System for the Release of Satellites from a Launch Vehicle

Abstract

A release system for the release of satellites from a launch vehicle is provided that includes: (i) a torsion bar, having a first end which is fixed by means of support means to a launch vehicle and is locked in rotation around a longitudinal axis of the torsion bar, and a second end which is connected by means of hinge means to the launch vehicle and is free to rotate around the longitudinal axis; (ii) at least one launch arm extending perpendicularly from the torsion bar and comprising (a) a torsion lever having a first end which is fixed to the torsion bar in an integral manner, and (b) a guide having a first end connected to a second end of the torsion lever, and a second free end; (iii) at least one slider which is fixed in an integral manner to a satellite to be launched and arranged to engage the guide in a sliding manner; and (iv) and a limit stop element designed to act upon the torsion lever to stop the rotation of the launch arm around the longitudinal axis.

Claims

1. A release system (1) for release of satellites from a launch vehicle; said release system (1) comprising: (i) a torsion bar (2) having a first end (2a), which is fixed to a launch vehicle (3) by means of support means (4) and is locked in the rotation around a longitudinal axis (X) of the torsion bar (2), and a second end (2b), which is connected to said launch vehicle (3) by means of hinge means (5) and is free to rotate around said longitudinal axis (X); (ii) at least one launch arm (6) extending perpendicularly from said torsion bar (2) and comprising (a) a torsion lever (7) having a first end (7a) which is fixed to said torsion bar (2) in an integral manner, and (b) a guide (8) having a first end (8a) connected to a second end (7b) of said torsion lever (7), and a second free end (8b); (iii) at least one slider (10), which is fixed to a satellite (18) to be launched in an integral manner and is arranged so as to engage, in a sliding manner, said guide (8); and (iv) a limit stop element (12), which is designed to act on said torsion lever (7) to interrupt the rotation of the launch arm (6) around the longitudinal axis (X).

2. A release system for release of satellites from a launch vehicle according to claim 1, wherein said first end (8a) of said guide (8) is connected by means of a locking joint (9) to said second end (7b) of said torsion lever (7), to enable changing the angle between said guide (8) and said torsion lever (7).

3. A release system for release of satellites from a launch vehicle according to claim 2, wherein said guide (8) comprises an energy absorber (11).

4. A release system for release of satellites from a launch vehicle according to claim 1, wherein the release system further comprises torsion pre-loading means (17), which act upon said first end (2a) of the torsion bar (2).

5. A release system for release of satellites from a launch vehicle according to claim 1, wherein said limit stop element 12 comprises a striking surface (13), against which a portion of said respective launch arm (7) strikes in order to end its stroke.

6. A release system for release of satellites from a launch vehicle according to claim 1, wherein the release system further comprises a reversible locking element, which is designed to lock the launch arm on the limit stop element.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Hereinafter an embodiment is reported for illustrative and non-limiting purposes with the aid of the accompanying figures, wherein:

[0020] FIG. 1 is an overall perspective view of the release system of the present invention according to an embodiment;

[0021] FIG. 2 shows the movement steps of a satellite which is subjected to the action of the release system according to the present invention;

[0022] FIG. 3 shows a launch vehicle carrying two satellites to each of which a release system according to the present invention is applied.

BEST MODE FOR CARRYING OUT THE INVENTION

[0023] In FIG. 1, 1 denotes as a whole the system according to a preferred embodiment of the present invention.

[0024] The system 1 comprises a torsion bar 2 fixed to a launch vehicle 3. In particular, the torsion bar 2 has a first end 2a which is fixed to the launch vehicle 3 by a support 4 and a second end 2b fixed to the launch vehicle 3 by a hinge 5. The first end 2a is locked in rotation, i.e. it cannot rotate around the longitudinal axis X of the torsion bar during the loading carried out by the rotation of a launch arm as described hereinafter. Conversely, the second end 2b is free to rotate around the X axis thanks to the hinge 5. As will be shown hereinafter, the torsion resulting from the fact that the first end 2a is locked while the second end 2b is free to rotate, obtains the elastic loading required to release the satellite.

[0025] The system 1 comprises a launch arm 6, which is the member transmitting the thrust generated by the torsion of the bar to the satellite to be launched. The launch arm 6 consists of a torsion lever 7 and a guide 8 connected to the torsion lever 7 by a locking joint 9. In particular, the torsion lever 7 has a first end 7a which is connected in an integral manner to the torsion bar 2 and a second end 7b engaged by the locking joint 9, while the guide 8 has a first end 8a engaged by the locking joint 9 and a second free end 8b.

[0026] The system 1 comprises a slider 10 which is fixed, while being used, to the satellite to be launched and arranged to slide on the guide 8, and then to leave it at its second end 8b.

[0027] The presence of the locking joint 9 enables to modify the angle between the torsion lever 7 and the guide 8 and, therefore, allows to select the release direction to be transmitted to the satellite.

[0028] The guide 8 comprises an energy absorber 11 positioned near the first end 8a thereof.

[0029] The system 1 comprises a limit stop element 12, arranged to lock the rotation of the torsion lever 7 around the axis X. In particular, the limit stop element 12 comprises a striking surface 13 against which a portion of the torsion lever 7 strikes.

[0030] The system 1 comprises a locking element 14 that ensures reversible locking of the torsion lever 7 on the limit stop element 12 once the portion of the torsion lever 7 has stricken against the striking surface 13. The locking element 14, according to a preferred embodiment, comprises a slot 15 obtained in the portion of the torsion lever 7 and a pin 16 extending from the striking surface 13. A reversible male-female locking is thereby achieved. The torsion lever 7, once it has ended its stroke due to the presence of the limit stop element 12, will be locked on the striking surface 13. Obviously, unlike what has been disclosed, it is also possible to obtain the locking element 14 by making the slot in the striking surface 13 and arranging the pin on the portion of the torsion lever 7.

[0031] Finally, the system 1 comprises a torsion pre-loading element, schematically shown and indicated by 17.

[0032] The torsion pre-loading element 17 acts on the first end 2a of the torsion bar 2 and sets a base torsion level of the bar. In practice, the torsion pre-loading element 17 makes a rotation of the first end 2a of the torsion bar 2 and, subsequently, locks its position. Thereby, it will be possible to vary the elastic force of the torsion bar according to the mass of the satellite to be launched.

[0033] Preferably the torsion bar 2 is made of steel, as well as other components that are subjected to high mechanical stress, while the majority of the system is made of aluminum. Preferably, the slider 10 is made of a polymeric material so as to ensure a low level of friction between the slider 10 and the guide 8.

[0034] In use, after the locking joint 9 has been set, the launch arm 6 is rotated thus realizing a torsion (loading) of the torsion bar 2 until its position is locked by means of temporary locking means, which are removed before the satellite is launched, and not shown or described for simplicity. The satellite is thereby mounted by engaging the slider 10 attached thereto to the guide 8 of the launch arm 6.

[0035] Once the launch vehicle with the satellites has reached the separation conditions, it is possible to command the release of the satellite locking system to the launch vehicle (e.g. with a pyrotechnic belt tensioner system or with explosive bolts), and the consequent free rotation of the launch arm 6.

[0036] As illustrated in FIG. 2, once the locking of the satellite from the launch vehicle has ceased, the torsion bar 2 forces the rotation of the launch arm 6 and the satellite 18 around the X axis until the torsion lever 7 impacts against the limit stop element 12. In the thrust step, the constraint between the guide and the slider is obtained in such a way that no other trajectory is allowed to the satellite except for the desired circular one. The movement of the satellite 18 is thereby transformed from rotational to purely translational, with the slider 10 sliding along the guide 8 and then leaving it at its second end 8b. For this purpose, the guide and the slider (prismatic constraints) are sized in such a way as to give the satellite torque pulses, on the three coordinated axes, in order to cancel all possible rotations and to obtain only the desired mere translation at the exit of the guide.

[0037] It should be noted that the release system of the present invention does not release the satellite in a direction vertical to the separation plane.

[0038] This makes it possible to mount a plurality of satellites on the launch vehicle, even very close to each other.

[0039] As it can be construed from FIG. 3, the launch vehicle can accommodate two satellites and place them close to each other without the risk of them colliding during the release.

[0040] Indeed, the release system of the present invention is such that the two satellites are launched from opposite sides of the launch vehicle.

[0041] From the foregoing, it derives that the release system of the present invention, comprising a single thrust point on the satellite combined with the stabilizing effects of the prismatic guide, does not produce the rotational movement which is typical of the release systems of the known art.

[0042] The absence of rotational movement and the high release rate produced by the torsion bar make it possible to obtain the stabilization on the three satellite axes and the subsequently deployment of the solar panels sooner than with the systems of the prior art. This effect necessarily leads to the important advantage related to a lower consumption of energy from the satellite batteries with a resulting reserve energy to support possible initial emergency situations.

[0043] Moreover, the presence of the torsion pre-loading element 17 makes it possible to modify the thrust force deriving from the torsion bar according to the mass of the satellite to be launched and the desired release rate, with no need to change the components of the system.

[0044] Unlike what above disclosed, the release system of the present invention may comprise two launch arms rather than one. This variant is necessary in case the mass of the satellite is significantly high. The two launch arms, however, are connected to the same torsion bar in such a way as to prevent even the slightest asynchronous release. This solution could be implemented by means of a connecting element between a first launch arm whose end is connected to the torsion bar and a second launch arm. Such a connecting element may consist of a connecting tube arranged outside the torsion bar.