The results of an observation campaign devoted to the determination of the rotational state of uncontrolled disposed upper stages by ground-based optical observations are presented. The photometric analysis is performed to extract light curves from photographs obtained by a camera based on charge-coupled devices. The rotation-axis direction and rotation period are determined comparing measurements with theoretical predictions obtained in the simplifying assumption of cylindrical diffusely reflecting cylinders. The angular speed is evaluated by the light-curve period. The direction of rotation axis is evaluated by measuring the difference between the maximum and minimum apparent magnitude of disposed upper stages. This evaluation can be performed from a single observing site by combining measurements collected during a suitable observation time span. The results achieved for two orbiting objects are reported showing a good agreement between determinations obtained in completely different observation geometries

Besides large-scale space missions, the spread of CubeSats for a variety of applications is increasingly requiring the development of systematic approaches for risk management. Being these applications are based on components with low TRL (Technology Readiness Level) or with limited performance data, it is required to define approaches which ensure a systematic perspective. This paper aims to present a reliability engineering approach based on FMECA (Failure Mode, Effects, and Criticality Analysis) to manage CubeSat reliability data and prioritize criticalities early in the design phase. The approach firstly proposes an alpha-numeric coding system to support the identification and labeling of failure modes for typical CubeSats’ items. Subsequently, each FMECA coefficient (i.e., Severity, Occurrence, Detectability) has been linked to the CubeSat’s structural properties, reducing subjectivity by means of techno-centric proxy indicators. The approach has been validated in the design phases of a 6-Units university CubeSat for the observation of M-Dwarf stars and binary systems. The performed analysis supported the design process and allowed to identify the major criticalities of the CubeSat design, as demonstrated in the extended case study included in the paper. The formalized method could be applied to design procedures for nano-satellites, as well as being expanded for research and development in a variety of space missions.

This paper deals with the design, manufacturing, and test of a three-axis magnetic field simulator for space applications. The main aim of this simulator is to reproduce the orbital magnetic field conditions in a definite volume. The simulator makes it possible to carry out the ground calibration campaign of the satellite magnetic sensors and can be used in attitude control system simulations that exploit "hardware in the loop" devices. An overview of the mechanical and electronics design of the system is given; the mathematical model of the expected field is also discussed, achieving design constraints to get the largest homogeneous magnetic field volume. Moreover, test campaign results regarding magnetic field homogeneity are depicted and compared with those expected in theory.