A fixed-wing unmanned aerial vehicle mounted with a cartridge-rotating injection type micro-thruster

Abstract

This invention discloses a fixed-wing unmanned aerial vehicle (UAV) equipped with a rotary injection micro-thruster, belonging to the field of UAV technology. The UAV has a mounting slot at the wingtip, with the leading edge of the airfoil in front of the slot and a closed wing surface structure on the inside, forming openings towards the trailing edge of the wing and away from the fuselage. A servo gimbal is located within the mounting slot, and the rotary injection micro-thruster and laser emission device are fixedly mounted on it, with the thrust direction adjusted by dual-axis rotation. The arc distance between the gel injection hole and the laser incident hole within the micro-thruster is equal to the center distance between adjacent gel cylinders, achieving mechanical synchronization of injection and ablation. The gel tank is fixed to the bottom of the mounting slot and connected to the gel injection hole via a flexible supply pipeline for continuous propellant supply. This invention achieves precise fine-tuning of flight attitude through multi-directional thrust vector output at the wingtip under conditions of reduced control surface efficiency, featuring a compact structure and long-term operational capability.

Description

Technical Field

[0001] This invention belongs to the field of unmanned aerial vehicle (UAV) technology, specifically relating to a fixed-wing UAV equipped with a magazine-driven rotary injection micro-thruster. Background Technology

[0002] When fixed-wing UAVs fly at low speeds, high altitudes, or high angles of attack, conventional control surfaces mounted on the trailing edge of the wing experience a sharp decline in control efficiency, or even failure, due to airflow separation, seriously threatening flight safety. Simultaneously, mechanical control surfaces have complex structures and suffer from issues such as wear of moving parts and hysteresis. To improve the redundancy and reliability of attitude control in complex environments, miniature thrusters can be installed on the UAV to control flight attitude using the direct torque they generate. However, existing miniature thrusters for attitude adjustment, such as solid-fuel thrusters or cold-gas thrusters, have drawbacks such as non-adjustable thrust, inability to be reused multiple times, and rapid propellant consumption, making it difficult to meet the long-term, high-frequency attitude fine-tuning requirements of UAVs. A search revealed existing disclosures of related UAV thruster technologies. CN115123537A discloses a thrust vector control device for the wingtip of a fixed-wing UAV, which generates thrust through a miniature jet thruster mounted on the wingtip and utilizes the lever arm amplification effect to achieve roll control. However, this scheme uses compressed gas as the working fluid, which has a limited capacity to carry a single working fluid and cannot be replenished during flight, thus limiting the ability to control attitude over extended periods.

[0003] Therefore, providing a drone attitude control device that allows for refillable working propellant, adjustable thrust, and continuous operation for extended periods has become a pressing technical problem to be solved in this field. Summary of the Invention

[0004] The technical problem to be solved by the present invention is that when existing fixed-wing UAVs fly at low speed, high altitude or high angle of attack, the conventional control surfaces suffer from reduced control efficiency or even failure due to airflow separation, while existing wingtip thruster solutions have the problem that the working propellant cannot be replenished during flight and cannot work continuously for a long time.

[0005] To address the aforementioned technical problems, this invention provides a fixed-wing unmanned aerial vehicle (UAV) equipped with a magazine-mounted rotary injection micro-thruster, comprising: a fuselage, a wing, a mounting slot, a servo gimbal, a magazine-mounted rotary injection micro-thruster, a laser emitting device, and a gel storage tank. The wingtip has a mounting slot formed by a downward indentation from the upper surface of the wingtip. The leading edge of the mounting slot is the airfoil leading edge, and the inner side of the mounting slot is a closed airfoil structure. The mounting slot has openings facing the trailing edge of the wing and away from the fuselage. The servo gimbal is disposed within the mounting slot, and the magazine-mounted rotary injection micro-thruster and the laser emitting device are jointly and fixedly mounted on the servo gimbal. The servo gimbal drives the magazine-mounted rotary injection micro-thruster and the laser emitting device to rotate as a whole along two axes to adjust the thrust vector direction. The rotary injection micro-thruster includes a gel chamber, gel tubes, an upper shell, and a laser conduit. The gel chamber contains several gel tubes evenly distributed circumferentially. The upper shell covers the gel chamber and has a gel injection port and a laser injection port. On the projection of the inner surface of the upper shell, the arc distance between the bottom outlet center of the gel injection port and the center of the laser injection port is equal to the arc distance between the centers of two adjacent gel tubes. The laser conduit is sealed to the laser injection port. The light outlet of the laser emitting device faces the inlet of the laser conduit. The gel storage tank is fixedly installed at the bottom of the mounting groove. The outlet of the gel storage tank is connected to the gel injection port via a flexible supply pipeline to continuously supply gel propellant during the operation of the rotary injection micro-thruster.

[0006] Furthermore, the closed boundary of the mounting slot is L-shaped in the top view; the mounting slot has a forward-recessed receiving cavity on the slot wall near the leading edge of the airfoil, and the receiving cavity is recessed from the front side of the mounting slot towards the leading edge of the wing.

[0007] Furthermore, the servo gimbal includes an upper mounting base, a lower mounting base, a first rotating shaft, a connecting plate, a left mounting base, a right mounting base, a second rotating shaft, a cantilever plate, and a support base. The upper mounting base is fixed to the inner top wall of the receiving cavity, and the lower mounting base is fixed to the horizontal support surface at the bottom of the mounting groove. The upper and lower mounting bases are arranged vertically at intervals. The upper end of the first rotating shaft is rotatably connected to the upper mounting base, and the lower end is rotatably connected to the lower mounting base. The axis of the first rotating shaft is arranged vertically. The connecting plate is fixedly connected to the first rotating shaft, and the left and right mounting bases are fixedly mounted on the connecting plate. The mounting bases are arranged horizontally and spaced to the left and right. The left end of the second rotating shaft is rotatably connected to the left mounting base, and the right end is rotatably connected to the right mounting base. The axis of the second rotating shaft is arranged horizontally and is orthogonal to the axis of the first rotating shaft. The cantilever plate is fixedly connected to the second rotating shaft. The bearing base is fixedly connected to the front end of the cantilever plate. The bearing base has a U-shaped structure, consisting of a bottom surface and a top surface. The bottom surface is fixedly connected to the cantilever plate. The bottom surface and the top surface extend downward and upward respectively, forming an enclosed space with openings at the front and horizontal sides. The magazine rotary injection micro-thruster and the laser emitting device are fixedly installed inside the bearing base.

[0008] Furthermore, the first rotating shaft is driven by a yaw drive motor, which is fixedly installed at the bottom of the mounting slot, and the output shaft of the yaw drive motor is connected to the first rotating shaft via a transmission connection; the second rotating shaft is driven by a pitch drive motor, which is fixedly installed on the connecting plate, and the output shaft of the pitch drive motor is connected to the second rotating shaft via a transmission connection; the rotation range of both the first and second rotating shafts is ±45 degrees.

[0009] Furthermore, the gel injection hole is a columnar channel with an inclined vertical cross-section, which runs obliquely from the outer surface of the upper shell to the inner surface.

[0010] Furthermore, the magazine-type rotary injection micro-thruster also includes a lower housing, a rotary support cylinder, a drive gear, a countersunk fastening screw, a driven gear, and a gel chamber shaft. The lower housing is flat, with the rotary support cylinder at one end and the drive gear at the other end. The rotary support cylinder is an upwardly convex hollow cylinder with a transmission window on its side wall. The teeth of the drive gear extend into the rotary support cylinder through the transmission window and mesh with the driven gear. The driven gear is located inside the rotary support cylinder and is coaxially fixed to the gel chamber shaft. The gel chamber is located inside the rotary support cylinder, and the gel chamber shaft is fixedly connected to the gel chamber. There are four gel chambers.

[0011] Furthermore, the outer wall of the rotating support cylinder is provided with a screw-locking groove, which has a wide end and a narrow end; the lower end face of the upper shell is provided with an L-shaped screw-locking claw, which first extends downward and then bends horizontally inward. The L-shaped screw-locking claw is inserted into the wide end of the screw-locking groove and rotates and slides into the narrow end to lock.

[0012] Furthermore, the lower end of the countersunk fastening screw is provided with three fixing feet, which are arranged in a triangle and are all fixedly connected to the lower housing; the upper end of the countersunk fastening screw is provided with a rotating shaft, which is rotatably connected to the drive gear through a bearing.

[0013] Furthermore, the laser guide tube is a rigid, transparent tube with a polished inner wall, and the laser transmittance is not less than 95%; the laser beam emitted by the laser emitting device and the gas ejection share the same channel formed by the laser guide tube and the laser entrance hole.

[0014] Furthermore, the length of the flexible supply pipeline is greater than the maximum straight-line distance between the gel storage tank outlet and the gel injection hole when the servo gimbal rotates to its limit position. When the servo gimbal drives the magazine rotary injection micro-thruster to rotate in a dual-axis manner, the flexible supply pipeline always maintains the connection between the gel storage tank and the gel injection hole.

[0015] Compared with the prior art, the present invention has the following advantages: (1) The L-shaped closed boundary design and cavity structure of the wingtip mounting slot enable the servo gimbal to be stably embedded and installed inside the wing. The front of the mounting slot is a complete airfoil leading edge, and the inner side is a closed airfoil structure. It forms an opening towards the trailing edge of the wing and away from the fuselage. While maintaining the aerodynamic shape and avoiding jet interference with the fuselage, it provides a multi-directional thrust vector output channel for the thruster.

[0016] (2) By designing the inclined channel of the gel injection hole and the precise projection position relationship between its bottom outlet and the laser injection hole, the mechanical structure of injection and ablation is automatically synchronized. The arc distance between the center of the bottom outlet of the gel injection hole and the center of the laser injection hole is equal to the arc distance between the centers of two adjacent gel tubes on the gel tank, which makes ablation and injection spatially separated and temporally overlapping. With the gel tank continuously supplying gel propellant through a flexible supply pipeline, the thruster can work continuously for a long time.

[0017] (3) By fixing the laser emitting device and the micro-thruster together on the carrier of the servo gimbal, the laser optical path and the thruster nozzle direction are synchronized and followed. When the yaw drive motor and the pitch drive motor drive the gimbal to rotate in a dual-axis manner, the light outlet of the laser emitting device is always facing the laser guide tube inlet of the micro-thruster, ensuring the reliability of ablation propulsion under any thrust vector direction.

[0018] (4) By using the same channel for laser emission and gas ejection and separating them in time, the thruster structure is simplified and the number of exposed channels is reduced. Laser emission is completed within a pulse width of nanosecond to millisecond, and gas is ejected in the opposite direction of laser incidence after the laser pulse ends. The two go their own way and do not interfere with each other, which is conducive to the compact layout of the thruster in the wingtip mounting slot.

[0019] (5) By using the structural design of the triangular distribution of the fixed feet at the lower end of the countersunk fastening screw and the single rotating shaft at the upper end, as well as the screw-locking cooperation of the L-shaped screw claw and the screw locking groove, and the dual mounting base fixing method of the servo gimbal, the attitude stability problem of the rotating gel structure and the thrust vector adjustment mechanism under the vibration environment of UAV flight is systematically solved.

[0020] The present invention will now be further described with reference to the accompanying drawings. Attached Figure Description

[0021] Figure 1 This is a top-view structural diagram of the wing of a fixed-wing UAV.

[0022] Figure 2 This is a schematic diagram of the 3D structure of the servo gimbal.

[0023] Figure 3 A side view of the structure of the servo gimbal equipped with a rotary injection micro-thruster.

[0024] Figure 4 This is a cross-sectional schematic diagram of a magazine-driven rotary injection micro-thruster.

[0025] Figure 5 This is a schematic diagram of the lower casing of a rotary injection micro-thruster.

[0026] Figure 6 This is a schematic diagram of the gel chamber structure of a rotary injection micro-thruster.

[0027] Figure 7 This is a schematic diagram of the upper casing of a rotary injection micro-thruster.

[0028] In the diagram: lower housing 100, rotating support cylinder 110, transmission window 111, rotary locking groove 112, driving gear 200, countersunk fastening screw 210, driven gear 220, gel chamber 300, gel chamber shaft 310, gel cylinder 320, upper housing 400, gel injection hole 410, laser injection hole 420, L-shaped rotary locking claw 430, laser conduit 500, upper mounting base 610, lower mounting base 620, first rotating shaft 630, connecting plate 640, left mounting base 650, right mounting base 660, second rotating shaft 670, cantilever plate 680, bearing seat 690. Detailed Implementation

[0029] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0030] This invention provides a fixed-wing unmanned aerial vehicle (UAV) equipped with a rotary injection micro-thruster in a magazine. This micro-thruster, mounted on the wingtip, generates a direct control torque to achieve precise fine-tuning of flight attitude under conditions where control surface efficiency decreases, such as at low speeds, high altitudes, or high angles of attack.

[0031] UAV wingtip structure; reference Figure 1 The drone's wingtip features a mounting slot, which is formed by a downward indentation from the upper surface of the wingtip. The shaded area in the diagram indicates the location of the mounting slot. The area in front of the mounting slot is a complete airfoil leading edge, and the inner side of the slot is a complete closed airfoil structure. The mounting slot forms openings towards the trailing edge of the wing and away from the fuselage, and its closed boundary is L-shaped when viewed from above.

[0032] The bottom of the mounting slot is a horizontal bearing surface. On the side of the mounting slot near the airfoil leading edge, there is also a forward-recessed receiving cavity. This cavity is recessed from the front wall of the mounting slot towards the airfoil leading edge and is located within the wing's internal space between the airfoil leading edge skin and the mounting slot. The inner top wall of the receiving cavity is used to fix the upper mounting seat 610. Thus, the upper mounting seat 610 is fixed to the inner top wall of the receiving cavity, and the lower mounting seat 620 is fixed to the horizontal bearing surface at the bottom of the mounting slot. The upper mounting seat 610 and the lower mounting seat 620 are arranged vertically at intervals, and the space between them is used to accommodate the first rotating shaft 630.

[0033] The considerations for adopting the aforementioned wingtip mounting slot structure are as follows: The mounting slot is recessed downwards from the upper surface of the wingtip, ensuring that the thruster and servo gimbal do not protrude from the airfoil profile after embedding, thus reducing the impact on cruise aerodynamic drag. The receiving cavity is recessed from the front wall of the mounting slot towards the leading edge of the airfoil, housing the upper mounting seat 610 inside the wing. This ensures the vertical mounting span of the first rotating shaft 630 while preventing the upper mounting seat 610 from protruding from the mounting slot and occupying the thruster's movement space. The rear opening of the mounting slot is used for the thruster to spray rearwards, generating roll and yaw moments around the UAV's center of gravity after being amplified by the wingtip lever arm. The outer opening of the mounting slot is used for the thruster to spray outwards, generating yaw and pitch moments along the wingspan. The inner side of the mounting slot is a closed wing surface, separating the thruster jet from the fuselage and preventing high-temperature, high-speed exhaust gases from causing thermal shock to the wing skin and onboard equipment.

[0034] Servo gimbal structure; Reference Figure 2 and Figure 3 The servo gimbal is used to drive the thruster to rotate on two axes, thereby adjusting the direction of the thrust vector. The servo gimbal includes an upper mounting base 610, a lower mounting base 620, a first rotating shaft 630, a connecting plate 640, a left mounting base 650, a right mounting base 660, a second rotating shaft 670, a cantilever plate 680, and a support base 690.

[0035] A lower mounting base 620 is fixedly installed at the bottom of the mounting slot, and an upper mounting base 610 is fixedly installed on the inner top wall of the receiving cavity. The upper mounting base 610 and the lower mounting base 620 are arranged vertically at intervals. The upper end of the first rotating shaft 630 is rotatably connected to the upper mounting base 610, and the lower end is rotatably connected to the lower mounting base 620. The axis of the first rotating shaft 630 is arranged vertically. The first rotating shaft 630 is driven by a yaw drive motor, which is fixedly installed at the bottom of the mounting slot. The output shaft of the yaw drive motor is connected to the first rotating shaft 630 for transmission. When the yaw drive motor is working, the first rotating shaft 630 drives the connecting plate 640 on it to rotate around the vertical axis, realizing yaw motion in the horizontal direction.

[0036] A connecting plate 640 is fixedly connected to the first rotating shaft 630. The connecting plate 640 is flat and rotates around the vertical axis together with the first rotating shaft 630. A left mounting base 650 and a right mounting base 660 are fixedly mounted on the connecting plate 640, and the left and right mounting bases 650 and 660 are arranged horizontally at intervals. The left end of the second rotating shaft 670 is rotatably connected to the left mounting base 650, and the right end is rotatably connected to the right mounting base 660. The axis of the second rotating shaft 670 is arranged horizontally and is orthogonal to the axis of the first rotating shaft 630. The second rotating shaft 670 is driven by a pitch drive motor, which is fixedly mounted on the connecting plate 640. The output shaft of the pitch drive motor is connected to the second rotating shaft 670 for transmission. When the pitch drive motor is working, the second rotating shaft 670 drives the cantilever plate 680 and the bearing seat 690 to rotate as a whole around the horizontal axis, realizing the vertical pitch movement.

[0037] A cantilever plate 680 is fixedly connected to the second rotating shaft 670. The cantilever plate 680 extends forward and rotates around the horizontal axis together with the second rotating shaft 670. A bearing seat 690 is fixedly connected to the front end of the cantilever plate 680. The bearing seat 690 has a U-shaped structure, consisting of a bottom surface and a top surface. The bottom surface is fixedly connected to the cantilever plate 680, and the bottom surface and top surface extend downward and upward respectively, forming an enclosed space with openings at the front and horizontal sides.

[0038] The laser emitter and thruster are installed together within the carrier 690; the magazine-mounted rotary injection micro-thruster and the laser emitter are fixedly mounted. The laser emitter is fixedly mounted within the carrier 690 on one side corresponding to the laser guide tube inlet of the magazine-mounted rotary injection micro-thruster, with the laser emitter's exit port facing the laser guide tube inlet, and the relative position between the two remains constant. The laser beam emitted by the laser emitter enters through the laser guide tube inlet, propagates along the laser guide tube to the surface of the gel propellant, and the gel is ablated by the laser to generate high-temperature, high-pressure gas. The gas is ejected through the same channel in the opposite direction of the laser incident, generating thrust. The laser emitter is electrically connected to the UAV flight control system via a signal line. The flight control system controls the activation, deactivation, and emission power of the laser emitter according to attitude control commands.

[0039] When the yaw drive motor drives the first rotating shaft 630 to rotate, the connecting plate 640, the second rotating shaft 670, the cantilever plate 680, the support base 690, and the laser emitting device and micro-thruster installed in the support base 690 rotate as a whole around the vertical axis, changing the direction of thrust injection in the horizontal plane. When the pitch drive motor drives the second rotating shaft 670 to rotate, the cantilever plate 680, the support base 690, and the laser emitting device and micro-thruster installed in the support base 690 rotate as a whole around the horizontal axis, changing the direction of thrust injection in the vertical plane.

[0040] A gel supply system is included. A gel storage tank is fixedly installed on the horizontal bearing surface at the bottom of the mounting groove. The gel storage tank is located to the side of the lower mounting base 620, utilizing the remaining space at the bottom of the mounting groove. The gel storage tank is a sealed container that stores gel propellant. The outlet of the gel storage tank is connected to the gel injection port 410 of the rotary injection micro-thruster via a flexible supply pipeline. The flexible supply pipeline is a high-temperature resistant and corrosion-resistant flexible hose, and its layout path is as follows: it extends upward from the outlet of the gel storage tank, bypasses the side of the connecting plate 640, enters the bearing base 690, and finally connects to the gel injection port 410 on the upper housing 400 of the micro-thruster. The flexible supply pipeline has a reserved length within the mounting groove.

[0041] When the yaw drive motor drives the first shaft 630 to rotate, the reserved section of the flexible supply pipeline on the side of the connecting plate 640 bends accordingly to absorb displacement in the yaw direction. When the pitch drive motor drives the second shaft 670 to rotate, the reserved section of the flexible supply pipeline at the inlet of the bearing seat 690 bends accordingly to absorb displacement in the pitch direction. Through the above-mentioned dual-axis rotation and the following action of the flexible supply pipeline, under any thrust vector direction, the light outlet of the laser emitting device is always directly opposite the laser guide inlet of the micro-thruster, and the gel tank is always connected to the gel injection hole 410. Laser emission and gel supply are not affected by the rotation of the gimbal, ensuring that gel propellant can be added into the gel cylinder 320 under any thrust vector direction.

[0042] Micro-thruster structure; the magazine-driven rotary injection micro-thruster adopts a magazine-driven rotary injection laser ablation propulsion scheme. (Refer to...) Figures 4 to 7 The micro-thruster includes a lower housing 100, a rotating support cylinder 110, a driving gear 200, a countersunk fastening screw 210, a driven gear 220, a gel chamber 300, a gel chamber shaft 310, a gel cylinder 320, an upper housing 400, and a laser conduit 500.

[0043] The lower housing 100 is flat and serves as the mounting base for the entire thruster. A rotating support cylinder 110 is located at one end of the lower housing 100, and a driving gear 200 is located at the other end. The rotating support cylinder 110 is an upwardly convex hollow cylinder that houses a driven gear 220. A transmission window 111 is provided on the side wall of the rotating support cylinder 110, through which the teeth of the driving gear 200 extend into the rotating support cylinder 110 and mesh with the driven gear 220. A rotary locking groove 112 is provided on the outer wall of the rotating support cylinder 110, having a wide end and a narrow end.

[0044] The drive gear 200 is driven by a miniature servo motor, which is electrically connected to the UAV flight control system via a signal line. The countersunk screw 210 is a single component with three triangularly distributed fixing feet at its lower end, all of which are fixedly connected to the lower housing 100, forming a stable triangular support structure that effectively prevents displacement or tilting of the transmission components due to UAV flight vibrations. The upper end of the countersunk screw 210 has a rotating shaft, which is rotatably connected to the drive gear 200 via a bearing, allowing the drive gear 200 to rotate freely relative to the lower housing 100 around the shaft.

[0045] Driven gear 220 is located inside the rotating support cylinder 110 and meshes with driving gear 200 through transmission window 111. Driving gear 200 and driven gear 220 are a precision-meshing gear pair, with a coaxiality error of no more than 0.05 mm, ensuring smoothness and accuracy of the transmission process. Driven gear 220 is coaxially fixed to gel chamber shaft 310. When driven gear 220 rotates, it drives gel chamber shaft 310 to rotate together, thereby driving gel chamber 300 to rotate uniformly around the axis of rotating support cylinder 110.

[0046] The gel chamber 300 is housed within the rotating support cylinder 110 and can rotate freely around the axis of the rotating support cylinder 110. The gel chamber 300 is similar to the magazine structure of a revolver, containing four gel cartridges 320 evenly distributed circumferentially. Each gel cartridge 320 is an independent gel cavity used to contain the gel propellant. The inner wall of the gel cartridge 320's cavity is treated with an anti-stick coating to prevent residue from adhering after the gel propellant ablates, ensuring the reusability of the gel cartridge 320.

[0047] The upper housing 400 is fastened to the lower housing 100, and the upper housing 400 and the lower housing 100 are sealed together to form a closed cavity. A sealing ring is embedded in the mating surface of the lower housing 100 and the upper housing 400. The lower end face of the upper housing 400 is provided with multiple L-shaped rotary latches 430, which extend downwards and then bend horizontally inwards. During assembly, the L-shaped rotary latches 430 are aligned with the wide end of the rotary locking groove 112 and inserted. Rotating the upper housing 400 causes the horizontal extension of the L-shaped rotary latches 430 to slide along the rotary locking groove 112 from the wide end to the narrow end, thus achieving a locking connection between the upper housing 400 and the rotating support cylinder 110.

[0048] The upper housing 400 has a gel injection hole 410 and a laser injection hole 420. The gel injection hole 410 is a columnar channel with an inclined cross-section, extending obliquely from the outer surface to the inner surface of the upper housing 400. Projected onto the inner surface of the upper housing 400, the arc distance between the center of the bottom outlet of the gel injection hole 410 and the center of the laser injection hole 420 is equal to the arc distance between the centers of two adjacent gel cylinders 320 on the gel chamber 300. Therefore, when any gel cylinder 320 rotates to align with the laser injection hole 420 for ablation propulsion, its adjacent gel cylinder 320 rotates precisely to align with the bottom outlet of the gel injection hole 410 for gel filling. The filling process and the ablation propulsion process are spatially separated but temporally overlapped, enabling continuous operation of filling and ablation simultaneously. The inclined channel of the gel injection hole 410 guides the gel to be injected into the gel cylinder 320 at an oblique angle, ensuring smooth filling of the cavity and avoiding air bubbles or uneven filling that occurs during vertical injection.

[0049] The laser entrance aperture 420 is sealed to the laser conduit 500. The laser conduit 500 is a rigid, transparent tube with a polished inner wall, ensuring a laser transmittance of no less than 95% to guarantee efficient laser energy transmission to the surface of the gel propellant. A sealing gasket is provided at the connection between the laser conduit 500 and the upper housing 400 to prevent gas from escaping from the laser entrance aperture 420. The laser beam emitted by the laser emitting device passes through the laser conduit 500 and the laser entrance aperture 420, directly irradiating the surface of the gel propellant inside the gel cylinder 320. After the gel is ablated by the laser, high-temperature, high-pressure gas is generated. The gas is ejected along the opposite direction of the laser incident direction through the same channel, generating thrust. The laser emission and gas ejection share the same channel, each proceeding independently without interference.

[0050] All components of this thruster are manufactured using 3D printing, forming a single integrated unit. The 3D printing process employs photosensitive resin or metal powder sintering technology, ensuring that the surface roughness Ra of each printed component does not exceed 3.2 micrometers. The mating surfaces undergo secondary finishing treatment to guarantee the assembly accuracy and smooth transmission of each component.

[0051] Work process During UAV flight, when attitude adjustments are needed, the flight control system sends commands to the micro-thrusters and servo gimbal based on attitude deviations detected by the gyroscope. The yaw and pitch drive motors of the servo gimbal drive the first shaft 630 and the second shaft 670 to rotate, respectively, adjusting the micro-thruster nozzles within the support 690 to the desired direction. When the nozzles face the opening of the mounting slot towards the wing's trailing edge, the thrust is amplified by the wingtip lever arm, generating a roll torque around the UAV's center of gravity, with the differential operation of the two wingtip micro-thrusters controlling the roll. When the nozzles face the opening of the mounting slot away from the fuselage, the thrust is ejected outwards along the wingspan, generating a yaw torque. Through the differential operation of the two wingtip micro-thrusters and the vector control of the servo gimbal, precise fine-tuning of the UAV's pitch, yaw, and roll is achieved.

[0052] When attitude adjustment needs to be stopped, the flight control system shuts off the laser source, and the thruster immediately stops working. By adjusting the laser energy and spot size, the gel ablation rate can be changed, thereby controlling the thrust impulse. When the gel in a gel canister 320 is depleted, the flight control system controls the gel chamber 300 to rotate, switching the next gel-filled gel canister 320 to the laser entrance port 420. At the same time, the depleted gel canister 320 rotates to the gel injection port 410, and the gel propellant in the gel tank is injected into the empty canister through the flexible supply pipeline and the gel injection port 410 for replenishment. Thus, this thruster can operate continuously for extended periods, meeting the UAV's need to continuously provide attitude control torque in emergency situations such as control surface failure.

[0053] Theoretical derivation of application effects The following quantitative analysis of the attitude control effect of this thruster on UAVs of different mass levels is based on specific aircraft parameters. In the theoretical calculation, the thrust F of a single pulse is taken as 0.1 N, the duration t of a single pulse is taken as 10 milliseconds (0.01 seconds), and the impulse is F multiplied by t, which equals 0.001 N / s. For ease of calculation, the following analysis takes the cumulative impulse of 10 consecutive pulses as 0.01 N / s.

[0054] Scene 1: Small fixed-wing aircraft, weighing 5 kg and with a wingspan of 2 meters.

[0055] Analysis of the translational effect: The cumulative impulse of 10 consecutive pulses is 0.01 N / s. The velocity increment ΔV is derived from the momentum theorem, where ΔV equals the cumulative impulse divided by the aircraft mass, i.e., 0.01 divided by 5, resulting in 0.002 m / s. The thrust within a single pulse duration of 10 milliseconds is 0.1 N, and the instantaneous acceleration a equals the thrust divided by the mass, i.e., 0.1 divided by 5, resulting in 0.02 m / s². The displacement increment is extremely small. For translational motion, due to the large mass of the aircraft, the translational velocity increment generated by a single pulse is limited. The direct impact of this thruster on the UAV's orbital motion is small; its main function is attitude adjustment.

[0056] Attitude effect analysis: The thrust is mounted at the wingtip, with a lever arm L of 1 meter. The moment of inertia I of the aircraft about its roll axis is approximately 0.5 kg / m². The impulse moment of a single pulse equals the thrust F multiplied by the lever arm L multiplied by the pulse time t, i.e., 0.1 multiplied by 1 multiplied by 0.01, resulting in 0.001 Nm / s. The angular velocity increment Δω equals the impulse moment divided by the moment of inertia I, i.e., 0.001 divided by 0.5, resulting in 0.002 radians per second. The cumulative angular velocity increment of 10 consecutive pulses is 0.02 radians per second. By the law of conservation of energy, rotational kinetic energy equals half multiplied by the moment of inertia I multiplied by the square of the angular velocity. Angular displacement Δθ equals rotational kinetic energy divided by the damping torque coefficient. Under ideal, undamped conditions, angular displacement Δθ equals the square of the cumulative impulse moment divided by 2 multiplied by the moment of inertia I, i.e., the square of 0.1 multiplied by 1 multiplied by 0.01 multiplied by 10 divided by 2 multiplied by 0.5, resulting in 0.01 radians, approximately 0.57 degrees. Considering the effect of aerodynamic damping in actual flight, the aerodynamic damping torque coefficient increases with increasing flight speed. At a cruise speed of 10 to 20 meters per second, the actual usable attitude angle range is approximately 5 to 30 degrees, with the specific value depending on real-time conditions such as flight speed, angle of attack, and atmospheric density. This level of attitude adjustment capability is sufficient to meet the large-angle attitude correction requirements of small fixed-wing aircraft at medium speeds, effectively addressing adverse conditions such as gusts and reduced control surface efficiency.

[0057] Scenario 2: A heavy aircraft, weighing 50 kg and with a wingspan of 4 meters.

[0058] Translational effect analysis: The cumulative impulse of 10 consecutive pulses is 0.01 N / s. The velocity increment ΔV is equal to the cumulative impulse divided by the mass of the aircraft, i.e., 0.01 divided by 50, which results in 0.0002 m / s. For a 50 kg class aircraft, the translational motion is almost imperceptible, and the trajectory control effect of this thruster on such aircraft is negligible.

[0059] Attitude Effect Analysis: The thrust is mounted at the wingtip, with a lever arm L of 2 meters. The moment of inertia I of the aircraft about its roll axis is approximately 20 kg / m². The impulse moment of a single pulse equals the thrust F multiplied by the lever arm L multiplied by the pulse time t, i.e., 0.1 multiplied by 2 multiplied by 0.01, resulting in 0.002 Nm / s. The angular velocity increment Δω equals the impulse moment divided by the moment of inertia I, i.e., 0.002 divided by 20, resulting in 0.0001 radians per second. The cumulative angular velocity increment of 10 consecutive pulses is 0.001 radians per second. Under ideal, undamped conditions, the angular displacement Δθ equals the square of the cumulative impulse moment divided by 2 multiplied by the moment of inertia I, i.e., the square of 0.1 multiplied by 2 multiplied by 0.01 multiplied by 10 divided by 2 multiplied by 20, resulting in 0.001 radians, approximately 0.057 degrees. Considering the effect of aerodynamic damping in actual flight, at a cruise speed of 15 to 25 meters per second, the actual usable attitude angle range is approximately 2 to 10 degrees. For a 50-kilogram aircraft, an attitude correction range of 2 to 10 degrees is sufficient to meet the needs of fine-tuning the attitude. Small-angle corrections to the yaw and pitch channels can be completed without activating conventional control surfaces, reducing mechanical wear on the control surfaces and improving the redundancy and reliability of the flight control system.

[0060] The analysis of the two scenarios above shows that this thruster can generate effective attitude control torque on fixed-wing UAVs of different mass levels. Small fixed-wing aircraft can achieve large-angle maneuvers by utilizing the wingtip lever arm amplification effect, while heavy aircraft can use this thruster for fine-tuning of attitude. The translational motion of both types of aircraft is minimally affected by the thrust; the thruster's role is mainly concentrated in the attitude control channel. This is highly consistent with the design goal of this invention, which is to provide auxiliary attitude control torque when control surface efficiency decreases.

[0061] Example 1 uses a small fixed-wing UAV with a wingspan of 2 meters and a weight of 5 kilograms as the application object. A rotary injection micro-thruster with a magazine is installed on each of the two wingtips. Four gel cylinders 320 are used in the micro-thruster. The gel propellant, made of energetic gel material, is stored in a gel tank at the bottom of the mounting slot and supplied to the gel injection port 410 via a flexible supply pipeline. The rotation range of the first and second rotating shafts 630 and 670 of the servo gimbal is ±45 degrees. The laser emitting device uses a semiconductor laser with a peak power of 10 watts and a pulse width of 10 milliseconds. When the UAV encounters crosswind disturbances during cruise, the flight control system sends a command to the right wingtip micro-thruster based on the roll attitude deviation sensed by the gyroscope. The right wingtip micro-thruster emits laser pulses at a frequency of 10 Hz. Each pulse ablates the gel, generating 0.1 Newtons of thrust, which lasts for 0.1 seconds. After being amplified by a 1-meter lever arm, it generates a roll torque, allowing the UAV to complete roll attitude correction within 0.5 seconds. After the correction is completed, the flight control system shuts down the laser source, and the thruster stops working. During the entire correction process, the thruster consumes approximately 0.01 grams of gel, and a single gel cartridge 320 can support thousands of pulse ablation cycles. When the gel in the gel cartridge 320 is depleted, the gel tank 300 automatically rotates to switch to the next gel cartridge 320 that has been filled with gel. Simultaneously, the empty cartridge rotates to the gel injection port 410, and the gel storage tank is replenished via a flexible supply pipeline, achieving uninterrupted continuous operation.

[0062] Example 2 uses a medium-sized fixed-wing UAV with a wingspan of 4 meters and a mass of 50 kg as the application object. A micro-thruster with a magazine-style rotary injection is installed on each wingtip. The micro-thruster has six gel cartridges 320. The gel propellant, made of energetic gel material, is stored in a gel tank at the bottom of the mounting slot and supplied to the gel injection port 410 via a flexible supply pipeline. The six gel cartridges 320 provide a larger working propellant reserve and a longer continuous operating time. The rotation range of the first axis 630 and the second axis 670 of the servo gimbal is ±45 degrees. The laser emitting device uses a fiber laser with a peak power of 50 watts and a pulse width of 5 milliseconds. During high-altitude cruise, the reduced atmospheric density causes a decrease in the efficiency of the aileron control surfaces. Based on the roll attitude deviation sensed by the gyroscope, the flight control system activates the wingtip micro-thrusters for auxiliary attitude correction. The wingtip micro-thrusters emit differential laser pulses at a frequency of 20 Hz. Each pulse ablates the gel, generating 0.2 Newtons of thrust. After being amplified by a 2-meter lever arm, this thrust produces a roll torque, allowing the UAV to complete roll attitude correction within 1 second. The maximum roll angular velocity during the correction is 5 degrees per second, and the attitude adjustment process is smooth. After the correction is complete, the flight control system shuts off the laser source, and the thrusters cease operation. The thrusters consume approximately 0.02 grams of gel during the entire correction process, and a single gel cartridge 320 can support thousands of pulse ablations. When the gel in the gel cartridge 320 is depleted, the gel tank 300 automatically rotates to switch to the next gel-filled gel cartridge 320. Simultaneously, the empty cartridge rotates to the gel injection port 410, and the gel storage tank is replenished via a flexible supply pipeline, enabling uninterrupted continuous operation.

[0063] The above are merely preferred embodiments of the present invention and do not limit the scope of the patent. Any equivalent structural modifications made based on the concept of the present invention and the content of this specification, or any direct or indirect applications in other related technical fields, are included within the scope of patent protection of the present invention.

Claims

1. A fixed-wing unmanned aerial vehicle equipped with a magazine-driven rotary injection micro-thruster, characterized in that, include: The fuselage, wings, mounting slots, servo gimbal, rotary injection micro-thruster for the bomb bay, laser emitting device, and gel storage tank, among which, The wingtip has a mounting slot, which is formed by a downward indentation from the upper surface of the wingtip. The front of the mounting slot is the airfoil leading edge, the inner side of the mounting slot is a closed airfoil structure, and the mounting slot forms an opening in the direction towards the trailing edge of the wing and away from the fuselage. The servo gimbal is set in the mounting slot, and the magazine rotary injection micro-thruster and laser emission device are fixedly mounted on the servo gimbal. The magazine-type rotary injection micro-thruster includes a gel chamber (300), a gel cylinder (320), an upper shell (400), and a laser guide (500); among which, The gel chamber (300) is provided with several gel tubes (320), which are evenly distributed in a circle. The upper shell (400) is placed on top of the gel chamber (300). The upper shell (400) is provided with a gel injection hole (410) and a laser injection hole (420). On the projection of the inner surface of the upper shell (400), the arc distance between the bottom outlet center of the gel injection hole (410) and the center of the laser injection hole (420) is equal to the arc distance between the centers of two adjacent gel tubes (320). The laser conduit (500) is sealed and connected to the laser injection hole (420). The light outlet of the laser emitting device is directly opposite the inlet of the laser guide tube (500); The gel storage tank is fixedly installed at the bottom of the installation groove, and the outlet of the gel storage tank is connected to the gel injection hole (410) through a flexible supply pipeline.

2. A fixed-wing unmanned aerial vehicle equipped with a magazine-driven rotary injection micro-thruster according to claim 1, characterized in that, The closed boundary of the mounting slot is L-shaped in the top view; the mounting slot has a forward-recessed receiving cavity on the slot wall near the leading edge of the airfoil, and the receiving cavity is recessed from the front side of the mounting slot towards the leading edge of the airfoil.

3. A fixed-wing unmanned aerial vehicle equipped with a magazine-driven rotary injection micro-thruster according to claim 1, characterized in that, The servo gimbal includes an upper mounting base (610), a lower mounting base (620), a first rotating axis (630), a connecting plate (640), a left mounting base (650), a right mounting base (660), a second rotating axis (670), a cantilever plate (680), and a support base (690); among which, The upper mounting base (610) is fixed to the inner top wall of the receiving cavity, and the lower mounting base (620) is fixed to the horizontal bearing surface at the bottom of the mounting groove. The upper mounting base (610) and the lower mounting base (620) are arranged vertically at intervals. The upper end of the first rotating shaft (630) is rotatably connected to the upper mounting base (610), and the lower end is rotatably connected to the lower mounting base (620). The axis of the first rotating shaft (630) is arranged in the vertical direction. The connecting plate (640) is fixedly connected to the first rotating shaft (630). A left mounting seat (650) and a right mounting seat (660) are fixedly provided on the connecting plate (640). The left mounting seat (650) and the right mounting seat (660) are arranged at intervals on the left and right sides in the horizontal direction. The left end of the second rotating shaft (670) is rotatably connected to the left mounting base (650), and the right end is rotatably connected to the right mounting base (660). The axis of the second rotating shaft (670) is arranged in the horizontal direction and is orthogonal to the axis of the first rotating shaft (630). The cantilever plate (680) is fixedly connected to the second rotating shaft (670); The support seat (690) is fixedly connected to the front end of the cantilever plate (680). The support seat (690) has a U-shaped structure and consists of a bottom surface and a top surface. The bottom surface is fixedly connected to the cantilever plate (680). The bottom surface and the top surface extend downward and upward respectively to form an enclosed space with an open front and horizontal sides. The magazine-mounted rotary injection micro-thruster and the laser emitting device are fixedly installed in the support base (690).

4. A fixed-wing unmanned aerial vehicle equipped with a magazine-driven rotary injection micro-thruster according to claim 3, characterized in that, The first rotating shaft (630) is driven by a yaw drive motor, which is fixedly installed at the bottom of the mounting slot. The output shaft of the yaw drive motor is connected to the first rotating shaft (630) in a transmission connection. The second rotating shaft (670) is driven by a pitch drive motor, which is fixedly mounted on the connecting plate (640). The output shaft of the pitch drive motor is connected to the second rotating shaft (670) in a transmission connection. The rotation range of both the first rotating shaft (630) and the second rotating shaft (670) is ±45 degrees.

5. A fixed-wing unmanned aerial vehicle equipped with a magazine-driven rotary injection micro-thruster according to claim 1, characterized in that, The gel injection hole (410) is a columnar channel with an inclined vertical cross section, which extends obliquely from the outer surface of the upper shell (400) to the inner surface.

6. A fixed-wing unmanned aerial vehicle equipped with a magazine-driven rotary injection micro-thruster according to claim 1, characterized in that, The magazine-mounted rotary injection micro-thruster also includes a lower housing (100), a rotary support cylinder (110), a drive gear (200), a countersunk fastening screw (210), a driven gear (220), and a gel chamber shaft (310); among which, The lower housing (100) is flat, with a rotating support cylinder (110) at one end and a drive gear (200) at the other end. The rotating support cylinder (110) is a hollow cylinder that bulges upward, and a transmission window (111) is provided on the side wall of the rotating support cylinder (110). The teeth of the driving gear (200) extend into the rotating support cylinder (110) through the transmission window (111) and mesh with the driven gear (220); The driven gear (220) is located inside the rotating support cylinder (110) and is coaxially fixed to the gel chamber shaft (310); The gel chamber (300) is disposed inside the rotating support cylinder (110), and the gel chamber shaft (310) is fixedly connected to the gel chamber (300); The number of gel tubes (320) is four.

7. A fixed-wing unmanned aerial vehicle equipped with a magazine-driven rotary injection micro-thruster according to claim 6, characterized in that, The outer wall of the rotating support cylinder (110) is provided with a swivel locking groove (112). The rotary locking groove (112) has a wide end and a narrow end; The lower end face of the upper housing (400) is provided with an L-shaped swivel claw (430). The L-shaped swivel claw (430) extends downward and then bends horizontally inward. The L-shaped swivel claw (430) is inserted into the wide end of the swivel locking groove (112) and rotated into the narrow end to lock.

8. A fixed-wing unmanned aerial vehicle equipped with a magazine-driven rotary injection micro-thruster according to claim 6, characterized in that, The countersunk fastening screw (210) has three fixing feet at its lower end. The three fixing feet are arranged in a triangle and are fixedly connected to the lower housing (100). The upper end of the countersunk fastening screw (210) is provided with a pivot, which is rotatably connected to the drive gear (200) via a bearing.

9. A fixed-wing unmanned aerial vehicle equipped with a magazine-driven rotary injection micro-thruster according to claim 1, characterized in that, The laser guide tube (500) is a rigid, transparent tube with a polished inner wall and a laser transmittance of not less than 95%. The laser beam emitted by the laser emitting device shares the same channel formed by the laser guide tube (500) and the laser entrance hole (420) with the gas ejection.

10. A fixed-wing unmanned aerial vehicle equipped with a magazine-driven rotary injection micro-thruster according to claim 1, characterized in that, The length of the flexible supply pipeline is greater than the maximum straight distance between the gel storage tank outlet and the gel injection hole (410) when the servo gimbal rotates to the limit position. When the servo gimbal drives the magazine rotary injection micro thruster to rotate in a dual-axis manner, the flexible supply pipeline always maintains the connection between the gel storage tank and the gel injection hole (410).

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