Need recommendations for a new Short Queen size mattress

Curious what kind of platform your mattress sits on. We had one in our last rig that was a metal frame around the edges and metal bars in a few other places in the middle. To give the mattered something ti sit on it then had a webbing done like a basket weave that worked pretty good, but the mattress funnels two people to the middle like yours. The metal bars were 1” below the outside metal frame which caused most of the issue, got some 1” aluminum tubing from Home Depot that fixed the problem.