In an example embodiment, an attitude, orbit, and de-orbit control system (AODCS) for a satellite is provided. In an example embodiment, the AODCS system comprises one or more selectively retractable booms. The one or more selectively retractable booms are collectively configured to provide a selectively adjustable drag during de-orbiting of a satellite over a predefined de-orbiting time.

Disclosed is a magnetic-fluid momentum sphere, which is used for satellite attitude adjustment. The magnetic-fluid momentum sphere comprises stators and a spherical shell. The stators are classified into three groups, axes of the three groups of stators are orthogonal to each other, each group comprises two stators arranged symmetrically about the center of the spherical shell, and the inner surfaces of the stators are spherical surfaces. The spherical shell is formed by combining two hemispherical shells, the material of the spherical shell is a non-ferromagnetic material, the inner surfaces of the stators closely adhere to the outer surface of the spherical shell, there is no relative movement between the spherical shell and the inner surfaces of the stators, and the spherical shell is filled with magnetic fluid. The magnetic-fluid momentum sphere achieves a small size and mass, low costs, and small coupling among the axes.

Energy efficient satellite maneuvering is described herein. One disclosed example method includes maneuvering a satellite that is in an orbit around a space body so that a principle sensitive axis of the satellite is oriented to an orbit frame plane to reduce gravity gradient torques acting upon the satellite. The orbit frame plane is based on an orbit frame vector.

An attitude control apparatus for a satellite includes: at least three electric motors, wherein the at least three electric motors are arranged in such a way that a torque may be generated with any orientation of an associated torque vector, and a controller, wherein the controller is configured to drive the at least three electric motors based on a torque controller. The torque controller is adapted to operate the at least three electric motors outside a rest state only when an acceleration torque and a braking torque are required to execute an agile attitude change maneuver. There is also described an associated method.

The invention relates to small satellites capable to fly in formation (10), in particular nano- or picosatellites with a mass of 10 kg or less, for LEO applications, comprising a housing (12) and at least one plug-in board (14) arranged in the housing (12) with a predetermined functionality and a propulsion system (16) for generating a directed pulse in the direction of the flight trajectory T.sub.k.

It is proposed that the small satellite (10) comprises an independent and autonomously working collision avoidance system (18), which is capable of adapting a trajectory correction T.sub.kk of the trajectory T.sub.k by the propulsion system (16), when a collision with an object (30) is expected.

In a further independent aspect, the invention relates to a formation (100) composed of several small satellites capable to fly in formation (10), wherein a relative position and flight trajectory T.sub.k of each small satellite (10) is modifiable via the independently and autonomously working collision avoidance system (18).

An orbit transition apparatus that transitions an orbit of a payload in outer space includes a rotating body, an adapter disposed on a center part of the rotating body for docking a payload, a launch module disposed outside of the rotating body for launching the payload, and a thruster for rotating the rotating body. The launch module may launch the payload to a target orbit.

Embodiments of Reaction Wheel Assembly (RWA) systems are provided, which include multi-faceted bracket structures to which RWAs are mounted. In one embodiment, the RWA system includes a bracket structure, which is assembled from multiple (e.g., two to four) interchangeable panels. Each bracket panel may define or include a mount bracket to which an RWA is mounted. In certain embodiments, the bracket panels may include integral bearing cartridge features, which contain the spin bearings of the RWAs. The interchangeable panels may have interconnect features, which align and which possibly interlock to position the panels in a precise angular relationship when the multi-faceted bracket structure is assembled. In other embodiments wherein the bracket structure is assembled from two interchangeable panels or produced as a single piece, the multi-faceted bracket structure may have a peaked form factor supportive of two RWAs, which are mounted to the bracket structure in a back-to-back relationship.

Energy efficient satellite maneuvering is described herein. One disclosed example method includes maneuvering a satellite that is in an orbit around a space body so that a principle sensitive axis of the satellite is oriented to an orbit frame plane to reduce gravity gradient torques acting upon the satellite. The orbit frame plane is based on an orbit frame vector.

Energy efficient satellite maneuvering is described herein. One disclosed example method includes maneuvering a satellite that is in an orbit around a space body so that a principle sensitive axis of the satellite is oriented to an orbit frame plane to reduce gravity gradient torques acting upon the satellite. The orbit frame plane is based on an orbit frame vector.

A method, for providing spatial stability and electrical power with a hybrid power source and control moment gyroscope (HPCMG), includes producing spatial stability force for the HPCMG by spinning a central mass within a first transverse gimbal assembly about a first axis of rotation of a control moment gyroscope (CMG). The CMG includes the first transverse gimbal assembly, the central mass, and a second gimbal assembly rotationally connected to the first transverse gimbal assembly. The first transverse gimbal assembly is rotationally connected to the central mass at a first position of the first transverse gimbal assembly and at a second position of the first transverse gimbal assembly along the first axis of rotation. The method includes producing a voltage potential with the central mass. The method includes charging or discharging the central mass through conductive bearings.