Hierarchical, distributed and multi-agent control for ATM

• Centralized vs decentralized control

• Hierarchical control

• Free flight

• Hierarchical multi-agent control

B. De Schutter

Control Lab, Fac. ITS, Delft Univ. of Technology

http://lcewww.et.tudelft.nl/~deschutt

Centralized vs decentralized control

+ global performance– required information

bandwidth– computational

complexity– lack of scalability

+ on-line real-time control

+ modular, scalable

– locally optimal performance

– instability, conflicts

Hierarchical control

• compromise between centralized & distributed• local controllers• higher-level coordination+ safety & global performance+ tractable & scalable

Current ATM limitations• predefined corridors inefficient airspace utilization

indirect routing, non-optimal altitude & speed trajectories do not exploit favorable winds results: increased flight time + fuel consumption

• ATM complexity current ATM architecture is mainly centralized (USA) results: heavy workload for air traffic controllers,

unnecessary ground and air holding, not fault tolerant

growing demand for air travel

Future concepts [Tomlin&Sastry]

• free flight pilots determine own routes, speed, altitude restrictions imposed in congested air space:

close to airport control tower aircraft coordinate to predict and resolve

conflicts: decentralized ATM benefits: reduced flight times & fuel burned,

increased fault tolerance & capacity hierarchical multi-agent control

Hierarchical multi-agent control

Control design techniques

• decision support systems: heuristics, AI, fuzzy logic, scheduling, operations research & optimization

• multi-agent controllers: game theory, automated learning, adaptive control, model predictive control

• verification: automata, hybrid systems

References (free flight & multi-agent control)

• C. Tomlin, G. Pappas, J. Lygeros, D. Godbole, S. Sastry, G. Meyer, “Hybrid control in air traffic management systems,” Proc. 13th IFAC World Congress (IFAC'96), San Francisco, pp. 127-132, June-July 1996.

• G. Pappas, C. Tomlin, J. Lygeros, D. Godbole, S. Sastry, “A next generation architecture for air traffic management systems,” Proc. 36th IEEE Conference on Decision and Control, San Diego, pp. 2405-2410, Dec. 1997.