CN107608366B - Multi-wing umbrella unmanned aerial vehicle system based on event trigger - Google Patents
Multi-wing umbrella unmanned aerial vehicle system based on event trigger Download PDFInfo
- Publication number
- CN107608366B CN107608366B CN201710783381.9A CN201710783381A CN107608366B CN 107608366 B CN107608366 B CN 107608366B CN 201710783381 A CN201710783381 A CN 201710783381A CN 107608366 B CN107608366 B CN 107608366B
- Authority
- CN
- China
- Prior art keywords
- parafoil
- module
- unmanned aerial
- control
- aerial vehicle
- 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.)
- Active
Links
Images
Landscapes
- Pharmaceuticals Containing Other Organic And Inorganic Compounds (AREA)
- Control Of Position, Course, Altitude, Or Attitude Of Moving Bodies (AREA)
Abstract
The multi-parafoil unmanned aerial vehicle system based on event triggering comprises a ground control station and a plurality of parafoil unmanned aerial vehicles, wherein each parafoil unmanned aerial vehicle is provided with a measuring sensor module, a parafoil driving control module and a steering engine; the parafoil unmanned aerial vehicle is provided with a driving model detection module; when the real-time attitude change of the parafoil unmanned aerial vehicle exceeds a change allowance value, triggering an event emergency module; the event emergency module enables the parafoil driving control module to stop working, and the parafoil unmanned aerial vehicle enters a free flight state; specific input value zeta of current over time obtained by parafoil drive control inversion modeloptimizeThe parafoil driving control module of the input parafoil unmanned aerial vehicle. The invention has the advantage that the parafoil unmanned aerial vehicle only needs to acquire data and execute commands and does not need to carry out operation and is triggered based on events.
Description
Technical Field
The invention relates to the field of homing trajectory control of a plurality of parafoil unmanned aerial vehicles.
Background
The parafoil unmanned aerial vehicle is a parachute with controllability and gliding property, and has wide requirements and applications in the fields of military affairs, aerospace and the like. Then, whether or not safe landing at a predetermined landing point is a target of the entire parafoil control. The state of drift with wind often makes the landing deviation be several kilometers or even tens of kilometers, so it is extremely important to adopt advanced control method to accomplish accurate air-drop and fixed point lossless.
The research institute and colleges for researching the parafoil overhead system in China mainly comprise northern aviation, southern aviation, aviation equipment research institute, aerospace life-saving equipment Limited airdrop department and the like, and the focus and the like provide the parafoil system track intelligent algorithm based on the chaotic particle swarm optimization algorithm; the study of the ursolic acid and the like is carried out by adopting PD control of fuzzy theory; and Zhao Min adopts an optimal control method, and the optimal homing track meeting the air drop requirement at the planning position. The research in this aspect is started later in China, and the experimental verification is less.
CN201510824172.5 discloses a parafoil unmanned aerial vehicle, which includes a data acquisition module and a flight control navigation computer for analyzing and processing data acquired by the data acquisition module and sending control instructions, wherein the flight control navigation computer includes an inertia resolving processor, a data input and output processor and a logic processor, and the logic processor includes a navigation controller and a stability augmentation controller; the execution mechanism is used for executing a control instruction sent by the flight control navigation computer and controlling the flight state of the parafoil unmanned aerial vehicle to change; a ground station module: the ground station module comprises a bottom surface measurement and control link communication module for ensuring the reliability of data communication, a data display module for displaying the data such as the position, the flight attitude and the like of the parafoil unmanned aerial vehicle and a ground station for controlling the task planning and the remote control action of the parafoil unmanned aerial vehicle, and the ground station is connected with the flight control navigation computer through the bottom surface measurement and control link communication module; the output end of the data acquisition module is connected with the input end of the flight control navigation computer through the analog-to-digital conversion module, and the output end of the flight control navigation computer is connected with the signal input end of the controller of the actuating mechanism.
The parafoil unmanned aerial vehicle aircraft is combined with a ground station, the ground station bears the tasks of mission planning and generation of remote control action instructions, and the parafoil unmanned aerial vehicle aircraft bears resolving tasks except the mission planning and the remote control action instructions, so that the requirement on the operational capability of the aircraft is reduced to a certain extent. However, in addition to mission planning and generation of remote control action commands, the parafoil unmanned aerial vehicle needs to resolve its own attitude and convert operator commands from a ground station into execution commands for an actuator. The parafoil unmanned aerial vehicle has high resolving and analyzing requirements on a flight control navigation computer. Moreover, the parafoil unmanned aerial vehicle is only suitable for the situation that only one parafoil unmanned aerial vehicle is arranged, the travel planning and control problems of a plurality of parafoil unmanned aerial vehicle systems are not considered, and the parafoil unmanned aerial vehicle cannot deal with the emergency events such as severe shaking of the parafoil unmanned aerial vehicle due to airflow.
Disclosure of Invention
The invention aims to provide a multi-parafoil unmanned aerial vehicle system based on event triggering, which is used for parafoil unmanned aerial vehicles and does not need to perform operation, and only needs to acquire data and execute commands.
Many parafoil unmanned aerial vehicle system based on event trigger comprises ground control station and a plurality of parafoil unmanned aerial vehicle, and every parafoil unmanned aerial vehicle has the measuring transducer module, parafoil drive control module and steering wheel, and parafoil drive control module makes steering wheel control rope length, and the measuring transducer module measures this parafoil unmanned aerial vehicle's real-time information, and real-time information includes: acceleration information, angular velocity information, orientation determined by the magnetometer and length of the steering rope; the ground control station is provided with a track planning module;
the method is characterized in that: the real-time information comprises the actual driving current of the steering engine;
the ground control station is provided with a parafoil attitude resolving module, a parafoil attitude control module, an event emergency module, a parafoil drive identification module and a parafoil drive control inversion module; the parafoil unmanned aerial vehicle is provided with a driving model detection module;
the parafoil attitude calculation module receives the steering engine driving current information, the acceleration information, the angular velocity information and the control rope length information sent by the measurement sensor module and calculates the steering engine driving current information, the acceleration information, the angular velocity information and the control rope length information into corresponding parafoil unmanned aerial vehicle attitudes, sets a variation margin value of the parafoil attitude, and triggers the event emergency module when the real-time attitude variation of the parafoil unmanned aerial vehicle exceeds the variation margin value; the event emergency module enables the parafoil driving control module to stop working, and the parafoil unmanned aerial vehicle enters a free flight state;
parafoil drive identification module for establishing steering engine drive model
Wherein
The input of driving current, u (t) the output of the length of the control rope, A the control coefficient and B the state coefficient; the parafoil driving identification module completes the determination of a control coefficient A and a state coefficient B by a parameter estimation method, and inputs the control coefficient A and the state coefficient B into a driving model detection module and a parafoil driving control module of the parafoil unmanned aerial vehicle respectively;
optimal control line control curve uTARInputting a parafoil drive control inversion module, solving a parafoil drive control inversion model:
an objective function of
The constraint condition is
The state is constrained to
Wherein
The minimum current is output by the parafoil driving control module,
is the maximum current output by the parafoil driving control module,
as a function of the change of the current with time, the result being a specific input value of the current with time
Specific input value of current obtained by parafoil drive control inversion model along with time
The parafoil driving control module of the input parafoil unmanned aerial vehicle.
The parafoil driving control module only needs to input a current value from a ground control station into the actuating mechanism, the actuating mechanism can enable the length of the control rope to reach a required target, and the parafoil driving control module does not need to calculate the current value which is needed by the length of the control rope and corresponds to enable the actuating mechanism to act.
Further, the measurement sensor module continuously sends information to the parafoil attitude calculation module; after the event emergency module is triggered for a specified time, if the attitude change of the parafoil unmanned aerial vehicle still exceeds a change allowance value, the parafoil driving control module inputs the signal to the steering engine. Stabilize the electric current signal of parafoil unmanned aerial vehicle gesture.
Furthermore, the measurement sensor module comprises a current measurement module, an inertial sensing unit, a magnetometer, a GPD (general purpose display) locator and a wind speed measurement module.
Further, the process of determining the control coefficient A and the state coefficient B by the parafoil driving identification module comprises the following steps:
step 1: parameter identification interval [0, T ] recorded by current measurement module of parafoil receiving unmanned aerial vehicletest]Function of current change with time
Is recorded as
Step 2: recording the output of the length of the control rope, note
And step 3: solving for the minimum
Wherein T istestTime required for parameter identification;
and 4, step 4: will be provided with
Bringing in
Obtaining u (t) by numerical solution, and then solving
And then finishing the estimation of the parameters A and B by an intelligent optimization algorithm.
And further, the driving model detection module judges whether the output of the steering engine driving model is matched with the length information of the actual control rope, and when the output of the steering engine driving model is obviously not matched with the length information of the actual control rope, the driving model detection module triggers the event emergency module and transmits the real-time current of the driving control module and the length information of the current control rope to the ground control station. An obvious mismatch is that the difference between the actual steering rope length and the output of the steering engine drive model is greater than a set margin value.
Further, the track planning module comprises a multi-wing umbrella track homing model, a fully discrete unit for multi-wing umbrella track homing and an AMPL (amplitude modulation and amplitude modulation) optimization unit;
in the multi-wing umbrella track homing model, the kinematics model of the wing umbrella unmanned aerial vehicle is as follows:
wherein R is the total number of parafoil unmanned aerial vehicles, xr,yrAnd z represents the coordinate of the r-th parafoil unmanned aerial vehicle in a geodetic coordinate system, vrRepresents the horizontal flying speed of the r-th parafoil unmanned plane,
represents the horizontal wind speed measured by the r-th parafoil unmanned plane, vzIndicating the vertical drop velocity, theta, of the parafoil dronerIndicates the turning angle u of the r-th parafoil unmanned planerThe control rope length of the r-th parafoil unmanned plane is shown.
The limiting conditions of the motion area of each parafoil unmanned aerial vehicle are as follows:
safe distance x between parafoil unmanned aerial vehiclesmar,ymarThe following settings are set:
xr-xb≥xmar,yr-yb≥ymar；r＝1,2,...,R；b＝1,2,...,R；r≠b；
with the coordinates of the desired drop point and the turning angle as
The objective function is:
full discrete unit of multi-wing umbrella track homing willxr,yr,z,θr,urIn the time domain, NE sub-time intervals are separated, and the separated time is expressed as t ═ tm+hmτ, in each sub-time interval, the state variable is represented as:
ks is an integer;
the continuity conditions that the state variables must satisfy are:
the control variable is expressed as
Ku is an integer;
the continuity conditions that the control variables must satisfy are:
only in the continuity condition, m ═ 1, 2., NE-1;
the fully discrete kinematic equation is:
the constraint is fully discrete as:
the safe distance is fully discrete as:
the objective function of the fully discrete trajectory homing model is: (ii) a (ii) a (ii) a
The AMPL optimization unit optimizes and solves a fully discrete track homing model and an objective function thereof to obtain an optimal track and an optimal control curve of each parafoil unmanned aerial vehicle; solving the homing tracks of the parafoil unmanned aerial vehicles by taking the optimal track and the optimal control curve of each parafoil unmanned aerial vehicle as initial guesses of centralized optimization; verifying whether the verified homing track meets the constraint of the state variable, the continuity condition and the safety distance between any two parafoil robots; if so, inputting the optimal track and the optimal control curve into a parafoil drive control inversion module; if not, the optimal track and the optimal control curve are calculated again.
Further, a measurement sensor module of each parafoil unmanned aerial vehicle sends real-time information to a parafoil attitude calculation module; the ground control station is provided with a rolling time domain real-time control module and a parafoil drive control inversion module
Inputting the rolling time domain real-time control module, wherein the rolling time domain real-time control module is used for controlling the fixed interval time [0, T]Is equally divided into NZSegments, each segment having a time scale of T/NZThe rolling time domain real-time control module enables the AMPL optimization unit to optimize an optimal track and an optimal control curve once in each time scale; each parafoil unmanned aerial vehicle is provided with a rolling time domain real-time feedback control module which enables the steering engine to execute only each time
[0,T/NZ]And (7) a period of time.
Furthermore, the ground control station is provided with a homing track real-time display module, and the homing track real-time display module displays the optimal track, the optimal control curve and the GPS position information sent by the parafoil in real time.
The event trigger-based multi-wing umbrella unmanned aerial vehicle control method comprises the following steps:
the control part that parafoil unmanned aerial vehicle carried out:
1) each parafoil unmanned aerial vehicle measures this parafoil unmanned aerial vehicle's real-time information through the measuring sensor unit, and the real-time information includes: acceleration and angular velocity information, the orientation determined by the magnetometer, the actual driving current of the steering engine, the length of a control rope, real-time wind speed and GPS position information, and real-time information are transmitted to a ground control station;
2) receiving identification parameter information of a motion system sent by a ground control station, and storing the updated parameter information into a parafoil driving control module and a driving model detection module of each parafoil unmanned aerial vehicle; setting an output margin value of the length of the control rope in a driving model detection module, and triggering an event emergency module when the output of the length of the control rope of a parafoil driving control module steering engine is not accurately matched with the actual output of the length of the control rope; the parafoil driving control module controls a steering engine, and the steering engine changes the length of a control rope from the umbrella surface to a load;
3) each parafoil unmanned aerial vehicle receives a steering engine current input instruction sent by the parafoil driving control inversion module, and the parafoil driving control module enables the steering engine to control the length of a control rope to adjust the length of the control rope;
4) due to the working condition change of the parafoil unmanned aerial vehicle, the optimal homing track and the actual running track have certain deviation, and each parafoil unmanned aerial vehicle sends real-time information to a ground control station;
5) re-receiving a steering engine current input command sent by the ground control station every fixed time, and re-executing the steps 3-4;
6) the event emergency module has three main functions:
● when receiving a free flight command, the current drive module is stopped quickly.
● when receiving the attitude adjustment command, according to the current command instruction sent by the ground station, the steering engine is driven to stabilize the attitude of the parafoil unmanned aerial vehicle.
● when the output of the steering engine driving model is not accurately triggered by the matching of the actual length information of the control rope, the length information of the driving current detection module and the pull rope is rapidly collected and transmitted to the ground control station, and the emergency module of the ground control station is started.
The ground control station executes the following control steps:
1) the ground receiving station receives real-time information transmitted by the parafoil unmanned aerial vehicles and resolves the postures of the parafoils;
2) establishing a steering engine driving model for controlling a steering engine of the parafoil unmanned aerial vehicle, wherein the input of the steering engine is
The steering engine outputs the length of a control rope, a parameter estimation method is adopted, specific driving model parameter information is obtained through solving according to the information transmitted in the step 1, and the identified parameters are transmitted to all parafoil unmanned aerial vehicles;
3) establishing a plurality of parafoil unmanned aerial vehicle models for trajectory planning according to the position information and the wind speed information of each parafoil, inputting stay cord control variables, outputting the stay cord control variables as x, y, z and theta, wherein the parafoil unmanned aerial vehicle x, y and z are coordinates under a terrestrial coordinate system, and the theta represents a turning angle; setting control constraint, position constraint, safety distance constraint among all parafoils and parafoil flight airspace constraint, and setting a specific parafoil unmanned aerial vehicle landing point as a tracking target;
4) for a plurality of parafoil unmanned aerial vehicle kinematic models, an orthogonal configuration method is adopted, state variables x, y, z, theta and control variables u are dispersed in time and space to obtain a fully-dispersed model, and the homing trajectory control problem is changed into a nonlinear programming problem;
5) solving the nonlinear programming problem obtained in the step 4) by using a nonlinear optimization solver carried by the AMPL platform to obtain the optimal homing track and the optimal control curve. In order to accelerate the centralized optimization efficiency of a plurality of parafoil unmanned aerial vehicles, firstly, each parafoil unmanned aerial vehicle independently adopts orthogonal configuration, the homing tracks are optimized in parallel, then, the homing tracks are integrated into an initial guess of the centralized optimization, and the centralized optimization is completed;
6) putting the optimized result into a driving inversion module, taking the difference between the output of a pull rope of the steering engine driving model and the optimal control as a performance index, inverting to obtain current driving variable quantity, and transmitting the current driving variable quantity to each parafoil unmanned aerial vehicle;
7) and the ground control station receives the position information sent by the bottom parafoil control system in real time. Due to the change of the model, the working condition and the like, the preset track information and the real-time position information of the parafoil cannot be completely matched, a rolling optimization strategy is adopted, and the steps 5) to 6) are newly executed at intervals, and after the current driving variable quantity is obtained through calculation, the current driving variable quantity is sent to each parafoil unmanned aerial vehicle. Meanwhile, displaying the optimized track information and the position information sent by the parafoil in real time on a homing track real-time display module;
8) the event-triggered emergency algorithm functions mainly in three ways:
●, according to GPS information, attitude information (information after the attitude module is resolved), wind speed information, especially the non-ideal state of the parafoil attitude rapid change caused by the collision between parafoils, the command of free flight is rapidly made.
● when free flight command is given for a period of time, the parafoil can not stabilize the attitude due to wind and collision, and the ground control station starts the attitude adjusting module according to the change of attitude. And according to the acceleration and angular velocity information, conventional PID control is utilized, and control information is converted into a current signal for stabilizing the attitude of the parafoil unmanned aerial vehicle and is transmitted to a specific parafoil system.
●, when receiving the command that the parafoil unmanned aerial vehicle re-identifies the steering engine driving model, executing the step 2) executed by the ground control station.
The invention has the beneficial effects that:
1. the problem of complicated homing track control of a plurality of parafoil unmanned aerial vehicles is simply solved by utilizing the cooperative control of the ground control station and the parafoil unmanned aerial vehicle.
2. The whole parafoil unmanned aerial vehicle comprises a ground base station control module and a parafoil control system module. The ground base station is utilized to rapidly calculate, optimize, display, identify, solve inverse problems and other powerful functions, and the parafoil control system module is mainly responsible for data acquisition, data transmission and data reception, control instruction execution and the like sent by the ground base station.
3. And a parameter estimation method is adopted for the steering engine driving model through data information acquired by the inertial navigation unit and detection information of the current module, so that the model is closer to a real physical model.
4. The safe distance of each parafoil is considered, the cooperative control of the parafoils is considered, the centralized optimization problem of the parafoils is established, the track optimization of the single parafoil is used as the initial value of the centralized optimization, and the solution of the centralized optimization problem is accelerated.
5. The state variables x, y, z and theta and the control variable u of each parafoil unmanned aerial vehicle are subjected to orthogonal configuration, namely time dispersion, so that the homing trajectory optimization problem is converted into a nonlinear programming problem, and an optimal trajectory and an optimal control curve for programming are directly given by combining an AMPL self-contained optimization solver.
6. And according to the steering engine driving model and each optimal control curve obtained by centralized calculation, inverting to obtain the current driving variable quantity of each parafoil control system.
7. Aiming at the problem that identification models in different working conditions, sudden events and normal operation processes are not matched, a unit module based on event triggering is designed, so that the system can run healthily.
8. The parafoil unmanned aerial vehicle and the ground station are provided with rolling time domain real-time feedback control modules, and the adaptability of the parafoil unmanned aerial vehicle to various working conditions and interference is enhanced based on rolling optimization control.
Drawings
Fig. 1 is a schematic structural diagram of a single parafoil unmanned aerial vehicle of the present invention.
Fig. 2 is a schematic diagram of the system control of a plurality of parafoil drones of the present invention.
Fig. 3 is a method for orthogonally configuring state variables and control variables of a plurality of parafoil unmanned aerial vehicles according to the present invention.
Fig. 4 is an optimal trajectory curve of a plurality of parafoil unmanned planes of the present invention.
Fig. 5 is a flow chart of a plurality of parafoil unmanned aerial vehicle algorithm of the present invention.
Detailed Description
As shown in fig. 1, the structure schematic diagram of the parafoil unmanned aerial vehicle mainly comprises a left control rope 1, a right control rope 2, a parafoil 3, a steering engine and the like.
Many parafoil unmanned aerial vehicle system based on event trigger comprises ground control station and a plurality of parafoil unmanned aerial vehicle, and every parafoil unmanned aerial vehicle has the measuring transducer module, parafoil drive control module and steering wheel to and drive model detection module, parafoil drive control module makes steering wheel control rope length, and measuring transducer module measures this parafoil unmanned aerial vehicle's real-time information, and real-time information includes: acceleration information, angular velocity information, the orientation determined by the magnetometer and the length of the steering rope, and the actual drive current of the steering engine.
The ground control station is provided with a track planning module, a parafoil attitude resolving module, a parafoil attitude control module, an event emergency module, a parafoil drive identification module and a parafoil drive control inversion module; the track planning module comprises a multi-wing umbrella track homing model, a fully discrete unit for multi-wing umbrella track homing and an AMPL (amplitude modulation level) optimization unit.
The parafoil attitude calculation module receives the steering engine driving current information, the acceleration information, the angular velocity information and the control rope length information sent by the measurement sensor module and calculates the steering engine driving current information, the acceleration information, the angular velocity information and the control rope length information into corresponding parafoil unmanned aerial vehicle attitudes, sets a variation margin value of the parafoil attitude, and triggers the event emergency module when the real-time attitude variation of the parafoil unmanned aerial vehicle exceeds the variation margin value; the event emergency module enables the parafoil driving control module to stop working, and the parafoil unmanned aerial vehicle enters a free flight state.
Parafoil drive identification module for establishing steering engine drive model
Wherein
The input of driving current, u (t) the output of the length of the control rope, A the control coefficient and B the state coefficient; the parafoil driving identification module completes the determination of the control coefficient A and the state coefficient B by a parameter estimation method, andand respectively inputting the control coefficient A and the state coefficient B into a driving model detection module and a parafoil driving control module of the parafoil unmanned aerial vehicle.
Optimal control line control curve uTARInputting a parafoil drive control inversion module, solving a parafoil drive control inversion model:
an objective function of
The constraint condition is
The state is constrained to
Wherein
The minimum current is output by the parafoil driving control module,
is the maximum current output by the parafoil driving control module,
as a function of the change of the current with time, the result being a specific input value of the current with time
Specific input value of current obtained by parafoil drive control inversion model along with time
The parafoil driving control module of the input parafoil unmanned aerial vehicle.
The parafoil driving control module only needs to input a current value from a ground control station into the actuating mechanism, the actuating mechanism can enable the length of the control rope to reach a required target, and the parafoil driving control module does not need to calculate the current value which is needed by the length of the control rope and corresponds to enable the actuating mechanism to act.
The measurement sensor module continuously sends information to the parafoil attitude calculation module; after the event emergency module is triggered for a specified time, if the attitude change of the parafoil unmanned aerial vehicle still exceeds a change allowance value, the parafoil driving control module inputs the signal to the steering engine. Current signal for stabilizing attitude of parafoil unmanned aerial vehicle
The measurement sensor module comprises a current measurement module, an inertial sensing unit, a magnetometer, a GPD (general purpose display) locator and an air speed measurement module.
The ground control station is provided with a homing track real-time display module, and the homing track real-time display module displays the optimal track, the optimal control curve and the GPS position information sent by the parafoil in real time.
The algorithm of the invention comprises the following specific steps:
1. parafoil drone (measurement sensor module): the inertial sensing unit is used for measuring information such as real-time acceleration a, angular velocity w information, magnetometer, driving current and the like of the parafoil unmanned aerial vehicle, and transmitting the information to the ground control station.
2. Ground control station (parafoil attitude resolving module and parafoil drive identification module): according to the real-time acceleration a and angular velocity w information of the parafoil unmanned aerial vehicles, the quaternion method is combined to calculate the real-time parafoil attitude information, the change margin of the attitude is set, and if the parafoil attitude changes violently in a short time, an event emergency module is triggered. (see the emergency module of the incident, 11 th, 12 th step)
Because the steering engine driving model is very complicated and is a nonlinear dynamic system with strong uncertainty, the specific modeling process is very complicated and very difficult. Therefore, after the drive model of the parafoil unmanned aerial vehicle is linearized, the linearized drive model is represented by the following dynamic model (because the event trigger unit is adopted, the coefficients A and B are dynamically adjusted, so that the linearized dynamic model can infinitely approximate to a high-order nonlinear system)
In the formula (I), the compound is shown in the specification,
for current input, u (t) is the output for a particular steering cord length. A and B are respectively a control coefficient and a state coefficient, and the coefficients are unknown or have low precision after linearization, so that the coefficients of A and B are determined by adopting parameter estimation. The method comprises the following specific steps:
according to step 1, the power measurement unit records a parameter identification interval [0, T ]test]Function of internal current variation with time
Change situation, is recorded as
Record the output of the length of control rope taken in, and record
According to the output of the length of the control rope, an intelligent optimization algorithm (such as a particle swarm optimization algorithm and a neural network algorithm) is adopted to solve the minimum value
Wherein T istestTime (T) required for parameter identificationtestEmpirically determined);
according to the record
The change condition of (c) is substituted into the equation (1), and the value of u (t) is obtained by numerical solution. Then solve out
And finishing the parameter estimation of A and B through an intelligent optimization algorithm.
3. Parafoil unmanned aerial vehicle (parafoil drive control module and drive model detection module): each parafoil receives the identification parameter information sent by the ground control station, and the identification parameter information is updated and stored in the parafoil driving control module and the driving model detection module of each parafoil control unit, wherein the driving model detection module is used for matching the output of the steering engine driving model with the actual length information of the control rope. When the output of the steering engine driving model and the actual length information of the control rope have obvious inaccuracy (namely the difference value between the output of the steering engine driving model and the actual length information of the control rope exceeds a set margin value), an event driving program is triggered early. Because the operation of whole coordinated system is greatly influenced to the accuracy of drive model, consequently increase self-checking function at parafoil unmanned aerial vehicle.
4. Ground control station (multi-wing umbrella track homing modeling and control module): according to GPS position information (three-dimensional position information under earth coordinates) and wind speed information sent by each parafoil unmanned aerial vehicle
Establishing a kinematics model of a parafoil unmanned aerial vehicle
In the formula, R is the number of parafoil unmanned aerial vehicles, xr,yrZ represents the position of the r-th parafoil in the horizontal x, y and vertical z directions, respectively, in the geodetic coordinate system; v. ofrThe horizontal flying speed of the r-th parafoil is shown,
representing the horizontal wind speed, v, of the r-th parafoilzRepresenting the vertical falling speed, theta, of the parafoilrDenotes the turning angle, u, of the r-th parafoilrRepresents the control variable of the r-th parafoil. Initial conditions of the respective states are noted
(GPS information transmitted by each parafoil drone and attitude information of the parafoil).
Because each parafoil unmanned aerial vehicle needs to move in a designated area, the following restriction indexes are provided
In the formula (I), the compound is shown in the specification,
is a state variable xrThe upper and lower bounds of (a) are,
is a state variable yrThe upper and lower bounds of (a) are,
as a state variable thetarThe upper and lower bounds of (a) are,
for controlling variable urThe upper and lower bounds of (c). Since it is not possible to have multiple parafoils send collisions to each other, we also set the safe distance:
xr-xb≥xmar,yr-yb≥ymar,
r＝1,...,R，b＝1,...,R,r≠b,
wherein x ismar,ymarIs the safe distance between the parafoils.
While the desired drop point and direction are
Then our objective function is defined as
5. Ground control station (orthogonal configuration module for multi-wing umbrella track homing): in the orthogonal collocation method shown in FIG. 3, the state variables and the control variables are separated into NE sub-time intervals in the time domain (although only x is shown in the figure)r,yrBut z, thetarMay be obtained in the same manner). The time after dispersion can be expressed as t ═ tm+hmTau is more than or equal to 0 and less than or equal to 1. In each sub-time interval, the state variable xr,yr,z,θrApproximating by Lagrange polynomial to obtain
KSAre integers. Since the state variables must be continuous, we get:
similarly, in each time interval, the control variable u is approximated by a Lagrange polynomial to obtain
KUAre integers. At the same time we require that the control variables are also continuous
In FIG. 2 we use K asS＝KUTake 2 as an example.
Through an orthogonal configuration method, the state variable and the control variable are dispersed in a time domain, formulas (3) and (4) are substituted into formula (2) to obtain a kinematics dispersion equation of the parafoil unmanned aerial vehicle, and full dispersion of a dynamic model is completed.
In the formula, in the following formula,
for the actual process, the state variable xr,yr,zr,θrAnd a control variable urAre subject to the limiting conditions, and therefore, are obtained
In order to prevent the parafoil from colliding, the parafoil has a restraint
The objective function is defined as
Equations (3) - (6) thus constitute a non-linear programming problem.
6. Ground control station (AMPL optimization unit of parafoil drone): the optimization program algorithm module is as follows:
the nonlinear programming problem of homing track optimization of each parafoil unmanned aerial vehicle is solved in parallel by using a nonlinear optimization solver carried by an AMPL platform, so that each homing optimal track and an optimal control curve are obtained;
taking each homing optimal track and each optimal control curve as initial guesses of centralized optimization, and solving the homing tracks of the parafoil unmanned aerial vehicles;
and (4) verifying whether the state constraints and continuity conditions of the multiple track optimization and the safety distance between any two parafoils are met.
FIG. 4 shows the trajectory of the three parafoil controls, where the three parafoils are initiated at points
Are respectively as
The target landing point is [500,1000,0 ]]。
7. Ground control station (parafoil driven inversion model): 6, obtaining the change situation u of the length of the optimal control rope of each parafoil unmanned aerial vehicleTARAnd (3) identifying the steering engine driving model obtained according to the step (2)
Setting to optimize the control curve uTARPerformance index taking output of steering engine driving model as deviation
I.e. solving the problem
Wherein
Respectively, the minimum current and the maximum current output by the current driver. The specific input value of the current along with the time is obtained by the iterative solution of the inverse problem
Obtaining the optimal operation rope length u (t) in the step 6, obtaining a control coefficient A and a state coefficient B in the step 2, and obtaining current input through inversion calculation
8. Parafoil unmanned aerial vehicle (parafoil drive control module): each parafoil unmanned aerial vehicle receives a current input instruction and a current input value sent by the parafoil driving inversion module
Controlling the current supply to the substrateThe driving control module of the parafoil adjusts the control of the pull rope;
9. ground control station (rolling time domain real-time control module): due to the reasons of errors, working condition changes and the like of the model, the optimal running track received by the ground control station has a certain deviation with the actual running track, so that the calculation result given by the 7 th parafoil drive control inversion module is obtained
Inputting the rolling time domain real-time control module, wherein the rolling time domain real-time control module is used for controlling the fixed interval time [0, T]Is equally divided into NZSegments, each segment having a time scale of T/NZThe rolling time domain real-time control module enables the AMPL optimization unit to optimize an optimal track and an optimal control curve once in each time scale; each parafoil unmanned aerial vehicle is provided with a rolling time domain real-time feedback control module which enables the steering engine to execute only each time
[0,T/NZ]And (7) a period of time.
Then, the ground works to receive the position information and the wind speed information sent by the bottom parafoil control system in real time, and updates the position information and the wind speed information in the ground control station
And 6, displaying the optimized track information and the position information sent by the parafoil in real time on the ground control station, and simultaneously performing the 6 th to 8 th steps again, and performing rolling optimization until the parafoil safely and accurately lands.
10. Parafoil unmanned plane (rolling time domain real time control module): and receiving a rolling optimized current driving signal sent by a rolling time domain real-time control module of the ground control station, and feeding the current driving signal back to the current driving model of the parafoil. The rolling time domain real-time control module of the parafoil unmanned aerial vehicle is matched with the rolling time domain real-time control module of the ground control station, the ground control station is a command maker of the rolling control module, and the rolling time domain real-time control module of the parafoil unmanned aerial vehicle is an executor of specific rolling control.
11. Ground control station (event emergency module): the function of the event-triggered emergency module is mainly three:
according to GPS information, attitude information and wind speed information of each parafoil received in real time, especially collision between parafoils, execution error of parafoil bottom command and the like, the state of abnormality such as rapid change of parafoil attitude in a short time is caused. Setting a margin for variation of attitude in a ground control station, e.g. a margin for angular velocity variation alphaYSum acceleration variation margin wYSetting up
When the received attitude information exceeds the limit, a free flight command is rapidly sent out.
After the free flight instruction, the parafoil unmanned aerial vehicle cannot stabilize the attitude due to the influence of wind and the like, and just needs to quickly start the attitude adjusting module, control the parafoil stabilizing system by using the conventional PID according to the current acceleration alpha and angular velocity w information, solve out the parafoil current driving signal and send the parafoil current driving signal to a specific parafoil system.
And (5) receiving the re-identified steering engine driving model, executing the step 2, and sending the parameters to the parafoil unmanned aerial vehicle after identifying the parameters.
12. Parafoil drone (event emergency module):
and sending a free flight instruction, and temporarily stopping current drive input to enable the parafoil to be in a free flight state. It is very complicated to the drastic change of the posture of the parafoil. Through the free flight mode, the flight attitude can be slowed down as soon as possible. However, the situation of collision of strong wind, especially a plurality of parafoil unmanned aerial vehicles is very complicated, and the effect of the free flight mode is limited.
After receiving the command of attitude adjustment, receive corresponding current signal, drive the steering wheel, steady parafoil unmanned aerial vehicle's gesture lets parafoil unmanned aerial vehicle function safety land.
When the output of the steering engine driving model and the length information of the actual control rope are matched to exceed a certain margin value, the current and pull rope information of the parafoil unmanned aerial vehicle at present are rapidly collected and sent to a lower computer, and the steering engine driving model is identified again.
The embodiments described in this specification are merely illustrative of implementations of the inventive concept and the scope of the present invention should not be considered limited to the specific forms set forth in the embodiments but rather by the equivalents thereof as may occur to those skilled in the art upon consideration of the present inventive concept.
Claims (8)
1. Many parafoil unmanned aerial vehicle system based on event trigger comprises ground control station and a plurality of parafoil unmanned aerial vehicle, and every parafoil unmanned aerial vehicle has the measuring transducer module, parafoil drive control module and steering wheel, and parafoil drive control module makes steering wheel control rope length, and the measuring transducer module measures this parafoil unmanned aerial vehicle's real-time information, and real-time information includes: acceleration information, angular velocity information, orientation determined by the magnetometer and length of the steering rope; the ground control station is provided with a track planning module; the method is characterized in that: the real-time information comprises the actual driving current of the steering engine;
the ground control station is provided with a parafoil attitude resolving module, a parafoil attitude control module, an event emergency module, a parafoil drive identification module and a parafoil drive control inversion module; the parafoil unmanned aerial vehicle is provided with a driving model detection module;
the parafoil attitude calculation module receives the steering engine driving current information, the acceleration information, the angular velocity information and the control rope length information sent by the measurement sensor module and calculates the steering engine driving current information, the acceleration information, the angular velocity information and the control rope length information into corresponding parafoil unmanned aerial vehicle attitudes, sets a variation margin value of the parafoil attitude, and triggers the event emergency module when the real-time attitude variation of the parafoil unmanned aerial vehicle exceeds the variation margin value; the event emergency module enables the parafoil driving control module to stop working, and the parafoil unmanned aerial vehicle enters a free flight state;
parafoil drive identification module for establishing steering engine drive model
Wherein
The input of driving current, u (t) the output of the length of the control rope, A the control coefficient and B the state coefficient; the parafoil driving identification module completes the determination of a control coefficient A and a state coefficient B by a parameter estimation method, and inputs the control coefficient A and the state coefficient B into a driving model detection module and a parafoil driving control module of the parafoil unmanned aerial vehicle respectively;
optimal control line control curve uTARInputting a parafoil drive control inversion module, solving a parafoil drive control inversion model:
an objective function of
The constraint condition is
The state is constrained to
Wherein
The minimum current is output by the parafoil driving control module,
is the maximum current output by the parafoil driving control module,
as a function of the change of the current with time, the result being a specific input value of the current with time
Specific input value of current obtained by parafoil drive control inversion model along with time
The parafoil driving control module of the input parafoil unmanned aerial vehicle.
2. The event-trigger-based multi-parachute drone system of claim 1, wherein: when the event emergency module is triggered, the measurement sensor module continuously sends information to the parafoil attitude calculation module; after the event emergency module is triggered for a specified time, if the attitude change of the parafoil unmanned aerial vehicle still exceeds a change allowance value, the parafoil driving control module inputs the change allowance value to the steering engine
Is the specific input value of the current over time.
3. The event-trigger-based multi-parachute drone system of claim 2, wherein: the measurement sensor module comprises a current measurement module, an inertial sensing unit, a magnetometer, a GPD (general purpose display) locator and an air speed measurement module.
4. The event-trigger-based multi-parachute drone system of claim 3, wherein: the process of determining the control coefficient A and the state coefficient B by the parafoil driving identification module comprises the following steps:
step 1: parameter identification interval [0, T ] recorded by current measurement module of parafoil receiving unmanned aerial vehicletest]Function of current change with time
Is recorded as
Step 2: recording the output of the length of the control rope, note
And step 3:solving for the minimum
Wherein T istestTime required for parameter identification;
and 4, step 4: will be provided with
Bringing in
Obtaining u (t) by numerical solution, and then solving
And then, finishing the estimation of the coefficients A and B by an intelligent optimization algorithm.
5. The event-trigger-based multi-parachute drone system of claim 4, wherein: the driving model detection module judges whether the output of the steering engine driving model is matched with the length information of the actual control rope, and when the output of the steering engine driving model is obviously not matched with the length information of the actual control rope, the driving model detection module triggers the event emergency module and transmits the real-time current of the driving control module and the length information of the current control rope to the ground control station; an obvious mismatch is that the difference between the actual steering rope length and the output of the steering engine drive model is greater than a set margin value.
6. The event-trigger-based multi-parachute drone system of claim 5, wherein: the track planning module comprises a multi-wing umbrella track homing model, a fully discrete unit for multi-wing umbrella track homing and an AMPL (amplitude modulation level) optimization unit;
in the multi-wing umbrella track homing model, the kinematics model of the wing umbrella unmanned aerial vehicle is as follows:
wherein R is the total number of parafoil unmanned aerial vehicles, xr,yrAnd z represents the coordinate of the r-th parafoil unmanned aerial vehicle in a geodetic coordinate system, vrRepresents the horizontal flying speed of the r-th parafoil unmanned plane,
represents the horizontal wind speed measured by the r-th parafoil unmanned plane, vzIndicating the vertical drop velocity, theta, of the parafoil dronerIndicates the turning angle u of the r-th parafoil unmanned planerThe length of a control rope of the r-th parafoil unmanned aerial vehicle is shown;
the limiting conditions of the motion area of each parafoil unmanned aerial vehicle are as follows:
safe distance x between parafoil unmanned aerial vehiclesmar,ymarThe following settings are set:
xr-xb≥xmar,yr-yb≥ymar；r＝1,2,...,R；b＝1,2,...,R；r≠b；
with the coordinates of the desired drop point and the turning angle as
The objective function is:
full discrete unit of multi-wing umbrella track homing will xr,yr,z,θr,urIn the time domain, NE sub-time intervals are separated, and the separated time is expressed as t ═ tm+hmτ, in each sub-time interval, the state variable is represented as:
ks is an integer;
the continuity conditions that the state variables must satisfy are:
the control variable is expressed as
KUIs an integer;
the continuity conditions that the control variables must satisfy are:
only in the continuity condition, m ═ 1, 2., NE-1;
the fully discrete kinematic equation is:
in the formula:
the constraint is fully discrete as:
the safe distance is fully discrete as:
the objective function of the fully discrete trajectory homing model is:
the AMPL optimization unit optimizes and solves a fully discrete track homing model and an objective function thereof to obtain an optimal track and an optimal control curve of each parafoil unmanned aerial vehicle; solving the homing tracks of the parafoil unmanned aerial vehicles by taking the optimal track and the optimal control curve of each parafoil unmanned aerial vehicle as initial guesses of centralized optimization; verifying whether the verified homing track meets the constraint of the state variable, the continuity condition and the safety distance between any two parafoil unmanned aerial vehicles; if so, inputting the optimal track and the optimal control curve into a parafoil drive control inversion module; if not, the optimal track and the optimal control curve are calculated again.
7. The event-trigger-based multi-parachute drone system of claim 6, wherein: the measurement sensor module of each parafoil unmanned aerial vehicle sends real-time information to the parafoil attitude calculation module; the ground control station is provided with a rolling time domain real-time control module and a parafoil drive control inversion module
Inputting the rolling time domain real-time control module, wherein the rolling time domain real-time control module is used for controlling the fixed interval time [0, T]Is equally divided into NZSegments, each segment having a time scale of T/NZThe rolling time domain real-time control module enables the AMPL optimization unit to optimize an optimal track and an optimal control curve once in each time scale; each parafoil unmanned aerial vehicle is provided with a rolling time domain real-time feedback control module which enables the steering engine to execute only each time
[0,T/NZ]And (7) a period of time.
8. The event-trigger-based multi-parachute drone system of claim 7, wherein: the ground control station is provided with a homing track real-time display module which displays the optimal track, the optimal control curve and the GPS position information sent by the parafoil in real time.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710783381.9A CN107608366B (en) | 2017-09-01 | 2017-09-01 | Multi-wing umbrella unmanned aerial vehicle system based on event trigger |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710783381.9A CN107608366B (en) | 2017-09-01 | 2017-09-01 | Multi-wing umbrella unmanned aerial vehicle system based on event trigger |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN107608366A CN107608366A (en) | 2018-01-19 |
| CN107608366B true CN107608366B (en) | 2021-02-05 |
Family
ID=61057246
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201710783381.9A Active CN107608366B (en) | 2017-09-01 | 2017-09-01 | Multi-wing umbrella unmanned aerial vehicle system based on event trigger |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN107608366B (en) |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109471448A (en) * | 2018-12-27 | 2019-03-15 | 西北工业大学 | One kind being based on event driven flexible spacecraft attitude control method |
| CN111413996B (en) * | 2020-04-09 | 2023-03-21 | 中北大学 | Four-rotor performance-guaranteeing trajectory tracking control method based on event-triggered ESO |
| CN112182957B (en) * | 2020-09-15 | 2022-05-03 | 西北工业大学 | One-sub umbrella-control recovery flight path planning method based on longicorn group algorithm |
| CN112270103B (en) * | 2020-11-09 | 2023-04-11 | 北京理工大学重庆创新中心 | Cooperative strategy inversion identification method based on multi-agent game |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103101621A (en) * | 2013-01-22 | 2013-05-15 | 北京航空航天大学 | Parafoil aircraft applicable to cylindrical space loading |
| CN105404308A (en) * | 2015-11-24 | 2016-03-16 | 中国电子科技集团公司第二十七研究所 | Flight control unit for parafoil type unmanned plane |
| CN106347675A (en) * | 2016-10-17 | 2017-01-25 | 大连理工大学 | Remote control parachute |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6758442B2 (en) * | 2002-10-30 | 2004-07-06 | Stara Technologies, Inc. | Guided parafoil system for delivering lightweight payloads |
-
2017
- 2017-09-01 CN CN201710783381.9A patent/CN107608366B/en active Active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103101621A (en) * | 2013-01-22 | 2013-05-15 | 北京航空航天大学 | Parafoil aircraft applicable to cylindrical space loading |
| CN105404308A (en) * | 2015-11-24 | 2016-03-16 | 中国电子科技集团公司第二十七研究所 | Flight control unit for parafoil type unmanned plane |
| CN106347675A (en) * | 2016-10-17 | 2017-01-25 | 大连理工大学 | Remote control parachute |
Non-Patent Citations (1)
| Title |
|---|
| "风筝发电机翼伞姿态控制方法的研究";贺建平;《中国优秀硕士学位论文全文数据库 工程科技II辑》;20081015(第10期);全文 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN107608366A (en) | 2018-01-19 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN107608366B (en) | Multi-wing umbrella unmanned aerial vehicle system based on event trigger | |
| CN108873929B (en) | Method and system for autonomous landing of fixed-wing aircraft | |
| Stastny et al. | Nonlinear model predictive guidance for fixed-wing UAVs using identified control augmented dynamics | |
| US11060658B2 (en) | Gimbal stabilization system and method | |
| Lei et al. | A linear domain system identification for small unmanned aerial rotorcraft based on adaptive genetic algorithm | |
| JP2011246105A (en) | Wind estimation for unmanned aerial vehicle | |
| Iwaneczko et al. | A prototype of unmanned aerial vehicle for image acquisition | |
| Pappu et al. | Wind gust estimation on a small VTOL UAV | |
| Amelin et al. | Recursive identification of motion model parameters for ultralight UAV | |
| Wang et al. | Autonomous control for micro-flying robot and small wireless helicopter xrb | |
| Setyawan et al. | Linear quadratic regulator controller (LQR) for AR. Drone's safe landing | |
| Kimmett et al. | Vision based controller for autonomous aerial refueling | |
| Sandino et al. | First experimental results on enhancing hovering performance of unmanned helicopters by using a tethered setup | |
| CN104391364B (en) | Coaxial double-rotary wing depopulated helicopter parameter identification pilot system based on fiber cable laying | |
| Saderla et al. | Parameter estimation of UAV from flight data using neural network | |
| Gim et al. | Longitudinal system identification of ornithopter with automated flight tests | |
| Wang et al. | Autonomous control of micro flying robot | |
| Czyba et al. | Model identification and data fusion for the purpose of the altitude control of the VTOL aerial robot | |
| Tang et al. | Homing on a moving dock for a quadrotor vehicle | |
| Quinlan et al. | Technical Challenges Associated with In-Air Wingtip Docking of Aircraft in Forward Flight | |
| Trizuljak et al. | Control of a small quadrotor for swarm operation | |
| Rose et al. | Development and validation of flight dynamics model of a uav airplane | |
| Jimenez et al. | Experimental validation of Unmanned Aerial Vehicles to tune PID controllers in open source autopilots | |
| Kumar et al. | System Identification, HIL and Flight Testing of an Adaptive Controller on a Small Scale Unmanned Aircraft | |
| Müller et al. | Cascaded Indoor Flight Controller Design for a Miniaturized Tiltwing Aircraft |
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 |