Apparatus for producing a structure in space by radial extrusion of heated feestock

Apparatus (100) for use in space, the apparatus (100) comprising: a feedstock storage module (108) for storing a feedstock; a heating module (110) coupled to the feedstock storage module (108) and configured to heat the feedstock; an extrusion nozzle (112) coupled to the heating module (110) and configured to extrude heated feedstock from the apparatus (110); and one or more thrusters (118) configured to provide a propulsive force to the apparatus (100).

RELATED APPLICATIONS

This application is a national phase application filed under 35 USC § 371 of PCT Application No. PCT/GB2019/052399 with an International filing date of 28 Aug. 2019 which claims priority of GB Patent Application 1814043.4 filed 29 Aug. 2018 and EP Patent Application 18275135.4 filed 29 Aug. 2018. Each of these applications is herein incorporated by reference in its entirety for all purposes.

FIELD OF THE INVENTION

The present invention relates to apparatuses and methods for producing structures, and more particularly to the production, in space, of lenses for antennas.

BACKGROUND

Satellites, such as communications satellites, are used in many different applications including for television, telephone, radio, internet, and military applications. Such satellites may be in a geostationary orbit.

Placing a satellite in orbit, e.g. a geostationary orbit, tends to be costly and complex. Spacecraft tend to be highly limited by both launch volume and mass. When a spacecraft is launched from Earth, it undergoes significant forces which can cause systems on the spacecraft to become non-operational once in space.

SUMMARY OF THE INVENTION

The present inventors have realised that it is desirable to deploy large antennas in space, e.g. in an orbit such as a geostationary orbit. Such large antennas may be relatively narrow beam width, high gain antennas.

The present inventors have further realised that by producing or manufacturing large volume antennas in space, as opposed to on the Earth, lower spacecraft volume tends to be achievable. Furthermore, complex in-space antenna unfurling/unfolding operations may be avoided, thereby reducing the risk of parts failure.

In a first aspect, the present invention provides an apparatus for use in space. The apparatus comprises a feedstock storage module for storing a feedstock, a heating module coupled to the feedstock storage module and configured to heat the feedstock, an extrusion nozzle coupled to the heating module and configured to extrude heated feedstock from the apparatus, and one or more thrusters configured to provide a propulsive force to the apparatus.

In a further aspect, the present invention provides an apparatus for producing an object in space, the apparatus comprising: a feedstock storage module for storing a feedstock; a heating module coupled to the feedstock storage module and configured to heat the feedstock; an extrusion nozzle coupled to the heating module and configured to extrude heated feedstock from the apparatus; one or more thrusters configured to provide a propulsive force to the apparatus; and a controller configured to control the one or more thrusters so as to control a shape of the object.

In any aspect, the apparatus may further comprise a receiver and/or a transmitter. The receiver and/or the transmitter may each be moveable with respect to the extrusion nozzle such that a distance between the receiver and/or the transmitter and the extrusion nozzle may be varied.

The one or more thrusters may be operable to rotate and/or translate the apparatus for use in space. The apparatus may be elongate (e.g. substantially cylindrical) having a longitudinal axis. The one or more thrusters may be operable to rotate the apparatus about the longitudinal axis and/or translate the apparatus in a direction along the longitudinal axis.

The extrusion nozzle may be a radially extending extrusion nozzle. The apparatus may further comprise a further extrusion nozzle coupled to the heating module and configured to extrude heated feedstock from the apparatus. The further extrusion nozzle may be located opposite to the extrusion nozzle and extends in an opposite direction to the extrusion nozzle.

The apparatus may further comprise collection means for retaining material extruded from the extrusion nozzle proximate to the apparatus. The collection means may comprise a robot arm having, as an end effector, a gripper.

The apparatus may further comprise a robot arm having an end effector, the end effector comprising welding means.

The apparatus may be arranged for launch delivery into space.

In a further aspect, the present invention provides a method of producing a structure by an apparatus. The apparatus comprises a feedstock storage module, a heating module, an extrusion nozzle, and one or more thrusters. The method comprises: providing, from the feedstock storage module, feedstock to the heating module; heating, by the heating module, the received feedstock; extruding, from the extrusion nozzle, the heated feedstock; and, while the heated feedstock is being extruded from the extrusion nozzle, providing, by the one or more thrusters, a propulsive force to the apparatus, thereby to cause the apparatus to move.

In a further aspect, the present invention provides a method of producing a structure by an apparatus, the apparatus comprising a feedstock storage module, a heating module, an extrusion nozzle, and one or more thrusters, the method comprising: providing, from the feedstock storage module, feedstock to the heating module; heating, by the heating module, the received feedstock; extruding, from the extrusion nozzle, the heated feedstock; and, while the heated feedstock is being extruded from the extrusion nozzle, providing, by the one or more thrusters, a propulsive force to the apparatus, thereby to cause the apparatus to move; wherein the one or more thrusters are controlled so as to control a shape of the object being produced.

While the heated feedstock is being extruded from the extrusion nozzle, the one or more thrusters may cause the apparatus to rotate, whereby the structure may have a spiral shape. While the heated feedstock is being extruded from the extrusion nozzle, the one or more thrusters may cause the apparatus to translate, whereby the structure may have a conical helix shape.

While the heated feedstock is being extruded from the extrusion nozzle, the one or more thrusters may cause the apparatus to rotate, whereby to cause the structure to have a spiral shape. While the heated feedstock is being extruded from the extrusion nozzle, the one or more thrusters may cause the apparatus to translate, whereby to cause the structure to have a conical helix shape.

In a further aspect, the present invention provides a method of transmitting or receiving a radio signal. The method comprises: producing a structure by an apparatus according to the method of any preceding aspect, wherein the apparatus further comprises a transmitter or a receiver; and, using the produced structure as a lens, transmitting or receiving a radio signal by the transmitter or the receiver respectively.

DETAILED DESCRIPTION

FIG.1is a schematic illustration (not to scale) of an embodiment of an apparatus, hereinafter referred to as “the antenna apparatus”100.

The antenna apparatus100is used, in space (e.g. in an orbit such as a geostationary orbit), to produce a lens and, in combination with the produced lens, function as an antenna.

The antenna apparatus100is generally cylindrical in shape. The antenna apparatus100is elongate. A longitudinal axis of the antenna apparatus100is indicated inFIG.1by the reference numeral101. The antenna apparatus100comprises a manufacturing and power module102, a systems control module104, and a transceiver module106.

The manufacturing and power module102is generally cylindrical in shape. The systems control module104is generally cylindrical in shape. The transceiver module106is generally cylindrical in shape.

The manufacturing and power module102is located at a first end of the generally cylindrical antenna apparatus100. The transceiver module106is located at a second end of the generally cylindrical antenna apparatus100, the second end being opposite to the first end. The systems control module104is disposed between the manufacturing and power module102and the transceiver module106.

In this embodiment, the manufacturing and power module102comprises a feedstock storage module108, a heating module110, an extrusion nozzle112, and a solar array114.

The feedstock storage module108contains one or more raw materials from which an antenna lens is to be produced. Such raw materials are hereinafter referred to as a “feedstock”. In this embodiment, the feedstock is a metal or alloy (e.g. copper or a different electrically conductive material) in powder form. The feedstock storage module108is coupled to the heating module110and is configured to supply the feedstock to the heating module110. Operation of the feedstock storage module108may be controlled by the systems control module104.

The heating module110is configured to heat the feedstock received from the feedstock storage module108, thereby to melt the received feedstock. The heating module110is coupled to the extrusion nozzle112. The heating module110may be configured to force the molten feedstock through the extrusion nozzle112. Operation of the heating module110may be controlled by the systems control module104.

The extrusion nozzle112extends radially outwards from the substantially cylindrical body of the manufacturing and power module102. The extrusion nozzle112is configured to receive molten feedstock from the heating module110. The heating module110and/or the extrusion nozzle112and/or other means is configured to force the molten feedstock through the extrusion nozzle112, and out of an opening or orifice at a distal end of the extrusion nozzle112.

The extrusion nozzle112may be fixed, i.e. immovable, relative to the substantially cylindrical body of the manufacturing and power module102. In other words, the extrusion nozzle112may have a fixed position relative to the body of the apparatus100. Thus, in this embodiment, the extrusion nozzle112is configured to extrude material in only a single direction relative to the apparatus, that being in a radial direction.

The extrusion nozzle112is configured to cool the molten feedstock as the molten feedstock moves through the extrusion nozzle112, thereby to solidify the feedstock. The solidified feedstock is extruded from the distal end of the extrusion nozzle112in a radially outwards direction thereby to form a lens, as described in more detail later below with reference toFIG.2.

In this embodiment, the cooling and solidification of the feedstock as it is forced through the extrusion nozzle112may be caused by exposure of the extrusion nozzle112to the operating environment of the antenna apparatus100(e.g. outer space). Nevertheless, the extrusion nozzle112may be cooled over at least a part of its length by cooling means, e.g. a cooling sleeve. The length of the extrusion nozzle112may be designed to provide a predetermined cooling rate for the molten feedstock.

Operation of the extrusion nozzle112may be controlled by the systems control module104.

The solar array114is configured to convert incident sunlight into electricity. The solar array114may be a photovoltaic system. The solar array114is coupled to other components of the antenna apparatus100. For example, the solar array114may provide electrical power to one or more components selected from the group of components comprising the feedstock storage module108, the heating module110, the extrusion nozzle112, the systems control module104, and the transceiver module106.

In this embodiment, the systems control module104comprises a controller116and a plurality of thrusters118.

The controller116is configured to control operation of other components of the antenna apparatus100. For example, the controller116may control one or more components selected from the group of components comprising the feedstock storage module108, the heating module110, the extrusion nozzle112, the solar array114, the plurality of thrusters118, and the transceiver module106. The controller116may receive power from the solar array114.

The plurality of thrusters118are comprised within a reaction control system (RCS) of the antenna apparatus100. The thrusters118are operable to provide attitude control of the antenna apparatus100in space. In other words, the thrusters118may be used to control the orientation of the antenna apparatus100in space with respect to, e.g., an inertial frame of reference or another entity such as the Earth. The thrusters118are operable to provide translation control of the antenna apparatus100in space.

FIG.2is a schematic illustration (not to scale) illustrating the production, in space, of a lens200by the antenna apparatus100.FIG.2shows the antenna apparatus100when viewed from the first end of the antenna apparatus100, along the longitudinal axis101of the antenna apparatus100.

In this embodiment, the controller116controls the manufacturing and power module102to extrude solidified molten feedstock (i.e. a metal) via the extrusion nozzle112, in the direction of arrow201, thereby to form the lens200. In this embodiment, the lens200is a diffractive lens, e.g. a Spiral Zone Plate diffractive lens. The lens200, i.e. the solidified feedstock, is extruded radially. The lens200is an elongate, electrically conductive member, e.g. a wire. At and proximate to the point at which the lens200exits the extrusion nozzle112, the lens200is malleable. The controller116may control, e.g. based on a temperature of the operating environment of the apparatus100, the heating and cooling of the feedstock by the manufacturing and power module102to provide that the lens200is malleable where it exits the extrusion nozzle112.

The controller116controls the RCS, including the plurality of thrusters118, to cause the antenna apparatus100to rotate about its longitudinal axis101as the lens200is extruded from the extrusion nozzle112. This rotation is indicated inFIG.2by arrows and the reference numeral202.

The rotation of the antenna apparatus100about its longitudinal axis101causes the malleable portion of the lens200to bend. More specifically, a difference in inertia between the extruded lens200and the antenna apparatus100may cause the malleable portion of the lens200(i.e. a recently extruded portion of the lens200proximate to the opening of the extrusion nozzle112) to bend. Thus, the lens200is formed into a spiral shape centred about the longitudinal axis.

The material extruded by the extrusion nozzle112is extruded directly into space, outside the apparatus, whereby it is cooled and hardens.

In this embodiment, the spiral lens200is formed on a flat plane.

FIG.3is a schematic illustration (not to scale) showing the antenna apparatus100and the lens200in use as a receiving antenna.

In this embodiment, the transceiver module106is coupled to the other components of the apparatus100via an extendible arm300. In particular, the transceiver module106is attached to the systems control module104via the extendible arm300. The extendible arm300may be controlled, e.g. by the controller116, so as to vary its length. Thus, the distance between the transceiver module106and the systems control module104may be varied. Thus, the distance between the transceiver module106and the lens200may be varied. The extendible arm300may, for example, be a telescopic arm.

In this embodiment, radio waves302are incident on the lens200. The radio waves302may have been transmitted from an Earth-based transmitter. The lens200focuses the incident radio waves302onto the transceiver module106, e.g. through phase shift and diffraction. The transceiver module106comprises a transceiver configured to receive the radio waves302focused onto it by the lens200. Thus, the radio waves302are received by the antenna formed by the antenna apparatus100and the lens200.

In this embodiment, the controller116is configured to control the extendible arm300to position the transceiver module106at a focal point of the lens200. This positioning of the transceiver module106by the controller116may be performed using, for example, one or more properties of the lens200(such as a diameter or pitch of the lens200) and/or one or more properties of the antenna apparatus100(such as an orientation) and/or one or more properties of the radio waves302(such as frequency or wavelength). The properties of the lens200used to position the transceiver module106may be measured by the antenna apparatus100, or may be determined or inferred by the controller116based on the production of the lens200. The properties of the radio waves302may be measured by the antenna apparatus100, or may be predetermined.

The antenna apparatus100and the lens200may be used as a transmitting antenna. For example, the transceiver module106may include a transmitter configured to send an electrical signal to the lens200, which is then transmitted as radio waves by the lens200.

Thus, an antenna module100which may be used to produce (e.g. in space) a lens200and function as an antenna is provided.

Advantageously, the lens of the above described antenna is fabricated or produced when the antenna module is in space. The volume of the antenna module is lower than that of the in-space antenna (i.e. the antenna apparatus and the lens). Thus, a reduced volume for launch into space is provided. This tends to reduce launch cost.

Furthermore, since the lens is only produced once the antenna apparatus is in space, the likelihood of damage to the lens (e.g. caused by the forces experienced during launch) tends to be reduced or eliminated.

The above described apparatus tends to avoid the use of complex in-space antenna unfurling/unfolding operations.

Advantageously, the above described apparatus tends to allow for the placement of larger antennas in space than can be achieved conventionally.

In the above described methods and apparatus, the shape of the formed object (e.g. the antenna) is defined by movement of the apparatus in space. In some embodiment, the shape of the object may be controlled only by controlling movement (i.e. translation and/or rotation) of the apparatus in space.

In the above embodiments, the lens is formed on a flat plane. However, in other embodiments, the lens is not formed on a flat plane. For example, the lens may be formed about an axis so as to produce a spiral, conical lens, a parabolic reflector, or a helical antenna.

By way of example,FIG.4is a schematic illustration (not to scale) illustrating the production, in space, of a further lens400by the antenna apparatus100.

In this embodiment, the controller116controls the manufacturing and power module102to extrude solidified molten feedstock (i.e. a metal) via the extrusion nozzle112, thereby to form the further lens400. In the same way as for the lens200described in more detail earlier above with reference toFIGS.2and3, as the further lens400is extruded from the extrusion nozzle112, the plurality of thrusters118are controlled to cause the antenna apparatus100to rotate about its longitudinal axis101. This rotation causes the further lens200to form a spiral shape centred about the longitudinal axis101. In addition, in this embodiment, the plurality of thrusters118are controlled to cause the antenna apparatus100to undergo translational movement, i.e. to move in a direction along the longitudinal axis101, as indicated inFIG.4by an arrow and the reference numeral402. This movement of the antenna apparatus100in a direction along the longitudinal axis101causes the malleable portion of the further lens400to bend in an opposite direction along the longitudinal axis101. More specifically, a difference in inertia between the extruded lens400and the antenna apparatus100may cause the malleable portion of the lens400(i.e. a recently extruded portion of the lens400proximate to the opening of the extrusion nozzle112) to bend in a direction along the longitudinal axis101. Thus, the further lens400is formed into conic helix about the longitudinal axis101. The further lens400defines a curved surface indicated inFIG.4by a dotted line and the reference numeral404. The further lens400may be used as a parabolic reflector.

In the above embodiments, the produced lens remains attached to the antenna module. However, in other embodiments, once produced by the manufacturing and power module, a lens may be detached from the antenna module, e.g. detached from the end of the extrusion nozzle thereby to allow another lens to be produced. In some embodiments, a lens that is detached from the antenna module may be used by a different entity (e.g. a space-based entity remote from the antenna module). In some embodiments, a structure (e.g. a lens) that is detached from the extrusion nozzle may be collected or retained by a different component of the antenna module. For example, with reference again toFIG.1, the antenna module may include collection means121, such as a gripper arm or a magnet121, for collecting a produced and detached lens, and retaining the detached lens proximate to the antenna module.

Thus, the antenna module may be implemented to produce a plurality of lenses or other structures. In some embodiments, the plurality of lenses or structures produced by the antenna module may be coupled together, thereby to produce lens having different properties.

By way of example,FIG.5is a schematic illustration (not to scale) illustrating a second further lens500constructed from a plurality of spiral structures501,502. (The spiral structures501,502may themselves be lenses.)

In this embodiment, the second further lens500is constructed by the antenna module as follows.

Firstly, a plurality of relatively small spiral structures501are produced. The small spiral structures501are produced one after the other by the antenna module100, each small spiral structure501being detached from the extrusion nozzle112before a subsequent small spiral structure501is produced. The small spiral structures501may be collected by the antenna module100after being produced. The small spiral structures501may each be produced in a similar way to that described above for the lens200or the further lens400. The small spiral structures501may be substantially identical to each other.

Secondly, a relatively large spiral structure502is produced. The large spiral structure502may remain attached to the antenna module100, e.g. to the end of the extrusion nozzle112. The large spiral structure502may be produced in a similar way to that described above for the lens200or the further lens400.

Thirdly, the small spiral structures501are attached to the large spiral structure502at different respective locations on the large spiral structure502. The small spiral structures501may be spaced apart (e.g. equally spaced apart) along a circle centred about the centre of the large spiral structure502. The small spiral structures501may be attached to the large spiral structure502by any appropriate means. For example, the antenna module100may comprise a robot arm122comprising an end effector, the end effector having welding means for welding the small spiral structures501to the large spiral structure502. The robot arm122and end effector may be controlled by the controller116.

Thus, the antenna module100may produce the second further lens500.

In the above embodiments, the lenses and structures produced by the antenna module are spiral in shape. However, in other embodiments, the antenna module may produce a lens or structure having a different shape, i.e. a shape other than a spiral. The controller may control the RCS, including the plurality of thrusters, to move the antenna apparatus so as to produce a structure having a desired shape. Such movement of the antenna apparatus may include rotation (e.g. roll, pitch, and yaw) and translation (e.g. along three mutually orthogonal axes, x, y, and z, one of which may be the longitudinal axis of the antenna module).

By way of example,FIG.6is a schematic illustration (not to scale) illustrating a third further lens600constructed from a plurality of sub-structures601,602. (The sub-structures601,602may themselves be lenses.)

In this embodiment, the third further lens600is constructed by the antenna module100as follows.

Firstly, a first sub-structure601is produced. The first sub-structure601is an elongate, wavy structure. The first sub-structure601may be produced by the controller116controlling the antenna module100to move back and forth along the longitudinal axis101as material is extruded from the extrusion nozzle112. The antenna module100may be controlled so as not to rotate. The first sub-structure601may be detached from the antenna module100after it has been formed. The first sub-structure601may be collected by the antenna module100after being produced.

Secondly, a second sub-structure602is produced. The second sub-structure602may be substantially identical to the first sub-structure601, and may be produced in the same way.

Thirdly, the first sub-structure601is attached to the second sub-structure602. The first and second sub-structures602may be attached together so that they have different orientations, e.g. such that they are substantially orthogonal. The first and second sub-structures602may be attached together by any appropriate means, for example using the above-mentioned robot arm comprising an end effector having a welding means.

Thus, the antenna module100may produce the third further lens600.

In the above embodiments, the feedstock is a metal or alloy. However, in other embodiments, the feedstock is a different material, for example an electrically conductive plastic.

In the above embodiments, the feedstock is in powder form. However, in other embodiments, the feedstock is in a different form other than a powder. For example, the feedstock may be a wire or a solid block of material.

In embodiments, the antenna module comprises a single extrusion nozzle. However, with reference again toFIG.1, in other embodiments, the antenna nozzle100comprises a plurality of extrusion nozzles112,120from which material may be extruded to form a plurality of structures, e.g. lenses. The multiple extrusion nozzles112,120may be controlled to extrude material in parallel (i.e. simultaneously) or in series. In some embodiments, two extrusion nozzles112,120are located at opposite sides of the antenna module. This advantageously tends to provide that, when the two opposing extrusion nozzles112,120are controlled to extrude material at the same time, forces exerted on the antenna module100as a result of the extrusion tend to balance, thereby providing improved stability of the antenna module100, e.g. without a need for any additional mechanical intervention. Preferably, extrusion nozzles are arranged around the apparatus in directly opposing pairs112,120. For example, in the case of a cylindrical apparatus, one or more pairs of extrusion nozzles112,120may be present, each pair of extrusion nozzles112,120being diametrically opposed each other. This advantageously tends to balance the system e.g. to allow mesh extrusions to be produced with desired radius of curvature, and e.g. to allow each spiral of extruded material to overlap to create the mesh.

In the above embodiments, the one or more extrusion nozzles are located at or proximate to one end of the apparatus. However, in other embodiments, the one or more extrusion nozzles are located at a different position on the apparatus. Preferably, one or more of the extrusion nozzles (more preferably all of the extrusion nozzles) are located at or proximate to a centre of gravity of the apparatus. For example, the extrusion nozzles may be substantially aligned with the centre of gravity of the apparatus along a longitudinal axis of the apparatus. This advantageously tends to reduce or eliminate any unwanted motion during extrusion of the antenna, which could cause the extruded object to deviate from the desired shape. This may also reduce undesired motion of the cylindrical apparatus.

In the above embodiments, the antenna module is substantially cylindrical in shape. However, in other embodiments, the antenna module has a different shape.

In the above embodiments, the antenna module comprises an extendible arm. However, in other embodiments, the extendible arm is omitted.

In the above embodiments, the antenna module comprises a transceiver module which includes a transmitter and a receiver (e.g. a transceiver). However, in other embodiments, the transceiver module is omitted. In some embodiments, the antenna module comprises only a transmitter and not a receiver. In some embodiments, the antenna module comprises only a receiver and not a transmitter.

In the above embodiments, the antenna module comprises a solar array. However, in other embodiments, the solar array is omitted. In some embodiments, the antenna module comprises a different power source instead of or in addition to the solar array. In some embodiments, the antenna module comprises one or more batteries for providing power on the antenna module.