Fraunhofer-Gesellschaft - Research News 12-2001: Orbiting fire alarm

Research News 12-2001
Topic 4 Orbiting fire alarm

Dr. Sergio Montenegro
Phone: +49 30/63 92-18 78
Fax: +49 30/63 92-18 05

Prof. Dr. Peter Behr
Phone: +49 30/63 92-18 04

Fraunhofer-Institut für Rechnerarchitektur und Softwaretechnik FIRST
Kekuléstrasse 7
12489 Berlin-Adlershof, Germany

Each year, vast expanses of woodland are leveled by forest fires. All too often, the delay in recognizing the emergency from the ground makes it difficult to quell the fire before it rages out of control. More easily and quickly large fires can be identified from space. To this end, the first satellite specifically built for detecting fires was lifted into orbit some weeks ago. Designated BIRD (Bispectral Infrared Detection), the spacecraft is a product of the German Aerospace Center DLR. Shaped like a small cube measuring some 60 centimeters on all sides, it has two solar sails, weighs 94 kilos and is jam-packed with the latest electronic components. Its brain, a highly reliable onboard computer, was designed and assembled at the Fraunhofer Institute for Hardware Architecture and Software Engineering FIRST in Berlin.

One of the challenges facing satellite developers is the fact that even space does not provide a windless environment; the solar wind continuously pelts the spacecraft's electronics with its particle stream, and can even knock it out of service. On November 7, BIRD passed an early baptism of fire when the sun's ion stream shot up to one million times normal levels. BIRD autonomously recognized the errors caused by this event and made the appropriate corrections. "This was only possible because we installed four identical knot computers that control each other reciprocally," says its designer Dr. Sergio Montenegro of FIRST, not without a trace of pride. One is considered the "worker" of the bunch - it handles all of the satellite's control functions and ground communications. Another is the monitor, which checks whether the worker is performing its job optimally. If not, the monitor shuts down the worker and takes over its assignments. The computer that had been the worker performs a self-analysis and repair routine, then designates itself as the monitor, provided it doesn't discover any ongoing malfunctions. The remaining pair sits in reserve, only becoming active if the primary pair fails at the same time. "We built this exceptionally stable, self-healing computer architecture using off-the-shelf processors and components," emphasizes Montenegro. "The special electronics usually employed in spaceflight technology cost around a thousand times more."

But BIRD is not just a space-based fire alarm. Using "eyes" that are also sensitive to the visible light range of the electromagnetic spectrum, it delivers images that present a three-dimensional picture of the surface of the Earth. The two infrared bands distinguish between different coverings like cities, fields, forests or deserts.

© 2001
Fraunhofer-Gesellschaft


Research News 12-2001 Topic 4		Orbiting fire alarm

Dr. Sergio Montenegro Phone: +49 30/63 92-18 78 Fax: +49 30/63 92-18 05 Prof. Dr. Peter Behr Phone: +49 30/63 92-18 04 Fraunhofer-Institut für Rechnerarchitektur und Softwaretechnik FIRST Kekuléstrasse 7 12489 Berlin-Adlershof, Germany		Each year, vast expanses of woodland are leveled by forest fires. All too often, the delay in recognizing the emergency from the ground makes it difficult to quell the fire before it rages out of control. More easily and quickly large fires can be identified from space. To this end, the first satellite specifically built for detecting fires was lifted into orbit some weeks ago. Designated BIRD (Bispectral Infrared Detection), the spacecraft is a product of the German Aerospace Center DLR. Shaped like a small cube measuring some 60 centimeters on all sides, it has two solar sails, weighs 94 kilos and is jam-packed with the latest electronic components. Its brain, a highly reliable onboard computer, was designed and assembled at the Fraunhofer Institute for Hardware Architecture and Software Engineering FIRST in Berlin. One of the challenges facing satellite developers is the fact that even space does not provide a windless environment; the solar wind continuously pelts the spacecraft's electronics with its particle stream, and can even knock it out of service. On November 7, BIRD passed an early baptism of fire when the sun's ion stream shot up to one million times normal levels. BIRD autonomously recognized the errors caused by this event and made the appropriate corrections. "This was only possible because we installed four identical knot computers that control each other reciprocally," says its designer Dr. Sergio Montenegro of FIRST, not without a trace of pride. One is considered the "worker" of the bunch - it handles all of the satellite's control functions and ground communications. Another is the monitor, which checks whether the worker is performing its job optimally. If not, the monitor shuts down the worker and takes over its assignments. The computer that had been the worker performs a self-analysis and repair routine, then designates itself as the monitor, provided it doesn't discover any ongoing malfunctions. The remaining pair sits in reserve, only becoming active if the primary pair fails at the same time. "We built this exceptionally stable, self-healing computer architecture using off-the-shelf processors and components," emphasizes Montenegro. "The special electronics usually employed in spaceflight technology cost around a thousand times more." But BIRD is not just a space-based fire alarm. Using "eyes" that are also sensitive to the visible light range of the electromagnetic spectrum, it delivers images that present a three-dimensional picture of the surface of the Earth. The two infrared bands distinguish between different coverings like cities, fields, forests or deserts.

		© 2001 Fraunhofer-Gesellschaft