CN113835438A - Control method for catapult take-off of unmanned aerial vehicle - Google Patents

Control method for catapult take-off of unmanned aerial vehicle Download PDF

Info

Publication number
CN113835438A
CN113835438A CN202111144317.9A CN202111144317A CN113835438A CN 113835438 A CN113835438 A CN 113835438A CN 202111144317 A CN202111144317 A CN 202111144317A CN 113835438 A CN113835438 A CN 113835438A
Authority
CN
China
Prior art keywords
unmanned aerial
aerial vehicle
control
angle
course
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
CN202111144317.9A
Other languages
Chinese (zh)
Other versions
CN113835438B (en
Inventor
王松
毛浩
骈学超
付仁皓
唐嘉鑫
吴珂帆
莫竣然
张楠
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Beijing Chong Heng Control Technology Co ltd
Beihang University
Original Assignee
Beijing Chong Heng Control Technology Co ltd
Beihang University
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Beijing Chong Heng Control Technology Co ltd, Beihang University filed Critical Beijing Chong Heng Control Technology Co ltd
Priority to CN202111144317.9A priority Critical patent/CN113835438B/en
Publication of CN113835438A publication Critical patent/CN113835438A/en
Application granted granted Critical
Publication of CN113835438B publication Critical patent/CN113835438B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • G—PHYSICS
    • G05—CONTROLLING; REGULATING
    • G05D—SYSTEMS FOR CONTROLLING OR REGULATING NON-ELECTRIC VARIABLES
    • G05D1/00—Control of position, course, altitude or attitude of land, water, air or space vehicles, e.g. using automatic pilots
    • G05D1/08—Control of attitude, i.e. control of roll, pitch, or yaw
    • G05D1/0808—Control of attitude, i.e. control of roll, pitch, or yaw specially adapted for aircraft
    • G—PHYSICS
    • G05—CONTROLLING; REGULATING
    • G05D—SYSTEMS FOR CONTROLLING OR REGULATING NON-ELECTRIC VARIABLES
    • G05D1/00—Control of position, course, altitude or attitude of land, water, air or space vehicles, e.g. using automatic pilots
    • G05D1/10—Simultaneous control of position or course in three dimensions
    • G05D1/101—Simultaneous control of position or course in three dimensions specially adapted for aircraft
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
    • Y02T10/00—Road transport of goods or passengers
    • Y02T10/10—Internal combustion engine [ICE] based vehicles
    • Y02T10/40—Engine management systems

Landscapes

  • Engineering & Computer Science (AREA)
  • Aviation & Aerospace Engineering (AREA)
  • Radar, Positioning & Navigation (AREA)
  • Remote Sensing (AREA)
  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Automation & Control Theory (AREA)
  • Control Of Position, Course, Altitude, Or Attitude Of Moving Bodies (AREA)

Abstract

The invention discloses a control method for catapult takeoff of an unmanned aerial vehicle, belonging to the field of unmanned aerial vehicle control; firstly, the unmanned aerial vehicle is powered on for standby, each control plane keeps a middle position, and takeoff parameters are initialized and set; monitoring a ground station instruction in real time, controlling the rocket to ignite after the instruction is received to enter a take-off state, and entering a take-off first stage; judging the ground speed and the airspeed of the unmanned aerial vehicle, and entering a second stage if the ground speed and the airspeed of the unmanned aerial vehicle are greater than a set threshold value and the ignition is successful; otherwise, the ignition fails, and the takeoff process is stopped. Then, judging the current height of the unmanned aerial vehicle in real time, entering a third stage after reaching the safe height, controlling the engine to linearly increase to a climbing accelerator, controlling the unmanned aerial vehicle to fly to a first waypoint of a preset mission route, and simultaneously starting longitudinal position control, course position control and course attitude control; when the GPS or the measurement and control data link is abnormal, the course, the height and the speed of the unmanned aerial vehicle are kept regulated and controlled. The invention ensures the reliability of the system and realizes the full-autonomous takeoff process.

Description

Control method for catapult take-off of unmanned aerial vehicle
Technical Field
The invention belongs to the technical field of unmanned aerial vehicle control, and particularly relates to a control method for catapult take-off of an unmanned aerial vehicle.
Background
In recent years, unmanned aerial vehicles have become more and more abundant in variety and complex in performable tasks while developing rapidly, and the unmanned aerial vehicles are more and more valued in the military industry due to the advantages of unmanned driving and low cost.
The unmanned aerial vehicle can be divided into a running takeoff mode, a hand throwing takeoff mode, an ejection takeoff mode and the like according to different takeoff modes of the unmanned aerial vehicle, and has respective advantages and disadvantages, wherein the unmanned aerial vehicle can obtain enough mechanical energy in a short time under the action of a boosting rocket during the ejection takeoff so as to reach the height and the speed of safe flight before a rocket booster falls off, and the unmanned aerial vehicle can continuously fly under the action of an engine after the rocket booster falls off. The take-off mode has good maneuverability, can take off smoothly in a more complex task environment and a take-off environment, has less limitation on the required take-off field, and can also be launched and taken off on the ground or a naval vessel, thereby having wide application prospect.
When the unmanned aerial vehicle launches and takes off, the control of taking off is important, wherein in the standby and taking-off stages before taking off, the magnetic compass of the unmanned aerial vehicle is influenced by magnetic environments such as a launching rack or a launching box, the magnetic heading precision obtained by the magnetic compass is obviously reduced and even can not be used, and after taking off, the magnetic compass still needs to be corrected for a period of time to obtain more accurate heading measurement precision. Without improving the takeoff control method, the flight safety is seriously threatened.
Disclosure of Invention
The invention provides a control method for catapult takeoff of an unmanned aerial vehicle, aiming at the defects of the prior art, and the control method is suitable for controlling one-key takeoff of the unmanned aerial vehicle by a flight control system.
The control method for the catapult takeoff of the unmanned aerial vehicle comprises a first stage of rocket ignition; in the second stage, the unmanned aerial vehicle climbs to a safe height; and a third phase of entering the first waypoint of the business route from the safe altitude;
the method comprises the following specific steps:
the method comprises the steps that firstly, an unmanned aerial vehicle A to be launched is electrified, a launcher is installed for standby, each control plane keeps a middle position, and a pitch angle, a roll angle and a course angle of catapult takeoff, a lower flight altitude limit and a preset mission air line are initialized.
Secondly, monitoring a control instruction of the ground station in real time by the unmanned aerial vehicle A, and entering a takeoff state from a ground state after receiving an effective takeoff instruction;
thirdly, a flight control system of the unmanned aerial vehicle A sends a signal to control the rocket to be ignited, the rocket and the unmanned aerial vehicle A are ejected together, and the first stage of takeoff is started;
fourthly, after the rocket is ignited, the flight control system judges the ground speed and the airspeed of the unmanned aerial vehicle A, and when the ground speed and the airspeed of the unmanned aerial vehicle A are larger than set thresholds, the rocket is ignited successfully, and the second stage is started; and if the ground speed or the airspeed is far lower than a set threshold value after the rocket is ignited for a period of time, considering that the rocket is ignited unsuccessfully, stopping the take-off process, and starting the engine to shut down the vehicle.
In the first stage and the second stage, the rudder of the unmanned aerial vehicle A maintains a middle position, and the longitudinal attitude control and the rolling attitude control are started;
the longitudinal attitude control takes an initial preset takeoff pitch angle as PID controller input, takes the current pitch angle and pitch angle speed of the unmanned aerial vehicle A as feedback, and calculates and outputs rudder amount delta of the elevatoreKeeping the unmanned aerial vehicle A at the set takeoff and climb angle;
rudder quantity delta of the output elevatoreThe calculation formula is as follows:
Figure BDA0003285125210000021
wherein ,
Figure BDA0003285125210000022
as a feedback factor of the pitch angle,
Figure BDA0003285125210000023
as an integral coefficient of the pitch angle,
Figure BDA0003285125210000024
for pitch rate feedback coefficient, theta0Is the initial set pitch angle, theta is the current pitch angle of the unmanned aerial vehicle A, q is the current pitch angle speed of the unmanned aerial vehicle A;
the roll attitude control keeps the roll angle of the unmanned aerial vehicle A at 0 degree, the target roll angle 0 degree initially set by the unmanned aerial vehicle A is used as the input of a PID controller, the current roll angle and the roll angular speed of the unmanned aerial vehicle A are used as feedback, and the rudder quantity delta of the output aileron is calculateda；
Rudder quantity delta of output aileronaThe calculation formula is as follows:
Figure BDA0003285125210000025
wherein ,
Figure BDA0003285125210000026
as a feedback coefficient of the roll angle,
Figure BDA0003285125210000027
as an integral coefficient of the roll angle,
Figure BDA0003285125210000028
as a feedback coefficient of the roll angular velocity,
Figure BDA0003285125210000029
for the roll angle to be initially set up,
Figure BDA00032851252100000210
is the current roll angle of drone a and p is the current roll angular velocity of drone a.
Step five, the flight control system judges the current height of the unmanned aerial vehicle A in real time, when the unmanned aerial vehicle A reaches the safe height, the third stage is entered, the flight control system sends a signal to control the engine to start, the engine throttle is linearly increased from the idle throttle to the climbing throttle, and the unmanned aerial vehicle A is separated from the rocket;
step six, after entering the third stage, the flight control system controls the unmanned aerial vehicle A to fly to a first waypoint of a preset mission route, and simultaneously starts longitudinal position control, course position control and course attitude control;
in the third stage, the ground speed direction of the unmanned aerial vehicle is taken as a course angle to replace a magnetic course angle; the method comprises the steps that longitudinal position control, namely height control, is carried out, the height of a first navigation point is used as PID controller input, the current height and lifting speed of an unmanned aerial vehicle A are used as feedback, a target pitch angle between the unmanned aerial vehicle A and the first navigation point is calculated, and a cascade PID longitudinal control loop is formed with longitudinal attitude control;
the height control law is shown in the following formula:
Figure BDA00032851252100000211
Figure BDA00032851252100000212
in order to be a high feedback factor,
Figure BDA00032851252100000213
in order to be a high-degree integral coefficient,
Figure BDA00032851252100000214
for the feedback coefficient of the lifting speed, hcIs the altitude of the first waypoint, h is the current altitude of drone A, vdThe current lifting speed of the unmanned aerial vehicle A is obtained; thetacOutput unmanned aerial vehicle for controllerA target pitch angle of A;
the course position control is lateral offset control, a target course angle between the unmanned aerial vehicle A and a first waypoint is obtained through calculation by taking the current position of the unmanned aerial vehicle A and the lateral offset of the first waypoint as the input of a PID (proportion integration differentiation) controller, and then the target course angle is used as the input of a course attitude controller, and the rudder amount of the rudder of the unmanned aerial vehicle A is calculated and output through the PID controller;
the course position control law is shown as the following formula:
Figure BDA0003285125210000031
wherein ,
Figure BDA0003285125210000032
in order to be the coefficient of the side-offset feedback,
Figure BDA0003285125210000033
is the coefficient of integration of the offset distance,
Figure BDA0003285125210000034
is a lateral velocity feedback coefficient, and Delta L is the current lateral offset distance of the unmanned aerial vehicle A, veFor the current lateral velocity, psi, of drone AcAnd outputting the target course angle of the unmanned aerial vehicle A to the controller.
The course attitude control law is shown as the following formula:
Figure BDA0003285125210000035
wherein ,
Figure BDA0003285125210000036
the feedback coefficient of the course angle is shown as,
Figure BDA0003285125210000037
is the integral coefficient of the heading angle,
Figure BDA0003285125210000038
is a course angular velocity feedback coefficient, psi is the current course angle of the unmanned aerial vehicle A, r is the current course angular velocity of the unmanned aerial vehicle A, deltarThe rudder amount of the unmanned aerial vehicle A output by the controller.
When tracking each waypoint on the mission route, the roll outer ring of the unmanned aerial vehicle A inputs the course and the yaw distance from each waypoint, and performs coordinated turning together with course control, and the controller outputs a target roll angle
Figure BDA0003285125210000039
And then outputting the aileron rudder amount of the unmanned aerial vehicle A according to a rolling attitude control law.
The roll outer-loop control law is shown as the following formula:
Figure BDA00032851252100000310
wherein ,
Figure BDA00032851252100000311
in order to be the coefficient of the side-offset feedback,
Figure BDA00032851252100000312
is the coefficient of integration of the offset distance,
Figure BDA00032851252100000313
as a lateral velocity feedback coefficient, KYRAnd the feedback coefficient of the heading angle is shown.
Step seven, in the third stage, when the GPS or the measurement and control data link is abnormal and the abnormal time is less than the set time, controlling the unmanned aerial vehicle to keep the course, the height and the speed unchanged until the data are normal; otherwise, if the abnormal time exceeds the set time, the unmanned aerial vehicle is controlled to keep the constant angular velocity hovering.
The invention has the advantages that:
(1) the invention relates to a control method for catapult takeoff of an unmanned aerial vehicle, which designs the working process and control law output of rocket ignition and engine starting at the takeoff section, ensures the reliability of a system, realizes the full-autonomous takeoff process, and can realize one-key takeoff through the operation of a ground station;
(2) according to the control method for catapult take-off of the unmanned aerial vehicle, protection threshold values such as a pitch angle, a roll angle and a height are preset in a preparation stage before the unmanned aerial vehicle takes off, and target state values of the unmanned aerial vehicle are controlled to be within a protection threshold in flight, so that the flight safety of the unmanned aerial vehicle is guaranteed;
(3) the invention relates to a control method for catapult takeoff of an unmanned aerial vehicle, which makes corresponding logic judgment aiming at the situation of rocket dummy bomb possibly occurring after takeoff so as to reduce the loss caused by the occurrence of the dummy bomb to the maximum extent;
(4) the invention relates to a control method for catapult takeoff of an unmanned aerial vehicle, which is used for formulating a corresponding control strategy and protection logic aiming at GPS or communication data link interference possibly occurring in the flight of the unmanned aerial vehicle;
(5) according to the control method for the catapult takeoff of the unmanned aerial vehicle, when the magnetic heading measurement of the unmanned aerial vehicle is interfered by magnetism and cannot be used, an additional sensor is not needed, the ground speed direction can be measured through the GPS, the ground speed direction is used as the input of a control algorithm, and therefore the heading control of the unmanned aerial vehicle is achieved, and the control method has the advantages of being low in cost and high in reliability.
Drawings
FIG. 1 is a flow chart of a takeoff control method of an catapult takeoff unmanned aerial vehicle of the invention;
FIG. 2 is a flow chart of the catapult takeoff of an unmanned aerial vehicle in an embodiment of the invention;
fig. 3 is a longitudinal control block diagram of the unmanned aerial vehicle according to the embodiment of the present invention;
FIG. 4 is a block diagram of a course control of an unmanned aerial vehicle according to an embodiment of the present invention;
fig. 5 is a block diagram of lateral control of the unmanned aerial vehicle according to the embodiment of the present invention.
Detailed Description
Specific embodiments of the present invention will be described below with reference to the accompanying drawings.
The invention provides a takeoff control method of an ejection takeoff unmanned aerial vehicle, which comprises a first stage of rocket ignition; in the second stage, the unmanned aerial vehicle climbs to a safe height; and a third phase of entering the first waypoint of the business route from the safe altitude;
as shown in fig. 1, the specific steps are as follows:
the method comprises the steps that firstly, an unmanned aerial vehicle A to be launched is electrified, a launcher is installed for standby, each control plane keeps a middle position, and a pitch angle, a roll angle and a course angle of catapult takeoff, a lower flight altitude limit and a preset mission air line are initialized.
The control surface of the unmanned aerial vehicle comprises ailerons, a rudder and an elevator; the takeoff pitch angle is set according to the pitch angle of the ejection frame, the roll angle is set to be 0 degrees, and the heading angle is set to be a standby heading angle before takeoff; the lower limit of the flight height is the lowest flight height of the unmanned aerial vehicle relative to the ground altitude of the airport when the unmanned aerial vehicle executes a mission air route, and the safety height of the unmanned aerial vehicle is the ground altitude plus the lower limit of the flight height; the mission route consists of a plurality of waypoints, and each waypoint comprises latitude and longitude, height, airspeed and other information;
secondly, monitoring a control instruction of the ground station in real time by the unmanned aerial vehicle A, and entering a takeoff state from a ground state after receiving an effective takeoff instruction;
the unmanned aerial vehicle and the ground station mutually transmit data through a wireless data link;
thirdly, a flight control system of the unmanned aerial vehicle A sends a signal to control the rocket to be ignited, the rocket and the unmanned aerial vehicle A are ejected together, and the first stage of takeoff is started;
the rocket ignition signal is high level effective;
fourthly, after the rocket is ignited, the flight control system judges the ground speed and the airspeed of the unmanned aerial vehicle A, and when the ground speed and the airspeed of the unmanned aerial vehicle A are larger than set thresholds, the rocket is ignited successfully, and the second stage is started; and if the ground speed or the airspeed is far lower than a set threshold value after the rocket is ignited for a period of time, considering that the rocket is ignited unsuccessfully, stopping the take-off process, and starting the engine to shut down the vehicle.
In the first stage and the second stage, the rudder of the unmanned aerial vehicle A maintains a middle position, and the longitudinal attitude control and the rolling attitude control are started; and the target pitch angle and the target roll angle of the unmanned aerial vehicle do not exceed the set threshold through the output amplitude limit of the PID controller.
Longitudinal attitude control to initiateThe preset takeoff pitch angle is used as the input of a PID controller, the current pitch angle and pitch angle speed of the unmanned aerial vehicle A are used as feedback, and the rudder amount delta of the output elevator is calculatedeKeeping the unmanned aerial vehicle A at the set takeoff and climb angle;
rudder quantity delta of the output elevatoreThe calculation formula is as follows:
Figure BDA0003285125210000051
wherein ,
Figure BDA0003285125210000052
as a feedback factor of the pitch angle,
Figure BDA0003285125210000053
as an integral coefficient of the pitch angle,
Figure BDA0003285125210000054
for pitch rate feedback coefficient, theta0Is the initial set pitch angle, theta is the current pitch angle of the unmanned aerial vehicle A, q is the current pitch angle speed of the unmanned aerial vehicle A;
the roll attitude control keeps the roll angle of the unmanned aerial vehicle A at 0 degree, the target roll angle 0 degree initially set by the unmanned aerial vehicle A is used as the input of a PID controller, the current roll angle and the roll angular speed of the unmanned aerial vehicle A are used as feedback, and the rudder quantity delta of the output aileron is calculateda；
Rudder quantity delta of output aileronaThe calculation formula is as follows:
Figure BDA0003285125210000055
wherein ,
Figure BDA0003285125210000056
as a feedback coefficient of the roll angle,
Figure BDA0003285125210000057
is product of roll angleThe coefficient of the component is divided into a plurality of coefficients,
Figure BDA0003285125210000058
as a feedback coefficient of the roll angular velocity,
Figure BDA0003285125210000059
for the roll angle to be initially set up,
Figure BDA00032851252100000510
is the current roll angle of drone a and p is the current roll angular velocity of drone a.
Step five, the flight control system judges the current height of the unmanned aerial vehicle A in real time, when the unmanned aerial vehicle A reaches the safe height, the third stage is entered, the flight control system sends a signal to control the engine to start, the engine throttle is linearly increased from the idle throttle to the climbing throttle, and the unmanned aerial vehicle A is separated from the rocket;
the engine starting signal is active at a high level; when the unmanned aerial vehicle A reaches the safe height, the rocket ignition signal becomes low;
step six, after entering the third stage, the flight control system controls the unmanned aerial vehicle A to fly to a first waypoint of a preset mission route, and simultaneously starts longitudinal position control, course position control and course attitude control;
in the third stage, the ground speed direction of the unmanned aerial vehicle is taken as a course angle to replace a magnetic course angle;
as shown in fig. 3, the height of the first waypoint is used as the input of a PID controller, the current height and the lifting speed of the unmanned aerial vehicle a are used as feedback, the target pitch angle between the unmanned aerial vehicle a and the first waypoint is calculated, and a cascade PID longitudinal control loop is formed with the longitudinal attitude control;
the height control law is shown in the following formula:
Figure BDA00032851252100000511
Figure BDA00032851252100000512
in order to be a high feedback factor,
Figure BDA00032851252100000513
in order to be a high-degree integral coefficient,
Figure BDA00032851252100000514
for the feedback coefficient of the lifting speed, hcIs the altitude of the first waypoint, h is the current altitude of drone A, vdThe current lifting speed of the unmanned aerial vehicle A is obtained; thetacAnd outputting the target pitch angle of the unmanned aerial vehicle A to the controller.
As shown in fig. 4, the current position of the unmanned aerial vehicle a and the yaw distance of the first waypoint are used as the input of a PID controller, a target course angle between the unmanned aerial vehicle a and the first waypoint is obtained by calculation, and then the target course angle is used as the input of a course attitude controller, and the rudder amount of the rudder of the unmanned aerial vehicle a is calculated and output by the PID controller;
the course position control law is shown as the following formula:
Figure BDA00032851252100000515
wherein ,
Figure BDA00032851252100000516
in order to be the coefficient of the side-offset feedback,
Figure BDA00032851252100000517
is the coefficient of integration of the offset distance,
Figure BDA00032851252100000518
is a lateral velocity feedback coefficient, and Delta L is the current lateral offset distance of the unmanned aerial vehicle A, veFor the current lateral velocity, psi, of drone AcAnd outputting the target course angle of the unmanned aerial vehicle A to the controller.
The course attitude control law is shown as the following formula:
Figure BDA0003285125210000061
wherein ,
Figure BDA0003285125210000062
the feedback coefficient of the course angle is shown as,
Figure BDA0003285125210000063
is the integral coefficient of the heading angle,
Figure BDA0003285125210000064
is a course angular velocity feedback coefficient, psi is the current course angle of the unmanned aerial vehicle A, r is the current course angular velocity of the unmanned aerial vehicle A, deltarThe rudder amount of the unmanned aerial vehicle A output by the controller.
As shown in FIG. 5, when tracking each waypoint on the mission route, the roll outer ring of UAV A inputs the course and yaw from each waypoint, and performs a coordinated turn with course control, and the controller outputs the target roll angle
Figure BDA0003285125210000065
And then outputting the aileron rudder amount of the unmanned aerial vehicle A according to a rolling attitude control law.
The roll outer-loop control law is shown as the following formula:
Figure BDA0003285125210000066
wherein ,
Figure BDA0003285125210000067
in order to be the coefficient of the side-offset feedback,
Figure BDA0003285125210000068
is the coefficient of integration of the offset distance,
Figure BDA0003285125210000069
as a lateral velocity feedback coefficient, KYRAnd the feedback coefficient of the heading angle is shown.
Step seven, in the third stage, when the GPS or the measurement and control data link is abnormal and the abnormal time is less than the set time, controlling the unmanned aerial vehicle to keep the course, the height and the speed unchanged until the data are normal; otherwise, if the abnormal time exceeds the set time, the unmanned aerial vehicle is controlled to keep the constant angular velocity hovering.
Examples
As shown in fig. 2, the specific process is as follows:
(1) the unmanned aerial vehicle is electrified, is arranged in a launcher to be ready to take off, each control surface keeps a middle position, a take-off target pitch angle, a target roll angle and a target yaw angle are initialized, a flight height lower limit is set, and a mission air route is preset.
The control plane of the unmanned aerial vehicle comprises ailerons, a rudder and an elevator, the pitch angle of a takeoff target is set according to the pitch angle of the catapult frame, the pitch angle is 25 degrees in the example, namely the takeoff control unmanned aerial vehicle climbs at the pitch angle of 25 degrees; the target rolling angle is set to be 0, and the target yaw angle is set to be a standby course angle before takeoff; each navigation point of the mission route comprises information such as longitude and latitude, height, flying airspeed and the like. The lower limit of the flight height is the lowest flight height of the unmanned aerial vehicle relative to the ground altitude of the airport when the unmanned aerial vehicle executes a mission flight path, the altitude of the airport is about 1400 meters in the embodiment, and the lower limit of the flight height is set to 90 meters, so that the altitude of the unmanned aerial vehicle when flying is not lower than 1490 meters; the first waypoint altitude of the mission route is set to 1600 meters.
(2) And (4) after the unmanned aerial vehicle receives the effective takeoff instruction sent by the ground receiving station, the unmanned aerial vehicle enters a takeoff state from the ground state, the takeoff control system starts to execute a takeoff control process, and the step (3) is entered.
The unmanned aerial vehicle and the ground station mutually transmit data through a wireless data link, the unmanned aerial vehicle starts to detect a control instruction of the ground station after being electrified and defecated, and automatically enters a take-off process after receiving a take-off instruction;
(3) the specific method of the rocket ignition takeoff control process is as follows:
(3.1) the flight control system sends out a switch signal to control the rocket to ignite, and the rocket and the unmanned aerial vehicle pop up together; after the rocket is ignited, the engine throttle is set at 30% idle speed; the rocket ignition signal lasts for 2 seconds, so that the unmanned aerial vehicle is ensured to climb to a safe height, and then the rocket ignition signal becomes low;
after the flight control system receives a takeoff instruction, a program counter in flight control software automatically starts timing to control the execution sequence and duration of each subsequent instruction;
after the rocket is ignited to take off, the rudder of the unmanned aerial vehicle keeps a neutral position, and longitudinal attitude control and rolling attitude control are started.
The target pitch angle of the longitudinal attitude control is kept at 25 degrees, the target pitch angle of 25 degrees of the unmanned aerial vehicle is used as the input of a PID controller, and the rudder amount of an elevator is calculated and output through the controller, so that the unmanned aerial vehicle keeps the takeoff and climb angle of 25 degrees and can smoothly reach the safe height; the roll attitude control takes the target roll angle of the unmanned aerial vehicle of 0 degree as the input of a PID controller, and the controller calculates and outputs the rudder amount of the ailerons, so that the roll angle of the unmanned aerial vehicle is kept at 0 degree in the take-off and ejection process, and the unmanned aerial vehicle is prevented from causing pneumatic performance deterioration or generating transverse and lateral velocity components due to roll;
after the rocket is ignited to take off, the flight control system judges the ground speed and the airspeed of the unmanned aerial vehicle in real time, when the ground speed of the unmanned aerial vehicle is greater than 5m/s and the airspeed is greater than 10m/s, the rocket is successfully ignited, otherwise, the take-off process is stopped and the engine is turned off.
(3.2) after the rocket is ignited, the unmanned aerial vehicle climbs under the boosting of the rocket, meanwhile, the flight control system judges whether the current height of the unmanned aerial vehicle reaches a safe height in real time, namely whether the current flight height is greater than the lower limit of the flight height of 1490 m, and when the current height of the unmanned aerial vehicle is greater than the lower limit of the flight height of 1490 m and lasts for more than 1 second, the flight control system sends a switch signal to control the starting of an engine, the starting signal lasts for 5 seconds, the throttle is increased to 80% from 30% after the engine is started, the throttle is increased in a mode of softening by an instruction, the linear increase is carried out within 2 seconds, and then the starting signal of the engine becomes low;
and (3.3) after the engine is started, the flight control system controls the unmanned aerial vehicle to fly to a first target waypoint of a preset mission route, and simultaneously starts course attitude control and outer ring position control, wherein the outer ring position control comprises longitudinal position control and course position control.
In the steps (3.1) and (3.2), the rocket ignition signal and the engine starting signal sent by the flight control system are both high-level effective;
in the step (3.3), longitudinal position control, namely height control, is carried out, the target height of the unmanned aerial vehicle is used as the input of a PID controller, a target pitch angle is calculated and output through the controller, and a longitudinal control loop of cascade PID is formed with longitudinal attitude control; in the embodiment, after the target waypoint is switched, the altitude and gradient control is executed, namely the unmanned aerial vehicle is controlled to carry out altitude control by using an oblique line formed by the current point and the target waypoint;
in the step (3.3), the course position control, namely the lateral offset control, ensures the air route tracking precision of the unmanned aerial vehicle; the position control takes the lateral offset distance between the current position of the unmanned aerial vehicle and a target navigation point as the input of a PID controller, and a target course angle is obtained through calculation of the controller; the target course angle is used as the input of a course attitude controller, and the output rudder amount of the rudder is calculated through a PID controller;
in the step (3.3), when a target course is tracked, the unmanned aerial vehicle roll attitude control and the course control are coordinated to turn, the controller inputs the course deviation and the lateral deviation, the target roll angle is output through the PID controller, and then the auxiliary wing rudder amount is output through the roll attitude control in the step (3.1).
In the step (3.3), because the unmanned aerial vehicle is provided with the launch box and is influenced by ferromagnetic interference, the work of the magnetic compass on the unmanned aerial vehicle can be interfered by the magnetic field of the soft magnetic body, so that the magnetic heading angle measured by the magnetic compass has larger deviation and even can not be used, and the magnetic heading angle can be recovered to be normal after the unmanned aerial vehicle takes off for a period of time, therefore, in the example, the direction of the flight path angle, namely the ground speed direction, is taken as the heading angle in the take-off section of the unmanned aerial vehicle to replace the heading angle of the magnetic compass; after the unmanned aerial vehicle takes off, judging the ground speed of the unmanned aerial vehicle in real time, and taking the ground speed direction of the unmanned aerial vehicle as a course angle when the local speed is more than 5 m/s;
performing the following protection while performing step (3.3):
(a) the unmanned aerial vehicle executes pitch angle protection and roll angle protection to prevent overlarge pitch angle and roll angle in flight, so that the aircraft stalls;
the specific operation is as follows: outputting amplitude limit through a controller, so that the target pitch angle and the target roll angle of the unmanned aerial vehicle do not exceed a set threshold;
(b) after the unmanned aerial vehicle reaches the safe altitude, the unmanned aerial vehicle executes altitude protection, and the target altitude for controlling the unmanned aerial vehicle to fly is not lower than the lower altitude limit of 1490 m;
(c) the unmanned aerial vehicle executes communication interruption protection: if the GPS or the measurement and control data link is abnormal in flight, if the abnormal time is less than 5 minutes, controlling the unmanned aerial vehicle to keep the course, the height and the speed unchanged until the data is recovered to be normal; and if the abnormal time exceeds 5 minutes, controlling the unmanned aerial vehicle to keep hovering at a constant angular rate.

Claims (3)

1. A control method for catapult take-off of an unmanned aerial vehicle is characterized by comprising the following steps:
firstly, powering on an unmanned aerial vehicle A to be launched, loading the unmanned aerial vehicle A into a launcher for standby, keeping each control plane at a middle position, and initializing a pitch angle, a roll angle and a course angle of catapult takeoff, a lower limit of flight altitude and a preset mission air line;
secondly, monitoring a control instruction of the ground station in real time by the unmanned aerial vehicle A, and entering a takeoff state from a ground state after receiving an effective takeoff instruction;
thirdly, a flight control system of the unmanned aerial vehicle A sends a signal to control the rocket to be ignited, the rocket and the unmanned aerial vehicle A are ejected together, and the first stage of takeoff is started;
fourthly, after the rocket is ignited, the flight control system judges the ground speed and the airspeed of the unmanned aerial vehicle A, and when the ground speed and the airspeed of the unmanned aerial vehicle A are larger than set thresholds, the rocket is ignited successfully, and the second stage is started; if the ground speed or the airspeed is far lower than a set threshold value after the rocket is ignited for a period of time, considering that the rocket is ignited to fail, stopping a take-off process, and starting the engine to shut down the vehicle;
step five, the flight control system judges the current height of the unmanned aerial vehicle A in real time, when the unmanned aerial vehicle A reaches the safe height, the third stage is entered, the flight control system sends a signal to control the engine to start, the engine throttle is linearly increased from the idle throttle to the climbing throttle, and the unmanned aerial vehicle A is separated from the rocket;
step six, after entering the third stage, the flight control system controls the unmanned aerial vehicle A to fly to a first waypoint of a preset mission route, and simultaneously starts longitudinal position control, course position control and course attitude control;
step seven, in the third stage, when the GPS or the measurement and control data link is abnormal and the abnormal time is less than the set time, controlling the unmanned aerial vehicle to keep the course, the height and the speed unchanged until the data are normal; otherwise, if the abnormal time exceeds the set time, the unmanned aerial vehicle is controlled to keep the constant angular velocity hovering.
2. The method for controlling catapult-assisted take-off of an unmanned aerial vehicle as claimed in claim 1, wherein in the fourth step, in the first stage and the second stage, the rudder of the unmanned aerial vehicle A maintains a neutral position, and the longitudinal attitude control and the rolling attitude control are started;
the longitudinal attitude control takes an initial preset takeoff pitch angle as PID controller input, takes the current pitch angle and pitch angle speed of the unmanned aerial vehicle A as feedback, and calculates and outputs rudder amount delta of the elevatoreKeeping the unmanned aerial vehicle A at the set takeoff and climb angle;
rudder quantity delta of the output elevatoreThe calculation formula is as follows:
Figure FDA0003285125200000011
wherein ,
Figure FDA0003285125200000012
as a feedback factor of the pitch angle,
Figure FDA0003285125200000013
as an integral coefficient of the pitch angle,
Figure FDA0003285125200000014
for pitch rate feedback coefficient, theta0For the initially set pitch angle, θ is the current pitch of drone AThe angle q is the current pitch angle speed of the unmanned aerial vehicle A;
the roll attitude control keeps the roll angle of the unmanned aerial vehicle A at 0 degree, the target roll angle 0 degree initially set by the unmanned aerial vehicle A is used as the input of a PID controller, the current roll angle and the roll angular speed of the unmanned aerial vehicle A are used as feedback, and the rudder quantity delta of the output aileron is calculateda；
Rudder quantity delta of output aileronaThe calculation formula is as follows:
Figure FDA0003285125200000015
wherein ,
Figure FDA0003285125200000016
as a feedback coefficient of the roll angle,
Figure FDA0003285125200000017
as an integral coefficient of the roll angle,
Figure FDA0003285125200000018
as a feedback coefficient of the roll angular velocity,
Figure FDA0003285125200000019
for the roll angle to be initially set up,
Figure FDA00032851252000000110
is the current roll angle of drone a and p is the current roll angular velocity of drone a.
3. The method for controlling catapult-assisted take-off of an unmanned aerial vehicle as claimed in claim 1, wherein in the sixth stage, the ground speed direction of the unmanned aerial vehicle is taken as a heading angle instead of a magnetic heading angle; the method comprises the steps that longitudinal position control, namely height control, is carried out, the height of a first navigation point is used as PID controller input, the current height and lifting speed of an unmanned aerial vehicle A are used as feedback, a target pitch angle between the unmanned aerial vehicle A and the first navigation point is calculated, and a cascade PID longitudinal control loop is formed with longitudinal attitude control;
the height control law is shown in the following formula:
Figure FDA0003285125200000021
Figure FDA0003285125200000022
in order to be a high feedback factor,
Figure FDA0003285125200000023
in order to be a high-degree integral coefficient,
Figure FDA0003285125200000024
for the feedback coefficient of the lifting speed, hcIs the altitude of the first waypoint, h is the current altitude of drone A, vdThe current lifting speed of the unmanned aerial vehicle A is obtained; thetacOutputting a target pitch angle of the unmanned aerial vehicle A to the controller;
the course position control is lateral offset control, a target course angle between the unmanned aerial vehicle A and a first waypoint is obtained through calculation by taking the current position of the unmanned aerial vehicle A and the lateral offset of the first waypoint as the input of a PID (proportion integration differentiation) controller, and then the target course angle is used as the input of a course attitude controller, and the rudder amount of the rudder of the unmanned aerial vehicle A is calculated and output through the PID controller;
the course position control law is shown as the following formula:
Figure FDA0003285125200000025
wherein ,
Figure FDA0003285125200000026
in order to be the coefficient of the side-offset feedback,
Figure FDA0003285125200000027
is the coefficient of integration of the offset distance,
Figure FDA0003285125200000028
is a lateral velocity feedback coefficient, and Delta L is the current lateral offset distance of the unmanned aerial vehicle A, veFor the current lateral velocity, psi, of drone AcThe target course angle of the unmanned aerial vehicle A is output by the controller;
the course attitude control law is shown as the following formula:
Figure FDA0003285125200000029
wherein ,
Figure FDA00032851252000000210
the feedback coefficient of the course angle is shown as,
Figure FDA00032851252000000211
is the integral coefficient of the heading angle,
Figure FDA00032851252000000212
is a course angular velocity feedback coefficient, psi is the current course angle of the unmanned aerial vehicle A, r is the current course angular velocity of the unmanned aerial vehicle A, deltarThe rudder amount of the unmanned aerial vehicle A is output by the controller;
when tracking each waypoint on the mission route, the roll outer ring of the unmanned aerial vehicle A inputs the course and the yaw distance from each waypoint, and performs coordinated turning together with course control, and the controller outputs a target roll angle
Figure FDA00032851252000000213
Then outputting the aileron rudder amount of the unmanned aerial vehicle A according to a rolling attitude control law;
the roll outer-loop control law is shown as the following formula:
Figure FDA00032851252000000214
wherein ,
Figure FDA00032851252000000215
in order to be the coefficient of the side-offset feedback,
Figure FDA00032851252000000216
is the coefficient of integration of the offset distance,
Figure FDA00032851252000000217
as a lateral velocity feedback coefficient, KYRAnd the feedback coefficient of the heading angle is shown.
CN202111144317.9A 2021-09-28 2021-09-28 Control method for catapult-assisted take-off of unmanned aerial vehicle Active CN113835438B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202111144317.9A CN113835438B (en) 2021-09-28 2021-09-28 Control method for catapult-assisted take-off of unmanned aerial vehicle

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202111144317.9A CN113835438B (en) 2021-09-28 2021-09-28 Control method for catapult-assisted take-off of unmanned aerial vehicle

Publications (2)

Publication Number Publication Date
CN113835438A true CN113835438A (en) 2021-12-24
CN113835438B CN113835438B (en) 2023-05-23

Family

ID=78967105

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202111144317.9A Active CN113835438B (en) 2021-09-28 2021-09-28 Control method for catapult-assisted take-off of unmanned aerial vehicle

Country Status (1)

Country Link
CN (1) CN113835438B (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114399897A (en) * 2022-03-28 2022-04-26 北京航空航天大学 Unmanned aerial vehicle swarm dense continuous emission control system based on high-speed optical fiber bus
CN114740874A (en) * 2022-03-22 2022-07-12 西安爱生技术集团有限公司 Unmanned aerial vehicle rocket boosting launching rolling attitude control method
CN114740902A (en) * 2022-06-13 2022-07-12 成都飞机工业（集团）有限责任公司 Rocket-assisted launching and taking-off control method for unmanned aerial vehicle with flying wing layout

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109941422A (en) * 2019-03-22 2019-06-28 北京理工大学 A kind of the aerodynamic configuration structure and control method of folding wings missile-borne unmanned plane
US20200148389A1 (en) * 2018-11-14 2020-05-14 Huan-Jung Lin Take-off apparatus and method for unmanned aerial vehicle without landing gear
CN111309041A (en) * 2020-03-05 2020-06-19 成都飞机工业（集团）有限责任公司 Catapult takeoff pull-up control method

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20200148389A1 (en) * 2018-11-14 2020-05-14 Huan-Jung Lin Take-off apparatus and method for unmanned aerial vehicle without landing gear
CN109941422A (en) * 2019-03-22 2019-06-28 北京理工大学 A kind of the aerodynamic configuration structure and control method of folding wings missile-borne unmanned plane
CN111309041A (en) * 2020-03-05 2020-06-19 成都飞机工业（集团）有限责任公司 Catapult takeoff pull-up control method

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
冉海霞;: "某型无人机火箭弹射起飞俯仰姿态角优化设计", 飞行力学 *

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114740874A (en) * 2022-03-22 2022-07-12 西安爱生技术集团有限公司 Unmanned aerial vehicle rocket boosting launching rolling attitude control method
CN114399897A (en) * 2022-03-28 2022-04-26 北京航空航天大学 Unmanned aerial vehicle swarm dense continuous emission control system based on high-speed optical fiber bus
CN114740902A (en) * 2022-06-13 2022-07-12 成都飞机工业（集团）有限责任公司 Rocket-assisted launching and taking-off control method for unmanned aerial vehicle with flying wing layout

Also Published As

Publication number Publication date
CN113835438B (en) 2023-05-23

Similar Documents

Publication Publication Date Title
CN113835438B (en) Control method for catapult-assisted take-off of unmanned aerial vehicle
CN109597427B (en) Bomb random attack planning method and system based on unmanned aerial vehicle
Jourdan et al. Enhancing UAV survivability through damage tolerant control
CN109856972B (en) Robust fault-tolerant tracking control method for unmanned helicopter
CN110908405B (en) Control method for concentric circle flight of fixed wing unmanned aerial vehicle
US10782707B2 (en) Maintaining a stable phase difference between multiple tethered vehicles lifting a payload
WO2018047549A1 (en) Spacecraft and landing method therefor
US20180222583A1 (en) UAV Booster Aircraft for Takeoff and Climb Assist
You et al. A guidance and control law design for precision automatic take-off and landing of fixed-wing UAVs
CN114200827B (en) Multi-constraint double-channel control method for supersonic large maneuvering target
Stojcsics et al. Fixed-wing small-size UAV navigation methods with HIL simulation for AERObot autopilot
CN109436363B (en) Catapult-assisted take-off control method for large-overload folding wing type unmanned aerial vehicle
CN112429265A (en) Gun-launched takeoff control method for gun-launched unmanned aerial vehicle
Zaludin et al. Challenges and trends of changing from hover to forward flight for a converted hybrid fixed wing vtol uas from automatic flight control system perspective
US11544161B1 (en) Identifying anomalous sensors
Zaludin et al. Automatic flight control requirements for transition flight phases when converting long endurance fixed wing UAV to VTOL aircraft
CN113934223B (en) Unmanned autorotation gyroplane landing control method
UA56365C2 (en) Method for controlling aerospace system for putting payloads into orbit
CN114153226B (en) Unmanned aerial vehicle view field keeping and guiding method and system assisted by dynamic sight line information
Wise First flight of the X-45A unmanned combat air vehicle (UCAV)
US5430449A (en) Missile operable by either air or ground launching
CN108033025B (en) Thrust control system of aircraft engine
Stojcsics Flight safety improvements for small size unmanned aerial vehicles
CN112198891B (en) Multi-gyroplane autonomous recovery method
US20230205204A1 (en) Method for controlling a robot-aircraft and corresponding control system

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
GR01 Patent grant
GR01 Patent grant