Modular satellites are built from cube-shaped blocks, like a construction toy. When struck by space debris, some blocks are destroyed, leaving a puncture. Engineers took inspiration from the way living tissue heals wounds. Surviving blocks detect disorder and trigger an alarm signal that travels at the speed of light through the entire structure. Each module crawls toward the hole until the edges meet, and then returns backward to its original position — without a single command, working only with its nearest neighbors.
In computer tests, a swarm of 160 blocks almost fully recovered even after losing 30% of its mass. Paradoxically, the larger the satellite, the better it patches holes — massive swarms find it easier to 'remember' the shape.
Such spacecraft could operate for decades without repairs from Earth.
Lizards regrow a lost tail from scratch, but satellites go further: they reassemble the whole from surviving parts, creating nothing new.
In Stanislaw Lem's 'The Invincible', a swarm of mechanisms self-repairs after battles — this new algorithm takes the first steps toward that self-sufficiency.