Ricerc@Sapienza

Multistage launch vehicles are commonly employed to place spacecraft in their operational orbits. Several characteristics, i.e. mass distribution and time variation, propulsion, and aerodynamics, affect the overall performance of the ascent vehicle of interest. Thus, it is apparent that accurate modeling is a central issue and an essential prerequisite for trajectory optimization. This research uses the Scout, a launch vehicle of reduced size used in the past, as the reference multistage rocket.

In recent years, manifold dynamics has assumed an increasing relevance for analysis and design of low-energy missions, both in the Earth-Moon system and in alternative multibody environments, and several space missions have already taken advantage of the results of the related studies. Recent efforts have been devoted to developing a suitable representation for the manifolds, which would be extremely useful for mission analysis and optimization.

The Small Mars System is a proposed mission to Mars. Funded by the European Space Agency, the project has successfully completed Phase 0. The contractor is ALI S.c.a.r.l., and the study team includes the University of Naples “Federico II”, the Astronomical Observatory of Capodimonte and the Space Studies Institute of Catalonia. The objectives of the mission are both technological and scientific, and will be achieved by delivering a small Mars lander carrying a dust particle analyser and an aerial drone.

A novel approach for minimum-time reconfiguration of satellite formations is proposed considering the perturbation forces as control variables. Planning appropriate attitude maneuvers for each satellite, the atmospheric drag and of the solar radiation pressure are properly controlled, and the formation is given the appropriate inputs to achieve the imposed reconfiguration. Limits and advantages of the presented maneuvers are examined considering low Earth orbits, medium Earth orbits, and geostationary orbits.

Distributed inverse synthetic aperture radar (ISAR) exploits the data acquired by multiple radar sensors carried by multiple platforms working in formation to increase the cross range resolution with respect to the value achievable by single platform systems. In this frame, the paper addresses the problem of the estimation of the ship dynamics, i.e., yaw, pitch, and roll rotation motions, exploiting the signals collected by such multiplatform radar imaging systems providing angular diversity in order to enable the focusing of the distributed ISAR images.

This paper introduces innovative detection schemes for Forward Scatter Radar (FSR) based on the GLRT (Generalized Likelihood Ratio Test) for both cases, where a fixed threshold can be used and where a fully adaptive CFAR scheme is desired. The detection performance of the newly proposed detectors is characterized analytically and compared to the performance of the standard detection scheme. This shows that the new detectors always outperform the standard FSR detector.

The forward scatter radar (FSR) configuration is especially appealing for the detection of low-observable targets since it provides well-known properties for the radar cross section, which includes enhancements with respect to the monostatic and/or moderate bistatic configurations, aswell as robustness to the target material and detailed geometrical characteristics.

The objective of the paper is to propose and evaluate the performance of a TTEthernet network architecture applied in small launchers in order to interconnect the terminals (on-board computer, telemetry apparatus, Inertial Reference System,...) performing the Guide, Navigation and Control (GNC) operations and producing/receiving telemetry traffic. The work described in the paper was been funded by Italian Space Agency (ASI) within the research agreement titled 'Advanced Avionic Architecture (AAA)'.

We present the first prototype of a new concept grasping device whose overall size has been reduced as much as permitted by a new NEMS-based fabrication procedure. The fabrication processes used are compatible with rigid or flexible substrates and the materials employed are biocompatible and chemically inert. The jaws lumen size is adequate to the mechanical manipulation of micro- and sub-microscaled objects and organic matter like bacteria.