A rotor type unmanned aerial vehicle installed with a laser oblique scanning type micro-thruster

Abstract

The application discloses a rotor unmanned aerial vehicle provided with laser oblique scanning type micro thrusters and belongs to the technical field of unmanned aerial vehicles. The unmanned aerial vehicle is provided with two installation grooves on the two sides of the tail of the body, the axis of the two installation grooves forms a 90-degree included angle in the horizontal plane, and one laser oblique scanning type micro thruster is fixedly installed in each installation groove. The thruster comprises a shell, a cover plate, a Laval nozzle, a laser source, a motor, a pushing rod and a fixing rod, a gel propellant is filled in the shell, one end of the shell close to the Laval nozzle is provided with an inclined surface, the laser source is fixedly arranged outside the cover plate, a laser beam is emitted to irradiate the inclined surface of the gel propellant at an oblique angle to realize ignition, and the feeding speed of the motor is coupled with the laser ablation speed. The flight control system controls the opening, closing and thrust size of the two thrusters respectively, and the yaw moment is generated through the thrust vector synthesis. The application provides fine attitude fine adjustment of the yaw channel on the basis of the rotor system, has fast response and simple structure, and does not need a servo holder.

Description

Technical Field

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

[0002] In complex airflow environments, high-maneuver flight, or rotor failure conditions, rotor-based unmanned aerial vehicles (UAVs) relying solely on differential rotor speeds for attitude control suffer from response lag and insufficient control torque, seriously threatening flight safety. To improve the redundancy and reliability of attitude control in extreme conditions, miniature thrusters can be installed on the airframe, utilizing the direct torque generated by the thrusters for auxiliary attitude control. In the field of laser micro-propulsion technology, laser micro-thrusters generate thrust based on the principle of laser ablation, offering advantages such as non-contact operation, high precision, and finely adjustable thrust. Existing laser micro-thrusters mainly employ two operating modes: transmission-type and side-scanning-type. Transmission-type ablation requires the laser to penetrate the working fluid from the back of a transparent substrate, resulting in a complex structure. Furthermore, the laser energy must penetrate the substrate before acting on the working fluid, and the energy deposition efficiency is limited by the substrate transmittance and the working fluid absorption coefficient. In side-scanning ablation, the laser source needs to move to scan the working fluid surface. The laser source's movement speed is difficult to precisely match with the working fluid's combustion speed, leading to unstable thrust, and combustion products are easily sputtered onto the optical window, causing contamination. Furthermore, existing rotary-wing UAVs, when equipped with thrusters, typically only achieve thrust output in a single direction, and cannot achieve multi-channel attitude control (pitch, yaw, and roll) through the coordinated operation of multiple thrusters. If multiple thrusters are fixedly installed, how to achieve multi-channel attitude control through reasonable layout and thrust distribution is a key problem that needs to be solved in this field.

[0003] Therefore, providing a rotary-wing UAV attitude control device with a simple and compact structure, which can achieve multi-channel attitude control through a fixed layout of multiple thrusters and has precisely adjustable thrust has become a technical problem that urgently needs to be solved in this field. Summary of the Invention

[0004] The technical problem to be solved by this invention is that existing rotary-wing UAVs, when operating in complex airflow environments, hovering or high-maneuver flight conditions, rely solely on differential rotor speed to achieve yaw attitude control, which suffers from response lag and insufficient accuracy. Existing laser micro-thrusters mostly adopt transmission or side-scanning working modes, which have defects such as complex structure, difficulty in speed coupling, and easy contamination of optical windows. Moreover, they usually need to be used in conjunction with servo gimbals to achieve multi-directional thrust vector output, which increases the system weight and structural complexity.

[0005] To address the aforementioned technical problems, this invention provides a rotary-wing unmanned aerial vehicle (UAV) equipped with a laser oblique scanning micro-thruster, comprising: a fuselage, a first thruster, a second thruster, and a flight control system. The fuselage has a mounting slot on each side of its tail, with the axes of the two mounting slots forming a 90° angle in the horizontal plane. Both the first and second thrusters are laser oblique scanning micro-thrusters, fixedly installed in the two mounting slots. The nozzle of the first thruster faces one side of the tail of the fuselage, and the nozzle of the second thruster faces the other side of the tail of the fuselage. The thrust vectors of the two nozzles are perpendicular to each other in the horizontal plane. The laser oblique scanning micro-thruster includes a shell, a cover plate, a Laval nozzle, a laser source, a motor, a push rod, a fixing rod, and a base. The shell is a hollow shell with an open top, and gel propellant is filled inside the shell. The propellant has a bevel near the Laval nozzle; a cover plate is sealed on the top surface of the outer shell; one end of the outer shell is sealed to the Laval nozzle; a laser source is fixedly installed inside the fuselage behind the mounting slot and located outside the cover plate. The laser beam emitted by the laser source passes through the cover plate at an angle to the axis of the gel propellant and irradiates the bevel of the gel propellant; a motor is fixed on the base, and the power output end of the motor is connected to the push rod, which drives the push rod to push the gel propellant axially towards the Laval nozzle. The feed speed of the push rod is coupled with the ablation speed of the gel propellant by the laser source; the gel propellant is a photosensitive gel material that burns upon laser irradiation and extinguishes when the laser is turned off; the flight control system is electrically connected to the first thruster and the second thruster respectively, and is used to control the opening, closing and thrust of each thruster respectively.

[0006] Furthermore, the axes of the two mounting slots are at a 90° angle in the horizontal plane, and the thrust vectors of the two nozzles are perpendicular to each other in the horizontal plane.

[0007] Furthermore, the laser oblique scanning micro thruster also includes two fixed rod limit keys, which are fixed to the base respectively, and the two ends of the fixed rod are fixed to the two fixed rod limit keys respectively.

[0008] Furthermore, the laser oblique scanning micro-pusher also includes a push rod positioning key, which is fixedly connected to the housing. The push rod positioning key has a keyway inside, and the push rod can slide axially within the keyway of the push rod positioning key. The push rod positioning key restricts the circumferential rotation of the push rod.

[0009] Furthermore, the laser beam emitted by the laser source makes an angle of 110° to 130° with the axis of the gel propellant.

[0010] Furthermore, the laser beam emitted by the laser source makes an angle of 120° with the axis of the gel propellant.

[0011] Furthermore, the slope angle of the gel propellant is 30° to 60°.

[0012] Furthermore, the Laval nozzle is an axial flow structure that converges first and then diverges, with a convergence angle of 20° to 30° in the convergent section and an inner diameter of 1 mm in the throat.

[0013] Furthermore, the cover plate is made of quartz glass with a laser transmittance of not less than 95%; a sealing ring is sandwiched between the cover plate and the outer shell, and the cover plate and the outer shell are connected by threaded fasteners.

[0014] Furthermore, the motor is a stepper motor or a servo motor, and the motor is mounted on the end of the fixed rod away from the push rod.

[0015] Compared with the prior art, the present invention has the following advantages: (1) This invention adopts a working mode in which the laser source is stationary and the gel propellant is actively fed. The motor drives the push rod to move the gel propellant axially towards the Laval nozzle at a constant speed. The feed speed of the push rod is coupled with the ablation speed of the gel propellant by the laser. The push amount of the push rod is synchronized with the ablation amount of the gel propellant. The laser always irradiates the newly exposed surface of the gel propellant, ensuring continuous and stable combustion. Compared with the existing technology where the laser source moves to scan the working surface and speed matching is difficult, this invention solves the speed coupling problem at its root and achieves stable thrust output.

[0016] (2) This invention employs a method of obliquely irradiating the inclined surface of the gel propellant with a laser. The laser beam passes through the cover plate at an angle of 110° to 130° with the axial direction of the gel propellant and irradiates the inclined surface of the gel propellant. This increases the ablation contact area between the laser and the gel propellant, achieving radial full-section ablation, avoiding local incomplete combustion, and improving the utilization rate and specific impulse of the working propellant. At the same time, the oblique irradiation causes the combustion products to be discharged unidirectionally along the Laval nozzle direction, fundamentally avoiding the contamination of the optical window by the combustion products.

[0017] (3) This invention uses a photosensitive gel propellant that ignites upon laser irradiation, extinguishes upon laser shutdown, and can be reignited upon irradiation again. Combined with the coupled control of the push rod feed speed and ablation rate, instantaneous start / stop and flexible adjustment of thrust are achieved. By adjusting the laser power and motor speed, the thrust magnitude can be controlled to meet the needs of different operating conditions.

[0018] (4) The present invention provides a dual constraint structure by using a fixed rod to provide axial guidance and a push rod positioning key to restrict circumferential rotation, which together ensures the coaxiality of the feed when the push rod pushes the gel propellant, avoids the ablation slope of the gel propellant from deflecting the laser beam irradiation position, and ensures the stability and consistency of the combustion process.

[0019] The present invention will now be further described with reference to the accompanying drawings. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the rear view structure of a rotary-wing unmanned aerial vehicle.

[0021] Figure 2 This is a half-section front view of the overall structure of the laser oblique scanning micro-thruster.

[0022] Figure 3 This is a top view of the overall structure of a laser oblique scanning micro-thruster.

[0023] In the diagram: 1. Fixed rod; 2. Fixed rod limit key; 3. Motor; 4. Base; 5. Push rod; 6. Gel propellant tank; 7. Outer shell; 8. Laval nozzle; 9. Sealing ring; 10. Cover plate; 11. Laser source; 12. Push rod positioning key. Detailed Implementation

[0024] 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.

[0025] This invention provides a rotary-wing unmanned aerial vehicle (UAV) equipped with a laser oblique scanning micro-thruster, which is used to generate direct control torque through the micro-thruster installed at the tail of the fuselage in complex airflow environments, hovering or high-maneuver flight conditions, so as to make fine adjustments to the flight attitude.

[0026] Thrust layout and installation; refer to Figure 1 The rotary-wing UAV has a mounting slot on each side of its tail section, with the axes of the two slots forming a 90° angle in the horizontal plane. The shaded area in the diagram indicates the location of the mounting slots. Each mounting slot houses a laser-guided oblique scanning micro-thruster, designated as the first thruster and the second thruster. The nozzle of the first thruster faces one side of the tail section, while the nozzle of the second thruster faces the other side. The thrust vectors of the two nozzles are perpendicular to each other in the horizontal plane. Both thrusters are electrically connected to the UAV's flight control system via signal lines. The flight control system controls the activation, deactivation, and thrust magnitude of each thruster according to attitude control commands.

[0027] The considerations for adopting the above layout are as follows: Two thrusters are fixedly installed at the tail of the fuselage at a 90° angle. By independently adjusting the thrust magnitude and start / stop of each thruster, thrust vectors in different directions can be synthesized in the horizontal plane. When the two thrusters work simultaneously with the same thrust, the resultant force direction forms a 45° angle with the longitudinal axis of the fuselage, generating a yaw moment about the center of gravity. When the two thrusters work differentially with different thrusts, the magnitude and direction of the yaw moment can be adjusted. The two thrusters do not require a mechanical servo gimbal, resulting in a simple and compact structure. As a supplement to rotor attitude control, the thrusters provide high-precision torque output with millisecond-level response in the yaw channel, where fine adjustment of the rotor is difficult, enabling precise fine-tuning of the yaw angle. The forward, backward, left, and right translation, as well as pitch and roll movements of the rotary-wing UAV, are completed by the rotor system. The thrusters work in conjunction with the rotor system to achieve full-channel attitude control of the aircraft.

[0028] Laser-driven oblique scanning micro-thruster structure; the laser-driven oblique scanning micro-thruster adopts an oblique scanning working mode with a fixed laser source and active feeding of gel propellant. (Refer to...) Figure 2 and Figure 3 Each laser oblique scanning micro thruster includes a fixed rod 1, a fixed rod limit key 2, a motor 3, a base 4, a push rod 5, a gel propellant tank 6, a shell 7, a Laval nozzle 8, a sealing ring 9, a cover plate 10, a laser source 11, and a push rod positioning key 12.

[0029] Reference Figure 2 The fixing rod 1 is an axially extending rod-shaped structure. There are two fixing rod limiting keys 2, each fixed to the base 4. Both ends of the fixing rod 1 are fixed to the two fixing rod limiting keys 2. The base 4 and the fixing rod limiting keys 2 are rigidly fixed together using threaded fasteners. The fixing rod limiting key 2 is block-shaped; its lower part is fixed to the base 4, and its upper part mates with the end of the fixing rod 1, used to fix the fixing rod 1 to the base 4 and limit its axial movement and radial displacement.

[0030] The push rod 5 passes through the fixed rod 1 and is coaxially arranged with it, allowing it to slide freely axially within the fixed rod 1. The fixed rod 1 is a hollow tubular structure open at both ends, with an inner diameter larger than the outer diameter of the push rod 5, forming a clearance fit that reduces sliding resistance while ensuring guiding accuracy. The fixed rod 1 provides axial guidance for the push rod 5, limiting its radial deflection. The fixed rod 1 is made of carbon steel, which is heat-resistant and has high structural strength, capable of withstanding the high-pressure impact and high-temperature environment within the combustion chamber.

[0031] Motor 3 is mounted on the end of fixed rod 1 away from push rod 5. The output shaft of motor 3 is connected to push rod 5 for transmission, and motor 3 is used to drive push rod 5 to move linearly along the axial direction of fixed rod 1. Motor 3 can be a stepper motor or a servo motor. Stepper motors precisely adjust the feed speed of push rod 5 by controlling the pulse frequency, while servo motors achieve higher precision speed control through closed-loop feedback.

[0032] The push rod positioning key 12 is located at the end of the push rod 5 near the housing 7. The push rod positioning key 12 is fixedly connected to the housing 7 by threads. The push rod positioning key 12 has a keyway, within which the push rod 5 can slide axially. The push rod positioning key 12 restricts the circumferential rotation of the push rod 5. The dual constraint structure, with the fixed rod 1 providing axial guidance and the push rod positioning key 12 restricting circumferential rotation, ensures the coaxiality of the feed when the push rod 5 pushes the gel propellant, preventing the ablation slope of the gel propellant from deviating from the laser beam irradiation position of the laser source 11.

[0033] Reference Figure 2 One end of the outer casing 7 is threadedly sealed to the Laval nozzle 8. The outer casing 7 is a hollow shell with an open top, and the hollow space inside the outer casing 7 is the gel propellant tank 6. The cover plate 10 is placed on the top surface of the outer casing 7, completely sealing the outer casing 7. A sealing ring 9 is sandwiched between the outer casing 7 and the cover plate 10. The cover plate 10 and the outer casing 7 are connected by threaded fasteners. The sealing ring 9 undergoes elastic deformation under the clamping force, achieving an optical window seal for the combustion chamber. The sealing ring 9 is made of high-temperature resistant fluororubber to prevent high-temperature combustion gases from escaping from the contact surface between the cover plate 10 and the outer casing 7, reducing the risk of damage to the cover plate 10 due to uneven local pressure.

[0034] Reference Figure 2 and Figure 3 The gel propellant is filled in the gel propellant tank 6, located between the push rod 5 and the cover plate 10. The gel propellant has a cylindrical structure, and the diameter of the cylinder is adapted to the inner diameter of the gel propellant tank 6. The end of the gel propellant near the Laval nozzle 8 has a bevel with an inclination angle of 30° to 60°. The gel propellant is a photosensitive gel material; it ignites upon laser irradiation, extinguishes when the laser is turned off, and can be re-ignited upon re-irradiation. The gel propellant is gel-like, has stable combustion performance, and is easy to store and fill. The gel propellant is filled into the gel propellant tank 6 in one go. During filling, the thruster is removed from the mounting slot, the cover plate 10 is removed, the gel propellant is loaded into the gel propellant tank 6, the cover plate 10 is then installed and the sealing ring 9 is tightened, and the thruster is reinstalled into the mounting slot. At this time, the light outlet of the laser source 11 automatically aligns with the cover plate 10. The inner diameter of the gel propellant tank 6 is matched with the diameter of the gel propellant column to prevent radial displacement of the gel propellant during combustion and feeding.

[0035] Reference Figure 2 The laser source 11 is fixedly installed inside the machine body behind the mounting slot, with its emission direction facing the thruster cover plate 10. When the thruster is installed in the mounting slot, the laser beam emitted by the laser source 11 passes through the cover plate 10 at an angle of 110° to 130° with the axial direction of the gel propellant, irradiating the inclined surface of the gel propellant; preferably, this angle is 120°. The laser source 11 remains in a fixed position. When the thruster is disassembled and replaced, the laser source 11 remains inside the machine body and is not removed with the thruster. The cover plate 10 is made of quartz glass and serves as the optical window for laser transmission, with a laser transmittance of not less than 95%, ensuring efficient transmission of laser energy to the surface of the gel propellant. When the laser beam emitted by the laser source 11 irradiates the inclined surface of the gel propellant at an angle of 110° to 130° with the axial direction of the gel propellant, the gel propellant rapidly ignites and burns due to its photosensitive properties, generating high-temperature, high-pressure combustion gas. When the laser source 11 stops irradiating, the gel propellant immediately extinguishes; it can be reignited by irradiation again. The laser source 11 is fixed in position, and the motor 3 drives the push rod 5 to push the gel propellant along the axial direction towards the Laval nozzle 8. The feed speed of the push rod 5 is coupled with the ablation speed of the gel propellant by the laser source 11 to ensure continuous and stable combustion. The laser always irradiates the newly exposed surface of the gel propellant.

[0036] Reference Figure 2 The Laval nozzle 8 is an axial-flow structure with a convergent-divergent configuration. The convergence angle of the convergent section is 20° to 30°, the minimum inner diameter of the throat is 1 mm, the inner diameter of the gel propellant side connected to the outer shell 7 is 6 mm, and the inner diameter of the exhaust side is 6.5 mm. The high-temperature, high-pressure gas generated by the combustion of the gel propellant enters the nozzle from the gel propellant side, is compressed and accelerated to sonic speed in the convergent section, and then expanded and accelerated to supersonic speed in the divergent section before being ejected at high speed from the exhaust side to generate thrust. If the convergence angle is too small, the nozzle length will increase and the wall friction loss will increase; if the convergence angle is too large, the risk of airflow separation will increase. A convergence angle of 20° to 30° is selected within this range to balance acceleration efficiency and structural compactness.

[0037] Work process The thruster operates as follows: Motor 3 drives push rod 5 forward along the axis of fixed rod 1, pushing the gel propellant towards the Laval nozzle 8 at a constant speed. Laser source 11 is fixedly installed inside the machine body behind the mounting slot, its position fixed. The emitted laser beam forms a 120° angle with the axis of the gel propellant. After being irradiated by the laser, the gel propellant ignites and burns, generating high-temperature, high-pressure gas. The gas converges and then diverges through the Laval nozzle 8, accelerating to supersonic speed before being ejected, generating thrust. The feed speed of push rod 5 is coupled with the ablation rate of the gel propellant by laser source 11, and the propulsion amount of push rod 5 is synchronized with the ablation amount of the gel propellant. The laser always irradiates the newly exposed surface of the gel propellant, ensuring continuous and stable combustion. When it is necessary to stop propulsion, laser source 11 is turned off, and the gel propellant immediately extinguishes. Turning laser source 11 back on reignites combustion. Combustion products are discharged from the Laval nozzle 8. The thrust can be adjusted by regulating the laser power and motor speed. When the gel propellant is consumed, the thruster is removed from the mounting slot, the cover plate 10 is removed and the gel propellant is refilled, and then the thruster is reinstalled into the mounting slot. The laser source 11 is kept inside the machine body.

[0038] During UAV flight, the rotor system is responsible for the aircraft's translation (forward, backward, left, and right) as well as pitch and roll. When fine-tuning of the yaw direction is required, the flight control system sends commands to the first and second thrusters based on the yaw angle deviation sensed by the gyroscope. When both thrusters operate simultaneously with the same thrust, the two thrust vectors combine in the horizontal plane, with the resultant force forming a 45° angle with the longitudinal axis of the aircraft, generating a yaw moment about the center of gravity. When the two thrusters operate differentially with different thrusts, adjusting the thrust ratio changes the direction of the resultant force, producing yaw moments of different magnitudes and directions. A single thruster operating alone can also produce a yaw effect. Through the coordinated control of the two thrusters, precise fine-tuning of the UAV's yaw angle can be achieved.

[0039] Theoretical derivation of application effects This scheme achieves precise attitude control of the yaw channel by synthesizing the thrust vectors of two thrusters. The two thrusters are respectively mounted on either side of the tail of the rotary-wing UAV, with their thrust vectors forming a 90° angle in the horizontal plane. The thrust direction of the first thruster is along the positive Y-axis of the body coordinate system, and the thrust direction of the second thruster is along the positive X-axis of the body coordinate system. The thrust of a single thruster is F.

[0040] Yaw control analysis: When both thrusters operate simultaneously with the same thrust in the same direction, the resultant force generated forms a 45° angle with the fuselage axis in the horizontal plane, producing a yawing moment about the center of gravity. When the two thrusters operate differentially with different thrusts, the magnitude and direction of the yawing moment can be adjusted to achieve bidirectional fine adjustment of the yawing angle.

[0041] The following quantitative analysis 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 × t = 0.001 N / s. For ease of calculation, the following analysis takes the cumulative impulse of 10 consecutive pulses as 0.01 N / s.

[0042] Scenario: A micro-sized rotary-wing drone, weighing 1 kg and with a wheelbase of 0.5 m.

[0043] Translational effect analysis: The cumulative impulse of 10 consecutive pulses is 0.01 N / s. The velocity increment ΔV is derived from the momentum theorem: ΔV = cumulative impulse / aircraft mass = 0.01 / 1 = 0.01 m / s². The thrust within a single pulse duration of 10 milliseconds is 0.1 N, and the instantaneous acceleration a = thrust / mass = 0.1 / 1 = 0.1 m / s². The thruster contributes relatively little to the translational motion; its main function is concentrated on fine-tuning the attitude in the yaw channel. The translational motion is primarily accomplished by the rotor system.

[0044] Attitude Effect Analysis: The thruster is mounted at the tail of the fuselage, 0.25 meters from the center of gravity lever arm L. The moment of inertia I of the aircraft about the yaw axis is approximately 0.02 kg·m². The impulse moment of a single pulse = thrust × lever arm × pulse time = 0.1 × 0.25 × 0.01 = 0.00025 N·m·s. The angular velocity increment Δω generated by a single pulse = impulse moment / I = 0.00025 / 0.02 = 0.0125 radians / second. The cumulative angular velocity increment of 10 consecutive pulses is 0.125 radians / second, corresponding to a yaw angular velocity of approximately 7.2° / second. Considering the effect of aerodynamic damping in actual flight, the achievable yaw angle correction range under continuous control is approximately 5° to 30°, with the specific value depending on real-time operating conditions such as flight speed and atmospheric density.

[0045] As the above analysis shows, this thruster can generate effective yaw control torque on micro-sized rotary-wing UAVs. The two thrusters are installed at a 90° angle, and their respective thrust magnitude and start / stop are adjusted via purely electronic control, achieving millisecond-level response and precise fine-tuning of the yaw angle. This compensates for the lag and insufficient accuracy of the rotor system in the yaw channel, making it particularly suitable for micro-sized rotary-wing UAV platforms with high attitude control precision requirements.

[0046] In this embodiment, a miniature rotary-wing UAV with a wheelbase of 0.5 meters and a mass of 1 kilogram is used as the application object. Two laser-guided oblique scanning micro-thrusters are installed on either side of the tail section of the UAV, with the thrust vectors of the two thrusters forming a 90° angle in the horizontal plane. The gel propellant is a photosensitive gel material, filled in the gel propellant tank 6. The laser source 11 has an angle of 120° with the axis of the gel propellant, and the laser power is 30 watts. Motor 3 is a stepper motor, and the feed speed of the push rod 5 is coupled with the laser ablation speed. When the UAV encounters a lateral gust while hovering, the flight control system, based on the yaw angle deviation sensed by the gyroscope, controls the two thrusters to work differentially, generating a yaw correction torque. The UAV completes the yaw angle correction within 0.5 seconds, with a correction accuracy within 1°. After the correction is completed, the flight control system controls the laser source 11 to shut down, and the thrusters stop working. When the gel propellant is depleted, the cover plate 10 can be removed to refill the gel propellant.

[0047] 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 rotary-wing unmanned aerial vehicle equipped with a laser oblique scanning micro-thruster, characterized in that, include: The fuselage, first thruster, second thruster, and flight control system, among which, There is a mounting slot on each side of the tail of the fuselage, and the axes of the two mounting slots are at a 90° angle in the horizontal plane; Both the first and second thrusters are laser oblique scanning micro thrusters, which are fixedly installed in two mounting slots respectively. The nozzle of the first thruster faces one side of the tail of the fuselage, and the nozzle of the second thruster faces the other side of the tail of the fuselage. The thrust vector directions of the two nozzles are perpendicular to each other in the horizontal plane. The laser oblique scanning micro thruster includes a housing (7), a cover plate (10), a Laval nozzle (8), a laser source (11), a motor (3), a push rod (5), a fixing rod (1), and a base (4); The outer shell (7) is a hollow shell with an open top surface. Gel propellant is filled inside the outer shell (7). The end of the gel propellant near the Laval nozzle (8) is provided with a slope. The cover plate (10) is sealed on the top surface of the outer casing (7); One end of the outer casing (7) is sealed to the Laval nozzle (8); The laser source (11) is fixedly installed inside the body behind the mounting slot and is located outside the cover plate (10). The laser beam emitted by the laser source (11) passes through the cover plate (10) at an oblique angle to the axis of the gel propellant and irradiates the inclined surface of the gel propellant. The motor (3) is fixed on the base (4). The power output end of the motor (3) is connected to the push rod (5) for transmission. The push rod (5) is driven to push the gel propellant in the direction of the Laval nozzle (8) along the axial direction. The feed speed of the push rod (5) is coupled with the ablation speed of the gel propellant by the laser source (11). The gel propellant is a photosensitive gel material that ignites upon laser irradiation and extinguishes when the laser is turned off. The flight control system is electrically connected to the first and second thrusters respectively, and is used to control the opening, closing and thrust magnitude of each thruster respectively.

2. A rotary-wing UAV equipped with a laser oblique scanning micro-thruster according to claim 1, characterized in that, The axes of the two mounting slots are at a 90° angle in the horizontal plane, and the thrust vectors of the two nozzles are perpendicular to each other in the horizontal plane.

3. A rotary-wing UAV equipped with a laser oblique scanning micro-thruster according to claim 1, characterized in that, The laser oblique scanning micro thruster also includes a fixed rod limit key (2). There are two fixed rod limit keys (2), which are fixed on the base (4) respectively. The two ends of the fixed rod (1) are fixed on the two fixed rod limit keys (2) respectively.

4. A rotary-wing UAV equipped with a laser oblique scanning micro-thruster according to claim 1, characterized in that, The laser oblique scanning micro thruster also includes a push rod positioning key (12), which is fixedly connected to the outer shell (7). The push rod positioning key (12) has a keyway inside, and the push rod (5) can slide axially in the keyway of the push rod positioning key (12). The push rod positioning key (12) restricts the circumferential rotation of the push rod (5).

5. A rotary-wing UAV equipped with a laser oblique scanning micro-thruster according to claim 1, characterized in that, The laser beam emitted by the laser source (11) has an angle of 110° to 130° with the axis of the gel propellant.

6. A rotary-wing unmanned aerial vehicle equipped with a laser oblique scanning micro-thruster according to claim 5, characterized in that, The laser beam emitted by the laser source (11) has an angle of 120° with the axis of the gel propellant.

7. A rotary-wing unmanned aerial vehicle equipped with a laser oblique scanning micro-thruster according to claim 1, characterized in that, The slope angle of the gel propellant is 30° to 60°.

8. A rotary-wing unmanned aerial vehicle equipped with a laser oblique scanning micro-thruster according to claim 1, characterized in that, The Laval nozzle (8) is an axial flow structure that converges first and then diverges. The convergence angle of the convergence section is 20° to 30° and the inner diameter of the throat is 1 mm.

9. A rotary-wing unmanned aerial vehicle equipped with a laser oblique scanning micro-thruster according to claim 1, characterized in that, The cover plate (10) is made of quartz glass with a laser transmittance of not less than 95%; a sealing ring (9) is sandwiched between the cover plate (10) and the outer shell (7), and the cover plate (10) and the outer shell (7) are connected by threaded fasteners.

10. A rotary-wing unmanned aerial vehicle equipped with a laser oblique scanning micro-thruster according to claim 1, characterized in that, The motor (3) is a stepper motor or a servo motor, and the motor (3) is installed on the end of the fixed rod (1) away from the push rod (5).

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