WO2004113170A1

WO2004113170A1 - Satellite launch apparatus

Info

Publication number: WO2004113170A1
Application number: PCT/GB2004/002567
Authority: WO
Inventors: Mohammad Anayet Rubby Ahad
Original assignee: Mohammad Anayet Rubby Ahad
Priority date: 2003-06-19
Filing date: 2004-06-16
Publication date: 2004-12-29

Abstract

A satellite container (10) for packaging a satellite during transportation thereof to a launch vehicle, comprising a body (12) defining a chamber (20) for housing a satellite (25), wherein the body (12) is configured to be coupled to or mounted on a launch vehicle for carrying the body (12) into space with the satellite housed therein. A satellite transportation module (50) for use in a multi-stage launch vehicle is also provided, the transportation module (50) being configured to be coupled to or to house the satellite container (10).

Description

SATELLITE LAUNCH APPARATUS

DESCRIPTION

TECHNICAL FIELD

The present invention relates generally to apparatus for use in launching satellites, and more particularly, but not exclusively, to apparatus for use in launching micro- satellites, e.g. small, lightweight satellites into orbit (e.g. into an 800km polar orbit) . BACKGROUND ART

Micro-satellites, e.g. comprising research or communications equipment and weighing perhaps 50kg, are known in the art as relatively low-cost devices (perhaps no more than a few million pounds Sterling) in comparison to more sophisticated satellites (perhaps worth hundreds of millions of pounds Sterling) . However, the costs involved in launching micro-satellites - even in unmanned missions - are still considerable.

Conventional satellite launching technology generally involves the use of bespoke equipment, which may have to be modified from mission to mission. Accordingly, development costs tend to be high, not least because both the payload and launch vehicle may have to be repeatedly modified during preparation for a mission. Consequently, there is a desire to minimise the costs involved in placing micro- satellites into orbit. Launch vehicles comprising a compartment for receiving a payload are well known in the art (see for example WO 01/44050, US 2002/0000495, US 5050821 and DE 3641444) . An example of a container used to transport a payload to a launch site is disclosed in US 6237795. DISCLOSURE OF THE INVENTION

According to the present invention, there is provided a satellite container for packaging a satellite during transportation thereof to a launch vehicle, comprising a body defining a chamber for housing a satellite, wherein the container is configured to be coupled to or mounted on a launch vehicle for launching into space with the satellite housed therein.

The container may form an integral (e.g. structural or load-bearing) part of a launch vehicle (i.e. a vehicle having a part configured to carry a satellite into space) . For example, the container may be a snug fit inside a chamber within the launch vehicle. In another version, the body may form an exterior part of a launch vehicle. For example, the body may form an exterior part of the final stage of a multi-stage launch vehicle (e.g. a three- stage rocket) . The body may be configured to form the nose cone of a launch vehicle. The container may have a predetermined profile for engaging a corresponding profile of the launch vehicle (e.g. the profiles may define a standardised interface). In this way, a satellite manufacturer need only design their satellite to integrate with the container rather than with a launch vehicle. Since access to a launch vehicle may be severely restricted, the use of such a container should save time and cost, particularly since the manufacturer may keep the container on-site at all times during the development and manufacture of the satellite.

The container may be hermetically sealable to minimise contamination once the satellite is packaged therein. In this way, the use of pay-load clean room facilities at the launch site becomes largely redundant since there is no need to remove the satellite from the container prior to its installation on the launch vehicle.

The container may be further configured to release its satellite in dependence upon a predetermined event, e.g. an electrical signal from a control console on a launch vehicle or on the ground. Accordingly, the container may release its satellite automatically once the launch vehicle has reached a predetermined height .

The container may include an interface for operationally connecting the container with a launch vehicle, for example to allow information to pass between a launch vehicle and a container received therein. The container may also include means for coupling the container to a launch vehicle, and/or to couple a satellite to the container.

The body of the container may comprise a foamed material, for example polyurethane or polystyrene. The use of such a foamed casing may protect a satellite housed therein from shock or vibrational damage. The body may comprise a substantially incompressible external layer.

The body may comprise at least two parts which are moveable from an operative position, forming the chamber for housing a satellite, to an inoperative position wherein a satellite housed in the chamber may be discharged from the container. In this way, a satellite housed in the container may be entirely enclosed by the container until it is deployed.

The container may further include means for retaining the at least two parts in the operative position. The retaining means may comprise latch means, e.g. a spring bolt. The retaining means may be disengaged automatically in the response to an event (e.g. an electrical signal) .

The container may further comprise an inflatable member for sealing the chamber when the at least two parts are retained in the operating position. The inflatable member may be embedded in the body (e.g. between the at least two parts) . In addition to sealing the chamber, the inflatable member may be configured to expand upon inflation to urge the at least two parts apart when the retaining means are disengaged. In this way, the need for conventional explosive bolts may be dispensed with. The body may include a parachute for slowing decent of the container and an enclosed satellite when the container is ejected from a launch vehicle and the parachute is deployed. In this way, should a mission need to be aborted, the payload may return safely back to Earth. The parachute may be housed in a parachute compartment located in one part of the body (e.g. uppermost part when the satellite container is launched) . The uppermost part of the body may be aerodynamically shaped (e.g. domed or substantially cone shaped) to form a nose cone of a launch vehicle.

In accordance with a second aspect of the present invention, there is provided a satellite transportation module for use in a multi-stage launch vehicle configured to be coupled to or house a satellite container as hereinbefore described.

The module may, for example, be the final stage of a multi-stage launch vehicle (e.g. a three-stage rocket). The cargo chamber may be configured to be a snug fit around a satellite container received therein. In one version, the module may comprise a body defining a cargo chamber in which the whole or part of a satellite container is housed. For example, the body may comprise at least two parts which are moveable from an operative position, forming the cargo chamber for receiving a satellite container, to an inoperative position for discharging a satellite from the cargo chamber. In one embodiment, the at least two parts move in sympathy with the at least two parts of a satellite container contained in the cargo chamber.

In another version, the body may be configured such that the satellite container may be coaxially mounted on top of the body, at least when the vehicle is being launched. In this way, the satellite container may form a leading end (e.g. nose cone part) of the satellite transportation module.

The module may comprise an interface for operationally connecting a satellite to the module. The module may comprise means for coupling a satellite to the module. The coupling means may include a parachute for slowing decent of the coupling means and an attached satellite when the coupling means is ejected from the module and the parachute is deployed. In this way, should a mission need to be aborted, the payload may return safely back to Earth. Additionally, the coupling means may be connected to a motor unit (e.g. a 3^rd stage motor) which can fire to move the coupling means and an attached satellite away from a launch vehicle. The body may further comprise a structural, profile- defining shell or fairing comprising wood. For example, the shell may comprise a wood composite such as plywood or a plywood and balsa composite. It is believed that such a shell will provide the module with sufficient protection from dynamic heating during ascent. In addition, the body may be reinforced to withstand the high forces experienced during the ascent phase. The body may comprise foamed material, for example polyurethane or polystyrene, as a bulking agent to increase the rigidity of the structure. This concept also has the advantage of reducing the transmission of noise and vibration to the payload during launch. In accordance with a third aspect of the present invention, there is provided a module for a multi-launch launch vehicle, comprising a body having a structural, profile-defining shell comprising wood.

The shell may comprise a wood composite, for example plywood or a plywood and balsa composite. In addition, the body may be reinforced.

The body may comprise foamed material, for example polystyrene, as a bulking agent to increase the rigidity of the structure . The module may be the final stage of a multi-stage rocket (e.g. a three-stage rocket) .

BRIEF DESCRIPTION OF THE DRAWINGS An embodiment of the invention will now be described by way of example with reference to the accompanying drawings, in which:

Figure 1A is a schematic cross-sectional side view of a satellite container embodying the present invention in its closed position; Figure IB is a schematic cross-sectional side view of the satellite container of figure 1A in its open position;

Figure 1C is a schematic cross-sectional side view of a second satellite container embodying the present invention in its closed position;

Figure 2A is a schematic cross-sectional side view showing seal detail of the satellite container of figure 1A;

Figure 2B is a schematic cross-sectional side view showing seal detail of the satellite container of figure IB;

Figure 3 is a schematic cross-sectional view of the sealing mechanism employed in the satellite container of figures 2A and 2B; Figure 4A is a schematic cross-sectional side view of a 3^rd stage satellite transportation module incorporating the container of figure 1A;

Figure 4B is a schematic cross-sectional side view of the 3^rd stage satellite transportation module incorporating the container of figure IB;

Figure 5 illustrates the 3^rd stage satellite transportation module of figure 4A during an emergency operation;

Figure 6 is a schematic cross-sectional side view of a 2^nd stage module in combination with the 3^rd stage module of figure 4A;

Figure 7 is a schematic cross-sectional view of a 3- stage launch vehicle comprising the 2^nd and 3^rd stage modules of figures 4A and 5; and

Figure 8 is a schematic cross-sectional view of an engine which may be used in association with embodiments of the present invention. DETAILED DESCRIPTION OF SPECIFIC EMBODIMENTS

Figures 1A and IB show a micro-satellite container (10) comprising a body (12) , comprising first and second foamed parts (14,16) and an interface (18) for coupling the container (10) to a launch vehicle (not shown) . In Figure 1A the first and second foamed parts (14,16) are in their closed position, and define a chamber (20) for housing a micro-satellite (25) which may be releasably attached to the container by means of the interface (18) . Figure IB shows the container (10) with the first and second foamed parts (14,16) in their open position, thereby allowing the micro-satellite (25) to be released from the container. In use, the first and second foamed parts (14,16) are configured to move from their closed position to their open position automatically in response to a trigger mechanism. Figure 1C shows a second micro-satellite container (10') comprising a body (12'), comprising first and second foamed parts (14 ',16') and an interface (18') for coupling the container (10') to a second launch vehicle (not shown) . In their closed position, first and second foamed parts (14 ',16') define a chamber (20') for housing a micro- satellite (25') which may be releasably attached to the container by means of the interface (18 ' ) . The body further comprises a hard outer surface (13) which, in use, forms a leading exterior part of the launch vehicle. A parachute container (27) , which shares the hard outer surface (13), forms a nose cone of the launch vehicle.

Figures 2A and 2B show container (10) comprising separable first and second parts (14,16) defining a chamber

(20) , and a sealing mechanism (30) for sealing the chamber.

The sealing mechanism (30) comprises an inflatable member

(32), placed between the first and second parts (14,16), a spring bolt (34) attached to the first part (14) and a lockable member (36) attached to the second part (16) . Figure 2A shows the first and second parts (14,16) locked in their closed position, with the spring bolt (34) engaging the lockable member (36) . Figure 2B shows the first and second parts (14,16) in their unlocked, open position with the spring bolt (34) withdrawn from the lockable member (36) . When the first and second parts

(14,16) are locked in their closed position, the inflatable member (32) expands to form airtight seals between the first and second parts (14,16), thereby sealing the chamber (20) . However, once the first and second parts are unlocked, the inflatable member (32) continues to expand and urge the first and second parts (14,16) apart, thereby allowing the chamber contents (not shown) to be released unimpaired. Figure 3 shows the sealing mechanism (30) in more detail. The sealing mechanism (30) comprises an inflatable rubber member (32) , a gas cartridge (40) , spring bolts (34) each comprising a shoot bolt (35) and a spring (37) , a seal vent valve (42) , a one-way valve (44) and a fill/vent valve (46) . During operation, the first and second parts (not shown) are pushed together and pressurised gas is used to operate the shoot bolts (35) and inflate the inflatable rubber member (32) . To open the container (not shown) , the fill/vent valve (46) is opened (this can be operated electrically) to depressurise the shoot bolts (34'), whereupon the springs (37) disengage the shoot bolts (35) from the lockable member (not shown) to unlock the upper and lower parts. The same electrical signal additionally fires the gas cartridge (40) further inflating the inflatable rubber member (32) to urge the two parts apart. The gas cartridge (40) may be of the type commonly used to inflate car airbags. The seal vent valve would only be operated on the ground.

Figures 4A and 4B show a micro-satellite transportation module (50) comprising a body (52) defining a cargo chamber (54) configured to receive a micro- satellite container (10) . The module body (52) comprises first and second foamed parts (60,62), each comprising a wooden shell (64,66), and coupling means (68) for attaching the interface (18) of the micro-satellite container (10) to the module (50) . The module body (52) may further comprise means (not shown) for coupling the first and second foamed parts (60,62) to the first and second foamed parts (14,16) of the micro-satellite container (10) . The coupling means includes a combined 3^rd stage/escape motor (70) and a parachute system (72) . Figure 4A shows the first and second foamed parts (60,62) in their closed position, ready for take-off. The first and second foamed parts (60,62) may be locked together by means of automatically operable latched. Figure 4B shows the first and second foamed parts (60,62) in their open position. The first and second foamed parts (60,62) are moveable from their open position to their closed position in response to an electrical signal. In order that the micro-satellite (25) may be released from the, the first and second foamed parts (14,16) of the micro-satellite container (10) are coupled to the first and second foamed parts (60,62) prior to the opening of the latter. In this way, the micro-satellite

(25) and connected interface and coupling means may be released from the module once it has reached a desired height .

Figure 5 shows how the parachute system (72) may be deployed if it is necessary to discharge the micro- satellite (25) before the module has reached its intended height (e.g. if a mission is aborted) . In this situation, the first and second foamed parts (60,62) are jettisoned without the first and second foamed parts (14,16) of the micro-satellite container (10) coupling to the module (50) . Instead, the first and second foamed parts remain in their closed position, protecting the micro-satellite (25) . Once the first and second foamed parts (60,62) have been jettisoned, the 3^rd stage motor (70) fires to move the micro-satellite container away from the remaining module parts, whereupon the parachute system (72) deploys a parachute (75) which slows the decent of the micro- satellite container (10) and coupling means (68) towards the ground. The first and second foamed parts (14,16) of the micro-satellite container (10) protectively cushion the micro-satellite on landing. In this way, satellite components may be salvaged for future use. The foamed packaging surrounding the micro-satellite (25) may also allow the micro-satellite container (10) to float if it comes down in water. Figure 6 shows a 2^nd stage (80) of a three-stage launch vehicle, onto which a 3^rd stage micro-satellite transportation module (50) is attached. The 2^nd stage (80) comprises a support structure (82) and a single sustainer engine (84) , fed by a Hydrogen Peroxide tank (86) and a Kerosene Tank (88) . The 2^nd stage (80) includes motors (90), used for pitch and roll control, fed by high pressure gas cylinders (92) .

Figure 7 shows a complete three-stage launch vehicle (98) comprising 1^st stage (100) , 2^nd stage (80) and 3^rd stage (50) components. The 1^st stage comprises "strap-on" boosters which are discarded once their fuel load has been expended .

Figure 8 shows a low-pressure (pump fed) rocket engine (110) which may be used to propel the launch vehicle (98) . The engine (110) comprises a metal casing (112) lined with silica fibre in phenolic resin liners (114) and a carbon- carbon throat plug (116) . The engine further comprises a catalyst pack (118) and injector plate (120) , to be fed by tanks of hydrogen peroxide and kerosene (not shown) . The engine (110) is scalable and may be used in all stages of the launch vehicle (98) .

Claims

CLAIMS :

1. A satellite container for packaging a satellite during transportation thereof to a launch vehicle, comprising a body defining a chamber for housing a satellite, wherein the body is configured to be coupled to or mounted on a launch vehicle for carrying the body into space with the satellite housed therein.

2. A container according to claim 1, wherein the body is configured to release its satellite in dependence upon a predetermined event .

3. A container according to claim 1 or claim 2, further including an interface for operationally connecting the body with a launch vehicle.

4. A container according to any one of the preceding claims, further including means for coupling the body to a launch vehicle.

5. A container according to any of the preceding claims, wherein the body comprises a foamed material .

6. A container according to claim 5, wherein the body comprises polyurethane or polystyrene.

7. A container according to any of the preceding claims, wherein the body comprises a substantially incompressible external layer.

8. A container according to any one of claims 1 to 7, 5 wherein the body comprises at least two parts which are moveable from an operative position, forming the chamber for housing a satellite, to an inoperative position wherein a satellite housed in the chamber may be discharged from the container. 10

9. A container according to claim 8, further comprising means for retaining the at least two parts in the operative position.

15 10. A container according to claim 9, wherein the retaining means may be disengaged automatically.

11. A container according to claim 9 or claim 10, wherein the retaining means comprises latch means.

20

12. A container according to any one of claims 9 to 11, further comprising an inflatable member for sealing the chamber when the at least two parts are retained in the operating position.

25

13. A container according to claim 12, wherein the inflatable member is embedded in the body.

14. A container according to claim 12 or claim 13, wherein the inflatable member is configured to expand upon inflation to urge the at least two parts apart.

5 15. A satellite transportation module for use in a multistage launch vehicle, comprising a module body configured to be coupled to or house a satellite container, as previously defined in any of claims 1 to 14.

10 16. A module according to claim 15, wherein the module body defines a cargo chamber in which the satellite container is housed.

17. A module according to claim 16, wherein the cargo 15 chamber is configured to be a snug fit around a satellite container housed therein.

18. A module according to claim 16 or claim 17, wherein the module body comprises at least two parts which are

20 moveable from an operative position, forming the cargo chamber for receiving a satellite container, to an inoperative position for discharging a satellite from the cargo chamber .

25 19. A module according to claim 15, wherein the body is configured such that the satellite container is coaxially mounted on top of the body, at least when the vehicle is being launched.

20. A module according to any one of claims 15 to 19, further comprising an interface for operationally connecting a satellite container received by the module.

5

21. A module according to any one of claims 15 to 20, further comprising means for coupling a satellite to the module .

10 22. A module according to claim 21, wherein the coupling means includes a parachute for slowing decent of the coupling means and an attached satellite when the coupling means is ejected from the module and the parachute is deployed.

15

23. A module according to claim 21 or claim 22, wherein the coupling means is connected to a motor unit.

24. A module according to any one of claims 15 to 23, 20 wherein the module body comprises a structural, profile- defining shell comprising wood.

25. A module according to claim 24, wherein the shell comprises a wood composite.

25

26. A module according to claim 25, wherein the shell comprises plywood.

27. A module according to claim 26, wherein the shell comprises a balsa and plywood composite.

28. A module according to any one of claims 24 to 27, 5 wherein the module body is reinforced.

29. A module according to any one of claims 15 to 28, wherein the module body comprises foamed material.

10 30. A module according to claim 29, wherein the body comprises polyurethane or polystyrene.

31. A module according to any of claims 15 to 30, wherein the module is a final stage of a multi-stage rocket.

15

32. A module according to claim 31, wherein the module forms the final stage of a three-stage rocket.