Distributed Sense and Control Systems

This is a large consortium project led by UC Berkeley as part of the Multiscale Systems Center (MuSyC). This page primarily describes the work done in Richard Murray's group.

Current participants: Huan (Mumu) Xu (PhD student, ME) Necmiye Ozay (postdoc, CDS) Clemens Wiltsche (visiting student, ETH Zurich)

Previous participants:

Substantial research challenges exist in the design and verification of large-scale, complex, distributed sensing, actuation and control systems. Three topics of particular interest are the design in information flows, cooperative behavior between distributed agents, and verification of distributed, asynchronous control systems. Each of these topics relates to a difficult aspect in the proper operation of large-scale distributed system in which the temporal scales of the underlying dynamics of the systems, the rate of communications between agents, and the latency in computation and multi-threaded execution cannot be separated. The additional need to be able to rapidly design, implement and commission such systems requires new techniques in modeling, analysis, design and verification.

To approach the interlinked challenges of information flow, cooperative behavior and verification, we plan to combine tools and recent advances from control theory, networked systems and computer science. The primary tools that we expect to build on are graph theory, partial order theory, temporal logic, graph grammars, formal methods and optimization-based control. This combination of tools allows us to model and analyze complex, protocol-based control systems by using temporal logic to specify desired behavior, graph theory (in particular the graph Laplacian and other associated matrices) to model and design the information flow, graph grammars to design cooperative behavior, lattice theory and Lyapunov theory to understand convergence properties via invariant sets, and model-checking and receding horizon control to design systems whose asynchronous execution sequences satisfy a given specification. Previous results in each of these areas has demonstrated the efficacy of modeling and analysis of distributed, asynchronous sensing, actuation and control systems; future work will focus on advances required to support large-scale systems and modularity.

Objectives

• Develop algorithms, protocols and verification tools for distributed control that are aimed at optimized resource allocation between multiple agents in a decentralized and scaleable manner.
• Extend existing work in gossip algorithms, load balancing and consensus protocols to allow more sophisticated scheduling of shared resources in a dynamic environment with model-based predictions of future demand/availability.
• Application areas that will be used as drivers for the theoretical advancements include (1) power management networks in handheld devices, vehicles, buildings, manufacturing plants and geographic regions; (2) aircraft avionics and (3) cooperative control of multi-vehicle systems.

Publications

• Synthesis of Switching Protocols from Temporal Logic Specifications, Jun Liu, Necmiye Ozay, Ufuk Topcu and Richard M. Murray. American Control Conference (ACC), 2012.
• Temporal Logic Control of Switched Affine Systems with an Application in Fuel Balancing, Petter Nilsson, Necmiye Özay, Ufuk Topcu and Richard M. Murray. American Control Conference (ACC), 2012.
• On Synthesizing Robust Discrete Controllers under Modeling Uncertainty, Ufuk Topcu, Necmiye Ozay, Jun Liu and Richard M. Murray. 2012 International Conf on Hybrid Systems: Computation and Control (HSCC), 2012.
• Distributed Power Allocation for Vehicle Management Systems, Necmiye Ozay, Ufuk Topcu and Richard M. Murray. IEEE Conference on Decision and Control (CDC), 2011.
• Distributed Synthesis of Control Protocols for Smart Camera Networks, Necmiye Ozay, Ufuk Topcu, Tichakorn Wongpiromsarn, Richard M. Murray. ACM/IEEE Second International Conference on Cyber-Physical Systems, 2011.
• TuLiP: a software toolbox for receding horizon temporal logic planning, Tichakorn Wongpiromsarn, Ufuk Topcu, Necmiye Ozay, Huan Xu, and Richard M. Murray. International Conference on Hybrid Systems: Computation and Control, 2011.
• Formal synthesis of embedded control software for vehicle management systems, Tichakorn Wongpiromsarn, Ufuk Topcu and R. Murray. AIAA Infotech@Aerospace, 2011.
• Load-shedding probabilities of power systems with renewable power generation and energy storage, Huan Xu, Ufuk Topcu, Steven Low, C. Clarke and Mani Chandy. Allerton Conference on Communication, Control, and Computing, 2010.
• A simple optimal power flow model with energy storage, Mani Chandy, Steven Low, Ufuk Topcu, and Huan Xu. Conference on Decision and Control, 2010.