Arrow-carrying cross-medium aircraft flight trajectory planning method and application

Abstract

The application relates to a flight trajectory planning method of a rocket-borne cross-medium aircraft and application, and belongs to the field of aircraft trajectory technology. The method is as follows: a motion model of an aircraft longitudinal plane is established; after the aircraft is released from a rocket, the aircraft enters an out-of-segment, and the trajectory parameters at the end of the release of the rocket are input as initial parameters of the out-of-segment; according to the initial release height of the aircraft and the out-of-segment requirement, the trajectory inclination angle of the out-of-segment of the aircraft is determined; trajectory simulation is carried out by adopting the trajectory inclination angle; after the aircraft successfully out-of-segments, the aircraft enters a gliding segment, and the trajectory parameters at the end of the out-of-segment are input as initial parameters of the gliding segment; the trajectory inclination angle of the gliding segment of the aircraft is determined, and the height and speed of the aircraft in the gliding segment are continuously reduced until the water entry requirement is met. The application meets the flight indexes and requirements among the segments by designing reasonable trajectory inclination angles, and the cross-medium aircraft is rapidly deployed to corresponding sea areas in a short time to realize long-range and fast-response cross-domain strikes.

Description

Technical Field

[0001] This invention belongs to the field of aircraft ballistics technology, specifically relating to a method and application for flight trajectory planning of a rocket-borne cross-medium aircraft. Background Technology

[0002] With numerous islands surrounding my country, a long coastline, and a vast exclusive economic zone, aircraft with characteristics such as long range, strong penetration capability, good maneuverability, difficulty in interception, and the ability to strike targets across media and water play a very important role in enhancing the diversified combat capabilities of my country's navy and air force.

[0003] Launch vehicles, launched via rockets, are characterized by flexible deployment and launch, high speed, long range, and strong maneuverability and penetration capabilities. They can quickly strike various long-range targets and complete auxiliary military tasks such as surveillance, reconnaissance, and attack, making them a current research hotspot in the aerospace field.

[0004] After the rocket is launched to the target area, the cross-medium aircraft separates from it. It has the ability to be rapidly deployed in the air and has strong stealth after entering the water. It can form a letter-shaped combat coordination with underwater submarines and can complete information exchange and cross-domain collaborative search operations with surface ships and drones.

[0005] Deploying cross-medium aircraft via rocket launchers can significantly enhance their maneuverability and penetration capabilities, as well as their long-range rapid response capabilities. Rocket launches can extend the flight path of cross-medium aircraft to over 400 km, which has a positive effect and significant military value in expanding the operational radius of aircraft carriers and enhancing maritime defense and integrated air-sea strike capabilities.

[0006] While there is a certain research foundation for rocket-borne vehicles and high-altitude gliding cross-medium vehicles, a complete study of the overall flight trajectory of rocket-borne cross-medium vehicles from launch and deployment to water entry is lacking. Existing technologies only focus on single stages, such as the rocket launch phase or the air-to-water drop phase. Current booster-separation technologies generally employ horizontal deployment, which does not address extreme angle situations in terms of ballistics. When the rocket-borne vehicle separates from the rocket during the rocket's vertical descent deceleration phase, the post-release trajectory angle is close to 90°, with an almost vertical downward attitude. Existing horizontal deployment methods cannot achieve a rapid and stable recovery from this attitude. Furthermore, current technologies lack detailed and comprehensive research on the overall flight trajectory of rocket-borne vehicles transported hundreds of kilometers away.

[0007] For the reasons mentioned above, it is necessary to conduct corresponding research on the overall flight trajectory of rocket-borne cross-medium vehicles to ensure the rationality of the overall trajectory after the vehicle separates from the rocket. This requires not only to achieve safe recovery but also to ensure that the vehicle has a safe cross-medium water entry angle and velocity. Summary of the Invention

[0008] The technical problem to be solved:

[0009] To overcome the shortcomings of existing technologies, this invention provides a flight trajectory planning method for a rocket-borne cross-medium aircraft. The cross-medium aircraft folds its wings and places them within the rocket, enhancing its long-range flight capability and expanding its operational area. After the rocket decelerates, the aircraft is released from within it. When the rocket separates from the aircraft, it is in the deceleration phase of the rocket's vertical descent. After release, the aircraft's trajectory inclination angle is close to 90°, and its attitude is almost vertically downward. This invention plans the aircraft's trajectory for the recovery phase, gliding phase, water entry phase, and the transition trajectories between these phases. By designing reasonable trajectory inclination angles, the method meets the flight indicators and requirements between each phase, enabling rapid deployment of the cross-medium aircraft to the corresponding sea area for long-range, rapid-response, cross-domain strikes.

[0010] The technical solution of this invention is: a flight trajectory planning method for a rocket-borne cross-medium vehicle, the specific steps of which are as follows:

[0011] Establish a motion model of the aircraft's longitudinal plane;

[0012] After the spacecraft is released from the rocket, it enters the recovery phase, and the ballistic parameters at the end of the rocket release are input as the initial parameters for the recovery phase.

[0013] Based on the initial release altitude and recovery requirements of the aircraft, a two-segment parabola is used as the flight curve to determine the trajectory inclination angle of the aircraft's recovery segment. The trajectory inclination angle changes continuously and differentiably with time. The trajectory inclination angle is used to perform trajectory simulation. If the recovery requirements are met, the next step is performed. If not, the trajectory inclination angle is re-determined.

[0014] After the aircraft successfully recovers, it enters the glide phase. The ballistic parameters at the end of the recovery phase are input as the initial parameters for the glide phase.

[0015] Determine the trajectory inclination angle of the aircraft during the glide phase, so that the altitude and speed of the aircraft during the glide phase are continuously reduced until the requirements for water entry are met;

[0016] After the glide phase, the spacecraft enters the water entry phase. The ballistic parameters at the end of the glide phase are input as the initial parameters for the water entry phase. The retro-rocket is ignited to ensure that the spacecraft's water entry angle is between -30° and -80° and the water entry speed is not higher than 50m / s. If the requirements are met, the design ends; otherwise, the process returns to the previous step.

[0017] A further technical solution of the present invention is: the motion model formula of the longitudinal plane of the aircraft is as follows:

[0018]

[0019]

[0020]

[0021]

[0022] θ=θ * (t)

[0023]

[0024]

[0025]

[0026]

[0027]

[0028] In the formula: v is the flight speed of the aircraft; T is the thrust of the aircraft; X is the drag of the aircraft; α is the angle of attack of the aircraft; m is the mass of the aircraft; θ is the trajectory angle of the aircraft; n y This is a normal overload; For normal overload at an angle of attack of α; n y,α＝0 The normal overload at zero angle of attack; x is the horizontal distance of the aircraft from the initial point of each segment; y is the altitude of the aircraft; Y α The lift is at an angle of attack α; The pitch rudder deflection angle is δ z The lift below; The pitching moment is at an angle of attack of α; The pitch rudder deflection angle is δ z Pitching moment; C Yα This is the derivative of the lift coefficient with respect to the angle of attack; is the derivative of the lift coefficient with respect to the pitch deflection angle; S is the reference area of ​​the aircraft;

[0029] A further technical solution of the present invention is that the recovery requirements include minimum recovery safety height, maximum overload, recovery speed, angle, and safety separation requirements for the lift limit.

[0030] A further technical solution of the present invention is: the calculation formula for the two-segment parabola is as follows:

[0031]

[0032] Where y1 is the first segment of the parabola and y2 is the second segment of the parabola. θ0 is the initial trajectory inclination angle, θ1 is the designed maximum trajectory inclination angle, t0 is the initial moment of the recovery phase, t1 is the moment when the designed maximum trajectory inclination angle θ1 is reached, and t2 is the final moment of the recovery phase.

[0033] A further technical solution of the present invention is as follows: the trajectory inclination angle of the recovery segment is a curve that changes with time, including two parabolas. In the first parabola, the trajectory inclination angle gradually increases from close to -90° to a positive value until it reaches the maximum designed inclination angle. In the second parabola, the trajectory inclination angle gradually decreases and eventually becomes 0. According to the calculation formula of the two parabolas, in order to ensure a smooth transition of the angle and the continuous differentiability of the entire curve, the vertices of the two parabolas coincide and are the maximum trajectory inclination angle of the recovery segment. The recovery time is controlled within 150 seconds.

[0034] A further technical solution of the present invention is: the requirement to meet the water entry requirements means that at the end of the gliding phase, the speed shall not exceed 180m / s and the altitude shall not exceed 100m.

[0035] A further technical solution of the present invention is: the trajectory of the gliding segment is determined by the trajectory inclination angle of the gliding segment, which linearly decreases from 0 at the end of the recovery segment to a fixed value within 2 seconds and remains thereuntil the end of the gliding segment, with the gliding time controlled within 220 seconds.

[0036] A flight trajectory planning method for rocket-borne cross-medium aircraft is applied to aircraft that need to perform separation and recovery missions as well as cross-medium aircraft that need to enter water.

[0037] An electronic device includes at least one processor and a memory communicatively connected to the at least one processor; wherein the memory stores a computer program executable by the at least one processor, the computer program being executed by the at least one processor to enable the at least one processor to execute the flight trajectory planning method for a rocket-borne transmedium vehicle.

[0038] A computer-readable storage medium storing computer instructions that enable a processor to execute the aforementioned method for flight trajectory planning of a rocket-borne transmedium spacecraft.

[0039] Beneficial effects

[0040] The beneficial effects of this invention are as follows: This invention targets rocket-borne cross-medium spacecraft, planning the trajectory of each stage after separation from the rocket. It provides a complete trajectory planning method for the entire flight process from separation to water entry, including the recovery trajectory after separation and the gliding trajectory before water entry. The proposed two-stage subparabolic trajectory design method for the recovery trajectory can increase the recovery altitude to 7500m, meeting the requirements for safe separation and ensuring safe recovery. The gliding trajectory planning controls the spacecraft's altitude within 100m and speed within 180m / s, providing a foundation for the spacecraft's entry into the water. Finally, the angle before water entry is controlled at -72° and the speed at 33.3m / s, satisfying the cross-medium water entry conditions. The method proposed in this invention can quickly send a spacecraft to a target area hundreds of kilometers away via rocket for cross-medium combat strikes, enhancing the spacecraft's long-range, rapid-response, cross-domain penetration capability. Attached Figure Description

[0041] Figure 1 A flowchart for designing a flight trajectory planning method for a rocket-borne cross-medium vehicle;

[0042] Figure 2 This is a schematic diagram of the drone's structure.

[0043] Figure 3 A schematic diagram illustrating the design of the trajectory inclination angle change during the recovery phase;

[0044] Figure 4 The example shows the trajectory of the aircraft during its recovery phase.

[0045] Figure 5 The example shows the glide trajectory of the aircraft.

[0046] Figure 6 The velocity curve of the aircraft during the gliding phase in the embodiment;

[0047] Figure 7 The example shows the ballistic trajectory of the aircraft during its water entry phase.

[0048] Figure 8 The velocity curve of the aircraft during its water entry phase is shown in the example.

[0049] Figure 9 The example shows the attitude angle curve of the aircraft's water entry section. Detailed Implementation

[0050] The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the invention, and should not be construed as limiting the invention.

[0051] Addressing the limitations of existing horizontal launch trajectories in achieving the rapid and stable recovery of a vehicle using the vertical launch method described in this invention, and the lack of detailed and comprehensive research on the overall flight trajectory of rocket-borne vehicles transported hundreds of kilometers away, this invention proposes a flight trajectory planning method for rocket-borne cross-medium vehicles. Starting with an analysis of the attitude and velocity of the cross-medium vehicle after release from the rocket, the method designs the trajectory inclination angles for both the recovery and gliding phases. It employs a retro-propulsion rocket to ensure safe deceleration and water entry, and plans the overall flight trajectory after separation from the rocket, ensuring safe recovery and a safe cross-medium water entry angle and velocity. The method proposed in this invention can quickly deliver a vehicle to a target area hundreds of kilometers away via rocket for cross-medium combat strikes, enhancing the vehicle's long-range, rapid-response, cross-domain penetration capabilities.

[0052] The flowchart of a flight trajectory planning method for a rocket-borne cross-medium aircraft in this embodiment is as follows: Figure 1 As shown, the trajectory includes three phases: recovery, gliding, and water entry. The steps are as follows:

[0053] Step 1: Establish the motion model of the aircraft in the longitudinal plane:

[0054]

[0055]

[0056]

[0057]

[0058] θ=θ * (t)

[0059]

[0060]

[0061]

[0062]

[0063]

[0064] In the formula: v is the flight speed of the aircraft; T is the thrust of the aircraft; X is the drag of the aircraft; α is the angle of attack of the aircraft; m is the mass of the aircraft; θ is the trajectory angle of the aircraft; n y This is a normal overload; For normal overload at an angle of attack of α; n y,α＝0The normal overload at zero angle of attack; x is the horizontal distance of the aircraft from the initial point of each segment; y is the altitude of the aircraft; Y α The lift is at an angle of attack α; The pitch rudder deflection angle is δ z The lift below; The pitching moment is at an angle of attack of α; The pitch rudder deflection angle is δ z Pitching moment; C Yα This is the derivative of the lift coefficient with respect to the angle of attack; is the derivative of the lift coefficient with respect to the pitch control angle; S is the reference area of ​​the aircraft; different aircraft use different parameters, and the structural diagram of the aircraft in this embodiment is shown below. Figure 2 As shown, the relevant parameters are shown in Table 1.

[0065] Table 1. Relevant parameters of a certain type of transmedium aircraft.

[0066]

[0067] Step 2: After the spacecraft is released from the rocket, it enters the recovery phase. The ballistic parameters at the end of the rocket release are input as the initial parameters for the recovery phase. In this embodiment, the terminal parameters of the rocket, which are also the initial parameters of the spacecraft's recovery phase, are: initial altitude of 7000m, initial velocity of 150m / s, and initial trajectory inclination of -85°.

[0068] Step 3: Based on the initial release altitude and recovery requirements of the aircraft, including the minimum safe recovery altitude, maximum overload, recovery speed, angle, service ceiling and other safe separation requirements, design the ballistic inclination angle of the aircraft recovery segment, and perform ballistic simulation. If the requirements are met, proceed to the next step; if not, redesign the ballistic inclination angle.

[0069] Specifically, a two-segment parabola is used as the flight curve to determine the trajectory inclination angle of the aircraft's recovery phase. This trajectory inclination angle is continuously differentiable over time. The formula for the two-segment parabola is as follows:

[0070]

[0071] Where y1 is the first segment of the parabola and y2 is the second segment of the parabola. θ0 is the initial trajectory inclination angle, θ1 is the designed maximum trajectory inclination angle, t0 is the initial moment of the recovery phase, t1 is the moment when the designed maximum trajectory inclination angle θ1 is reached, and t2 is the final moment of the recovery phase.

[0072] Step 4: After the aircraft successfully recovers, it enters the glide phase. Input the ballistic parameters at the end of the recovery phase as the initial parameters for the glide phase.

[0073] Step 5: Design the trajectory inclination angle of the aircraft during the glide phase to meet the requirements that the aircraft continuously decreases in altitude and speed during the glide phase and prepares for the water entry phase;

[0074] Meeting the water entry requirements means that at the end of the gliding phase, the speed must not exceed 180m / s and the altitude must not exceed 100m.

[0075] Step 6: After the glide phase, the aircraft enters the water entry phase. Input the ballistic parameters at the end of the glide phase as the initial parameters for the water entry phase. Ignite the retro-rockets to ensure that the aircraft has a suitable water entry angle and speed. If the requirements are met, the design ends; otherwise, return to step 5.

[0076] Specifically, the aircraft's water entry angle should be between -30° and -80°, and the water entry speed should not exceed 50m / s. If the requirements are met, the design is complete; otherwise, return to the previous step.

[0077] In this embodiment, the trajectory planning method for a rocket-borne cross-medium vehicle involves designing the recovery phase trajectory, which is a curve showing how the trajectory inclination changes over time. Figure 3 As shown, θ0 is the initial trajectory inclination angle of the aircraft's recovery phase, θ1 is the maximum recovery trajectory inclination angle, t0 is the initial time of the recovery phase, t1 is the time when the trajectory inclination angle reaches its maximum value, and t2 is the recovery phase time. The trajectory inclination angle changes with time as two parabolas. In the first parabola, the trajectory inclination angle gradually increases from close to -90° to a positive value until it reaches the maximum designed inclination angle. In the second parabola, the trajectory inclination angle gradually decreases and eventually becomes 0. To ensure a smooth transition of the angle and the continuous differentiability of the entire curve, the vertices of the two parabolas coincide and represent the maximum trajectory inclination angle of the recovery phase, corresponding to time t1. The recovery time t2 is controlled within 150 seconds. The design of the trajectory inclination angle includes the design of the values ​​of θ1, t1, and t2.

[0078] In this embodiment, the trajectory planning method for a rocket-borne transmedium vehicle involves designing the trajectory inclination angle. The trajectory inclination angle linearly decreases from 0 at the end of the recovery phase to a fixed value within 2 seconds and remains thereuntil the end of the glide phase. The glide time is controlled within 220 seconds.

[0079] In this embodiment, the relevant parameters required by the specific cross-medium spacecraft are shown in Table 1. The initial altitude of the recovery stage is 7000m, the initial velocity is 150m / s, and the initial trajectory inclination is -85°. The designed θ1 is 15°, t1 is 12s, and t2 is 110s. The rocket retro-thrust force of the water entry stage is -14000N, and the retro-thrust time is 3s.

[0080] This embodiment discloses an electronic device, including at least one processor and a memory communicatively connected to the at least one processor; wherein the memory stores a computer program executable by the at least one processor, the computer program being executed by the at least one processor to enable the at least one processor to execute the flight trajectory planning method for a rocket-borne transmedium vehicle.

[0081] This embodiment provides a computer-readable storage medium that stores computer instructions. These computer instructions are used to enable a processor to implement the flight trajectory planning method for a rocket-borne cross-medium spacecraft when executed.

[0082] This embodiment presents a flight trajectory planning method for rocket-borne cross-medium aircraft, applicable to aircraft requiring separation and recovery missions, as well as cross-medium aircraft with water entry requirements. The simulation results of this embodiment are as follows: Figures 4-9 As shown in the figure, the ballistic trajectory of the cross-medium aircraft designed in this invention enables the aircraft to achieve stable recovery and high-altitude gliding. The minimum recovery altitude is 5200m, and the recovery altitude is 7500m. At the end of the gliding phase, the aircraft reaches an altitude of 70m and a speed of 155m / s, which meets the requirements for entering the water phase. Before entering the water, the aircraft's speed is 33.3m / s, and its attitude angle is -72°, which meets the requirements for load reduction.

[0083] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention without departing from the principles and spirit of the present invention.

Claims

1. A method for planning the flight trajectory of a rocket-borne cross-medium vehicle, characterized in that... The specific steps are as follows: Establish a motion model of the aircraft's longitudinal plane; After the spacecraft is released from the rocket, it enters the recovery phase, and the ballistic parameters at the end of the rocket release are input as the initial parameters for the recovery phase. Based on the initial release altitude and recovery requirements of the aircraft, a two-segment parabola is used as the flight curve to determine the trajectory inclination angle of the aircraft's recovery segment. The trajectory inclination angle changes continuously and differentiably with time. The trajectory inclination angle is used to perform trajectory simulation. If the recovery requirements are met, the next step is performed. If not, the trajectory inclination angle is re-determined. After the aircraft successfully recovers, it enters the glide phase. The ballistic parameters at the end of the recovery phase are input as the initial parameters for the glide phase. Determine the trajectory inclination angle of the aircraft during the glide phase, so that the altitude and speed of the aircraft during the glide phase are continuously reduced until the requirements for water entry are met; After the glide phase, the spacecraft enters the water entry phase. The ballistic parameters at the end of the glide phase are input as the initial parameters for the water entry phase. The retro-rocket is ignited to ensure that the spacecraft's water entry angle is between -30° and -80° and the water entry speed is not higher than 50m / s. If the requirements are met, the design ends; otherwise, return to the previous step. The formula for calculating the two-segment parabola is as follows: in, This is the first segment of the parabola. This is the second segment of the parabola. , , The initial trajectory inclination angle, To achieve the maximum designed ballistic inclination angle, To modify the initial time of the segment, To achieve the maximum designed ballistic inclination angle At that moment, This is the final moment before the revised section is completed.

2. The flight trajectory planning method for a rocket-borne cross-medium vehicle according to claim 1, characterized in that: The motion model formula for the longitudinal plane of the aircraft is as follows: In the formula: The speed of the aircraft; For the thrust of the aircraft; For the drag of the aircraft; Angle of attack for the aircraft; For the mass of the aircraft; The trajectory inclination angle of the aircraft; This is a normal overload; For normal overload on angle of attack The derivative; Normal overload under zero angle of attack conditions; This represents the horizontal distance of the aircraft from the initial point of each segment. The altitude of the aircraft; For lift against angle of attack The derivative; For lift, the pitch rudder deflection The derivative, For pitch moment angle of attack versus angle of attack The derivative; pitch moment versus pitch rudder deflection The derivative; This is the reference area of ​​the aircraft.

3. The flight trajectory planning method for a rocket-borne cross-medium vehicle according to claim 1, characterized in that: The recovery requirements include minimum safe recovery height, maximum overload, recovery speed, angle, and safe separation requirements for the lift limit.

4. The flight trajectory planning method for a rocket-borne cross-medium vehicle according to claim 1, characterized in that: The trajectory inclination angle of the recovery segment is a curve that changes over time, consisting of two parabolic segments. In the first parabolic segment, the trajectory inclination angle gradually increases from close to -90° to a positive value until it reaches the maximum designed inclination angle. In the second parabolic segment, the trajectory inclination angle gradually decreases until it becomes 0. According to the calculation formula of the two parabolic segments, in order to ensure a smooth transition of the angle and the continuous differentiability of the entire curve, the vertices of the two parabolic segments coincide and represent the maximum trajectory inclination angle of the recovery segment. The recovery time is controlled within 150 seconds.

5. The flight trajectory planning method for a rocket-borne cross-medium vehicle according to claim 4, characterized in that: Meeting the water entry requirements means that at the end of the gliding phase, the speed must not exceed 180m / s and the altitude must not exceed 100m.

6. The flight trajectory planning method for a rocket-borne cross-medium vehicle according to claim 5, characterized in that: The trajectory of the glide segment is determined by the trajectory inclination angle of the glide segment. This trajectory inclination angle decreases linearly from 0 at the end of the recovery segment to a fixed value within 2 seconds and remains thereuntil the end of the glide segment. The glide time is controlled within 220 seconds.

7. A transmedium-based aircraft, characterized in that, The separation and recovery mission, or the water entry mission, is accomplished using the flight trajectory planning method for rocket-borne cross-medium aircraft as described in any one of claims 1-6.

8. An electronic device, characterized in that: It includes at least one processor and a memory communicatively connected to the at least one processor; wherein the memory stores a computer program executable by the at least one processor, the computer program being executed by the at least one processor to enable the at least one processor to perform the flight trajectory planning method for a rocket-borne transmedium vehicle according to any one of claims 1-6.

9. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores computer instructions that enable a processor to implement the flight trajectory planning method for a rocket-borne transmedium vehicle as described in any one of claims 1-6.

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