The Iodine Satellite (iSat) Project Development through Critical Design Review (CDR)

The stability and control characteristics using a wind tunnel test data process are proposed and developed to investigate the stability and control characteristics of a CS-VLA certified aircraft and to comply with the CS-VLA subpart B at the preliminary design review (PDR) and critical design review (CDR) stage. The aerodynamic characteristics of a 20% scale model are provided and investigated with clean, rudder, aileron, elevator, and winglet effects. The Mach and Reynolds correction methods are proposed to correct the aerodynamics of the scale model for stability and control analysis to obtain more reliable and accurate results of the full-scale model. The aerodynamic inputs and moment of inertia (MOI) comparison between the PDR and CDR stage show good agreement in the trends of stability and control derivatives. The CDR analysis results with the corrected wind tunnel test data and accurate MOI are investigated with respect to the longitudinal and lateral stability, control, and handling qualities to comply with the CS-VLA 173, CS-VLA 177, and CS-VLA 181 for finalizing the configuration in the CDR stage.

The CHIME (Copernicus Hyperspectral Imaging Mission for the Environment) mission is a key component of the European Union’s Earth Observation programme, Copernicus. The CHIME satellite will carry a unique payload designed to provide routine hyperspectral observations. Its HyperSpectral Instrument (HSI) will acquire a continuous spectral signature ranging from 400 to 2500 nm at a spatial resolution of 30 meters. In 2024, the Structural and Thermal Model (STM) of the HSI underwent thermal vacuum testing, a crucial step towards the Critical Design Review (CDR) scheduled for early 2025. This paper presents the results of the STM thermal balance test for the HSI, including thermal model correlation, and the status of the thermal control design at CDR. The focus is on key elements of the thermal control system, such as the baffled passive cryogenic radiator, which cools three separate focal planes to 170 K. The radiator is connected to the focal planes via a cryogenic chain that utilizes graphite thermal straps and ethane heat pipes. During the STM thermal balance test, the cryogenic chain exhibited higher-than-expected temperatures, prompting an investigation into potential additional heat leak sources within the instrument design and test equipment. This paper will detail the findings of this investigation, the performance of the ethane heat pipes under gravity conditions, and the overall results of the thermal balance.

Micro, Small, and Medium Enterprises (MSMEs) encourage the country’s economy to develop rapidly. Pempek Kabeja MSMEs is one of the Frozen food businesses located in Cirebon, which is growing and has many enthusiasts because of its instant, easy, and practical nature. However, some problems exist in Kabeja MSMEs, namely the process of recording and bookkeeping in the sales and production process, which is still manual, where the recording still uses paper. This research requires business owners to improve services for the convenience of consumers and to increase competitiveness between competitors. Improvements include implementing an information system for Pempek Kabeja MSMEs, which can simplify the process of recording and accounting for production and sales because, with an information system, the process will be better. The development of this MSME information system uses the System Development Life Cycle method. SDLC has a framework, one of which is Use Case Driven Object Modelling with UML, commonly called the ICONIX process. The ICONIX Process is a lean, efficient method for using case-driven UML modeling that fully covers object-oriented analysis and design using a core set of UML diagrams and methodologies. Robustness analysis, a technique for bridging the gap between analysis and design, is its major activity. The ICONIX process has six stages: requirements, analysis / preliminary design, preliminary design review, detail design, critical design review, and implementation. However, this study did not conduct the critical design review stage. The result of this research has integrated information systems so that it can help the production and sales process of Pempek Kabeja MSMEs more effectively and efficiently.

The intent of this publication is to provide an overview of the development of the VINCI® engine over the period 2014–2015. The VINCI® engine is an upper stage, cryogenic expander cycle engine. It combines the required features of this cycle, i. e., high performance chamber cooling and high performance hydrogen turbopump, with proven design concepts based on the accumulated experience from previous European cryogenic engines such as the HM7 and the VULCAIN®. In addition, its high performance and reliability, its restart and throttle capability offer potential applications on various future launcher upper stages as well as orbital spacecraft. At the end of 2014, the VINCI® successfully passed the Critical Design Review that was held after the major subsystem (combustion chamber, fuel and oxygen turbopump) had passed their own Critical Design Review all along the second half of 2014. In December, a Ministerial Conference at government level gave priority to the Ariane 6 program as Europe future launcher. In the framework of this decision, VINCI® was confirmed as the engine to equip Ariane 6 cryogenic upper stage engine. This publication shows how the VINCI development is progressing toward qualification, and also how the requirements of the new Ariane 6 configuration taken into account, i. e., offering new opportunities to the launch system and managing the new constraints. Moreover, the authors capitalize on the development already achieved for the evolution of Ariane 5. In parallel to completing the engine development and qualification, the configuration and the equipment of the propulsive system for Ariane 6 such as the components of the pressurization and helium command systems, board to ground coupling equipment, are being defined.

We present a case study showing a human-competitive design of an evolved antenna that was deployed on a NASA spacecraft in 2006. We were fortunate to develop our antennas in parallel with another group using traditional design methodologies. This allowed us to demonstrate that our techniques were human-competitive because our automatically designed antenna could be directly compared to a human-designed antenna. The antennas described below were evolved to meet a challenging set of mission requirements, most notably the combination of wide beamwidth for a circularly polarized wave and wide bandwidth. Two evolutionary algorithms were used in the development process: one used a genetic algorithm style representation that did not allow branching in the antenna arms; the second used a genetic programming style tree-structured representation that allowed branching in the antenna arms. The highest performance antennas from both algorithms were fabricated and tested, and both yielded very similar performance. Both antennas were comparable in performance to a hand-designed antenna produced by the antenna contractor for the mission, and so we consider them examples of human-competitive performance by evolutionary algorithms. Our design was approved for flight, and three copies of it were successfully flown on NASA's Space Technology 5 mission between March 22 and June 30, 2006. These evolved antennas represent the first evolved hardware in space and the first evolved antennas to be deployed.

In efforts to support the Artemis mission which seeks to return to the lunar surface, this research seeks to tackle one of the biggest issues faced on the lunar surface. Lunar soil is a hazardous threat to both spacesuit functionality and astronaut health. Due to characteristics such as being electrostatically charged, jagged edged and extremely fine in composition (> 10 microns). For the past three years the research focus has been experimenting with previously established electrostatic cleaning systems that were not able to achieve 100% cleaning efficiency. Removing soil particles smaller than 10 microns became a main concern as they were the most difficult to remove. Previous iterations were able to achieve up to 98% cleaning efficiency and building upon this success the research developed new methods of transmitting an electrostatic field by using thin films which are more beneficial to spacesuit fabric. The system during certain test pushed the limits by achieving a cleaning efficiency of 99.5%. This study discusses the process of using systems engineering to successfully take the system from inception to completion. This process illustrates the project progress during major reviews such as System requirements review, preliminary design review and critical design review. Also, the schedule and budget concept of operations and system hierarchy is discussed as it progressed throughout the project. Various trade studies, reliability and safety of the project is also examined in this study. The system is finally built and tested to display its feasibility and efficiency to match that which was envisioned during the inception of the project.

One of the few things certain about development of complex systems is the requirements for the system will remain uncertain late into the development program. Even though we recognize this, why do many programs assume that requirements will not change (gambling) or treat requirement change as a risk rather than a certainty? An analysis of gas turbine engine control systems requirements shows that typically 50% will change between Critical Design Review and Entry into Service. This requirements uncertainty manifests as technical risk to the programme. This paper evaluates the impact of not managing these uncertainties and describes how applying Systems Engineering principles can reduce this effect.Design iterations produce rework, and without technical risk management, ~50% of the effort will be wasted in producing unacceptable designs. In turn, correction of these errors will create more rework. This results in much iteration and cumulatively twice as much work is required to produce a mature design. With technical risk management, less than 10% of the design effort will result in rework, giving a mature product with far less iteration.Investigation into the source of the product development lifecycle problems indicates many escapes occur during requirements definition and review. Around twice as many changes are driven by errors in requirement definition by the developer, compared to customer‐driven requirements changes. In addition, many of these escapes are detected later in the product development lifecycle than they could have been found, resulting in further escalation of the cost of product development. This paper compares and contrasts the root causes for these escapes during system, software and hardware development and looks at the differences in consequences.The role of the Systems Engineer is critical in addressing these problems. In addition to effective elicitation of requirements from stakeholders, the Systems Engineer must manage volatility and apply robust design principles to protect against the impact of requirements changes. The Systems Engineer must flow requirements effectively from system to sub‐system, from sub‐systems to components and provide the “glue” that results in the integrated system being more than the sum of its parts.Some tools and techniques are presented to help Systems Engineers identify probable sources of uncertainty and provide effective mitigations. An approach is also presented for assessing the technical risk management “maturity” of a project, based upon ‘best practice’ approaches taken from those projects achieving low levels of engineering scrap and rework during their development phase.

Flight and ground system operability has been a focus area on the Europa Clipper Project since early in its formulation phase. This has given the operations team the opportunity to influence the design, with a goal of increasing overall system operability. This paper presents example operability challenges, opportunities, and solutions arising from the Critical Design Review (CDR) system design. The integrated wing assembly design directly couples a scientific instrument (the REASON sounding radar) to the spacecraft’s power source (solar array wing panels). Impacts to mission operations of this design include: increased slew durations; solar array pointing constraints during inner cruise, Europa flybys, and orbit trim maneuvers; and stray light intrusions into the stellar reference units’ keep out zones. The use of CCSDS File Delivery Protocol (CFDP) Class-2 for reliable downlink of the large volume of Europa Clipper science data is described, along with nominal and off-nominal use cases. The effort to improve post-launch spacecraft visibility by adding a third low-gain antenna to the spacecraft is detailed. The design of the bulk data store has necessitated the implementation of accountable data products (ADPs), accountability identifiers (AIDs), and metadata packets to provide end-to-end science data accountability. To streamline and automate the flight rules generation and checking process, a first order and temporal logic-based solution of expressing flight rules without ambiguity, and whose programmatic implementation can be automated, is proposed. The focus on operability has had a positive influence on Europa Clipper design decisions, although cost, schedule, budget, heritage, and other technical concerns have many times outweighed operability concerns. However, experience to date demonstrates that this approach to operability results in more thorough, balanced consideration of the effect of early design trades and decisions on the operations phase of a mission than seen in many previous missions, and provides operations development insight into prioritizing work to go.KeywordsOperabilityCFDPFlight rulesSolar array

The Square Kilometre Array Observatory (SKAO) will construct two radio telescopes: SKA-Low in Australia and SKA-Mid in South Africa. When completed, the Square Kilometer Array (SKA) will be the largest radio telescope on Earth, with unprecedented sensitivity and scientific capability. The first phase of SKA-Mid (called SKA1-Mid) includes an array of 197 dish antennas incorporating the recently completed MeerKAT dishes to cover the frequency range of 350 MHz to 15.4 GHz. The 19 Tb / s digitized data stream is transported from the dishes in the remote Karoo to Cape Town where data are correlated and processed through high-performance computing systems. The demanding scientific performance requires extremely accurate timing and synchronization of the data measured by the distributed dishes. The combination of large-scale deployment, significant real-time processing, geographic distribution, and limited budget poses significant challenges for the physical, control, and processing architectures. We present the architectural highlights of the SKA1-Mid Telescope baseline design, for which its Critical Design Review was completed in 2019 and construction was started in July 2021.

Hyperspectral Imager Suite (HISUI) is a Japanese hyperspectral mission to obtain optical images ranging from visible to shortwave infrared region. The mission instrument will be on-board the Japanese Experiment Module (JEM) of the International Space Station (ISS) in early 2020. The sensor obtains spectral images of 185 bands with the ground sampling distance of 20x31 meter, which succeeds the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) in the visible and shortwave infrared region. After the critical design review in 2014, integration of the Flight Model (FM) of HISUI sensor was completed in the beginning of 2017. In parallel, the bus system connecting HISUI sensor and the JEM External Facility (EF) is developed, which has the function of a data recorder, electric control, navigation, thermal control and mechanical structure is under development. Since hyperspectral data needs an accurate calibration, the ground-based test is under way. In this work, the present status of HISUI sensor is presented. Sensor performances in terms of optical distortion and radiometric performances are described based on the FM tests.

Dawn Discovery mission to Vesta and Ceres: Present status

A current problem that severely affects the performance of spacecraft is related to slosh dynamics in liquid propellant tanks under microgravity conditions. The confidence in computational fluid dynamics (CFD) predictions are low because of the lack of benchmark against experimental data. The goal of the SPHERES Slosh Experiment (SSE) is to acquire long-duration, low-gravity liquid slosh data aboard the International Space Station. The proposed experimental platform consists of a tank, partially filled with fluid, cameras, and inertial sensors to monitor the fluid distribution in the tank. Currently the SSE has passed NASA’s Critical Design Review (CDR) and Phase 0/I-II Flight Safety Review (FSR). The manufacture and qualification testing of the flight article has been completed. The Slosh payload is scheduled to be launched in December 2013 with on-orbit experiments to begin shortly thereafter.

The Extreme Ultraviolet Imager (EUI) on-board the Solar Orbiter mission will provide full-sun and high-resolution image sequences of the solar atmosphere at selected spectral emission lines in the extreme and vacuum ultraviolet. After the breadboarding and prototyping activities that focused on key technologies, the EUI project has completed the design phase and has started the final manufacturing of the instrument and its validation. The EUI instrument has successfully passed its Critical Design Review (CDR). The process validated the detailed design of the Optical Bench unit and of its sub-units (entrance baffles, doors, mirrors, camera, and filter wheel mechanisms), and of the Electronic Box unit. In the same timeframe, the Structural and Thermal Model (STM) test campaign of the two units have been achieved, and allowed to correlate the associated mathematical models. The lessons learned from STM and the detailed design served as input to release the manufacturing of the Qualification Model (QM) and of the Flight Model (FM). The QM will serve to qualify the instrument units and sub-units, in advance of the FM acceptance tests and final on-ground calibration.

I. INTRODUCTION The Broadband Radiometer (BBR) is an instrument being developed for the ESA EarthCARE satellite. The BBR instrument objective is to provide measurements of the reflected short-wave (0.25-4.0 µm) and emitted long-wave (4.0-50 µm) top of the atmosphere (TOA) radiance over three along-track views (forward, nadir and backward). The instrument has three fixed telescopes, one for each view, each containing a broadband detector. The BBR instrument is led by SEA in the UK with RAL responsible for the BBR optics unit (OU) while EADS Astrium is the EarthCARE prime contractor. A detailed description of the instrument is provided in [1]. The BBR detectors consist in three dedicated assemblies under the responsibility of INO. The detectors development started in 2008 and led to the design and implementation of a new gold black deposition facility at INO [2], in parallel with the preliminary and detailed design phases of the detector assemblies. As of today, two breadboard models and one engineering model have been delivered to RAL. In the BBR OU each detector mechanically interfaces with the teles cope and electrically with the front-end electronics (FEE). The detectors’ development is now at the Critical Design Review (CDR) level. This paper first provides a description of the detector design along with its principles of operation. It further presents and discusses measurement and analysis results for the performance characterization of the engineering model in the context of the applicable requirements. Detector-level qualification planning is finally discussed. II. DETECTOR DESCRIPTION The detectors are required to provide fast pixel response time (< 6 ms), uniform spectral response over the entire spectral range (0.25-50 µm), and an NEP lower than 3.7 nW at 17 Hz (after time averaging over a period of 20 ms). The engineering model detector is shown in Fig. 1, with (right) and without (left) its cover. Each detector consists of an uncooled focal plane array (FPA) hybridized with a readout integrated circuit (ROIC). The FPA is based on INO’s VO

NASA’s fourth New Frontiers mission, Dragonfly (Turtle &amp; Lorenz 2024), will land a robotic octocopter on Saturn’s moon Titan in 2034 to study its prebiotic chemistry, constrain its habitability, and search for potential chemical biosignatures. The target landing site will be a portion of the Shangri-La sand sea just south of Selk Crater, an 80-km impact structure (Lorenz et al. 2021). Taking advantage of Titan’s low gravity and thick air, Dragonfly will aerially traverse to over twenty distinct landing sites on dune, interdune, and icy crater terrains (Lorenz et al. 2018).Figure 1. Dragonfly is a large 4.5-meter long, almost 1000 kg aerial rover with a sophisticated and high-mass scientific payload. It will spend its 3.3-year nominal surface mission exploring and sampling Titan’s sand dunes, interdunes, and the icy 80-km Selk Crater impact structure.On the ground at those sites we will employ our four scientific instruments: a mass spectrometer (DraMS Trainer et al. 2022), a gamma-ray/neutron spectrometer (DraGNS), seven cameras (DragonCam), and a geophysical and meteorological suite (DraGMet). The DrACO sampling system will drill into the surface and ingest surface samples by means of a hydraulic vacuum cleaner. The vehicle spends over 99% of its time on the ground, and therefore while it can and will fly, the term “relocatable lander” brings to mind a better sense for the operations that we expect to execute on Titan.We seek to determine how far organic chemistry has progressed, to ground-truth the global methane meteorological cycle, to measure the modes and rates of surface geologic processes, to constrain when and where water and organics might have mixed, and to look for evidence that either water- or hydrocarbon-based life may have existed on Titan (Barnes et al. 2021). Our science objectives with respect to organic chemistry are to measure compositions of materials in different geologic settings and to determine presence and abundance of key molecules for Earth-like life. We have goals to characterize Titan’s methane cycle by constraining the atmospheric methane moisture budget at our tropical landing site and assaying the abundance of stored liquid methane in the near-subsurface.To place our samples into context, we will need to assess their provenance which we will do by determining the conditions for aeolian transport, by determining the transport mode and history of clastic saterials, and by establishing the geologic context of sampled materials. Our fourth goal is to determine where and how liquid water may have mixed with organic material, which we will do with a seismometer to measure current lithospheric activity and, if Titan is sufficiently active seismically, to constrain the depth to Titan’s liquid-water ocean. Other instrumentation will determine the availability of near-surface water ice and constrain past geologic processes.Dragonfly finally has a goal to search for any potential chemical biosignatures on Titan as may have been produced by either extinct or extant life. Our objectives on this front are to determine enantiomeric abundance of chiral molecules, to determine if patterns exist in molecular masses and distribution, and to follow up on Huygens hydrogen indications with more and more accurate hydrogen profiles of the lower atmosphere.Dragonfly recently passed its Critical Design Review and we are fabricating hardware ahead of the launch period that opens on 2028 July 5.Figure 2. Dragonfly is a single-element mission, and will communicate to Earth directly by means of an 85-cm radial line slot array high-gain antenna, as can be seen here deployed on the ventral (top) side of the vehicle. REFERENCESBarnes, J. W., Turtle, E. P., Trainer, M. G., et al. 2021,Science Goals and Objectives for the Dragonfly TitanRotorcraft Relocatable Lander, The Planetary ScienceJournal, 2, 130, doi: 10.3847/PSJ/abfdcfLorenz, R. D., Turtle, E. P., Barnes, J. W., et al. 2018,Dragonfly: a Rotorcraft Lander Concept for scientificexploration at Titan, Johns Hopkins APL TechnicalDigest, 374Lorenz, R. D., MacKenzie, S. M., Neish, C. D., et al. 2021,Selection and Characteristics of the Dragonfly LandingSite near Selk Crater, Titan, The Planetary ScienceJournal, 2, 24, doi: 10.3847/PSJ/abd08fTrainer, M. G., Brinckerhoff, W. B., Grubisic, A., et al.2022, Dragonfly Mass Spectrometer Investigation atTitan, in The Astrobiology Science Conference(AbSciCon) 2022, 239–03Turtle, E. P., &amp; Lorenz, R. D. 2024, Dragonfly: In SituAerial Exploration to Understand Titan’s PrebioticChemistry and Habitability, in 2024 IEEE AerospaceConference, IEEE, 1–5