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REAL TIME Live, Full-scale Giga-Places Peta-Bytes, Tera-OPS Femto-time Learn Observe Interoperable, pervasive networking Ubiquitous sensors 7/10/11 Now Digitized: Sense/Observe Collect/Distribute Analyze Simulate Decide Act Real-time, massive analysis Automated learning Vast, evolving knowledge stores What is “real time”? What If? Now Then Real Time Systems: Live, always-on, reactive, interactive, stable, controllable, adaptive What If? What If? Now Then Rate-1 7/10/11 Rate-1 Later Rate-1 Time Frames and Operation Rates Observation time – measure, discriminate Analysis time – communicate, contextualize, understand Decision time – choose, formulate, distribute Action time – energize,drive 7/10/11 Sample rates vary with applications Pico to milliseconds Speed of a process Days to weeks Decades Stock trading incl’d programmed trading Automobile controls engines to driverless control Water resources measurement, modeling & controls SCIENCE Surveillance Memory recall Climate change Content distribution Power grid demand It all begins with simulation… Sensors* Simulator with Human *Sensors may be people Model of System e.g. airplane MIT Whirlwind (c1951) first real time computer. Begot SAGE (Semi-Automatic Ground Environment) Sample rate versus utility Pico to milliseconds Speed of a process Days to weeks Decades Stock trading incl’d programmed trading Automobile controls engines to driverless control; Power grid demand Water resources measurement, modeling & controls SCIENCE Surveillance Memory recall Climate change Content distribution Wes Clark, Lincoln Laboratory, and LINC, first PC. LINC: Laboratory Instrument Computer c. 1962 Real time processing for bio-medical research. Real time Sensing e.g. laboratory control, simulators Sensors* REAL WORLD System *Sensors may be people Observers, Model Builders e.g. Scientists LINC 2007 Vintage Computer Fair (At age 45 … turns 50 next year) Some other real time computers Whirlwind: Bright Boys 1962 LINC that influenced PDP-5 8/1963 PDP-5 for interfacing a Canadian research reactor to a PDP-4 (controller) RT-11 from OS/8 begot CPM >> DOS RSX-11 Sensing… Observations by human operators Sensors* REAL WORLD System *Sensor/effector may be people Sharing of data To effect change Real time Control Plain old closed loop control Model of REAL WORLD System Advice (t+1) Controller Sensors* REAL WORLD System Effectors* *Sensor/effector may be people (Processing, policies and people) Real time and Control with/wo Real World Modeling Model of REAL WORLD System Advice (t+1) Delays and Noise Sensor s* WORLD REAL System Effector s* *Sensor/effector may be people Delays and Noise Controller (Processing, policies and people)
