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On-orbit servicing and on-orbit assembly represent very appealing mission concepts that could facilitate the exploitation of the space environment. Autonomy is a critical requirement for systems aimed at the execution of these operations. The development of enabling technologies for this type of missions is a focal research topic for the global space community. The AUTOMA project (University of Padua, Italy) aims at the development of technologies to enable the on-orbit assembly of a standardized modular unit by means of a robotic arm. The goal is the development of a capture interface, composed of a gripper mechanism and a suite of close-range navigation sensors (a navcam, four time-of-flight sensors, two custom matrix sensors based on a set of phototransistors), and the mock-up of a modular assembly unit. The paper prevalently focuses on the conspicuous series of tests that has been performed at subsystem level for the characterization of the two custom matrix sensors, both in terms of their resolution and range of application. In particular, the test campaign has proven how the in-plane matrix sensor provides information about lateral misalignment and relative distance with a resolution of a few millimetres while the roll matrix sensor provides information about the angular roll misalignment with a resolution dependent on the distance between the two bodies. In addition, an analytical relation for the computation of the relative distance through the information provided by the in-plane matrix has been investigated. • Capture interface composed of a gripper mechanism and a suite of close-range navigation sensors. • Design of a standardized unit mock-up for modular assembly. • Custom sensors based on a matrix of phototransistors activated by an infrared LED beacon counterpart. • Testing campaign aimed at the characterization of the custom matrix sensors. • Analysis of a relation for the retrieval of the relative distance based on the number of phototransistors activated. [ABSTRACT FROM AUTHOR]

Abstract The ROBEX (Robotic Exploration of Extreme Environments) alliance, as formed by the German Helmholtz association, aims to explore synergies and bring together technological challenges and scientific questions between two, up to now unrelated, fields: space and deep sea. The final goal of the alliance targets field tests for available and newly developed instrumentation for the deep sea and on a terrestrial lunar analogue. In this regard, two different test campaigns were conducted, one in the area of Svalbard, Norway and one on mount Etna in Sicily, Italy. The volcano environment served as a lunar analogue, enabling seismic scientific experiments and testing of robotic mobility algorithms. The complete field mission infrastructure consists of a stationary lander, a mobile element and instrument carriers. The modular instrument carrier, commonly referred as Remote Unit (RU), was developed accounting for two different mass requirements: 3 kg (RU3) and 10 kg (RU10). While developed in the frame of ROBEX resumes the idea of a lightweight instrument carrier as developed for the MASCOT (Mobile Asteroid surface scout) mission. The RU houses the instrument, shelters it and provides all essential support functions such as rudimentary thermal control (via foil covering), power provision, data acquisition and handling and data transmission to the control centre. This paper presents theoretical and experimental results of the RU3 power subsystem analysis during the mount Etna field campaign. Drawing upon this analysis, necessary adjustments and revisions to further develop the system towards a more power efficient structure for terrestrial and extraterrestrial usage can be concluded. Highlights • RU suitable for harsh environments-space analog demonstration missions. • Test Data confirmed theoretical estimations for power management and consumption. • RU suitable for planetary exploration investigated (exemplary Moon application). • RU capable of surviving a complete lunar day when outfitted with photovoltaic cells. • A qualitative outlook on needed adaptations, focused on mass savings was considered. [ABSTRACT FROM AUTHOR]

Abstract: The paper deals with the design and realization of a hexapod rover prototype completely manufactured by students and researchers of the Space Robotics Group of the II Faculty of Engineering of the University of Bologna “ALMA MATER”. The rover project has been developed for didactical purposes, with the aim of involving students in practical, hands-on education, pushing them to face real problems and to put in practice what they have learnt in theory during regular courses. The work done is described in the paper, highlighting its potential to test different solutions in autonomous navigation systems: low-cost sensors, innovative algorithms and different step procedures. Moreover, the mechanical and electronic solutions adopted for leg design, main controller, and remote control are discussed and depicted in the paper. [Copyright &y& Elsevier]

Abstract: SpacE Exploration and Development Systems (SEEDS) initiative originated from Politecnico di Torino and Thales Alenia Space Italy in 2005. It aimed at establishing a postgraduate international master course in space exploration and development systems to offer an opportunity to young engineers to get prepared for the future of Europe in space exploration. SEEDS project has been shared with Supaero Toulouse in France and with University of Bremen (together with the Center of Applied Space Technology and Microgravity, ZARM) in Germany. SEEDS course comprises of two different steps in sequence: an initial learning phase and a project work phase. The distinguishing feature of SEEDS is without any doubt the project work phase, which includes the preparatory work and the conceptual design activities, performed in three European sites to develop a limited number of building blocks identified during the preparatory work. The first year of activity started in November 2005. Five years of activities have passed since then and five project works have been successfully completed, dealing with various space exploration themes. The paper focuses on the description of SEEDS master course, in terms of master course structure, applied methodology and students team organization, and on the main results achieved, in terms of project work activities and development of future space workforce. The positive experience of five years of SEEDS is brought to evidence and lessons learned are discussed in view of SEEDS continuation. [Copyright &y& Elsevier]

Abstract: The Medicina Radioastronomical Station is located nearby Bologna, in Italy. It consists of two receiving antennas currently dedicated to the astronomical research at radio frequencies. The 32m diameter parabolic dish performs observations from 1.4 to 22GHz whereas the Northern Cross (a 30.000m2 wide T-shaped array transit antenna) works at 408MHz. So far SETI observations have been performed using a SERENDIP IV high resolution spectrometer connected to the parabolic antenna. Data acquisition were performed meanwhile the antenna was employed in ordinary astronomical observations (piggy-back mode). An innovative method to search for possible extraterrestrial signals could be provided by using the UHF Northern Cross transit telescope. In this paper observational modalities and the required technological set-up are investigated. [Copyright &y& Elsevier]

Abstract: PRISMA (PRecursore IperSpettrale della Missione Applicativa) hyperspectral instrument is an advanced hyperspectral sensor including a panchromatic camera at medium resolution. The instrument is the focus of the new Earth observation mission that a consortium of Italian companies has started developing under contract of Italian Space Agency. Key features of the instrument are the very high requirement for signal-to-noise and the high quality of data that have to be provided. To meet these demanding figures the optical system has been based on a high transmittance optical system, including a single mirror telescope and two prism spectrometers based on an innovative concept to minimize number of optical elements, while high performance detectors have been chosen for the photon detection. To provide the required data quality for the entire mission lifetime an accurate calibration unit (radiometric and spectral) will be included in the instrument optomechanical assembly. The thermo-mechanical design of the instrument is based on innovative concepts, considering that the use of prism spectrometers implies a tight control of temperature variations to guarantee the stability of all instrument features once in orbit. The presented paper describes the concepts and design principle of the optomechanical assembly of the instrument, at the present status of development. [Copyright &y& Elsevier]

Abstract: The first dropped transonic flight test (DTFT) of the USV Program, performed with Castor, the first of the two spacecrafts developed within the USV Program, was performed on Saturday 24th February 2007, from Tortolì Airport in Sardinia. At 8:30 a.m. the 340000m3 stratospheric balloon lifted off from the East coast of Sardinia, bringing the flying test bed (FTB) up to 20.2km before release within the isolated sea polygon controlled by Italian air force test range in Salto di Quirra (PISQ). The mission ended at 10:30 a.m. with the splash-down of the space vehicle. The flight itself was very good, with a nose-up manoeuvre under transonic conditions, reaching a maximum Mach as high as 1.08. The mission target was completely achieved as some 2 million measures were taken related to flight data, housekeeping, as well as 500 aerodynamic and structural experimental sensors. Unfortunately, the vehicle has been damaged more than expected during splash-down. Many national and international institutions and industries contributed to the mission carrying out, under the supervision and technical guide of CIRA: Italian Space Agency, Italian Air Force, Italian Navy, Italian Civil Aviation Authority, Italian Company for Air Navigation Services, Port Authorities, European Space Agency, Techno System Dev., Vitrociset, Carlo Gavazzi Space, Space Software Italia, Alcatel Alenia Space Italy, ISL-Altran Group. The paper reports the actual status of post-flight data analysis. [Copyright &y& Elsevier]

Abstract: UNISAT-4 is the fourth educational microsatellite, completely designed and built by students and professors of the research group GAUSS (Gruppo di Astrodinamica dell’Università degli Studi “la Sapienza”) at the Scuola di Ingegneria Aerospaziale of University of Rome “La Sapienza”. The spacecraft is stabilized using a passive magnetic attitude stabilization system, based on a permanent magnet and an energy dissipation system, which consists of magnetic hysteresis rods. The main features of passive magnetic stabilization are simplicity and reliability. However, sizing the system parameters, predicting the in-orbit performance and obtainable accuracy of passive magnetic stabilization systems is not trivial. The main problem in the system design is accurate modeling of the hysteresis rods magnetization and the evaluation of the rods magnetic parameters, such as apparent permeability, remanence and coercitive force, which are considerably affected by the rods’ manufacturing technological process. In this paper the design and ground test of the UNISAT-4 magnetic attitude stabilization system is described. A method to experimentally determine the hysteresis rod parameters is described and an accurate model of the satellite dynamics is obtained, based on the results of the measurements. One of the main design parameters is the number of hysteresis rods necessary to obtain satellite stabilization. Numerical simulations for two hysteresis rods per axis and eight hysteresis rods per axis are discussed, showing that the satellite stabilizes in about 14 days, with a residual oscillation amplitude of less than 10°, if eight rods are used. [Copyright &y& Elsevier]

Abstract: A new plasma wind tunnel is under construction at the Italian Aerospace Research Centre (CIRA) located at Capua. It is named GHIBLI and the plasma is generated by a segmented arc heater whose power is about 2MW. Such a new facility will be able to perform test campaigns on models up to 80mm in diameter, and may be used to develop researches in the aerospace field of the hypersonic plasma flows from the reentry technologies to the validation of CFD codes for the theoretical predictions of aerothermodynamic phenomena. Target of the present paper is the presentation of results obtained by means of CFD simulation by using the well-known FLUENT code, Such a code has been used to simulate the aerothermodynamic field inside the conical nozzle of the facility to obtain some analytical correlations (fits) between the main aerodynamic parameters at the nozzle exit, such as the Mach number, flow density, mass flow rate, etc. and the reservoir conditions inside the arc heater column, total pressure and total enthalpy. Such fits allow fast theoretical prediction of the facility operation parameters for given reservoir conditions. [Copyright &y& Elsevier]

Abstract: SETI-Italia is the Italian national SETI Program. It is run as a part of the Italian Bioastronomy Project, by IRA (Istituto di Radioastronomia) a subsidiary of the Istituto Nazionale di Astrofisica. At the moment, Italy is the only European country conducting a continuous SETI “listening” program, while occasional SETI searches may be conducted in France and the Ukraine. Outside Europe, continuous SETI programs are conducted in the USA, Australia and Argentina. The SETI-Italia activities started early in 1998 with a Serendip IV system connected in piggy-back mode to the Medicina VLBI 32-m antenna dish. In the years 2002/2003, considerable efforts were devoted to set up a fast computational system capable of computing the KLT (Karhunen–Loève transform). This is a virtually new mathematical procedure in SETI, and is much more general than the FFT. It can search for the presence of signals both narrow-band and wide-band embedded in noise both coloured and white. The mathematical features the KLT have already been described in this Conference by Claudio Maccone [Innovative SETI by the KLT, Pešek Lecture 2003, paper # IAA.9.1.01 presented in Bremen, in this 2003 International Astronautical Congress ; Telecommunications, KLT and Relativity, vol. 1, IPI Press, Colorado Springs, CO, 1994, ISBN #1-880930-04-8 .]. Our software implementation of the KLT follows these lines and also is indebted to some basic ideas put forward by Robert S. Dixon [On the detection of unknown signals, in: G. Seth Shostak (Ed.), Third Decennial US–USSR Conference on SETI, Astronomical Society of the Pacific Conference Series, vol. 47, 1993, pp. 128–140] of the Ohio State Radio Observatory as early as 1993. [Copyright &y& Elsevier]

Abstract: How is it possible to recognize ETI signals coming from exoplanets? This is one of the questions that SETI researchers must answer. In early 1998, the Italian SETI program [S. Montebugnoli, et al., SETItalia, A new era in bioastronomy, ASP Conference Series, vol. 213, 2000, pp. 501–504.] started in Medicina with the installation of the Serendip IV 24Million Channel digital spectrometer. This system daily acquires a huge quantity of data to be processed off line, in order to detect possible ETI signals. The programs devoted to this topic are collectively called SALVE 2. Here a natural evolution of a previous effort is presented, which was based on a simple Hough transform and was limited to the detection of short linear tracks in the join time frequency matrix (JTFM) stored by SIV. The new generalized Hough algorithm allows us to detect the sinusoidal tracks by the transformation of the JTF bidimensional Cartesian space , in the generalized Hough quadridimensional space, where the main vectors are the sine parameters amplitude, frequency, phase and offset. At the end of the paper some results, obtained with the computation of real and simulated JTFM, are shown. [Copyright &y& Elsevier]