Earthquake Research Satellite Demonstrates Value of PC/104
Small size, light weight, lower power consumption, and high integration are key
to realizing ultra-miniature data collection satellite
QuakeSat, an innovative and ultra-compact satellite designed to search for earthquake precursor signals, is using the Prometheus integrated PC/104 CPU board from Diamond Systems Corp. (Newark, CA) as the heart of its electronics system. QuakeSat was designed by QuakeFinder, a joint venture between satellite services provider Stellar Solutions (Palo Alto, CA), Lockheed Martin, and the Space Systems Development Laboratory at Stanford University.
The QuakeSat is an excellent example of what can be achieved using PC/104 embedded systems technology. A satellite application involves extreme design restrictions that limits the choices of components: Size, weight, power consumption, and ruggedness are of paramount concern. Only PC/104 was able to meet these criteria and provide a suitable computing platform for the QuakeSat electronics.
Mission Background and Objectives
QuakeSat is based on the recent discovery that earthquakes produce very small but measurable disturbances in the Earth’s magnetic field. These disturbances result from large-scale geological effects in the vicinity of the earthquake and appear as Extremely Low Frequency (ELF) magnetic field fluctuations in the range of 0.05 to 4.0 Hz. These ELF signals have been shown to occur between several hours up to several days prior to a large earthquake, potentially providing sufficient warning time to minimize potential damages to property, injuries, and loss of life.
Until now, earthquakes have been the only natural disaster unable to be accurately predicted. However, they occur with alarming frequency: A magnitude 6.0 quake occurs about once a week somewhere in the world, while a magnitude 7.0 or greater quake occurs on average once a month. QuakeSat’s mission is to prove the ability to reliably detect the tell-tale ELF signals from space and use them to predict earthquakes around the world. QuakeSat is expected to launch in July, 2003 and operate for about 6 months in orbit.
The QuakeSat measures a tiny 4” x 4” x 12”. It is designed to fit inside an ultra-miniature satellite enclosure that mounts in a Russian rocket decommissioned as a result of the former START talks. This severe size restriction limited the choices for off-the-shelf CPU boards. Diamond Systems’ Prometheus CPU was chosen because it met these key criteria:
- PC/104 form factor: Small size (3.6” x 3.8”) fits inside the small enclosure
- Integrated design: Combining the processor and data acquisition functions on a single board reduces the size and weight of the CPU and enables more electronics to fit in the satellite
- Low power consumption: Power consumption of less than 5 watts minimizes the drain on the satellite’s solar-collector power system
- Rugged design: Temperature and vibration immunity enables the satellite to survive launch and operate in a space environment with extreme temperature swings
Prometheus PC/104 CPU
The Prometheus CPU is based on the ZF Micro (National Semiconductor) ZFx86 CPU-on-a-chip, featuring high integration and low power consumption. The board includes processor, memory, Ethernet, serial ports, IDE, and a full analog and digital I/O circuit supported with driver software for multiple operating systems. The Prometheus combines two boards (CPU and I/O) into a single board to reduce the size and weight of an embedded system by 50 percent. The ZFx86 processor, along with selection of low-power components, limits the total power consumption to 5 watts. Power consumption in this instance was further reduced by depopulating unused circuitry from the board. QuakeSat runs Linux from a solid state IDE flashdisk module that mounts directly onto the Prometheus board for maximum compactness and ruggedness.
“We are extremely proud to be part of this important scientific mission for two reasons,” said Jonathan Miller, Diamond Systems president. “First, Diamond Systems has always been a strong believer in the value of PC/104 in the industrial and scientific markets. The QuakeSat application shows what is possible when a skilled design team takes full advantages of all the benefits that PC/104 has to offer. But second, and more importantly, this mission has the potential to provide great service to mankind, and so it gives us great honor to play a central role in this project.”
QuakeFinder is an R&D spinoff from Stellar Solutions in Palo Alto, CA. The company has been actively building a network of ground-based ELF monitoring systems near major earthquake faults in California. The QuakeSat project is an extension of this ongoing project. QuakeSat’s goal is to expand ELF monitoring to provide worldwide coverage and to increase the available statistical data on ELF signals.
About Diamond Systems
Diamond Systems Corporation was founded in 1989, was one of the first computer peripheral manufacturers to adopt the PC/104 standard for embedded control systems. Today the company is a leading supplier of PC/104 CPU, data acquisition, serial port, and power supply modules to customers designing embedded control systems. In addition to standard products, the company also designs custom I/O boards for OEM embedded systems designers.
For more information on QuakeSat and the QuakeFinder project, visit http://www.quakefinder.com.
For more information on Diamond Systems and the Prometheus CPU, visit http://www.diamondsystems.com.
(c) 2003 Diamond Systems Corporation. Diamond Systems and the diamond logo are trademarks of Diamond Systems Corporation. All other brand or product names are trademarks or registered trademarks of their respective holders.