A service satellite having a body, a controller and a docking unit including a telescopic arm, mounted on a 6-DOF parallel manipulator, and two additional gripping arms. The telescopic arm, deployed from the 6-DOF manipulator, is equipped with a pair of rapid closure digits. The telescopic arm facilitates capturing the launch adaptor ring of a client spacecraft, even during tumbling. The 6-DOF parallel manipulator has force sensors and can accommodate post capturing relative motion through active compliance control and controlled de-tumbling, for avoiding generation of high forces in the telescopic arm. After relative rate annihilation, the telescopic arm retracts and the client ring is secured to the 6-DOF manipulator with the help of a pair of clamps. After the ring is secured, two additional gripping arms secure a rigid connection with the launcher ring so that the docking connection comprises three equally spaced connections.

A service satellite for providing station keeping services to a host satellite has a body, and a gripping mechanism attached to the body. The gripping mechanism is adapted to attach to an interface ring extending from an external surface of the host satellite to form an interconnection between the host satellite and the service satellite through the externally extending interface ring. Attaching the gripping mechanism to the interface ring forms an interconnected unit having a combined center of mass. The service satellite has at least two movable thrusters and at least one controller. The at least one controller maintains the interconnected unit in a substantially stationary orbit by selectively orienting the two thrusters such that the thrust vectors from the two thrusters do not pass through the combined center of mass, and are each offset from the combined center of mass.

An orbiting satellite can be maintained in a geosynchronous orbit (e.g., with an orbital period equal to one sidereal day) at an altitude other than 35,786 km by equipping the satellite with at least one radial thruster. Radial thrusters on the anti-Earth-facing side of the satellite allow for artificial geosynchronous orbits higher than the natural altitude, while radial thrusters on the Earth-facing side of the satellite allow for artificial geosynchronous orbits lower than the natural altitude. This allows a geosynchronous satellite to evade threats, such as orbital debris and/or hostile spacecraft, without losing signal to ground based antennas. Similar techniques can also be used for surveillance of satellites in geosynchronous orbits.

A control algorithm that determines one or more deviations in an orbit of a companion satellite, and control the companion satellite to minimize effects of perturbing forces.

The present invention relates to a service satellite having a body, a controller and a docking unit. The docking unit includes at least two foldable, adjustable gripping arms pivotally mounted on the satellite body, each gripping arm being pivotable relative to the satellite body, and a gripping end at each free end of the gripping arms, wherein the gripping ends are adapted and configured to capture and grip a target portion of an orbiting satellite. Each gripping arm is controllable independently by the controller, which coordinates the motion of the arms. The service satellite also includes a propulsion unit including a first thruster mounted adjacent a Nadir end of the service satellite body, and a balance thruster, the balance thruster being distanced from the first thruster and facing a different direction than the first thruster, propellant for the thruster and the balance thruster; and means for aligning the thrusters so that a thrusting vector passes through a joint center of gravity of the service satellite and the serviced satellite.

Apparatus and methods for stationkeeping in a satellite. The satellite includes a north electric thruster and a south electric installed on a zenith side, an east chemical thruster installed on an east side, and a west chemical thruster installed on a west side. An orbit controller detects a failure of one of the electric thrusters. In response to the failure, the orbit controller controls a burn of the remaining electric thruster proximate to an orbital node. The orbit controller controls a burn of one of the chemical thrusters at 90??5? from the burn of the remaining electric thruster, and controls a burn of the other one of the chemical thrusters at 270??5? from the burn of the remaining electric thruster.

A propulsion system for the orbit control of a satellite in Earth orbit driven at a rate of displacement along an axis V tangential to the orbit comprises two propulsion modules, fixed to the satellite, and facing one another relative to the plane of the orbit, each of the propulsion modules comprising, in succession: a motorized rotation link about an axis parallel to the axis V; an offset arm; and a plate supporting two thrusters, suitable for delivering a thrust on an axis, arranged on the plate on either side of a plane P at right angles to the axis V passing through a center of mass of the satellite; each of the two thrusters being oriented in such a way that the thrust axes of the two thrusters are parallel to one another and at right angles to the axis V.

A satellite, intended to be placed in a station in orbit about a celestial body, including a first electrical thruster of orientatable thrust direction, a second electrical thruster of orientatable thrust direction, and an electrical thruster of fixed orientation that is fixed with respect to the satellite and of line of thrust passing through the center of gravity of the satellite. The satellite includes two electrical-thruster power units and an electrically interconnecting network connecting a first power unit to the first thruster of orientatable thrust direction and to the thruster of fixed orientation, and connecting a second power unit to the second thruster of orientatable thrust direction and to the thruster of fixed orientation. Each of the power units is configured to power either the associated thruster of orientatable thrust direction or the thruster of fixed orientation.

A satellite, intended to be placed in a station in orbit about a celestial body, including a first electrical thruster of orientatable thrust direction, a second electrical thruster of orientatable thrust direction, and an electrical thruster of fixed orientation that is fixed with respect to the satellite and of line of thrust passing through the center of gravity of the satellite. The satellite includes two electrical-thruster power units and an electrically interconnecting network connecting a first power unit to the first thruster of orientatable thrust direction and to the thruster of fixed orientation, and connecting a second power unit to the second thruster of orientatable thrust direction and to the thruster of fixed orientation. Each of the power units is configured to power either the associated thruster of orientatable thrust direction or the thruster of fixed orientation.

An object is to more accurately assist avoidance of a collision between space objects such as satellites or space debris in outer space. A recorder processing unit acquires flight forecast information indicating a flight forecast of each of a plurality of space objects from a management business device used by a management business operator that manages the plurality of space objects. Based on the acquired flight forecast information, the recorder processing unit sets a forecast epoch of an orbit of each of the plurality of space objects, a forecast orbital element that identifies the orbit, and a forecast error that is forecast for the orbit, as orbit forecast information. The recorder processing unit stores a space information recorder including the orbit forecast information in a storage unit.