Lateral spoiler and high-precision formation speed control method with spoiler feedback

Abstract

The present invention provides a lateral spoiler and a high-precision formation speed control method with spoiler feedback, which belongs to the technical field of unmanned aerial vehicles. The lateral spoiler includes a spoiler body, a fixing seat, a connecting line, a steering gear, a connecting rod, a connecting shaft, a connecting plate, a fixing hole, and a box body, which is connected to the control system and GPS module of the unmanned aerial vehicle. The method gives a throttle command and a deflection size of the spoiler according to the engine thrust characteristics of the unmanned aerial vehicle and the deceleration capability of the spoiler, and improves the speed response time by the rudder surface feedback mode of the spoiler. The present invention can change the opening and closing angle of the spoiler on the surface of the body with the twisting of the steering gear by installing a tilt steering gear in the box body, thereby effectively generating different stroke ratios when the unmanned aerial vehicles with a large aspect ratio fly in formation. Under different stroke ratios, the control twisting angle of the steering gear of its control system is also different, which greatly optimizes the adaptability of the aspect ratio unmanned aerial vehicle to the formation speed control accuracy.

Description

Technical Field

[0001] The invention belongs to the technical field of unmanned aerial vehicles, and in particular relates to a lateral spoiler and a high-precision formation speed control method with spoiler feedback. Background Art

[0002] Distributed multi-station interferometry SAR refers to an interferometry SAR system in which the transmitting and receiving antennas are distributed on multiple different aviation platforms. In interferometric measurement applications, compared with the re-orbit interferometry of multiple single-station SAR, distributed multi-station interferometry SAR can avoid time decoherence to improve interferometry accuracy; compared with the interferometry of single-station multi-antenna, multi-station interferometry SAR can achieve a long baseline that is difficult to obtain, thereby improving the accuracy of elevation measurement.

[0003] Distributed multi-station interferometric SAR formations include horizontal parallel flight, 45° oblique parallel flight, quadrilateral parallel flight, etc., requiring the multi-aircraft formation to have a cross-track baseline accuracy better than 3 meters, a baseline accuracy better than 10 meters, and a baseline length of 20 to 50 meters for cross-track interference of adjacent aircraft. In order to achieve the three-dimensional imaging capability of multi-baseline interferometric SAR, formation drones are required to achieve high-precision spatial synchronization along the cross-track and along-track directions of flight. At present, the longitudinal position accuracy of drone formations is mainly determined by the speed tracking characteristics. The speed control channel of fixed-wing drones controlled by engines has the characteristics of long period and low bandwidth.

[0004] Distributed multi-base SAR is installed on different fixed-wing UAVs for formation flight to achieve multi-baseline interferometric SAR three-dimensional imaging capabilities, which requires the formation UAVs to achieve high-precision spatial synchronization along the cross-track and along-track directions. When low-speed fixed-wing UAVs are flying in formation, the longitudinal position is accelerated or decelerated by adjusting the throttle of the motor. However, this speed control method that does not change the aerodynamic shape is slow to adjust and the adjustment accuracy is not high, and it cannot meet the requirements of formation spatial synchronization. Therefore, there is an urgent need for a means to actively change the shape of the UAV to produce a significant deceleration capability. In addition, the existing spoilers mainly work when the UAV is landing and have not yet been used for flight formation control. There is also no mode of coordinated speed control of the throttle and spoiler in the existing technology. Summary of the invention

[0005] In order to solve the above technical problems, the present invention provides a lateral spoiler and a high-precision formation speed control method with spoiler feedback, wherein the lateral spoiler includes a spoiler body, a fixing seat, a connecting line, a steering gear, a connecting rod, a connecting shaft, a connecting plate, a fixing hole, and a box body, which are connected to the control system and GPS module of the unmanned aerial vehicle. The method gives a throttle command and a spoiler deflection size according to the engine thrust characteristics of the unmanned aerial vehicle and the deceleration capability of the spoiler, and improves the speed response time by the rudder surface feedback method of the spoiler.

[0006] In order to achieve the above object, the present invention adopts the following technical solution:

[0007] A transverse spoiler comprises a spoiler body, a fixing seat, a connecting line, a steering gear, a first connecting rod, a first connecting shaft, a second connecting rod, a connecting plate, a box body, and a second connecting shaft; wherein the first connecting rod and the second connecting rod are connected via the first connecting shaft; the second connecting rod is connected to the spoiler body via the connecting plate; the first connecting rod is connected to the steering gear and is powered by the steering gear; the connecting line is connected to the steering gear and connects the steering gear to a battery and a single-chip microcomputer to provide signals and electrical energy to the steering gear; the steering gear, the first connecting rod, the first connecting shaft, the second connecting rod and the connecting plate are installed inside the box body; the spoiler body is connected to the fixing seat via the second connecting shaft; the transverse spoiler changes its opening and closing angle as the steering gear is twisted.

[0008] The present invention also provides a high-precision formation speed control method with spoiler feedback, which adopts a proportional-integral control method to control the speed of the UAV, converts the speed deviation signal of the UAV's target speed and current flight speed into an acceleration command of the UAV, and then gives the engine's throttle command and the size of the spoiler deflection according to the engine thrust characteristics and the deceleration capability of the lateral spoiler. By simultaneously adjusting the engine's throttle command and the size of the spoiler deflection, high-precision formation speed control is achieved.

[0009] Beneficial effects:

[0010] 1. The present invention installs a tilting servo in the box body, so that the spoiler on the surface of the body can change the opening and closing angle as the servo twists, thereby achieving the goal of effectively reducing the stroke ratio during landing when the UAV with a large aspect ratio descends. Under different stroke ratios, the control twisting angle of the control system servo is also different, which greatly optimizes the adaptability of the aspect ratio UAV to the landing environment.

[0011] 2. The present invention provides a high-precision formation speed control method with spoiler feedback, which converts the difference between the target speed and the current flight speed into an acceleration command, and then gives a throttle command and a dual deceleration mode of spoiler deflection size according to the engine thrust characteristics of the UAV and the spoiler deceleration capability. The high-precision formation control method with spoiler feedforward can quickly adjust the speed size through the feedforward method or the combination of the throttle and the spoiler, thereby improving the formation position control capability. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 It is the position installation diagram of the lateral spoiler of the present invention;

[0013] Figure 2 This is an open diagram of the lateral spoiler in front view;

[0014] Figure 3 The open diagram of the lateral spoiler in side view;

[0015] Figure 4 is a closed diagram of the lateral spoiler in front view;

[0016] Figure 5 This is the formation control framework diagram;

[0017] Figure 6 This is the speed control framework diagram.

[0018] Among them, the figure markings are: spoiler body 1, fixing seat 2, connecting line 3, servo 4, first connecting rod 5, first connecting shaft 6, second connecting rod 7, connecting plate 8, first fixing hole 9, box body 10, second fixing hole 11, third fixing hole 12, screw 13, fourth fixing hole 14, first slot hole 15, second slot hole 16, second connecting shaft 17. DETAILED DESCRIPTION

[0019] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention. In addition, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0020] The present invention provides a lateral spoiler and a high-precision formation speed control method with spoiler feedback, which controls multi-aircraft formation flight by controlling the speed of the spoiler based on the lateral freedom of the fuselage.

[0021] like Figure 1-Figure 4 As shown, the lateral spoiler of the present invention is a spoiler based on the lateral freedom of the fuselage, and comprises a spoiler body 1 , a steering gear 4 , a first connecting rod 5 , a second connecting rod 7 and a fixing seat 2 .

[0022] The spoiler body 1 is composed of two triangular ribs and a plane, which bears the air resistance during deceleration and is the core component of the lateral spoiler. The steering gear 4 performs the opening and closing actions of the spoiler body 1. The first connecting rod 5 and the second connecting rod 7 connect the steering gear 4 with the spoiler body 1, and the action of the steering gear 4 is reflected on the spoiler body 1. The fixing seat 2 is a cube with one side open, and a box body 10 is formed inside, which is used to store the steering gear 4 and the first connecting rod 5 and the second connecting rod 7. The first connecting rod 5 and the second connecting rod 7 are connected by the first connecting shaft 6. The second connecting rod 7 is fixedly connected to the spoiler body 1 through the connecting plate 8. The connecting line 3 is connected to the steering gear 4, connecting the steering gear 4 to the battery and the single-chip microcomputer, and providing signals and electrical energy to the steering gear 4; the steering gear 4, the first connecting rod 5, the first connecting shaft 6, the second connecting rod 7 and the connecting plate 8 are installed together inside the box body 10. The spoiler body 1 is engaged with the first slot 15 and the second slot 16 when in a closed state. The first slot hole 15 and the second slot hole 16 are arranged on a bracket inside the box body 10 .

[0023] Preferably, the first connecting rod 5 and the second connecting rod 7 are made of metal material, which has high hardness and can withstand greater resistance.

[0024] Preferably, the steering gear 4 is fixed in the box body 10 of the fixing seat 2 by screws 13, and the steering gear 4 has a shaft body, and the shaft body is inserted into the hole of the first connecting rod 5. The spoiler body 1 and the fixing seat 2 form a hinge structure through the second connecting shaft 17 to improve flexibility.

[0025] Preferably, the fixing base 2 is installed on the fuselage through the first fixing holes 9, the second fixing holes 11, the third fixing holes 12, the fourth fixing holes 14 on the surrounding area and two fixing holes at the center of the edge of the fixing base 2, so as to increase the force-bearing area and strengthen it.

[0026] Preferably, the spoiler body 1 and the fixing seat 2 are made of metal materials to bear greater resistance.

[0027] The steering engine 4 is connected to the control system and GPS module of the UAV.

[0028] The spoiler body 1 adopts an adjustable structure so as to be adjusted according to different flight conditions and work requirements. The main material of the lateral spoiler is a lightweight, high-strength composite material, such as a carbon fiber composite material. The lateral spoiler is installed on the side of the fuselage, etc. The number and layout of the spoilers are determined according to the size and flight performance requirements of the UAV.

[0029] According to the flight performance and aerodynamic characteristics of the UAV, the adjustment range, adjustment speed and other parameters of the spoiler body 1 are set. At different flight speeds, the spoiler body 1 can be adjusted to open at different angles to facilitate the control of the UAV. During the actual flight process, the state of the UAV can be monitored in real time through sensors, and the lateral spoilers can be adjusted as needed.

[0030] like Figure 5 As shown, the large fixed-wing UAV formation control system of the present invention includes an inter-machine communication module, a collaborative path point following control module, a collaborative formation module, and a stabilization loop control module.

[0031] The inter-machine communication module is responsible for the information exchange between the leader and all wingmen in the link, providing data support for collaborative control. Due to the limitation of the hardware communication bandwidth, the amount of interactive communication data must be controlled in actual use, and only the necessary collaborative information interaction is retained to obtain collaborative variables, so as to ensure that a larger-scale formation flight can be carried out without changing the total communication bandwidth.

[0032] The collaborative path point following control module is the core of the entire large fixed-wing UAV formation control system. Its main function is to guide the wingman in the formation to the desired path point through formation management (i.e. collaborative formation), and to achieve collaborative control using the interactive information provided by the inter-machine communication module. The collaborative path point following control module can serve as the guidance loop of the UAV, and the output desired heading, desired altitude, and desired speed instructions can serve as input information for the stabilization loop.

[0033] The collaborative formation module includes a formation management module and an expected path point calculation module. The formation management module contains a variety of pre-designed formation libraries, which can be switched according to task instructions and can reconstruct the formation when an unexpected situation occurs. The expected path point calculation module calculates the position offset of the formation library in the formation management module to obtain the collaborative path point of each drone relative to the leader's position.

[0034] The stabilization loop control module includes an attitude loop, an angular velocity loop, and an actuator composed of a motor and a servo. The stabilization loop control module uses the output of the collaborative path point following control module to generate execution instructions for the motor and the servo, thereby achieving control of the attitude, speed, and altitude of the drone.

[0035] The large fixed-wing UAV formation control system uses a single-chip microcomputer to realize real-time monitoring and adjustment of the lateral spoiler, and has the following functions:

[0036] 1. Receive instructions from the flight controller or pilot to achieve automatic or manual adjustment of the lateral spoiler.

[0037] 2. Collect sensor data in real time, analyze the status of the drone, and automatically adjust the lateral spoilers as needed.

[0038] 3. It has fault diagnosis and protection functions to ensure the safe operation of the lateral spoiler.

[0039] When the lateral spoiler needs to be regulated, the control system transmits the command to the steering gear 4 through the connecting line 3, and the steering gear 4 provides torque, which is transmitted to the spoiler body 1 through the first connecting rod 5 and the second connecting rod 7, driving the opening and closing of the spoiler body 1. In different environments, the control system makes different commands, and the opening angle and closing angle of the spoiler body 1 are also different, which can be suitable for decelerating the drone at different flight speeds.

[0040] like Figure 6 As shown, the present invention also provides a high-precision formation speed control method with spoiler feedback, which uses a proportional integral (PI) control method to control the speed of the UAV, inputs the speed deviation between the target speed of the UAV and the current flight speed into the PI controller and converts it into an acceleration command, performs control distribution, and then gives the engine throttle command and the size of the spoiler deflection according to the engine thrust characteristics of the UAV and the deceleration capability of the lateral spoiler, so as to achieve high-precision formation speed control, including:

[0041] First, the response of the speed channel to the speed command is regarded as a second-order system. The model of the given speed command is as follows:

[0042] (1)

[0043] in, is the flight speed, is the flight speed instruction, is the transfer function identifier, is the natural frequency of the model for the velocity command.

[0044] The transient and steady-state characteristics of the speed command model are determined by the damping ratio of the speed command model. The natural frequency of the model with the speed command Decide.

[0045] Speed ​​deviation signal for:

[0046] (2)

[0047] Generally speaking, the speed adjustment is much slower than the execution frequency of the system, so the speed command can be considered to be a constant in the two control cycles before and after. Then the second-order derivative of the flight speed command is and the first derivative of the flight speed command 0, establish speed deviation signal The state equation is:

[0048] (3)

[0049] in, Is the speed deviation signal The second-order derivative of Is the speed deviation signal The first derivative of ;

[0050] Substituting formula (2) into formula (3) yields:

[0051] (4)

[0052] in, is the acceleration command, Flight speed The second derivative of

[0053] Integrate and shift the above formula to get the acceleration command As shown below:

[0054] (5)

[0055] Where t is time.

[0056] The parameters for specifying the PI control method are:

[0057] (6)

[0058] in, , They are proportional gain and integral gain respectively;

[0059] The acceleration command is calculated by formula (5): Finally, combined with the UAV's engine thrust model, the engine throttle command and the size of the spoiler deflection are given according to the UAV's engine thrust characteristics and the spoiler's deceleration capability.

[0060] Through the above technical solutions, the lateral spoilers on the fuselage can effectively improve the aerodynamic performance of the drone, and enhance flight stability, controllability and safety. At the same time, the adjustment function of the spoilers enables it to adapt to different flight conditions, effectively improving the safety performance of the drone.

Claims

1. A high-precision formation speed control method with spoiler feedback, characterized in that: The speed of the UAV is controlled by proportional-integral control. The speed deviation signal between the target speed and the current flight speed of the UAV is converted into the acceleration command of the UAV. Then, the throttle command of the engine and the deflection size of the spoiler are given according to the thrust characteristics of the engine and the deceleration capability of the lateral spoiler. By adjusting the throttle command of the engine and the deflection size of the spoiler at the same time, high-precision formation speed control is achieved together. The model for a given speed command is as follows: （1） in, is the flight speed, is the flight speed instruction, is the transfer function identifier, is the natural frequency of the model of the speed command; The transient and steady-state characteristics of the speed command model are determined by the damping ratio of the speed command model. The natural frequency of the model with the speed command Decide; Speed ​​deviation signal for: （2） Consider the second derivative of the flight speed command and the first derivative of the flight speed command 0, establish speed deviation signal The state equation is: （3） in, Is the speed deviation signal The second-order derivative of Is the speed deviation signal The first derivative of ; Substituting formula (2) into formula (3) yields: （4） in, is the acceleration command, Flight speed The second derivative of Integrate and shift the above formula to get the acceleration command : （5） Where, t is time; The parameters for specifying the proportional-integral control method are: （6） in, , They are proportional gain and integral gain respectively; The acceleration command is calculated by formula (5): Finally, combined with the UAV's engine thrust model, the engine throttle command and the size of the spoiler deflection are given according to the UAV's engine thrust characteristics and the deceleration capability of the lateral spoiler.

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