Motion compensation stabilizes images
Reducing mechanical-based stabilization systems on satellites can significantly decrease overall system cost, size, and weight. To do so requires replacing mechanical systems with electronic motion-compensation systems.
At Irvine Sensors (Costa Mesa, CA), such a system, based on a VME form factor, has been developed for NASA.
In operation, the single-board system calculates the relative motion in the scene from the observer`s viewpoint and compensates for motion to a fraction of a pixel. Stabilized video is output from the system with only one frame time of latency. Based on high-performance digital signal processors, the system was originally developed for a 64 ¥ 64-pixel imager operating at 1-kHz frame rates.
"Now," says David Shostak, program manager at Irvine, "the system is being reconfigured to operate on larger but slower rates of commercial television cameraswith 30 Mpixel/s data rates.
Refinement of the VME image-compensation system has led to the development of a general-purpose VME-processor-compatible Mercury Computer Systems (Chelmsford, MA) RACEway standard.
"A board dedicated specifically to electronic motion compensation is also under development for commercial cameras," says Shostak. This 4 ¥ 4-in. subsystem uses the original design but in a significantly reduced package format that can be integrated into commercial cameras. Both multichip modules and a motion-compensation ASIC are now in development.
These will further reduce the system footprint and component costs, allowing still higher levels of integration," says Shostak. For more information contact lomara@irvine-sensors.com.
