Distributed State Machine Supervision for Long-baseline Gravitational-wave Detectors

TL;DR

This paper introduces Guardian, a distributed state machine automation platform designed for supervising complex gravitational-wave detectors like LIGO, enabling flexible, hierarchical control and rapid development for large-scale scientific experiments.

Contribution

The paper presents a novel, hierarchical, distributed state machine platform called Guardian, tailored for complex experimental control in gravitational-wave detectors and adaptable to various scientific setups.

Findings

Successfully implemented in LIGO for detector supervision

Facilitates rapid development and commissioning of complex systems

Applicable to a wide range of experimental control scenarios

Abstract

The Laser Interferometer Gravitational-wave Observatory (LIGO) consists of two identical yet independent, widely-separated, long-baseline gravitational-wave detectors. Each Advanced LIGO detector consists of complex optical-mechanical systems isolated from the ground by multiple layers of active seismic isolation, all controlled by hundreds of fast, digital, feedback control systems. This article describes a novel state machine-based automation platform developed to handle the automation and supervisory control challenges of these detectors. The platform, called \textit{Guardian}, consists of distributed, independent, state machine automaton nodes organized hierarchically for full detector control. User code is written in standard Python and the platform is designed to facilitate the fast-paced development process associated with commissioning the complicated Advanced LIGO instruments. While developed specifically for the Advanced LIGO detectors, Guardian is a generic state machine automation platform that is useful for experimental control at all levels, from simple table-top setups to large-scale multi-million dollar facilities.