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Title: Evaluating the Performance of Marine Shock Isolation Seats in a Laboratory before Installation in a High-Speed Planing Craft

Authors: Michael Riley and Dr. Timothy Coats

Abstract: There are many references that span multiple communities of interest related to the response of shock isolation seats to wave impact loads. The communities include military operations, government applied research and acquisition, academic studies, civilian seat designers, manufactures, and high-speed boating enthusiasts. Their common goals for dealing with a harsh and demanding environment are to improve comfort, sustain mission performance, and avoid pain or injury for people seated in marine craft.

The observation that deck peak accelerations caused by wave impacts can be amplified by passive shock isolation seats is not new. Theoretical assessments and experimental observations in numerous references have identified the phenomenon, but until recently there has been no physics-based rationale for quantifying wave-impact load nor has there been an engineering methodology for laboratory testing before installation in a high-speed craft. As a result craft have been designed and shock isolation seats installed only to find out during subsequent seakeeping trials that the seats provide little to no mitigation or that they actually amplify the wave impact load. 

This paper summarizes an international approach to developing a laboratory test standard for seats based on government research and testing performed in the U.S., Canada, and the United Kingdom. The rationale for simulating a complex environment is discussed, example test data is presented, and metrics for seat performance are compared.