Single-actuator rotational deployment mechanism for multiple objects

A deployment system, such as for deploying wings, includes a pair of hub assemblies that transmit linear motion provided by an actuator into a combination of rotational and axial motion. The actuator works on both hub assemblies, rotating (for each wing) a slew ring that is coupled to a lift bar that acts as a follower, following a pair of cam slots, to allow the wings to follow their desired course. In one embodiment the wings move axially away from a fuselage at the beginning of the deployment movement, followed by a primarily rotational movement, with the wings pulling in toward the fuselage at the end of the deployment process. The actuator includes a pair of threaded shafts (threaded in opposite directions) that rotate along with a pinion gear, driven by a motor, to translate a pair of retractor links that are coupled to the slew rings.

FIELD OF THE INVENTION

The invention is in the field of deployment mechanisms, such as for wings.

DESCRIPTION OF THE RELATED ART

Until recently, most bombs were of the unguided, gravity type. The bomb was aimed by the motion of the aircraft on which it was carried and which flew approximately over the target. The bomb was released from a location on the flight path estimated to cause the bomb to fall onto its target. After the bomb was dropped there was no control over its motion. The result was that the aircraft was exposed to defensive measures over the target for an extended period of time in a flight path that was required to be straight and level, and the accuracy of the bombing was always somewhat problematic.

Recent developments improved upon this type of earlier munition in important ways. Wings were affixed to the bomb so that it could be dropped at a distance from the target of many miles and would glide to its target. The bomber aircraft consequently had far less exposure to defensive measures. The glide bomb was also provided with movable control surfaces and a guidance system, typically based upon cooperation with a laser designator, an inertial navigation system, or the global positioning system. The guidance capability greatly improved the accuracy of the bombing and reduced collateral damage.

The flight distance of a glide bomb depends upon several factors, one of which is the length of the wings. Long, slender wings result in long glide distances. However, long, slender wings take up a great deal of space in the bomb deployment racks on the launching aircraft. It has therefore become an established practice to fold the wings to a folded position along the fuselage of the glide bomb for storage, and then to pivot the wings to an open, deployed position when the bomb is dropped.

However, even this approach is not fully satisfactory in that it does not permit optimal-length and optimal-performance wings to be used with many types of bombs. There is accordingly a need for an improved approach to glide bombs and other types of winged weapons such as some types of powered missiles, which further improves their aerodynamic performance.

Many other wing deployment mechanisms have been tried previously, such as by deploying wings from internal slots in a fuselage.

One example of a prior approach is that described in U.S. Pat. No. 7,185,847, which involves a winged vehicle includes an elongated fuselage, and a wing mechanism affixed to the fuselage. The wing mechanism has a wing-support-body track affixed to and extending lengthwise along the fuselage, a translating wing-support body engaged to and translatable along the wing-support-body track, and exactly two deployable cantilevered wings. Each deployable cantilevered wing has a wing pivot mounted to the translating wing-support body so that the deployable cantilevered wing is pivotable about the translating wing-support body. The two deployable cantilevered wings are each pivotable between a stowed position and a deployed position.

SUMMARY OF THE INVENTION

A wing deployment system includes a single actuator moving both wings from a stowed state to a deployed state, using a combination of rotation and axial movement (in the direction of the axis of the rotation). This provides deployment simultaneously in a manner that is symmetric (balanced), and that minimizes aerodynamic disturbance, and further allows the wings to be located outside of an air vehicle fuselage. Having the wings external to the fuselage frees up volume within the fuselage, for example for use in carrying additional fuel or payload items. In addition the compact size and efficient operation, such as with a reduced part count and complexity, provides an advantage over prior approaches.

A deployment system includes a single actuator moving a pair of objects to be deployed from a stowed state to a deployed state, using a combination of rotation and axial movement (in the direction of the axis of the rotation).

According to an aspect of the invention, a deployment mechanism or system includes: a mount configured to receive a device to be deployed; a hub assembly that includes a tube having a cam slot; and an actuator configured to rotate the mount relative to the tube; wherein when the actuator causes the mount to rotate relative to the tube, a follower engaging the cam slot causes the mount to move both axially and rotationally relative to the tube.

According to an embodiment of any paragraph(s) of this summary, the follower is part of a bar that passes through the hub assembly.

According to an embodiment of any paragraph(s) of this summary, the cam slot is a first cam slot; and the tube includes a second cam slot diametrically opposed to the first cam slot.

According to an embodiment of any paragraph(s) of this summary, the cam slots are J-shape cam slots.

According to an embodiment of any paragraph(s) of this summary, each of the cam slots a terminus of the cam slot is substantially axial in orientation.

According to an embodiment of any paragraph(s) of this summary, each of the cam slots the terminus has a reduced width, providing less clearance about the follower than other portions of the cam slot.

According to an embodiment of any paragraph(s) of this summary, circular cross-section ends of the bar engage the cam slots.

According to an embodiment of any paragraph(s) of this summary, the bar has a rectangular cross-section center portion that is between the circular cross-section ends.

According to an embodiment of any paragraph(s) of this summary, the tube is an outer tube.

According to an embodiment of any paragraph(s) of this summary, the hub assembly further includes an inner tube within the outer tube, wherein the inner tube is connected to the mount and moves along with the mount.

According to an embodiment of any paragraph(s) of this summary, the center portion of the bar engages diametrically-opposed rectangular openings in the inner tube.

According to an embodiment of any paragraph(s) of this summary, the hub assembly further includes a tension rod located along a central axis of the hub assembly, wherein the tension rod mechanically engages the inner tube and the mount.

According to an embodiment of any paragraph(s) of this summary, the tension rod includes a rectangular window therethrough that receives and engages the center portion of the bar.

According to an embodiment of any paragraph(s) of this summary, the hub assembly further includes a tension rod located along a central axis of the hub assembly, wherein the tension rod mechanically engages the inner tube and the mount.

According to an embodiment of any paragraph(s) of this summary, the tension rod has opposite first and second threaded ends.

According to an embodiment of any paragraph(s) of this summary, the first threaded end has a pair of nuts thereon that bear on opposite major surfaces of a platform that is within the inner hub.

According to an embodiment of any paragraph(s) of this summary, the second threaded end threadedly engages the mount.

According to an embodiment of any paragraph(s) of this summary, the tension rod has a spring therearound that provides a biasing force between the inner hub and the mount.

According to an embodiment of any paragraph(s) of this summary, the system further includes a slew ring that is mechanically coupled to the actuator such that the actuator selectively rotates the slew ring about the hub assembly.

According to an embodiment of any paragraph(s) of this summary, the follower is part of a bar that passes through the hub assembly.

According to an embodiment of any paragraph(s) of this summary, the system further includes walking links that mechanically couple the slew ring to the bar.

According to an embodiment of any paragraph(s) of this summary, the slew ring, the walking links, and the bar all rotate as a unit about a central axis of the hub assembly.

According to an embodiment of any paragraph(s) of this summary, the walking links have ball-and-socket connections with the slew ring.

According to an embodiment of any paragraph(s) of this summary, the walking links have cross-joint connections with ends of the bar.

According to an embodiment of any paragraph(s) of this summary, the system further includes bearings between the slew ring and the hub assembly.

According to an embodiment of any paragraph(s) of this summary, the actuator includes a threaded shaft, driven by a motor, that when the shaft is turned moves along the shaft a link tube that is coupled to the slew ring.

According to an embodiment of any paragraph(s) of this summary, the actuator is a ball screw actuator, and wherein the ball screw actuator further includes a ball screw nut that is attached to the link tube, and that moves along the shaft along with the link tube.

According to an embodiment of any paragraph(s) of this summary, the actuator further includes gearing between a motor shaft of the motor, and the threaded shaft.

According to an embodiment of any paragraph(s) of this summary, the gearing includes a spur gear having at least 120 teeth.

According to an embodiment of any paragraph(s) of this summary, the actuator further includes a motor brake for selectively preventing the motor from turning a motor shaft of the motor.

According to an embodiment of any paragraph(s) of this summary, the slew ring includes a detent mechanism for locking the deployment mechanism in place.

According to an embodiment of any paragraph(s) of this summary, the system further including a frame to which the hub assembly is attached and to which the actuator is mechanically coupled.

According to an embodiment of any paragraph(s) of this summary, the actuator is mechanically coupled to the frame by a hinge connection.

According to an embodiment of any paragraph(s) of this summary, the mount is a first mount; the hub assembly is a first hub assembly; and further including: a second mount configured to receive a second device to be deployed; and a second hub assembly that includes a second hub having a second cam slot; wherein the actuator is configured to rotate the second mount relative to the second hub; and wherein when the actuator causes the second mount to rotate relative to the second hub, a second follower engaging the second cam slot causes the mount to move both axially and rotationally relative to the hub.

According to an embodiment of any paragraph(s) of this summary, the actuator is configured to rotate the first mount and the second mount in opposite directions.

According to an embodiment of any paragraph(s) of this summary, the actuator includes a pair of ball screw actuators, driven by a motor through a common reduction gear set.

According to an embodiment of any paragraph(s) of this summary, the deployment system is a wing deployment system used to deploy wings that are attached to the mounts.

According to an embodiment of any paragraph(s) of this summary, the wing deployment system is part of an aerial vehicle.

According to another aspect of the invention, an actuator includes: a motor; gearing operatively coupled to the motor, wherein the gearing includes a pinion gear; a pair of threaded shafts attached to and rotating with the spur gear; and a pair of retractor links that move along respective of the threaded shafts as the spur gear is turned by the motor; wherein the threaded shafts are threaded in opposite orientations relative to each other, such that the retractor links move in opposite directions along the threaded shafts.

According to an embodiment of any paragraph(s) of this summary, each of the retractor links includes: a ballscrew nut that threadedly engages one of the threaded shafts; and a hollow link tube attached to the ballscrew nut, with the link tube receiving the one of the threaded shafts therein.

According to another aspect of the invention, a method of deploying wings of an aerial vehicle includes: using an actuator to turn a pair of wing mounts coupled to respective hub assemblies, wherein hub assemblies include respective cam followers that follow cam slots, to move the wing mounts in both axial and rotational directions, and thereby move the wings, which are coupled to respective of the wing mounts.

According to an embodiment of any paragraph(s) of this summary, the wings have an initial axial movement away from a fuselage of the aerial vehicle, and are pulled axially in toward the fuselage as the wings are deployed.

DETAILED DESCRIPTION

A deployment system, such as for deploying wings, includes a pair of hub assemblies that transmit linear motion provided by an actuator into a combination of rotational and axial motion. The actuator works on both hub assemblies, rotating (for each wing) a slew ring that is coupled to a lift bar that acts as a follower, following a pair of cam slots, to allow the wings to follow their desired course. In one embodiment the wings move axially away from a fuselage at the beginning of the deployment movement, followed by a primarily rotational movement, with the wings pulling in toward the fuselage at the end of the deployment process. The actuator includes a pair of threaded shafts (threaded in opposite directions) that rotate along with a spur gear, driven by a motor, to translate a pair of retractor links that are coupled to the slew rings. The retractor links may include ballscrew mechanisms that engage the threaded shafts. The use of a single actuator to deploy both wings simultaneously provides symmetry in the deployment. The actuator may be mounted on a hinge mechanism to allow it to shift position during the deployment.

Referring initially toFIGS.1and2, an aircraft10, such as an unmanned aerial vehicle (UAV) or missile (e.g., a cruise missile), includes a deployment system or mechanism12, for deploying a pair of wings14and16.FIG.1shows the wings14and16in a stowed position, outside and along an outer surface of a fuselage20of the aircraft10.FIG.2shows the wings14and16in a deployed position. The use in the aircraft10is only one example of how the deployment system12may be employed, and such a system may be used to deploy or move other sorts of devices.

FIG.3shows further details of the deployment system12. The system12includes a pair of wing mounts24and26to which the wings14and16(FIG.1) are coupled. The wing mounts24and26are mechanically coupled to parts of a pair of hub assemblies34and36. An actuator40is used to rotate parts of the hub assemblies about central axes44and46of the hub assemblies34and36, as well as to move parts of the hub assemblies in an axial direction.

This movement by parts of the hub assemblies34and36causes the same movement by the wings14and16(FIG.1). In one example the wings14and16are initially moved axially to create clearance from the fuselage20(FIG.1), and are also move rotationally to the deployed position. This rotational movement is accompanied by an axial movement during the travel of the wings14and16, to bring the wings14and16into the fuselage20when the wings14and16reach the deployed positions. Bringing the wings14and16in closer to the fuselage20may improve aerodynamics of the aircraft10.

The deployment of the wings14and16may be part of a launch process of the aircraft10. The wings14and16being in a stowed condition may allow the aircraft to be launched in a compact configuration, with the wings14and16being deployed in the initial stages of flight.

A frame50secures both of the hub assemblies34and36. The actuator40is mechanically coupled to the frame50through a hinge52, which allows some relative movement of the actuator40relative to the frame50. The frame50is itself secured to structure of the aircraft10(FIG.1).

FIG.4shows additional details of the frame50. The frame50may be made of aluminum or another suitable material, such as steel or titanium. The frame50includes a pair of linking members58and60, at an angle to one another, that separate and support a pair of curved ends64and66, which have recesses for receiving the hub assemblies34and36(FIG.2). The curved ends64and66each have mounting holes70for receiving fasteners, such as bolts or rivets, for securing the hub assemblies34and36to the frame50. There may also be protrusions72at the ends64and66, for engaging corresponding recesses in the hub assemblies34and36.

FIGS.5-7show details of one of the hub assemblies, the hub assembly34. The hub assembly36(FIG.3) may have similar features, and may be substantially identical to the hub assembly34. The hub assemblies34and36may be configured so as to be symmetric (mirror images) across a center plane of the aircraft10(FIG.1) and the frame50(FIG.3). The hub assembly34includes an outer tube80and an inner tube82. The outer tube80is fixed to the frame50(FIG.4), and the inner tube82moves along with the wing14, so the inner tube82is able to slide and rotate relative to the outer tube80.

The outer tube80includes recesses86for receiving the protrusions72(FIG.4) of the frame50(FIG.4). The outer tube80also has fastener holes88that line up with the frame's mounting holes70(FIG.4), for receiving fasteners to secure the hub assembly34to the frame50.

The outer tube80also has a pair of cam slots90therein, with the cam slots90being diametrically opposed 180 degrees apart from one another on opposite sides of the outer tube80. The cam slots90are used to guide the inner tube82and the parts that are attached to it (the mount24and the wing14), during the deployment. The cam slots90may have any of a variety of suitable shapes. In some embodiments, such as the illustrated embodiment, the cam slots90have a shape that provides both axial and rotational movements of the inner tube82relative to the fixed outer tube80. The cam slots90may have a J-shape, with a first portion92that provides an initial slight outward axial motion combined with a rotational motion, followed a second portion94by an axial inward motion as the rotational motion continues. The initial axial outward motion (combined with a rotational motion) may provide clearance between the wing14(FIG.1) and the fuselage20(FIG.1) for the deployment. The final axial inward motion (again combined with a rotational motion) may pull the wing14close into engagement with the fuselage20, which may provide for better aerodynamics. In one embodiment the wings14and16may be lifted 0.8 cm (0.3 inches) away from the fuselage20(FIG.1) during the first 40% or wing rotation, may be drawn back in toward the fuselage20by 2.4 cm (0.95 inches) during the remaining 60% of wing rotation, and may be drawn in an additional 0.4 cm (0.15 inches) after the deploying rotation of the wings14and16. This are only example values and many variations are possible.

The terminus96of the second portion94may be principally in an axial (vertical) direction, such as by being more axial than rotational. More narrowly, the direction of the terminus96of the second portion94of the slots90may have a slope (vertical:rotational) of at least 10:1, or may be substantially axial, for example being axial to within 1%, 2%, 5%, or 10%. This puts material of the outer tube80rotationally on either side of a follower in the cam slots90. Such a configuration aids in maintaining the wing14(or other deployable device) in a deployed position, since forces tending to move the wing14in a rotational direction, such as away from the deployed position, are mostly not in the direction that the cam follower would need to take to move along the cam slots90.

Once a follower such as a lift bar (discussed below) enters the substantially axial or vertical portion96of the J-slots90, the mechanism motion of the lift bar, the inner tube82, and hence the wing14, is irreversible with respect to rotation. The lift bar could still move up/down, back-driving components such as the walking links and the slew ring (discussed below), but will not rotate any further. The width of the J-slot cam slots90for all but the last length (e.g., 2.5 mm (0.1 inch)) of the vertical portion terminus96may be considerably wider (e.g., 0.25 mm (0.01 inch) wider) than the follower (lift bar), to provide free-running clearance. At the very end of the terminus96that width is reduced, at a reduced-width portion97, so that the lift bar (follower) will fit tightly in cam slot90, assuring precise angular positioning of the wings14and16, preventing rotation of the wings14and16due to mechanism backlash. This provides a “locking” of the wings14and16in their deployed positions, allowing the wings14and16to resist angular movement from aerodynamic forces.

The inner tube82includes a through slot98to receive for a cam follower, a lift bar that is discussed below. The through slot98has a shape that corresponds to the portion of the bar that engages the through slot98. The inner tube82has an inner platform110, recessed downward from a top side of the inner tube82. The platform110has a center hole112and a pair of curved adjustment slots114that are diametrically-opposed, on opposite sides of the center hole112.

The inner tube82also has a flange or torque tang116, which is used for engaging a corresponding recess in the wing mount24(FIG.3), as described further below. The flange116also includes a receiver118that is part of a detent mechanism, also described further below.

FIG.8shows another part of the hub assembly34, a tension rod120that passes through the center hole112(FIG.7). The tension rod120holds together the parts of the hub assembly34(FIG.5) and provides a way to adjust positioning of the wing mount24(FIG.3). The tension rod120also receives a lift bar121that acts as a cam follower as it travels in the cam slots90(FIG.7), as discussed further below.

The tension rod120has a pair of threaded ends122and124on opposite ends of a center portion126. The threaded end122is for adjusting positioning of the tension rod120relative to the inner tube82. The end122is inserted into the center hole112(FIG.7), with an adjusting nut132below the platform110(FIG.7), and a lock nut134above the platform110. A tool (not shown) can be inserted through the adjustment slots114to turn the adjusting nut132to position the adjusting nut132in a desired position along the threaded end122. The lock nut134can then be tightened to clamp the platform110.

The central portion126of the tension rod120has a rectangular through-opening or window136that aligns with the through slot98(FIG.7) in the inner tube82(FIG.7), to receive a rectangular cross-section portion142of the lift bar121. The opening136may be configured to allow slight vertical shifting (a tilting) of ends of the lift rectangular bar portion142. For example a lower wall of the opening136may be slightly raised in the center, to allow pivoting of the bar portion142. This allows relief of stresses caused by any slight asymmetry in the mechanism.

A coil spring144is wrapped around the central portion126, between a widened portion146and a stop ring washer148. The coil spring144provides a spring force to assist in ejecting the tight-fitting wing mount24from the inner tube82, should the wing14ever need to be removed.

FIG.9shows motion components of the hub assembly34: a slew ring162with bearings164, a pair of walking links166and168on respective ends172and174of the lift bar121, and a pair of knuckle caps182and184. The slew ring162is mounted to a bottom end of the outer tube80, with the bearings164facilitating motion of the slew ring164about the central axis44of the hub assembly34.

The walking links166and168employ low-friction cross-joints to engage the lift bar ends172and174. An alternative configuration could utilize spherical bearings instead of the cross-joints. The walking link166includes sleeve member186and a fork187. The sleeve186receives the bar end172in a through hole, and is pivotally mounted to the fork187. The walking link168includes a sleeve188and a fork189in a similar arrangement. The sleeves186and188are axially constrained but free to pivot at the bar ends172and174.

The knuckle caps182and184retain ball ends, such as a ball end194, of the forks187and189, within corresponding sockets in the slew ring162. The forks187and189are able to pivot relative to the slew ring162using this ball-and-socket coupling.

The slew ring162has a clevis196for receiving an end of an actuator rod or tube. The clevis196is the point at which force is applied by the actuator40(FIG.3) to rotate the slew ring162.

FIGS.10and11show details of the actuator40. The actuator40is essentially a high-efficiency, powered, push/pull turnbuckle, which is reversible in operation (able to be deployed and retracted multiple times, for instance for testing). The actuator40includes a motor202, gearing204, and a pair of ballscrew drive retractor links206and208. The retractor links206and208are coupled to the slew rings, such as slew ring162, of the respective hub assemblies34and36. The motor202is used to drive both of the retractor links206and208simultaneously, with the retractor links206and208turning parts of the hub assemblies34and36to simultaneously deploy the wings14and16.

The motor202may be a standard electric motor, using electric power (such as from a battery) to turn a motor shaft212. The motor202may have a brake214coupled to it, to act as a lock to prevent movement of the retractor links206and208when the system is not in the process of deployment (when in the fully stowed or fully deployed state).

The gearing204is a compound reduction gear set (consisting of204aspur and204bpinion) that transmits rotation of the motor shaft212to both spur gears220and222, coupled together back to back. Alternatively the spur gear218may be a unitary single-piece spur gear. The spur gears220and222have respective threaded shafts226and228attached at their centers. The threaded shafts226and228are coaxial, extending away in opposite directions from the compound spur gear218. The shafts226and228are threaded in opposite directions.

The spur gears220and222may have a large number of teeth, for example each having at least 120 teeth. The large number of teeth minimizes the effect of any misalignment of the teeth between the two spur gears220and222. It will be appreciated that other numbers of teeth may be utilized. It is desirable that the spur gears220and222have a large enough diameter to permit fitment of bearings, such as bearings230and232, inside of the gears220and222, and have fine enough gear teeth (a large enough tooth count) to minimize asymmetry in the assembled actuator40.

Ballscrew nuts236and238engage the threaded shafts226and228such that the nuts236and238move along the shafts226and228as the shafts226and228are rotated. Respective link tubes242and244are attached to the nuts236and238, and move along with the nuts236and238. The link tubes242and244are hollow, allowing portions of the threaded shafts236and238to rotate freely within them. The link tubes242and244include respective guide keys246and248, which engage tracks252and254on a housing part256, to aid in guiding movement of the link tubes242and244, and to react to torques. Far ends262and264of the link tubes242and244are configured to engage clevises of the slew rings (such as the clevis196(FIG.9) of the slew ring162(FIG.9). To this end the ends262and264may have holes for receiving a suitable pins (not shown), and with the holes lined with a low-friction material, such as mounted on suitable spherical bearings, to facilitate rotation about the pins.

In operation the nuts236and238and the link tubes242and244are initially away from gearing218and220. Operation of the motor202pulls the nuts236and238and the link tubes242and244in toward the center of the actuator40.

FIGS.12and13show the assembled hub assembly34, and its coupling to the wing hub24.FIGS.14-16show further details of the connection of the wing hub24. The wing hub24has a shank284that is a tight fit with the inner tube82of the hub assembly34. The wing14is mounted to the wing hub24by a series of bolts or other fasteners on a periphery of the wing hub24. In an alternate configuration, the wing hub is integral with the wing itself.

Torque is transmitted between the inner tube82and the wing hub or mount24by the torque tang116on the inner tube82, which engages a corresponding recess294on the wing hub24.

The wing mount24is secured to the hub assembly34by use of a nut304that has an internally-threaded shaft that threads onto the tension rod threaded end124. This secures material of the wing mount24that is underneath a nut head306of the nut304. The nut304is tightened by engagement of an appropriate tool with a recess308, such as a square or other-shaped recess, in the nut head306, in this case a standard ½″ drive socket wrench extension. The nut head306has ratchet teeth312, which engage a spring-loaded and mechanically retained ratchet tube316, to keep the nut304from loosening once it is tightened. A cam-actuated nut retainer plate322is used to engage a groove324in the nut head306during removal of the nut304. This transfers forces on the nut304to the wing mount24during removal of the wing14, to help extract the wing hub shank284from an inner surface326of the inner hub82. The nut304may be loosened to allow the wing14to be rotated. The nut304may be removed entirely to allow complete removal of the wing14.

An angle limiter330is coupled to the nut304, and has an extension332that extends into and partially fills a volume334in the hub assembly34. The extension332limits travel of a pin338that protrudes out of one side of the tension rod120. The pin338can move up and down (axially) to allow the wing mount24to disengage from the torque tang116, while still keeping the nut304engaged with the tension rod threaded end124. Also the extension332limits the rotation of the wings14and16, preventing the wings14and16from colliding with each other, either in the stowed or deployed configurations.

A detent mechanism340helps maintain the wing14deployed once the deployment process is completed. The mechanism340includes a spring-loaded ball or other object342in a cavity on the slew ring162that drops down and engages a recess in the receiver118once the wing14has been rotated into a deployed condition.

FIGS.17-19illustrate operation of the hinge52, showing three steps in the deployment process. The actuator40moves relative to the frame50during the process, changing position along the hinge52as a function of position of the slew ring162. The hinge52is used to centrally position and stabilize the actuator40, rotationally grounding the actuator40to the frame50.

FIG.20-23show the system12in four steps during the deployment of the wings14and16.FIG.20shows the stowed position.FIG.21shows an initial movement in the deployment process, with the wings14and16moved axially away from the fuselage.FIG.22shows a further step in the deployment process.FIG.23shows the wings14and16fully deployed.

Many of the features are described herein with regard to one hub assembly or wing. It will be appreciated that similar features may be found in both hub assemblies, and for the extension of both of the wings. Indeed, one advantage of the system described herein is that it provides for symmetric deployment of the wings14and16. In particular, the use of the single actuator40to simultaneous deploy both of the wings14and16provides for good symmetry of operation. This may result in (for example) symmetrical aerodynamic forces as the wings14and16are in the process of deployment.

Another advantage is that the wings14and16deploy principally by slicing through the air stream around the aircraft10. This may provide less disruption of the air stream, less in the way of undesired aerodynamic forces, and/or lighter loads on the wings14and16, relative to other deployment mechanisms.

The various parts of the system12may be made using suitable materials. For example many of the components may be made from suitable metals, such as steel, titanium, or aluminum.

The system12has been described above in terms of deploying a pair of wings14and16. It will be appreciated that system12, perhaps with suitable modifications, may be used to deploy a wide variety of other devices, such as control surfaces or lift surfaces for aerial vehicles, fins or other parts of water vehicles, and/or any of a variety of objects, such as solar panels, for vehicles, such as space vehicles.