Reprogramming Satellites during Flight

Researchers in Germany have developed satellites that can be radically reconfigured in orbit. The approach could ultimately lead to multitasking satellites capable of switching, for example, from detecting pollution to searching for earthlike planets.

The researchers, led by Toshinori Kuwahara of the Institute of Space Systems at the University of Stuttgart, plan to launch a test satellite called Flying Laptop in 2012. The spacecraft’s onboard computer will be able to reconfigure its own electronic hardware. The satellite will also carry a suite of instruments and sensors including cameras, multispectral imagers, thermal infrared imagers, and GPS receivers. The research appears in the spaceflight journal Acta Astronautica.

Making satellites that can rewire themselves could save millions of dollars and reduce the amount of space junk in orbit. In addition, there could be more scientific collaboration and data gathering. Kuwahara told New Scientist that the spacecraft could even be rented out to different groups of researchers during the same mission, spreading out the cost.

Kuwahara built the satellite using microchips called field-programmable gate arrays (FPGAs). These allow the spacecraft’s electronics to be reconfigured for a particular task, instead of having a predetermined configuration that can operate only in a set way.

From the New Scientist article:

FPGAs contain logic gates that can be connected and disconnected by programmable switches. All that’s needed to move from one task to another is to retrieve the relevant logic gate connection settings from the flying laptop’s memory- or beam them to the spacecraft.

Kuwahara has to find a way to protect the FPGA circuits from charged cosmic ray particles, which can interfere with digital data and cause programming errors. He plans to use multiple back-up FPGAs all doing the same job at the same time, along with a program to decide which ones are performing correctly.

As NASA’s budget continues to get cut, building multipurpose satellites for earth science missions and other scientific data gathering–an area that the Obama administration has put emphasis on for the future–sounds like a good way to reduce the number of satellites that need to be built, thus reducing costs.