Page 282 - Biomedical Engineering and Design Handbook Volume 1, Fundamentals

CHAPTER 11

VIBRATION, MECHANICAL

SHOCK, AND IMPACT

Anthony J. Brammer
Biodynamics Laboratory at the Ergonomic Technology Center,
University of Connecticut Health Center, Farmington,
Connecticut and Institute for Microstructural Sciences,
National Research Council, Ottawa, Ontario, Canada

Donald R. Peterson
University of Connecticut School of Medicine, Farmington,
Connecticut

11.1 INTRODUCTION 259 11.4 COUNTERMEASURES 278
11.2 PHYSICAL MEASUREMENTS 264 REFERENCES 283
11.3 MODELS AND HUMAN
SURROGATES 270

11.1 INTRODUCTION

Time-varying forces and accelerations occur in daily life, and are commonly experienced, for example,
in an elevator and in aircraft, railway trains, and automobiles. All of these situations involve motion
of the whole body transmitted through a seat, or from the floor in the case of a standing person,
where the human response is commonly related to the relative motion of body parts, organs, and tissues.
The vibration, shocks, and impacts become of consequence when activities are impaired (e.g., writing
and drinking on a train, or motion sickness), or health is threatened (e.g., a motor vehicle crash).
Equally important are exposures involving a localized part of the body, such as the hand and arm
(e.g., when operating a hand tool), or the head (e.g., impacts causing skull fracture or concussion).
In this chapter, methods for characterizing human response to vibration, shock, and impact are
considered in order to prescribe appropriate countermeasures. The methods involve data from experi-
ments on humans, animals, and cadavers, and predictions using biodynamic models and manikins.
Criteria for estimating the occurrence of health effects and injury are summarized, together with
methods for mitigating the effects of potentially harmful exposures. There is an extensive literature
on the effects of vibration, shocks, and impacts on humans (Brammer, in press; Mansfield, 2005;
Griffin, 1990; Nahum et al., 2002; Pelmear et al., 1998).

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