CN111874212A

CN111874212A - Practical stall passing v-tail inclination angle self-adaptive control method

Info

Publication number: CN111874212A
Application number: CN202010784163.9A
Authority: CN
Inventors: 吕永玺; 史静平; 屈晓波; 陈华坤; 谯富祥; 李卫华
Original assignee: Northwestern Polytechnical University
Current assignee: Northwestern Polytechnical University
Priority date: 2020-08-06
Filing date: 2020-08-06
Publication date: 2020-11-03
Anticipated expiration: 2040-08-06
Also published as: CN111874212B

Abstract

The invention provides a practical adaptive control method for a stall passing v-tail roll angle, which belongs to the field of aircraft control and comprises the following steps: carrying out autonomous take-off, landing and crosswind resistance control simulation verification on the V-tail tiltable unmanned aerial vehicle, and determining the minimum V-tail tilting angle required under different attack angles and sideslip angles; performing over-stall maneuvering simulation verification on the V-tail tiltable unmanned aerial vehicle vector drum, and determining the minimum V-tail tilting angle required under different attack angles and sideslip angles; determining the minimum V-tail inclination angle corresponding to the corresponding attack angle and the sideslip angle under different flight tasks; based on the thought of the maximum threshold and the dead zone, the logic of the V-tail inclination angle control strategy is constructed: and carrying out V-tail inclination angle simulation verification under different tasks. The control method is high in practicability and efficiency, starts from the requirements of autonomous take-off and landing and over-stall maneuvering control of the V-tail tiltable aircraft, solves the problem of self-adaptive control of the V-tail tilting angle of the V-tail tiltable aircraft, is high in efficiency and reliability, and is easy to practically apply in subsequent engineering.

Description

Practical stall passing v-tail inclination angle self-adaptive control method

Technical Field

The invention belongs to the field of aircraft control, and particularly relates to a practical adaptive control method for a stall passing v-tail dip angle.

Background

The V-tail tiltable airplane has stronger stealth performance and maneuverability, and when in emergency, the stealth performance can be enhanced by embedding the V-tail into the airplane body; when the short-distance combat battle is in battle, the V tail can be tilted to a certain angle, and the maneuvering performance is improved. When the V-tail tilting aircraft autonomously lands, cruises and performs vector roller heavy maneuver, the V-tail tilting angles of the aircraft are different in different task stages, when the aircraft encounters crosswind or performs heavy maneuver in the cross direction, the V-tail must tilt at a certain angle to enhance the stability of the transverse heading of the aircraft, and when the V-tail tilting angle in the cruises is smaller, the V-tail tilting angle is better so as to reduce the resistance in the flight process and increase the range of the aircraft. How can the vee-tailed tilt angle be controlled according to different tasks? Simulation analysis shows that when the sideslip angle of the aircraft for executing a task is large, the inclination angle of the V tail is necessarily large, and when the aircraft flies flatly or only does longitudinal maneuver, the flight requirement can be met by the inclination of the V tail at a small angle. In summary, for controlling the V-tailed inclination angle, the most important is to control according to the magnitude of the sideslip angle, and secondly, when the aircraft incidence angle is too large, the stability of the aircraft in the lateral direction is deteriorated, so that the control of the V-tailed inclination angle can be realized through the magnitudes of the sideslip angle and the incidence angle.

At present, the control of the tail tilting angle of the stall V can refer to the control of the sweep angle of the variable sweep wing aircraft because the research on the tail tilting aircraft is less, but the practicability of the existing variant control technology is poor. The invention aims to adaptively obtain a V-tail inclination angle under different tasks and seek a practical and efficient control strategy of the over-stall V-tail inclination angle for the V-tail inclinable unmanned aerial vehicle.

However, when the airplane flies over stall, how to automatically deflect the V-tail inclination angle to complete the flying task under different flying conditions is difficult. Therefore, the invention provides a v-tail roll angle over-stall self-adaptive control method.

Disclosure of Invention

In order to overcome the defects in the prior art, the invention provides a practical over-stall V-tail inclination angle self-adaptive control method, and solves the problem of over-stall self-adaptive deflection of the V-tail inclination angle of the airplane.

In order to achieve the above purpose, the invention provides the following technical scheme:

a practical stall v-tail roll angle self-adaptive control method comprises the following steps:

step 1, carrying out autonomous take-off, landing and crosswind resistance control simulation verification on a V-tail tiltable unmanned aerial vehicle, and determining a minimum V-tail tilting angle required under different attack angles and sideslip angles;

step 2, carrying out the passing stall maneuver simulation verification of the vector drum of the V-tail tiltable unmanned aerial vehicle, and determining the minimum V-tail tilting angle required under different attack angles and sideslip angles;

step 3, combining the step 1 and the step 2, determining the minimum V-tail inclination angle corresponding to the corresponding attack angle and sideslip angle under different flight missions;

and 4, constructing the logic of the V-tail inclination angle control method based on the maximum threshold and the thought of the dead zone:

and 5, carrying out V-tail inclination angle simulation verification under different tasks.

Preferably, the control logic of step 4 is as follows:

when the sideslip angle is larger than a certain set threshold value, the V-tail inclination angle does not perform interpolation according to the actual sideslip angle, but performs interpolation according to the current maximum sideslip angle until the sideslip angle is reduced to a given range;

for the sideslip angle, when the absolute value of the sideslip angle is smaller than a certain threshold value, the output of a logic module is set to be 0, and at the moment, the V-tail inclination angle performs interpolation according to the actual sideslip angle;

when the sideslip angle is larger than the threshold value, the output of the logic module is set to be 1, and the V tail inclination angle is interpolated according to the current maximum sideslip angle value until the sideslip angle is reduced to a given value.

The practical adaptive control method for the over-stall v-tail inclination angle provided by the invention has the following beneficial effects:

(1) the method comprises the relations among the sideslip angle, the attack angle and the V-shaped tail inclination angle, and the judgment logic is added to avoid the oscillation phenomenon of the V-shaped tail inclination angle, so that the control of the V-shaped tail inclination angle is realized theoretically, and the method is easy to realize in engineering and has strong engineering application value;

(2) the method has strong practicability and high efficiency, and lays a technical foundation for later control of the over-stall maneuver of the V-tail tiltable aircraft;

(3) the method starts from the maneuvering control requirements of the autonomous take-off and landing and over-stall of the V-tail tiltable aircraft, solves the self-adaptive control problem of the V-tail tilting angle of the V-tail tiltable aircraft, has high efficiency and strong reliability, and is easy to be practically applied in subsequent engineering.

Drawings

Fig. 1 is a V-tail tiltable unmanned aerial vehicle according to embodiment 1 of the present invention; FIG. 1(a) is a view of the trailing edge of a V-tail embedded wing in a penetration stage; FIG. 1(b) is a V-tail tilting diagram in the fighting stage;

FIG. 2 is a schematic diagram of a V-tailed roll angle control method using a stall V-tailed roll angle adaptive control method according to embodiment 1 of the present invention;

FIG. 3 is a schematic diagram of the V-tailed roll angle control logic of the adaptive stall V-tailed roll angle control method according to embodiment 1 of the present invention;

FIG. 4 is a curve of altitude and yaw of the UAV;

FIG. 5 is a plot of unmanned aerial vehicle speed, two airflow angles;

FIG. 6 is an unmanned aerial vehicle attitude angle curve;

FIG. 7 is a deflection curve of an aerodynamic control surface of the UAV;

FIG. 8 is a UAV tailtrim angle curve;

fig. 9 is a plot of drone altitude, yaw (smaller angle of attack);

FIG. 10 is a plot of velocity, two airflow angles (smaller angle of attack);

fig. 11 is an unmanned aerial vehicle attitude angle curve (smaller angle of attack);

fig. 12 is a curve of the aerodynamic control surface deflection (smaller angle of attack) of the unmanned aerial vehicle;

fig. 13 is a vector spout deflection curve (smaller angle of attack) for an unmanned aerial vehicle;

fig. 14 is a drone V-tailed cant angle curve (smaller angle of attack);

fig. 15 is a plot of drone altitude, yaw (greater angle of attack);

figure 16 is a plot of drone speed and two airflow angles (greater angle of attack);

fig. 17 is an unmanned aerial vehicle attitude angle curve (larger angle of attack);

fig. 18 is a curve of the aerodynamic control surface deflection (larger angle of attack) of the drone;

fig. 19 is a vector spout deflection curve (larger angle of attack) for an unmanned aerial vehicle;

fig. 20 is a drone V-tailed cant angle curve (larger angle of attack).

Detailed Description

In order that those skilled in the art will better understand the technical solutions of the present invention and can practice the same, the present invention will be described in detail with reference to the accompanying drawings and specific examples. The following examples are only for illustrating the technical solutions of the present invention more clearly, and the protection scope of the present invention is not limited thereby.

Example 1

The invention provides a practical adaptive control method for a stall passing V-tail tilting angle, and as shown in fig. 1, a V-tail tilting unmanned aerial vehicle in embodiment 1 of the invention is provided; FIG. 1(a) is a view of the trailing edge of a V-tail embedded wing in a penetration stage; FIG. 1(b) is a V-tail tilting diagram in the fighting stage; the control method is specifically shown in fig. 2 to 3, and includes the following steps:

and 4, constructing the logic of the V-tail inclination angle control strategy based on the maximum threshold and the thought of the dead zone:

In the specific embodiment, in order to prevent the V-tailed tilt angle oscillation phenomenon caused by the side slip angle oscillation, a logic determination loop as shown in fig. 3 is introduced, and the control logic of step 4 is as follows:

when the sideslip angle is larger than the threshold value, the output of the logic module is set to be 1, and the V tail inclination angle is interpolated according to the current maximum sideslip angle value until the sideslip angle is reduced to a given value. Therefore, the method for controlling the V-shaped tail inclination angle not only comprises the relation among the sideslip angle, the attack angle and the V-shaped tail inclination angle, but also adds the judgment logic to avoid the oscillation phenomenon of the V-shaped tail inclination angle, so that the control of the V-shaped tail inclination angle is realized theoretically, and the method is easy to realize in engineering and has high engineering application value.

According to the V tail control strategy of the V tail tiltable aircraft, crosswind, vector roller maneuver and the like are simulated in the horizontal flight process, the relation between the attack angle and the sideslip angle of the vector roller maneuver and the V tail tilt angle is obtained through simulation, and as shown in table 1, the specific simulation result is as follows.

TABLE 1V taildip angle interpolation table

Sudden crosswind simulation

Since crosswind mainly affects the lateral movement of the airplane, the lateral simulation results are similar in the independent landing and level flight phases of the V-tail tiltable airplane, and only the longitudinal simulation results are different. The situation that the side wind suddenly occurs in the process of level flight is considered, and if the V-tail inclination angle control strategy can achieve the side wind resisting capacity of the airplane, the capacity can be achieved in the process of autonomous take-off and landing.

Given the plane flight state, the altitude H is 3000m, the speed V is 110m/s, and assuming that 10s has sudden crosswind during the plane flight, the final control result of the aircraft and the V-tail tilt angle and the deflection angle of the aerodynamic control surface are as shown in fig. 4 to 8, and two different situations that the V-tail tilt angle is fixed and the V-tail tilt angle can be controlled are compared.

From the simulation results of fig. 4 to 8, it can be seen that in the case of a sudden crosswind, the same control result is obtained in both the case where the V-tailed tilt angle is fixed and the case where the V-tailed tilt angle is controllable, and the change of each state is not very different. However, as can be seen from the comparison of the V-tail inclination angle, the same control effect can resist the interference of the crosswind if the V-tail is fixed, but the V-tail is always inclined at 30 °, and the V-tail inclination angle obtained by the control strategy is stabilized at about 7 ° when no crosswind exists, and when there is crosswind, the maximum inclination angle is about 20 °, and finally returns to the flat flight value. Compared with the two conditions, the aircraft drag can be obviously reduced under the condition that the V tail can be inclined, the V tail inclination angle can deflect according to the actual state of the aircraft, and the controllability is strong.

Vector cylinder emulation

For the vector roller action, the control results of two vector rollers under a small attack angle and a large attack angle are given by switching in from a flat flying state, and compared with the case that the V tail inclination angle is fixed, the specific results are shown in FIGS. 9 to 20:

as can be seen from the simulation results of fig. 9 to 20, the same control results were obtained for both the small attack angle and the large attack angle in the cutting vector drum operation, and the change in each state was not so large. However, as can be seen from the comparison of the vee tail tilt angle, the same control effect can be obtained if the vee tail is fixed, the vector roller motion can be completed, but the vee tail is always tilted at the fixed vee tail tilt angle, and the vee tail tilt angle obtained by the control strategy is gradually changed from the tilt angle during the level flight when the vector roller motion is entered from the level flight state, and finally enters the steady state. Compared with the two conditions, the aircraft drag can be obviously reduced under the condition that the V tail can be inclined, the V tail inclination angle can deflect according to the actual state of the aircraft, and the controllability is strong.

In the embodiment, a relation table of an attack angle and a sideslip angle of the vector roller during maneuvering and a V-shaped tail inclination angle is obtained through simulation; in order to prevent oscillation of the V-tail inclination angle, a sideslip angle logic judgment strategy is provided, the strategy not only contains the relation among the sideslip angle, the attack angle and the V-tail inclination angle, but also is added with judgment logic to avoid oscillation of the V-tail inclination angle, control of the V-tail inclination angle is realized theoretically, and the method is easy to realize in engineering and has high engineering application value.

The above-mentioned embodiments are only preferred embodiments of the present invention, and the scope of the present invention is not limited thereto, and any simple modifications or equivalent substitutions of the technical solutions that can be obviously obtained by those skilled in the art within the technical scope of the present invention are included in the scope of the present invention.

Claims

1. A practical stall v-tail roll angle self-adaptive control method is characterized by comprising the following steps:

and 5, carrying out simulation verification on the V-tail inclination angles under different tasks to obtain the optimal V-tail inclination angle.

2. The practical stall vtail roll angle adaptive control method according to claim 1, wherein the control logic of step 4 is as follows: