Propulsion Controls and Diagnostics Research at NASA GRC – Status Report

1. 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 Controls and Dynamics Branch

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

3. Propulsion Control for Fundamental Aeronautics Fundamental Aeronautics Program Subsonic Fixed Wing Subsonic Rotary Wing Supersonics Hypersonics • Distributed Engine Control • Active Flow Control for Compression Systems • Unsteady Combustion / Ejection Systems • Integrated Engine and Transmission control • Active CombustionControl • Integrated inlet / engine control • High Speed propulsion control and integration with flight control • Mode Switch management Controls and Dynamics Branch

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

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

7. 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 Controls and Dynamics Branch

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

9. 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 Controls and Dynamics Branch