Multiple hold down and release device for restraining and releasing payload from spacecraft, and method for releasing payload from spacecraft and method for installing such multiple hold down and release device

Abstract

To provide a multiple hold down and release device for restraining and releasing a payload from a spacecraft 4.SOLUTION: A multiple hold down and release device comprises: a plurality of hold-down assemblies placed on a periphery of the device, each comprising a hold-down bracket attached to a payload 3 and a hold-down support, both of which have conical mating surfaces, respectively, each hold-down support comprising at least one torsion spring around an axis; a plurality of pairs of connecting levers 5, each of the connecting levers comprising a first end to be coupled to a corresponding hold-down support such that each corresponding lever is articulated with the corresponding hold-down support through the axis; and a second end opposite to the first end; a plurality of restraint cables 6 joining the second ends of each pair of connecting levers and arranged radially with a central area where the restraint cables cross; and a central release actuator 1 configured to be able to cut the restraint cables.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a device for holding and releasing payloads (equipment and cargo on a spacecraft) from a spacecraft. The device is used to hold and release payloads such as antennas, solar panels, booms, etc. from a spacecraft, and belongs to the field of holding-down and release mechanisms (HDRM).

[0002] The present invention relates to a method for releasing a payload from a spacecraft and to a method for installing such a multi-holding and release device (i.e. a multi-point holding and release device). [Background technology]

[0003] In order to constrain all deployable appendages that form part of the spacecraft during the initial phase of the mission, the spacecraft will be provided with a system that provides a rigid connection at launch and allows them to be safely released and deployed once orbit is reached.

[0004] In current solutions, each payload is typically attached to the spacecraft via a number of discrete points (usually between two and six points) called a retention-and-release mechanism, which pre-loads the deployable appendage onto the spacecraft.

[0005] Each payload requires a specific style of hold-down point, potentially resulting in a significant number of hold-down points, and therefore a large number of release actuators and all associated equipment per spacecraft, such as harnesses, actuation signals, etc. The release of this number of discrete mechanisms must be precisely performed to ensure synchronicity of their actuation, entailing a significant power consumption for the satellite.

[0006] Therefore, the spacecraft must be designed to manage a large number of separation signals (two per separation nut for redundancy). The initiation system can sometimes limit the number of separation signals, but otherwise manages the separation using very expensive controller systems, converters and harnesses, at a cost and weight penalty.

[0007] Another drawback of these systems is that many parts remain with the payload after separation. The separation of this number of discrete retention and release mechanisms also generates a large shock during a separation event due to the rapid release of preload (possibly initiated by pyrotechnic actuators) near the spacecraft interface.

[0008] One way to reduce the shock delivered by these retention and release systems is to slow down the release of the preload, but this increases the actuation time and dispersion of the mechanism, which means it is less favorable to simultaneous separation of the retention and release mechanism.

[0009] This simultaneous separation is highly desirable so that the separation system, typically formed by a spring, can eject the payload with minimal angular disturbance upon separation.

[0010] The high reliability required for each of the retention and release mechanisms for each spacecraft makes the separation system a high percentage of the total cost. The cost and weight implications of these new satellite platforms necessitate the need to address alternative solutions.

[0011] Patent document 1 discloses an apparatus for restraining and releasing a deployable body attached to a support structure, the apparatus comprising a pair of subassemblies operable between a stowed state and a released state, each of which is attached to either the deployable body or the support structure and includes mating surfaces that interlock with each other in the stowed state to substantially prevent lateral movement of the deployable body relative to the support structure, a releasable tension element connected to both subassemblies and applying a compressive preload to the subassemblies to hold the subassemblies together, a force measurement system allowing monitoring of said applied compressive preload, and a release device for releasing said preload allowing free separation of the subassemblies. The apparatus further comprises a preload application mechanism embedded in the apparatus to apply a substantially pure tensile preload to the releasable tension element.

[0012] Patent document 2 discloses an apparatus for separating a rocket stage from a spacecraft to be separated, the apparatus including a pyro-actuator having a piston installed therein and connected to a locking device of a connecting element, the pyro-actuator being provided with a split ring, the connecting elements being made in the form of rods arranged in series and installed inside the piston so as to be mutually movable, the rods being connected to the rods via a rotating joint, and the split ring being installed between the piston shoulder and the piston end fixed to the rod.

[0013] Patent Document 3 discloses a payload separation system including a removable retention device installed between a load-supporting structure and a payload, the system including a discretely arranged mechanical lock with retention and locking links on the load-supporting structure of the device, the mechanical lock being rotatably fixed at the center of the installation circle of the lock and connected to a rotating multi-beam star that is held in an initial position of rotation by a pyroelectric means, and a spring pusher for separation. The system for separating the load-supporting structure includes a mechanical lock with retention and locking links, the mechanical lock being rotatably fixed at the center of the installation circle of the lock and connected to a rotating multi-beam star that is rotatably fixed at the center of the installation circle of the lock and held in an initial position of rotation by a pyroelectric means.

[0014] Patent Document 4 discloses an "Apparatus for Holding a Moving Structure on a Spacecraft" including a stationary structure fixed to the spacecraft, an actuator, a releasable member driven to move axially relative to the stationary structure upon actuation of the actuator, and a locking assembly configured to hold or release the moving structure depending on the axial position of the releasable member. The locking assembly comprises a plurality of circumferentially arranged locking members radially movable to engage and disengage the moving structure with a "V" shaped groove disposed on an annular plate attached to the appendage, the locking members being connected to the releasable member via a first lever such that the axial movement of the releasable member and the radial movement of the locking member are coupled to each other by a bent lever type mechanism.

[0015] US Pat. No. 5,399,633 discloses an example of a hold-down and release mechanism (HDRM) for releasing a small spacecraft from a launcher, the hold-down and release mechanism having a central actuator.

[0016] US Patent No. 6,399,633 shows a central release system in which several discrete points are held by cranks. These cranks are preloaded with tension cables and connected between them by pulleys to achieve synchronicity in the release of all the holding and release mechanisms (HRMs). When the release actuator releases the tension in the system, these cranks have to pull on the cables and pulleys, which can destroy the synchronicity.

[0017] US Patent No. 5,393,633 discloses a retention and release system for discrete restraint points in which a preload is applied by a tension cable which is severed by a heating element.

[0018] Non-Patent Document 1 discloses other separation systems, including several systems for multiple satellite launches. One of these systems consists of four retention mechanisms and a plate structure, but with only one release point.

[0019] For typical payloads (antennas, solar arrays, booms, etc.) that are attached via discrete points, they are primarily grasped and released via a retention and release mechanism (HDRM), requiring one release actuator for each point. Since the total number of release actuators is an indicator of the cost and reliability of a separate system, the space industry is increasingly interested in utilizing central actuation systems.

[0020] Therefore, there is a need to provide a multi-retention and release system for restraining and releasing a payload from a spacecraft that reduces overall mass, cost, induced loads on the structure, and ejection shock during release without compromising system reliability. [Prior art documents] [Patent documents]

[0021] [Patent Document 1] European Patent Application Publication No. 2298648 [Patent Document 2] Russian Patent No. 2111905 [Patent Document 3] Russian Patent No. 2396191 [Patent Document 4] European Patent Application Publication No. 2213572 [Patent Document 5] International Publication No. 2020 / 249831 Brochure [Patent Document 6] DE 3215432 A1 [Patent Document 7] European Patent Application Publication No. 0121959 [Non-patent literature]

[0022] [Non-Patent Document 1] Andreas Jonsson and Magnus Engstrom, "Enabling Solutions for Small Satellite Space Access," 13th Reinventing Space Conference, November 2015. Summary of the Invention [Problem to be solved by the invention]

[0023] SUMMARY OF THE PRESENT EMBODIMENT It is an object of the present invention to provide a multi-retention and release system for restraining and releasing a payload from a spacecraft for commanded separation which overcomes the above-mentioned drawbacks. [Means for solving the problem]

[0024] The present invention provides a multi-retention and release apparatus for restraining and releasing a payload from a spacecraft, comprising: a plurality of support assemblies disposed around a periphery of the apparatus, each of which includes a support bracket configured to be attached to a payload and a support connected to the spacecraft, both the support bracket and the support having conical mating surfaces, each support including at least one torsion spring about an axis; a plurality of pairs of connecting levers, each of the connecting levers including a first end configured to be coupled to a corresponding support such that each corresponding lever is articulated to the corresponding support via a shaft, and a second end opposite the first end; a plurality of tether cables engaging the second ends of each pair of connecting levers and arranged radially with a central region where the tether cables intersect; a central release actuator configured to sever the restraining cables; The present invention provides a retention and release device comprising:

[0025] The present invention also provides a multi-retention and release apparatus for restraining and releasing a payload from a spacecraft, comprising: a plurality of support assemblies disposed around a periphery of the apparatus, each of which includes a support bracket configured to be attached to a payload and a support connected to the spacecraft, both the support bracket and the support having conical mating surfaces, each support including at least one torsion spring about an axis; a plurality of connecting levers, each of the connecting levers including a first end configured to be coupled to a corresponding support such that each corresponding lever is articulated to the corresponding support via a shaft, and a second end opposite the first end; a restraining cable engaged with the second end of the connecting lever; a release actuator configured to sever the restraining cable; The present invention provides a retention and release device comprising:

[0026] The invention also comprises a method for releasing a payload from a spacecraft according to claims 11 and 13, and a method for providing a multi-holding and releasing device for restraining and releasing a payload from a spacecraft according to claims 12 and 14.

[0027] Other advantages of the present invention include: Reduced overall cost as only one central release actuator is required; Reduction in total mass due to fewer release actuators, harnesses, batteries, etc.; and Gradual release of energy, especially important for shock-sensitive payloads such as solar arrays or optical instruments.

[0028] The present invention is also a versatile device that allows the number of levers and restraining cables, as well as their lengths, to be adapted to suit various needs.

[0029] Other features and advantages of the present invention will become apparent from the following detailed description of several embodiments which illustrate its objectives in connection with the accompanying drawings. [Brief description of the drawings]

[0030] [Figure 1] FIG. 2 is a diagram of the multi-holding and release apparatus of the present invention in stowed mode with a payload attached to a spacecraft. [Diagram 2] FIG. 2 is a view of the multi-holding and releasing device of FIG. 1 in a deployed mode. [Diagram 3] FIG. 2 is a detailed view of some elements of the multi-hold-and-release device of the present invention in a stowed mode. [Figure 4] FIG. 2 is a detailed view of some elements of the multi-holding release device of the present invention in a deployed mode. [Figure 5-6] 14A-14D show bottom views of different configurations for the multi-hold release device of the present invention. [Figure 7-8] 14A-14D show bottom views of different configurations for the multi-hold release device of the present invention. [Figure 9-10] 13A-13C are views of the restraining cables before and after being severed by a central release actuator. [Figure 11] 1 shows multiple radially arranged tether cables with a central region where the tether cables cross and a central release actuator. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0031] FIG. 1 shows the multi-holding and release apparatus of the present invention in a closed or stowed mode attaching a payload 3 to a spacecraft 4, and FIG. 2 shows the multi-holding and release apparatus of FIG. 1 in an open or deployed mode with the payload 3 released.

[0032] A multi-retention and release device for restraining and releasing a payload 3 from a spacecraft 4, a plurality of support assemblies 19 (see Figures 3 and 4) arranged around the periphery of the device, each of which includes a support bracket 11 configured to be attached to a payload 3 and a support 20 joined to the spacecraft 4, both of which have conical mating surfaces 10, 10', each support 20 including at least one torsion spring 9 about an axis 17; a plurality of pairs of connecting levers 5, each of the connecting levers 5 including a first end 14 configured to be coupled to a corresponding holding support 20 such that each corresponding lever 5 is articulated to the corresponding holding support 20 via a shaft 17, and a second end 15 opposite the first end 14; a plurality of restraining cables 6 (see Figures 5, 7 and 8) engaging the second ends 15 of each pair of connecting levers 5 and arranged radially with a central region where the restraining cables 6 intersect; a central release actuator 1 configured to be able to cut the restraining cables 6; Includes.

[0033] Another form of a multi-holding and releasing apparatus for restraining and releasing a payload 3 from a spacecraft 4 is shown in FIG. a plurality of support assemblies 19 (see Figures 3 and 4) arranged around the periphery of the device, each of which includes a support bracket 11 configured to be attached to a payload 3 and a support 20 joined to the spacecraft 4, both of which have conical mating surfaces 10, 10', each support 20 including at least one torsion spring 9 about an axis 17; a plurality of connecting levers 5, each of the connecting levers 5 including a first end 14 configured to be coupled to a corresponding holding support 20 such that each corresponding lever 5 is articulated to the corresponding holding support 20 via an axis 17, and a second end 15 opposite the first end 14; one restraining cable 6 (see FIG. 6 ) engaged with the second end 15 of the connecting lever 5; a release actuator 1 configured to be able to cut the restraining cable 6; Includes.

[0034] In the configuration of FIG. 6, a single restraining cable 6 can connect the second ends 15 of all levers 5 simultaneously.

[0035] The apparatus of the present invention provides retention and structural continuity between the payload 3 and the spacecraft 4 at any desired number and location of discrete points (retention assemblies 19 ) and simultaneous release by actuation of a unique release actuator 1 .

[0036] Each retention assembly 19 consists of a fixed subassembly (retention support 20) that remains on the spacecraft 4 and a retention bracket 11 attached to the payload 3. Both retention support 20 and retention bracket 11 stay together on release by cup-cone contact with conical mating surfaces 10, 10' preloaded by the connecting lever 5.

[0037] According to Fig. 3, these levers 5 apply a force F to the deployable bracket 11 that is (D / d) times greater than the load f applied by the tensioned restraining cable 6, the distances D and d being visible in Fig. 3. This force F makes it possible to hold the cone of the deployable bracket 11 in the cone of the holding support 20. The load f is applied to the cable 6 via a tension element 13 and can be monitored via a preload measuring sensor 2 arranged on the lever 5.

[0038] When the release actuator 1 severs the tensioned restraining cable 6 , the involved levers 5 release the preload on the deployable brackets 11 and retract about their axes 17 by means of at least one torsion spring 9 .

[0039] A multi-holding and releasing device for holding and releasing a payload 3 from a spacecraft 4 may include a damper 8 on each holding support 20 to limit the movement of the lever 5 about the corresponding axis 17 .

[0040] The multi-holding and releasing device for restraining and releasing a payload 3 from a spacecraft 4 may further comprise, on each holding support 20, a latch 7 suitable for retaining the corresponding lever 5.

[0041] Once retracted, the movement of the lever 5 is damped to reduce shock emissions and the lever 5 is captured in its final position within the latch 7 so as not to impair the deployment of the retaining bracket 11.

[0042] The multi-holding and releasing device for restraining and releasing a payload 3 from a spacecraft 4 may further include a strain gauge 2 on the connecting lever 5 .

[0043] In another embodiment, the central release actuator 1 is a thermal knife or cutter.

[0044] In another embodiment, the restraining cables 6 are made of a fusible material that can be cut with a thermal knife (eg, kevlar) or a cuttable material for a conventional cutter actuator (eg, steel).

[0045] The multi-retention and release device for restraining and releasing the payload 3 from the spacecraft 4 may further include a tensioner 13 adjacent the second end 15 of each connecting lever 5 to apply a preload to the second end 15 of each connecting lever 5.

[0046] In one embodiment, the retention assemblies 19 are arranged in a circular configuration in plan view (FIG. 5).

[0047] In one embodiment, the retention assemblies 19 are arranged in a polygonal configuration in plan view (FIGS. 7 and 8).

[0048] A method for releasing a payload 3 from a spacecraft 4 using the multi-retention and release device of FIG. 5, 7 or 8 in a retention position where the payload 3 is attached to the spacecraft 4 at several discrete points by corresponding retention brackets 11 and a retention support 20 is attached to the spacecraft 4, the method comprising: activating the actuator 1 to sever the restraining cable 6; the connecting lever 5 of each pair of connecting levers 5 being released from the corresponding restraining cable 6 and rotated by its elastic energy and by at least one torsion spring 9; releasing the first end 14 of each connecting lever 5 from the corresponding retaining bracket 11 to unlock the corresponding retaining bracket 11 and allow separation of the payload 3 from the spacecraft 4; Includes.

[0049] A method of providing a multi-holding and releasing device for restraining and releasing a payload from a spacecraft using a plurality of the hold-down and releasing devices of FIG. 5, FIG. 7 or FIG. 8, the method comprising: Attaching a support 20 to a spacecraft 4; Attaching a retaining bracket 11 to a payload 3; joining the second ends 15 of each pair of connecting levers 5 to the restraining cables 6 and preloading them; attaching a central release actuator 1 to the spacecraft 4 such that the central release actuator 1 is located in a central region where the restraining cables 6 cross; Includes.

[0050] A method of releasing a payload 3 from a spacecraft 4 using the multi-retention release device of FIG. 6 such that in a retention position, the payload 3 is attached to the spacecraft 4 at several discrete points by corresponding retention brackets 11 and retention supports 20 are attached to the spacecraft 4, the method comprising: activating the actuator 1 to sever the restraining cable 6; the connecting lever 5 being released from the restraining cable 6 and rotated by its elastic energy and by the at least one torsion spring 9; releasing the first end 14 of each connecting lever 5 from the corresponding retaining bracket 11 to unlock the corresponding retaining bracket 11 and allow separation of the payload 3 from the spacecraft 4; Includes.

[0051] A method of providing a multi-retention and release device for restraining and releasing a payload from a spacecraft using the multiple retention and release devices of FIG. 6, the method comprising: Attaching a support 20 to a spacecraft 4; Attaching a retaining bracket 11 to a payload 3; joining the second end 15 of the connecting lever 5 to the restraining cable 6 and preloading it; attaching a release actuator 1 to a spacecraft 4 such that the release actuator 1 is disposed on a restraining cable 6; Includes.

[0052] 9 and 11 show a release actuator 1 configured to cut several restraining cables 6 simultaneously, while FIG. 10 shows a release actuator 1 configured to cut the restraining cables 6 piece by piece.

[0053] While the present invention has been fully described in relation to preferred embodiments, it will be apparent that the invention is not limited to these embodiments, but is to be regarded as limited by the content of the appended claims, within the scope of which modifications may be introduced. [Explanation of symbols]

[0054] 1 Central Release Actuator 3. Payload 4. Spaceship 5 Connection lever 6 Restraining Cable 11 Retaining bracket 14 First end of connecting lever 15 Second end of connecting lever 17 Axis 19 Retaining assembly (multiple) 20 Holding support

Claims

1. A multi-retention and release device for restraining and releasing a payload (3) from a spacecraft (4), comprising: a plurality of support assemblies (19) arranged around the periphery of the device, each of which comprises a support bracket (11) configured to be attached to the payload (3) and a support support (20) joined to the spacecraft (4), both the support bracket (11) and the support support (20) having conical mating surfaces (10, 10'), each support support (20) comprising at least one torsion spring (9) around an axis (17); a plurality of pairs of connecting levers (5), each of the connecting levers (5) having a first end (14) configured to be coupled to a corresponding holding support (20) such that each corresponding connecting lever (5) is articulated to the corresponding holding support (20) via the shaft (17), and a second end (15) opposite the first end (14); In a multi-holding and releasing device comprising: a plurality of restraining cables (6) engaging the second ends (15) of each pair of said connecting levers (5) and arranged radially with a central region where the restraining cables (6) intersect; a central release actuator (1) configured to be capable of cutting the restraining cable (6); A multi-holding and releasing device, further comprising:

2. A multi-retention and release device for restraining and releasing a payload (3) from a spacecraft (4), comprising: a plurality of support assemblies (19) arranged around the periphery of the device, each of which comprises a support bracket (11) configured to be attached to the payload (3) and a support support (20) joined to the spacecraft (4), both the support bracket (11) and the support support (20) having conical mating surfaces (10, 10'), each support support (20) comprising at least one torsion spring (9) around an axis (17); a plurality of connecting levers (5), each of the connecting levers (5) having a first end (14) configured to be coupled to a corresponding holding support (20) such that each corresponding connecting lever (5) is articulated to the corresponding holding support (20) via the shaft (17), and a second end (15) opposite the first end (14); In a multi-holding and releasing device comprising: a restraining cable (6) engaged with the second end (15) of the connecting lever (5); a release actuator (1) configured to be capable of cutting the restraining cable (6); A multi-holding and releasing device, further comprising:

3. 3. A multi-holding and releasing device for restraining and releasing a payload (3) from a spacecraft (4) as claimed in claim 1 or 2, further comprising a damper (8) on each holding support (20) for limiting the movement of the connecting lever (5) around the corresponding axis (17).

4. A multi-holding and releasing device for restraining and releasing a payload (3) from a spacecraft (4) as claimed in claim 1, 2 or 3, further comprising a latch (7) on each holding support (20) suitable for retaining the corresponding connecting lever (5) after release.

5. A multi-retention and release device for restraining and releasing a payload (3) from a spacecraft (4) according to any one of claims 1 to 4, further comprising a strain gauge (2) on said connecting lever (5).

6. A multi-holding and releasing device for restraining and releasing a payload (3) from a spacecraft (4) according to any one of claims 1 to 5, wherein the central release actuator (1) is a thermal knife or cutter.

7. A multi-retention and release device for restraining and releasing a payload (3) from a spacecraft (4) according to any one of claims 1 to 6, wherein the restraining cables (6) are made of kevlar.

8. 8. A multi-retention and release device for restraining and releasing a payload (3) from a spacecraft (4) as claimed in any one of claims 1 to 7, further comprising a tensioner (13) adjacent the second end (15) of each connecting lever (5) for preloading the second end (15) of each connecting lever (5).

9. 2. The multi-retention and release device for restraining and releasing a payload (3) from a spacecraft (4) as claimed in claim 1, wherein the retention assembly (19) is configured in a circular shape in a plan view.

10. 2. The multi-retention and release device for restraining and releasing a payload (3) from a spacecraft (4) as claimed in claim 1, wherein the retention assembly (19) is configured in a polygonal shape in a plan view.

11. A method for releasing a payload (3) from a spacecraft (4), comprising the steps of: In a holding position, the payload (3) is attached to the spacecraft (4) at a plurality of discrete points by corresponding holding brackets (11) and the holding supports (20) are attached to the spacecraft (4) using the multi-holding and releasing device according to claim 1 and the following steps are carried out: activating the release actuator (1) to sever the restraining cable (6); the connecting lever (5) of each pair of said connecting levers (5) being released from the corresponding restraining cable (6) and pivoting due to its elastic energy and said at least one torsion spring (9); a first end (14) of each connecting lever (5) being released from a corresponding retaining bracket (11) to unlock the corresponding retaining bracket (11) and allow separation of the payload (3) from the spacecraft (4); The method of claim 1, further comprising:

12. 13. A method of installing a multi-holding and releasing device for restraining and releasing a payload from a spacecraft, comprising using a multi-holding and releasing device according to claim 1 and comprising the steps of: attaching said support (20) to said spacecraft (4); attaching the retaining bracket (11) to the payload (3); joining and preloading the second ends (15) of each pair of said connecting levers (5) with restraining cables (6); attaching a central release actuator (1) to the spacecraft (4) such that the central release actuator (1) is located in a central region where the tether cables (6) cross; The method of claim 1, further comprising:

13. A method for releasing a payload (3) from a spacecraft (4), comprising the steps of: In the holding position, the payload (3) is attached to the spacecraft (4) at a plurality of discrete points by the corresponding holding brackets (11) and the holding supports (20) are attached to the spacecraft (4) using the multi-holding and releasing device according to claim 2 and the following steps are carried out: activating the release actuator (1) to sever the restraining cable (6); the connecting lever (5) being released from the restraining cable (6) and pivoting due to its elastic energy and the at least one torsion spring (9); a first end (14) of each connecting lever (5) being released from a corresponding retaining bracket (11) to unlock the corresponding retaining bracket (11) and allow separation of the payload (3) from the spacecraft (4); The method of claim 1, further comprising:

14. A method of installing a multi-holding and releasing device for restraining and releasing a payload from a spacecraft, comprising using a multi-holding and releasing device according to claim 2 and comprising the steps of: attaching said support (20) to said spacecraft (4); attaching the retaining bracket (11) to the payload (3); joining the second end (15) of the connecting lever (5) with a restraining cable (6) and preloading it; attaching the release actuator (1) to the spacecraft (4) such that the release actuator (1) is disposed on the tether cable (6); The method of claim 1, further comprising:

Images