Page 23: of Marine News Magazine (October 2019)

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Suf? ce it to say that the combination of factors can make for an unpleasant or even dangerous ride, and a shock- mitigation industry has grown in response.

T S : S -M S GHE OLUTION HOCK ITIGATING AFETY EAR

At its core, shock-mitigating safety gear consists of a me- dium or mechanism separating an input surface, such as a boat’s deck, and a person seeking to reduce their exposure.

When all goes well, an impact is attenuated as it passes through the mechanism, resulting in a gentler motion for the person using it. But how is the attenuation achieved?

The answer, in all but the most exotic cases, comes down to a compression or material deformation of the underly- ing device, with energy dissipated as heat. And just like the cars speeding towards a brick wall, the ability of a shock- mitigating device to lessen an impact and ensure a smooth ride is tied to its stopping distance.

We gain further insight by considering the de? nition of acceleration, and it is formally de? ned as the rate of change of velocity with respect to time. When a boat collides with a wave it undergoes a velocity change due to its motion relative to the water’s surface, and so the acceleration will www.marinelink.com