Swarming spacecraft to self-destruct for greater good

Future space probes that operate in cooperative swarms must commit hara-kiri if they begin to fail and risk damaging their comrades, says a recent patent application by NASA.

The agency foresees a day when space missions are undertaken not by one large spacecraft but by swarming formations of much smaller, cheaper ones. Such craft could collectively provide a "floating optics" system for a space telescope comprising separate craft flying in formation, for instance.

However, should one spacecraft in such a swarm begin to fail and risk a calamitous collision with another, it must sense its end is nigh and put itself on a course that takes it forever away from the swarm – for the greater good of the collective.

Failing that – perhaps because it has too little fuel to move – it must "passivate" itself by deactivating all its systems. This would mean discharging its batteries so as to pose no risk of shock in a collision, and venting any last vestiges of fuel that could explode in a crash. Then its neighbours would be programmed to navigate around the lifeless satellite.

Fiery end

To make this altruistic behaviour possible, NASA engineers Michael Vinchey and Emil Vassev at the Goddard Space Flight Center in Greenbelt, Maryland, want to patent the idea of control software that autonomously guides all the craft in a mission while constantly checking up on critical electronic systems in each one.

When certain failure modes are sensed, the craft must "self-sacrifice voluntarily by transformation or self-destruction", the application says. The inventors liken this to the way bee colonies operate, with the workers cooperating to ensure that the mission – that is, reproduction by the queen – succeeds at all costs, even at their own peril.

It's not the first time spacecraft have been put forward for the ultimate sacrifice. The Surrey Space Centre in Guildford, UK, is designing a probe solar sail that can be raised at the end of its mission to brake it against the upper atmosphere, leading it to burn up. And the Japan Aerospace Exploration Agency (JAXA) has proposed "suicide satellites" that would attach to large chunks of space junk and fire a rocket to propel the junk into the atmosphere – again, to meet a fiery fate. ...

via Swarming spacecraft to self-destruct for greater good - space - 06 September 2010 - New Scientist.