This PDF file contains the front matter associated with SPIE Proceedings Volume 13099, including the Title Page, Copyright information, Table of Contents, and Conference Committee information.

Lentil is a Python package for developing high-performance diffraction simulations. Lentil provides an easy to use framework for modeling optical systems and simulating the wave propagation of light through them. Traditional Fourier optics-based approaches for numerically modeling diffraction rely on the Fast Fourier Transform (FFT) for simulating free space propagation. Despite computational efficiencies provided by the FFT, these simulations can be slow and memory-intensive due to very large array sizes needed to satisfy numerical sampling requirements imposed by the FFT algorithm. Modeling large apertures, highly aberrated or misaligned systems, or small features like primary mirror segment gaps demand even finer sampling, further degrading performance. Directly computing the discrete Fourier transform (DFT) in diffraction calculations provides greater flexibility and increased performance when compared with computing an equivalent FFT. Lentil offers generalized diffraction propagation routines using the DFT that improve simulation performance substantially, with additional optimizations for modeling segmented apertures. Lentil also implements a hybrid propagation algorithm blending physical and geometric optics to greatly improve performance in simulations where representing large tilts is required. Additionally, Lentil includes tools for modeling static and dynamic wavefront errors, radiometry, and focal plane arrays. The Lentil package and its accompanying documentation are freely available as open-source software.

The Mid-infrared ELT Imager and Spectrograph (METIS) is one of the first-light scientific instruments for the ELT with over 75 optical components. The science cases of METIS impose tight stability requirements on the optical performance. To assess whether the optical performance is harmed by micro-vibrations, the effect of numerous vibration sources on the optical stability are analyzed. We present the analysis approach and results for METIS. This includes finite element analysis to obtain transfer functions, compute rigid body motion response of optical elements and assess the optical impact by ray-tracing.

Pyxel is an opensource python-based framework to simulate images including instrumental effects with a focus on detector modelling (CCDs & EM-CCDS, CIS, Hybrid-CMOS, APDs, MKIDs etc.). Right from the start of its development at ESA, Pyxel has been conceived to easily integrate and pipeline models from different contributors and in this way foster collaboration in the instrumentation community. We give an overview of the framework focusing on the main improvements and evolution since v1.0 and examples of new features. On top of the many models that were added to the framework, the pipeline hosts now to two new model groups “scene generation” and “data processing” to make the framework even more self-consistent.

We present our numerical simulation approach for the End-to-End (E2E) model applied to various astronomical spectrographs, such as SOXS (ESO-NTT), CUBES (ESO-VLT), and ANDES (ESO-ELT), covering multiple wavelength regions. The E2E model aim at simulating the expected astronomical observations starting from the radiation of the scientific sources (or calibration sources) up to the raw-frame data produced by the detectors. The comprehensive description includes E2E architecture, computational models, and tools for rendering the simulated frames. Collaboration with Data Reduction Software (DRS) teams is discussed, along with efforts to meet instrument requirements. The contribution to the cross-correlation algorithm for the Active Flexure Compensation (AFC) system of CUBES is detailed.

HARMONI is the first light visible and near-IR integral field spectrograph for the ELT. It covers a large spectral range from 470 nm to 2450 nm with resolving powers from 3300 to 18000 and spatial sampling from 60 mas to 4 mas. It can operate in two Adaptive Optics modes - SCAO (including a High Contrast capability) and LTAO - or with NOAO. To model the optical performance we include manufacturing and alignment tolerances alongside other static and dynamic effects. Diffraction of both image and pupil become significant when the spectrograph slit width matches the diffraction limited point spread function. A set of Zemax OpticStudio macros and Python scripts are used to bring together the subsystem models that make up HARMONI and combine them to include all these effects. We present an overview of our approach to modelling this complex instrument and key results predicting the optical performance of HARMONI.

The Mid-infrared ELT Imager and Spectrograph (METIS) is one of the four first-generation scientific instruments for the Extremely Large Telescope (ELT), funded for construction by ESO and designed and built by a consortium of research institutes, lead by NOVA in the Netherlands. The consortium consists of 12 partner institutes spread over Europe and includes the US, Taiwan plus ESO. METIS is designed to operate in the 3 to 13 µm wavelength range, and aims at both imaging, spectroscopy and coronagraphy. In November 2022, METIS had its main final design review (FDR), and the METIS sub-systems are now in the manufacturing, assembly, integration and test phase (MAIT), while the preparations for the system AIT phase in Leiden has started. The management of a project of this scale comes with its own challenges. The development of METIS is a project substantially bigger than instrument developments for the Very Large Telescope (VLT), but still smaller than most space missions. In addition, also the ELT as a project differs from its predecessor VLT. With the ELT and METIS both being new facilities of a new scale it comes with its own dynamics in management, change control, and systems engineering, in which we want to make use of the state-of-the-art methods, while still utilizing the heritage built up at the partner institutes. In this paper we present the management organization of METIS, both in terms of rolled-out processes, as well as the required areas of expertise, project phasing and staffing, and compare it with previous projects. We will focus on the various lessons learned from the design phase, and the plans for the pproject phases to come.

The Advanced Instrumentation & Technology Centre (AITC) is part of the Research School of Astronomy and Astrophysics within the Australian National University and is located at Mt Stromlo in Canberra, Australia. It is the largest instrumentation research, design and development facility for astronomy and space in Australia with a track record spanning decades of expertise in those fields. The core mission of the AITC is to develop and deliver world-leading, innovative solutions for ground and space-based astronomy at visible, infrared, and ultra-violet wavelengths. AITC is also part of the Australian Instrumentation Consortium - Astralis. At the AITC, we combine our extensive knowledge and expertise in optics, mechanics, electronics, detectors, control, software, astronomy, and space technologies to design and build cutting edge instruments. We integrate robust system engineering, project management and quality assurance to deliver bespoke instruments and capabilities to our customers around the world. We leverage world-class instrumentation technologies to fields beyond astronomy such as remote sensing and laser communications. The AITC hosts the National Space Testing Facility (NTSF), a hub for space environment testing of instrument payloads and spacecrafts. We provide research services to the space community including academia, industry, and government agencies. This paper presents the operating model that the AITC has developed to manage its complex and diverse project portfolio. The model integrates the AITC’s project management, system engineering and product assurance frameworks, and combines them with the AITC quality management structure. Some examples of issues addressed over the past 4 years are presented, as well as the strengths and challenges uncovered by a recent review of the AITC operational procedures by ANU Enterprise.

The Astralis Instrumentation Consortium (Astralis) provides Australia’s national capability for optical astronomy instrumentation by combining expertise and resources from the Australian National University, Macquarie University and University of Sydney. Established in 2018 with support from Astronomy Australia Ltd. (AAL), Astralis has been in operation for over 5 years, and has been building instruments for the world’s largest telescopes. Here we present our review of the first five years of Astralis, including the benefits of building instruments in a national wide consortium environment, the challenges we have overcome, and the future of the Consortium.

Gemini Observatory conducted a technical assessment and feasibility study for the GLASS Implementation Feasibility Study 2020 project. The study aimed to improve image quality and telescope efficiency and determine cost-effectiveness. This paper outlines the project management and systems engineering framework that will be implemented to deliver complete requirements for building GLASS and integrating it into the facility. A robust systems engineering and project management foundation is crucial due to the project's technical complexity and resource constraints, as successfully implementing project monitoring and control upon actual technical progress allows for timely and informed decision-making, resulting in flexibility in the design development process.

The technologies in the eXtended Reality (XR) field have been rapidly developing in the last few years, allowing for their effective implementation in many different applications, beside the entertainment world they are more commonly associated to. This paper studies the integration of virtual and mixed reality elements in a concurrent engineering environment. More specifically, eXtended Reality tools will be employed in the Concurrent Design Facility that is being developed at the Capodimonte Astronomical Observatory in Naples, in the scope of the National Recovery and Resilience Plan project "STILES - Strengthening the Italian leadership in ELT and SKA". The XR environment will aid in the definition of the design, allowing the participants of a concurrent engineering session to inspect and manipulate complex 3D models, enabling detailed examinations of components, interfaces and potential issues. This immersive experience helps to identify design flaws and possible criticalities during various phases of the assembly, integration and operation of astronomical instrumentation, that would not be as easily found during a standard design review process. Other applications are also foreseen, including training of personnel for maintenance operations. The best way to properly integrate these tools in the design process, with the aim of effectively supporting the concurrent approach philosophy of effort and time efficiency is under study, as the Naples facility is built and tested in all its features and possibilities.

Digitally supported Systems Engineering, or Model Based Systems Engineering (MBSE) methodologies usage in full scale space science missions development in Europe is so far limited to a few cases and several factors limit a wider adoption: from lack of clear methodology, to limitations in tooling, to lack of clarity on contractual aspects. To tackle some of these limitations, a progressive implementation of MBSE practices in Science missions at the European Space Agency has been adopted, starting with the Euclid mission and continued with PLATO and ARIEL. We present an assessment of the experience in the PLATO mission with the usage of two main MBSE approaches: i) SysML model and ii) a Mission Parameters Database used for all performance and pipeline development. We review the lessons learned from the experience in Euclid, and the implementation in PLATO, and identify areas for development to reach standardization of practices in Europe.

The Thirty Meter Telescope (TMT) International Observatory (TIO) project involves complex systems engineering (SE), necessitating efficient tools for the effective management of SE processes and products. This paper explores the utilization of Atlassian Jira whose flexibility surpasses traditional methods like Excel by providing a common, collaborative database for all stakeholders, enabling concurrent updates and facilitating easy search, filter, and reporting capabilities. This paper details the incorporation of SE processes for task tracking, verification, risk management, hazard assessment, CAD issue tracking, and configuration management into Jira. Establishing traceability between related tickets fosters both small group and system-wide collaboration, and ensures that important information is not lost, forgotten, or incorrectly duplicated. Additionally, integrations with embedded apps such as SoftComply Risk Manager and an external tool ConnectALL, which syncs Jira with the IBM DOORS requirements management tool, further enhance Jira's capabilities. Customizing Jira and optimizing its features has contributed to efficient management of TIO systems engineering processes and products. Leveraging its functionalities, we have fostered a more robust and traceable design by enhancing collaboration through greater transparency and accessibility. Jira has proven to be a valuable asset in the comprehensive management of complex projects like TIO.

In this paper we will make a revision of the usage of MBSE for an astronomy-oriented instrument. We will in particular trade the benefit Versus the overhead with respect of the traditional System engineering method. We will compare different ground-based instruments for different telescope size in different project phases. We will try then to underline where MBSE have been useful and where the criticalities of this method emerged in order to draw a possible roadmap to exploit the maximum benefit achievable by this method. In detail we will focus on four main aspects. In the first part We will compare different requirement management approaches. Second, we will focus on the Interface management which is one of the most critical elements of the system engineering discipline. We will then compare the product traditional product modelling (excel based) with respect to a database oriented one. Finally, we will assess the use cases management. We will compare traditional Versus MBSE in order to allow the reader to identify which of the two approaches better fits with its needs.

Lately, the Italian astronomical community has begun the transition to Model Based System Engineering (MBSE). This tool has been largely applied to the development of the Cassegrain U-Band Efficient Spectrograph (CUBES) designed to provide high instrumental efficiency ( > 37 %) observations in the near UV (305-400 nm requirement, 300-420 nm goal) at a spectral resolving power of R > 20, 000 (with a lower-resolution, skylimited mode of R ≈ 7, 000). Here, MBSE has been used mainly in 3 areas: requirements management, activities modeling, and generation of system structure documents, like the Product Breakdown Structure (PBS) or the Bill of Materials (BoM). Requirements management controls the flow-down process to have a coherent list of requirements. This is achieved using derived properties and tailored numbering. Activities modeling uses traditional MBSE techniques while mimicking the software templates for calibration and observation. To generate structural documents, the system structure is generated in Cameo using the outputs from the subsystems, granting high coherency between the model and the actual design state. The interaction with non-Cameo users relies on Excel files, accessible to all interested parties and usable by Cameo to export and import information.

The Ariel space mission will characterize spectroscopically the atmospheres of a large and diverse sample of hundreds of exoplanets.. Ariel is an ESA Medium class science mission (M4) with a spacecraft bus developed by industry under contract to ESA, and a Payload provided by a consortium of national funding agencies in ESA member states, plus contributions from NASA, the CSA and JAXA. With the payload being provided by a consortium of scientific institutes and industrial partners funded through their respective European national funding agencies, and additional contributions provided by ESA, NASA, CSA and JAXA, the coordination and management of this team is vital to the successful delivery of the mission. This paper will describe how we have tailored the standard systems engineering approaches taken for space instrumentation and implemented these in the large consortium structure. This has been done in order to try to maximise the efficiency of the consortium work and to allow as close to a seamless flow of information as possible. We outline the key tools being deployed by the payload management, systems engineering and product assurance teams in the consortium.

The ELT construction programme some months ago passed the 50% completion in terms of earned value. In the last couple of years, the detailed design phase of the ELT was finalised and many subsystems are already under construction (some close to be delivered to ESO). As part of the final design consolidation, there was still room for optimizing the diffractionlimited performance of the telescope. A significant effort has been devoted to investigating potential areas of improvement in the as-designed ELT system. The most prominent cases are local-seeing reduction, pupil fragmentation mitigation and vibration rejection. Although the work in these areas started years ago when stating requirements on the concerned subsystems to arrive to the as-specified telescope, in the last two years we have been able to run system-level simulations with the as designed subsystems providing unvaluable feedback for optimizing the ELT performance. This paper presents the several system-level activities that have been undertaken and describes the objectives, the work done, as well as the results that have been obtained so far.

The ELT Phasing and Diagnostic Station (PDS), is a multi-purpose optomechanical system providing metrology tools to phase the segmented primary mirror of the ELT and hosting the sensors required to verify AO-assisted diffraction limited image quality at the ELT. The purpose of the PDS in the context of the ELT lifecycle is twofold. On one side, during the AIV phase of the ELT, the PDS will be the fundamental tool enabling commissioning of the telescope. On the other hand, during operation, the PDS will provide the essential metrology means to monitor performance and detect and isolate potential failures within the observatory. The project, which is one of the most important internal development endeavors at ESO, passed PDR in mid-2021 and underwent an optical final design review in late 2021, where challenges associated to the schedule were identified and more time was given to optimize the design. The project underwent a restructuring in early 2022 before starting its final design phase which has been successfully completed in 2023. In the same period all procurements concerning critical long lead items have been launched. The present contribution first introduces the project in the context of the ELT construction programme, outlining the project structure and the project management tools employed for planning and progress monitoring. Subsequently, the main system engineering processes used within the project will be described. Finally, we report on the main technical results obtained during the final design phase and the plans for the assembly, integration and test of the system.

ANDES (ArmazoNes high Dispersion Echelle Spectrograph) is one of the second-phase instruments planned for the Extremely Large Telescope (ELT) of ESO. ANDES will provide high-resolution spectroscopy in the visible and near-infrared wavelengths, enabling a wide range of scientific investigations, such as characterizing exoplanet atmospheres, testing fundamental physics, and measuring the cosmic expansion. In this paper, we present the general strategy of the Model-Based Systems Engineering (MBSE) approach that we have used to design the instrument during the Phase B-One, which covers the system architecture review (SAR) successfully completed at end 2023. We describe how we have applied the Cameo Systems Modeler tool to create and manage the system model in compliance with the SysML standard to perform requirements and interfaces management, structure verification and validation, and trade-off analysis. We also emphasize that ANDES is used as a test case for the application of the MBSE methodology in the astronomical field, in order to create a standard of procedures to perform all the actions and tasks that serve to satisfy all the steps in the various design phases of an ESO project. In fact, the initial phases require specific tasks, such as the analysis of requirements, the flow-down of specifications to the subsystems, the tracing of interfaces, the analysis of budgets. Since there is no tool that specifically encompasses all these capabilities in the astronomical field, it is necessary to define a robust methodology that can be taken as an example for future astronomical instrumentation. We discuss the benefits and challenges of using MBSE for ANDES, as well as the lessons learned and best practices that can be useful for other astronomical instrument projects.

Within the ESA PLATO M3 mission, the Telescope Optical Unit (TOU), i.e. the opto-mechanical unit, is a fully refractive optical system. The 26 TOU Flight Models (FM) to be delivered to the upper level, the PLATO Camera, make it a series production. The first Flight Models production faced many initial challenges from a Product Assurance point of view, mostly related to MAIT activities, while moving forward these challenges decreased. Discrepancies and nonconformities associated with, mainly, but not only, materials and processes, cleanliness and contamination control, safety, qualifications and validations, are the object of this proceeding. Thus, showing that serial production adds one more variable to possible failures, but at the same time, when root causes are corrected and solved, yields less difficulties in subsequent FMs MAIT and final production. Product Assurance, in monitoring the product in failure-proofing aspects, aims at mitigating criticalities and arranging for corrective and preventive actions that allow improving the likelihood of success of the mission.

The Vera C. Rubin Observatory is one of the first observatories to apply Model-Based Systems Engineering in all major aspects of the project. This paper describes the evolution of the processes, methodologies and tools developed and utilized by the Rubin Observatory Team. It specifically focuses on the Rubin Systems Engineering Processes for Image Quality tracking, Computerized Maintenance Management System (CMMS) selection, Failure Reporting, Analysis, Corrective Action System (FRACAS) handling, and Hazard Mitigation Analysis. Here, we share updates on each topic’s workflows, experiences, and difficulties with the community.

For the ELT, a total of 931 M1 Segment Assemblies will be manufactured. These will be of 133 different types, 7 copies each, with different optical and mechanical properties. The manufacturing of the segment support, the glass blank and the polishing will be done by industrial partners. ESO will be responsible for the shipment of the Segment Assemblies to Chile, for the integration of the edge sensors and their electronics, and for the cleaning and coating. After performing several health- and quality-checks, the Segment Assemblies will be temporarily stored in the warehouse, before being installed at the telescope and eventually recoated around every 2 years. The telescopes and instruments for optical astronomy are usually prototypes, while a new approach is required to manage such a series production of crucial components, which differ in small but significant aspects. In this paper, we will present the processes we have developed to manage the series production of M1 Segment Assemblies for the ELT, starting from the reception of the Segment Assemblies in Chile, inspection, installation of sub-components, health-checks, storage, and installation at the telescope.

Controlling work processes and inventories at the Thirty Meter Telescope (TMT) International Observatory (TIO) is an important function due to the interactivity of subsystems and various teams, and to ensure there is minimal impact to nighttime operations due to failures of any kind. In addition, there is precision and conformity required when working with optics and other complex systems at the high altitude of Mauna Kea. Whilst telescopes such as the TIO are complex machines, tools used to control assets and maintenance activities should not be. The purpose of such a tool should be to guarantee successful outcomes via efficient inputs. In this paper we share our method for determining the criteria and tool selection for TIO’s management of assets, inventory, and maintenance activities. Our proposed method integrates technical, functional, and organizational elements that factored into the criteria weightings. Technical specifications evaluate compatibility, customization and scalability. Functional criteria assess workflows, scheduling, inventory control, and reporting. Organizational criteria evaluate vendor support, product documentation, and long-term viability. The application of a weighted score system enables quantitative comparison between each possibility 1, ensuring the selected tool meets the needs of TIO, thus maximizing the benefits provided by an effective maintenance management tool.

MOSAIC is an instrument for the Extremely Large Telescope (ELT). The instrument has started phase B, and apart from technical and financial requirements, MOSAIC has the additional requirement to investigate and minimise its environmental impact. The first step is to estimate the carbon footprint (and other effects) in a ‘Life Cycle Analysis’, for the instrument development up to Provisional Acceptance in Chile. This paper presents a preliminary analysis, aimed at identifying potential contributors to environmental impact. Investigated contributors are: materials, Full-Time-Equivalents, travel, and transport of the instrument. Not yet investigated (due to lack of information or certainty) are: electronics, test facilities and prototyping. Uncertainty in input data and conversion factors leads to error bars of a factor 2 or larger. Therefore, the outcome of the analysis can be used for internal comparison of contributors only, and it should not be used for comparison to other instruments or disciplines.

Leighton Chajnantor Telescope (LCT) will be moved to the new site at Chajnantor Plateau, Chile in 2024. The new site has high wind speed and large temperature difference, which leads to strong wind disturbance and beam offset for LCT due to the deformation of the primary reflector. To achieve a high pointing control accuracy, we propose a composite feedforward/feedback control policy (CFFCP), which integrates disturbance observer-based feedforward control policy (DOB-FFCP) and the robust feedback control policy (RFBCP) to compensate the wind disturbance and the beam offset compensation strategy (BOCS) to reduce the negative effect caused by the beam offset respectively. The results of simulation on the synthesized model of LCT’s pointing control system reveal that the proposed CFFCP can signific antly reduce the pointing error during the observations.

The Giant Magellan Telescope Project relies heavily on integrated modeling (IM) to validate various high-level performance requirements and operating conditions of its subsystems. The deformable nature of optics and structures play a central role in these efforts, and finite-element methods are the natural choice to approximate this behavior. The integrated modeling group at GMTO maintains a detailed FE model (mesh) of the entire telescope from foundation to top-end. Representations derived from this model are a very important component of simulations studying the effects of vibrations and misalignments due to wind, gravity, temperature variations, drives, actuators, utilities, and instruments on the image formation process. This paper introduces strategies and methods specifically tailored to the unique requirements and constraints of the project, surrounding this FEM for systems engineering purposes at GMTO. This covers two closely related topics of which the second is the main focus of this paper: First, the mesh assembly, maintenance and verification processes that build upon sub-system FE modeling efforts to minimize the resources required to keep the model up-to-date with the state of the design and provide variants for trade studies. The second topic is the model abstraction process that generates static and dynamic (modal) representations of the model, primarily used in integrated time-domain simulations that also incorporate controls, optical computations and environmental inputs. The strategies and methods for this second part must take into account, among other factors, the very large size of the FE mesh, the requirements for long duration time-domain simulations with very small time steps, the very large number of inputs and outputs needed to accurately capture active and adaptive optics, the continuous evolution of designs and interfaces, verification practices, and advances in cloud computing.

Self-induced vibrations along with wind-induced jitter are considered as most limiting factors for the performance of the Giant Magellan Telescope (GMT). The status of dynamic analysis in context of the latest GMT mount design activities is reported. Particular attention is paid to the vibration error budget, which is used to manage active disturbances to meet demanding tracking performance requirements. The vibration budget is based on tracking simulation results combined with contributions from different jitter and vibration sources such as drives, utility wraps, cabinets, and many other subsystems. The Mount Transfer Function (MTF) concept as an important tool for analysis of vibration paths from the source to the image motion is introduced and its application in several use cases with both modeled and measured disturbances is illustrated.

MICADO is a cryogenic near infrared Multi-AO Imaging Camera and Spectrometer developed for the first light operations at the ELT. It will operate in a “Standalone” configuration with a Single Conjugate Adaptive Optics module for a nominal period of two years. After this time, the system will be re-arranged in the “MICADO-MORFEO” configuration, being able to switch between the SCAO and a Multi Conjugate Adaptive Optics module in the later phase of the project. The lifetime requirement of minimum ten years, together with other demanding requisites about its availability and reliability triggered a meticulous FMECA analysis mainly focused on developing robust maintenance strategies. In this paper, we outline the assumptions and the boundaries of the MICADO RAM analysis, a collaborative effort involving the Max Planck Institute for the Extraterrestrial Physics, the Laboratoir d’Études Spatiales et d’Instrumentation en Astrophysique and the European Southern Observatory, starting from the input provided by all MICADO partners. We describe how RAM aspects drove some design choices as well as the selection and use of components. We report the preventive and predictive maintenance strategies, which we considered to minimize the risk of instrument downtime in the high cost operational context of the ELT.

The field of Reliability, Availability, Maintainability, and Safety (RAMS) analysis traditionally adheres to principles established mainly for space-based systems. However, in the pursuit of optimizing RAMS for our specific system, Phasing and Diagnostic Station (PDS), developed for ESO-ELT, it has become imperative to introduce deliberate deviations from these conventions. This presentation aims to elucidate the practicality and underlying rationale for these strategic deviations, shedding light on the advantageous outcomes they yield for our system's performance. The primary focus will be on redefining RAMS requirements tailored to our system's unique characteristics and operational challenges. We intend to engage in a constructive dialogue with the audience, emphasizing the importance of optimizing these requirements to align seamlessly with the distinctive needs of our system. Furthermore, we will delve into the critical aspect of obsolescence planning, which directly stems from the concepts of availability and maintainability within RAMS. This planning is crucial for ensuring our system's longevity and continued operational excellence.

PLATO (PLAnetary Transits and Oscillations of stars) is an M3 medium-class space mission in ESA’s Cosmic Vision program devoted to detecting and studying a large number of extrasolar planetary systems. Its launch is planned for the end of 2026 from Europe’s Spaceport in French Guiana. The PLATO Payload consists of 26 wide field-of-view Cameras, each observing a specific part of the sky, associated data processing units and power supply units. The 24 Normal-Cameras will provide a very high-resolution photometric measurement of light from a large number of stars, while the other two Fast Cameras will provide the colour information and will deliver the pointing data to the AOCS (Attitude and Orbital Control System). The Cameras will be integrated into an optical bench. Each of them is composed of the Telescope Optical Unit (TOU), the Focal Plane Assembly (FPA) and the Front-End Electronics (FEE). Currently, the serial production of the Cameras has already started facing critical key points, non-conformities and challenging problems. The status of the Product Assurance activities during the serial production for which the first flight models are being delivered after the AIT phase is reported.

Complexity and operations costs are almost part of the game in the design of a modern instrument for ground-based telescopes. MORFEO (Multi-conjugate adaptive Optics Relay For ELT Observations), formerly known as MAORY is the first light MCAO instrument for the ELT and its design has been driven also from the Reliability, Availability, and Maintainability point of view since its early phases. Now entering the Final Design Review, particular attention has been considered in evaluation resources for preventive and corrective maintenance to reach the high level of availability requested by ELT requirements. After a general view of the philosophy adopted for the RAM analysis of MORFEO, the case of the Low Order sensor subsystem is proposed to show how requirements flow-down can be proactively used to ensure that the low-level characteristics, such as LRU accessibility, spare parts identification, and straightforwardness of maintenance operations can be addressed since the design phase.

The National Science Foundation’s (NSF) Daniel K. Inouye Solar Telescope (DKIST) is a four-meter off-axis telescope on the island of Maui, Hawai'i. DKIST took its first light images in 2019, making it the most powerful solar telescope in the world. From the inception of DKIST, safety was a fundamental consideration. To ensure that hazard reduction was considered throughout a Hazard Analysis Team (HAT) was formed from members of the staff. This team conducted regular meetings during the design phases to analyze design choices, assess inter-system hazards, and to ensure compliance with safety standards. In addition to the core team members, subject matter experts were brought into the meetings when specific expertise was needed. A key understanding was that hazard analysis (HA) was not a single event or deliverable, but a continuous, managed process to ensure that hazards were properly identified, analyzed, and mitigated. As the design matured, the HAT continued meetings, retiring some hazards, while identifying new hazards. New hazards would appear not only because of changes in the design but also from a better understanding of the interaction between observatory systems. The DKIST is now beyond the construction phase and moving into operations yet we find that the HAT continues to be used to refine how hazards are handled and implement mitigations appropriately. Changes to the hazard analysis process itself were also implemented as we learned how to better handle our hazard analysis procedures. During the early design and construction phases, hazard analyses were a required contract deliverable, with the HAs conducted by individual sub-system vendors. As the project shifted from design into construction and eventually integration, the various hazard analyses had to be combined. New tools for tracking hazards and methods for on-line collaboration were added to aid continuing management of hazards as the project shifted from design to construction to operations.

The NRC integrated modelling (NRCim) toolset has been developed at the NRC Herzberg Astronomy and Astrophysics Research Centre (HAA) for many years and has been used to predict complex system performance for several projects (eg. TMT primary mirror, NFIRAOS, IRIS, GPI). Although extensive software validation has been completed to ensure the validity of the NRCim results, there has not previously been an opportunity to measure the delivered performance of an instrument and complete an experimental validation of the NRCim toolset. With the recent assembly and testing of the SPIDERS instrument (Subaru Pathfinder Instrument for Detecting Exoplanets & Retrieving Spectra), our team at HAA has used the NRCim toolset to predict the performance of the SPIDERS instrument and subsequently completed directly measurements of the performance in the presence of prescribed disturbances. The measurements of the SPIDERS performance are compared with the NRCim-predicted performance providing a direct validation of the NRCim toolset.

This study focuses on optimizing the thermal performance of the Visible Extragalactic background RadiaTion Exploration by CubeSat (VERTECS), a 6U CubeSat with a 3U telescope for observing Extragalactic Background Light. Aside from dealing with satellite survivability in the space environment, the payload includes a CMOS sensor which requires operational temperatures of less than 0°C to minimize the noise due to temperature dependent dark current in observation data. The payload telescope lens optical system is designed to operate within a temperature range of -10°C to 35°C. The thermal analysis considers solar radiation, internal heat dissipation, and external factors in various orbital scenarios. The investigation identifies potential temperature fluctuations and proposes passive thermal control strategies, including enhanced coatings and radiators. By implementing tailored strategies, this research enhances the reliability and longevity of 6U CubeSat missions, advancing small satellite technology in space exploration and scientific research.

The Nancy Grace Roman Telescope (RST) is a NASA observatory designed to unravel the secrets of dark energy and dark matter, search for and image exoplanets, and explore many topics in infrared optics. Scheduled to launch in no earlier than October 2026, this 2.4 meter aperture telescope has a field of view 100 times greater than the Hubble Space Telescope. The mission is currently in its construction phase, where integrated modeling between thermal, structural, and optical models of the observatory is necessary to demonstrate science quality images over the range of operational parameters. This presentation discusses the most recent integrated modeling analysis cycle for Roman, including model correlation with our instrument level testing. We include a discussion on improved processes of the handling of the various flows of data between the modeling disciplines and discipline specific monte-carlo analysis predictions. We will finish with the predicted uncertainties and expected performance for our upcoming observatory alignment verification test using machine learning algorithms.

Stray light (SL) control is an important aspect in the development of optical instruments. Iterations are necessary between design and analysis phases, where ray tracing simulations are performed for performance prediction. This process involves trial and error, requiring to be able to perform rapid evaluation of SL properties. The limitation is that accurate SL simulations require sending many rays, which can be time consuming. In this paper, we use deep learning to improve the accuracy of SL maps even when obtained with very few rays. Two different deep learning methods are used. The training process is performed by generating a large database of artificial SL maps, with different noise levels reproduced with a Poisson distribution. Once the training completed, we show that the autoencoder performs the best and improves significantly the accuracy of SL maps. Even with extremely small number of rays, it recovers complex SL patterns which are not visible on raw ray traced maps. This method thus enables more efficient iterations between design and analysis. It is also useful for developing SL correction algorithms, as it requires tracing SL maps under large number of illumination conditions in a reasonable amount of time

The Giant Magellan Telescope Project relies on a comprehensive integrated modeling (IM) tool to evaluate Observatory Performance Modes (OPM), ranging from Seeing Limited to Adaptive Optics. The development of the integrated model is driven by the need to accurately estimate errors that affect the science instrument data products and mitigate technological risks associated with the telescope. The IM end-to-end simulation models combine structural dynamics, optics, and control models seamlessly in a unified framework. Computational fluid dynamics analysis produces a set of time series representing most of the disturbance sources affecting the telescope performance (namely, dome seeing, wind loads, and structural thermal deformations) under different boundary conditions. Conceiving and managing such a tool imposes several challenges. Firstly, due to the wide range of scientific and engineering expertise required. Furthermore, developing a realistic system representation while dealing with the computational aspects is critical, particularly in adaptive optics OPMs, where the system complexity (vast number of degrees of freedom combining slow and fast dynamic behaviors demanding high sampling rates) can make simulations impractically long. This paper presents the architecture of the GMT integrated model tailored for the Natural Guide Star and Laser Tomography Adaptive Optics OPMs. The features of the computing framework that integrates the domain-specific models into a unified model are also approached. We also show end-to-end simulation results illustrating the interaction between the control loops composing those adaptive optics modes.

We present the experiences acquired in the last decade by analyzing and evaluating the impact of more than 800 technology grants for technology developments awarded by the Astrophysics Division at NASA Headquarters. These studies have demonstrated a healthy infusion rate of these funded technologies and provided insights into the lifecycle of technology development components, and systems, which remain over a decade and in some cases up to two decades.

The Canadian Hydrogen Observatory for Radio-transient Detectors (CHORD) will consist of 640 six-meter diameter antennas made of fiberglass composite material. The antennas will be fabricated and assembled at the Dominion Radio Astrophysical Observatory (DRAO) in Kaleden, BC, Canada, managed by the National Research Council of Canada (NRC). NRC has developed composite based single piece reflector technology over the past decade. A high degree of dimensional repeatability is key for CHORD to meet its scientific goals. This begins by manufacturing highly stable and repeatable dish molds. Subsequently, highly repeatable dishes are manufactured, components are assembled, and antennas are precisely positioned in the CHORD array. In this paper we present the antenna mechanical system, production of the antenna, top-level requirements, error definitions and verification plan, performance verification plan, and quality management plan. Since the antennas are made of composites, formulating an error budget is critical to keep track of the error allocations due to process induced errors, tooling and mold errors, and surface distortions due to gravity, wind and temperature variation. In addition, an overall pointing budget has been prepared to allocate the effect of mechanical misalignment, wind, foundation movement and other sources, etc. A Monte Carlo simulation of 1000 antennas provided the error stack up and expected precision values. A detailed verification plan is presented. Finally, the quality engineering plans are in place so that the manufacturing facility can ensure the production of the repeatable antennas through a quality assurance program. An acceptance sampling of the antennas will be conducted for metrology-based verification. A robust quality management plan is also in place to safeguard repeatability of the antenna production. The antennas will be accompanied by production data-cards, which enlist the critical configuration and process data about the antenna production and assembly operations. At the end of the pipeline, these antennas will go through verifications and acceptance tests to validate that performance requirements are met.

ASTRON, the Netherlands Institute for Radio Astronomy, oversees the full lifecycle of radio astronomy instrumentation from design and construction to operations and maintenance. In some cases, ASTRON realises entirely new instruments such as the Westerbork Synthesis Radio Telescope or the LOw Frequency ARray, LOFAR, in others it drives innovative modifications to existing infrastructure such as APERTIF and the various LOFAR upgrades. While the high scientific quality of the instrumentation delivered remains top priority, completing projects within budget and on time have become increasingly important success factors over the years. Navigating this complex playing field not only requires engineering and technical excellence but also strong support from the disciplines of project management and systems engineering. In recent years, ASTRON has embarked on a journey to further professionalise its instrument development process. Daring to experiment with novel approaches, learning from them and implementing the lessons learnt in practice play a pivotal role herein. By now, these efforts have led to a wide range of improvements, including the introduction of practical systems engineering methods with a preference for modelling over documentation, an iterative approach to development building upon a minimum viable product and increasingly complex prototypes, an agile approach to planning and teamwork, close involvement of stakeholders in the development process and continuous professional development of the systems engineers and project managers. These improvements have now translated into a more professional way of project execution, better teamwork, increased stakeholder satisfaction and more transparency in project progress and costs.

We present a trade study on design changes to the Wide Field Optical Spectrometer for the Thirty Meter Telescope. WFOS is planned as a first light instrument providing imaging and multi-slit spectroscopy over the wavelength range 0.31 to 1µm across a field of view of 8.3 by 3 arcminutes. The baseline prior to the trade study used laser cut metal slit masks at the focal plane to enable observation of ~50 to 80 objects simultaneously. The configurable slit unit design uses multiple knife edges mounted on computer-controlled bars to create up to 88 reconfigurable slits, enabling the ability to adapt to seeing conditions or to respond to targets of opportunity. We detail here the decision criteria, and science case analysis used by the WFOS team to decide to change the baseline design of WFOS to incorporate a CSU.

Decisions made early in a mission design, when information is sparse, define most of the downstream development cost. This becomes particularly problematic when uncertainties will not be revealed until later in the design life cycle. A resilient architecture is one that is adaptable to uncertainty, permitting cost-effective architectural changes as uncertainties reveal themselves. A framework is proposed for designing a resilient architecture for NASA’s Habitable Worlds Observatory (HWO). Uncertainties include knowledge of exo-Earth targets prior to launch, needed spectral bands to mitigate ambiguity in habitability, and performance limits of starlight suppression technologies. Precursor science and technology advancements drive architecture definition more than the converse. In essence, it is better to plan for, then react to, uncertainty.

The construction of the ELT is now in full swing. This is true both for the construction of the Dome and Main Structure (DMS) in Chile, but also for all the other sub-systems manufactured by industrial partners in Europe. While the DMS is entirely managed by the industrial consortium, the shipment to Chile and the installation at the telescope of the other subsystems is mostly under the responsibility of ESO. The shipment of these components from Europe to Chile has started recently and will soon reach a level of ~10'000 components/month. All these components will need to be tracked during their shipment, incoming inspections will need to be performed, health-checks and integration with other components will need to be done. The components will then be stored temporarily at the warehouse, before being installed at the telescope. We will present the approach for the logistics, infrastructure, and the tools set up to manage the status and location of all these components and to keep the link to their associated latest documentation.

The manufacturing and assembly of the CTAO Medium-Sized Telescopes (MST) is a complex process that involves a geographically dispersed engineering collaboration. This collaboration must integrate all stakeholders, provide effective decision-making procedures, and establish reliable and efficient material and information flow. One of the key challenges in mastering this process is the digitalisation of manufacturing planning, coordination and progress tracking processes based on a Product Lifecycle Management (PLM) system. The PLM system provides comprehensive engineering data and digital workflow for activities such as reviews and sign-offs, as well as for managing changes and non-conformities. The digitalisation of the manufacturing process enables the optimisation of logistics and the automation of workflow. It facilitates the creation of shared vision among all involved parties and ensures the prompt and effective implementation of decisions. This paper presents an overview of the current status of the MST project and the implementation of the PLM system.

The ALMA observatory in Chile is an interferometer consisting of 66 antennas that act together as a single telescope. Each antenna hosts a set of 10 receivers working in different frequency bands. The repetitive nature of ALMA demands a “serial” approach towards the development and production of its receivers. Series of up to 70 (66 and spares) high quality and reliable receivers are required, which can only be achieved when a special work attitude is adopted. All starts with a good design, considering that the receivers must be built in small series. Parts are ordered in industry, the design must be simple, structural wise, with as little as possible different parts. The receivers must be easy to build, accessible with dedicated tools and best is if assembly is possible with a single engineer only. In the ordering process contact on a regular basis is vital, not all information is transferable in drawings and documents. Working with wellknown companies is preferable. Inspection of components and parts needs the highest priority: for the assembly phase no checking or rework shall be needed. The engineer must be confident that all is perfect, just to be able to focus on the assembly only. Part of the inspection is the electronic and RF testing of different components. This beholds implementation of a good documenting system for these inspections: to be able to have close and fruitful contacts with the manufacturers, inspection reports are invaluable for a feedback loop to optimize the production of parts. Also, lessons learned in these documents from former projects shall be studied in advance of the start of the inspection or even the design phase. Conclusion is that to make reliable instruments in a repeatable way, hyperfocus is needed at the assembly process: the consequence is that all components on the workbench need to be in perfect condition; Product and Quality Assurance is the heart of this process.

The Enhanced X-ray Timing and Polarimetry (eXTP) mission is a flagship astronomy mission led by the Chinese Academy of Sciences (CAS) and scheduled for launch in 2029. The Large Area Detector (LAD) is one of the instruments on board eXTP and is dedicated to studying the timing of X-ray sources with unprecedented sensitivity. The development of the eXTP LAD involves a significant mass production of elements to be deployed in a significant number of countries (Italy, Austria, Germany, Poland, China, Czech Republic, France). This feature makes the Manufacturing, Assembly, Integration and Test (MAIT), Verification and Calibration the most challenging and critical tasks of the project. An optimized Flight Model (FM) implementation plan has been drawn up, aiming at a production rate of 2 Modules per week. This plan is based on the interleaving of a series of parallel elementary activities in order to make the most efficient use of time and resources and to ensure that the schedule is met.

The Gemini Infra-Red Multi-Object Spectrograph (GIRMOS) is a high-resolution integral-field spectroscope and imager being built by a consortium of Canadian universities and institutions, along with the International Gemini Observatory (Gemini) and the Korea Astronomy and Space Science Institute (KASI). The team needed a cost-effective way to bring a degree in Product and Quality Assurance to bear on instrument development, but without availability of a dedicated team. Advice and support from the Thirty Meter Telescope (TMT) Systems Engineering Team enabled GIRMOS to tailor and scale the TMT approach to fit within the available resources of a much smaller project. This Failure Modes and Effects Analysis (FMEA) method more easily allowed geographically distributed subsystem teams to work independently within an agreed-upon FMEA framework that rolled up into a System-level analysis. The TMT FMEA framework reduced the effort involved in all the follow-on work that used the same data set, namely sparing analysis, reliability and uptime analyses, and accelerated life testing.

The road to increasingly more challenging and bigger systems in astronomy is resulting in as much bigger challenges to the safety for people and things. As well for the ELT (Extremely Large Telescope) instrumentation and modules, these big “systems” collaborate and share the same environment and spaces, and, as for the AO module MORFEO (Multi-conjugate adaptive Optics Relay For ELT Observations) and the MICADO camera (Multi-AO Imaging Camera for Deep Observations), some subsystems are strongly embedded, even if they are designed by different consortia. Therefore, the designers are thinking to even more sophisticated systems to assure the safety and communication of information between the different instruments. In this context, the MORFEO consortium is investigating on the possibility to use industrial safety modules, architecturally integrated in the overall control system. This approach can highly help in the fulfilling of even more complex requirements with the high flexibility required to grant the possibility, during the telescope life, of one or more upgrading of the instrumentation and their way to co-operate. The paper goes through a comparison between the in-house designed safety solution, widely used in the past, and the industrial safety systems and the implementation of these technologies in the ground-based astronomy.

Over the years, the European Southern Observatory (ESO) and a collaborative network of national agencies, institutes, and universities have continually upgraded the VLT and its array of telescopes, accompanied by various cutting-edge instruments and modules. Among the next generation of instruments, there is CUBES (Cassegrain U-Band Efficient Spectrograph), a mid-resolution spectrograph working in the UV ground-based band (300-400 nm). The work presented here is a proceeding on the CUBES hardware dependability and maintainability analysis up to the successful Preliminary Design Review (passed in December 2022) and some forthcoming updates from the ongoing Final Design phase. The work has been developed during the design phases in order to assess the dependability of the System, as part of the Very Large Telescope, and to verify the compliance with the System requirements. The goal has been the identification of the criticalities and potential failure and the definition of the basics of maintainability in view of the last phases of the project, with the aim to keep the system in operation with high availability. Furthermore, the document provides the functional analysis of the System, with a deep focus on the influence of the “degraded modes” on the reliability of the System. Reliability analysis plays a crucial role in ensuring the components of the CUBES project meet stringent performance expectations. It assesses the likelihood of component failure, providing insights into potential vulnerabilities and enabling proactive problem-solving to enhance overall system reliability.

RAM analysis is crucial for the success of any measurement campaign and must be implemented at the earliest design phase of building an astronomical instrument. ANDES (ArmazoNes high Dispersion Echelle Spectrograph) currently in phase B will be the high-resolution spectrograph for the ELT formerly known as ELT-HIRES. Its design in the extended version foresees four spectrographs fed by fibers and operating both in seeing and diffraction-limited (adaptive optics assisted) mode. Due to these properties strictly related to flexibility and modularity, a RAM approach focused on different scientific data requirements permits a high availability for the main data acquisition modes. To implement this process, the product tree, active elements, modularity, component duty cycles, and degraded modes were defined in the earlier phases. In this way, RAM requirements contribute to defining design. This process avoids missing the control of particular aspects like maintenance accessibility, cost of operations, and downtime due to maintenance. The paper presents the process and how it is implemented in the ANDES project, thereby suggesting a design solution for the instrument.

MAVIS is an instrument being built for the ESO’s VLT AOF (Adaptive Optics Facility on UT4 Yepun). MAVIS stands for MCAO Assisted Visible Imager and Spectrograph. It is intended to be installed at the Nasmyth focus of the VLT UT4 and is made of two main parts: an Adaptive Optics (AO) system that cancels the image blurring induced by atmospheric turbulence and its post focal instrumentation, an imager and an IFU spectrograph, both covering the visible part of the light spectrum. The MAVIS project has completed PDR and is currently in the final design stage of development. We present the integrated framework, and the software tool developed the reliability, availability, maintainability, and hazards analysis, examples of RAMS analysis and the impact on the design and development of MAVIS. Additionally, we present how the RAMS framework integrates with MAVIS model-based system engineering and project management frameworks and tools.

Safety analysis methodically assesses potential hazards and risks associated with a system. It encompasses an evaluation of all potential sources of harm, including equipment failures, human errors, and external factors, aiming to identify vulnerabilities and devise risk mitigation strategies. This proceeding presents the safety analysis technique and results for the Cassegrain U-Band Efficient Spectrograph (CUBES), Very Large Telescope (VLT) class Instrument, with a specific focus on its safety aspects. This analysis presents the assessment of the Severity, Probability, and Risk factors that each hazard has on humans, damage to products, or the loss of operations. CUBES, as a complex instrument, falls into multiple hazard classes, each with unique risks. Thus, this safety analysis plays a crucial role in ensuring the project’s safe operation. The methodology used follows five steps in Assessing and Mitigating the risk. Obtained results give an insight into the effectiveness of the carried out mitigation, reducing the unacceptable hazards from twenty-one to zero.

The Submillimeter array (SMA) is an array of 8 antennas operating at millimeter and sub-millimeter frequencies on Maunakea, Hawaii. At present, the frequency coverage of the SMA is from 180 to 420 GHz. Here we describe the challenges and progress of the SMA in implementing the wideband upgrade: the wSMA project, that we are undertaking. The existing or legacy instrument at the SMA consists of 4 single polarization Double-Side-Band (DSB) receivers. They are housed in a single cryostat with an aging He-4 GM/JT cryocooler. At the heart of the wSMA upgrade is a new receiver cryostat, cooled by a Cryomech PT410-RM pulse tube. The cryostat houses two dual-polarized receiver cartridges equipped with DSB SIS mixers. New Local Oscillator (LO) subsystems, based on a Voltage-Controlled Oscillator (VCO), as well as new mixer control electronics and IF processing upgrades are being introduced. Since there are differences between the existing SMA instrumentation and the new wSMA receiver system, in terms of sky frequency coverage and the available modes of operation, there are significant challenges of operating the legacy systems and the new wSMA instruments in parallel during the transition period. As it will take several years to replace the instrumentation in all 8 antennas, a detailed plan has been laid out to integrate the new instrument hardware and software packages into the array. We will present the transition plan to full wSMA operation, and we will also describe the antenna infrastructure changes, focusing on repurposing existing equipment and optics. In this presentation we will also discuss the comprehensive installation plan, in which the new wSMA cryostat, together with its associated compressor, chiller, electronics, LO's, cartridges, vacuum system are to be installed into the existing receiver cabin space. Another aspect of the project is to upgrade the internal computer networking that will be a key element of the upgrade, allowing the access and control of the distributed microcontrollers used in the entire instrumentation. The wSMA upgrade is expected to enhance the SMA's capabilities, further improve its sensitivity, as well as widening the Intermediate Frequency (IF) bandwidth. The transition plan that we have drawn up ensures that the wSMA upgrade will be easy to operate and will reduce the maintenance requirements by the SMA technical staff.

The Telescopio Nazionale Galileo (TNG), located on the island of La Palma, has undergone a series of technological upgrades since its first light in 1998. The main challenge has been to improve its electronic control systems without compromising nighttime observations. This study presents an effective methodology for updating systems while maintaining the operational functionality of the telescope. The developed methodology allows for optimal scheduling of tests without interfering with crucial nighttime observations, organizing them during less critical periods and on nights designated for testing or maintenance, ensuring uninterrupted observation schedules.

NFIRAOS (Narrow-Field InfraRed Adaptive Optics System) will be the first-light multi-conjugate adaptive optics system for the Thirty Meter Telescope (TMT). The system will be built, tested, and integrated with the first instrument, IRIS (InfraRed Imaging Spectrograph), at Herzberg Astronomy and Astrophysics (HAA) in Victoria BC. NFIRAOS is a complex instrument that will require careful integration planning to meet cost, schedule and performance deliverables. HAA has purpose-built a new facility for the integration of NFIRAOS. We present the key features of this building, and their roles during the assembly, integration, and test phase (AIV). NFIRAOS and IRIS will be fully operational in Victoria, including providing calibration sources, and able to close the adaptive optics (AO) loops with the IRIS On-Instrument Wavefront sensors. NFIRAOS will then be disassembled and shipped to TMT for final construction and commissioning, which requires navigating some logistical challenges.

SOXS (SOn of X-Shooter) is a high-efficiency spectrograph with a mean Resolution-Slit product of about 3500 over the entire band capable of simultaneously observing the complete spectral range 350-2000 nm. It consists of three scientific arms (the UV-VIS Spectrograph, the NIR Spectrograph, and the Acquisition Camera) connected by the Common Path system to the NTT, and the Calibration Unit. During the last year, we performed the instrument AIV at the integration site in Europe. It is still ongoing. We present an overview of the flow for validation of the scientific and technical requirements, after integration of the sub-systems with some results as highlights. Further, we give an overview of the methodologies used for planning and managing the assembly of the sub-systems, their integration, and tests before the acceptance of the instrument in Europe (PAE). SOXS could be used as an example for the system engineering of an instrument of moderate complexity, with a large geographic spread of the team.

The WSS is a subsystem being designed and manufactured by the CENTRA team (Portugal) for the ESO ELT first light instrument METIS. The WSS consists of three substructures – the support system (ELP), the alignment system (CAS), and the access and maintenance system (RIG). In total, the WSS dimensions are approximately 6 × 6 × 6 meters. In order to fully assemble, integrate, and test such a large structure, an integration hall of at least 2.5 times the WSS volume would be required to accommodate the necessary lateral and vertical clearance around WSS. Such integration halls are not readily available or accessible. In order to overcome this challenge, we have devised a 3-step strategy to assemble, integrate, and test the WSS at three different locations in three different configurations.

Moving into the era of Extremely Large Telescopes (ELT), the size and complexity of the instruments increased significantly while constraints and requirements remain tight. NOVA follows a monolithic design strategy, meaning that the size of individual components scales with the size of the instrument. To enable the manufacturing and assembly of the largest components at the required precision, NOVA has invested in a new facility for ELT-era instrumentation: NOVA Manufacturing and Assembly of eXtreme instrumentation (MAX). Here we introduce the capabilities of NOVA MAX, which includes a 5-axis CNC milling machine and a Coordinate-Measuring Machine (CMM) in a temperature-stabilized environment. The CMM is located in a cleanroom with temperature variations < 0.5K/24 hours, enabling micron-level verification and fine-tuning during assembly. This unique assembly facility is crucial when producing large size one-off instruments. We report on, amongst others, the tolerances, dimensions, and loads that can be achieved with both machines and present the first components that have been manufactured for the METIS and MICADO ELT instruments.

Change is inevitable in large, big-budget operational programs. Embracing, rather than resisting, change is key to being proactive. It also keeps teams motivated as it’s another avenue for leadership to “listen” to what is going on at the team level. At Rubin Observatory, an agile approach to budgeting has been implemented, following related experience in previous High Energy Physics experiments. Annually, a ground-up review, to address changing needs, priorities and emerging issues, is carried out across all departments of the Rubin Operations organization. This “annual scrub” provides an opportunity to adapt and be nimble to changing situations that can affect resources and budgets. This paper provides details on the importance of an annual budget scrub, the processes followed, the tools used, and how the cycle continues year on year.

In the context of PLATO Camera Subsystem development, it has been decided to take advantage of MBSE methodologies using Enterprise Architect by Sparx Systems as tool. A Local SysML Camera model for PLATO mission1 has been built from different Excel spreadsheets, i.e. Verification Control Matrices, released by Subsystems. Same approach has been used for the Camera-System itself. The complete flow-down of requirements has been created in order to easily identify and monitor any impact on the design due to changes, deviations and non-compliances. The model can be updated at any time importing Excel spreadsheet while it can be used as source to export documentation needed during formal reviews, both as Word and Excel files. In addition, Model architecture and constraints have been created through Block Definition Diagram and Internal Block Diagram so that structure, interfaces as well as interaction between different items, can be easily identified and monitored at both System and Subsystem level.

Morfeo (Multi-conjugate adaptive Optics Relay For ELT Observations) is an adaptive optics module able to compensate the wavefront disturbances affective the scientific observation. It will be installed on the straight-through port of the telescope Nasmyth platform to serve the first-light instrument MICADO and with the provision for a future second instrument. The module underwent the Preliminary Design Review in 2021 and is expected to be commissioned in 2029. In this paper we present a synthesis of the System Engineering approach adopted to manage the development of the instrument assessing the criticalities of phase B (preliminary design) and preliminary phase C (final design). We will discuss the evolution of the system engineering approach, identifying within the MBSE framework the evolution of the various modelling artefacts. towards the requirements. We will detail the criticalities of the system engineering with a particular focus onto the management of the interfaces between subsystems and external systems (Telescope, other instruments…).

Recently, the Italian astronomical community has begun adopting Model Based System Engineering (MBSE) for the development of complex instruments. A significant challenge is the establishment of a robust and flexible method to manage all system aspects, among which the interfaces. This paper presents an in-progress method to trace and verify the interfaces of ANDES, the high-resolution spectrograph for the ELT telescope. The method is part of a customization of SysML language capabilities in Cameo Systems Modeler to meet the needs of the astronomical field. The method uses the nature of the interfaces to populate the interface blocks used to represent the interfaces in the system and to store the numerical and literal values that define the interfaces. The verification process checks if the client side complies with the constraints the host imposes. This whole process employs the use of computational blocks prepared in advance and reused for each interface to lighten the set-up effort and reduce human errors. The application of this methodology shall largely improve interface management leading to more efficient and safer evaluations compared to traditional methods.

The Italian astronomical community has begun adopting Model Based System Engineering (MBSE) to develop complex instruments using Cameo Systems Modeler targeting various system engineering tasks including requirements management, system structure management, activities modelling and simulation, and many more. Lately, the focus moved also to managing the system interfaces and the associated cabling and connectors. The proposed methodology uses interface blocks to represent the connectors and their location in the system. The interface blocks generate a proxy port owned by the structural element they are applied to. These ports are then connected to represent the interactions among parts, subsystems, and with external actors using SysML connectors. The connectors are then refined through association blocks also used to represent the cable with all their characteristics. The association blocks are linked to the structural blocks as their parts leading to their inclusion in the PBS of the subsystems. The main output is a table listing all the cables of the system, their connectors, the system parts they connect, and other specifics of the cable like its length, weight, and so on.

Efforts in concept study support of research projects at QUP are presented. We established the CRDF (Concurrent Research Design Facility), where multidisciplinary experts come together concurrently and can use various software tools to make the concept concrete. We also defined a CML (Concept Maturity Level) checklist specifically designed for research, based on the CML framework used in space missions. We report the achievements of the first concept study support, impressions from participants, and lessons learned to improve the next support.

The ESO/ELT ANDES (ArmazoNes high Dispersion Echelle Spectrograph) project successfully completed the system architecture review and is currently finalizing its preliminary design phase. ANDES is the high-resolution spectrograph for the ELT (ESO Extremely Large Telescope) capable of reaching a resolution of R ~ 100,000 simultaneously, in a wavelength range between 0.35 -2.4 µm (goals included), characterized by high-precision and extreme calibration accuracy suitable to address a variety of flagship scientific cases across a wide range of astronomical domains. To fulfill the required specifications the proposed design adopts a modular approach where the instrument is split in four individual spectrographs, each fiber-fed, and thermally and vacuum stabilized. A dedicated front-end which host a single conjugated adaptive optics module, collects either the light from the telescope or from a calibration unit feeding in turn the individual spectrographs. To master the described complexity the same modularity is reflected also at the project management level: each of the 9 subsystems (counting also the software as a standalone subsystem) is under direct responsibility of different teams coordinated by the ANDES project office. The high distribution and the large community involvement, consisting of 24 institutes from 13 countries, represent certainly a challenge from the project management point of view. In this paper we present the project management approach we envisaged to master successfully all the ANDES project phases from the finalization of the preliminary design up to commissioning on-sky; in particular we will describe in detail the risk management and PA/QA activities we have foreseen to assure appropriate risk mitigation and an overall high-quality standard required for the ANDES project.

There is growing interest by operational ground based observatories to follow formal project management methodologies in order to better plan and execute their projects. But the rigors of industry standards are far too excessive and costly for most of these observatories and their unique infrastructure and instrument upgrade projects. Instead, we suggest extracting the best practices through careful and intentional tailoring of conventional methodologies so as to fit the authentic needs and goals of the observatory without severe transformations of their existing staff, budget, or culture. Only then will the initiative of more formal project management be embraced and the true benefits realized.

The Atacama Large Millimeter/submillimeter Array (ALMA) Band 1 receiver covers the frequency band between 35-50 GHz. The project achieved the successful delivery of 73 Band 1 receiver units to ALMA telescope site and ready for cycle 10 observation. This paper delves into the implementation of Project management methodologies applied during the both receiver development and production phases. Furthermore, the paper presents the lessons learned and challenges faced, and offer for the future endeavors in applying the project management in the scientific research projects.

Center for the Gravitational-Wave Universe at Seoul National University has been operating its main observational facility, the 7-Dimensional Telescope (7DT) since October 2023. Located at El Sauce Observatory in Chilean Rio Hurtado Valley, 7DT consists of 20 50-cm telescopes equipped with 40 medium-band filters of 25 nm full width at half maximum along with a CMOS camera of 61 megapixels. 7DT produces about 1 TB per night of spectral mapping image data including calibration, and the byproduct of the data reduction pipeline once our planned three layered surveys (Reference Imaging Survey, Wide Field Survey, and Intensive Monitoring Survey) start in 2024. We are expecting to generate 1 PB per year by combining raw data, reduced data, and data products (e.g. calibrated stacked images, spectral cubes, and object catalogs). To incorporate this huge amount of data, we now have a data storage for 1 PB which we will increment by 1 PB per year. We also have a high-performance computation facility that is equipped with 2 NVIDIA A100 GPU cards since we plan to carry out real-time data reduction and analysis for follow-up observation data of gravitational wave events. To incorporate this, we established a high-performance network between the facilities in Korea and Chile. Taking advantage of the high-performance network, we have been carrying out fully remote operations since October 2023. In this talk, we present details of designing, planning, and executing the ground-based telescope facility project, especially within low-budget academic environments. While we cover as much ground as possible, we will emphasize human resource management, project risk management, and financial contingency management.

PLATO (Planetary Transits and Oscillation of Starts) will be used for finding the hugest amount of exoplanets ever found and to characterize them together to the associated star activity evaluation through its astroseismology. For such a purpose, 26 telescopes will be mounted on the same platform: 24 of them, called ‘normal’ and composed of four full-frame CCDs and the last 2, known as ‘fast’ composed of four frame-transfer CCDs. In both cases, CCDs will be installed on their respective focal plane assemblies (FPAs). For completing the detection chain, they are using their front end electronics (FEE), being the optics and opto-mechanics of the telescope optical unit (TOU) the last element of the PLATO CAMs. As a part of the payload development and assembly and integration and test, the PLATO CAMs are required to be calibrated and tested on simulated working conditions. INTA is one of the European institutions (together to IAS and SRON, in France and Netherlands, respectively), in which such telescopes testing and calibration is carried out. As a part of the product assurance activities, a protocol for reaching safe conditions on the telescopes during TVAC testing under any unexpected and dangerous event happed was prepared. In this paper, we are describing the need of the protocol activation for answering to one of the worst events that could be present during a TVAC testing campaign: an unexpected power outage making the vacuum pumps critically fail. The room conditions recovering in a safe way is reported on.

VSTPOL is a project to provide a new polarimetric capability to the VST. With its 2.6m primary mirror and 1 degree × 1 degree field of view, the upgrade will make the VST the first large wide field survey telescope with optical polarimetry, filling a specific niche in the astronomical instrumentation landscape. The polarimetric mode will replace the electro-mechanical system that hosts the ADC, which currently sits unused, so that the filter can be accommodated without compromising the ordinary optical configuration. The upgrade requires the design of the mechanical interface to the telescope structure and optics, and the integration of the instrument electronic and software systems. In this paper we present an overview of the approach adopted for the project management and system engineering towards the design of the polarimetric mode addition. In particular, this includes the activities related to the definition of schedule, product and work breakdown structure, deliverables, technical requirements analysis and interfaces.

Parametric cost models can be used by designers and managers to compare between major architectural cost drivers and allow high-level design trades; enable cost-benefit analysis for technology development investment; and, provide a basis for estimating total project cost between related concepts. Previously, NASA Marshall Space Flight Center developed two parametric first-article optical telescope assembly cost models – one based on aperture diameter and the other based on primary mirror segmentation – using a database with 47 total ground and space telescopes. This paper updates these models to FY23 current dollar and develops a new volume-based model. The purpose of the volume model is to investigate potential cost impact of on-axis versus off-axis telescope configurations. Finally, this paper applies these three models to each of the three the Habitable Worlds Observatory Exploratory Analytical Cases.

Parametric cost models offer a lot of utility in planning and comparing different missions and concepts. Furthermore, they have a significant advantage over other estimating methodologies as they can be quickly and easily replicated. The cost model presented in this paper focuses on estimating the most likely cost for the X-ray Mirror Assembly (XMA) of space-based X-ray telescopes with grazing incidence optics. The authors recognize the complexities of generating a single cost model that covers multiple fabrication techniques, so they have limited this preliminary study to techniques used on previous and current missions, such as direct polished glass full shell, replicated, and foil optics. Pulling from the database developed for this study, the following 2-parameter model was created: XMA$ (FY23) = $0.35M × A ^{(−𝟏.𝟎𝟓)} × P ^{𝟏.𝟎𝟕} For this model, A is the angular resolution measured in arcsec half-power diameter (HPD) and P is the projected area of the mirror module measured in cm². This model explains 98% (adjusted R squared) of the cost variation between 6 space-based X-ray telescope assemblies that used or are currently using grazing incidence optics. The parameters chosen for this model center around polishing cost, which is the largest contributor to XMA cost. More specifically, the angular resolution depends on the polishing quality, and the projected area depends on the total polished area. Future analyses will gauge the impact of incorporating similar suborbital (balloon-borne and sounding rocket) telescopes into the database in addition to telescopes utilizing other types of optics and optics fabrication techniques.

The Italian National Institute for Astrophysics (INAF) groups together 16 Observatories and Institutes. Each hosts one or more laboratories and workshops, to support technological research, operations and maintenance. This results in a vast panorama of facilities, instrumentation, equipment and skills. During a recent meeting, the INAF technological community clearly expressed the need to share information in order to more easily find tools, facilities, skills, or whatever could be of interest, to increase the working efficiency and minimize dead times and costs. We addressed this need and started developing an interactive tool called MIRTA (Interactive Map for Technological Research in INAF), aimed to effectively collect and share all this information. Its use cases can be very simple, such as, for example, solving a contingent software or technical problem or finding a specific device, or more complex, such as finding a staff member with the necessary skills to collaborate in a new or existing project.

The astronomy society is undergoing a massive series of disruptions. From the blooming field of artificial intelligence to worldwide pandemics and to capturing the first-time historic images of certain celestial phenomenon; permanent shifts are reshaping this science community. Project management (PM) is now the most important method for astronomy leaders in this society to handle these changes for a positive and desirable outcome. It is a challenge to be a project manager in the astronomy world which is driven by effort, when progress and results are what is required from a project manager to deliver a successful project. Since PM is the essential model for creating value in all private industries, now non-profit organizations are pressured to follow the same principles that composes a project, which determines whether the project's life-cycle was a success. If governments, non-profit organizations, and educational facilities focus on these principles and apply their associated functions, project success will be almost guaranteed. Throughout the astronomy society, forward-looking observatories will set themselves up for sustainable growth. This article will talk about the observations of the author on the challenges to apply PM principles in operational observatories and how to follow PM principles dutifully in future projects for long lasting observatories.

HARMONI is the first light visible and near-IR integral field spectrograph for the ELT. It covers a large spectral range from 470nm to 2450nm with resolving powers from 3300 to 18000 and spatial sampling from 60mas to 4mas. It can operate in two Adaptive Optics modes – SCAO (including a High Contrast capability) and LTAO – or with NOAO. The project is preparing for Final Design Reviews. From the perspective of data reduction, HARMONI introduces unique challenges due to its multiple adaptive optics modes, four spatial scales, eleven gratings, and two distinct NIR detector read-out modes. Capitalizing upon CRAL's experience in developing instrument simulators, this complexity prompted the development of the HARMONI Instrument Numerical Model (HINM). Built upon standard astrophysical Python frameworks, this software uses the Fourier optics concept to propagate a wavefront through the instrument, and leverages existing simulation tools for adaptive optics, sky and detector simulation. This enables the generation of synthetic detector read-outs for both calibration and science exposures. This paper highlights the crucial role played by the HINM simulator to develop the data reduction pipeline and elaborate instrument calibration procedures.

We present a comprehensive overview of the collaborative efforts between the End-to-End (E2E) Simulator and the Data Reduction Software (DRS) team, focusing on the modeling of the U-band efficient Cassegrain spectrograph CUBES (ESO-VLT). The E2E model is a Python-based numerical simulator capable of rendering synthetic raw frames with high precision for both astronomical and calibration sources, starting from their 1-d radiation spectra up to the data produced by the detectors. Data from the E2E are processed by the prototype Data Reduction Software (pDRS), a Python library which implements the critical algorithms of the DRS. The PDRS performs wavelength calibration and extracts a 1-d spectrum from one or more reduced science exposures. The 1-d spectrum produced by the extraction routine is meant to be compared directly with the input spectrum fed to the E2E, actually “closing the loop” allowing for a real end-to-end assessment of the instrument capabilities.

The computational complexity of integrated structural-thermal-optical performance models, particularly for one-of-a-kind telescope missions, often limits the maximum feasible number of analysis cycles. Applications requiring a large number of model evaluations, such as uncertainty quantification and sensitivity analysis, can become infeasible if the number of required iterations for the analysis exceeds the allocated computation time or budget. Another major obstacle to the sensitivity analysis of integrated models is the dependence between variables, as correlation between the variables changes the contribution they have on the variance in output model predictions. This paper presents an integrated modeling methodology that seeks to reduce the model’s computational cost while retaining sufficient accuracy for sensitivity analysis. Additionally, an estimation of the closed sensitivity indices is presented for the fully integrated model, taking into account the dependence between variables in structural-thermal-optical performance models.

The Mid-infrared ELT Imager and Spectrograph (METIS) is one of the first-light scientific instruments for the ELT. The common fore optics (CFO) sits at the heart of METIS, conditioning the beam and distributing the light across the wavefront sensor and science channels. To ensure it can reach its science goals, rigorous analysis of manufacturing and alignment tolerances is essential. For the CFO, an end-to-end tolerancing system was developed, integrating component level analyses, FEA results, as-built data to continuously optimize system performance during the design phase, as well as manufacturing and assembly phase.

The MeerKAT+ project will extend the current MeerKAT Radio Telescope Array at the South African Radio Astronomy Observatory (SARAO) site in the Karoo region of South Africa. In this paper we present the developed methodology, instrumentation, and the current status for verifying the pointing accuracy of a single array telescope using an optical pointing telescope and a detailed Pointing Error Budget (PEB) of the radio telescope structure. We will focus on a description of the developed instrumentation, the measurement software, the testing procedures, the measurement plan based upon them, and the applied steps for data processing and analysis. The obtained results are then correlated directly to the PEB. Furthermore, we relate the acquired results from optical pointing tests to some early radio frequency pointing tests and conclude with a discussion.

The SKA MPI Demonstrator was built at the SARAO site in the Meerkat National Park in South Africa. It provided valuable experience for the MeerKAT Extension project. The commissioning of the SKA MPI Demonstrator was accompanied by the collection of a large amount of wind data acquired from the a nearby weather station. Combined with the servo-relevant measurements such as torques, motor rates, position encoder readouts, and temperatures from different locations, it provided valuable input for characterizing the influence of wind loads on the structure. We present the results of the dynamic analysis of the data collected over several months: wind torque coefficients, as well as supporting friction curves and demonstrate how this information is used in the dynamic simulations

Wide Field Optical Spectrograph (WFOS) is the first light instrument of Thirty Meter Telescope (TMT), which will be one of the wide field spectrographs for optical spectroscopy and can probe the faintest limits. In order to reach the faintest limits provided by the aperture of TMT, WFOS is designed to have multi-object slit-based spectrograph. WFOS can observe about ~60 objects in a given exposure and cover the full wavelength range in low resolution (R~1500) observing mode. Slitless spectroscopy has been popular in space based instruments, however it is not pursued in ground based observatories due to the background contamination. Considering large plate scale of TMT and oversampling of seeing disk we will be able to extract the individual spectra from WFOS slitless observing mode. Here we present the feasibility of slitless mode of TMT-WFOS and the sensitivity limit for various field densities focusing on MilkyWay satellite galaxies. We study the background contamination due to the bright targets and the density distribution of the satellite galaxy fields.

JASMINE is a Japanese planned space mission that aims to reveal the formation history of our Galaxy and discover habitable exoEarths. For these objectives, the JASMINE satellite performs high-precision astrometric observations of the Galactic bulge and high-precision transit monitoring of M-dwarfs in the near-infrared (1.0—1.6 µm in wavelength). For feasibility studies, we develop an image simulation software named JASMINE-imagesim, which produces realistic observation images. This software takes into account various factors such as the optical point spread function (PSF), telescope jitter caused by the satellite’s attitude control error (ACE), detector flat patterns, exposure timing differences between detector pixels, and various noise factors. As an example, we report a simulation for the feasibility study of astrometric observations using JASMINE-imagesim. The simulation confirms that the required position measurement accuracy of 4 milliarcseconds for a single exposure of 12.5-mag objects is achievable if the telescope pointing jitter uniformly dilutes the PSF across all stars in the field of view. On the other hand, the simulation also demonstrates that the combination of realistic pointing jitter and exposure timing differences in the detector can significantly degrade accuracy and prevent achieving the requirement. This means that certain countermeasures against this issue must be developed. This result implies that this kind of simulation is important for mission planning and advanced developments to realize more realistic simulations help us to identify critical issues and also devise effective solutions.

The Wide Field Imager (WFI) instrument of the ESA astrophysics mission ATHENA (Advanced Telescope for High Energy Astrophysics) will target the investigation in the X-ray energy range between 0.2 keV to 15 keV. The Camera Head (CH) comprises two detectors, the Large Detector Array (LDA) and the Fast Detector (FD), with respective readout timings of 2 ms and 80 µs. The LDA consists of four Large Detectors (LDs) where each one is composed of a matrix of 512 x 512 pixels of depleted p-channel field effect transistors (DEPFETs) whereas the Fast Detector is composed of 64 x 64 pixels with a pixel size of 130 µm. At the start of the WFI signal chain is the DEPFET Sensor in the CH, with which the incident photons interact to create a signal. It is read out by the (Application-Specific Integrated Circuit (ASICs) of the Front-End-Electronics (FEE) and further processed by the Detector Electronics (DE), until at the end of the signal chain, the Ground Support Equipment (GSE) is reached. Each interaction and sub-system add a significant noise contribution, leading to an overall degradation of the measurable energy resolution. The total WFI spectral performance hence depends on the spectral performance of the CH and the noise contributions from individual components along the signal chain. We present a detailed analysis that distinguishes the different noise terms, which sum up to the total noise of the system along the complete signal chain. As the performance of the signal chain is responsible for most of the critical requirements of WFI, individual contributions are either determined by specific stand-alone measurements in the laboratory, analysis, calculations or represent estimates of individual noise contributions to the entire system, as well as heritage data from previous missions. An allocation of the performance budget for the spectral resolution of both detectors of WFI is given for system engineering.

Polarization differential imaging (PDI) is a key point-spread function subtraction technique that efficiently processes out starlight and reveals faint polarized structures, such as circumstellar disks and exoplanets. This technique operates by assuming that the signal measured from a star is unpolarized, and subtracts out of the measurement. However, in the presence of polarization aberrations the starlight will be slightly polarized by the telescope that observes it. This results in a spatially-varying polarized speckle field on the focal plane of high-contrast imaging polarimeters. Current high-contrast polarimeters are roughly an order of magnitude from achieving the photon noise limit, and polarization aberrations are a contributing factor. This effect will be stronger in the next-generation 30m Giant Segmented Mirror Telescopes (GSMTs) where polarization aberrations are stronger. In this work, we present a numerical model of a high-contrast imaging polarimeter behind an adaptive optics system subject to the polarization aberrations of an GSMT-class telescope. We use this model to understand the coupling of polarization aberrations into the adaptive optics residuals that leak through to the focal plane, and compare them to what has been observed on previous polarimetric instruments. We report on the fundamental limits imposed by polarization aberrations on PDI and discuss mitigation strategies to compensate for this effect.

As the complexity of optical instrumentation for astronomy grows, computer simulation becomes an unavoidable task of the design process. Additionally, these designs frequently involve moving parts, making both the kinematic and optical simulations tightly coupled. In some cases, the integration between both kinds of simulations is hard, and software development skills are usually also required. In order to address these difficulties we introduce RayZaler: a free-as-in-freedom opto-mechanical simulation framework. RayZaler features a ray tracer that acts upon a parametric model, stored as one or more humanreadable, plain-text model files. This allows model files to benefit from the power of version control systems like Git, while keeping their syntax accessible to users that are not familiarised with software development tools. The user defines the degrees of freedom of the model explicitly in the model files, and can use them as variables of math expressions that describe the geometry of the model. In this work, we detail its most relevant features and its application to the sensitivity analyses of HARMONI, the first-light integral field spectrograph for the ELT, and discuss several simulation products.

The Simonyi Survey Telescope (SST) at the Rubin Observatory, is nearing completion. Ensuring precise image quality is essential for fulfilling the observatory’s ambitious scientific goals. To this end, the Active Optics System (AOS) will correct various factors, including gravity-induced aberrations, temperature gradients, and hysteresis. During the commissioning phase, achieving precise alignment of the telescope is critical, particularly given the wide field of view. Small errors can lead to unacceptable off-axis aberrations, especially towards the field’s edge. This paper presents an analysis tool of the impact of these aberrations on the in focus PSF moments as detected in the science field. We introduce a simplified model of the optical system under generic misalignments, designed to quickly calculate the distribution of aberrated PSF across the field. By comparing the results obtained from this model with reference data simulated using accurate ray tracing software, we can assess its accuracy and employ it to infer the state of the optical system. This work will provide an additional aid for the Rubin team during the commissioning activities.

The Giant Magellan Telescope project has invested in creating a series of computational fluid dynamics (CFD) models to analyze how aero-thermodynamic effects impact the telescope optical performance. We use several models that feed into each other for the goal of accurately determining temperature induced collimation errors. We start with thermal network modeling, using one-dimensional approximations for a long period of time. The second is a detailed CFD model of the entire telescope. This model generates a transient, three-dimensional temperature distribution within the telescope structure over a timespan ranging from a few hours to several days in a cyclical nature. These temperature maps are fed into a structural model of the telescope, using finite element and finite volume analysis, which calculates how the structural components deform in response to the temperature spatial variability. They also provide more accurate surface temperatures for dome seeing estimates. This combined thermo-mechanical model serves to quantify the telescope optical misalignment with respect to the ambient temperature diurnal variation. These thermal deformations are then fed to the telescope optical model, which conducts the ray tracing through the optics to the telescope focal plane, ultimately yielding the associated image quality. This paper outlines the computational framework developed for these purposes and showcases some of the results obtained.

The TMT International Observatory CFD model, procedure to obtain thermal boundary conditions, input/output and statistical performance analysis tools have been updated and enhanced. Zero-wind effects, component wind jitter relative to the telescope structure and heat transfer coefficient statistics have been included. Sensitivity studies are performed, and conclusions are drawn.

An aerothermal modeling framework was developed for the entire TMT International Observatory Laser Guide Star Facility, consisting of several standalone conjugate heat transfer models: laser head, laser bench array, optical path pointing arrays, beam transfer duct, top end including the laser telescope assembly, and several electronics cabinets, resolving all interior components. The primary goals were to evaluate the focus error from the thermal lens deformation, to evaluate beam jitter from the optical path difference maps along the beam path, and to obtain the temperature of all exterior surfaces. The framework provided performance sensitivity to specific inputs/assumptions and lead to improved design that meets performance requirements.

Conjugate heat transfer modeling is used to estimate the front temperature distribution, thermal deformation, and differential pressure distribution of the GMT primary mirror (M1) segments. The modeling framework validates segment temperature and thermal deformation requirements and supports the M1 optical testing underway. This paper presents the various framework models, the predicted baseline performance, and a sensitivity analysis of the impact of several heat sources on the expected thermal deformation, including simulations specific to optical testing.

The Cosmic Microwave Background Stage Four Experiment (CMB-S4) is a planned DOE/NSF ground-based experiment that will probe the entire history of the cosmos by performing millimeter-wave sky surveys to produce multi-wavelength sky maps in both intensity and polarization of unprecedented quality. To meet its ambitious and transformative science goals within a reasonable survey duration, CMB-S4 employs a rigorous Systems Engineering approach to ensure tight control of instrumental sensitivity, systematic error, and instrument down-time. This disciplined Systems Engineering framework is essential for managing the instrumental configuration within the multi-institutional structure of the project. We present an overview of the project’s Systems Engineering approach, processes, tools, and status.

As part of the strengthening of the Italian research infrastructure included in the National Resistance and Resilience Plan, a financing proposal was presented for the recovery of an ancient 19th century building located in the park of the Astronomical Observatory of Capodimonte INAF, allocating it to host INAF's first Concurrent Design Facility and the first in southern Italy. A Concurrent Design Facility (CDF) is the set of infrastructures, devices and processes that allows engineering teams with people from different backgrounds to work together, at the same time, on all the aspects of the design. This coordinated effort helps to achieve complex design definition more easily and quickly, through an engineering management protocol, compared to a “step-by-step” approach, which is the traditional method where each team works individually with only little direct interaction with each other. Concurrent engineering is extremely efficient in terms of time and effort, especially for feasibility studies and preliminary design. This article describes the project presented and the expected functionality of the new CDF, both from a technological and architectural recovery point of view.

We present the results of the Pre-Phase A study of a subsystem and components onboard the LiteBIRD mission, whose scientific objective is to study the cosmic microwave background to search for the evidence of cosmic inflation in the very early universe. The study was conducted according to systems-engineering processes. We have a draft interface requirement document (IRD) for the subsystem from the system that is one layer higher in the LiteBIRD product tree. Taking it as the “stakeholder’s expectation,” we conducted the three process groups: the system-design, the product-realization, and the technical-management processes. In the processes, we found several issues in the IRD, and started discussing to mitigate them. The results were summarized in draft baseline documents which formed a part of the input package for the mission definition review held at JAXA in 2023-24.

The benefits of systems engineering are clearly visible in space projects, which are usually distributed over several contributing institutions. For the similarly complex ground-based astronomy project GIRMOS the systems engineering work of the preliminary and critical design phases is presented, including the applied tailoring of typical methods. The resulting requirements flow-down, interface definitions and focus on essential methods could serve as a guideline for resource-limited yet complex projects.

A concurrent engineering approach to the design of astronomical instrumentation is based on experts of different backgrounds collaborating in the same environment on every aspect of the design, during one or multiple dedicated sessions, depending on the complexity of the project. This strategy is very cost effective, and, if managed properly, can optimize the way different teams interact with each other, compared to the traditional “step-by-step” approach, with each team working separately and thus generating a cascade dependency of all subsystems. As the complexity of a project increases, so does the number of teams who work together, and a progressively larger number of interactions is required to allow all the actors to talk to each other. For projects of the complexity that is often dealt with in space or ground-based astronomy, concurrent engineering has been proven to be extremely efficient in terms of time and effort, especially for feasibility studies and preliminary design, but also during the following phases. In this work, an analysis of the methodologies that are typical of a concurrent design approach is made, with a focus on the tools that can be adopted for an efficient coordination of all the people involved. These tools and methodologies will be applied to the Concurrent Design Facility in construction at the Capodimonte Astronomical Observatory in Naples, in the scope of the National Recovery and Resilience Plan project "STILES - Strengthening the Italian leadership in ELT and SKA", with the aim of significantly improving the design process of the present and future classes of astronomical instrumentation.

We present details of the recent trade study on design changes to the Wide Field Optical Spectrometer (WFOS) for the Thirty Meter Telescope (TMT)[1]. WFOS is planned as a first light instrument and will provide highly efficient imaging and multi-slit spectroscopy over the wavelength range 0.31 to 1µm across a field of view of 8.3 by 3 arcminutes. The existing baseline prior to the trade study used a laser cut metal slit mask at the focal plane to enable observation of ~50 to 80 objects simultaneously. The masks would be cut in advance of observing and installed in a cassette, allowing a mechanism to select the mask and move it into place at the focal plane. Each multi-object observation requires a dedicated mask, with a more general single long slit mask remaining in the cassette permanently. The configurable slit unit (CSU) is an alternative approach, and a design that has previously been used in MOSFIRE and FORS. A CSU uses multiple knife edges mounted on computer-controlled bars to create and position slits at the focal plane. In the case of WFOS the CSU will be capable of creating 96 separate slits with the ability to reconfigure them on the fly to adapt to seeing conditions or to respond to targets of opportunity. We detail here the decision criteria, design, and science case analysis used by the WFOS team to decide to change the baseline design of WFOS to incorporate a CSU.

A major issue for project management, besides handling schedules and deadlines, is the process of finding and extracting the most relevant information from a variety of different software solutions used by the different stakeholders. This often leads to enormously large Excel sheets that try to identify the most up-to-date versions of the documents needed, which are extremely time-consuming to maintain, inefficient for finding information, and prone to errors. The contemporary methodology we introduce represents a paradigm shift in project management, eschewing the traditional model of isolated databases for documents, such as requirements, CAD data, and Gantt chart schedules. Instead, we propose an integrated database architecture that consolidates all project management needs into a single, user-friendly repository. This, coupled with a web-based interface, facilitates the retrieval of relevant information in a straightforward and dependable manner. Illustrated through the case study of ELT-MICADO, we present the implementation of this strategy using Siemens Teamcenter, an industry standard software solution that is adapted to our specific needs. This exposition is not intended as an endorsement of the product but rather as an exemplification of one potential solution. It is acknowledged that alternative software solutions may offer comparable functionality and performance.

This paper presents the Thirty Meter Telescope (TMT) International Observatory (TIO) systematic approach to safety system design, utilizing the Laser Guide Star Facility (LGSF) as a case study. The proposed framework commences with a detailed Hazard Analysis and concludes with the definition of Safety Related Control Functions (SRCFs). The presented framework not only offers valuable insights into the safety design process but also serves as a practical guide for engineering teams involved in the development of safety-critical systems. The case study from TMT LGSF illustrates the applicability and effectiveness of this approach in real-world scenarios.

Hazard and Risk Assessment (HARA) is a critical Systems Engineering and safety activity used to ensure a safe environment for personnel and hardware. This paper discusses how TMT has tailored the Atlassian Jira tool and third-party embedded app, SoftComply Risk Manager, to provide a collaborative environment with subsystem teams in order to a develop a comprehensive HARA, starting with hazard identification and assessment and continuing through reassessment after mitigation. The paper shows how the tool was initially created for the Telescope Structure (STR) to facilitate collaboration with the National Astronomical Observatory of Japan (NAOJ) and Mitsubishi Electric Corporation (MELCO), and has since expanded to other subsystems as well as to the system-level, capturing intersystem hazards. From the system and subsystem HARAs, risk reduction actions are identified and if safety functions are used as a mitigation, they are described in terms of functional safety actions and associated SIL ratings. These safety functions are then traced to safety requirements imposed on the Observatory Safety System or on subsystems. This overall HARA process provides TMT with a comprehensive overview of all Observatory hazards and the status of the development and implementation of their mitigations thanks to the Jira and Risk Manager dashboards, risk matrix, and risk table views.

Reliability prediction in the realm of ground-based astronomy is a relatively new but highly beneficial application of reliability estimation techniques. As observatories grow in scale and complexity, reliability becomes an increasingly important feature, and a metric of system performance. At the Thirty Meter Telescope International Observatory, observing time is key to leveraging the science capabilities of the telescopes and instruments, hence maximizing the availability of all subsystems via measurable reliability information is extremely valuable. We present an analysis method that removes the barriers to completing a bottoms up reliability estimate for any opto-mechanical or electrical subsystem, and connection of the reliability estimates to FMEA and critical spares analysis.

The imminent construction of a ten-meter-class ground-based astronomical telescope in China signifies the nation’s remarkable progress in optical instrumentation. Currently, the integration of large telescopes with singlemode fibers, facilitating light delivery to compact photonic spectrometers, or enhancing the performance of radial velocity measurements through high-resolution spectrographs, presents an active and challenging frontier in the near future. Furthermore, this endeavor aims to elevate the accuracy and resolution of long-baseline optical interferometry, marking a crucial stride in advancing observational capabilities. Comprehensive end-to-end simulation platform are employed for on-sky coupling to single-mode fibers(SMF). Utilizing open-source atmospheric models and adaptive optics software as baseline and core simulators enhances the evaluation process. Subsequently the phase functions being corrected by adaptive optics are extracted for further evaluation. Several previously overlooked factors are identified and addressed. The simulations are integrated into optical software, enabling the execution of physical optics propagation and a comprehensive, dynamic evaluation of fiber coupling performance. The impact of each component of the system has been analyzed, and statistical results could be obtained to identify the optimal component parameters. The error budget determination procedure is outlined as well, ensuring a relative completeness in assessing potential uncertainties. This research integrates end-to-end optical platform, where preliminary results have been obtained.