Computer Controlled Systems: Theory and Design

This paper investigates the distributed adaptive event-triggered consensus control for a class of nonlinear agents Each agent is subject to input saturation Two kinds of distributed event-triggered control scheme are introduced, one is continuous-time-based event-triggered scheme and the other is sampled-data-based event-triggered scheme Compared with the traditional event-triggered schemes in the existing literatures, the parameters of the event-triggered schemes in this paper are adaptively adjusted by using some event-error-dependent adaptive laws The problem of simultaneously deriving the controller gain matrix and the event-triggering parameter matrix, and tackling the saturation nonlinearity is cast into standard linear matrix inequalities problem A convincing simulation example is given to demonstrate the theoretical results

Adaptive periodic event-triggered consensus for multi-agent systems subject to input saturation

Summary

This paper focuses on the analysis and the design of event-triggering scheme for discrete-time systems. Both static event-triggering scheme (SETS) and adaptive event-triggering scheme (AETS) are presented for discrete-time nonlinear and linear systems. What makes AETS different from SETS is that an auxiliary dynamic variable satisfying a certain difference equation is incorporated into the event-triggering condition. The sufficient conditions of asymptotic stability of the closed-loop event-triggered control systems under both two triggering schemes are given. Especially, for the linear systems case, the minimum time between two consecutive control updates is discussed. Also, the quantitative relation among the system parameters, the preselected triggering parameters in AETS, and a quadratic performance index are established. Finally, the effectiveness and respective advantage of the proposed event-triggering schemes are illustrated on a practical example. Copyright © 2016 John Wiley & Sons, Ltd.

Adaptive event‐triggered control for nonlinear discrete‐time systems

This paper is concerned with robust ${H_{\infty }}$ self-triggered control of networked systems. The system considered here includes parameter uncertainties, packet dropouts, and time delays. The time delay is described in a stochastic way, which takes a value from a given finite set. In order to compensate for the existence of deterministic packet dropouts, a new self-triggered control scheme is proposed. The main feature of the proposed self-triggered control strategy is that the next control task is predicted based on the self-triggered technique, in which the predicted event interval is divided equally for the sake of packet dropouts. The triggered condition is developed to ensure the stability of the uncertain sampled system by utilizing an uncertain algebraic Riccati equation and the comparison principle. Finally, an example of the inverted pendulum of a cart is provided to illustrate the effectiveness of the proposed results.

Robust $H_{\infty }$ Self-Triggered Control of Networked Systems Under Packet Dropouts

https://hal.archives-ouvertes.fr/hal-01344252/document

LQ-based event-triggered controller co-design for saturated linear systems

This technical note considers event-triggering conditions and controller synthesis approaches for delayed linear systems. Optimization problems for minimizing the upper bound of quadratic cost functions are formulated in the form of linear matrix inequalities (LMIs). By solving the optimization problems a unique control gain can be obtained. The performance considered in this technical note includes a linear quadratic cost function for quantifying the control performance and average event times at which the control input must be updated for quantifying the transmission reductions. Comparisons with other approaches in the literature are given to demonstrate the advantages with respect to the two performance indices. Furthermore, an experimental implementation of the proposed methods in an inverted pendulum system shows the applicability and effectiveness in real world.

Suboptimal Event-Triggered Control for Time-Delayed Linear Systems

Summary
This paper considers event-triggering controller design for directly observable discrete-time linear systems subject to bounded disturbances. The main control objective is diminishing the influence aroused by the disturbances despite a reduction of the communication. Criteria are given to design feedback controllers in order to guarantee that systems are uniformly ultimately bounded in an ellipsoidal-positive invariant set, which is used as an estimate of control performance for disturbance rejection. An optimization for minimizing the ellipsoidal-positive invariant set is achieved by synthesizing the feedback control gain and the given event-triggering conditions in LMIs. The effectiveness and applicability of the controller are illustrated by simulations and experimental implementations. Copyright © 2015 John Wiley & Sons, Ltd.

Event-triggered control for discrete-time linear systems subject to bounded disturbance

http://www.nt.ntnu.no/users/skoge/prost/proceedings/ifac2014/media/files/0255.pdf

Event-Triggered Control for Linear Systems Subject to Actuator Saturation

For networked embedded control systems (NECSs) besides control performance an efficient usage of computation and communication resources is crucial. This paper presents a novel event-based codesign concept for NECSs. The codesign concept involves a joint design of a control law, a scheduler, and an event generator. The control law serves for improving control performance, the scheduler and the event generator for an efficient usage of the limited resources. The codesign problem is formulated as a linear matrix inequality (LMI) problem which can be solved efficiently. The developed theory is evaluated through a simulation for networked embedded control of a set of inverted pendulums. Noteworthy, the codesign concept is generally applicable to discrete-time switched linear systems.

Event-based control and scheduling codesign of networked embedded control systems

This paper addresses the control and scheduling of embedded control systems with shared computation resources. The holistic system consisting of several linear plants, which are controlled by one single processor, is modeled as a switched control system. Based on quadratic Lyapunov function a method is introduced to design jointly schedule and control, which guarantees stability of all plants controlled by the processor. The proposed strategy is formulated as a constrained optimization problem, which firstly allows checking the feasibility of the stabilization of all plants by controlling them by one processor. Moreover, the solution of the constrained optimization problem contains the control gain and the necessary parameters for an appropriate online scheduling. The method is illustrated by an example.

Sven Reimann

Papers

Suboptimal Event-Triggered Control for Time-Delayed Linear Systems

Event-triggered control for discrete-time linear systems subject to bounded disturbance

Event-Triggered Control for Linear Systems Subject to Actuator Saturation

Event-based control and scheduling codesign of networked embedded control systems

A novel control-schedule codesign method for embedded control systems