Distributed systems of agents linked by communication networks have access only to information from their neighbouring agents, yet they must achieve global agreement on team activities to be performed cooperatively. Examples include networked manufacturing systems, wireless sensor networks, networked feedback control systems, and the internet. Sociobiological groups such as flocks, swarms, and herds have built-in mechanisms for cooperative control wherein each individual is influenced only by its nearest neighbours, yet the group achieves consensus behaviours such as heading alignment, leader following, exploration of the environment, and evasion of predators. It is known that groups of fireflies and of crickets align their frequencies, neurons in the brain fall into patterns of interacting burst phenomena, and biological groups fall into the circadian rhythm. It was shown by Charles Darwin that local interactions between population groups over long time scales lead to global results such as the evolution of species.
This talk will review ideas of cooperative control for networked interacting teams. Included are local voting protocols, second order consensus, synchronisation of distributed interacting oscillators. Local protocols based only on interactions between neighbours lead to global optimal behaviour of distributed teams. Results from graph theory show the importance of the communication structure on the agreement reached by the networked team. Results from Lyapunov theory show the convergence to consensus values for nonlinear interaction protocols. Consensus performance generally depends on the communication graph structure and cannot be independently controlled. This can pose severe limitations on the performance of distributed systems, including slow speeds of consensus and convergence to uncontrollable values. Some protocols are described which allow a team to reach consensus agreement that is independent of the communication graph structure, and can be effectively controlled by team leaders or cooperative decision makers.
This programme is jointly organised by SIMTech and IEEE Singapore Robotics and Automation Chapter.
About the Speaker
Dr F L Lewis, Fellow IEEE, Fellow IFAC, Fellow U.K. Institute of Measurement & Control, PE Texas, U.K. Chartered Engineer, is Distinguished Scholar Professor and Moncrief-O’Donnell Chair at University of Texas at Arlington ’s Automation & Robotics Research Institute. He obtained the Bachelor's Degree in Physics/EE and the MSEE at Rice University, the MS in Aeronautical Engineering from Univ. W. Florida, and the PhD at Georgia Institute of Technology. He works in feedback control, intelligent systems, and sensor networks. He is author of 6 patents, 209 journal papers, 328 conference papers, 12 books, 41 chapters, and 11 journal special issues. He received numerous accolades, including the Fulbright Research Award, NSF Research Initiation Grant, ASEE Terman Award, and Int. Neural Network Soc. Gabor Award 2008. Received Outstanding Service Award from Dallas IEEE Section, selected as Engineer of the year by Ft. Worth IEEE Section. Listed in Ft. Worth Business Press Top 200 Leaders in Manufacturing. He was appointed to the NAE Committee on Space Station in 1995. An elected Guest Consulting Professor at both South China University of Technology and Shanghai Jiao Tong Universit, Professor Lewis is the Founding Member of the Board of Governors of the Mediterranean Control Association. Other awards include the IEEE Control Systems Society Best Chapter Award (as Founding Chairman of DFW Chapter), the National Sigma Xi Award for Outstanding Chapter (as President of UTA Chapter), and the US SBA Tibbets Award in 1996 (as Director of ARRI’s SBIR Program).
10.00am Introduction & Presentation
11.30am Refreshments & Networking
Who Should Attend
Industry professionals, R&D managers, researchers, engineers, academic staff and students.
Registration for the lecture is free of charge. Seats are available on a first-come, first-served basis.
Dr Luo Ming, Research Scientist, Email: mluo@SIMTech.a-star.edu.sg
Alice Koh, Email: alicekoh@SIMTech.a-star.edu.sg