CN114740874A - Unmanned aerial vehicle rocket boosting launching rolling attitude control method - Google Patents

Abstract

The invention relates to a method for controlling the rolling attitude of the rocket booster launch of an unmanned aerial vehicle. The UAV rocket-assisted launch roll attitude control method includes: using a flight control computer to collect the roll angle rate, yaw angle rate, roll angle and flight speed of the UAV; The rotation angle, flight speed, the set roll angle control command and the reference speed command are input into the lateral heading control system, and the flight control computer is used to calculate the real-time control law, and the control amount of the aileron rudder surface deflection angle and the rudder surface deflection angle control are obtained. According to the control amount of the deflection angle of the aileron rudder surface and the deflection angle of the rudder rudder surface, the aileron servo and the rudder servo are respectively driven to adjust the roll attitude of the UAV. The control method of the present application can realize the stable control of the roll attitude during the launch of the UAV, so as to realize the safe launch of the UAV.

Description

Rolling attitude control method for UAV rocket booster launch

technical field

The present application relates to the technical field of UAV control, in particular, to a method for controlling the roll attitude of UAV rocket-assisted launch.

Background technique

At present, UAVs have been widely used in military and civilian fields. Rocket-assisted zero-length launch is a common UAV launch method. This launch method is not restricted by the take-off site, and has strong maneuverability, which expands the use range of the UAV. The rocket-assisted launch process is a key link in the UAV flight process and plays a decisive role in safe flight. During the zero-length launch, the rotation of the propeller will generate a moment opposite to the direction of rotation, that is, the propeller anti-torque. The propeller anti-torque will affect the roll attitude of the drone in the early stage of launch. Excessive anti-torque will cause the roll angle of the drone to be too large during the launch process, resulting in the drone falling high, the wing tip touching the ground or even the launch failure. risks of. The traditional non-dynamic pressure correction control strategy cannot achieve a good suppression effect on the roll angle at the low speed in the early stage of launch.

SUMMARY OF THE INVENTION

In order to reduce the influence of the propeller anti-torque on the rolling attitude during the launch process of the rocket-assisted zero-length launch UAV, the main purpose of this application is to provide a kind of UAV rocket-assisted launch roll The attitude control method can realize the stable control of the roll attitude during the launch of the UAV, so as to realize the safe launch of the UAV.

In order to achieve the above purpose, the present application provides a method for controlling the roll attitude of a UAV rocket booster launch, including:

Step S1: use the flight control computer to collect the roll angle rate, yaw angle rate, roll angle and flight speed of the drone;

Step S2: Input the roll angle rate, yaw angle rate, roll angle, flight speed, set roll angle control command and reference speed command into the lateral heading control system, and use the flight control computer to calculate the real-time control law to obtain the auxiliary The control amount of the deflection angle of the wing rudder surface and the control amount of the deflection angle of the rudder rudder surface;

Step S3: according to the control amount of the deflection angle of the aileron rudder surface and the control amount of the deflection angle of the rudder rudder surface, respectively drive the aileron servo and the rudder servo to move, so as to adjust the roll attitude of the UAV.

Further, in the step S2, the control law solution formula for the control amount of the rudder surface deflection angle is:

Δδ _r =K _r r

Among them: Δδ _r is the rudder surface deflection angle control amount; K _r is the yaw angle rate amplification factor; r is the yaw angle rate.

Further, in the step S2, if the flight speed is less than the reference speed, the control law calculation formula of the control amount of the aileron rudder surface deflection angle is:

Among them, Δδ _a is the control amount of the aileron rudder surface deflection angle; K _p is the roll angle rate amplification coefficient; K _φ is the roll angle amplification coefficient; K _φi is the roll angle integral control coefficient; p is the roll angle rate; V is the flight speed ; V _ref is the reference speed; φ is the roll angle; φ _g is the roll angle command; Δφ is the roll angle deviation.

Further, K _r , K _p , K _φ and K _φi are obtained through control law design and simulation.

Further, the steps of control law design and simulation include:

According to the time-domain analysis and frequency-domain analysis of the linearized simulation, the selection range of the control coefficients that meet the performance requirements is obtained;

The simulation time domain analysis is carried out using the 6-DOF nonlinear model, and K _r , K _p , K _φ and K _φi are obtained.

Further, in the step S2, if the flight speed is greater than or equal to the reference speed, the control law solution formula for the control amount of the aileron rudder surface deflection angle is:

Δδ _a =K _p p+K _φ (φ-φ _g )+K _φi ∫(φ-φ _g )dtΔφ=φ-φ _g

Among them, Δδ _a is the control amount of the aileron rudder surface deflection angle; K _p is the roll angle rate amplification coefficient; K _φ is the roll angle amplification coefficient; K _φi is the roll angle integral control coefficient; p is the roll angle rate; V is the flight speed ;φ is the roll angle; φ _g is the roll angle command; Δφ is the roll angle deviation.

Further, in the step S1, the roll angular rate and the yaw angular rate of the UAV are obtained by using the angle rate gyro measurement.

Further, in the step S1, the roll angle of the unmanned aerial vehicle is obtained by using the attitude system to measure.

Further, in the step S1, the flight speed of the UAV is obtained by measuring the airspeed sensor.

Further, both the aileron steering gear and the rudder steering gear are servo steering gears.

Applying the technical solution of the present application, the UAV rocket-assisted launch roll attitude control method can use the dynamic pressure correction strategy to effectively control the servo rudder surface under the condition of low dynamic pressure during the zero-length launch process, and realize the roll during the launch process. Attitude stability control, so as to achieve safe launch.

Description of drawings

The drawings are for the purpose of illustrating specific embodiments only and are not to be considered limiting of the invention, and like reference numerals refer to like parts throughout the drawings.

1 is a flow chart of a method for controlling the roll attitude of a UAV rocket booster launch disclosed in an embodiment of the present application;

Fig. 2 is the lateral course decision-making flow chart in the UAV rocket boosted launch process disclosed in the embodiment of the present application;

3 is a schematic diagram of a lateral heading control system in the process of boosting the launch of a UAV rocket disclosed in an embodiment of the present application;

FIG. 4 is a schematic diagram of the solution of the deflection angle control amount of the aileron rudder surface and the deflection angle control amount of the rudder rudder surface during the UAV rocket-assisted launching process disclosed in the embodiment of the present application.

Detailed ways

It should be noted that the embodiments in the present application and the features of the embodiments may be combined with each other in the case of no conflict. The present application will be described in detail below with reference to the accompanying drawings and in conjunction with the embodiments.

It should be noted that the terminology used herein is for the purpose of describing specific embodiments only, and is not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly dictates otherwise, the singular is intended to include the plural as well, furthermore, it is to be understood that when the terms "comprising" and/or "including" are used in this specification, it indicates that There are features, steps, operations, devices, components and/or combinations thereof.

The relative arrangement of the components and steps, the numerical expressions and numerical values set forth in these embodiments do not limit the scope of the present application unless specifically stated otherwise. Meanwhile, it should be understood that, for the convenience of description, the dimensions of various parts shown in the accompanying drawings are not drawn in an actual proportional relationship. Techniques, methods, and devices known to those of ordinary skill in the relevant art may not be discussed in detail, but where appropriate, such techniques, methods, and devices should be considered part of the authorized description. In all examples shown and discussed herein, any specific value should be construed as illustrative only and not as limiting. Accordingly, other examples of exemplary embodiments may have different values. It should be noted that like numerals and letters refer to like items in the following figures, so once an item is defined in one figure, it does not require further discussion in subsequent figures.

Referring to FIGS. 1 to 4 , according to an embodiment of the present application, a method for controlling the roll attitude of UAV rocket-assisted launch is provided, and the method for controlling the roll attitude of UAV rocket-assisted launch can be performed at zero length Under the condition of low dynamic pressure during the launch process, the dynamic pressure correction strategy is used to effectively control the servo rudder surface to achieve stable control of the roll attitude during the launch process, thereby achieving safe launch.

Specifically, the UAV rocket-assisted launch roll attitude control method of the present application is implemented by the lateral heading control system shown in FIG. 3 , and the lateral heading control system has a flight control computer, aileron steering gear, and rudder steering gear. , angular rate gyroscope, heading system and airspeed sensor. Among them, the flight control computer collects the real-time measurement information and command information of each sensor, solves it through the current control law, and outputs the control quantities of the aileron channel and rudder channel; the aileron servo and the rudder servo respectively execute the current corresponding servo motion command; angular rate gyro measurement is used to obtain the roll angle rate and yaw angle rate of the UAV at this time; the attitude system is used to measure the roll angle of the UAV at this time; the airspeed sensor is used to measure the The airspeed of the man-machine.

During the actual launch of the UAV, the rotation of the propeller during the zero-length launch of the UAV rocket will generate a torque opposite to the direction of rotation, that is, the propeller anti-torque. Due to the anti-torque of the propeller of the UAV, a large lateral roll attitude change may occur during the launch process and the UAV yaw. Excessive roll attitude will cause the risk of the drone falling high, the wing tip touching the ground or even the launch failure. Therefore, the adopted control strategy should try to control the UAV to maintain a stable attitude without excessive attitude changes.

During the launch, the rolling moment can be corrected by the deflection of the aileron rudder, and part of the reaction torque can be offset by adjusting the lateral installation angle of the rocket. When the speed at the initial stage of launch is low, and the non-dynamic pressure correction control strategy cooperates with adjusting the rocket installation angle to jointly control the lateral heading attitude, the roll attitude changes greatly, and the control effect is not ideal. Especially when the propeller absorbs a large amount of power and the rotational speed is low, it will face the problem of an increase in the magnitude of the counter torque. At this time, the combined control of adjusting the rocket installation angle and the non-dynamic pressure correction control strategy has very limited effect on suppressing the roll attitude. The present application adopts a new dynamic pressure correction control strategy, which can further suppress the roll attitude during the launch process on the basis of the above-mentioned control, so as to realize the stable control of the roll attitude during the launch process.

As shown in Figure 2, during the actual launch of the UAV, when the UAV enters the zero-length launch state, each launch command is in place, and the dynamic pressure correction control strategy of the launch section is executed. Under the action of the thrust of the rocket booster, the UAV accelerates, and the UAV's flight speed is accelerated from static to approach the set reference speed. At this time, the current UAV flight speed is determined. If the current flight speed is less than the set reference speed, then Continue to execute the dynamic pressure correction control strategy, and execute the non-dynamic pressure correction control strategy if the current flight speed is greater than the set reference speed. When the UAV booster rocket falls off, it is determined whether the speed, altitude and attitude of the UAV meet the safety conditions.

In the non-dynamic pressure correction control strategy, the control law of the aileron channel uses the roll angle control loop to increase the system damping and control the lateral attitude through the lateral heading control system. The roll angle rate, roll angle and roll angle integral are fed back to the aileron channel in the roll angle control loop. Among them, the roll angle rate feedback is used to increase the roll damping, so that the roll angle can be smoothly transitioned; the roll angle feedback is used to control the stable roll attitude; the roll angle integral feedback is used to improve the roll attitude control accuracy and eliminate the static attitude error.

环节，起到在低动压条件下进一步抑制滚转的作用，其中，V为无人机的飞行速度，V_ref为参考速度。In the dynamic pressure correction control strategy, the control law of the aileron channel is based on the above non-dynamic pressure correction control strategy, and is increased on the basis of the roll angle amplification factor and the roll angle integral control factor.

It plays the role of further suppressing the roll under the condition of low dynamic pressure, where V is the flight speed of the UAV, and _Vref is the reference speed.

In both the dynamic pressure correction control strategy and the non-dynamic pressure correction control strategy, the control law of the rudder channel increases the heading damping by feeding back the yaw rate to the rudder in the lateral heading control system.

Specifically, the UAV rocket-assisted launch roll attitude control method in the present application has three steps, namely step S1, step S2 and step S3.

Step S1: Use the flight control computer to collect the roll angle rate, yaw angle rate, roll angle and flight speed of the drone.

In this step, parameters such as roll angle, roll angle rate, yaw angle rate, and flight speed used in the lateral heading attitude control law can be measured by corresponding sensors. Specifically, the roll angle rate and yaw rate of the UAV are measured by the angle rate gyro; the roll angle of the man-machine is measured by the attitude system; the flight speed of the UAV is measured by the airspeed sensor.

Step S2: Input the roll angle rate, yaw angle rate, roll angle, flight speed, set roll angle control command and reference speed command in step S1 into the lateral heading control system, and use the flight control computer to solve the real-time control law Calculate to get the control amount of the deflection angle of the aileron rudder surface and the deflection angle of the rudder rudder surface.

If the flight speed is less than the reference speed, that is, V < V _ref , the control law solution formula for the control amount of the aileron rudder surface deflection angle is:

If the flight speed is greater than or equal to the reference speed, that is, V≥V _ref , the control law solution formula for the control amount of the aileron rudder surface deflection angle is:

Δδ _a =K _p p+K _φ (φ-φ _g )+K _φi ∫(φ-φ _g )dtΔφ=φ-φ _g

The control law solution formula for the control amount of the deflection angle of the rudder surface is:

Δδ _r =K _r r

In the above formula, Δδ _a is the aileron control amount; Δδ _r is the rudder control amount; K _p is the roll angle rate amplification factor; K _r is the yaw angle rate amplification factor; K _φ is the roll angle amplification factor; K _φi is the Roll angle integral control coefficient; p is the roll angle rate; r is the yaw angle rate; V is the speed; V _ref is the reference speed; φ is the roll angle; φ _g is the roll angle command; Δφ is the roll angle deviation. K _r , K _p , K _φ and K _φi are obtained through control law design and simulation. Specifically, the steps of control law design and simulation include: obtaining a selection range of control coefficients that meets performance requirements according to linearized simulation time domain analysis and frequency domain analysis; using a six-degree-of-freedom nonlinear model to perform simulation time domain analysis to obtain K _r , K _p , K _φ and K _φi , so as to complete the selection and optimization of control coefficients.

Step S3: according to the control amount of the deflection angle of the aileron rudder surface and the control amount of the deflection angle of the rudder rudder surface, respectively drive the aileron servo and the rudder servo to move, so as to adjust the roll attitude of the UAV.

In this step, according to the control amount of the deflection angle of the aileron rudder surface and the deflection angle of the rudder rudder surface obtained by the calculation in step S2, the corresponding servo steering gear is driven to move, so that the UAV can be moved in the shortest time. The attitude is controlled to the expected value, and the stable attitude control of the launch process is realized, and the safe launch is finally successfully achieved. Optionally, both the aileron steering gear and the rudder steering gear in this embodiment are servo steering gears, which have high control precision and good stability.

From the above description, it can be seen that the above-mentioned embodiments of the present application achieve the following technical effects: the control method can effectively control the servo rudder surface by using the dynamic pressure correction strategy under the condition of low dynamic pressure during the zero-length launch process, and realize The stable control of the roll attitude during the launch process can realize the safe launch of the UAV.

For ease of description, spatially relative terms, such as "on", "over", "on the surface", "above", etc., may be used herein to describe what is shown in the figures. The spatial positional relationship of one device or feature shown to other devices or features. It should be understood that spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, elements described as "above" or "over" other devices or features would then be oriented "below" or "over" the other devices or features under other devices or constructions". Thus, the exemplary term "above" can encompass both an orientation of "above" and "below." The device may also be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptions used herein interpreted accordingly.

In addition, it should be noted that the use of words such as "first" and "second" to define components is only for the convenience of distinguishing corresponding components. Unless otherwise stated, the above words have no special meaning and therefore cannot be understood to limit the scope of protection of this application.

The above descriptions are only preferred embodiments of the present application, and are not intended to limit the present application. For those skilled in the art, the present application may have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of this application shall be included within the protection scope of this application.

Claims (10)

1. An unmanned aerial vehicle rocket boosting launching rolling attitude control method is characterized by comprising the following steps:

step S1: collecting the roll angle rate, the yaw angle rate, the roll angle and the flight speed of the unmanned aerial vehicle by using a flight control computer;

step S2: inputting the roll angle rate, the yaw rate, the roll angle, the flight speed, the set roll angle control instruction and the reference speed instruction into a horizontal course control system, and performing real-time control law resolving by using a flight control computer to obtain the control quantity of the deflection angle of the control surface of the aileron and the control quantity of the deflection angle of the control surface of the rudder;

step S3: and respectively driving an aileron steering engine and a rudder steering engine to move according to the aileron control surface deflection angle control quantity and the rudder control surface deflection angle control quantity so as to adjust the rolling attitude of the unmanned aerial vehicle.

2. The unmanned rocket launch-assisted rolling attitude control method according to claim 1, wherein in step S2, the control law of rudder control surface deflection angle control quantity is calculated by the formula:

Δδ_r＝K_rr

wherein: delta delta_rThe control quantity of the deflection angle of the rudder surface of the rudder is obtained; k_rIs a yaw rate amplification factor; r is the yaw rate.

3. The method for controlling the roll attitude in rocket-assisted launch of unmanned aerial vehicle according to claim 2, wherein in step S2, if the flight speed is less than the reference speed, the formula for resolving the control law of the amount of flap control surface deflection angle control is:

wherein, Delta delta_aThe deflection angle control quantity of the aileron control surface is obtained; k_pRoll rate amplification factor; k_φRoll angle amplification factor; k_φiIs a roll angle integral control coefficient; p is the roll rate; v is the flying speed; v_refIs a reference speed; phi is a rolling angle; phi is a_gIs a roll angle command; and delta phi is the roll angle deviation amount.

4. The unmanned rocket-assisted launching roll attitude control method according to claim 3, wherein K is_r、K_p、K_φAnd K_φiThe method is obtained through control law design and simulation.

5. The unmanned aerial vehicle rocket assisted launching roll attitude control method according to claim 4, wherein the steps of control law design and simulation include:

obtaining a control coefficient selection range meeting performance requirements according to linearized simulation time domain analysis and frequency domain analysis;

carrying out simulation time domain analysis by utilizing a six-degree-of-freedom nonlinear model to obtain K_r、K_p、K_φAnd K_φi。

6. The unmanned rocket launch-assisted rolling attitude control method according to any one of claims 1 to 5, wherein in said step S2, if the flying speed is greater than or equal to the reference speed, the control law of the flap control plane deflection angle control quantity is calculated as:

Δδ_a＝K_pp+K_φ(φ-φ_g)+K_φi∫(φ-φ_g)dtΔφ＝φ-φ_g

wherein, Delta delta_aThe deflection angle control quantity of the aileron control surface is obtained; k is_pRoll rate amplification factor; k_φRoll angle amplification factor; k_φiIs a roll angle integral control coefficient; p is the roll rate; v is the flying speed; phi is a rolling angle; phi is a_gIs a roll angle command; and delta phi is the roll angle deviation amount.

7. The unmanned aerial vehicle rocket-assisted launching roll attitude control method according to any one of claims 1 to 5, wherein in step S1, the roll angular rate and yaw angular rate of the unmanned aerial vehicle are obtained by angular rate gyro measurement.

8. The unmanned aerial vehicle rocket-assisted launching roll attitude control method according to any one of claims 1 to 5, wherein in step S1, the roll angle of the unmanned aerial vehicle is measured by using an attitude and heading system.

9. The unmanned aerial vehicle rocket-assisted launching roll attitude control method according to any one of claims 1 to 5, wherein in step S1, the flying speed of the unmanned aerial vehicle is measured by an airspeed sensor.

10. A method for controlling rocket-assisted launch and roll attitude of an unmanned aerial vehicle according to any one of claims 1 to 5, wherein said aileron steering engine and said rudder steering engine both serve as steering engines.

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