Microcellular Polyurethane

Look at the railway industry and find out what it does to prevent abrupt collisions between moving vehicles and fixed obstructions.

I can tell you what they do from first had experience. They hope they miss you, as they go skidding down the tracks. When I called their HQ to complain that they didn't blow their horn, they referred to me as 'the near miss, from South Side' before I was able to ask they the question.

do a search on "Jounce Bumpers"

many companies make them freundenberg-nok is one

you can mostlikely find one off the shelf and save the tooling

good luck

cbs