Online State Estimation for Supervisor Synthesis in Discrete-Event Systems with Communication Delays and Losses

TL;DR

This paper presents a new framework and online algorithm for accurate state estimation in networked discrete-event systems with communication delays and losses, enabling safer supervisor synthesis.

Contribution

It introduces a novel framework and online estimation method that improve state accuracy for supervisor synthesis in networked DESs with delays and losses.

Findings

The proposed estimation algorithm accounts for control effects and communication issues.

It achieves more accurate state estimation compared to existing methods.

The framework facilitates synthesis of maximally permissible and safe supervisors.

Abstract

In the context of networked discrete-event systems (DESs), communication delays and losses exist between the plant and the supervisor for observation and between the supervisor and the actuator for control. In this paper, we first introduce a new framework for supervisory control of networked DESs. Under the introduced framework, we address the state estimation problem for supervisor synthesis of networked DESs with both communication delays and losses. The estimation algorithm considers the effect of the controls imposed on the system. Additionally, the estimation algorithm is based on the control decisions available up to the moment, and all the future control decisions are assumed to be unknowable. Two notions, called "observation channel configuration" for tracking observation delays and losses and "control channel configuration" for tracking control delays and losses, are defined. Then, we introduce an online approach for state estimation of the controlled system. Compared with the existing approach, the proposed approach under the introduced framework can estimate the state of the controlled system more accurately. As an application of the proposed approach, we finally show that the existing methods can be easily applied to synthesize maximally permissible and safe networked supervisors.