阅读说明：本技术 复合式无人机半实物仿真系统 (Combined type unmanned aerial vehicle semi-physical simulation system ) 是由 王松 胡豫锦 阿娜斯塔 付仁皓 张楠 于 2020-05-26 设计创作，主要内容包括：本发明公开了复合式无人机半实物仿真系统,属于系统仿真技术领域。该系统包括数学模型、三轴转台、缩比样机、三维视景模块、飞行数据监测模块和飞行控制模块。首先建立真实无人机A的仿真数学模型,将无人机A的状态量输入到飞行控制模块中,解算出控制量驱动无人机A舵面和电机油门进行动作,并将姿态角数据和控制数据分别传递给三轴转台的单片机,驱动三轴转台运动带动缩比样机,实现三自由度的姿态运动展示,以及舵量、四旋翼电机和固定翼电机的油门展示。飞行数据监测模块实时监测状态量,并绘制成曲线显示。通过将无人机A的状态量递给三维视景模块,从而实现模型无人机A起降的全流程视景展示。本发明控制成本,提高效率,实现人机交互。(The invention discloses a combined type unmanned aerial vehicle semi-physical simulation system, and belongs to the technical field of system simulation. The system comprises a mathematical model, a three-axis rotary table, a scaling model machine, a three-dimensional view module, a flight data monitoring module and a flight control module. Firstly, a simulation mathematical model of a real unmanned aerial vehicle A is established, the state quantity of the unmanned aerial vehicle A is input into a flight control module, the control quantity is solved to drive a control surface of the unmanned aerial vehicle A and a motor throttle to move, attitude angle data and control data are respectively transmitted to a single chip microcomputer of a three-axis turntable, the three-axis turntable is driven to move to drive a scaling model machine, and three-degree-of-freedom attitude motion display and throttle display of a rudder quantity, a four-rotor motor and a fixed wing motor are realized. And the flight data monitoring module monitors the state quantity in real time and draws a curve to display. The state quantity of the unmanned aerial vehicle A is delivered to the three-dimensional view module, so that the full-flow view display of the take-off and landing of the model unmanned aerial vehicle A is realized. The invention controls the cost, improves the efficiency and realizes the human-computer interaction.)

1. Combined type unmanned aerial vehicle semi-physical simulation system, its characterized in that includes: the system comprises a mathematical model, a three-axis rotary table, a scaling model machine, a three-dimensional view module, a flight data monitoring module, a flight control module, a ground station and a communication module among all parts;

the system comprises a mathematical model, a three-dimensional view module, a flight data monitoring module and a ground station, wherein the mathematical model, the three-dimensional view module, the flight data monitoring module and the ground station operate in a PC; the three-axis rotary table, the scaling prototype and the flight control module are real objects; data transmission between the composite unmanned aerial vehicle mathematical model and the flight control module is realized through one path of serial port communication; the data communication between the mathematical model of the combined unmanned aerial vehicle and the three-axis rotary table is realized through the serial port communication of the other path; the compound unmanned aerial vehicle scaling model machine is placed on a three-axis rotary table, and the output signal of the three-axis rotary table controls the movement of a motor and a control surface in the compound unmanned aerial vehicle scaling model machine;

the composite unmanned aerial vehicle mathematical model is a simulated mathematical model obtained after simulation modeling is carried out on a real unmanned aerial vehicle A in a PC (personal computer), and the simulated mathematical model comprises a motor module, an aerodynamic force and moment resolving module and a six-degree-of-freedom motion equation module and is mainly used for completing the attitude and position resolving of the model unmanned aerial vehicle A;

inputting the position, attitude and speed state information of the model unmanned aerial vehicle A into a flight control module, and resolving through a control law in the flight control module to obtain the rudder amount, the fixed wing motor throttle and the four-rotor motor throttle of the current state of the model unmanned aerial vehicle A;

the flight control module feeds the control quantities back to a motor module and a pneumatic force and moment resolving module in the simulation mathematical model again to resolve the force and the moment, and inputs the force and the moment into a six-degree-of-freedom motion equation module to resolve to obtain the attitude, the position, the speed and the acceleration of the model unmanned aerial vehicle A, so that closed-loop communication is formed;

the three-axis rotary table is used for realizing physical display of the attitude motion of the model unmanned aerial vehicle A, and can perform motion with three degrees of freedom, namely pitching motion, rolling motion and yawing motion, by means of three serially connected motion frames; the three-axis turntable comprises a steering engine, an angle sensor and a single chip microcomputer; the steering engine is used as a driver, the angle sensor is used as an attitude measurer, and the single chip microcomputer is used as a controller;

the scaling model machine is fixed above the three-axis rotary table, and the change of the attitude angle of the scaling model machine is realized by driving the scaling model machine by means of the movement of the three-axis rotary table; the single chip microcomputer simultaneously receives the rudder quantity sent by the mathematical model, the four-rotor motor accelerator and the fixed wing motor accelerator, controls deflection of a control surface in the scaling model machine and rotation of the four-rotor motor and the fixed wing motor, and keeps the dynamic of the scaling model machine the same as the dynamic of the simulation operation of the model unmanned aerial vehicle A in the PC.

2. The hybrid unmanned aerial vehicle semi-physical simulation system of claim 1, wherein the three tandem motion frames comprise: the pitching motion frame, the rolling motion frame and the yawing motion frame are in a half I shape; a slip ring is adopted for transmitting PWM signals; the single-chip microcomputer is used as a controller, three attitude angle signals of the model unmanned aerial vehicle A sent by the mathematical model are received, PWM (pulse-width modulation) waves are output according to a certain rule through the function of a timer in the single-chip microcomputer to control a steering engine to drive three serially-connected motion frames, the motion of the rotary table is realized, and meanwhile, an angle sensor is used for measuring the attitude angle of the three-axis rotary table.

3. The semi-physical simulation system of the composite unmanned aerial vehicle as claimed in claim 1, wherein the flight data monitoring module collects and displays the attitude angle, attitude angular velocity, longitude and latitude and altitude information of the model unmanned aerial vehicle a during operation, rapidly judges the current operation state of the model unmanned aerial vehicle a, marks the abnormal flight data and corresponding time during the flight process, and plays back the previous flight data.

4. The semi-physical simulation system of the composite unmanned aerial vehicle as claimed in claim 1, wherein the three-dimensional view module is used to show the full flight of the model unmanned aerial vehicle a, the three-dimensional model of the unmanned aerial vehicle a built by 3D modeling in the PC is imported into the three-dimensional view module, the corresponding structure in the three-dimensional model is driven to move by inputting the actions of three control surfaces of the aileron, the rudder and the elevator of the model unmanned aerial vehicle a, the fixed wing motor and the quad rotor motor, and the position and the attitude of the three-dimensional model in the three-dimensional view module are changed by inputting the longitude and latitude, the height and the attitude, so as to realize the three-dimensional simulated flight of the model unmanned aerial vehicle a.

5. The hybrid unmanned aerial vehicle semi-physical simulation system of claim 1, wherein the specific simulation method comprises the following steps:

step one, establishing a simulation mathematical model aiming at the composite unmanned aerial vehicle A in MATLAB/Simulink software;

the simulation mathematical model comprises a motor module, a pneumatic force and moment resolving module and a six-degree-of-freedom motion equation module;

the mathematical modeling equation of the motor module in the frequency domain is as follows:

ω represents the motor speed, C_RThe curve coefficient of the motor is represented, the throttle of the motor is represented, and the value is between 0 and 1, omega_bRepresenting the motor curve constant, T_mRepresenting a motor response time constant, and s represents a differential term in a frequency domain;

F＝C_t*ω*ω

f denotes the force generated by a single motor, C_tRepresenting the single-oar tension coefficient;

the inputs of the aerodynamic force and moment calculation module are an attack angle α, a sideslip angle β and an elevator deflection angle of the aircraft_eAileron declination angle_aRudder deflection angle_rThe output is aerodynamic force and aerodynamic moment;

the aerodynamic and moment equations are as follows:

the aerodynamic forces acting on the aircraft are split into a drag D, a lift L and lateral forces C, C_DIs the coefficient of resistance, C_CIs the lateral force coefficient, L is the lift coefficient, ρ is the air density, V is the flight speed, S is the reference area of the aircraft;

the aerodynamic moment is decomposed into a roll moment L_rollPitching moment M, yawing moment N, C_lIs the roll moment coefficient, C_mIs the coefficient of pitching moment, C_nIs the yaw moment coefficient, b is the wing span length, C_AIs the average aerodynamic chord length of the airfoil;

the six-degree-of-freedom motion equation is as follows:

centroid kinetic equation:

(u, v, w) represents the x, y, z axis velocity components in the body coordinate system,representing the speed change rate of x, y and z axes in a body coordinate system, wherein (p, q and r) are angular speed components of the x, y and z axes in the body coordinate system; (phi, theta, psi) is a coordinate system of the bodyRoll angle, pitch angle and yaw angle of the middle x, y and z axes; g represents the acceleration of gravity, m represents the mass of the drone, F_x，F_y，F_zRepresenting the components of the combined external force received by the unmanned aerial vehicle in a body coordinate system x, y and z;

equation of rotational dynamics:

(I_x，I_y，I_z) Is the moment of inertia of the aircraft about the x, y, z axes, I_zxIs the product of inertia of the aircraft about the zx axis;

centroid kinematics equation:

representing the change rate of the three-axis position of the aircraft in a terrestrial coordinate system;

rotational kinematic equation:

wherein the content of the first and second substances,the roll angle change rate, the pitch angle change rate and the yaw angle change rate;

inputting the state quantity of the model unmanned aerial vehicle A into a flight control module through a serial port communication module, resolving out a control quantity through a control law, and driving a control plane and a motor throttle of the model unmanned aerial vehicle A to act;

the state quantity comprises the position, the attitude, the speed and the acceleration of the model unmanned aerial vehicle A;

thirdly, transmitting attitude angle data in the movement process of the model unmanned aerial vehicle A to a single chip microcomputer of a three-axis turntable through a serial port communication module, controlling a steering engine to drive a pitching movement frame, a rolling movement frame and a yawing movement frame which are connected in series to move by the single chip microcomputer, further driving a scaling sample machine, and realizing attitude movement display of three degrees of freedom, namely pitching, rolling and yawing, of the scaling sample machine;

transmitting control data in the motion process of the model unmanned aerial vehicle A to a single chip microcomputer of a three-axis turntable through a serial port communication module, outputting a control signal by the single chip microcomputer to control the deflection of a control surface of a scaling model machine, and displaying the rudder amount of the model unmanned aerial vehicle A and the sizes of the four rotor motors and the accelerator of the fixed wing motor by the rotation of the four rotor motors and the fixed wing motor;

step five, a flight data monitoring module monitors the position, the attitude, the speed, the deflection angle of a control plane, the throttle of a fixed wing motor and the rotating speed state quantity of a four-rotor motor of the model unmanned aerial vehicle A in the flight process in real time, draws curve changes and displays real-time state quantity data;

and step six, transmitting control surface motion, longitude and latitude, height, speed and pitch angle information of the model unmanned aerial vehicle A to the three-dimensional visual module through UDP communication, thereby realizing the full-flow visual display of the take-off and landing of the model unmanned aerial vehicle A.

6. The semi-physical simulation system of the composite unmanned aerial vehicle of claim 5, wherein the control law design in the second step comprises control law design in a quadrotor mode, control law design in a fixed wing mode and control law design in a transition mode;

for a four-rotor mode, the control law design comprises longitudinal outer ring height control-inner ring pitch angle control; course outer ring course distance/speed control-inner ring course angle control; transverse distance/speed control of the transverse outer ring-roll angle control of the inner ring;

for the fixed wing mode, the control law design comprises longitudinal outer ring height-inner ring pitch angle control; course horizontal position/course control; controlling lateral deviation distance of the transverse outer ring and roll angle of the inner ring; and airspeed control;

and for the control of the transition mode, carrying out certain combination on the control law of the four-rotor mode and the control law of the fixed wing mode according to the control requirement to obtain the control of the transition mode.

7. The semi-physical simulation system of composite unmanned aerial vehicle of claim 5, wherein the control data in step four includes rudder amount, four-rotor motor throttle and fixed-wing motor throttle.

Technical Field

The invention belongs to the technical field of system simulation, and particularly relates to a combined type unmanned aerial vehicle semi-physical simulation system.

Background

The combined type unmanned aerial vehicle is an aircraft with vertical take-off and landing capability and has a novel structure which is widely concerned in recent years, the aircraft with the structure is obtained by simply combining a fixed wing aircraft and a four-rotor suite, and the combined type unmanned aerial vehicle has the advantages of low technical realization threshold, low cost and the like.

In the development of the aircraft, simulation is an indispensable supporting means, and the simulation has extremely important effects on improving the design quality of the aircraft, reducing the development cost and shortening the development period. According to statistics, the simulation technology can shorten the aircraft development cycle by 20-40%, save the number of the shaping test samples by 10-30%, reduce the test times by 50-80%, and shorten the joint debugging time by 40-60%.

Semi-physical simulation is a branch of simulation technology, is a simulation mode combining computer software, a mathematical model, system components (or equipment) and a physical effect device (or simulator), and is an essential main simulation method and means for complex engineering systems including aircrafts. The semi-physical simulation technology can realize human and hardware in-loop simulation, and the simulation fidelity and reliability are relatively high, so that the simulation technology is of great importance to aircraft development.

In recent years, rapid prototyping method design is gradually popular in the aspects of aircraft simulation at home and abroad. The rapid prototyping is to establish a system model for a flight control system and an unmanned aerial vehicle by using a Matlab/Simulink module block diagram to carry out full-digital simulation design. And then, directly generating an optimized and portable embedded Real-Time code from the Simulink module by using an RTW (Real-Time Workshop), and downloading the optimized and portable embedded Real-Time code to an embedded computer provided with a Vxworks or RTX Real-Time operating system for simulation.

At present, designs of semi-physical simulation systems aiming at conventional fixed wings and four rotors are not few, but designs of the semi-physical simulation systems aiming at the composite unmanned aerial vehicle are relatively lack. The combined type unmanned aerial vehicle adopts the fixed wing and rotor wing composite design, carries two sets of driving systems of the fixed wing driving system and the four-rotor wing driving system, and has the advantages of high feasibility, simple mechanical structure, low economic cost, high safety factor and the like. The working principle is that the four-rotor-wing aircraft flies according to a four-rotor mode in a vertical take-off and landing stage and a low-speed stage, and a propeller is driven to rotate through the rotation of a motor, so that pulling force required by the flight is generated; and in a high-speed state, the mode is switched to a fixed wing mode for flying, the aerodynamic lift force generated by the wing surface of the wing overcomes the gravity, and the thrust generated by the thrust engine overcomes the aerodynamic resistance to realize flying.

The composite unmanned aerial vehicle semi-physical simulation system is built, development cost can be effectively reduced, verification of flight control laws, parameter selection and the like are completed in the semi-physical simulation system, especially design and verification of the control laws in a transition stage can reduce test flight risks before outfield flight, faults and problems which possibly occur in the flight process can be simulated and solved through a ground simulation system experiment as far as possible, and therefore the composite unmanned aerial vehicle semi-physical simulation system is necessary to design.

In the prior document 1, a model of an unmanned aerial vehicle avionics semi-physical simulation system with publication number CN108008646A is established, which includes flight simulation, three-dimensional view, an interface, a simulation console and the like, but the scheme is directed to an unmanned helicopter and does not have dynamic display of a physical turntable and a scaling model machine and data monitoring and display in the flight simulation process. In document 2, "a visual unmanned aerial vehicle flight control semi-physical simulation test method and system" with publication number CN102789171A establishes an unmanned aerial vehicle system dynamics model and a three-dimensional simulation model for driving an unmanned aerial vehicle. But this solution does not describe which type of drone it is directed to, and again lacks the dynamic presentation of the physical turret and scaling prototypes.

Disclosure of Invention

Aiming at the problems, the invention provides a set of semi-physical simulation system aiming at a composite unmanned aerial vehicle. The method comprises the steps of solving the attitude and position of the unmanned aerial vehicle by establishing a composite unmanned aerial vehicle mathematical model, and outputting information such as an attitude angle, a position, a speed and an acceleration of the unmanned aerial vehicle; flight path planning and flight attitude control are carried out through a flight control module, and control quantities such as rudder quantity, an accelerator of a fixed wing motor and a four-rotor motor are output; designing a physical three-axis turntable to show the attitude change of the composite unmanned aerial vehicle; designing a scaling model machine of the composite unmanned aerial vehicle to show the actions of a control surface, a four-rotor motor and a fixed-wing motor of the composite unmanned aerial vehicle; designing a flight data monitoring module to monitor the change of the state quantity of the mathematical model of the unmanned aerial vehicle in the simulation process; the three-dimensional visual module is designed to realize visual display of full-flow simulation vertical take-off, mode switching, hovering and vertical landing flight of the digital airplane, so that the design and the construction of the semi-physical simulation system of the composite unmanned aerial vehicle are realized.

The combined type unmanned aerial vehicle semi-physical simulation system comprises: the system comprises a mathematical model, a three-axis rotary table, a scaling model machine, a three-dimensional view module, a flight data monitoring module, a flight control module, a ground station and a communication module among all parts.

The system comprises a mathematical model, a three-dimensional view module, a flight data monitoring module and a ground station, wherein the mathematical model, the three-dimensional view module, the flight data monitoring module and the ground station operate in a PC; the three-axis rotary table, the scaling prototype and the flight control module are real objects. Data transmission between the composite unmanned aerial vehicle mathematical model and the flight control module is realized through one path of serial port communication; the data communication between the mathematical model of the combined unmanned aerial vehicle and the three-axis rotary table is realized through the serial port communication of the other path; the compound unmanned aerial vehicle scaling model machine is placed on the three-axis rotary table, and the output signal of the three-axis rotary table controls the movement of the motor and the control surface in the compound unmanned aerial vehicle scaling model machine.

The combined type unmanned aerial vehicle mathematical model is a simulated mathematical model obtained after simulation modeling is carried out on a real unmanned aerial vehicle A in a PC (personal computer), and the simulated mathematical model comprises a motor module, an aerodynamic force and moment resolving module and a six-degree-of-freedom motion equation module and is mainly used for completing the attitude and position resolving of the model unmanned aerial vehicle A.

Inputting state information such as the position, the attitude, the speed and the like of the model unmanned aerial vehicle A into a flight control module, and resolving the state information by a control law in the flight control module to obtain control quantities such as a rudder quantity, a fixed wing motor accelerator, a four-rotor motor accelerator and the like of the current state of the model unmanned aerial vehicle A;

the flight control module feeds the control quantities back to a motor module and a pneumatic force and moment resolving module in the simulation mathematical model again to resolve the force and the moment, and inputs the force and the moment into a six-degree-of-freedom motion equation module to resolve to obtain information such as the attitude, the position, the speed and the acceleration of the model unmanned aerial vehicle A, so that closed-loop communication is formed;

the three-axis rotary table is used for realizing physical display of the A attitude motion of the model unmanned aerial vehicle, and the three-axis rotary table can perform motion with three degrees of freedom, namely pitching motion, rolling motion and yawing motion, by means of three serially connected motion frames. The three-axis turntable comprises a steering engine, an angle sensor and a single chip microcomputer; the steering engine is used as a driver, the angle sensor is used as an attitude measurer, and the single chip microcomputer is used as a controller.

Three serially connected moving frames include: the pitching motion frame, the rolling motion frame and the yawing motion frame are in a half I shape; a slip ring is adopted for transmitting PWM signals; the single-chip microcomputer is used as a controller, three attitude angle signals of the model unmanned aerial vehicle A sent by the mathematical model are received, PWM (pulse-width modulation) waves are output according to a certain rule through the function of a timer in the single-chip microcomputer to control a steering engine to drive three serially-connected motion frames, the motion of the rotary table is realized, and meanwhile, an angle sensor is used for measuring the attitude angle of the three-axis rotary table.

The scaling model machine is fixed above the three-axis rotary table, and the change of the attitude angle of the scaling model machine is realized by driving the scaling model machine by means of the movement of the three-axis rotary table; the single chip microcomputer receives control signals of a rudder amount, a four-rotor motor accelerator, a fixed wing motor accelerator and the like sent by the mathematical model at the same time, controls deflection of a control plane in the scaling model machine and rotation of the four-rotor motor and the fixed wing motor, and keeps the dynamic of the scaling model machine the same as the dynamic of simulation operation of the model unmanned aerial vehicle A in the PC.

The flight data monitoring module is used for acquiring and displaying information such as attitude angle, attitude angular velocity, longitude and latitude, height and the like of the model unmanned aerial vehicle A in the operation process in a curve mode, rapidly judging the current operation state of the model unmanned aerial vehicle A, marking abnormal flight data and corresponding time in the flight process and playing back the previous flight data.

The three-dimensional view module is used for displaying the full-flow flight of the model unmanned aerial vehicle A, a three-dimensional model of the unmanned aerial vehicle A is built in a PC through 3D modeling and is led into the three-dimensional view module, corresponding structures in the three-dimensional model are driven to move through the actions of an aileron, a rudder and an elevator of the model unmanned aerial vehicle A, a fixed wing motor and a four-rotor motor, and the position and the posture of the three-dimensional model in the three-dimensional view module are changed through inputting longitude and latitude, height and posture, so that the three-dimensional simulated flight of the model unmanned aerial vehicle A is realized.

The combined type unmanned aerial vehicle semi-physical simulation method specifically comprises the following steps:

step one, establishing a simulation mathematical model aiming at the composite unmanned aerial vehicle A in MATLAB/Simulink software;

the simulation mathematical model comprises a motor module, a pneumatic force and moment resolving module and a six-degree-of-freedom motion equation module;

the mathematical modeling equation of the motor module in the frequency domain is as follows:

ω represents the motor speed, C_RThe curve coefficient of the motor is represented, the throttle of the motor is represented, and the value is between 0 and 1, omega_bRepresenting the motor curve constant, T_mDenotes the motor response time constant and s denotes the differential term in the frequency domain.

F＝C_t*ω*ω

F denotes the force generated by a single motor, C_tRepresenting the single-paddle coefficient of tension.

The inputs of the aerodynamic force and moment calculation module are an attack angle α, a sideslip angle β and an elevator deflection angle of the aircraft_eAileron declination angle_aRudder deflection angle_rThe output is aerodynamic force and aerodynamic moment.

The aerodynamic and moment equations are as follows:

the aerodynamic forces acting on the aircraft are split into a drag D, a lift L and lateral forces C, C_DIs the coefficient of resistance, C_CIs the lateral force coefficient, L is the lift coefficient, ρ is the air density, V is the flight speed, S is the reference area of the aircraft;

the aerodynamic moment is decomposed into a roll moment L_rollPitching moment M, yawing moment N, C_lIs the roll moment coefficient, C_mIs the coefficient of pitching moment, C_nIs the yaw moment coefficient, b is the wing span length, C_AIs the average aerodynamic chord length of the wing.

The six-degree-of-freedom motion equation is as follows:

centroid kinetic equation:

(u, v, w) represents the x, y, z axis velocity components in the body coordinate system,the variable rate of the speed of the x, y and z axes in the body coordinate system is shown, and (p, q and r) are the angular speed components of the x, y and z axes in the body coordinate system. And (phi, theta, psi) are rolling angles, pitching angles and yaw angles of x, y and z axes in a body coordinate system. g represents the acceleration of gravity, m represents the mass of the drone, F_x,F_y,F_zRepresenting the components of the combined external force received by the unmanned aerial vehicle in a body coordinate system x, y and z;

equation of rotational dynamics:

(I_x,I_y,I_z) The moment of inertia of the aircraft about the x, y, z axes,I_zxis the product of inertia of the aircraft about the zx axis;

centroid kinematics equation:

representing the rate of change of the three-axis position of the aircraft in the terrestrial coordinate system.

Rotational kinematic equation:

wherein the content of the first and second substances,the roll angle change rate, the pitch angle change rate and the yaw angle change rate;

inputting the state quantity of the model unmanned aerial vehicle A into a flight control module through a serial port communication module, resolving out a control quantity through a control law, and driving a control plane and a motor throttle of the model unmanned aerial vehicle A to act;

the state quantity comprises the position, the posture, the speed, the acceleration and the like of the model unmanned aerial vehicle A;

the control law design comprises control law design under a four-rotor mode, control law design under a fixed wing mode and control law design under a transition mode.

For a four-rotor mode, the control law design comprises longitudinal outer ring height control-inner ring pitch angle control; course outer ring course distance/speed control-inner ring course angle control; lateral outer ring lateral distance/velocity control-inner ring roll angle control.

For the fixed wing mode, the control law design comprises longitudinal outer ring height-inner ring pitch angle control; course horizontal position/course control; controlling lateral deviation distance of the transverse outer ring and roll angle of the inner ring; and airspeed control.

And for the control of the transition mode, carrying out certain combination on the control law of the four-rotor mode and the control law of the fixed wing mode according to the control requirement to obtain the control of the transition mode.

Thirdly, transmitting attitude angle data in the movement process of the model unmanned aerial vehicle A to a single chip microcomputer of a three-axis turntable through a serial port communication module, controlling a steering engine to drive a pitching movement frame, a rolling movement frame and a yawing movement frame which are connected in series to move by the single chip microcomputer, further driving a scaling sample machine, and realizing attitude movement display of three degrees of freedom, namely pitching, rolling and yawing, of the scaling sample machine;

transmitting control data in the motion process of the model unmanned aerial vehicle A to a single chip microcomputer of a three-axis turntable through a serial port communication module, outputting a control signal by the single chip microcomputer to control the deflection of a control surface of a scaling model machine, and displaying the rudder amount of the model unmanned aerial vehicle A and the sizes of the four rotor motors and the accelerator of the fixed wing motor by the rotation of the four rotor motors and the fixed wing motor;

the control data comprises rudder amount, four-rotor motor accelerator, fixed wing motor accelerator and the like;

and fifthly, monitoring the state quantities of the model unmanned aerial vehicle A in the flying process, such as the position, the attitude, the speed, the deflection angle of a control plane, the accelerator of a fixed wing motor, the rotating speed of a four-rotor motor and the like, by a flight data monitoring module in real time, drawing curve changes and displaying real-time state quantity data.

And step six, transmitting information such as control surface action, longitude and latitude, height, speed, pitch angle and the like of the model unmanned aerial vehicle A to the three-dimensional view module through UDP communication, thereby realizing the full-flow view display of the taking-off and landing of the model unmanned aerial vehicle A.

The invention has the advantages that:

(1) according to the semi-physical simulation system of the composite unmanned aerial vehicle, by designing the scaling prototype of the composite unmanned aerial vehicle, the actions and the variation trends of a control surface, a four-rotor motor and a fixed wing motor of the composite unmanned aerial vehicle in the flight process can be observed more intuitively; by being fixed on the three-axis turntable, the three-axis turntable drives the scaling model machine to move when moving, and the attitude change of the airplane during flying can be simulated

(2) According to the semi-physical simulation system of the combined unmanned aerial vehicle, by designing the flight data monitoring module, data monitoring in the operation process of a mathematical model of the combined unmanned aerial vehicle is realized, the flight state of the combined unmanned aerial vehicle is rapidly known, the characteristics of the combined unmanned aerial vehicle during flight are analyzed, and data change in the flight process is analyzed;

(3) according to the semi-physical simulation system of the composite unmanned aerial vehicle, by designing the three-dimensional view module, the whole process from taking off to landing of the three-dimensional model of the composite unmanned aerial vehicle can be visually shown through three-dimensional view software;

(4) the combined type unmanned aerial vehicle semi-physical simulation system can effectively save the cost in the development process of the combined type unmanned aerial vehicle control system, improve the efficiency, and simultaneously realize human-computer interaction and carry out simulated flight training.

Drawings

Fig. 1 is a schematic structural view of a composite unmanned aerial vehicle according to the present invention;

FIG. 2 is a schematic view of a three-axis turret designed in the present invention;

FIG. 3 is a schematic diagram of a scale model of the hybrid unmanned aerial vehicle according to the present invention;

FIG. 4 is a schematic diagram of a semi-physical simulation method of the hybrid unmanned aerial vehicle according to the present invention;

fig. 5 is a flowchart of the semi-physical simulation method of the composite unmanned aerial vehicle of the invention.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings.

The invention provides a combined type unmanned aerial vehicle semi-physical simulation system. As shown in fig. 1, the simulation system of the composite unmanned aerial vehicle comprises a composite unmanned aerial vehicle mathematical model, a three-dimensional view module, a three-axis turntable (including a turntable structure and a turntable control module), a composite unmanned aerial vehicle scale model machine, a flight data monitoring module, a flight control module, a ground station and communication modules among the parts.

The semi-physical simulation system is realized on the basis of realizing data communication between the flight control module and the composite unmanned aerial vehicle mathematical model, wherein the flight control module outputs control quantity to the mathematical model, and the mathematical model provides information such as the position, the attitude and the like of the unmanned aerial vehicle model and feeds the information back to the flight control module, so that the flight control module realizes flight track planning and flight attitude control on the mathematical model;

the ground station is used for transmitting a control command; the three-axis turntable is used for visually displaying the posture movement of the unmanned aerial vehicle model; the compound unmanned aerial vehicle scaling model machine is used for displaying the actions of a control surface, a four-rotor motor and a fixed wing motor in the movement process of the unmanned aerial vehicle; the three-dimensional view module is used for displaying the whole flight process of the three-dimensional compound unmanned aerial vehicle model, including vertical take-off, landing, mode switching and the like; the flight data monitoring module is used for monitoring data (attitude angle, attitude angular velocity, airspeed, height and the like) in the combined type unmanned aerial vehicle model in real time and drawing a curve so as to better analyze the change of the model in the operation process.

The composite unmanned aerial vehicle mathematical model, the three-dimensional view module, the flight data monitoring module and the ground station run in a PC; the three-axis rotary table, the combined type unmanned aerial vehicle scaling model machine and the flight control module are physical objects. Data transmission between the composite unmanned aerial vehicle mathematical model and the flight control module is realized through one path of serial port communication; the data communication between the mathematical model of the combined unmanned aerial vehicle and the three-axis rotary table is realized through the serial port communication of the other path; the compound unmanned aerial vehicle scaling model machine is placed on the three-axis rotary table, and the three-axis rotary table outputs signals to control the movement of the motor and the control surface in the compound unmanned aerial vehicle scaling model machine.

The composite unmanned aerial vehicle mathematical model is a simulated mathematical model obtained by performing simulation modeling on a real unmanned aerial vehicle A in a PC. The simulation mathematical model comprises a motor module, an aerodynamic force and moment resolving module and a six-degree-of-freedom motion equation module and is mainly used for completing the resolving of the attitude and the position of the model unmanned aerial vehicle A.

The information such as the position, the attitude, the speed and the like of the model unmanned aerial vehicle A is input into a flight control module, and the control quantities such as the rudder quantity, the fixed wing motor throttle, the four-rotor motor throttle and the like of the current state of the model unmanned aerial vehicle A are obtained through the calculation of a control law in the flight control module;

the flight control module feeds back and inputs the control quantities to a motor module and a pneumatic power and moment calculation module in the simulation mathematical model again to calculate force and moment, and inputs the force and moment to a six-degree-of-freedom motion equation module to calculate to obtain information such as the attitude, the position, the speed and the acceleration of the model unmanned aerial vehicle A, so that closed-loop communication is formed;

the simulation mathematical model and the flight control module are communicated according to a specified data communication protocol, so that data interaction between the unmanned aerial vehicle mathematical model and the flight control module is realized, and flight path planning and flight attitude control of the model unmanned aerial vehicle A are completed.

As shown in fig. 2, the three-axis turntable comprises a turntable structure and a turntable control module, and is used for physically displaying the attitude motion of the model unmanned aerial vehicle a, the three-axis turntable is structurally designed by means of a soilworks tool, and then is processed and assembled to obtain an actual three-axis turntable, the three-axis turntable is mainly divided into three structural designs of a pitching motion frame, a rolling motion frame and a yawing motion frame, wherein the yawing motion frame and the rolling motion frame are in a half-i-shaped structure, one end of the yawing motion frame is used for mounting a steering engine, the other end of the yawing motion frame is used for mounting an angle sensor, all parts of the pitching motion frame are fastened through studs and screws to form a half-i-shaped frame,

as shown in fig. 3, the compound unmanned aerial vehicle scaling model machine is fixed above the three-axis turntable, and the scaling model machine is driven by the movement of the three-axis turntable, so that the change of the attitude angle of the scaling model machine, such as the actions of a control plane, a four-rotor motor and a fixed-wing motor, is realized; the driver adopts a steering engine, and the three-axis turntable is used for displaying the three-axis attitude angle, so that the requirement on the angle control of the three-axis turntable is high, and the steering engine is adopted as the driver; the sensor adopts an angle sensor based on a Hall principle, the turntable control module adopts a single chip microcomputer as a controller, and digital quantity acquired by the sensor is converted into analog quantity through digital-to-analog conversion in the single chip microcomputer, so that the current attitude angle is measured; the three-axis turntable is provided with three steering engines and three sensors in total, and is meshed through gear transmission with the transmission ratio of 1, so that the current angle of a yaw angle is measured; the rotary table has three degrees of freedom, so that the control steering engine and the wiring of the acquisition sensor need to be connected through a slip ring, the slip ring adopts an annular structure, a rotating shaft penetrates through the inside of the slip ring, and the slip ring is fixedly connected with the base through a screw; and the steering engine and the sensor are fixedly connected by screws. The three-axis rotary table can move with three degrees of freedom by means of three serially connected moving frames, namely pitching motion, rolling motion and yawing motion.

Meanwhile, the single chip microcomputer receives control signals of the rudder quantity, the four-rotor motor accelerator, the fixed-wing motor accelerator and the like sent by the mathematical model, and controls deflection of a control surface in the scaling model machine and rotation of the four-rotor motor and the fixed-wing motor to show the size change of the rudder quantity, the four-rotor motor accelerator and the fixed-wing oil engine accelerator in the simulation operation process of the model unmanned aerial vehicle A in the PC.

The flight data monitoring module collects and displays information such as attitude angle, attitude angular velocity, longitude and latitude, height and the like of the model unmanned aerial vehicle A in the operation process in a curve mode, quickly judges the current operation state of the model unmanned aerial vehicle A, marks abnormal flight data and corresponding time in the flight process, and can also play back the previous flight data.

The three-dimensional view module is used for displaying the full-flow flight of the model unmanned aerial vehicle A, a three-dimensional model of the composite unmanned aerial vehicle A is built in the PC through 3D modeling, the composite unmanned aerial vehicle A is led into the three-dimensional view module, corresponding structures in the three-dimensional model are driven to move through the actions of three control surfaces of an aileron, a rudder and an elevator of the model unmanned aerial vehicle A, a fixed wing oil engine and a four-rotor motor, and the position and the posture of the three-dimensional model in the three-dimensional view module are changed through inputting longitude and latitude, height and posture, so that the three-dimensional simulated flight of the model unmanned aerial vehicle A is realized.

The semi-physical simulation system runs in the following process, firstly, a composite unmanned aerial vehicle mathematical model is run in MATLAB/Simulink, when the mathematical model runs, data of the model can be transmitted to a flight control module and a three-axis turntable through a serial port and also can be stored in a Workspace of the MATLAB, and meanwhile, the data is transmitted to a three-dimensional view module through UDP communication. At this moment, flight data monitoring module, triaxial revolving stage, combined type unmanned aerial vehicle scaling model machine and three-dimensional view module are in order simultaneously, when carrying out flight instruction through the ground station, flight data monitoring module can draw the curve according to the state change of model, and triaxial revolving stage and scaling model machine can carry out the action of unmanned aerial vehicle attitude angle, control surface and motor, and three-dimensional view module can show three-dimensional combined type unmanned aerial vehicle's flight to realize semi-physical simulation system's normal operating.

As shown in fig. 4, firstly, a mathematical model of the composite unmanned aerial vehicle is constructed (constructed in MATLAB/Simulink and operated in the Simulink environment), and then the mathematical model is communicated with a flight control module, a three-axis turntable, a flight data monitoring module and a three-dimensional sight glass module respectively; the flight control module receives and feeds back the instruction of the opposite station; the three-axis turntable drives a scaling model machine of the composite unmanned aerial vehicle to make the same posture as that of the model unmanned aerial vehicle; the flight data monitoring module monitors all data of the mathematical model unmanned aerial vehicle in real time; and the three-dimensional view module is used for displaying the modeled composite unmanned aerial vehicle three-dimensional model. The combined type unmanned aerial vehicle mathematical model is built through MATLAB/Simulink, arrow "1" represents the data communication between mathematical model and the flight control module, and serial communication is adopted in this communication, and the accessible adds serial module in Simulink, sets up serial number, baud rate, and the data bit, stop bit check-up mode etc. realize unmanned aerial vehicle mathematical model and flight control module's communication, and serial standard interface adopts the RS-232 standard. The data transmitted by the mathematical model to the flight control module includes: the attitude angle, the attitude angular velocity, the longitude and latitude, the height and other GPS information, and the data output frequency can be set in Simulink; the flight control module transmits the control quantity of the mathematical model, including the fixed wing motor, the four-rotor motor, the aileron rudder quantity, the elevator rudder quantity and the like, and the data output frequency can be set in the flight control system. Arrow "6" indicates that the data interaction of ground station and flight control module, thereby this communication accessible radio station carries out the data transmission of accomplishing flight instruction and unmanned aerial vehicle state quantity.

An arrow 3 represents data transmission of state quantity (such as attitude angle, attitude angular velocity and the like) of an unmanned aerial vehicle model in Simulink, the state quantity is transmitted to Workspace in MATLAB, a flight data monitoring module is compiled through the MATLAB to realize monitoring of the state quantity of the composite unmanned aerial vehicle model in the operation process, and graphical output of the state quantity is realized; arrow '4' represents the data interaction between the mathematical model and the three-dimensional view module, the current longitude and latitude, attitude angle, speed, rudder amount and other information of the unmanned aerial vehicle can be transmitted to the three-dimensional view software flight through UDP communication, the three-dimensional display of the mathematical model is completed, in the UDP communication process, the communication between the unmanned aerial vehicle and the three-dimensional view software flight is adopted, and the IP address is set to be 127.0.0.1. Arrow "5" indicates that the built three-dimensional unmanned aerial vehicle model is imported into the Flightgear, the model can be drawn by using AC3D software, and finally, the AC-format file is imported.

Arrow '2' represents the transmission of control quantities such as the attitude angle, the rudder quantity, the fixed wing motor, the four-rotor motor and the like of the unmanned aerial vehicle, the communication mode also adopts serial port communication, serial port numbers different from those in '1' are adopted, the control panel adopts an STM32 single chip microcomputer, the serial port of the single chip microcomputer receives data, the steering engine, the motor are driven and the sensor signals are acquired by programming a program, the data of a composite unmanned aerial vehicle mathematical model in MATLAB/Simulink is received by configuring the serial port, the movement of the three-axis turntable and the scaling model machine is realized by driving the steering engine and the motor, and the current angle of the three-axis turntable is acquired by the sensor; arrow 7 indicates the action of fixing the scaling sample on the rotary table and displaying the attitude angle of the scaling sample through the movement of the rotary table.

As shown in fig. 5, the specific steps are as follows:

step one, establishing a simulation mathematical model aiming at the composite unmanned aerial vehicle A in MATLAB/Simulink software;

the simulation mathematical model comprises a motor module, a pneumatic force and moment resolving module and a six-degree-of-freedom motion equation module;

the mathematical modeling equation of the motor module in the frequency domain is as follows:

ω represents the motor speed, C_RThe curve coefficient of the motor is represented, the throttle of the motor is represented, and the value is between 0 and 1, omega_bRepresenting the motor curve constant, T_mDenotes the motor response time constant and s denotes the differential term in the frequency domain.

F＝C_t*ω*ω

F denotes the force generated by a single motor, C_tRepresenting the single-paddle coefficient of tension.

The inputs of the aerodynamic force and moment calculation module are an attack angle α, a sideslip angle β and an elevator deflection angle of the aircraft_eAileron declination angle_aRudder deflection angle_rThe output is aerodynamic force and aerodynamic moment.

The aerodynamic and moment equations are as follows:

the aerodynamic forces acting on the aircraft are split into a drag D, a lift L and lateral forces C, C_DIs the coefficient of resistance, C_CIs the coefficient of lateral force, C_LIs the lift coefficient, ρ is the air density, V is the flight velocity, S is the reference area of the aircraft;

the aerodynamic moment is decomposed into a roll moment L_rollA pitching moment M and a yawing moment N. C_lIs the roll moment coefficient, C_mIs the coefficient of pitching moment, C_nIs the yaw moment coefficient, b is the wing span length, C_AIs the average aerodynamic chord length of the wing.

The six-degree-of-freedom motion equation is as follows:

centroid kinetic equation:

(u, v, w) represents the x, y, z axis velocity components in the body coordinate system,the variable rate of the speed of the x, y and z axes in the body coordinate system is shown, and (p, q and r) are the angular speed components of the x, y and z axes in the body coordinate system. And (phi, theta, psi) are rolling angles, pitching angles and yaw angles of x, y and z axes in a body coordinate system. g represents the acceleration of gravity, m represents the mass of the drone, F_x,F_y,F_zRepresenting the components of the combined external force received by the unmanned aerial vehicle in a body coordinate system x, y and z;

equation of rotational dynamics:

(I_x,I_y,I_z) Is the moment of inertia of the aircraft about the x, y, z axes, I_zxIs the product of inertia of the aircraft about the zx axis;

centroid kinematics equation:

representing the rate of change of the three-axis position of the aircraft in a terrestrial coordinate system,

rotational kinematic equation:

wherein the content of the first and second substances,the roll angle change rate, the pitch angle change rate and the yaw angle change rate;

inputting the state quantity of the model unmanned aerial vehicle A into a flight control module through a serial port communication module, resolving out a control quantity through a control law, and driving a control plane and a motor throttle of the model unmanned aerial vehicle A to act;

the state quantity comprises the position, the posture, the speed, the acceleration and the like of the model unmanned aerial vehicle A;

for the composite unmanned aerial vehicle, the control law design comprises control law design in a four-rotor mode, control law design in a fixed wing mode and control law design in a transition mode; and PID controllers are adopted by control laws in the three modes.

For a four-rotor mode, the control law design comprises longitudinal outer ring height control-inner ring pitch angle control; course outer ring course distance/speed control-inner ring course angle control; lateral outer ring lateral distance/velocity control-inner ring roll angle control.

For the fixed wing mode, the control law design comprises longitudinal outer ring height-inner ring pitch angle control; course horizontal position/course control; controlling lateral deviation distance of the transverse outer ring and roll angle of the inner ring; and airspeed control.

And for the control of the transition mode, carrying out certain combination on the control law of the four-rotor mode and the control law of the fixed wing mode according to the control requirement to obtain the control of the transition mode.

Taking altitude control as an example, the process of driving model unmanned aerial vehicle a to move is as follows:

for fixed wing modes. Firstly, setting an expected height, and comparing the expected height with the current height of the model unmanned aerial vehicle A to obtain a height error; then, resolving by an outer ring height controller (PID controller) to obtain an expected pitch angle required by the unmanned aerial vehicle to reach the expected height under the fixed wing mode; comparing the expected pitch angle with the current pitch angle to obtain a pitch angle error, resolving the pitch angle error through an inner ring attitude controller (PID controller) to obtain the elevator rudder amount required by reaching the expected pitch angle, inputting the elevator rudder amount obtained through calculation into an aerodynamic force calculation module of a simulation mathematical model, and generating aerodynamic force and moment so as to drive the model unmanned aerial vehicle A to move.

For a four-rotor mode. Firstly, setting an expected height, and comparing the expected height with the current height of the model unmanned aerial vehicle A to obtain a height error; the expected lifting speed required by the unmanned aerial vehicle to reach the expected height in the four-rotor mode is obtained through calculation by a height controller (PID controller); the expected lifting speed is compared with the current lifting speed to obtain a lifting speed error, the lifting speed error is resolved by a lifting speed controller (PID controller), a four-rotor motor throttle required for reaching the expected lifting speed is obtained, the calculated four-rotor motor throttle is input into a motor module of a simulation mathematical model to generate lift force and torque, and therefore the model unmanned aerial vehicle A under the four-rotor mode is driven to move.

For transition modes. Firstly, the four-rotor wing mode rises to a certain height, and then the accelerator of the fixed wing motor starts accelerating. After the airspeed of the unmanned aerial vehicle reaches the switching speed, the throttle of the four-rotor motor is reduced to zero all the time; and meanwhile, the accelerator of the fixed wing motor continues accelerating to reach the airspeed required by normal flight, and the fixed wing motor is lifted by height control under the mode of the fixed wing.

Thirdly, transmitting attitude angle data in the movement process of the model unmanned aerial vehicle A to a rotary table control module of a three-axis rotary table through a serial port communication module, controlling a steering engine to drive a pitching movement frame, a rolling movement frame and a yawing movement frame which are connected in series to move by the rotary table control module, further driving a scaling prototype, and realizing attitude movement display of three degrees of freedom, namely pitching, rolling and yawing, of the scaling prototype;

transmitting control data in the motion process of the model unmanned aerial vehicle A to a single chip microcomputer of a three-axis turntable through a serial port communication module, outputting a control signal by the single chip microcomputer to control the deflection of a control surface of a scaling model machine, and displaying the rudder amount of the model unmanned aerial vehicle A and the sizes of the four rotor motors and the accelerator of the fixed wing motor by the rotation of the four rotor motors and the fixed wing motor;

the control data comprises rudder amount, four-rotor motor accelerator, fixed wing motor accelerator and the like;

and fifthly, monitoring the state quantities of the model unmanned aerial vehicle A in the flying process, such as the position, the attitude, the speed, the deflection angle of a control plane, the accelerator of a fixed wing motor, the rotating speed of a four-rotor motor and the like, by a flight data monitoring module in real time, drawing curve changes and displaying real-time state quantity data.

For the combined type unmanned aerial vehicle, when transiting to the fixed wing mode by the rotor mode, transition mode's control is very crucial, and flight data monitoring module can more audio-visual demonstration model unmanned aerial vehicle A's the quantity of state change when transition mode. And the attitude angle, the deflection angle of the control plane and the rotating speed and the variation trend of the fixed-wing oil engine accelerator and the motor displayed in the flight data monitoring module are compared and verified to be consistent with the actual moving attitude of the three-axis turntable, the deflection angle of the control plane in the scaling model machine and the rotating speed and the variation trend of the fixed-wing oil engine accelerator and the motor.

And step six, transmitting information such as control surface action, longitude and latitude, height, speed, pitch angle and the like of the model unmanned aerial vehicle A to the three-dimensional view module through UDP communication, thereby realizing the full-flow view display of the taking-off and landing of the model unmanned aerial vehicle A.