Kontrol: KAGRA Control Python Library for VIS Control Systems

Document #:

JGW-T2011764-v3

Document type:

T

Submitted by:

Tak Lun Terrence Tsang

Updated by:

Tak Lun Terrence Tsang

Document Created:

17 Jun 2020, 11:17

Contents Revised:

17 Jun 2020, 23:22

DB Info Revised:

17 Jun 2020, 23:22

Abstract:

Kontrol is a python library for KAGRA control systems. The name ``Kontrol'' is still pronounced as ``control'' but started with a ``K'' which comes from the ``KAGRA''. The purpose of this library is to cover all control related setup in KAGRA, at least for the VIS subgroup, in hope to standardize KAGRA's control system routine. As we all know, VIS control work in KAGRA was done by various members in the VIS group and the styles of implementation have no unification in any sense because communication, protocols and consents were simply lacking. As a result, some parts of the actual system may appear cryptic to others, which might be very bad for long term. Therefore, we introduce this library as an open platform for us. As the library develops, we hope to standardize KAGRA's control system routine and enhance reproducibility and repeatability which has been lacking in some KAGRA control related systems. More importantly, we hope to improve communication and encourage discussion between colleagues through openness. Nevertheness, this library encourages automation so tedious work can be handled by the computer.

The library should cover a wide range of topics in VIS related controls, ranging from sensor and actuator diagonalization, system identification, filter design, controller synthesis and so on, essentially, everthing related to setting up the control system in KAGRA. For now, there are mainly three functions, namely, actuator diagonalization, finding sensor correction gain, and complementary filter optimization. Everything I do to the control system in KAGRA in the future will be implemented as methods in this library as time goes on. I strongly encourage related experts to co-develop this library since it will be very important to share information and techniques as KAGRA proceeds to years long operations while people come and go.

This document is not an official documentation of this library. This is just an introduction to the library serving the purpose of announcing of the existence of this library. This library was initialized under the context that the signal recycling mirrors need upgrades so the functions available do exactly what needs to be done for part of the upgrades. This document has instructions on how to install the library and how to use it in KAGRA workstations. Main functions are briefly introduced along with the theoretical concept behind. Examples are provided at the end of each introduction. Similar versions of the examples can be found in /kontrol/test/.

Files in Document:

• kontrol.pdf (336.7 kB)

Topics:

• Management
• Detector:Suspensions
• Activity:KAGRA

Authors:

• Tak Lun Terrence Tsang

Keywords:

VIS control suspension seismic

Notes and Changes:

fix typos