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The Pathfinder revision was a basic flat plate with a centering ring welded on.
Rev 1.1: Pathfinder round 2
Thicker bulkhead to accommodate loads of main chute opening (based on analysis done below):
Sim results were good for 2000lbs and showed a displacement of ~.2mm.
Rev. 2: Hermes
All load from main and drogue parachute opening will go through the Payload bulkhead (whereas we expect all reaction load from piston separation to go through the Avionics bulkhead). While we are currently working to qualify an upper bound on deployment forces, we ran some simulations at 3000lbs (an over-estimate) in order to determine an approximate thickness. In these simulations, we applied the load evenly between the four bolt holes and fixed the lower surface of the upper lip as a fixed geometry. Part material was Aluminum 6061. All runs were performed under the finest basic mesh but we did not refine the mesh for bolt holes.
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