1. at Lewis Field Glenn Research Center Controls and Dynamics Branch Propulsion Controls and Diagnostics Research at NASA GRC – Status Report Dr. Sanjay Garg Branch Chief Ph: (216) 433-2685 FAX: (216) 433-8990 email: sanjay.garg@nasa.gov http://www.lerc.nasa.gov/WWW/cdtb Presented at: Aerospace Guidance and Control System Committee Meeting Boulder, CO, March 1, 2007

2. Aeronautics Research Mission Directorate Hypersonics Fundamental Aeronautics Program Aviation Safety Program Airspace Systems Program Supersonics Subsonic Fixed Wing Subsonic Rotary Wing Integrated Vehicle Health Management Next Generation Air Transportation System Super-Density Surface Management Integrated Resilient Aircraft Control Integrated Flight Deck Technologies Aging Aircraft NASA Aeronautics’ Program Structure

3. at Lewis Field Glenn Research Center Controls and Dynamics Branch Propulsion Control for Fundamental Aeronautics Fundamental Aeronautics Program HypersonicsSupersonics Subsonic Fixed Wing Subsonic Rotary Wing Distributed Engine Control Active Flow Control for Compression Systems Unsteady Combustion / Ejection Systems Integrated Engine and Transmission control Active Combustion Control Integrated inlet / engine control High Speed propulsion control and integration with flight control Mode Switch management

4. at Lewis Field Glenn Research Center Controls and Dynamics Branch Propulsion Control and Diagnostics for Aviation Safety Program AADIIFD Integrated Vehicle Health Management Integrated Resilient Aircraft Control Self awareness and prognosis of gas path, combustion, and overall engine state; fault-tolerant system architecture Gas Path health management ….. Damage tolerance and design for extended envelope operation; onboard hazard effects assessment, mitigation and recovery Propulsion Health Management ……… Resilient Propulsion Control ………

5. CPU / Memory Actuation electronics Sensor electronics Sensor electronics Actuation electronics Sensor electronics Actuation electronics Actuator_1 Sensor_1 Sensor_ j Actuator_n Sensor_2 Actuator_2 Communication Power BUS FADEC Current Engine Control Architecture Centralized with each sensor/actuator directly connected to FADEC

7. at Lewis Field Glenn Research Center Controls and Dynamics Branch Centralized Engine Control Pros: –Works, reliable, well-understood, experience, comfort level Cons: –Expensive, inflexible, in the future will become a limiting factor in engine performance –Wire harness weight forces the FADEC to be co- located on the engine structure –Co-located FADEC requires environmental hardening (thermal, mechanical) further increasing weight and cost. –Complicates fault detection and isolation

8. CPU / Memory Actuator_1 Sensor_1 Sensor_ j Actuator_n Sensor_2 Actuator_2 Communication Power FADEC Distributed Engine Control Communication Actuation electronics Sensor electronics Sensor electronics Actuation electronics Sensor electronics Actuation electronics BUS

9. at Lewis Field Glenn Research Center Controls and Dynamics Branch Distributed Engine Control Topologies: –Star (point to point), Ring or bus (daisy chain) –Wired or wireless Pros: –Known to work well in other industries, much less expensive (initial and overall cost), very flexible Cons: –Communication unknowns and deterministic behavior –Overall increased complexity –Requires new technologies, i.e., high temperature electronics