Conventional magnetic attitude control methodologies require several orbital periods to accomplish the required attitude maneuvers due to the existence of an uncontrollable axis, namely the local Earth’s magnetic field vector. Since in some attitude maneuver missions the elapsed time is of critical importance, those time-consuming controllers are not satisfactory and we need a much faster contr...

Maneuver detection is a very important task for maintaining the catalog of the orbital objects and space situational awareness. This paper mainly focuses on the typical maneuver scenario, where space objects only perform tangential orbital maneuvers during a relative long gap. Particularly, only two classical and commonly applied orbital transition manners are considered, i.e. the twice tangent...

The frequent maneuvering of BeiDou Geostationary Orbit (GEO) and Inclined Geosynchronous Orbit (IGSO) satellites affects the availability of real-time orbit, and decreases the accuracy and performance of positioning, navigation and time (PNT) services. BeiDou satellite maneuver information cannot be obtained by common users. BeiDou broadcast ephemeris is the only indicator of the health status ...

To perform the orbital maneuvers, a software that calculates an optimal maneuver is developed. This method will be used as a reference for comparison and analises of the suboptimal methods to be used on board. This method id based on an analytical development that generate equations that can be computed in a shorter time, allowing real time applications. Key-Words: Orbital maneuvers, low thrust...

With overcrowding threatening the safety of Earth’s orbital environment, methods for tracking and understanding the motions of objects in orbit have become very important. This paper details an estimation algorithm that incorporates optimal control for the purposes of Maneuver Detection and Reconstruction. In this context, maneuver refers to any unmodeled acceleration: active spacecraft thrusti...

ABSTRACT: The aim of this paper was to identify, for a specific maneuver, the optimal combination between the trajectory and the associated heat shield configuration, namely the locations and thicknesses of the ablative and reusable zones, that maximize the allowable payload mass for a spacecraft. The analysis is conducted by considering the coupling between the trajectory’s dynamics and the he...

Orbital venous varices can be a perplexing imaging problem, as they typically are expanded only during periods of venous hypertension, which is transmitted cephalad owing to the lack of valves in the internal jugular veins [1]. When venous pressure is not elevated , orbital varices may collapse and be undetectable on routine imaging studies, such as axial CT scans of the orbit. A provocative te...