Charlot Lab · Institute for Physical AI @ BMI · the certificate, made visible
A dozen bodies must cross to the far side of the ring — every path meets in the middle. Turn the certificate off and each body drives greedily at its goal: they pile into the centre and collide. Turn it on and every body runs the same rule — before it moves, keep every gap to a neighbour wider than its own braking distance — with no central planner and nothing shared but what each can see. They thread the crossing and never touch. Safety is a property each body holds locally; the local guarantees compose into a safe collective. This is one face of the certificate doctrine — the same braking barrier that keeps an arm clear of a person, now held by a fleet.
What you are watching. Each certified body, every step, checks its most-binding neighbour: if it is closing faster than reciprocal braking could open the gap, it brakes — and because slowing down widens every gap at once, that one move is safe against all neighbours together. Above that floor it eases right to keep flowing. The honest cost is throughput, not safety: crowd the ring and more bodies slow and yield at the centre — collisions stay at zero, but some finish later (a right-of-way rule buys the flow back). Turn the certificate off to see the alternative: greedy bodies, each individually sensible, collide where their plans overlap. Every number here is computed live in your browser from the same rule verified offline (0 collisions at N up to 12). Scope: 2-D point bodies, sensed relative state, symmetric braking authority — a demonstrator, not a fielded fleet. More: The Certificate Doctrine · The No-Harm Certificate.