A projectile intended for damping a spacecraft (100) comprising a main body (110) and active attitude control means (150) comprises a harpoon and is intended to equip a space delivery vehicle to be projected towards the spacecraft. It comprises a passive damper (200) mounted such that it is fixed on the harpoon and suitable for generating, in cooperation with the Earth's magnetic field, a damping torque. That passive damper (200) comprises an outer enclosure (210) and an inner body (220) configured such that: the inner body, permanently magnetized, is positioned inside the outer enclosure and is capable of moving in rotation about at least one axis of rotation, the outer enclosure and the inner body comprise respectively an inner surface and an outer surface, separated by means of a viscous fluid, the outer enclosure is fixed to the main body of the spacecraft for rotation therewith once the harpoon is secured to the main body.

Technique for altering a client spacecraft's rotational rate including the precise positioning of a servicing spacecraft in close proximity of a client spacecraft, alignment of a fluid release output device on the servicing spacecraft that imparts a force on the client spacecraft by means of fluid release, and subsequent use of the fluid release output device to mitigate tumbling of the client spacecraft. This allows the servicing spacecraft to slow the rotation of a tumbling client spacecraft in order to perform additional servicing operations.

A method for determining, by reanalysis, a vibratory environment of a coupled vehicle/passenger system. A vehicle is subjected to external forces Fext and is coupled to a new passenger including multiple payloads (e.g., x=I, . . . N payload(s)). At the level of vehicle/passenger interfaces Ix, the method comprising a step DET1) for determining, based on reference interfacial acceleration .sub.x_ref of a reference passenger, the interfacial acceleration .sub.x relative to the new passenger.

A method for determining, by reanalysis, a vibratory environment of a coupled vehicle/passenger system. A vehicle is subjected to external forces Fext and is coupled to a new passenger including multiple payloads (e.g., x=I, . . . N payload(s)). At the level of vehicle/passenger interfaces Ix, the method comprising a step DET1) for determining, based on reference interfacial acceleration .sub.x_ref of a reference passenger, the interfacial acceleration .sub.x relative to the new passenger.

Techniques for performing an orbital maneuver on a spacecraft by firing a thruster include executing a first double pulse, double coast firing (DPDC) sequence with the thruster prior to the orbital maneuver, firing the thruster for a duration of the orbital maneuver, and executing a second DPDC firing sequence with the thruster subsequent to the orbital maneuver.

Techniques for performing an orbital maneuver on a spacecraft by firing a thruster include executing a first double pulse, double coast firing (DPDC) sequence with the thruster prior to the orbital maneuver, firing the thruster for a duration of the orbital maneuver, and executing a second DPDC firing sequence with the thruster subsequent to the orbital maneuver.

Feedback control circuitry includes rate limiter circuitry configured to generate a rate limited position command based on a position command for a controlled component and based on a speed command for the controlled component. The feedback control circuitry also includes error adjustment circuitry configured to apply a control gain to an error signal to generate an adjusted error signal. The error signal is based on position feedback and the rate limited position command, and the position feedback indicates a position of the controlled component. The feedback control circuitry further includes an output terminal configured to output a current command generated based on the adjusted error signal.

A projectile intended for damping a spacecraft (100) comprising a main body (110) and active attitude control means (150) comprises a harpoon and is intended to equip a space delivery vehicle to be projected towards the spacecraft. It comprises a passive damper (200) mounted such that it is fixed on the harpoon and suitable for generating, in cooperation with the Earth's magnetic field, a damping torque. That passive damper (200) comprises an outer enclosure (210) and an inner body (220) configured such that: the inner body, permanently magnetized, is positioned inside the outer enclosure and is capable of moving in rotation about at least one axis of rotation, the outer enclosure and the inner body comprise respectively an inner surface and an outer surface, separated by means of a viscous fluid, the outer enclosure is fixed to the main body of the spacecraft for rotation therewith once the harpoon is secured to the main body.

A projectile intended for damping a spacecraft (100) comprising a main body (110) and active attitude control means (150) comprises a harpoon and is intended to equip a space delivery vehicle to be projected towards the spacecraft. It comprises a passive damper (200) mounted such that it is fixed on the harpoon and suitable for generating, in cooperation with the Earth's magnetic field, a damping torque. That passive damper (200) comprises an outer enclosure (210) and an inner body (220) configured such that: the inner body, permanently magnetized, is positioned inside the outer enclosure and is capable of moving in rotation about at least one axis of rotation, the outer enclosure and the inner body comprise respectively an inner surface and an outer surface, separated by means of a viscous fluid, the outer enclosure is fixed to the main body of the spacecraft for rotation therewith once the harpoon is secured to the main body.

A system for vibration control of a cryocooler that cools an imager. The system includes a vibration sensor that is physically affixed to the cryocooler. The vibration sensor senses a physical vibration of the cryocooler and to generates a vibration signal therefrom. The system also includes cryocooler drive electronics operatively coupled to the vibration sensor and the cryocooler. The cryocooler drive electronics output a drive waveform that drives the cryocooler so as to reduce the vibration impact of the cryocooler. The harmonic content of the cryocooler drive waveform is controlled by the cryocooler drive electronics based on the vibration signal.