Distributed Event Triggered Control, Estimation, and Optimization for Cyber-Physical Systems

• Author / Creator

  Meng, Xiangyu

• A cyber-physical system (CPS) is a system in which computational systems interact
  with physical processes. Control systems in a CPS application often include algorithms that react to sensor data by issuing control signals via actuators to the physical components of the CPS. Communication over wireless networks is the most energy-consuming function performed by the cyber components of a CPS; thus communication frequencies need to be minimized. Event triggered communication has been recognized as an efficient means to reduce communication rates between different cyber components.

  In this thesis, event triggered schemes serve as a communication protocol to mediate data exchange in distributed control, estimation, and optimization for CPSs. Firstly, it is established that event triggered communication outperforms time triggered communication based on a finite time quadratic optimal control problem for first order stochastic systems. Secondly, it is demonstrated that event triggered impulse control still outperforms periodic impulse control for second order systems in terms of mean-square state variations, while both having the same average control rate. Thirdly, a synchronization problem is considered for multi-agent systems with
  distributed event triggered control updates.
  Given an undirected and connected network topology,
  conditions on the feedback gain, the triggering parameters and
  the maximum sampling period for solving the asymptotic synchronization problem are developed based on the feasibility of
  local linear matrix inequalities (LMIs). Fourthly, a distributed state estimation method is presented through wireless
  sensor networks with event triggered communication protocols among the
  sensors. Homogeneous detection criteria and consensus filters are designed to determine broadcasting instants and perform state estimation. Lastly, an event triggered communication scheme is used to investigate distributed optimization algorithms for a network utility maximization (NUM) problem. State-dependent thresholds are established under which the proposed event triggered barrier algorithm guarantees convergence to the optimal solution to the NUM problem.

• Subjects / Keywords

  • Event triggered estimation
  • Event triggered control
  • Event triggered optimization

• Graduation date

  Fall 2014

• Type of Item

  Thesis

• Degree

  Doctor of Philosophy

• DOI

  https://doi.org/10.7939/R3H12VG5N

• License

  This thesis is made available by the University of Alberta Libraries with permission of the copyright owner solely for non-commercial purposes. This thesis, or any portion thereof, may not otherwise be copied or reproduced without the written consent of the copyright owner, except to the extent permitted by Canadian copyright law.