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The partial space elevator is a space transportation system that conveys cargo by a climber moving along the tether that connects the main satellite and the end body. This work proposed a novel prescribed performance based dual-loop control strategy for configuration keeping of the partial space elevator in cargo transportation. The control loop I controls the libration angle of the climber by a newly proposed prescribed performance control law to track the desired state with bounded performance. The Lyapunov stability of the control law is proved analytically. Control loop II stabilizes the overall configuration of the PSE by applying thrust and deploying/retrieving the tether simultaneously at the end body. To enforce the constraint that the total tether length is unchanged at the end of transportation, an event-triggered loaning control algorithm is proposed to further improve the Control loop II. Numerical simulations validate the prescribed performance based dual-loop control strategy. The results show that the stable configuration of the PSE is kept effectively with no libration motion in the period of cargo transportation.

Space Rider is the European program proposed to develop an affordable and sustainable reusable space transportation system to enable access to and return from space. To procure a safe and accurate ...

The problem of increasing the efficiency of transport operations in space is currently coming to the fore. In the context of this problem, we investigated the possibility of developing a space transportation system including a chemical upper stage and an electric propulsion transport module capable of performing a specified range of space maneuvers. Electric propulsion module design was carried out for a given range of target orbits and payload mass with the provision of restrictions on the flight time. Calculation of the ballistic characteristics of the flight is performed and an optimal program of placing a low-thrust vehicle into orbit is defined. A procedure for defining the design parameters of a space transportation system and its conceptual design is proposed. The conceptual design of the space transportation system and the electric propulsion module were formed in the PTC Creo Parametric environment. On the basis of the results of the work, it can be concluded that it is possible to create a space transportation system with given parameters.

Laser propulsion is a space transportation system that obtains thrust from a laser beam that is transmitted from the ground as an energy source. In this study, we evaluated the launch performances of two types of laser propulsion systems in a circular orbit at an altitude of 500 km. One propulsion used the heating system of the laser-sustained plasma (LSP) type, and the other propulsion had the heating system of the porous-carbon heat exchange (hereinafter PHX) type. Assuming a laser power of 500 kW, which is the maximum laser power that is commercially available, the payload masses were estimated to be 0.679 and 0.640 kg for the LSP and PHX systems, respectively. This result shows that the laser power level that is currently available enables the launch of a picosatellite. The laser power values required to launch a nanosatellite less than 10 kg were estimated to be 6.8 and 6.4 MW for the LSP and PHX systems, respectively. Finally, the launch cost was estimated as a function of the number of launches. Our results show that, when the picosatellite was launched 1000 times, the launch cost became comparable with that of a conventional nanosatellite launch. Subsequently, the launch cost decreased to one-twentieth the cost of a conventional chemical rocket.

The aim of this work is a technical review about Quartz Crystal Microbalance (QCM) sensors used in space missions, i.e. Space Shuttle flights, i.e. NASA Space Transportation System (NASA STS) and satellite missions, that aimed at monitoring the contamination generated by outgassing processes of materials onboard satellites and sensitive payloads. The contamination processes are critical for scientific instrumentation (e.g. optics, telescopes, detectors) because scientific measurements and performances can be jeopardized or worsened by uncontrolled contamination. This issue has been addressed by the space agencies, e.g. NASA, ESA and JAXA that have implemented many different studies to monitor the material outgassing and degradation in space environment. During the past years, the QCM sensors have become the baseline solution for measuring material outgassing and characterizing the on-orbit contamination environment. This work summarizes the main QCM applications in Space and their findings, providing an overview of the sensors’ performances in terms of stability, power, data rate, measurement accuracy and resolution. Different QCM technologies will be compared highlighting the advantages of their use for the next space missions and instrumentations that require an accurate monitoring of contamination environment. In particular, due to more severe contamination requirements for next payloads and instrumentations, QCM sensors would be useful to estimate the cleanliness degree by evaluating the induced contamination and degradation on sensitive instrumentations.

This paper studies the feasibility of the single-stage-to-orbit (SSTO) rocket with an initial nonzero velocity given by the auxiliary electromagnetic launch (EML) system. First, the development his...

The Lunar Space Tug is a sustainable transportation system able to rendezvous with a target body in Low Earth Orbits environment, assess its current position, attitude and operational status, capture the target and move it to the Cislunar space where the Lunar Orbital Platform-Gateway will be settled. Thanks to the adoption of an electric Propulsion Subsystem based of Hall Effect Thruster clusters, the Lunar Space Tug can save fuel to the detriment of much longer transfer time to deliver the unmanned cargo to the cislunar Gateway. Since the Lunar Space Tug has been conceived to be reusable, one of the main issue is related to the on-orbit refueling to sustain the Lunar Space Tug during its operational lifetime. Each mission scenario shall take into account the effects related to refueling operations according to mission requirements and constraints. Considering the whole mission scenario in which the Lunar Space Tug will operate, this paper focuses on mission analysis and conceptual system design, including typical systems budgets, like transfer duration, Δv, mass and power. Moreover, according to the transfer duration and the needs of the Lunar Orbital Platform-Gateway, a preliminary trade-off analysis has been accomplished to investigate the possibility of using a fleet of Lunar Space Tug instead of a single tug, taking onto account safety, reliability, costs and operations issues. The identified optimal configuration is then compared with the current reference option, i.e. the NASA Space Launch System adopted as cislunar delivery vehicle.

At present, the world has developed to a new stage of large-scale access to space, which has put forward higher requirements for the development of space transportation. Facing the historical mission of building a space power, focusing on the construction of the China’s space transportation system, this paper studied the development situation of the space transportation system in the world, summarized the development status of the China’s space transportation, combined with future development requirements, and put forward prospects for the future development of the China’s space transportation system.

“John, we can’t do more from the launch team than say, we wish you an awful lot of luck,” radioed Launch Director George Page from the Launch Control Center (LCC) at the Kennedy Space Center (KSC) in Florida, a few minutes before 7 a.m. EDT on Sunday, 12 April 1981. “We are with you one thousand percent and we are awful proud to have been a part of it. Good luck, gentlemen.” Out on historic Pad 39A, Columbia – bolted like an ungainly butterfly onto a pure-white External Tank (ET) and twin Solid Rocket Boosters (SRBs) – stood ready to embark on the Space Transportation System’s first mission, a two-day test flight designated STS-1. Commander John Young responded with thanks. Next to him was pilot Bob Crippen. Both men had been training for STS-1 for three years and, if not for a last-minute computer malfunction, they might have launched two days earlier.

Space elevators are expected to change significantly the method of deployment of Earth-orbiting satellites, offering a more efficient and elegant approach than chemical rockets. A space elevator consists of one or more ribbons (tethers) stretching from the surface of the Earth to a counterweight located beyond the geosynchronous altitude. Before a full space elevator is deployed, it is likely that a partial space elevator will be deployed. One of the key requirements for the design of a space elevator is the understanding of its mechanics. This article discusses the statics and dynamics of space elevators.

We present a design lay-out diagram of the reusable space transportation system that consists of an aerospace transformed vehicle that is injected into an orbit by means of the first and second stages. Some starting configurations of such system with the first and second stages are considered.

This paper presents the very first steps of a methodology aimed at supporting the generation and update of technology roadmaps developed in close cooperation between Politecnico di Torino and the European Space Agency, here focusing on the map elements derivation and characterization in order to simplify the activities that will follow. Roadmapping activities are becoming crucial in several domains dealing with complex systems as well as an urgent demand of a rational process starting from the identification of Stakeholders and relative needs and leading the growth of technology readiness levels has been noticed. This research study seems to be suitable for application in the advanced transportation domain, especially in the aeronautical and aerospace sectors. In detail, this paper proposes a rational generation of a series of elements that can potentially be involved in the definition of technological roadmaps for re-entry space transportation systems. Indeed, today, there is an important momentum, at national and institutional level, on studying/developing demonstrators and/or experimental new vehicles and propulsion systems targeting different kinds of missions, all around the world but especially at European Space Agency level. After a brief overview of the major activities related to reusable space transportation system carried out in Europe, the paper focuses on the proposed Systems Engineering based methodology for the generation and combination of the main four pillars (i.e. elements) involved in a roadmap: i.e. Operational Capabilities, Technology Areas, Building Blocks and Mission Concepts. These elements will be derived, characterized and stored according to the future planning needs. The second part of the paper presents the application of this logical methodology to the selected case study, to derive, track and manage the previous pillars. The paper concludes anticipating the following steps that will lead to the technology roadmaps preparation based on the methodology described here. Moreover, the exploitation of a well-defined methodology can allow reaching optimal development strategy, minimizing costs and enhancing the public consensus with respect to space initiatives.

The method developed to avoid the complexity of solving the multipoint boundary value problem while optimizing interplanetary trajectories of the spacecraft with electric propulsion and a sequence of swing-bys is presented in the paper. This method is based on the use of the preliminary problem solutions for the impulsive trajectories. The preliminary problem analyzed at the first stage of the study is formulated so that the analysis and optimization of a particular flight path is considered as the unconstrained minimum in the space of the selectable parameters. The existing methods can effectively solve this problem and make it possible to identify rational flight paths (the sequence of swing-bys) to receive the initial approximation for the main characteristics of the flight path (dates, values of the hyperbolic excess velocity, etc.). These characteristics can be used to optimize the trajectory of the spacecraft with electric propulsion. The special feature of the work is the introduction of the second (intermediate) stage of the research. At this stage some characteristics of the analyzed flight path (e.g. dates of swing-bys) are fixed and the problem is formulated so that the trajectory of the spacecraft with electric propulsion is optimized on selected sites of the flight path. The end-to-end optimization is carried out at the third (final) stage of the research. The distinctive feature of this stage is the analysis of the full set of optimal conditions for the considered flight path. The analysis of the characteristics of the optimal flight trajectories to Jupiter with Earth, Venus and Mars swing-bys for the spacecraft with electric propulsion are presented. The paper shows that the spacecraft weighing more than 7150 kg can be delivered into the vicinity of Jupiter along the trajectory with two Earth swing-bys by use of the space transportation system based on the "Angara A5" rocket launcher, the chemical upper stage "KVTK" and the electric propulsion system with input electrical power of 100 kW.

To build a sustainable and affordable space transportation system for human space exploration, the design and deployment of space infrastructures are critical; one attractive and promising infrastructure system is the in-situ resource utilization (ISRU) system. The design analysis and trade studies for ISRU systems require the consideration of not only the design of the ISRU plant itself but also other infrastructure systems (e.g., storage, power) and various ISRU architecture options (e.g., resource, location, technology). This paper proposes a system-level space infrastructure and its logistics design optimization framework to perform architecture trade studies. A new space infrastructure logistics optimization problem formulation is proposed that considers infrastructure subsystems' internal interactions and their external synergistic effects with space logistics simultaneously. Since the full-size version of this proposed problem formulation can be computationally prohibitive, a new multi-fidelity optimization formulation is developed by varying the granularity of the commodity type definition over the network graph; this multi-fidelity formulation can find an approximation solution to the full-size problem computationally efficiently with little sacrifice in the solution quality. The proposed problem formulation and method are applied to a multi-mission lunar exploration campaign to demonstrate their values., 34 pages, 3 figures, a former version was presented at the AIAA Propulsion and Energy Forum 2019

Spaceplanes represent a new promising concept for space flight. A spaceplane is a reusable, safe, efficient and economical space transportation system that can generate lift during its atmospheric flight, analogously to an aircraft, and it is able to travel in space as a spacecraft. What makes spaceplanes so attractive is the possibility of reusing the system for more than one mission, and the flexibility that they allow in mission. The growing interest in hypersonic spaceplanes requires that these vehicles have adequate properties of safety of flight and ease of controllability in nominal and off-nominal conditions. From this it follows the need to study their flying qualities and controllability characteristics. The current thesis addresses the flying-quality and controllability analyses, together with the development of a control system capable of improving these properties. The analyses are conducted along the ascent and re-entry trajectory of a representative single-stage-to-orbit spaceplane, the Festip System Study concept 1. The stability, trim capabilities and flying qualities of the open-loop system are analysed by studying the eigenvalues and eigenvectors of the state matrix of the state-space model. Comparing the obtained results with the requirements specified in the military documents MIL-F-8785C and MIL-HDBK-1797 for subsonic vehicles, it is possible to conclude that the reference vehicle is dynamically unstable. Thus, the need for an advanced control system arises. One concept seems particularly interesting for this application: the adaptive control system, which is characterised by a low sensitivity to disturbances thanks to its adaptive gains. Not only the control system is design to be optimal in terms of integrated control error and effort, but also a robust design methodology is applied to identify a control design that is as insensitive as possible to uncertainties of the input and design parameters. The responses for both longitudinal and lateral control in nominal and off-nominal conditions are simulated and evaluated. It results that the system behaviour is strongly related to the control system performance. The robust and advanced control system is able to stabilise the vehicle with relatively low control effort and minimise the effect of disturbances, guaranteeing safety of flight and mission success.

In order to realize reusable winged sub-orbital transportation system, the Space Systems Laboratory, Kyushu Institute of Technology has worked in research, development, and flight test for winged rocket which is called “WIRES” (WInged REusable Sounding rocket) since 2005. Autonomous flight system is one of the most important research fields for space transportation system.

As the Reusable Launch Vehicle can reduce the launching cost, and improve the ability of Operationally Responsive Space (ORS), many aerospace powers in the world consider the Reusable Launch Vehicle as a main development tendency of space transportation system. Recently, Space Exploration Technologies Corporation (SpaceX), as the spokesman of private aerospace corporations, has attracted all the world’s attention to the Reusable Launch Vehicle. SpaceX has been developing technologies for rockets’ fully and rapid reusability, and several recovery tests have been conducted on technology-demonstrators and post-mission controlled-descent tests on Falcon 9 rockets’ first stages, both touchdown on the ocean platform and the land. On 22 December 2015, a Falcon 9 FT rocket of SpaceX, carrying 11 Orbcomm communications satellites, lifted off from Cape Canaveral. After cutoff and stage-separation, the Falcon 9s first stage flight back into the atmosphere and pulled off a powered landing on on Landing Zone 1, which is about 10 km far away from the Launch Site of SLC-40, settling to a smooth tail-first touchdown, making it a significant space “first”. After already celebrated a successful booster landing, SpaceX had decided to attempt a landing at sea on this flight despite available margins for a return to land. This decision was prompted by the need to master the landing sequence for sea-based recoveries which will be needed for about half of Falcon 9’s flights when lifting heavy satellites to high-energy orbits. On 8 April 2016, SpaceX’s Falcon 9 FT rocket, carrying CRS-8 Dragon cargo, lifted off from Cape Canaveral. The Falcon 9’s first stage has accomplished the first ever successful returning rocket on the Autonomous Spaceport Drone Ship (ASDS). This is considered a landmark accomplishment on the road to economical interplanetary and asteroid-to- planet space travel because it enables expensive launch vehicles to be reused. In this paper, based on the experiments of Falcon 9, and analyzing the main projects of the Reusable Launch Vehicle abroad in the past 60 years, the critical technologies will be researched and the results will provide references for the research of new type of space transportation systems.

This study presents a new guidance and control system using a constrained adaptive backstepping method for a space transportation system. In this method, the effects of input saturations by actuator dynamics (e.g. magnitude, rate and bandwidth) are considered to introduce the compensators on the basis of pseudo control hedging. The stability of the proposed entire system is guaranteed by the Lyapunov’ stability theorem. To confirm the realization and robustness of the proposed system, Monte Carlo simulations (MCSs) were performed. In addition, to obtain optimized control performance, a parameter optimization algorithm combined with the MCSs was introduced. Finally, automatic landing simulations using the six degrees-of-freedom nonlinear flight simulation model of the NASA’s Space Shuttle Orbiter were performed to verify the effectiveness of the proposed technique.

Designed for the launch and subsequent on-orbit maintenance by astronauts and the Space Shuttle, the Hubble Space Telescope presented a unique and challenging set of flight operations issues during six missions between 1990 and 2009. Starting with the launch in 1990 and for the following three servicing missions, the solar arrays represented an unanticipated and significant operational challenge for the crews and the flight operations teams. Modified first-generation solar arrays were installed on Servicing Mission 1 in 1993 to correct for a jitter introduced into the telescope’s control system by the design of the original solar arrays. However, although the jitter was improved, the modified solar arrays introduced additional issues for the second servicing mission, Space Transportation System 82, due to the existence of a significant static twist. New flight operations techniques had to be developed to monitor the condition and protect the integrity of the solar arrays. It was not known until after Hubb...

For space transportation systems used to place satellites in space, the launch rate fulfillment (turnover) and the launch delay reduction (avoid additional cost) are key parameters driving the launch cost. In addition, launching on-time is beneficial to the payload operator business model.

International audience; This paper presents the methodology used to preliminary design a future cost-effective air launch system for small satellites, studied in the frame of the H2020 ALTAIR project (Air Launch space Transportation using an Automated aircraft and an Innovative Rocket). This methodology relies on the use of design to cost associated with multidisciplinary design optimization (MDO) techniques. The particularity of this system is to use a reusable unmanned aircraft carrier designed specifically for the air-launch mission associated with an expendable, low cost, launch vehicle. The methodology used to design the space launch system relies on collaborative engineering between sub-system design tasks and sustained application of design-to-cost techniques and multidisciplinary design optimization strategies. Risk mitigation, cost savings, reliability and performances are major drivers in the development of the final system, leading to a delicate balance between technological innovation, low cost solutions and maturity level. The main difficulty for a design of a new vehicle is to establish a first feasible design, due to the sensitivity on the various design parameters. To ensure a good optimization of the vehicle satisfying design constraints, simplified models have been elaborated and combined in an optimization platform using di_erent optimization algorithms at different steps of the process (genetic, BFGS. . . ). The originality of the methodology put into place is to target cost-effectiveness at every levels of the design system: at sub-system level and also at system level through an integrated carrier/design optimization process, with the main coupling variables being the launcher release conditions. The paper provides the results obtained at the end of the final design loop of the system. Finally, the paper illustrates how this methodology can help and foster the design of new space launch vehicle to manage safety margins, reduce design duration and to achieve a low cost space system.

In this paper, a new concept for a distributed space transportation system is proposed and a corresponding decentralized cooperative control scheme is investigated. First, for a leaderless team of homogeneous space robots transporting a large object in orbit, a systematic control architecture that includes information flow is developed. Second, based on relative orbit dynamics, a rendezvous guidance law and a rigid formation control law are designed, and the necessary communication topology for the space robot team is discussed. Third, to guarantee the consensus of the motion of the large object with the robot team, both orbital maneuver control and attitude control for the large object are studied Emphasis is placed not on the attitude control law but on the force distribution problem, for which an algorithm exploiting a special property of trigonometric functions is proposed to transfer the necessary attitude control torque to the distributed forces. To support the above control method, an estimation of the motion of the formation center contributed by each robot in a decentralized manner is developed using a Kalman filter. Fourth, the robustness of the system to the failure of one robot is analyzed, and four effective typical fault response modes are proposed. Finally, numerical simulations validated the performance, robustness and practicability of the developed control scheme.