The surface that pays twice.

An embodied system that has to persist (fly for months, run for a Martian year, stay dark) is governed by a single inequality: harvest must meet demand, integrated over the mission. MMAST treats the vehicle's skin as the power plant and reads every gram against that ledger. The same multi-material stack that harvests also reshapes the signature: the radiative-cooling film that cools the cells is the IR-stealth layer; the metasurface that lifts photovoltaic gain is the radar-absorbing coat; the TENG skin that scavenges vibration is the distributed structural-health sensor. Every module pays back twice. It is one physics-informed solver over three orthogonal axes (vehicle archetype, medium, and surface module) so the same energy balance holds for a stratospheric glider, a subsea drone, and a Mars rover. The simulator is built on CadFuture, the lab's computable-world-model engine, runs headless for parameter sweeps, and renders through WebGPU.