Journal of Space Safety Engineering最新文献

With the success of the Indian Space Research Organization (ISRO) rocket launch on March 26, 2023, Oneweb has made significant progress toward completing its low-Earth orbit (LEO) constellation. Since October 2022, an additional 156 satellites have been added to its constellation, bringing the total number of space assets to 620. This achievement signifies a 98 % completion of the planned OneWeb Gen-1 constellation, that enables high speed and low latency connectivity to high latitude regions worldwide. The full deployment of the constellation is expected to be finalized by mid 2023. As the second world's largest satellite fleet owner and operator, OneWeb prioritizes space safety and sustainability best practices to ensure harmonious co-existence with other space operators within the ever-evolving space environment. Given the substantial increase in the number of space objects over the past two years and the occurrence of fragmentation events, OneWeb aims to share its operational experience and safe navigation methodology of a large satellite fleet from orbit injection to service orbit altitude amid challenges posed by changes in the space environment. The discussion in this paper encompasses various aspects of satellite fleet operations, such as conjunction data management, implementation of space sustainability best practices, and the feasibility and versatility of low thrust electric propulsion systems in satellite maneuverability, environmental pollution reduction and effective collision avoidance efforts.

Over the past few years, numerous accidents have occurred during dangerous chemical experiments. Although there is a considerable amount of literature on laboratory safety, there is still a lack of systematic research that examines how the various laboratory systems interact and potentially contribute to accidents. The objective of this work is to lessen accidents and incidents related to Handling Energetic Materials in Research Laboratories by utilizing STPA (System-Theoretic Process Analysis). This involves examining unsafe interactions between system components, detecting potential undesired events, and implementing measures to prevent or reduce their impact. Recent literature on laboratory safety, quality standards, and interviews with lab workers were used as data sources for the STPA elaboration. As a result, it was possible to identify Unsafe Control Actions, Loss Scenarios, Causal Factors, and Safety Constraints to be considered to avoid undesired events or to mitigate their consequences during the Energetic Material Handling in research centers. It was also possible to point out key measures that can reduce waste, enhance productivity, allocate resources more effectively, decrease accidents, and, most importantly, mitigate potential hazards in laboratory work. The SPTA analysis presented a way to improve laboratory safety management and ensure a safer and more productive research environment.

Hyperloop transportation systems represent an emerging technological frontier with the potential to revolutionize both passenger and freight transportation through high-speed rail transit. However, as is common with nascent technologies, there is no consensus on the best approach to design and operate these systems safely or on the appropriate level of safety integration. Consequently, industry stakeholders find themselves lacking clear regulatory guidance for this rapidly advancing field. Drawing from the wealth of safety expertise developed by NASA over the past several decades in the realm of space exploration, it becomes evident that this robust safety methodology can effectively address safety concerns within the Hyperloop concept. Moreover, it can lay the foundation for a potential certification process that regulatory agencies can adopt. Within this investigation, the safety case approach is applied to scrutinize the Hyperloop system, comparing it to the first published industry standard for Hyperloop systems. By employing this approach, space exploration experience from program development and successful operation as well as from lessons learned from anomaly investigations is leveraged to identify numerous hazards that are not properly addressed from the published standard. This underscores the need for a more comprehensive safety framework to ensure the secure development and operation of Hyperloop transportation systems.

Real-time communications with ground support are fundamental to ensuring crew safety in space. However, there will be long delays in communication as space missions travel further away from Earth. During a time- and life-critical situation, the crew will need on-board Artificial Intelligence (AI) driven technology to support anomaly mitigation decision-making and response. This paper discusses human factors considerations to help crew problem-solving, reduce errors, and enhance safety on exploration class missions.

This paper discusses High Level Architecture (HLA) based simulation in the context of designing safety into space vehicles. Distributed simulation plays an important role to fuse the two worlds of safety on the one hand and cost effectiveness on the other hand. HLA represents a simulation system architecture framework standard and focuses on interoperability and reusability of simulation components. The article analyzes the impact of the usage of the future HLA version called HLA 4 on space vehicle design. New possibilities with an increased level of loose component coupling in combination with the establishment of a-priori interoperability by using the Space Reference Federation Object Model (SpaceFOM) standard are presented.

During orbital rendezvous, the spacecraft typically approach in the same orbital plane, and the phase of the orbit eventually aligns. Potential rendezvous and docking missions need to be emulated and tested in an on-ground facility for micro-gravity research prior to meeting the harsh conditions of space environment. For orbital docking, the velocity profile of the two spacecraft must be matched. The chaser is placed in a slightly lower orbit than the target. Since all these tasks are quite complex and the realization of space missions are very expensive, any space-related hardware or software’s performance must be tested in an on-ground facility providing zero gravity emulation before initiating its operation in space. This facility shall enable emulation conditions to mimic pseudo zero gravity. It is of critical importance to be equipped with all the necessary ”instruments and infrastructure” to test contact dynamics, guidance, navigation and control using robotic manipulators and/or floating platforms. The Zero-G Laboratory at the University of Luxembourg has been designed and built to emulate scenarios such as rendezvous, docking, capture and other interaction scenarios between separate spacecraft. It is equipped with relevant infrastructure including nearly space-representative lightning conditions, motion capture system, epoxy floor, mounted rails with robots, capability to integrate on-board computers and mount large mock-ups. These capabilities allow researchers to perform a wide variety of experiments for unique orbital scenarios. It gives a possibility to perform hybrid emulations with robots with integrated hardware adding pre-modeled software components. The entire facility can be commanded and operated in real-time and ensures the true nature of contact dynamics in space. The Zero-G Lab also brings great opportunities for companies/startups in the space industry to test their products before launching the space missions. The article provides a compilation of best practices, know-how and recommendations learned while constructing the facility. It is addressed to the research community to act as a guideline to construct a similar facility.

To reduce the risk of explosion of propellant tanks of expended spacecraft and launch vehicles with liquid rocket engines in orbit, as well as in case of emergency situation, for example, loss of orientation, the Inter-Agency Space Debris Coordination Committee recommends passivation measures, including the discharge of residual liquid propellant and pressurant gas. In ANSYS-Fluent program complex possible initial positions of liquid propellant residues in a spherical tank at its rotation under conditions of low gravitational fields are determined. The values of liquid propellant residues depending on their initial position in the spherical tank at opening of the drain line for discharge of gas–liquid mixture into the ambient space are determined. The concept of formation of two-phase flows of liquid propellant on the example of the spherical tank at tangential entry of compressed gas is offered. The relationship between the number of gas inlet points and the effectiveness of the developed method (expressed as the ratio of the mass of expelled liquid propellant to the mass of gas expended) is demonstrated. For instance, the use of 2 gas inlet points achieves an efficiency of up to 30 %, while employing 3 gas inlet points increases it to 89 %.

The development of novel space nuclear systems by governments and companies can greatly enhance space exploration, commerce, and defense capabilities. However, the predominant safety framework for space nuclear in soft law and in practice focuses narrowly on launch safety. A Lifecycle Mission Safety Framework provides a new heuristic to guide system designers, mission planners, regulators, and international law for safety across the broad range of space nuclear applications. It expands safety goals beyond protection of the terrestrial population to workers and astronauts, as well as to activities in orbital space and planetary surfaces. By defining mission phases and identifying safety considerations in each, this framework provides for proactive identification and management of risk.

In the automotive industry, the importance of systems is increasing, and systems become more complex and larger. It is essential to ensure safety of vehicles which has complex and large systems. With the increase in cybersecurity risks due to systemization and connectivity of cars, and the evolution of automated driving technology, it is essential to ensure the safety of connected and automated driving vehicles. In accordance with this automotive industry's changing context, the three standards have come out. Those are ISO 26262 on Functional Safety, ISO/SAE 21434 on Cybersecurity, and ISO 21448 on Safety Of The Intended Functionality related to automated driving. This paper describes the approach of integrated management of Functional Safety, Cybersecurity and Safety of the intended functionality.