Accession Number : ADA309783

Title :   Effects of Seat Cushions on Human Vibration Response.

Descriptive Note : Annual rept. 1 Dec 94-1 Aug 95,

Corporate Author : ARMSTRONG LAB WRIGHT-PATTERSON AFB OH CREW SYSTEMS DIRECTORATE

Personal Author(s) : Smith, Suzanne D.

PDF Url : ADA309783

Report Date : SEP 1995

Pagination or Media Count : 35

Abstract : Discomfort, performance degradation, and increased health risk have been associated with prolonged exposures to vibration occurring in the operation of civilian and military air, ground, and water vehicles. While an increasing number of females are selecting these occupations, the existing vibration standards and exposure limits are based on the male population. The objective of this study was to compare the biodynamic responses of females and males exposed to whole-body vibration. Seating configurations included the rigid seat and two military aircraft seat cushions. This progress report presents the results for the period 1 Dec 94 - 1 Aug 95 which includes a comparison of the resonance behaviors observed in the driving-point impedance and chest transmissibility measurements. While the frequency location of the peak or primary response (4 and 8 Hz) was not significantly affected, the peak impedance magnitude results indicated that the female responses were significantly less than the male responses and could not be attributed to differences in body weight alone. The chest transmissibility results were more variable but there was a tendency for the horizontal chest motion to be lower and the vertical chest motion to be higher in the females as compared to the males. The cushions increased the transmission of vibration in the majority of subjects with the smaller females being the most sensitive to cushion effects.

Descriptors :   *VIBRATION, *MILITARY VEHICLES, *EXPOSURE(PHYSIOLOGY), *SEATS, *CUSHIONING, *PADS(CUSHIONS), *POSTURE(PHYSIOLOGY), FREQUENCY, POSITION(LOCATION), RISK, DEGRADATION, HUMANS, AIR, WATER, HEALTH, SENSITIVITY, POPULATION, TRANSMITTANCE, LIMITATIONS, RESPONSE, CONFIGURATIONS, MALES, BEHAVIOR, HORIZONTAL ORIENTATION, THORAX, RIGIDITY, BODY WEIGHT, FEMALES, BIODYNAMICS.

Subject Categories : Stress Physiology
      Logistics, Military Facilities and Supplies

Distribution Statement : APPROVED FOR PUBLIC RELEASE