Spacecraft Computer Systems Colonel john e Keesee
Spacecraft Computer Systems Colonel John E. Keesee
Overview Spacecraft data processing requires microcomputers and interfaces that are functionally similar to desktop systems However, space systems require Low power. volume. and mass High reliability and fault tolerance
Overview • Spacecraft data processing requires microcomputers and interfaces that are functionally similar to desktop systems • However, space systems require: – Low power, volume, and mass – High reliability and fault tolerance
Outline · Definitions Computer system specification Estimating throughput and processor speed requirements Computer selection · Memory · Mass storage Input/Output · Radiation hardness Fault tolerance Error detection and correction Integration and test
Outline • Definitions • Computer system specification • Estimating throughput and processor speed requirements • Computer selection • Memory • Mass storage • Input/Output • Radiation hardness • Fault tolerance • Error detection and correction • Integration and test
Definitions Embedded system -a built-in processor providing real-time control as a component of a larger system often with no direct user interface Real-time processing- Handling or processing information at the time events occur or when the nformation is first created
Definitions • Embedded system – A built-in processor, providing real-time control as a component of a larger system, often with no direct user interface • Real-time processing – Handling or processing information at the time events occur or when the information is first created
Definitions(continued) Hard real-time- Requires precise timing to achieve correct results where missing at time boundary has severe consequences Soft real-time- Requires that the tasks be performed in a timely manner, where missing a time boundary results in degraded but continuous performance
Definitions (continued) • Hard real-time – Requires precise timing to achieve correct results, where missing at time boundary has severe consequences • Soft real-time – Requires that the tasks be performed in a timely manner, where missing a time boundary results in degraded but continuous performance