A flying patrol gun system and its trajectory correction strategy

Abstract

The application is a kind of patrol flying gun system and its trajectory correction strategy. It includes unmanned aerial vehicle, gimbal structure and no-bracket gun; the gimbal structure includes gun clamp, target information acquisition device, pitch shaft mechanism, support mechanism, yaw shaft mechanism, suspension mechanism and firing mechanism; the ejection window of the no-bracket gun is away from the clamp, facing the ground, fixed on the gun clamp of the gimbal structure, the gimbal structure is connected with the unmanned aerial vehicle platform through the suspension mechanism, the gun clamp is provided with the pitch shaft mechanism, the pitch shaft mechanism is provided with the yaw shaft mechanism, and the suspension mechanism is arranged on the yaw shaft mechanism; the support mechanism is arranged on the side of the pitch shaft mechanism, used for reducing the influence of the recoil force on the output shaft of the rudder of the pitch shaft mechanism. The application reduces the vertical size of the overall structure of the gimbal, shortens the action line of the recoil force of the gun firing and the center of mass of the patrol flying gun, reduces the influence of the recoil force on the flight control of the unmanned aerial vehicle platform, and enhances the driving effect of the rudder.

Description

Technical Field

[0001] This invention belongs to the field of aerial unmanned platform weapons, specifically relating to a loitering gun system and its ballistic correction strategy. Background Technology

[0002] Unmanned aerial vehicles (UAVs) are widely used in both military and civilian fields due to their low cost, high functionality, strong mobility, ease of use, and adaptability. In urban warfare environments, UAVs can improve our reconnaissance range. Building on this, to enhance the long-range strike capabilities of individual soldiers and squads, a reconnaissance-strike integrated weapon based on UAVs has been proposed—a UAV weapon with a gimbal-mounted firearm, also known as a loitering gun. Loitering drones can simultaneously perform reconnaissance and strike missions, acquiring target information through high-definition cameras and sensors, and equipped with a controllable firearm system for precise strikes.

[0003] In current technology, firearms are mostly mounted vertically on drone platforms. Due to the height and dimensions of the firearm, a large space needs to be left below the drone. With this mounting method, the distance between the recoil line of the firearm and the center of gravity of the loitering gun is relatively large, which is not conducive to the drone's flight control system's adjustment of the loitering gun's movement. Furthermore, when the firearm is installed, the recoil direction does not intersect with the rotation axis, which will generate additional recoil torque on the motor output shaft, affecting the motor's lifespan. Additionally, there is a lack of strategies for engaging moving targets while the loitering gun is in motion. Summary of the Invention

[0004] The purpose of this invention is to provide a UAV gimbal mechanism that can be side-mounted with firearms, a loitering gun system including the gimbal mechanism, and on this basis, to propose a strike strategy that takes into account the loitering gun and the movement of the target.

[0005] The technical solution to achieve the purpose of this invention is: a loitering gun system, including a drone, a gimbal structure and a bullpup gun;

[0006] The gimbal structure includes a gun clamp, a target information acquisition device, a pitch axis mechanism for adjusting the gun's pitch angle, a support mechanism, a yaw axis mechanism for adjusting the gun's azimuth angle, a suspension mechanism, and a firing mechanism.

[0007] The ejection port of the bullpup firearm is fixed to the firearm fixture of the gimbal structure, facing away from the clamp and towards the ground. The gimbal structure is connected to the UAV platform through a suspension mechanism. The firearm fixture is equipped with a pitch axis mechanism, and the pitch axis mechanism is equipped with a yaw axis mechanism. The suspension mechanism is set on the yaw axis mechanism. The support mechanism is set on the side of the pitch axis mechanism to reduce the influence of recoil on the servo output shaft of the pitch axis mechanism. The firing mechanism is used to activate the trigger of the bullpup firearm.

[0008] Furthermore, the gun clamp includes a side plate, two rear support pins, a rear retaining ring, a clamping plate, a front retaining ring, a front support pin, a stop lever, a rotating handle, a wing nut, a clamping block, and a double-ended stud.

[0009] The sights of bullpup firearms have front and rear bevels for positioning; the middle part of the rotating handle and the side plate are connected by bolts, and there is axial clearance between the rotating handle and the side plate, so that the rotating handle can rotate around the bolt axis; the two ends of the rotating handle are provided with rotating handle stop I and rotating handle stop II.

[0010] The clamping plate is connected and fixed to the side plate of the clamp. The clamping plate has a boss with a threaded hole. A double-ended stud is fixed to the clamping plate by a threaded connection at one end and a wing nut is screwed on the other end. The clamping block is fitted onto the double-ended stud. One side of the clamping block is an inclined surface that mates with the rear inclined surface of the gun sight.

[0011] The gun ejection port is placed on the side plate of the clamp with its back facing away from the clamp. Its lateral position is determined by two rear support pins and a front support pin. The front and rear retaining rings are installed on the handguard and stock of the gun, respectively, and are fixed to the side plate of the clamp with screws.

[0012] The front bevel of the bullpup rifle sight abuts against the stop lever, the rear bevel abuts against the clamping block, and the rear side of the clamping block abuts against the stop lever I on the rotating handle. Adjust the degree of screwing of the wing nut on the stud, adjust the rotation angle of the rotating handle, so that the stop lever II of the rotating handle abuts against the rear side of the rifle grip, determine the front-back and up-down position of the rifle, and clamp it.

[0013] Furthermore, the target information acquisition device includes a laser rangefinder and a camera module. The laser rangefinder has rectangular slots at the four corners of its bottom edge and is fixed to the side of the clamp side plate with screws.

[0014] Furthermore, the pitch axis mechanism includes servo I, servo mounting housing, sleeve I, circular rocker arm, deep groove ball bearing I, bracket, deep groove ball bearing II, end cover I, steering stick I, elevation shaft and steering stick II;

[0015] The lower ends of steering handle I and steering handle II are fixed in the middle groove on the side of the clamp side plate, and the upper ends are installed on the high and low shafts through the shaft hole;

[0016] The high and low shafts are hollow shafts with two symmetrically arranged planes on their sides, which mate with the two planes of the shaft holes on steering handle I and steering handle II to transmit torque.

[0017] The elevation and depression shaft is mounted on the bracket via deep groove ball bearings I and II. The bracket on the side of deep groove ball bearing II is equipped with end cap I. The servo motor mounting housing is fixed on the other side of the bracket. Sleeve I is installed between the servo motor mounting housing and deep groove ball bearing I. Servo motor I is fixed on the servo motor mounting housing. The output shaft of servo motor I is connected to a circular swing arm. The circular swing arm is fixedly connected to one end of the elevation and depression shaft. The rotation of the elevation and depression shaft is driven by servo motor I, thereby driving the rotation of the firearm clamp and adjusting the firearm's elevation and depression angle.

[0018] Furthermore, the support mechanism includes a servo motor II, a sleeve II, a deep groove ball bearing III, a cantilever I, a cam I, a roller I, a roller cantilever I, a support shaft, a roller cantilever II, a roller II, a cam II, a cantilever II, a deep groove ball bearing IV, and an end cap II.

[0019] Cantilever I and cantilever II are connecting parts for the support mechanism and the pitch axis mechanism, and cantilever I and cantilever II are fixed on the bracket;

[0020] Cam I and Cam II are symmetrically designed, and their follower motion laws are the same. The cam is provided with a hole and an inner groove that mates with the roller. The width of the inner groove is the same as the diameter of the roller. The distance between each point on the axis of the inner groove and the center of the hole satisfies the follower motion law of the cam. The inner side of the hole is designed with a symmetrical plane. The cam is mounted on the support shaft through an interference fit with the shaft hole. The cam mounting point on the support shaft is provided with a symmetrical plane corresponding to the inner side plane of the cam hole, which is used to transmit torque and drive the cam to rotate.

[0021] The support shaft is mounted on the cantilever at both ends via deep groove ball bearings III and IV. End cap II is fixed on cantilever II to determine the position of deep groove ball bearing IV. Servo II is fixed on cantilever I. Sleeve II is installed between servo II and deep groove ball bearing III.

[0022] A support shaft is mounted on one end of cantilever I and is equipped with an internal gear. The output shaft of servo motor II meshes with the internal gear to drive the support shaft to rotate.

[0023] Roller cantilever I and roller cantilever II are fixed to the side plate. Cylindrical bosses are provided on the cantilever. Roller I and roller II are respectively fitted onto the bosses of the two roller cantilevers and can rotate around the axis of the bosses.

[0024] Furthermore, when the angular displacement γ of the high and low shafts and the angular displacement γ′ of the support shaft satisfy γ′=7.5·(γ+15°), the shape of the inner groove of the cam ensures that the motion law of the follower of the cam makes the cam's stroke equal to the distance between the axis of the support shaft and the axis of the roller.

[0025] Furthermore, the yaw axis mechanism includes a servo motor III, a servo motor mounting plate, a swivel arm, a sleeve III, a deep groove ball bearing V, a steering shaft, a thrust ball bearing, and a housing.

[0026] The yaw axis mechanism is located above the pitch axis mechanism, and the directional axis is the connecting part between the yaw axis mechanism and the pitch axis mechanism. The lower end of the directional axis is fixed to the bracket.

[0027] The interior of the housing is stepped, and the directional shaft is installed inside the housing via a deep groove ball bearing V and a thrust ball bearing. The servo mounting plate is fixed inside the housing, and a sleeve III is installed between the servo mounting plate and the housing.

[0028] Servo III is fixed on the servo mounting plate. The output shaft of servo III meshes with the internal gear on the swivel arm and is connected to the directional shaft through the swivel arm, driving the rotation of the directional shaft, thereby driving the movement of the pitch axis mechanism and the firearm clamp, and adjusting the firearm's position.

[0029] Furthermore, the suspension mechanism includes bolt assemblies, a drone base plate, vibration-damping rubber ball assemblies, and carbon fiber plates;

[0030] The suspension mechanism is the connection mechanism between the loitering gun gimbal and the drone platform. The bolt group is the connecting component. The shock-absorbing rubber ball group is evenly distributed on the upper and lower sides of the bottom edge of the shell. The bottom surface of the lower rubber ball is attached to the carbon fiber plate, and the top surface of the upper rubber ball is attached to the drone base plate. The bolt passes through the carbon fiber plate, the lower rubber ball, the bottom edge of the shell, the upper rubber ball, and the drone base plate in sequence, and is finally fixed by nuts and spring washers.

[0031] Furthermore, the firing mechanism includes a servo IV, a rocker arm, and a trigger lever;

[0032] Servo IV is fixed to the side plate of the clamp. The output shaft of servo IV meshes with the rocker arm gear and is fixed by screws. The trigger handle is fixed to the rocker arm. Servo IV drives the trigger handle to pull the trigger.

[0033] A ballistic correction strategy based on the above system, considering the target and the loitering gun's motion, includes the following steps:

[0034] Step (1): Establish a geographical system O g X g Y g Z g Taking the location of the loitering gun's center of mass at time T1 as the origin, OY g Perpendicular to the local horizontal plane, pointing upwards, it is usually defined as OX. g Pointing due north, OZ g Pointing due east;

[0035] Step (2): Establish the loitering gun body coordinate system OXYZ; the origin is located at the loitering gun's center of mass, the OX axis is located in the loitering gun's plane of symmetry and points towards the nose, the OY axis is located in the plane of symmetry and perpendicular to the OX axis and points towards the back of the aircraft, and the OZ conforms to the right-hand rule;

[0036] Step (3): Determine the location of the loitering gun in the geographic system O based on the GPS positioning device of the loitering gun UAV platform. g X g Y g Z g Flight speed

[0037] Step (4): Based on the flight speed of the loitering gun Determine the pitch angle θ1, roll angle φ1, and yaw angle ψ1 of the loitering gun's flight attitude;

[0038] Step (5): The loitering gun tracks and aims at the target using color recognition via the camera module of the target information acquisition device;

[0039] Step (6): Calculate the target velocity. At time T1, the relative distance between the target and the loitering gun is calculated using the laser rangefinder of the target information acquisition equipment, and the rotation angles of servo I (301) and servo III (501) are obtained at this time, thus determining the target's position vector in the body coordinate system OXYZ for the first time. At time T2, the process at time T1 is repeated to determine the target's position vector in the body coordinate system OXYZ for the second time. Based on the target's position vector in the machine's coordinate system OXYZ obtained at times T1 and T2, combined with the geographic coordinate system O where the loitering gun's center of mass is at times T1 and T2... g X g Y g Z g The location of the target in the geographic system O is calculated. g X g Y g Z g Speed ​​of movement

[0040] Step (7): Determine the response time of the loitering gun; Based on the motion law of the center of mass of the projectile in the air ballistics, the target position vector measured at time T2 is used as the ballistic parameter to determine the flight time of the projectile from the loitering gun firing and hitting the target, and then determine the total time Δt from the loitering gun from the firing command to the gimbal movement, and finally the time Δt of the projectile fired by the loitering gun to reach the target position, which is the response time of the loitering gun.

[0041] Step (8): Based on the loitering gun's movement speed obtained in step (3) The target's velocity obtained in step (6) Using the response time Δt of the loitering gun obtained in step (7), calculate and determine the position (x) of the target and the loitering gun in the geographic system OgXgYgZg at time T2+Δt. A ,y A ,z A);

[0042] Step (9): Based on the flight speed of the loitering gun obtained in step (3) Adjusting the barrel yaw angle corrects the initial velocity of the projectile, ensuring that the initial velocity direction lies within the vertical plane connecting the target and the muzzle, thus obtaining the projectile's initial velocity. and yaw angle ψ0;

[0043] Step (10): Based on the target and loitering gun at time T2+Δt obtained in step (8), in the geographic system O g X g Y g Z g Position in (x) A ,y A ,z A The initial velocity of the projectile obtained in step (9) and step (9) Based on the motion law of the projectile's center of mass in air ballistics, the projectile launch angle (pitch angle) θ0 is obtained;

[0044] Step (11): Based on the Euler angles of the loitering gun's flight attitude, pitch angle θ1, roll angle φ1 and yaw angle ψ1 obtained in step (5), the projectile's initial velocity yaw angle ψ0 obtained in step (9) and the projectile's launch angle θ0 obtained in step (10), the rotation angles θ2 = θ0 + θ1 of the elevation axis (310) in the loitering gun's gimbal pitch axis mechanism and ψ2 = ψ0 + ψ1 of the yaw axis structure of the direction axis (506) are obtained from time T2 to time T2 + Δt.

[0045] Compared with the prior art, the significant advantages of this invention are:

[0046] (1) The clamp and gimbal of the present invention can mount the gun to the side, which reduces the vertical dimension of the gimbal structure and reduces the space occupied by the gimbal after the weapon is mounted; at the same time, the line of action of the recoil force of the gun is shortened from the center of gravity of the loitering gun, which reduces the impact of the recoil on the flight control of the UAV platform.

[0047] (2) Based on the cam structure, this invention designs a support mechanism to address the problem of additional torque on the servo motor output shaft caused by the lack of intersection between the recoil direction of the firearm and the firearm attitude adjustment axis. This mechanism can reduce the impact of recoil on the servo motor output shaft and enhance the driving effect of the servo motor.

[0048] This invention employs a servo motor to directly drive the yaw and pitch axis mechanisms of the gimbal, directly controlling the gun's attitude. Based on the motion of the two-degree-of-freedom gimbal, a ballistic correction strategy considering the motion states of the loitering gun and the target is proposed. Under this strategy, the loitering gun performs relative distance detection with the target twice. Combining the loitering gun's motion states during these two detections, the target's motion state is analyzed. The time between the loitering gun receiving the firing command and the projectile hitting the target is taken as the system's total response time. This time is used to predict the positions of the loitering gun and the target after the response time, correcting the loitering gun's external ballistics and adjusting the gimbal motion, enabling the loitering gun to accurately strike the target while in motion. Attached Figure Description

[0049] Figure 1 This is a schematic diagram of the overall structure of the loitering gun gimbal of the present invention.

[0050] Figure 2 This is an exploded view of the gun clamp of the loitering gun gimbal of the present invention.

[0051] Figure 3 This is a schematic diagram of the target information acquisition device of the loitering gun gimbal of the present invention.

[0052] Figure 4 This is an exploded view of the pitch axis mechanism of the loitering gun gimbal of the present invention.

[0053] Figure 5 This is an exploded view of the support mechanism of the loitering gun gimbal of the present invention.

[0054] Figure 6 This is an exploded cross-sectional view of the yaw axis mechanism of the loitering gun gimbal of the present invention.

[0055] Figure 7 This is an exploded view of the suspension mechanism of the loitering gun gimbal of the present invention.

[0056] Figure 8 This is an exploded view of the firing mechanism of the loitering gun gimbal of the present invention.

[0057] Figure 9 This is a schematic diagram of the fixture side plate structure.

[0058] Figure 10 This is a schematic diagram of the rotary handle structure.

[0059] Figure 11 This is a schematic diagram of the high and low axis structure.

[0060] Figure 12 This is a schematic diagram of the support shaft structure.

[0061] Figure 13 This is the main view of the cam I structure.

[0062] Figure 14This is a flowchart of the ballistic correction strategy of the present invention.

[0063] Explanation of reference numerals in the attached figures:

[0064] 1-Firearm clamp, 2-Target information acquisition device, 3-Pitch axis mechanism, 4-Support mechanism, 5-Yaw axis mechanism, 6-Suspension mechanism, 7-Firing mechanism, 101-Side plate, 102-Rear support pin, 103-Rear shackle, 104-Clamping plate, 105-Front shackle, 106-Front support pin, 107-Lead lever, 108-Bolt, 109-Rotating handle, 110-Wing nut, 111-Clamping block, 11 2-Nut, 113-Spring Washer, 114-Double-ended Stud, 201-Laser Rangefinder, 202-Camera Module, 301-Servo Motor I, 302-Servo Motor Mounting Housing, 303-Sleeve I, 304-Circular Swing Arm, 305-Deep Groove Ball Bearing I, 306-Bracket, 307-Deep Groove Ball Bearing II, 308-End Cap I, 309-Steering Cylinder I, 310-High / Low Shaft, 311-Steering Cylinder II, 401 - Servo II, 402 - Sleeve II, 403 - Deep Groove Ball Bearing III, 404 - Cantilever I, 405 - Cam I, 406 - Roller I, 407 - Roller Cantilever I, 408 - Support Shaft, 409 - Roller Cantilever II, 410 - Roller II, 411 - Cam II, 412 - Cantilever II, 413 - Deep Groove Ball Bearing IV, 414 - End Cap II, 501 - Servo III, 502 - Servo Mounting plate, 503-Plum blossom swing arm, 504-Sleeve III, 505-Deep groove ball bearing V, 506-Directional shaft, 507-Thrust ball bearing, 508-Housing shell, 601-Bolt assembly, 602-UAV base plate, 603-Vibration damping rubber ball assembly, 604-Carbon fiber plate, 701-Servo IV, 702-Swing arm, 703-Trigger handle, 1091-Slewing handle stop lever I, 1092-Slewing handle stop lever II. Detailed Implementation

[0065] The present invention will now be described in further detail with reference to the accompanying drawings.

[0066] Combination Figure 1 A loitering gun's gimbal structure includes a gun clamp 1, a target information acquisition device 2, a pitch axis mechanism 3, a support mechanism 4, a yaw axis mechanism 5, a suspension mechanism 6, and a firing mechanism 7.

[0067] The pitch angle of the weapon is adjusted by the pitch axis mechanism 3, and the yaw angle is adjusted by the yaw axis mechanism 5.

[0068] Combination Figure 2The gun clamp 1 includes a side plate 101, two rear support pins 102, a rear retaining ring 103, a clamping plate 104, a front retaining ring 105, a front support pin 106, a stop bar 107, a bolt 108, a rotating handle 109, a wing nut 110, a clamping block 111, a nut 112, a spring washer 113, and a double-ended stud 114.

[0069] The clamping plate 104 is fixed to the side plate 101 of the fixture by screws, and has a boss with a threaded hole. A double-ended stud 114 is fixed to the clamping plate 104 by a threaded connection at one end, and a wing nut 110 is screwed onto the other end. The clamping block 111 is fitted onto the double-ended stud 114. Two rear support pins 102, a front support pin 106, and a stop bar are all fixed to the side plate 101 of the fixture by screws.

[0070] Combination Figure 2 , 9 10. The rotary handle is equipped with a stop lever I 1091 and a stop lever II 1092, and a boss with a through hole is provided in the middle. The clamp side plate 101 is provided with a through hole in the middle. The rotary handle 109 is installed on the clamp side plate 101 by a bolt group consisting of bolt 108, nut 112 and spring washer 113. During the initial installation, axial clearance is ensured between the rotary handle 109 and the side plate 101 so that the rotary handle 109 can rotate around the axis of bolt 108.

[0071] The ejection port of the firearm is placed on the side plate 101 of the clamp with its back facing away from the clamp. Its lateral position is defined by two rear support pins 102 and a front support pin 106. The front retaining ring 105 and the rear retaining ring 103 are respectively installed at the handguard and stock of the firearm and are fixed to the side plate 101 of the clamp by screws to provide clamping force for the firearm. The contact surfaces of the front retaining ring 105 and the rear retaining ring on the side plate 101 of the clamp are stepped, and the clamping force can be changed by adjusting the tightness of the screws on one side of the retaining ring.

[0072] The bullpup rifle 115 has a large distance between its sight baseline and the barrel axis, and its sight has front and rear sides for positioning. The front side abuts against the stop lever 107, and the rear side abuts against the clamping block 111. The front side of the clamping block 111 is beveled, which cooperates with the beveled side of the rear side of the rifle sight, and the rear side abuts against the stop lever I 1091 on the rotating handle 109. Adjusting the degree of screwing of the wing nut 110 onto the stud 114 adjusts the rotation angle of the rotating handle 109, so that the stop lever II 1092 on the rotating handle 109 abuts against the rear side of the rifle grip, thus determining the front-back and vertical position of the rifle and clamping it.

[0073] Combination Figure 3 The camera module 202 is bonded to the laser rangefinder 201. The laser rangefinder 201 has rectangular grooves at the four corners of its bottom edge and is fixed to the side plate 101 of the fixture with screws.

[0074] Combination Figure 3 , 4 11. The pitch axis structure includes a servo motor I 301, a servo motor mounting housing 302, a sleeve I 303, a circular swing arm 304, a deep groove ball bearing I 305, a bracket 306, a deep groove ball bearing II 307, an end cap I 308, a steering handle I 309, an elevation shaft 310, and a steering handle II 311. Steering handle I 309 and steering handle II 311 are connecting parts between the clamp 1 and the pitch axis mechanism 3. Their lower ends are connected by screws and fixed in the central groove of the clamp side plate 101, while their upper ends are mounted on the elevation shaft 310 through shaft holes.

[0075] The high-low shaft 310 is a hollow shaft structure with two symmetrically arranged planes on its side, which fit into the two planes of the upper inner hole of the steering handle I 309 and the steering handle II 311 to transmit torque. As the high-low shaft 310 rotates, the clamp 1 rotates around the axis of the high-low shaft 310.

[0076] The elevation shaft 310 is mounted on the bracket 306 via deep groove ball bearings I 305 and II 307. An end cap I 308 is fixed to one side of the bracket with screws, defining the position of deep groove ball bearing II 307. A servo mounting housing 302 is fixed to the other side of the bracket with screws. A sleeve I 303 is mounted on the servo mounting housing 302 and deep groove ball bearing I 305, defining the position of deep groove ball bearing I 305. A servo motor I 301 is fixed to the servo mounting housing 302 with screws. Its output shaft is connected to the internal gear core of the circular swing arm 304, and the circular swing arm 304 is fixed to the elevation shaft 310 with screws, directly driving the rotation of the elevation shaft 310, thereby driving the rotation of the clamp 1 and adjusting the weapon's position.

[0077] Combination Figure 1 , 3 4, 5, 12, 13, the support structure includes servo motor II 401, sleeve II 402, deep groove ball bearing III 403, cantilever I 404, cam I 405, roller I 406, roller cantilever I 407, support shaft 408, roller cantilever II 409, roller I 406, cam II 411, cantilever II 412, deep groove ball bearing IV 413, and end cap II 414. Cantilever I 404 and cantilever II 412 are connecting parts between support structure 4 and pitch axis mechanism 3. Support structure 4 is arranged behind pitch axis mechanism 3. The two cantilever arms are fixed to bracket 306 with screws.

[0078] Cam I405 and Cam II411 are symmetrically designed, and their follower motion laws are the same. The cams have a hole and an inner groove. The width of the inner groove is the same as the diameter of the roller, and the distances from each point on the axis of the inner groove to the center of the hole satisfy the follower motion law of the cam. The inner surface of the hole has a symmetrical plane, and the width of the inner groove is the same as the diameter of the roller. The cam is mounted on the support shaft 408 through an interference fit with the shaft hole. The cam mounting point on the support shaft 408 has a symmetrical plane corresponding to the inner plane of the cam hole, used to transmit torque and drive the rotation of the cam.

[0079] The support shaft 408 is mounted on the cantilever at both ends via deep groove ball bearings III 403 and IV 413. End cap II 414 is fixed to cantilever II 412 with screws, defining the position of deep groove ball bearing IV 413. Servo motor II 401 is fixed to cantilever I 404 with screws. Sleeve II 402 is installed between servo motor II 401 and deep groove ball bearing III 403 to adjust axial clearance and define the position of deep groove ball bearing III 403.

[0080] The support shaft 408 is mounted on one end of the cantilever I 404 and has an internal gear. The output shaft of the servo II 401 meshes with this internal gear, directly controlling the rotation of the support shaft 408.

[0081] Roller cantilever I 407 and roller cantilever II 409 are fixed to the side plate 101 of the fixture by screws. Cylindrical bosses are provided on the cantilever. Roller I 406 is respectively fitted onto the two roller cantilevers and can rotate around the axis of the roller cantilever boss. The rollers can perform translational and rotational movements within the cam groove.

[0082] When the angular displacement γ of the high and low axis 310° and the angular displacement γ′ of the support axis 408° satisfy γ′=7.5·(γ+15°), the shape of the inner groove of the cam ensures that the motion law of the follower of the cam can make the cam stroke equal to the distance between the axis of the support axis and the axis of the roller.

[0083] Combination Figure 1 , 4 6. The yaw axis mechanism 5 includes a servo motor III 501, a servo motor mounting plate 502, a swivel arm 503, a sleeve III 504, a deep groove ball bearing V 505, a directional shaft 506, a thrust ball bearing 507, and a housing 508. The yaw axis mechanism 5 is arranged above the pitch axis mechanism 3, and the directional shaft 506 is the connecting member between the yaw axis mechanism 5 and the pitch axis mechanism 3. The lower end of the directional shaft 506 is fixed to the bracket by screws.

[0084] The interior of housing 508 has a stepped layout. The steering shaft 506 is mounted inside housing 508 via a deep groove ball bearing V 505 and a thrust ball bearing 507. The servo mounting plate 502 is fixed inside housing 508 by screws. A sleeve III 504 is installed between the servo mounting plate 502 and housing 508 to adjust the axial clearance and determine the position of the deep groove ball bearing V 505.

[0085] Servo III 501 is fixed to servo mounting plate 502 with screws. Its output shaft meshes with the internal gear on the swivel arm 503, and is connected to the directional shaft 506 by screws through the swivel arm 503, directly driving the rotation of the directional shaft 506, thereby driving the movement of the pitch axis mechanism 3 and the clamp 1 to adjust the position of the firearm.

[0086] To ensure the installation space for servo III 501, sleeve III 504 is provided with a corresponding clearance groove.

[0087] Combination Figure 1 , 7 The suspension mechanism 6 includes a bolt assembly 601, a UAV base plate 602, a shock-absorbing rubber ball assembly 603, and a carbon fiber plate 604. The suspension mechanism 6 is the connection mechanism between the loitering gun gimbal and the UAV platform, with the bolt assembly 601 serving as the connecting component. The shock-absorbing rubber ball assembly 603 is evenly distributed on the upper and lower sides of the bottom edge of the outer shell 508. The bottom surface of the lower rubber ball is in contact with the carbon fiber plate 604, and the top surface of the upper rubber ball is in contact with the UAV base plate 602. The carbon fiber plate 604 has an equal number of holes evenly distributed according to the number of bolts in the bolt assembly 601. The UAV base plate 602 has evenly radially distributed rectangular grooves. The bolts pass sequentially through the carbon fiber plate 604, the lower rubber ball, the bottom edge of the outer shell 508, the upper rubber ball, and the UAV base plate 602, and are finally secured by nuts and spring washers.

[0088] Combination Figure 1 , 8 9. The firing mechanism 7 includes a servo motor IV 701, a swing arm 702, and a trigger handle 703. The servo motor IV 701 is fixed to the side plate 101 of the clamp with screws, and its output shaft meshes with the gear of the swing arm 702 and is fixed with screws. The trigger handle 703 is fixed to the swing arm 702 with screws. The servo motor IV 701 can directly drive the trigger handle 703 to pull the trigger.

[0089] Combination Figure 14 The ballistic correction strategy based on gimbal motion and considering the target and loitering gun motion includes the following steps:

[0090] Step (1): Establish a geographical system O g X g Y g Z gTaking the location of the loitering gun's center of mass at time T1 as the origin, OY g Perpendicular to the local horizontal plane, pointing upwards, it is usually defined as OX. g Pointing due north, OZ g Pointing due east;

[0091] Step (2): Establish the loitering gun's body coordinate system OXYZ. The origin is located at the loitering gun's center of mass, the OX axis is located in the loitering gun's plane of symmetry and points towards the nose, the OY axis is located in the plane of symmetry and perpendicular to the OX axis and points towards the back, and the OZ axis conforms to the right-hand rule;

[0092] Step (3): Determine the location of the loitering gun in the geographic system O based on the GPS positioning device of the loitering gun UAV platform. g X g Y g Z g Flight speed

[0093] Step (4): Based on the flight speed of the loitering gun Determine the pitch angle θ1, roll angle φ1, and yaw angle ψ1 of the loitering gun's flight attitude;

[0094] Step (5): The loitering gun tracks and aims at the target using color recognition via the camera module of the target information acquisition device;

[0095] Step (6): Calculate the target velocity. At time T1, the relative distance between the target and the loitering gun is calculated using the laser rangefinder of the target information acquisition equipment, and the rotation angles of servo I 301 and servo III 501 are obtained at this time, thus determining the target's position vector in the body coordinate system OXYZ for the first time. At time T2, the process at time T1 is repeated to determine the target's position vector in the body coordinate system OXYZ for the second time. Based on the target's position vector in the machine's coordinate system OXYZ obtained at times T1 and T2, combined with the geographic coordinate system O where the loitering gun's center of mass is at times T1 and T2... g X g Y g Z g The location of the target in the geographic system O is calculated. g X g Y g Z g Speed ​​of movement

[0096] Step (7): Determine the response time of the loitering gun. Based on the motion law of the projectile's center of mass in air ballistics, the target position vector measured at time T2 is used as the ballistic parameter to determine the flight time of the projectile from the loitering gun firing and hitting the target. Then, the total time Δt from the loitering gun receiving the firing command to the gimbal movement and finally the projectile reaching the target position is determined, which is the response time of the loitering gun.

[0097] Step (8): Based on the loitering gun's movement speed obtained in step (3) The target's velocity obtained in step (6) Using the response time Δt of the loitering gun obtained in step (7), calculate and determine the position (x) of the target and the loitering gun in the geographic system OgXgYgZg at time T2+Δt. A ,y A ,z A );

[0098] Step (9): Based on the flight speed of the loitering gun obtained in step (3) Adjusting the barrel yaw angle corrects the initial velocity of the projectile, ensuring that the initial velocity direction lies within the vertical plane connecting the target and the muzzle, thus obtaining the projectile's initial velocity. and yaw angle ψ0;

[0099] Step (10): Based on the target and loitering gun at time T2+Δt obtained in step (8), in the geographic system O g X g Y g Z g Position in (x) A ,y A ,z A The initial velocity of the projectile obtained in step (9) and step (9) Based on the motion law of the projectile's center of mass in air ballistics, the projectile launch angle (pitch angle) θ0 is obtained;

[0100] Step (11): Based on the Euler angles of the loitering gun's flight attitude, pitch angle θ1, roll angle φ1 and yaw angle ψ1 obtained in step (5), the projectile's initial velocity yaw angle ψ0 obtained in step (9) and the projectile's launch angle θ0 obtained in step (10), the rotation angles θ2 = θ0 + θ1 of the elevation axis 310 in the loitering gun's gimbal pitch axis mechanism 3 and ψ2 = ψ0 + ψ1 of the yaw axis structure 5 are obtained from time T2 to time T2 + Δt.

Claims

1. A loitering gun system, characterized in that, Including drones, gimbal structures, and bullpup firearms (115). The gimbal structure includes a gun clamp (1), a target information acquisition device (2), a pitch axis mechanism (3) for adjusting the gun's pitch angle, a support mechanism (4), a yaw axis mechanism (5) for adjusting the gun's yaw angle, a suspension mechanism (6), and a firing mechanism (7). The ejection port of the bullpup firearm (115) is fixed to the firearm fixture (1) of the gimbal structure, facing away from the firearm fixture and facing the ground. The gimbal structure is connected to the UAV through the suspension mechanism (6). The firearm fixture (1) is equipped with a pitch axis mechanism (3), and the pitch axis mechanism (3) is equipped with a yaw axis mechanism (5). The suspension mechanism (6) is installed on the yaw axis mechanism (5). The support mechanism (4) is installed on the side of the pitch axis mechanism (3) to reduce the influence of recoil on the servo output shaft of the pitch axis mechanism (3). The firing mechanism (7) is used to start the trigger of the bullpup firearm (115). The support mechanism (4) includes a servo motor II (401), a sleeve II (402), a deep groove ball bearing III (403), a cantilever I (404), a cam I (405), a roller I (406), a roller cantilever I (407), a support shaft (408), a roller cantilever II (409), a roller II (410), a cam II (411), a cantilever II (412), a deep groove ball bearing IV (413), and an end cap II (414). Cantilever I (404) and cantilever II (412) are the connecting parts of the support mechanism (4) and the pitch axis mechanism (3). Cantilever I (404) and cantilever II (412) are fixed on the bracket (306) of the pitch axis mechanism (3). Cam I (405) and Cam II (411) are symmetrically designed, and their follower motion laws are the same. Each cam is provided with a hole and an inner groove that mates with the roller. The width of the inner groove is the same as the diameter of the roller. The distance between each point on the axis of the inner groove and the center of the hole satisfies the follower motion law of the cam. The inner side of the hole is designed with a symmetrical plane. The cam is installed on the support shaft through an interference fit with the shaft hole. The cam mounting point on the support shaft (408) is provided with a symmetrical plane corresponding to the inner side plane of the cam hole, which is used to transmit torque and drive the cam to rotate. The support shaft (408) is mounted on cantilever I (404) and cantilever II (412) at both ends via deep groove ball bearing III (403) and deep groove ball bearing IV (413), respectively. End cap II (414) is fixed on cantilever II (412) to determine the position of deep groove ball bearing IV (413). Servo II (401) is fixed on cantilever I (404). Sleeve II (402) is installed between servo II (401) and deep groove ball bearing III (403). The support shaft (408) is mounted on one end of the cantilever I (404) and has an internal gear. The output shaft of the servo motor II (401) meshes with the internal gear to drive the support shaft (408) to rotate. Roller cantilever I (407) and roller cantilever II (409) are fixed on the side plate (101). A cylindrical boss is provided on the roller cantilever. Roller I (406) and roller II (410) are respectively fitted on the boss of the two roller cantilever and can rotate around the axis of the boss.

2. The system according to claim 1, characterized in that, The gun clamp (1) includes a side plate (101), two rear support pins (102), a rear retaining ring (103), a clamping plate (104), a front retaining ring (105), a front support pin (106), a stop bar (107), a rotating handle (109), a wing nut (110), a clamping block (111), and a double-ended stud (114). The sight of the bullpup firearm (115) has front and rear bevels for positioning; the middle part of the rotating handle (109) and the side plate (101) are connected by bolts, and there is axial clearance between the rotating handle (109) and the side plate (101), so that the rotating handle (109) can rotate around the bolt axis; the two ends of the rotating handle (109) are provided with rotating handle stop I (1091) and rotating handle stop II (1092). The clamping plate (104) is connected and fixed to the side plate (101) of the clamp. The clamping plate (104) has a boss with a threaded hole. The double-ended stud (114) is fixed to the clamping plate (104) by a threaded connection at one end and a wing nut (110) is screwed on the other end. The clamping block (111) is fitted onto the double-ended stud (114). One side of the clamping block (111) is an inclined surface that mates with the rear inclined surface of the gun sight. The gun ejection port is placed on the side plate (101) of the gun clamp with its back facing away from the gun clamp. Its lateral position is determined by two rear support pins (102) and a front support pin (106). The front retaining ring (105) and the rear retaining ring (103) are installed at the gun handguard and the stock, respectively, and are fixed to the side plate (101) of the clamp by screws. The front bevel of the bullpup firearm (115) abuts against the stop bar (107), the rear bevel abuts against the clamping block (111), the rear side of the clamping block (111) abuts against the rotating handle stop bar I (1091), the degree of screwing of the wing nut (110) on the stud (114) is adjusted, the rotation angle of the rotating handle (109) is adjusted, so that the rotating handle stop bar II (1092) abuts against the rear side of the firearm grip, the front-back and up-down positions of the firearm are determined and clamped.

3. The system according to claim 2, characterized in that, The target information acquisition device (2) includes a laser rangefinder (201) and a camera module (202). The laser rangefinder (201) has rectangular grooves at the four corners of its bottom edge and is fixed to the side of the clamp side plate (101) by screws.

4. The system according to claim 3, characterized in that, The pitch axis mechanism (3) includes a servo motor I (301), a servo motor mounting housing (302), a sleeve I (303), a circular swing arm (304), a deep groove ball bearing I (305), a bracket (306), a deep groove ball bearing II (307), an end cap I (308), a steering lever I (309), a height shaft (310), and a steering lever II (311); The lower ends of steering handle I (309) and steering handle II (311) are fixed in the middle groove on the upper side of the clamp side plate (101), and the upper ends are installed on the high and low shaft (310) through the shaft hole; The high and low shaft (310) is a hollow shaft structure. Two planes are symmetrically arranged on the side of the shaft, which fit into the two planes of the shaft holes on steering handle I (309) and steering handle II (311) to transmit torque. The elevation shaft (310) is mounted on the bracket (306) via deep groove ball bearing I (305) and deep groove ball bearing II (307). The bracket on the side of deep groove ball bearing II (307) is equipped with end cap I (308). The servo mounting housing (302) is fixed on the other side of the bracket. The sleeve I (303) is installed between the servo mounting housing (302) and the deep groove ball bearing I (305). The servo I (301) is fixed on the servo mounting housing (302). The output shaft of the servo I (301) is connected to the circular swing arm (304). The circular swing arm (304) is fixedly connected to one end of the elevation shaft (310). The servo I (301) drives the rotation of the elevation shaft (310), thereby driving the rotation of the gun clamp (1) and adjusting the gun elevation angle.

5. The system according to claim 4, characterized in that, When the high and low axes (310) angular displacement Angular displacement with support axis (408) satisfy At that time, the shape of the inner groove of the cam ensures that the motion law of the follower of the cam makes the cam stroke equal to the distance between the support shaft axis and the roller axis.

6. The system according to claim 5, characterized in that, The yaw mechanism (5) includes a servo motor III (501), a servo motor mounting plate (502), a swivel arm (503), a sleeve III (504), a deep groove ball bearing V (505), a steering shaft (506), a thrust ball bearing (507), and a housing (508). The yaw axis mechanism (5) is arranged above the pitch axis mechanism (3), and the directional axis (506) is the connecting part of the yaw axis mechanism (5) and the pitch axis mechanism (3). The lower end of the directional axis (506) is fixed to the bracket (306). The interior of the housing (508) is stepped. The steering shaft (506) is installed inside the housing (508) via a deep groove ball bearing V (505) and a thrust ball bearing (507). The servo mounting plate (502) is fixed inside the housing (508). A sleeve III (504) is installed between the servo mounting plate (502) and the housing (508). Servo III (501) is fixed on servo mounting plate (502). The output shaft of servo III (501) meshes with the internal gear on the swivel arm (503) and is connected to the direction shaft (506) through the swivel arm (503), driving the rotation of the direction shaft (506), thereby driving the movement of the pitch axis mechanism (3) and the gun clamp (1) to adjust the gun position.

7. The system according to claim 6, characterized in that, The suspension mechanism (6) includes a bolt assembly (601), a drone base plate (602), a shock-absorbing rubber ball assembly (603), and a carbon fiber plate (604). The suspension mechanism (6) is the connection mechanism between the loitering gun gimbal structure and the UAV platform. The bolt group (601) is the connecting component. The shock-absorbing rubber ball group (603) is evenly distributed on the bottom edge of the shell (508). The bottom surface of the lower rubber ball is attached to the carbon fiber plate (604), and the top surface of the upper rubber ball is attached to the UAV base plate (602). The bolt passes through the carbon fiber plate (604), the lower rubber ball, the bottom edge of the shell (508), the upper rubber ball, and the UAV base plate (602) in sequence, and is finally fixed by nuts and spring washers.

8. The system according to claim 7, characterized in that, The firing mechanism (7) includes a servo motor IV (701), a swing arm (702), and a trigger lever (703). Servo IV (701) is fixed on the side plate (101) of the clamp, and the output shaft of servo IV (701) is fixed to the swing arm (702) by screws; the trigger handle (703) is fixed on the swing arm (702), and servo IV (701) drives the trigger handle (703) to pull the trigger.

9. A ballistic correction method based on the system of claim 8, considering the target and the motion of the loitering gun, characterized in that, Includes the following steps: Step (1): Establish the geographical system O g X g Y g Z g Taking the location of the loitering gun's center of mass at time T1 as the origin, OY g Perpendicular to the local horizontal plane, pointing upwards, it is usually defined as OX. g Pointing due north, OZ g Pointing due east; Step (2): Establish the loitering gun body coordinate system OXYZ; the origin is located at the loitering gun's center of mass, the OX axis is located in the loitering gun's plane of symmetry and points towards the nose, the OY axis is located in the plane of symmetry and perpendicular to the OX axis and points towards the back of the aircraft, and the OZ conforms to the right-hand rule; Step (3): Determine the location of the loitering gun in the geographic system O based on the GPS positioning device of the loitering gun UAV platform. g X g Y g Z g Flight speed ; Step (4): Based on the flight speed of the loitering gun Determine the pitch angle of the loitering gun's flight attitude. Roll angle and yaw angle ; Step (5): The loitering gun tracks and aims at the target using color recognition via the camera module of the target information acquisition device; Step (6): Calculate the target velocity. At time T1, the relative distance between the target and the loitering gun is calculated using the laser rangefinder of the target information acquisition equipment, and the rotation angles of servo I (301) and servo III (501) are obtained at this time, thus determining the target's position vector in the body coordinate system OXYZ for the first time. At time T2, the process at time T1 is repeated to determine the target's position vector in the body coordinate system OXYZ for the second time. Based on the target's position vector in the machine's coordinate system OXYZ obtained at times T1 and T2, combined with the geographic coordinate system O where the loitering gun's center of mass is located at times T1 and T2... g X g Y g Z g The location of the target in the geographic system O is calculated. g X g Y g Z g Speed ​​of movement ; Step (7): Determine the response time of the loitering gun; Based on the motion law of the center of mass of the projectile in the air ballistics, the target position vector measured at time T2 is used as the ballistic parameter to determine the flight time of the projectile from the loitering gun firing and hitting the target, and then determine the total time Δt from the loitering gun from the firing command to the gimbal movement, and finally the time Δt of the projectile fired by the loitering gun to reach the target position, which is the response time of the loitering gun. Step (8): Based on the loitering gun's movement speed obtained in step (3) The target's velocity obtained in step (6) Using the response time Δt of the loitering gun obtained in step (7), calculate and determine the target and the loitering gun's position in the geographic system O at time T2+Δt. g X g Y g Z g relative position ; Step (9): Based on the flight speed of the loitering gun obtained in step (3) Adjusting the barrel axis yaw angle corrects the initial velocity direction of the projectile, ensuring that the initial velocity direction lies within the vertical plane connecting the target and the muzzle, thus obtaining the projectile's initial velocity. and yaw angle ; 、 Step (10): Based on the target and loitering gun at time T2+Δt obtained in step (8), in the geographic system O g X g Y g Z g relative position The initial velocity of the projectile obtained in step (9) Based on the motion law of the projectile's center of mass in air ballistics, the projectile launch angle is obtained. ; Step (11): Based on the pitch angle obtained in step (4) Roll angle and yaw angle The initial velocity of the projectile obtained in step (9) is... Yaw angle and the projectile launch angle obtained in step (10) The rotation angle of the elevation axis (310) in the loitering gun gimbal pitch axis mechanism from time T2 to time T2+Δt is obtained. The rotation angle of the yaw axis mechanism and the direction axis (506) .

Images