

International Astronomical Union Colloquium ◽

10.1017/s0252921100014718 ◽

1997 ◽

Vol 161 ◽

pp. 197-201 ◽

Cited By ~ 1

Author(s):

Duncan Steel

Keyword(s):

Probability Distributions ◽

Regions Of Interest ◽

Significant Fraction ◽

Organic Chemicals ◽

Impact Speed ◽

The Mean ◽

The Impact

AbstractWhilst lithopanspermia depends upon massive impacts occurring at a speed above some limit, the intact delivery of organic chemicals or other volatiles to a planet requires the impact speed to be below some other limit such that a significant fraction of that material escapes destruction. Thus the two opposite ends of the impact speed distributions are the regions of interest in the bioastronomical context, whereas much modelling work on impacts delivers, or makes use of, only the mean speed. Here the probability distributions of impact speeds upon Mars are calculated for (i) the orbital distribution of known asteroids; and (ii) the expected distribution of near-parabolic cometary orbits. It is found that cometary impacts are far more likely to eject rocks from Mars (over 99 percent of the cometary impacts are at speeds above 20 km/sec, but at most 5 percent of the asteroidal impacts); paradoxically, the objects impacting at speeds low enough to make organic/volatile survival possible (the asteroids) are those which are depleted in such species.

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New ultrastructural findings about Borrelia burgdorferi by cryofixation, negative staining, thin sectioning and scanning techniques

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100160467 ◽

1990 ◽

Vol 48 (3) ◽

pp. 582-583

Author(s):

S. F. Hayes ◽

M. D. Corwin ◽

T. G. Schwan ◽

D. W. Dorward ◽

W. Burgdorfer

Keyword(s):

Lyme Disease ◽

Borrelia Burgdorferi ◽

Structural Characterization ◽

Negative Staining ◽

Low Speed ◽

Thin Sectioning ◽

Ultrastructural Findings

Characterization of Borrelia burgdorferi strains by means of negative staining EM has become an integral part of many studies related to the biology of the Lyme disease organism. However, relying solely upon negative staining to compare new isolates with prototype B31 or other borreliae is often unsatisfactory. To obtain more satisfactory results, we have relied upon a correlative approach encompassing a variety EM techniques, i.e., scanning for topographical features and cryotomy, negative staining and thin sectioning to provide a more complete structural characterization of B. burgdorferi.For characterization, isolates of B. burgdorferi were cultured in BSK II media from which they were removed by low speed centrifugation. The sedimented borrelia were carefully resuspended in stabilizing buffer so as to preserve their features for scanning and negative staining. Alternatively, others were prepared for conventional thin sectioning and for cryotomy using modified procedures. For thin sectioning, the fixative described by Ito, et al.

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