Distributed Event-based State Estimation

TL;DR

This paper introduces an event-based distributed state estimation method for networked control systems that reduces communication while maintaining estimation accuracy and stability, demonstrated through theoretical analysis and simulations.

Contribution

It presents a novel event-based protocol for distributed state estimation that guarantees bounded errors and extends to control, improving communication efficiency over traditional methods.

Findings

Reduces communication in distributed estimation systems.

Guarantees bounded estimation errors under bounded disturbances.

Outperforms periodic schemes in simulation by lowering communication needs.

Abstract

An event-based state estimation approach for reducing communication in a networked control system is proposed. Multiple distributed sensor-actuator-agents observe a dynamic process and sporadically exchange their measurements and inputs over a bus network. Based on these data, each agent estimates the full state of the dynamic system, which may exhibit arbitrary inter-agent couplings. Local event-based protocols ensure that data is transmitted only when necessary to meet a desired estimation accuracy. This event-based scheme is shown to mimic a centralized Luenberger observer design up to guaranteed bounds, and stability is proven in the sense of bounded estimation errors for bounded disturbances. The stability result extends to the distributed control system that results when the local state estimates are used for distributed feedback control. Simulation results highlight the benefit of the event-based approach over classical periodic ones in reducing communication requirements.