Autonomous Formation Flight MIT Course 16.886, Spring 2004 Air Transportation Systems Architecting Greg Larson Program Manager Boeing phantom Works Gerard Schkolnik Program Manager NASA DFRC o感e BENT Autonomous Formation Flight Page 1
Autonomous Formation Flight MIT Course 16.886, Spring 2004 Air Transportation Systems Architecting Greg Larson Program Manager Boeing Phantom Works Gerard Schkolnik Program Manager NASA DFRC Page 1 Autonomous Formation Flight Program NAS4-00041 TO-104
Overview Autonomous Formation Flight: NASA RevCo Program Boeing is currently engaged with NASA Dryden Flight Research Center on a technically ambitious project, Autonomous Formation Flight(AFF). The projects primary goal is to investigate potential benefits of flying aircraft in the aerodynamic wake vortex emanating from a lead aircraft s wing tip. Initial analytic studies predict that a trailing aircraft may the lead 's wake vortex. The technical challenge is to be able to find the optimal positioner experience drag reductions of 10% or more by gaining additional lift in the updraft portion of within the vortex to fly, then hold that position consistently in what is an extremely turbulent flow field. We know that pilots have been able to do this in the past, but the task involves a very high workload. The Autonomous Formation Flight system marries an extremely robust flight control and guidance system with a close-coupled GPS/MU placed on two F-18s. Inter-shjp communication allows the multple GPS/MU systems to share state data and through and extended Kalman filter technique, they yield a differential carrier phase solution. They resolve the relative position accuracy between the aircraft in formation to less than 10 cm Through shared state data, the guidance systems aboard both F-18s resolve coordinated trajectories that permit the aircraft to maintain formation. The trailing aircraft is thus capable of maintaining its position within the lead aircraft's wing tip vortex with extremely high accuracy The implications and applications of this technology are far reaching not just for fuel economy but for other future applications such as aerial refueling, aircraft logistics, air traffic control, and carrier landing systems BELT Autonomous Formation Flight Page 2
Overview Autonomous Formation Flight: NASA RevCo Program Boeing is currently engaged with NASA Dryden Flight Research Center on a technically ambitious project, Autonomous Formation Flight (AFF). The project’s primary goal is to investigate potential benefits of flying aircraft in the aerodynamic wake vortex emanating from a lead aircraft’s wing tip. Initial analytic studies predict that a trailing aircraft may experience drag reductions of 10% or more by gaining additional lift in the updraft portion of the lead’s wake vortex. The technical challenge is to be able to find the optimal position within the vortex to fly, then hold that position consistently in what is an extremely turbulent flow field. We know that pilots have been able to do this in the past, but the task involves a very high workload. The Autonomous Formation Flight system marries an extremely robust flight control and guidance system with a close-coupled GPS/IMU placed on two F-18s. Inter-ship communication allows the multiple GPS/IMU systems to share state data and through and extended Kalman filter technique, they yield a differential carrier phase solution. They resolve the relative position accuracy between the aircraft in formation to less than 10 cm. Through shared state data, the guidance systems aboard both F-18s resolve coordinated trajectories that permit the aircraft to maintain formation. The trailing aircraft is thus capable of maintaining its position within the lead aircraft’s wing tip vortex with extremely high accuracy. The implications and applications of this technology are far reaching, not just for fuel economy but for other future applications such as aerial refueling, aircraft logistics, air traffic control, and carrier landing systems. Page 2 Autonomous Formation Flight Program NAS4-00041 TO-104
Special Acknowledgements& References To Technical Papers Jake Vachon (NASA TM 2003-2107341) Ronald Ray (NASA TM 2003-2107341) Kevin Walsh(NASA TM 2003-2107341) Kimberly EnniX(NASA TM 2003-2107341) Ron Ray NASA TM 2002 210723 Brent Cobleigh(NASA TM 2002 210723 Jake Vachon (NASA TM 2002 210723 Clint St John(NASA TM 2002 210723) Eugene Lavretsky(AIAA-2002-4757) Glenn Beaver(NASA TM-2002-210728) Peter Urschel (NASA TM-2002-210728 Curtis E. Hanson(NASA TM-2002-210728, NASA TM-2002-210729) Jennifer Hanson (AlAA-2002-3432) Jack Ryan( NASA TM-2002-210729 Michael J. Allen(NASA TM-2002-210729) StevenR. Jacobson(NASA TM-2002-210729) o感 BELT Autonomous Formation Flight Page 3
Special Acknowledgements & References To Technical Papers Jake Vachon (NASA TM 2003-2107341) Ronald Ray (NASA TM 2003-2107341) Kevin Walsh (NASA TM 2003-2107341) Kimberly Ennix (NASA TM 2003-2107341) Ron Ray (NASA TM 2002 210723) Brent Cobleigh (NASA TM 2002 210723) Jake Vachon (NASA TM 2002 210723) Clint St. John (NASA TM 2002 210723) Eugene Lavretsky (AIAA-2002-4757) Glenn Beaver (NASA TM-2002-210728) Peter Urschel (NASA TM-2002-210728) Curtis E. Hanson (NASA TM-2002-210728, NASA TM-2002-210729) Jennifer Hanson (AIAA-2002-3432) Jack Ryan (NASA TM-2002-210729) Michael J. Allen (NASA TM-2002-210729) Steven R. Jacobson (NASA TM-2002-210729) Page 3 Autonomous Formation Flight Program NAS4-00041 TO-104
Presentation Outline Project Summary Objectives Theory Experiment Design Phase 0 Flight Test Phase 1 Flight test · Cruise mission Demonstration Performance Seeking Control Aerial Refueling Concluding Remarks Test flights began in August and culminated with a drag- reduction demonstration flight in the beginning of December 2001 A total of 28 flights were accomplished, and the full test point matrix was accomplished at both M=0. 56, 25000 feet, and M=0. 86, 36000 feet 415 test points were flown 5 Project Pilots were involved in AFF Phase One Risk Reduction o感 BELT Autonomous Formation Flight Page 4
Presentation Outline • Project Summary • Objectives • Theory • Experiment Design • Phase 0 Flight Test • Phase 1 Flight Test • Cruise Mission Demonstration • Performance Seeking Control • Aerial Refueling • Concluding Remarks • Project Summary • Objectives • Theory • Experiment Design • Phase 0 Flight Test • Phase 1 Flight Test • Cruise Mission Demonstration • Performance Seeking Control • Aerial Refueling • Concluding Remarks Test flights began in August and culminated with a drag-reduction demonstration flight in the beginning of December 2001. A total of 28 flights were accomplished, and the full test point matrix was accomplished at both M=0.56, 25000 feet, and M=0.86, 36000 feet. 415 test points were flown 5 Project Pilots were involved in AFF Phase One Risk Reduction Page 4 Autonomous Formation Flight Program NAS4-00041 TO-104
Autonomous Formation Flight tackground Many bird species fly in"V formation to take advantage of the up-wash field generated by adjacent birds, resulting in less nergy expended Analytical studies and recent AFF flight tests validate these observations AFF Objectives Validate drag reduction concept and prediction tools of a system of aircraft in formation in the fight environment Develop and evaluate sensor and control methodologies for Approach autonomous close formation flight Flight test autonomous station keeping control laws of pair of F-18 Validate drag benefits and wing tip vortex behavior using piloted flight tests Develop and validate advanced relative GPS system capable of 10 cm relative position accuracy Integrate updated sensors and advanced formation control laws to perform autonomous station keeping within the vortex wake of a lead aircraft Benefits Potential commercial fuel savings of $o 5 to 1 million per year per trailing aircraft Application to UAV Swarming, Aerial Refueling BELT Autonomous Formation Flight Page 5
Autonomous Formation Flight Autonomous Formation Flight • Background – Many bird species fly in “V” formation to take advantage of the up-wash field generated by adjacent birds, resulting in less energy expended. – Analytical studies and recent AFF flight tests validate these observations. • AFF Objectives – Validate drag reduction concept and prediction tools of a system of aircraft in formation in the flight environment – Develop and evaluate sensor and control methodologies for autonomous close formation flight • Approach – Flight test autonomous station keeping control laws of pair of F-18 aircraft. – Validate drag benefits and wing tip vortex behavior using piloted flight tests. – Develop and validate advanced relative GPS system capable of 10 cm relative position accuracy. – Integrate updated sensors and advanced formation control laws to perform autonomous station keeping within the vortex wake of a lead aircraft. • Benefits – Potential commercial fuel savings of $0.5 to 1 million per year per trailing aircraft. – Application to UAV Swarming, & Aerial Refueling. Page 5 Autonomous Formation Flight Program NAS4-00041 TO-104