KR20110092152A - Method for orbit transfer using flight path angle control, and aircraft using the same - Google Patents

Abstract

PURPOSE: An orbit transfer method using controls of a flight path angle and a flying object using the same are provided to estimate the converged required flight path angle base on the speed of vehicle through the limited repetitive calculation. CONSTITUTION: An orbit transfer method comprises the following steps. The minimum speed of arriving in to the range angle is estimated. If the input speed is not bigger than the value output by adding an estimated minimum speed and a predetermined critical speed, the added value is set up the input value. The demand flight path angle is estimated based on the input value(S110). The convergent demand flight path angle is estimated based on the input value and demand flight path angle.

Description

Orbital transition method by flight path angle control and a vehicle using the method {METHOD FOR ORBIT TRANSFER USING FLIGHT PATH ANGLE CONTROL, AND AIRCRAFT USING THE SAME}

The present invention relates to a method of performing a trajectory transition of the vehicle by controlling the flight path angle of the vehicle, and a vehicle using the method of controlling the flight path angle.

The flight trajectory and orbital transition of the vehicle will be described.

The orbital transition of the present invention is one of various orbital transition methods, and in particular, a two-point boundary problem, that is, a Lambert problem for sending an object from one point to another in the gravitational field. Is related to solving.

1 is a diagram illustrating an orbit into which a vehicle such as a satellite enters.

In order for the aircraft to enter a high altitude circular orbit, the vehicle first enters a low circular orbit. The low altitude circular track is also called a parking orbit. The vehicle checks each device during the parking trajectory.

The aircraft performs thrust after a suitable time passes to orbit toward the desired high altitude circular orbit. Thrust causing a speed change Δv ₁ enters the vehicle into an elliptical transition orbit at the low altitude circle altitude, and thrust causing a speed change Δv ₂ enters the vehicle into the high altitude circle orbit in the elliptic transition orbit.

When the vehicle performs the above-described orbital transition, the vehicle can be divided into being capable of controlling the magnitude of the velocity vector (hereinafter, abbreviating 'the magnitude of the velocity vector' as 'velocity'). In general, a vehicle using liquid fuel corresponds to a vehicle capable of controlling this speed, and a vehicle equipped with a kick motor using solid fuel corresponds to a vehicle that cannot control the speed.

The vehicle capable of controlling the speed may adjust the speed during the process of the orbital transition when performing the orbital transition. That is, the vehicle capable of controlling the speed may stop the thrust by closing the fuel valve when the vehicle achieves the desired speed at the desired position. Therefore, only a small error occurs in the performance. On the other hand, the speed control device for speed control may increase the weight of the vehicle or complicate the system of the vehicle. Liquid fuels commonly used in such vehicles also make fuel storage and fuel related maintenance difficult.

On the other hand, a vehicle whose speed cannot be controlled cannot control the magnitude and combustion time of the thrust once the engine is ignited once. In other words, a vehicle whose speed cannot be controlled uses a solid propellant, and therefore must exhaust all fuel after the ignition. The vehicle has a relatively large entry error because it cannot control the speed, but has the advantages of a simple system and easy maintenance.

Therefore, there is a need to provide an orbital transition method for a vehicle that cannot control the speed with the above advantages, and a separate guidance algorithm for the method must be designed.

Accordingly, an object of the present invention is to solve the above problems.

It is an object of the present invention to provide an orbital transition method for a vehicle having no speed control capability and a vehicle using the method. The orbital transition method can be used for orbital transitions when entering a low-altitude circular track from the earth and when entering a high-altitude circular track in a parking track.

Another object of the present invention is to provide a method for estimating the required flight path angle based on the speed of the aircraft and a method for estimating the required flight path angle converged by a limited iterative calculation, and an aircraft using the method. To provide.

Still another object of the present invention is to provide a flight path angle control method in consideration of a lead angle and a vehicle using the method.

It is still another object of the present invention to provide a method for estimating the converged required flight path angle by limiting the minimum value of the range angle and a vehicle using the method.

According to the present invention, there is provided a method for performing an orbital transition of a vehicle whose speed cannot be controlled. If not greater than the sum of the value as the value of the input speed, estimating the required flight path angle based on the input speed and based on the input speed and the calculated flight path angle flight path angle Controlling.

Advantageously, the method further comprises estimating a velocity-to-go difference between a demand velocity vector and a current velocity vector based on the input speed and the converged demand flight path angle and the increase demand velocity vector direction. It may further comprise the step of directing the thrust.

Preferably, the input speed may be the current speed of the vehicle, and when the range angle is less than a predefined range threshold, the range threshold may be used as the range angle, and the trajectory transition is one of the elliptical orbits. It may be an orbital transition from point to point on a circular orbit.

Preferably, the speed that is the basis of the input speed may be different according to the current trajectory of the vehicle.

Preferably, when the vehicle is in transition from one point of the parking track to one point of the elliptic orbit, a pseudo speed sum of the current speed of the vehicle and a speed parameter based on the simulation may be used as the input speed, and the aircraft is an ellipse. When the trajectory transition from one point of the track to one point of the circular track is in progress, the pseudo speed of the vehicle may be used as the input speed.

Preferably, when the vehicle is in a trajectory transition from one point of an elliptic orbit to a point of a circular orbit, if the range angle is smaller than a predefined range threshold, the range threshold may be used as the range angle. .

The vehicle according to the present invention includes a control unit for generating and transmitting a command for performing the orbital transition, and a thrust unit for generating a thrust by receiving the guide command of the control unit, the aircraft can not control the speed, the control unit Estimates the required flight path angle based on the speed of the vehicle, calculates an increase request speed vector based on the estimated required flight path angle, and generates an instruction to move the vehicle according to the increase request speed vector. Characterized in that.

Preferably, the control unit estimates the minimum speed for reaching the range angle, and if the input speed is not greater than the sum of the estimated minimum speed and the predefined speed threshold, the summed value as the value of the input speed. The estimated flight path angle is estimated based on the input speed, and the estimated flight path angle is determined by converging the estimated flight path angle. Can be used as flight path angle.

Preferably, the input speed may be a pseudo speed obtained by adding the current speed of the vehicle and the speed parameter based on the simulation, and the track transition may be a track transition from one point of the parking track to one point of the elliptic track.

Preferably, the input speed may be a current speed of a vehicle, and the controller may use the range threshold as the range angle when the range angle is smaller than a predefined range threshold, and the track transition is an ellipse. It may be an orbital transition from one point of the orbit to one point of the circular orbit.

Preferably, different speed references may be used as the basis of the input speed depending on the position of the vehicle.

Preferably, when the vehicle is in transition from one point of the parking track to one point of the elliptic orbit, a pseudo speed sum of the current speed of the vehicle and a speed parameter based on the simulation may be used as the input speed, and the aircraft is an ellipse. When the trajectory transition from one point of the track to one point of the circular track is in progress, the pseudo speed of the vehicle may be used as the input speed.

Preferably, when the vehicle is in the transition of the track from one point of the elliptical orbit to the point of the circular orbit, the aircraft may use the smaller of the range angle and the predefined range threshold as the range angle.

The present invention has the effect of providing an orbital transition method for a vehicle having no speed control capability and a vehicle using the method.

In addition, the present invention has the effect of providing a method capable of estimating the required flight path angle converged to a limited iteration based on the speed of the aircraft and a vehicle using the method.

In addition, the present invention has the effect of providing a flight path angle control method in consideration of the lead angle (lead angle) and the aircraft using the method.

In addition, the present invention has the effect of providing a method for estimating the converged flight path angle by limiting the minimum value of the range angle and the vehicle using the method.

1 is a diagram illustrating an orbit into which a vehicle such as a satellite enters.
2 is a flow chart illustrating a required flight path angle calculation and flight path angle control procedure according to an embodiment of the present invention.
3 is a diagram illustrating the transition of an orbit from an orbit to an elliptical orbit.
4 is a diagram showing the orbital transition from an elliptical orbit to a circular orbit.
5 is a flow chart illustrating a procedure for estimating the required flight path angle for velocity V. FIG.
6 is a diagram showing the relationship between the velocity vector, the flight path angle and the increase demand velocity vector of the vehicle.
7 is a flow chart illustrating a flight path angle control procedure for orbital transition.
8 shows γ _rp and the direction V _gp in which thrust should be applied in a region of small φ.
FIG. 9 is a diagram of the induction command obtained by the vehicle to exert thrust in the direction of the vector Vgp over time. FIG.
FIG. 10 is a diagram showing flight path angle γ and required flight path angle γ _r of the vehicle according to time.
FIG. 11 shows altitude of the vehicle over time. FIG.

The present invention applies to the orbital transition method of a vehicle and a vehicle using the method. However, the present invention is not limited thereto, and may be applied to an apparatus to which the technical spirit of the present invention may be applied and a method related thereto.

In this specification, the magnitude of the velocity vector is simply referred to as velocity.

Air vehicle in the present specification refers to the object of the comprehensive meaning that can move the position in the space or space, such as airplanes, rockets, spacecrafts and satellites.

In the present specification, the term 'not able to control the speed' means that the aircraft cannot adjust the output of the engine to the specific speed desired by the aircraft. A vehicle that changes the speed of the vehicle by igniting a specific engine among a plurality of engines in flight, or the output of the engine is reduced or completed as the fuel of a specific engine is exhausted, or the aircraft changes its direction of travel. It is not included in the case of 'uncontrollable speed'.

It is to be noted that the technical terms used herein are merely used to describe particular embodiments, and are not intended to limit the present invention. It is also to be understood that the technical terms used herein are to be interpreted in a sense generally understood by a person skilled in the art to which the present invention belongs, Should not be construed to mean, or be interpreted in an excessively reduced sense. In addition, when the technical terms used herein are incorrect technical terms that do not accurately express the spirit of the present invention, they should be replaced with technical terms that can be understood correctly by those skilled in the art. In addition, the general terms used in the present invention should be interpreted as defined in the dictionary or according to the context before and after, and should not be interpreted in an excessively reduced sense.

Also, the singular forms "as used herein include plural referents unless the context clearly dictates otherwise. In the present application, terms such as “consisting of” or “comprising” should not be construed as necessarily including all of the various components, or various steps described in the specification, wherein some of the components or some of the steps It should be construed that it may not be included or may further include additional components or steps.

In addition, terms including ordinal numbers, such as first and second, as used herein may be used to describe various components, but the components should not be limited by the terms. The terms are used only for the purpose of distinguishing one component from another. For example, without departing from the scope of the present invention, the first component may be referred to as the second component, and similarly, the second component may also be referred to as the first component.

When an element is referred to as being "connected" or "connected" to another element, it may be directly connected or connected to the other element, but other elements may be present in between. On the other hand, when a component is said to be "directly connected" or "directly connected" to another component, it should be understood that there is no other component in between.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings, and the same or similar components will be given the same reference numerals regardless of the reference numerals, and redundant description thereof will be omitted. In addition, in describing the present invention, when it is determined that the detailed description of the related known technology may obscure the gist of the present invention, the detailed description thereof will be omitted. In addition, it is to be noted that the accompanying drawings are only for easily understanding the spirit of the present invention and are not to be construed as limiting the spirit of the present invention by the accompanying drawings. The spirit of the invention should be construed to extend to all changes, equivalents, and substitutes in addition to the accompanying drawings.

The present invention provides a method of controlling the flight path angle of the vehicle to perform the orbital transition without controlling the speed of the vehicle.

2 is a flowchart illustrating a required flight path angle calculation procedure and a flight path angle control procedure according to an embodiment of the present invention.

First, the vehicle calculates a route for required flight path angle (RRFPA) for orbital transition (S110). The estimation is based on the speed of the vehicle.

Next, the vehicle performs a flight path angle control (FPAC) operation of the vehicle to achieve the estimated required flight path angle (S120).

The vehicle transmits an induction command based on the operation so that the actual flight path angle of the vehicle is changed (S130).

Using the above-described flight path angle control method, let's look at how the aircraft performs orbital transition.

First, the vehicle performs an orbital transition from a circle path to an ellipse path.

3 is a diagram illustrating an orbital transition from an circular orbit to an elliptical orbit.

In FIG. 3, the section from r ₀ to r ₁ is a transition section. The transition from the circular orbit to the elliptical orbit is performed in the transition section. That is, the vehicle ignites the first kick motor at r ₀ to move away from the parking trajectory, which is the orbit, to reach r ₁ . Since the speed control of the first kick motor is impossible, the vehicle performs the induction up to r ₁ using the flight path angle control method of the present invention. When the vehicle reaches r ₁ , the fuel of the first kick motor is exhausted, and the vehicle performs free flight from r ₁ to r ₂ .

Next, the vehicle performs an orbital transition from the elliptical orbit to the circular orbit.

4 is a diagram illustrating an orbital transition from an elliptical orbit to a circular orbit.

The air vehicle is to ignite the second kick motor at r ₂ and r ₃ reaches, when the vehicle has reached the r _3, the vehicle will run out of fuel and the second kick motor. If r ₃ in that a speed V _c is required to be circular orbit is achieved, the speed V of the vehicle should be V _c, and flight path of the speed vector V of the air vehicle angle γ is to comply with the γ _c. Here, _c = 0. Therefore, it is assumed that the speed capability V _cap of the second motor satisfies Equation 1 below.

Next, referring to FIG. 3, a method for calculating a required flight path angle according to an embodiment of the present invention (hereinafter, abbreviated as RRFPA) will be described.

The calculation method is for calculating a required flight path angle for an arbitrary input speed, and is a modification of the method using a Lambert routine. To facilitate understanding of the present invention, the Lambert routine is briefly described first.

The Lambert routine refers to a routine for obtaining a solution of a Lambert problem, and the Lambert Problem refers to a problem of finding a solution for sending an object from one point to another in the Earth's gravitational field. That is, the Lambert routine calculates and outputs the required flight path angle and the required speed when the required time is first determined in order to send an object from one point to another point in the earth's gravity field. A required speed vector may be configured using the required flight path angle and the required speed output through the routine, and an increased required speed vector may be obtained using Equation 2 below using the required speed vector.

If the vehicle is guided using the increased demand velocity vector and the thrust is stopped at the moment when V _g = 0, the aircraft reaches a predetermined flight time at a desired point. V _g = 0 means that the value of the two vectors V _r and V is equal, which also means that V _r = V, yet the path angle and the flight path of each match of the current velocity vector flight requirements at the same time.

However, such a Lambert routine assumes that the thrust of the aircraft can be stopped. However, the present invention can not use the Lambert routine as it targets a vehicle that can not control the speed.

The Lambert routine calculates the required speed and flight path angle according to a predetermined required flight time, while the RRFPA calculates the flight path angle and flight time according to a predetermined speed. That is, the RRFPA uses the current speed instead of the flight time as an input value, and can obtain the required flight path angle and flight time with respect to the current speed.

The required speed vector can be constructed through the given required flight path angle and the applied input speed from the RRFPA, so that the increased required speed vector can be obtained. When the required flight path angle is obtained by applying the current speed, the current speed becomes the required speed. Thus, the magnitude of the velocity need not be controlled, and the flight path angles must be controlled to coincide with each other. That is, when the current speed is applied as an input, the speed vector required to send the aircraft to the desired point at the point of exhaustion of fuel is automatically automatically provided that the flight path angle of the current speed vector follows the required flight path angle by RRFPA. Is achieved.

Note that both the Lambert routine and the RRFPA rotate the Earth, so it is essential to perform repetitive calculations. In other words, strictly speaking, the required speed or flight path angle before convergence by the two routines is meaningless, and only the converged values have meaning as "required values" in order to reach a desired point.

In FIG. 3, V _r represents a required velocity, γ _r represents a required flight path angle, and φ represents a range angle between the vectors r ₁ and r ₂ . In order for the aircraft to move from one point r ₁ to another point r ₂ in the earth's gravitational field, the aircraft must simultaneously satisfy the required speed V _r and the required flight path angle γ _r at r ₁ .

In the following, an estimation method related to deriving the required speed and the required flight path angle will be described through Equations 3 to 8. Detailed derivation methods of the following Equations 3, 6 and 7 are described in 'P. Zarchan "Tactical and Strategic Missile Guidance.", 2nd Edition, AIAA series, 1994 '.

When the elliptical orbit by the velocity vector V _r at the initial position r ₁ passes r ₂ point, the following equation (3) is established.

Where μ is the universal gravitation constant.

Equation 3 is summarized as Equation 4 below with respect to cosγ _r .

here,

to be.

If both sides of the equation (4) are squared and the equation (4) is summarized with respect to cosγ _r using the root formula of the quadratic equation, the required flight path angle can be obtained as shown in Equation 5 below. Equation 5 below derives an equation for calculating the required flight path angle from the required speed calculation equation used in the Lambert routine.

The firing angle φ and the flight path angle t _f are shown in Equations 6 and 7, respectively.

In addition, the minimum speed V _min for reaching the range angle φ is given by Equation 8 below by the optimum flight path angle γ _opt .

The required flight path angle γ _r with respect to the arbitrary speed V can be obtained by substituting the speed V into Equation 5 instead of the required speed V _r . However, because the earth rotates, a two-point boundary problem arises that cannot be solved at one time. Therefore, iterative calculation must be performed.

FIG. 5 is a flowchart illustrating a procedure of estimating a required flight path angle with respect to the speed V using Equations 5 to 8 above.

In the above procedure, the speed V is given as an input value. The speed V may be the speed of the vehicle.

First, V _min is calculated using the above equation (S210).

If the input value, that is, the speed applied is less than a certain value, it is impossible to calculate the required flight path angle. Therefore, in order to solve this problem, V _min as described above needs to be calculated. In addition, when the speed V is close to the minimum speed V _min , the number of iterations increases rapidly and the solution does not converge. Thus, a predefined threshold α is introduced to increase the convergence performance. In addition, it is necessary to calculate the γ _r, even if V is less than the sum of the V _min and V α is defined as Equation (9) below.

That is, if V is not greater than the sum of V _min and α (S220), V is the sum of V _min and α (S230). Due to Equation 9, the required flight path angle can always be obtained from the RRFPA. For example, when α is 50 m / s, a solution converged by 10 or fewer iterations can be obtained.

Next, γ _r and t _f are estimated based on the V (S240 and S250).

Next, it is checked whether t _f converges (S260). If t _f does not converge, the procedure is repeated to perform again from the estimation step S210 of V _min . If t _f converges the procedure is terminated and the estimated γ _r and t _f are derived as a result of this procedure.

Next, look at the flight path angle control method for entering the elliptical track in the parking track according to an embodiment of the present invention.

That is, a flight path angle control method applied in a section from r ₀ to r ₁ in order to reach an aircraft at r ₂ point in FIG. 3 will be described.

When the required flight path angle γ _r with respect to the speed of the aircraft is obtained using the above-described RRFPA, when the current flight path angle γ of the vehicle achieves γ _r , the desired point r ₂ is achieved without controlling the speed of the vehicle. The velocity vector V _r required to reach can be obtained. However, in general, when the speed increases very rapidly, γ _r with respect to the current speed also increases rapidly, so it is not easy to design to directly follow γ _r .

Therefore, in the present embodiment, a pseudo velocity V _p as shown in Equation 10 below is introduced and used as the input velocity of the RRFPA. That is, an increase demand velocity vector V _gp corresponding to V _P is obtained to generate an instruction for directing thrust in this direction.

Where V is the current velocity of the vehicle and ΔV is the velocity parameter determined by the simulation.

The ΔV may be about 2% of the maximum speed of the vehicle.

In addition, the RRFPA used in the present embodiment uses the following Equation 11 among two required flight path angle equations according to Equation 5 above.

FIG. 6 is a diagram illustrating a relationship between a velocity vector, a flight path angle, and a velocity-to-go vector of a vehicle.

In FIG. 6, the pseudo speed V _p , the required speed V _r, and the current speed V required to reach the target point r ₂ are illustrated, and flight path angles γ _rp , γ _r, and γ according to the respective speeds are illustrated. 6, the increase request rate vectors V _g and V _gp are the following Equations 12 and 13, respectively.

The purpose of this flight path angle control is to make the current speed vector V coincide with the required speed vector V _r , that is, to make V _g equal to zero. However, while the speed V increases rapidly, and correspondingly, the required flight path angle γ _r also increases rapidly, the response time of γ is very slow. Therefore, it is practically impossible to direct V _g to zero, that is, to make y be y _r , with the thrust of the vehicle in the direction of the vector V _g .

Therefore, in the present embodiment, instead of V _g , V _gp by γ _rp considering a lead angle is used.

7 is a flowchart illustrating a flight path angle control procedure for entering an elliptical track in a parking track according to the present embodiment.

First, γ _rp is estimated by the RRFPA described above with the pseudo velocity V _p as an input (S310).

Next, V _p and V _gp are estimated based on the γ _rp (S320 and S330).

Finally, an instruction for directing thrust in the V _gp direction is transmitted (S340).

Next, look at the flight path angle control method for entering the circular orbit in the elliptical orbit according to an embodiment of the present invention.

That is, when the second kick motor is ignited when the vehicle reaches r ₂ of FIG. 4, when the vehicle is located at r ₃ , the speed V of the vehicle becomes V _c , and the velocity vector V of the vehicle It is the purpose of the present flight path angle control method to make the flight path angle γ be γ _c . Where γ _c is zero.

The transition of the elliptical trajectory in the circular orbit which is the above-described parking trajectory does not matter the speed size when the target point is reached. However, when the circular orbit enters the elliptical orbit, the magnitude of the entry speed also becomes a limiting condition. This requires that the desired speed V _c of the vehicle and the speed V _cap obtained when the fuel is exhausted be the same. That is, it can be assumed that V _c = V _cap .

In addition, as shown in FIG. 3, when the vehicle transitions from the circular orbit to the elliptical orbit, the free flight section is long. On the other hand, the free flight section is not shown in FIG. 4, which shows a case in which the vehicle enters the circular orbit from the elliptical orbit. Strictly speaking, this is not a lack of free flight, but rather a very short one. That is, the vehicle reaches the desired point r ₃ at the same time as the fuel is exhausted.

The control method uses RRFPA, and the pseudo velocity V _p of Equation 9 is used as an input of the RRFPA, but to calculate the required flight path angle, the following Equation 14 is obtained from the two solutions given in Equation 5. This is used.

The range angle? Is given by the following equation (15).

In other words, the embodiment differs from the case of the transition from the circular orbit to the elliptic orbit using the equation (14) instead of the equation (11) as the calculated flight path angle.

In addition, in FIG. 4, when the flying object approaches r ₃ and the angle φ decreases and becomes too small, the RRFPA may operate in an area that does not converge. Thus, the phi is limited to be above a sufficiently small predefined threshold. The restriction may be as shown in Equation 16 below. When entering the elliptical orbit into the circular orbit, the process of Equation 16 below should be added over the V _min estimating process (S210) of FIG. 3.

As shown in FIG. 5, as the φ decreases, the flight time of the vehicle also decreases. This causes the required flight path angle γ _{r according} to Equation 14 to be close to 0, which means γ _c = 0, which is one of the requirements for the circular orbit. Therefore, if the aircraft flies while controlling the flight path angle to achieve the required flight path angle γ _r , the speed V becomes V _c at the point of exhaustion of the fuel, and the flight path angle γ of the aircraft becomes γ _c to achieve the circular orbit. do.

Fig. 8 is a diagram showing γ _rp and the direction V _gp in which thrust should be applied in a region where φ is small.

Care must be taken to properly select the position of r ₂ in FIG. If the size of r ₂ is too small or large, γ cannot be zero. Preferably, after drawing the largest ellipse within the fuel range of the first kick motor, one point on the ellipse smaller than the size of r ₃ may be selected as the position of r ₂ . In addition, it is important that r ₂ is appropriately set so that the exhaustion time of the second kick motor is r ₃ , and the combustion time and the elliptic trajectory of the fuel may be considered.

9 to 11 are diagrams showing computer simulation results for a case where the vehicle enters an elliptical orbit into a circular orbit.

FIG. 9 is a diagram showing the induction command obtained for the vehicle to apply thrust in the direction of the vector V _gp over time.

FIG. 10 is a diagram illustrating flight path angle γ and required flight path angle γ _r of the air vehicle as time elapses. As shown in FIG. 10, the flight path angle γ of the speed vector of the vehicle closely follows the required flight path angle γ _r as the exhaustion time approaches. Therefore, at the time of exhaustion, it can be seen that γ achieves γ _c so that the condition for entering the orbit is satisfied. That is, γ = γ _r = γ _c = 0 at the point of exhaustion, and the speed V at the point of exhausting the fuel, of course V = V _r = V _c = Satisfy V _cap .

FIG. 11 is a diagram illustrating altitude of the vehicle according to time. It can be seen that the altitude of the vehicle remains constant after the fuel exhaustion time.

The above-described RRFPA and flight trajectory angle control method may be used in a vehicle including a control unit and a thrust unit.

The control unit performs the RRFPA and flight trajectory angle control method according to the embodiment of the present invention described above. The vehicle generates a guide command for performing orbital transition based on the performance, and transmits the guide command to the thrust unit.

The thrust unit receives the induction command to generate a thrust.

The method according to the invention described thus far can be implemented in software, hardware, or a combination thereof. For example, the method according to the present invention may be stored in a storage medium (eg, mobile terminal internal memory, flash memory, hard disk, etc.) and may be stored in a processor (eg, mobile terminal internal microprocessor). It may be implemented as codes or instructions in a software program that can be executed by.

In the above description of the preferred embodiments of the present invention by way of example, the scope of the present invention is not limited only to these specific embodiments, the present invention is in various forms within the scope of the spirit and claims of the present invention Can be modified, changed, or improved.

Claims (13)

In the method for performing the trajectory transition of the vehicle that can not control the speed,
Estimating a minimum speed for reaching the firing angle;
Making the sum as the value of the input speed if the input speed is not greater than the sum of the estimated minimum speed and a predefined speed threshold;
Estimating a required flight path angle based on the input speed;
Estimating a converged required flight path angle based on the input speed and the calculated required flight path angle. The method of claim 1,
Estimating a velocity-to-go increase demand vector based on the input speed and the converged required flight path angle by a difference between the required speed vector and the current speed vector; And
Orienting the thrust in the direction of the increased demand velocity vector. 3. The method according to claim 1 or 2,
The input speed is the current velocity of the vehicle, and when the range angle is less than a predefined range threshold, the range threshold is used as the range angle, and the trajectory transition is a point of a circular orbit at one point of the ellipse orbit. Orbital transition method of the aircraft, characterized in that the transition. 3. The method according to claim 1 or 2,
The orbital transition method of the vehicle, characterized in that for varying the speed that is the basis of the input speed according to the current trajectory of the vehicle. The method of claim 4, wherein
If the vehicle is moving from one point of the parking track to one point of the elliptical orbit, the pseudo speed sum of the current speed of the vehicle and the speed parameter based on the simulation is used as the input speed.
And the pseudo velocity of the vehicle is used as the input speed when the vehicle is in transition from one point of an ellipse orbit to a point of circular orbit. 6. The method of claim 5,
When the vehicle is in the transition of the trajectory from one point of the elliptic orbit to one point of the circular orbit, if the range angle is less than a predefined range threshold value, the range threshold is set as the range angle. Orbital transition method. A controller for generating and transmitting an instruction to perform an orbital transition of the vehicle; And
And a thrust unit configured to generate a thrust by receiving an induction command of the controller, wherein the vehicle cannot control the speed, and the controller estimates the required flight path angle based on the speed of the vehicle, and estimates the required flight. And estimating an increase request speed vector based on a path angle to generate an instruction to move the vehicle according to the increase request speed vector. The method of claim 7, wherein the control unit,
Estimate the minimum speed to reach the firing angle,
If the input speed is not greater than the sum of the estimated minimum speed and the predefined speed threshold, the sum is taken as the value of the input speed,
Estimate the required flight path angle based on the input speed,
And judging whether the estimated required flight path angle converges, and when the estimated requested flight path angle converges, using the estimated requested flight path angle as a new required flight path angle. The method of claim 8,
And the input speed is a pseudo speed obtained by adding the current speed of the vehicle and a speed parameter based on the simulation, and the track transition is an orbital transition from one point of the parking track to one point of the elliptical track. The method of claim 9,
The input speed is the current speed of the vehicle, and the control unit uses the range threshold as the range angle when the range angle is smaller than a predefined range threshold, and the trajectory transition is a circular orbit at one point of the ellipse orbit. An aircraft characterized by an orbital transition to one point. The method of claim 8,
And a different speed reference depending on the position of the vehicle as a base of the input speed. 12. The method of claim 11,
If the vehicle is moving from one point of the parking track to one point of the elliptical orbit, the pseudo speed sum of the current speed of the vehicle and the speed parameter based on the simulation is used as the input speed.
And the pseudo velocity of the vehicle is used as the input speed when the vehicle is moving from one point of an ellipse orbit to a point of a circular orbit. The method of claim 12,
And when the vehicle is in a trajectory transition from one point of an ellipse orbit to a point of a circular orbit, the smaller of the range angle and a predefined range threshold value as the range angle.

Images