Self Evolvable Hardware in Space

By Todd Huffman
Staff Writer

Beyond the gentle womb of our atmosphere space vehicles face a tough and unforgiving cosmos. Oscillations between extreme heat and cold coupled with high levels of background radiations threaten the computing systems that handle the sensitive computation of guidance, communication and many other critical tasks. Traditionally NASA and other space going organizations have relied on redundant systems to protect against computer malfunctions, having several of each computer to be brought online when one fails. This crude method may be replaced by self evolvable hardware, electronic circuits capable of reconfiguring themselves to adapt to damage or to optimize itself for its mission.

The evolution of hardware takes place when an evolvable circuit is not performing up to the desired level. This may be because of damage or a change in the environment. When a drop in performance is detected the computer uses a genetic algorithm to try out other conformations that would increase the effectiveness. By using evolution to choose the highest level of fitness the damaged areas are removed from use. One interesting aspect involved in the use of genetic algorithms is the introduction of random elements to reduce the chance of being trapped in local optima.

Self evolvable hardware offers much for the space community. As spacecraft shrink in size and weight multiple computer systems become burdensome. The ability to eliminate the excess hardware will allow for further miniaturization, lowering costs and increasing the number of missions possible. Evolvable hardware will also extend the life of a mission. This is done directly by the increased fitness of the craft and compensate for not only damage due to radiation and heat, but aging as well. In an indirect way the life of a mission will be extended because the craft will be able to synthesize new circuits to perform functions that were not included in the machines development. This added flexibility and lifespan will expand the scope and distance of space exploration.

For more information:

An interview with Adrian Stoica, a researcher in NASA’s JPL.

A good introduction to the genetic algorithms driving the evolution:

NASA’s Evolvable Hardware site (check out the Demos and Movies!!)