An aircraft emergency parachute system and method capable of adjusting the angle of deployment

Abstract

This invention relates to an aircraft emergency parachute system with adjustable launch angle, comprising a parachute pack, a rocket launcher, and a parachute compartment. The parachute compartment is located on the top of the aircraft fuselage and configured to house the rocket launcher and the parachute pack. The system also includes a gimbal mounted within the parachute compartment and comprising a launch rail having at least two degrees of freedom. The rocket launcher is mounted on the gimbal via the launch rail, allowing the launch axis of the rocket launcher to change with the movement of the launch rail. A controller is also included, located within the parachute compartment and electrically connected to the gimbal and the rocket launcher. The controller is configured to adjust the angle of the rocket launcher based on real-time aircraft attitude information. This invention also relates to a method for launching an emergency parachute based on aircraft attitude. This invention significantly expands the applicable aircraft types for traditional rocket-launched emergency parachutes.

Description

Technical Field

[0001] This invention relates to the field of aircraft emergency rescue, and more specifically to an aircraft emergency parachute system with adjustable launch angle and a method for launching an emergency parachute based on aircraft attitude. Background Technology

[0002] With the development of fixed-wing UAV technology, more and more new aerodynamic shapes and advanced control technologies require verification. However, new designs come with potential risks and may lose control or even crash during test flights due to unexpected malfunctions, weather conditions, or other reasons. To avoid losses caused by unexpected loss of control, more and more UAVs are choosing to be equipped with emergency parachute systems. When necessary, the emergency parachute can be deployed to slow down the aircraft and ensure a safe landing.

[0003] Currently, the mainstream method of parachute deployment is rocket-powered launching. However, whether it is a rocket-launched parachute produced by domestic companies and used in military equipment delivery, aircraft drag chute, or rocket and satellite recovery, its launch device adopts a fixed-angle launch design.

[0004] This fixed-angle launch method presents significant problems in practical applications. Specifically, for aircraft with special aerodynamic configurations such as fixed-wing aircraft with high-mounted horizontal stabilizers, their attitude is difficult to predict when they unexpectedly lose control. In such cases, if the emergency parachute is launched at a fixed angle, the parachute cable is highly likely to collide with, touch, or even become entangled in the vertical and horizontal stabilizers due to excessive aircraft attitude angles or high flight speeds. In this situation, the emergency parachute system actually puts the aircraft in a more unfavorable position, greatly increasing the probability of a crash. Therefore, in actual use, it is often necessary to increase restrictions on the flight attitude during parachute deployment, which greatly limits the application scenarios of emergency parachutes.

[0005] Therefore, current rocket-launched emergency parachutes for drones use a fixed launch angle, which fails to address the issue of adjusting the launch angle in real-time based on the aircraft's attitude when its trajectory is uncontrollable, thus preventing the cables from colliding and interfering with the aircraft structure (especially the tail). In other words, a solution is currently desired that allows for adjusting the emergency parachute launch angle according to the real-time attitude of the aircraft. Summary of the Invention

[0006] This invention addresses the problem that in existing fixed-angle rocket-launched emergency parachutes, the launch cable is prone to collision or entanglement with the aircraft structure, such as the high-mounted tail, when the aircraft loses attitude control. It proposes an emergency parachute system with an adaptively adjustable launch angle, which can launch the emergency parachute at a suitable angle relative to the fuselage based on the real-time attitude and speed of the aircraft in an emergency, thus solving the problem that traditional systems may interfere with the aircraft's control surfaces after launch.

[0007] Specifically, this aircraft emergency parachute system with adjustable launch angle includes a parachute pack, a rocket launcher, and a parachute compartment. The parachute compartment is located on top of the aircraft fuselage and is configured to house the rocket launcher and the parachute pack. The system also includes: a gimbal, which is installed inside the parachute compartment and includes a launch rail with at least two degrees of freedom. The rocket launcher is mounted on the gimbal via the launch rail, allowing the launch axis of the rocket launcher to change with the movement of the launch rail; and a controller, which is located inside the parachute compartment and electrically connected to the gimbal and the rocket launcher. The controller is configured to adjust the angle of the rocket launcher based on the real-time attitude information of the aircraft.

[0008] In an embodiment of the invention, the parachute compartment includes a partition that divides the interior space into a first compartment for accommodating a rocket launcher and a second compartment for accommodating a parachute, and the gimbal is vertically fixedly mounted on the partition.

[0009] More specifically, the partition has concave openings for the cables connecting the rocket launcher and the parachute to pass through.

[0010] In an embodiment of the invention, the parachute compartment further includes a parachute compartment cover, which covers the top of the parachute compartment and is made of a lightweight material that can be pierced or broken by the rocket launch device; the parachute compartment cover is provided with openings for cables connecting the parachute pack and the fuselage hoisting point to pass through.

[0011] In an embodiment of the invention, the gimbal includes a gyroscope having two degrees of freedom, and a launch rail is fixed to the gyroscope.

[0012] In an embodiment of the present invention, the controller integrates a gimbal control unit, an ignition control unit, and a power module. The gimbal control unit is configured to control the movement of the gimbal's slide rail, and the ignition control unit is configured to control the ignition of the rocket launch device.

[0013] Furthermore, the controller has a communication interface configured to interact with the aircraft's inertial navigation system and / or ground control station to receive real-time attitude information and remote parachute deployment commands. The controller is configured to calculate the safe launch angle based on the real-time attitude information.

[0014] Preferably, the communication interface is further configured to receive real-time speed information of the aircraft, wherein the calculation of the safe launch angle is based on both real-time attitude information and real-time speed information, so as to make the calculated safe launch angle more accurate.

[0015] This invention also relates to a method for launching an emergency parachute based on aircraft attitude, comprising the following steps: acquiring real-time attitude information of the aircraft; calculating a safe launch angle based on the real-time attitude information to prevent the emergency parachute cable launched by the rocket launch device from interfering with the aircraft tail; controlling the rotation of a gimbal configured to support the rocket launch device to adjust the launch axis of the rocket launch device to the safe launch angle, wherein the gimbal includes a launch rail for supporting the rocket launch device, the launch rail having at least two degrees of freedom; and after the rocket launch device is adjusted to the correct position, controlling the rocket launch device to ignite and launch the emergency parachute at the safe launch angle.

[0016] Furthermore, the steps for calculating the safe launch angle include calculating the minimum distance between the parachute system cables and the aircraft profile at different launch angles based on the rocket's exit velocity, the aircraft's speed, the length of the cable connecting the rocket and the parachute, and the inflation characteristics of the emergency parachute; and selecting the angle that makes the minimum distance greater than the safety threshold as the safe launch angle.

[0017] Additional features and advantages of the aircraft emergency parachute system with adjustable launch angle described herein will be set forth in the detailed description below, and will be recognized by those skilled in the art either by the following description or by practice of the embodiments described herein, including the detailed description below and the accompanying drawings. Attached Figure Description

[0018] With reference to the above objectives, the technical features of the present invention are clearly described in the following detailed description of the embodiments, and its advantages are apparent from the following detailed description with reference to the accompanying drawings, which illustrate preferred embodiments of the invention by way of example, without limiting the scope of the inventive concept.

[0019] Figure 1A-1D A schematic diagram of an emergency parachute launcher in the prior art is shown.

[0020] Figure 2 An exploded schematic diagram of the parachute compartment of an aircraft emergency parachute system with adjustable launch angle according to the present invention is shown.

[0021] Figure 3 It shows Figure 2 A front view of the rocket launcher in the parachute compartment.

[0022] Figure 4 It shows Figure 2 A side view of the rocket launcher in the parachute compartment.

[0023] Figure 5 A schematic diagram of the parachute compartment and sling points of an aircraft emergency parachute system with adjustable launch angle according to the present invention is shown.

[0024] Figure 6 It shows Figure 5 A 3D diagram of the suspension points.

[0025] Figure 7 A schematic diagram of the controller for an aircraft emergency parachute system capable of adjusting the launch angle according to the present invention is shown.

[0026] Figure 8 A flowchart illustrating the action determination process of the controller of an aircraft emergency parachute system capable of adjusting the launch angle according to the present invention is shown.

[0027] Figure 9 A control law model of a controller for an aircraft emergency parachute system capable of adjusting the launch angle according to the present invention is shown.

[0028] Figure 10 A schematic diagram of the attitude of an aircraft using an aircraft emergency parachute system with an adjustable launch angle according to the present invention is shown when the parachute is straightened.

[0029] Figure 11 A schematic diagram of the aircraft's attitude during parachute inflation is shown, using an aircraft emergency parachute system with an adjustable launch angle according to the present invention.

[0030] Figure Labels

[0031] 1. Airplane; 2. Lifting points; 100 parachute compartments; 101 First Cabin; 102 Second compartment; 110 partition; 111. Concave opening; 120 Parachute Canopy; 121 Opening; 130mm gimbal; 131 Gyroscope; 132 Launch rails; 200 cables; 300 rocket launcher; 400 controller. Detailed Implementation

[0032] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments, but this should not be construed as limiting the present invention in any way.

[0033] For clarity, in the following text, the same or similar parts are referred to by the same reference numerals, and for multiple identical parts, only one of them is exemplarily labeled.

[0034] Figure 1A-1DThe diagram sequentially illustrates the current mainstream rocket-powered parachute ejection methods, with the ejection process consisting of: rocket launch; parachute deployment and straightening; parachute inflation; and full parachute opening. For high-tail aircraft, there is a high probability that during parachute ejection, due to excessive aircraft attitude angles and high flight speeds, the ejected emergency parachute cables may impact, touch, or even become entangled in the vertical and horizontal tail fins, significantly increasing the probability of a crash.

[0035] To address this, the present invention designs an aircraft emergency parachute system capable of adjusting the launch angle, comprising: a gimbal installed inside the parachute compartment and including a launch rail having at least two degrees of freedom, wherein a rocket launcher is mounted on the gimbal via the launch rail, allowing the launch axis direction of the rocket launcher to change with the movement of the launch rail; and a controller located inside the parachute compartment and electrically connected to the gimbal and the rocket launcher, the controller being configured to adjust the angle of the rocket launcher based on the real-time attitude information of the aircraft.

[0036] Now refer to Figure 2 A schematic diagram of a parachute compartment 100 of an aircraft emergency parachute system with adjustable launch angle according to the present invention is shown. The parachute compartment 100 includes a compartment wall, as shown, consisting of a compartment wall base plate, three vertical walls, and a curved wall. The parachute compartment 100 also includes a partition 110, which, together with the compartment wall, divides the interior space into sections for accommodating a rocket launch device 300 (see Figure 100). Figure 3 The parachute compartment 100 comprises a first compartment 101 and a second compartment 102 for accommodating a parachute (not shown). More specifically, a recessed opening 111 is provided on the bulkhead 110 for the cable 200 connecting the rocket launcher and the parachute to pass through. The parachute compartment 100 also includes a compartment cover 120, which covers the top of the compartment and is made of a lightweight material that can be pierced or broken by the rocket launcher 300. The compartment cover 120 has an opening 121 through which the cable 200 connecting the parachute to the fuselage sling point passes. The parachute cable 200 extends through the opening 121 and connects to the fuselage sling point 2, such as... Figure 5 and Figure 6 As shown (in) Figure 5 Four suspension points are shown in the figure (2).

[0037] Reference Figure 3 and Figure 4The parachute compartment 100 of the aircraft emergency parachute system with adjustable launch angle according to the present invention includes a gimbal 130, which is vertically fixed on a partition 110 and includes a gyroscope 131 and a launch rail 132. The gyroscope 131 has two degrees of freedom, and the launch rail 132 is fixed to the gyroscope 131 such that the launch rail 132 rotates together with the gyroscope 131. A rocket launcher 300 is mounted on the launch rail 132 of the gimbal 130. The gyroscope 131 of the gimbal is rotatable, driving the launch rail 132 to rotate (e.g., from...). Figure 4 The rocket launcher 300 rotates clockwise and counterclockwise (as seen in the image), thereby adjusting the launch angle of the rocket launcher 300. During launch, the rocket launcher 300 is ejected along the launch rail 132.

[0038] To properly adjust the launch angle of the rocket launcher 300, the aircraft emergency parachute system with adjustable launch angle according to the present invention also includes a controller 400. The controller 400 is disposed inside the parachute compartment 100 and is electrically connected to the gimbal 130 and the rocket launcher 300.

[0039] In an embodiment of the invention, the controller 400 is connected to the aircraft via a bus and receives attitude and other parameter signals sent by the aircraft. The controller integrates a gimbal control unit, an ignition control unit, and a power module. The gimbal control unit is configured to control the movement of the gimbal's slide rail, and the ignition control unit is configured to control the ignition of the rocket launch device. Furthermore, the controller 400 has a communication interface configured to interact with the aircraft's inertial navigation system and / or ground control station to receive real-time attitude information and remote parachute deployment commands. The controller 400 is configured to calculate the safe launch angle based on the real-time attitude information. The communication interface is further configured to receive the aircraft's real-time velocity information. The calculation of the safe launch angle is based on both the real-time attitude information and the real-time velocity information to make the calculated safe launch angle more accurate.

[0040] The following details how the controller adjusts the rocket launcher to a safe launch angle.

[0041] Table 1 below shows the interface signal definitions for the communication interface to illustrate various specific interactions:

[0042] Table 1 Emergency Umbrella System Interface Definitions

[0043] Reference Figure 7 The diagram illustrates the controller architecture. The aircraft ground station receiver receives the "parachute deployment command" from the ground as one of the external trigger signals for the system. The aircraft's inertial navigation system provides real-time attitude data for the aircraft: pitch angle, roll angle, and yaw rate, providing a reference for gimbal angle compensation.

[0044] The controller comprises a gimbal controller and an ignition controller. Digital communication I / O receives external commands (parachute deployment commands) and real-time aircraft status data, distributing them to the gimbal controller and ignition controller. It also transmits emergency status signals. The gimbal controller receives aircraft attitude and gimbal angle feedback (from the gimbal gyroscope), calculates and outputs drive commands to the gimbal motors to adjust the gimbal's attitude, ensuring its pointing meets launch requirements. The gimbal gyroscope continuously monitors the gimbal's current attitude and angle, feeding it back to the gimbal controller to form a closed-loop angle control system, ensuring precise and stable gimbal attitude. The gimbal motors execute commands from the gimbal controller, driving the gimbal gyroscope to rotate and complete the angle adjustment. The ignition controller is responsible for the timing and logic control of rocket ignition. It receives parachute deployment commands and rocket status feedback, and outputs an ignition signal via the "rocket ignition switch" when safety conditions are met.

[0045] When the controller receives a remote parachute ejection command, it calculates the appropriate angle based on real-time aircraft parameters and controls the gimbal to deflect the rocket to the appropriate angle for launch. The action determination process is as follows: Figure 8 As shown.

[0046] gimbal control law design such as Figure 9 As shown, the system receives the target angle (safe launch angle) of the gimbal, processes it through the proportional circuit K, and sends it as the desired command to the comparator. The comparator compares the desired command with the actual angle of the gimbal to obtain the deviation Δθ. The deviation signal Δθ is input to the gimbal motor transfer function, which converts it into a motor drive command CMD to drive the gimbal to rotate. The actual angle of the gimbal is fed back to the comparator in real time, continuously correcting the deviation until the actual angle of the gimbal is basically consistent with the target angle. This completes the angle adjustment of the rocket launch device.

[0047] The following section details the method for obtaining the gimbal target angle, i.e., the safe launch angle.

[0048] 1. Calculate the angle θt1 of the parachute relative to the ground coordinate system when the parachute is fully extended.

[0049] See Figure 10 This illustrates the geometric relationship between the rocket launcher's launch and the parachute's straightening.

[0050] Let S_total_length be the total length of the rocket-driven parachute pack before inflation. Then we have Formula 1: ........................... (1) The time from rocket launch t0 to parachute straightening t1 is calculated according to Formula 2: ..................................(2) Vrocket is the rocket's exit velocity, which can be determined based on the characteristics of the selected rocket. The distance S traveled by the aircraft during time t1 t1飞行 As shown in Formula 3: ..............................(3) At the moment the parachute is straightened, the initial straightening angle θ of the parachute relative to the ground coordinate system is as shown in Formula 4: ..............................(4) The flight path θt1 can be determined based on constraints such as flight path St1, S rocket cable, and θ gimbal, as shown in Formulas 5 and 6: .......(5) .......................(6) 2. Calculate the initial inflation angle θ of the parachute body relative to the ground coordinate system during parachute inflation.

[0051] When the parachute is straightened, it is affected by air resistance (Fair) and the aircraft's forward velocity. The parachute is pulled backward, and airflow enters the parachute, causing it to inflate. Its motion is as follows: Figure 11 As shown

[0052] The initial inflation angle θ of the umbrella relative to the ground coordinate system is as shown in Formula 7: .........................(7) The θ design inflation is a characteristic of the emergency parachute itself and needs to be calibrated according to the emergency parachute at different forward velocities.

[0053] In the blue triangle at time t2 in the above figure, the length of the two long sides is S total length, and the included angle is θ initial inflation + θ initial straightening. The final position of the cable can be determined according to the trigonometric function relationship, and then the sweep range of the cable can be determined.

[0054] 3. Calculate the minimum distance D between the aircraft outline and the parachute cables.

[0055] Based on the aircraft's attitude angle σ and its geometric characteristics, the position of the tail fin at different attitude angles can be determined, as shown above. Figure 11 The green triangle in the middle.

[0056] pass Figure 11By establishing a geometric simulation model (models of the two triangles) based on the geometric relationship between the blue and green triangles, the minimum distance between the aircraft's outer contour and the cables can be obtained. From the moment the parachute inflates to generate the tension force F_parachute, to the complete elimination of the aircraft's forward velocity V_aircraft, the minimum distance D between the parachute cables and the aircraft fuselage should have sufficient margin. For different aircraft models, the desired margin is defined as a safety threshold, and then the angle that makes the minimum distance greater than the safety threshold can be selected as the safe launch angle.

[0057] This invention adds an adjustable emergency parachute launch angle to the traditional fixed-wing aircraft emergency parachute system. It can launch the emergency parachute at a suitable angle relative to the fuselage based on the real-time attitude and speed of the aircraft in an emergency, thus solving the problem that traditional rocket and parachute systems with non-adjustable launch angles may interfere with the aircraft control surfaces after launch.

[0058] While the structure of the present invention has been described above with reference to preferred embodiments, those skilled in the art should recognize that the above examples are merely illustrative and should not be construed as limiting the invention. Therefore, modifications and variations can be made to the present invention, all of which will fall within the scope defined by the appended claims.

Claims

1. An aircraft emergency parachute system with adjustable launch angle, comprising a parachute pack, a rocket launcher, and a parachute compartment, wherein the parachute compartment is located on the top of the aircraft fuselage and configured to accommodate the rocket launcher and the parachute pack. Its features are, The aircraft emergency parachute system with adjustable launch angle also includes: A gimbal, mounted within the parachute compartment, includes a launch rail having at least two degrees of freedom. The rocket launcher is mounted on the gimbal via the launch rail, allowing the launch axis of the rocket launcher to change with the movement of the launch rail. A controller is located inside the parachute compartment and is electrically connected to the gimbal and the rocket launcher. The controller is configured to adjust the angle of the rocket launcher based on the real-time attitude information of the aircraft.

2. The aircraft emergency parachute system with adjustable launch angle according to claim 1, characterized in that, The parachute compartment includes a partition that divides the interior space into a first compartment for accommodating the rocket launcher and a second compartment for accommodating the parachute pack; the gimbal is vertically fixedly mounted on the partition.

3. The aircraft emergency parachute system with adjustable launch angle according to claim 2, characterized in that, The partition has a concave opening for the cable connecting the rocket launcher and the parachute to pass through.

4. The aircraft emergency parachute system with adjustable launch angle according to claim 1, characterized in that, The parachute compartment also includes a parachute compartment cover, which covers the top of the parachute compartment, and the parachute compartment cover has an opening for the cable connecting the parachute pack to the fuselage hoisting point to pass through.

5. The aircraft emergency parachute system with adjustable launch angle according to claim 1, characterized in that, The gimbal includes a gyroscope with two degrees of freedom, and the launch rail is fixed to the gyroscope.

6. The aircraft emergency parachute system with adjustable launch angle according to claim 1, characterized in that, The controller integrates a gimbal control unit, an ignition control unit, and a power module. The gimbal control unit is configured to control the movement of the gimbal's slide rail, and the ignition control unit is configured to control the ignition of the rocket launcher.

7. The aircraft emergency parachute system with adjustable launch angle according to claim 1, characterized in that, The controller has a communication interface configured to interact with the aircraft inertial navigation system and / or ground control station to receive the real-time attitude information and remote parachute deployment commands. The controller is configured to calculate the safe launch angle based on the real-time attitude information.

8. The aircraft emergency parachute system with adjustable launch angle according to claim 7, characterized in that, The communication interface is further configured to receive the real-time speed information of the aircraft, wherein the calculation of the safe launch angle is based on both the real-time attitude information and the real-time speed information.

9. A method for launching an emergency parachute based on aircraft attitude, comprising the following steps: Obtain the aircraft's real-time attitude information; Based on the real-time attitude information, a safe launch angle is calculated to prevent the emergency parachute cable launched by the rocket launcher from interfering with the aircraft tail. The control unit is configured to rotate a gimbal that supports the rocket launch device, and adjusts the launch axis of the rocket launch device to the safe launch angle. The gimbal includes a launch rail for supporting the rocket launch device, and the launch rail has at least two degrees of freedom. After the rocket launcher is adjusted to the correct position, the rocket launcher is ignited to launch the emergency parachute at the safe launch angle.

10. The method for launching an emergency parachute based on aircraft attitude according to claim 9, characterized in that, The steps for calculating the safe launch angle include: Based on parameters such as rocket ejection velocity, aircraft velocity, length of the rocket-parachute connection cable, and emergency parachute inflation characteristics, the minimum distance between the parachute system cables and the aircraft profile is calculated at different launch angles; and... The angle at which the minimum distance is greater than the safety threshold is selected as the safe launch angle.

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