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Abstract This paper aims to present the lessons learned in 20 years of application of the SCE (Systems Concurrent Engineering) approach that evolved over the last 20 years being applied to the development of more than 200 complex system solutions. SCE is an approach to the integrated development of complex systems that applies the systems engineering process, simultaneously, to the product elements of a system solution as well as for the service elements of the system solution, recursively, at every layer of the system solution breakdown structure. The approach was born as the application of the requirements, functional and physical analysis processes to the simultaneous development of a product, its life cycle processes and their performing organizations, at every layer of the product breakdown structure. The continuous application of the approach up to 2010, showed the need to include a stakeholder analysis step, to acknowledge that the solution was comprised of product and organization elements (processes were, in fact, the functions of products and organizations), that a mission layer should be added at the top of the product breakdown structure and that the notion of circumstances should be added to the traditional notion of scenarios. With the increasing use of the approach for system of systems conception and development such as those involving multi-spacecraft solutions, the mission layer needed to be extended to include other life cycle processes (besides the operations processes) concept of service and system service architecture. This requires the development of a system solution breakdown structure that will guide the development of the overall solution. For multi-spacecraft solutions, for example, it is necessary to conceive and architect testing, launching and decommissioning services as early as operations. Also, going into more detail in the approach, modes can be derived from circumstances, interface states and internal states of the system and not only from circumstances, as initially established in the approach. These lessons to be presented were learned during the development of: 1) the Brazilian Strategic Program for Space Systems (PESE) and; 2) the TIM Project (Telematics International Mission), a satellite formation with contributions from many regions in the world. Highlights • The system solution contains product and service elements. • Concept of service/service architecture are developed for each life cycle scenario. • Analysis are performed simultaneously for product and service elements. • Circumstances refer to the states of the elements in the environment. • Modes are from circumstances and, functional and implementation hazard analysis. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents an exploration strategy for human missions beyond Low Earth Orbit (LEO) and the Moon that combines the best features of human and robotic spaceflight. This “Human Exploration using Real-time Robotic Operations” (HERRO) strategy refrains from placing humans on the surfaces of the Moon and Mars in the near-term. Rather, it focuses on sending piloted spacecraft and crews into orbit around Mars and other exploration targets of interest, and conducting astronaut exploration of the surfaces using telerobots and remotely-controlled systems. By eliminating the significant communications delay or “latency” with Earth due to the speed of light limit, teleoperation provides scientists real-time control of rovers and other sophisticated instruments. This in effect gives them a “virtual presence” on planetary surfaces, and thus expands the scientific return at these destinations. HERRO mitigates several of the major issues that have hindered the progress of human spaceflight beyond Low Earth Orbit (LEO) by: (1) broadening the range of destinations for near-term human missions; (2) reducing cost and risk through less complexity and fewer man-rated elements; (3) offering benefits of human-equivalent in-situ cognition, decision-making and field-work on planetary bodies; (4) providing a simpler approach to returning samples from Mars and planetary surfaces; and (5) facilitating opportunities for international collaboration through contribution of diverse robotic systems. HERRO provides a firm justification for human spaceflight—one that expands the near-term capabilities of scientific exploration while providing the space transportation infrastructure needed for eventual human landings in the future. [Copyright &y& Elsevier]

Abstract: Nanosatellite constellations at low Earth orbits represent a cost-efficient way for the accomplishment of Earth and space observation tasks. With the growing complexity of the exploration tasks, the amount of science data is expected to increase. For data download purposes efficient communication strategies must be adopted. The available power of a single nanosatellite spacecraft is limited by the small area of solar arrays. The communications equipment consumes a substantial amount of power. A constellation of nanosatellites allows to share resources efficiently, assigning major tasks to different spacecrafts. Within the constellation, a dedicated spacecraft which acts as data relay, monitoring and controlling inter-satellite communications is advantageous. This allows all other satellites to reuse the energy saved by implementing low-energy consuming communications links between the satellites. With this approach, taking advantage of scheduled communication contacts, the overall system performance can be maximized. For the envisaged data relay scenario, the adoption of advanced communication protocol concepts is required. This paper presents innovative solutions for the fulfilment of the described communications tasks. After an investigation of the system requirements, strategies for the interconnection of the spacecrafts for the creation of a small constellation network are provided. Suitable transport protocol implementations are investigated and efficient store-and-forward concepts are proposed. A communication architecture for the usage of a data relay satellite within the constellation is presented, describing the role of the different nodes in the network. [ABSTRACT FROM AUTHOR]

Abstract: This paper discusses the role of human being in space, his/her functions and responsibility during space flights beyond the Earth orbit. The relationship of the “Human”, “Machine” and the “Earth” as basic elements of the control and decision-making loop is analyzed to provide maximum efficiency of such complex system. [ABSTRACT FROM AUTHOR]

Abstract: Dawn launched in September 2007 on a mission to orbit main belt asteroids (4) Vesta in 2011–2012 and (1) Ceres in 2015. The mission is enabled by an ion propulsion system, which will be operated for the majority of the interplanetary cruise. Following 10.5 months of thrusting that concluded in October 2008, the spacecraft began a period of optimal coast that ended in June 2009. A Mars gravity assist in February 2009 provided an effective Δv of 2.6km/s. The mission flexibility afforded by the use of ion propulsion provided relatively simple targeting at Mars. Additional engineering activities were conducted during the coast period after Mars, including loading new software into the spacecraft''s central computer. This paper describe the progress of the mission, including the approach to Mars, the encounter itself, special activities conducted prior to the resumption of ion thrusting, and the continuation toward Vesta. [Copyright &y& Elsevier]

Abstract: “Space tourism” denotes any commercial activity that offers customers direct or indirect experience with space travel. Various models for space tourism activities exist including the use of an aircraft and/or spacecraft. The paper surveys some of the most important legal aspects relevant to space tourism activities, such as, the delimitation of airspace and outer space, the applicable legal regime and the definition of aircraft and space object, authorization, registration, liability, as well as the legal status of space tourists. [Copyright &y& Elsevier]

Abstract: The Space Systems Research Laboratory (SSRL) at Saint Louis University is developing SLUCUBE nanosatellite as part of the space mission design program. The objective of the mission is to demonstrate space capability of high performance nanosatellite components that has been developed at SSRL for the past three years. The objective of the program is to provide extremely low-cost and rapid access to space for scientists and commercial exploitation using commercial-off-the-shelf components. SLUCUBE is a double CubeSat with dimensions 10×10×20cm and a mass of 2kg. This nanosatellite features suite of technology demonstration components to enlarge the capability of space mission for such class of spacecrafts. The primary mission of SLUCUBE is to test and demonstrate several enabling technologies by flying a number of university developed high performance components. This paper describes the new developed technologies by providing details of specific components developed along with the R&D efforts and laboratory facilities. A brief discussion about the student involvement and educational benefits will also be presented. [Copyright &y& Elsevier]

Abstract: Upcoming space missions utilizing hyperspectral or other high-resolution sensors will generate a vast amount of data in orbit. The average communication duration between a spacecraft in low Earth orbit (LEO) to a dedicated ground station is short and in addition, due to the high amount of data to be transferred at link times, a high-performance communication system on board of the satellite is indispensable. A solution that provides longer acquisition times with the ground station is to employ a high data-rate inter-satellite link to a geostationary relay satellite, which requires a flat, compact, steerable, light-weight yet robust antenna. Such an antenna system (antenna module plus pointing module) was developed for S-Band at the Institute of Astronautics (Technische Universität München), in cooperation with German space companies, research institutes and the German Aerospace Center (DLR). Its successful operation via the geostationary relay satellite Artemis was demonstrated in cooperation with ESA in 2007. This paper describes the evaluation of an antenna system in the Ka-Band, as a successor to be developed in the next two years for high data rates and the various applications of such an antenna system. [Copyright &y& Elsevier]

Abstract: An algorithm for on-board planning of sub-orbital entry trajectories is presented. For entry vehicles with low lift-to-drag ratios and entering entry flight at sub-orbital speeds, this algorithm fills a gap left in a recently developed methodology for on-board generation of three-degree-of-freedom (3DOF) entry trajectories. The algorithm developed in this paper is able to reliably generate a 3DOF feasible sub-orbital entry trajectory in a time frame compatible with on-board environment. The combination of this algorithm and an algorithm recently developed for orbital entry missions provides the capability for full-envelope autonomous adaptive entry guidance. The current algorithm is validated by extensive high fidelity simulations using a sub-orbital reusable launch vehicle model and difficult mission scenarios including failures and aborts. [Copyright &y& Elsevier]