CN112364432B - Control method for carrier hanging and throwing separation process - Google Patents

Abstract

The invention proposes a control method for the launch and separation process of a carrier aircraft. First, the overall parameters of the aircraft and the launch and separation parameters are obtained as design data, and the control rudder deflection angle and initial value of the start-up control time required to maintain a stable separation attitude are calculated, and the calculation is determined. The attitude angle command value of the separation process is calculated, and then the control rudder deflection angle and the initial value of the control start time are verified through separation dynamic trajectory simulation calculations. The attitude angle control law can be designed according to the classic control method to form a release separation control plan. Finally, through Monte Carlo simulation tests the effectiveness of the scheme. The advantage of the present invention compared with the prior art is that in the separation control design, the initial rudder surface deflection angle is increased in response to the aerodynamic interference of the carrier aircraft during the separation process of the existing plane-symmetrical aircraft, which effectively solves the problem of launching aircraft with wing surfaces. Separation safety issues, and the fastest separation attitude angle command is added during the separation process, which greatly reduces the risk of collision with the carrier aircraft and improves the safety of release and separation.

Description

A control method for the separation process of carrier aircraft hanging and flying

Technical field

The invention relates to a method for controlling the separation process of carrier aircraft in flight and is suitable for the field of external plug-in delivery control.

Background technique

The unpowered space-to-ground symmetrical aircraft is a key area of high-tech development in the aerospace industry in major countries in the world at this stage. Through the unremitting efforts of all major aerospace countries, the symmetrical space-to-ground aircraft has made great progress in the verification of key technologies. However, the process of putting any technology into product into use is a tortuous process of scientific and technological exploration. Before the United States launched the development of aerospace vehicles, it used carrier aircraft such as White Knight to conduct flight and launch demonstration verification tests to fully verify key technologies. For unpowered space-to-ground symmetrical aircraft, flying and launching is a commonly used key technology flight verification test method.

Just like the release of external missiles, the safety issue of the separation of the face-to-face aircraft and the carrier aircraft is also a key issue and difficulty in the separation of the missile. The so-called bomb separation means that the separation of the missile and the carrier aircraft does not exceed the missile or the carrier aircraft or other airborne objects. design limits, and will not cause damage to or collide with the carrier aircraft, suspension devices or other suspended objects, or have adverse side effects on them. However, unlike axisymmetric missiles, plane-symmetric aircraft have more severe aerodynamic interference problems with the carrier aircraft. For plane-symmetric aircraft that rely on aerodynamic effects for flight and control, separation safety issues are more prominent. Therefore, during separation Effective flight control methods in the zone are particularly important.

Contents of the invention

The technical problem solved by the present invention is to overcome the shortcomings of the existing technology, provide a method for controlling the separation process of carrier aircraft in flight, solve the problem of safe control of external separation of symmetrical aircraft, and provide a suitable separation method for this type of aircraft. Control plan.

The technical solution of the present invention is: a method for controlling the separation process of carrier aircraft in flight, the steps are as follows:

1) Obtain the overall parameters of the aircraft and the release separation parameters as design data;

2) According to the aerodynamic interference characteristics of the symmetrical aircraft opposite the separation zone, calculate the control rudder deflection angle required to maintain attitude stability, determine the initial separation rudder deflection angle, and provide an initial value of the control start time based on experience;

3) Calculate the relationship between the separation trajectory inclination angle and the angle of attack, and determine the attitude angle command value during the separation process;

4) Carry out separation dynamic trajectory simulation calculations to obtain the relationship between the attitude and trajectory parameters over time before taking control under the initial rudder angle and start-up time determined in step 2), and confirm that the attitude and attitude before take-off are stable and consistent with the carrier aircraft. No collision occurs;

5) Design the attitude angle control law according to the classic control method;

6) Carry out Monte Carlo simulation analysis based on the initial rudder deflection angle and control start time determined in step 2) and the control law designed in step 5) to control the attitude of the separation process to be stable and not to collide with the carrier aircraft.

The specific process of step 1) is: obtain the overall parameters of the aircraft and the release and separation parameters as design data. The overall parameters of the aircraft include the aircraft shape parameters, mass and inertia characteristic parameters, including aerodynamic data that interferes with the separation zone of the carrier aircraft; the release and separation parameters include the launch and separation parameters. Altitude, speed, Mach number, angle of attack/sideslip angle, attitude angle, attitude angular velocity, and also includes parameter deviations.

The initial value of the control time in step 2) is 1s.

The calculation formula for the separation initial rudder deflection angle in step 2) is as follows:

C _l (Ma ^* ,α ^* ,β ^* ,δ _a ^* ,δ _e ^* ,δ _r ^* )=0

C _m (Ma ^* , α ^* , β ^* , δ _a ^* , δ _e ^* , δ _r ^* )=0

C _n (Ma ^* , α ^* , β ^* , δ _a ^* , δ _e ^* , δ _r ^* )=0

Among them: C _l (.), C _m (.), C _n (.) are the roll, pitch, and yaw moments respectively with respect to Mach number Ma, angle of attack α, sideslip angle β, aileron δ _a , and elevator δ The functional expression of _e and rudder δ _r ; “*” represents the values of Mach number, angle of attack, sideslip angle, elevator, aileron, and rudder when the roll, pitch, and yaw moments are zero, where Mach number, angle of attack, and rudder are The angle and sideslip angle are given by step 1);

The values of aileron, elevator and rudder are obtained by solving the above three equations.

The specific calculation method of step 3) is: the particle dynamics equation of the unpowered aircraft in the wind axis system is described as:

The particle dynamics equation of the aircraft in the wind axis system is described as:

In the formula, V is the velocity, m is the mass, g is the gravity acceleration, γ is the trajectory inclination angle, D and L respectively represent the aerodynamic drag and lift acting on the unpowered aircraft, and are further rewritten as:

represent the aerodynamic drag and lift acting on the unpowered aircraft respectively, S is the reference area, C _L is the lift coefficient, C _D is the drag coefficient, Ma is the Mach number, α is the angle of attack, and dynamic pressure/> ρ is the density of the atmosphere, V is the airspeed of the aircraft; according to the separation parameters and overall parameters of the aircraft in step 1) and the above equation, determine the relationship between the trajectory inclination angle and the angle of attack based on the release separation parameters altitude, speed, Mach number and the overall parameters of the aircraft. , take the angle of attack corresponding to the maximum separation trajectory inclination angle, and complete the attitude angle command design.

In the step 4), the separation dynamic trajectory simulation calculation is carried out. Specifically, the initial rudder deflection angle and start-up time determined in step 2) are transferred to the aerodynamics major, and the relationship between the attitude and trajectory parameters before the start-up is numerically calculated over time. If the calculation If the attitude diverges during the separation process or collides with the carrier aircraft, the calculation of the initial trim rudder deflection angle will be re-calculated, and the initial value of the start-up control time will be adjusted at the same time.

The specific calculation method of step 5) is: deviate the overall data of the aircraft and the initial separation parameters, and perform Monte Carlo simulation analysis. If the attitude can be guaranteed not to diverge under various deviation conditions and the separation process will not interfere with the carrier aircraft Then it is over, and the design is completed to obtain the separation start control time, separation initial rudder surface deflection angle and attitude control law, and form a separation control plan, otherwise return to step 2) and start again.

The advantage of this invention compared with the existing technology is that in the separation control design, the initial rudder surface deflection angle is increased to deal with the aerodynamic interference of the carrier aircraft during the separation process of the existing plane-symmetric aircraft, which effectively solves the problem of aircraft with airfoils. Drop separation security issues. At the same time, the fastest separation attitude angle command is added during the separation process, which greatly reduces the risk of collision with the carrier aircraft and improves the safety of release and separation.

Description of drawings

Figure 1 is a flow chart of the method of the present invention.

Detailed ways

As shown in Figure 1, a method for controlling the separation process of carrier aircraft during flight and release, the steps are as follows:

1. Obtain the overall parameters of the aircraft and the release and separation parameters as design data. The overall parameters of the aircraft include the aircraft shape parameters, mass and inertia characteristic parameters, including aerodynamic data that interferes with the separation zone of the carrier aircraft; the release and separation parameters include the release height, speed, and Mach number. , angle of attack/sideslip angle, attitude angle, attitude angular velocity, and also includes parameter deviations.

2. This step mainly considers the strong aerodynamic interference of the aircraft in the separation zone due to the symmetry of the opposite side of the carrier aircraft. This article calculates the initial separation rudder deflection angle required to maintain a stable attitude based on the aerodynamic interference characteristics of the symmetrical aircraft opposite the separation zone. At the same time, the initial control time is given based on experience, which is generally 1 second. The calculation formula for the initial rudder surface deflection angle is as follows:

C _l (Ma ^* ,α ^* ,β ^* ,δ _a ^* ,δ _e ^* ,δ _r ^* )=0

C _m (Ma ^* , α ^* , β ^* , δ _a ^* , δ _e ^* , δ _r ^* )=0

C _n (Ma ^* , α ^* , β ^* , δ _a ^* , δ _e ^* , δ _r ^* )=0

Among them: C _l (.), C _m (.), C _n (.) are the roll, pitch, and yaw moments respectively with respect to Mach number Ma, angle of attack α, sideslip angle β, aileron δ _a , and elevator δ The functional expression of _e and rudder δ _r ; “*” represents the values of Mach number, angle of attack, sideslip angle, elevator, aileron, and rudder when the roll, pitch, and yaw moments are zero, where Mach number, angle of attack, and rudder are The angle and sideslip angle are given by step 1), then three equations can be solved, the values of aileron, elevator and rudder.

3. Calculate the relationship between the separation trajectory inclination angle and the separation attitude angle command, and determine the attitude angle command. The specific calculation method is: the particle dynamics equation of an unpowered aircraft in the wind axis system is described as:

The particle dynamics equation of the aircraft in the wind axis system can be described as:

In the above formula, V is the velocity, m is the mass, g is the gravity acceleration, γ is the trajectory inclination angle, D and L respectively represent the aerodynamic drag and lift acting on the unpowered aircraft. They can be further rewritten as:

represent the aerodynamic drag and lift acting on the unpowered aircraft respectively, S is the reference area, C _L is the lift coefficient, C _D is the drag coefficient, Ma is the Mach number, α is the angle of attack, and dynamic pressure/> ρ is the density of the atmosphere, and V is the airspeed of the aircraft. According to the separation parameters and the overall parameters of the aircraft in step 1), and the above four equations, the relationship between the trajectory inclination angle and the angle of attack can be determined based on the release separation parameters height, speed, Mach number and the overall parameters of the aircraft, and the maximum separation trajectory inclination angle can be determined Corresponding angle of attack, complete the attitude angle command design.

4. Carry out separation dynamic trajectory simulation calculation, specifically transfer the initial rudder deflection angle and start-up time determined in step 2) to the aerodynamics major, and numerically calculate the relationship between the attitude and trajectory parameters before the start-up over time. If the calculation shows that the separation process is If the attitude diverges or collides with the carrier aircraft, the calculation of the initial trim rudder deflection angle will be recalculated, and the initial value of the control start time will be adjusted at the same time.

5. Complete the attitude control law design according to the classic engineering control method. The specific design method is a general method in this field.

6. Deflect the overall data of the aircraft and the initial separation parameters, and perform Monte Carlo simulation analysis. If the attitude can be guaranteed not to diverge under various deviation conditions and the separation process will not interfere with the carrier aircraft, the design is completed. Separate the control start time, separate the initial rudder deflection angle and the attitude control law to form a separate control plan, otherwise return to step 2) and start again.

The parts of the present invention that are not described in detail are common knowledge to those skilled in the art.

Claims (7)

1. A method for controlling the flight separation process of a carrier aircraft, which is characterized by the following steps: 1) Obtain the overall parameters of the aircraft and the release separation parameters as design data; 2) According to the aerodynamic interference characteristics of the symmetrical aircraft opposite the separation zone, calculate the control rudder deflection angle required to maintain attitude stability, determine the initial separation rudder deflection angle, and provide an initial value of the control start time based on experience; 3) Calculate the relationship between the separation trajectory inclination angle and the angle of attack, and determine the attitude angle command value during the separation process; 4) Carry out separation dynamic trajectory simulation calculations to obtain the relationship between the attitude and trajectory parameters over time before taking control under the initial rudder angle and start-up time determined in step 2), and confirm that the attitude and attitude before take-off are stable and consistent with the carrier aircraft. No collision occurs; 5) Design the attitude angle control law according to the classic control method; 6) Carry out Monte Carlo simulation analysis based on the initial rudder deflection angle and control start time determined in step 2) and the control law designed in step 5) to control the attitude of the separation process to be stable and not to collide with the carrier aircraft. 2. A method for controlling the flight and release separation process of a carrier aircraft according to claim 1, characterized in that: the specific process of step 1) is: obtaining the overall parameters of the aircraft and the release and separation parameters as design data, wherein the overall parameters of the aircraft include The aircraft shape parameters, mass and inertia characteristic parameters, including aerodynamic data interfered with by the separation zone of the carrier aircraft; the launch and separation parameters include launch altitude, speed, Mach number, angle of attack/sideslip angle, attitude angle, attitude angular velocity, and also include parameter deviations . 3. A method for controlling the separation process of carrier aircraft in flight and release according to claim 1, characterized in that: the initial value of the control time in step 2) is 1s. 4. A method for controlling the separation process of carrier aircraft in flight and release according to claim 1, characterized in that: the calculation formula of the initial separation rudder deflection angle in step 2) is as follows: Among them: C _l (.), C _m (.), C _n (.) are the roll, pitch, and yaw moments respectively with respect to Mach number Ma, angle of attack α, sideslip angle β, aileron δ _a , and elevator δ The functional expression of _e and rudder δ _r ; “*” represents the values of Mach number, angle of attack, sideslip angle, elevator, aileron, and rudder when the roll, pitch, and yaw moments are zero, where Mach number, angle of attack, and rudder are The angle and sideslip angle are given by step 1); The values of aileron, elevator and rudder are obtained by solving the above three equations. 5. A method for controlling the separation process of a carrier aircraft in flight according to claim 1, characterized in that: the specific calculation method of step 3) is: the particle dynamics equation of the unpowered aircraft in the wind axis system is described as: The particle dynamics equation of the aircraft in the wind axis system is described as: In the formula, V is the velocity, m is the mass, g is the gravity acceleration, γ is the trajectory inclination angle, D and L respectively represent the aerodynamic drag and lift acting on the unpowered aircraft, and are further rewritten as: D and L respectively represent the aerodynamic drag and lift acting on the unpowered aircraft. S is the reference area, C _L is the lift coefficient, C _D is the drag coefficient, Ma is the Mach number, α is the angle of attack, and dynamic pressure/> ρ is the density of the atmosphere, V is the airspeed of the aircraft; according to the separation parameters and overall parameters of the aircraft in step 1) and the above equation, determine the relationship between the trajectory inclination angle and the angle of attack based on the release separation parameters altitude, speed, Mach number and the overall parameters of the aircraft. , take the angle of attack corresponding to the maximum separation trajectory inclination angle, and complete the attitude angle command design. 6. A method for controlling the separation process of a carrier aircraft in flight according to claim 1, characterized in that: in step 4), separation dynamic trajectory simulation calculation is carried out, specifically the initial rudder deflection angle determined in step 2) and start control time are passed to the aerodynamics major, and the relationship between attitude and trajectory parameters before start control is numerically calculated over time. If the calculation shows that the attitude during the separation process diverges or collides with the carrier aircraft, the calculation of the initial trim rudder deflection angle will be re-calculated, and at the same time Adjust the initial value of control start time. 7. A method for controlling the separation process of a carrier aircraft in flight according to claim 1, characterized in that: the specific calculation method of step 5) is: deviating the overall data of the aircraft and the initial separation parameters, and performing Monte Carlo Simulation analysis shows that if the attitude can be guaranteed not to diverge under various deviation conditions and the separation process will not interfere with the carrier aircraft, then the design is completed and the separation control time, separation initial rudder deflection angle and attitude control law are obtained to form separation. control plan, otherwise return to step 2) and start again.