A method and system for controlling the launch speed of an electromagnetic catapult aircraft.

Abstract

This application belongs to the field of electromagnetic catapult technology, and relates to a method and system for controlling the launch speed of an electromagnetic catapult. The method includes: acquiring the separation moment and velocity of the aircraft during its acceleration from the catapult platform to its detachment; establishing the aircraft's dynamic equations and obtaining the real-time velocity equations; acquiring the electromagnetic catapult parameters and aircraft parameters; constructing the velocity state equations of the electromagnetic catapult and obtaining the velocity observation vector; obtaining the velocity fusion equation based on the velocity observation vectors and the velocity state equations of the electromagnetic catapult; constructing a Kalman filter; using the velocity observation vectors as the filtering observations; estimating the velocity error of the electromagnetic catapult; and providing velocity feedback based on the estimation results. This method can meet the needs of various aircraft with different launch speeds.

Description

Technical Field

[0001] This application relates to the field of electromagnetic catapult technology, and in particular to a method and system for controlling the launch speed of an electromagnetic catapult. Background Technology

[0002] Electromagnetic catapult technology is an important application of electromagnetic launch technology in aircraft such as drones and fire extinguishing bombs, and represents a significant improvement over traditional catapult technology. Electromagnetic launch technology utilizes electromagnetic force (energy) to propel objects to high or ultra-high speeds. By converting electromagnetic energy into the instantaneous kinetic energy required to launch the payload, it can accelerate loads ranging from grams to tens of tons to high speeds over short distances. Among electromagnetic catapult technologies, orbital launch offers advantages such as large payload capacity and high reliability. Orbital launch electromagnetic catapult technology uses electromagnetic force to accelerate the armature mover of a linear motor on a track, ejecting the aircraft along with the mover off the track, thus achieving the purpose of launching the aircraft. Orbital launch electromagnetic launch technology has significant advantages in launching large-mass, low-to-medium speed objects. It can effectively launch aircraft ranging from a few kilograms to tens of tons, offering advantages such as high launch speed, short start-up time, short launch intervals, and repeatability. It can effectively solve problems such as sintering of the launch system during traditional launch processes.

[0003] Orbital-launched electromagnetic catapult systems need to launch different types of aircraft, such as drones and fire extinguishing projectiles, with varying payload weights and required launch speeds. Therefore, the launch speed must be adjusted based on mission requirements, aircraft type, and payload. Taking a certain type of unguided fire extinguishing projectile as an example, launching it at 145 m / s versus 150 m / s results in a positional deviation of over 70 meters. If wind interference is considered, this deviation would be even greater, far exceeding the accuracy requirements of this type of projectile. To achieve an accuracy of less than 10 meters, the launch speed deviation needs to be no greater than 0.5 m / s. Some aircraft require speed deviations controlled to be below 0.1 m / s, and there are even attitude limitations.

[0004] However, in existing technologies, due to the influence of load, environment, power supply, energy storage and other factors, the speed deviation at higher speeds may reach more than 10 meters per second. The speed control methods of electromagnetic catapult aircraft cannot meet the needs of different catapult speeds of various aircraft, and cannot be controlled in real time with low control accuracy. Summary of the Invention

[0005] Therefore, it is necessary to provide a method and system for controlling the launch speed of an electromagnetic catapult aircraft to address the above-mentioned technical problems. This method and system can meet the needs of different launch speeds for various types of aircraft and improve control accuracy.

[0006] Methods for controlling the launch speed of electromagnetic catapult aircraft include:

[0007] Both the electromagnetic catapult and the aircraft are connected to a communicator to form a catapult speed control system. The maximum longitudinal acceleration of the catapult speed control system is calculated. The performance parameters of the electromagnetic catapult and the aircraft are obtained, and it is determined whether the maximum longitudinal acceleration exceeds the equipment load of the aircraft.

[0008] If the maximum longitudinal acceleration exceeds the equipment load of the aircraft, the aircraft offline speed control mode is adopted; if the maximum longitudinal acceleration does not exceed the equipment load of the aircraft, the aircraft online speed control mode is adopted.

[0009] When the aircraft is in offline speed control mode, the launch speed is controlled and judged based on the speed and acceleration of the electromagnetic catapult. When the specified launch speed is reached, the aircraft is released. The separation moment and separation speed of the aircraft during the acceleration from the launch platform of the electromagnetic catapult to the point of separation are obtained. Force analysis is performed on the moving aircraft to establish the dynamic equation of the aircraft. Based on the separation moment, the separation speed, and the dynamic equation of the aircraft, the real-time velocity equation of the aircraft is obtained. The real-time motion parameters of the aircraft are obtained, and the real-time actual velocity of the aircraft is calculated based on the real-time velocity equation of the aircraft. The aircraft then enters flight mode.

[0010] When the aircraft is in online speed control mode, the electromagnetic catapult parameters and aircraft parameters are acquired. Based on the electromagnetic catapult parameters, the output speed equation of the electromagnetic catapult is constructed. Based on the aircraft parameters, the output speed equation of the aircraft is constructed. Based on the electromagnetic catapult parameters and the aircraft parameters, the speed state equation of the electromagnetic catapult is constructed. Based on the output speed equations of the electromagnetic catapult and the aircraft, a speed observation vector is obtained. Based on the speed observation vector and the speed state equation of the electromagnetic catapult, a speed fusion equation is obtained, and a Kalman filter is constructed. Using the speed observation vector as the filtering observation, the speed error of the electromagnetic catapult is estimated. Based on the estimation result, speed feedback control is performed and a judgment is made. When the specified catapult speed is reached, the aircraft is released, and the aircraft enters flight mode.

[0011] In one embodiment, force analysis of a moving aircraft and establishment of its dynamic equations include:

[0012]

[0013] in,

[0014]

[0015]

[0016]

[0017] In the formula, The resultant force acting on the aircraft. For thrust, For gravity, For aerodynamics, The control force is m, where m is the mass of the aircraft. It is the instantaneous acceleration vector. As resistance, For lift, This is a lateral force.

[0018] In one embodiment, the real-time velocity equation of the aircraft is obtained based on the separation time, the separation velocity, and the aircraft's dynamic equations, including:

[0019]

[0020] In the formula, For the real-time speed of the aircraft, V is the separation velocity. B t1 is the transformation matrix from the aircraft body coordinate system to the velocity coordinate system, t1 is the separation time, and t is time.

[0021] In one embodiment, obtaining the real-time motion parameters of the aircraft and calculating the real-time velocity of the aircraft based on its real-time velocity equation includes:

[0022]

[0023] In the formula, For the real-time speed of the aircraft, t2 represents the three-dimensional inertial measurement velocity, and t2 is the stable output time.

[0024] In one embodiment, constructing the output velocity equation of the electromagnetic catapult based on the electromagnetic catapult parameters includes:

[0025]

[0026] In the formula, V dx V is the velocity in the X-axis direction output by the speed sensor of the electromagnetic catapult. dy V is the velocity in the Y-axis direction output by the speed sensor of the electromagnetic catapult. dz V is the velocity in the Z-axis direction output by the speed sensor of the electromagnetic catapult. rx V represents the actual velocity along the X-axis. ry V represents the actual velocity along the Y-axis. rz δV represents the actual velocity along the Z-axis. dxδV represents the velocity error of the electromagnetic catapult's velocity sensor along the X-axis. dy δV represents the velocity error of the electromagnetic catapult's velocity sensor along the Y-axis. dz The velocity error of the speed sensor of the electromagnetic catapult along the Z-axis direction.

[0027] In one embodiment, constructing the aircraft's output velocity equation based on the aircraft parameters includes:

[0028]

[0029] In the formula, V fx V is the velocity in the X-axis direction output by the inertial navigation module of the aircraft. fy V is the velocity in the Y-axis direction output by the inertial navigation module of the aircraft. fz δV is the velocity in the Z-axis direction output by the inertial navigation module of the aircraft. fx δV represents the velocity error of the aircraft's inertial navigation module along the X-axis. fy δV represents the velocity error of the aircraft's inertial navigation module along the Y-axis. fz This represents the velocity error of the aircraft's inertial navigation module along the Z-axis.

[0030] In one embodiment, constructing the velocity state equation of the electromagnetic catapult aircraft based on the electromagnetic catapult parameters and the aircraft parameters includes:

[0031]

[0032] in,

[0033]

[0034]

[0035]

[0036] In the formula, X t (t) represents the state variable in the velocity state equation. To find the derivatives with respect to the state variables, F(t) is the system dynamic matrix of the state information error parameters, G(t) is the system noise distribution matrix, W(t) is the system noise vector, Δψ is the angle between the electromagnetic catapult's guide rail and the X-axis, Δθ is the angle between the electromagnetic catapult's guide rail and the Y-axis, Δγ is the angle between the electromagnetic catapult's guide rail and the Z-axis, and δV fx δV represents the velocity error of the aircraft's inertial navigation module along the X-axis. fy Let δV be the velocity error of the inertial navigation mode of the aircraft along the Y-axis. fzThe velocity error of the inertial navigation mode of the aircraft along the Z-axis. Let Δω be the attitude transformation matrix. dx Δω represents the angular acceleration error in the pitch direction of the electromagnetic catapult's launch platform when launching the aircraft. dy Δω represents the angular acceleration error in the tilting direction of the electromagnetic catapult's launch platform when it propels the aircraft. dz Δa represents the angular acceleration error in the roll direction of the electromagnetic catapult's launch platform when it propels the aircraft. dx Δa represents the axial acceleration error of the electromagnetic catapult's launch platform when it propels the aircraft. dy Let Δa be the longitudinal acceleration error of the electromagnetic catapult's catapult platform when it propels the aircraft. dz This refers to the lateral acceleration error of the electromagnetic catapult's launch platform when it propels the aircraft.

[0037] In one embodiment, the velocity observation vector is obtained based on the output velocity equations of the electromagnetic catapult and the aircraft, including:

[0038]

[0039] In the formula, Z V (t) is the velocity observation vector, δV ex δV represents the relative velocity error between the aircraft's inertial navigation module and the electromagnetic catapult's speed sensor along the X-axis. ey δV represents the relative velocity error in the Y-axis direction between the aircraft's inertial navigation module and the electromagnetic catapult's velocity sensor. ez H represents the relative velocity error between the aircraft's inertial navigation module and the electromagnetic catapult's speed sensor along the Z-axis. V (t) is the velocity measurement matrix, V V (t) is the velocity measurement noise vector.

[0040] The launch speed control system of the electromagnetic catapult adopts the launch speed control method of the electromagnetic catapult, including: electromagnetic catapult, aircraft and communicator;

[0041] The electromagnetic catapult includes: a power supply module, a motor control module, a catapult module, a speed control module, a monitoring module, and a catapult communication module; the power supply module, the motor control module, the catapult module, the speed control module, the monitoring module, and the catapult communication module are connected in sequence, and the motor control module is also connected to the speed control module and the monitoring module respectively;

[0042] The catapult communication module is connected to the aircraft via the communicator.

[0043] In one embodiment, the motor control module includes: an energy storage device, a pulse converter, a linear motor, and a motor closed-loop controller;

[0044] The energy storage device, the pulse converter, and the linear motor are connected in sequence and are all connected to the motor closed-loop controller. The energy storage device is connected to the power supply module, and the linear motor is connected to the launch module.

[0045] The aforementioned electromagnetic catapult launch speed control method and system are designed to control the launch speed of both the electromagnetic catapult and the aircraft. This allows for speed adjustment to meet the control needs of different types of aircraft with varying launch speeds. Considering the characteristics of catapult separation, a separation speed control stage is defined, enabling better planning of control implementation and improved controllability. After separation, the aircraft obtains its separation speed, which, after calculation, yields a real-time velocity. This real-time velocity facilitates high-precision and intelligent guidance control, resolving the issue of velocity calculation deviations after separation from the UAV at different launch speeds, and preventing aircraft malfunctions or flight failures due to inaccurate velocity calculations. An information transmission line for separation speed and separation time is designed between the electromagnetic catapult and the aircraft to prevent significant deviations in flight speed calculations when the aircraft is activated after separation. This makes aircraft control safer and avoids premature activation that could lead to malfunctions on the catapult platform, damaging the aircraft or the catapult system. During launch, onboard precision instruments can operate without powering on, preventing inaccurate measurements or damage to precision instruments caused by excessive catapult acceleration or strong electromagnetic interference. In speed control, a closed-loop speed control method was designed, which has strong adjustment capability and can greatly improve the control accuracy of the catapult speed, thus improving the launch accuracy of the aircraft and meeting the requirements of high-precision catapult speed control. In speed control, a speed fusion control method was designed, which correlates the speeds of the aircraft and the catapult, controlling the catapult speed in real time. This achieves the interaction and fusion of speed information. Specifically, the actual speed of the aircraft during catapult launch is fused into the speed control module of the electromagnetic catapult, enabling precise perception of the aircraft's speed. This helps the electromagnetic catapult ensure that the launch speed of the aircraft meets the set speed requirements, avoiding aircraft malfunctions or flight failures due to insufficient launch speed. Furthermore, data fusion between the aircraft speed and the electromagnetic catapult speed improves the system's reliability and speed control accuracy. During launch, the electromagnetic catapult and the aircraft achieve speed matching and coordination, with a small difference between the catapult's launch speed and the aircraft's actual speed, which is beneficial for the stable control of the aircraft after launch. Attached Figure Description

[0046] Figure 1 This is an application scenario diagram of the catapult speed control method for an electromagnetic catapult aircraft in one embodiment;

[0047] Figure 2 This is a flowchart illustrating the launch speed control method for an electromagnetic catapult aircraft in one embodiment;

[0048] Figure 3 This is a schematic diagram of the framework of the catapult speed control method for an electromagnetic catapult aircraft in one embodiment;

[0049] Figure 4 This is one of the schematic diagrams illustrating the force analysis of an aircraft in one embodiment;

[0050] Figure 5 This is the second schematic diagram of the force analysis of the aircraft in one embodiment;

[0051] Figure 6 This is a schematic diagram of the closed-loop speed control of the electromagnetic catapult and the aircraft in one embodiment.

[0052] Figure 7 This is a schematic diagram of the speed combination mode of the electromagnetic catapult and the aircraft in one embodiment;

[0053] Figure 8 This is a structural block diagram of the launch speed control system of an electromagnetic catapult aircraft in one embodiment;

[0054] Figure 9 This is a structural block diagram of an electromagnetic catapult in one embodiment;

[0055] Figure 10 This is a structural block diagram of an aircraft in one embodiment. Detailed Implementation

[0056] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application. All other embodiments obtained by those skilled in the art based on the embodiments in this application without inventive effort are within the scope of protection of this application.

[0057] It should be noted that all directional indicators (such as up, down, left, right, front, back, etc.) in the embodiments of this application are only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indicator will also change accordingly.

[0058] Furthermore, the use of terms such as "first" and "second" in this application is for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of those features. In the description of this application, "multiple sets" means at least two sets, such as two sets, three sets, etc., unless otherwise explicitly specified.

[0059] In this application, unless otherwise expressly specified and limited, the terms "connection," "fixed," etc., should be interpreted broadly. For example, "fixed" can mean a fixed connection, a detachable connection, or an integral part; it can mean a mechanical connection, an electrical connection, a physical connection, or a wireless communication connection; it can mean a direct connection or an indirect connection through an intermediate medium; it can mean the internal communication of two elements or the interaction between two elements, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0060] Furthermore, the technical solutions of the various embodiments of this application can be combined with each other, but only if they are based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such combination of technical solutions does not exist and is not within the scope of protection claimed by this application.

[0061] The method provided in this application can be applied to, for example... Figure 1 In the application environment shown, terminal 102 communicates with server 104 via a network. Terminal 102 may include, but is not limited to, various personal computers, laptops, smartphones, tablets, and portable wearable devices. Server 104 may be a server corresponding to various portal websites or work system backends.

[0062] This application provides a method for controlling the launch speed of an electromagnetic catapult aircraft, such as... Figure 2 and Figure 3 As shown, in one embodiment, the method is applied to Figure 1 Taking the terminal in the example, the explanation includes:

[0063] Step 202: Both the electromagnetic catapult and the aircraft are connected to the communicator to form a catapult speed control system. The maximum longitudinal acceleration of the catapult speed control system is calculated. The performance parameters of the electromagnetic catapult and the aircraft are obtained, and it is determined whether the maximum longitudinal acceleration exceeds the equipment load of the aircraft.

[0064] The calculation of the maximum longitudinal acceleration in this step is based on existing technology and will not be elaborated here; the equipment load of the aircraft is preset according to the performance parameters of the aircraft, and the specific preset values ​​may vary.

[0065] Step 204: If the maximum longitudinal acceleration exceeds the equipment load of the aircraft, the aircraft offline speed control mode is adopted; if the maximum longitudinal acceleration does not exceed the equipment load of the aircraft, the aircraft online speed control mode is adopted.

[0066] In this step, different control modes are used. In offline mode, the onboard precision instruments and equipment can operate without being powered on during launch, avoiding inaccurate measurements or damage to the precision instruments caused by excessive launch acceleration or strong electromagnetic interference. In online mode, speed control can be performed accurately in real time.

[0067] Step 206: When the aircraft is in offline speed control mode, the launch speed feedback control is performed based on the speed and acceleration of the electromagnetic catapult, and the aircraft is released when the specified launch speed is reached; the separation moment and separation speed of the aircraft during the acceleration process from the launch platform of the electromagnetic catapult to the separation process are obtained; the forces of the moving aircraft are analyzed, and the dynamic equation of the aircraft is established; based on the separation moment, separation speed, and the dynamic equation of the aircraft, the real-time velocity equation of the aircraft is obtained; the real-time motion parameters of the aircraft are obtained, and the real-time true speed of the aircraft is calculated based on the real-time velocity equation of the aircraft, and the aircraft enters flight mode.

[0068] Specifically:

[0069] In the offline speed control mode of the aircraft, the aircraft is not powered on, the inertial navigation module is not working, and the guidance module does not perform speed calculation. The communicator waits to receive the separation time and separation speed sent by the electromagnetic catapult communication device, generates speed control commands, and determines whether the specified catapult speed has been reached. It should be noted that the separation time and separation speed are the separation time and separation speed during the process of the aircraft accelerating from the catapult platform of the electromagnetic catapult to the separation speed.

[0070] like Figure 4 and Figure 5 As shown, force analysis is performed on the moving aircraft, and the dynamic equations of the aircraft are established:

[0071]

[0072] in,

[0073]

[0074]

[0075]

[0076] In the formula, The resultant force acting on the aircraft. For thrust, For gravity, For aerodynamics, The control force is m, where m is the mass of the aircraft. It is the instantaneous acceleration vector. As resistance, For lift, This is a lateral force.

[0077] It should be noted that during this stage, the control system on the aircraft is usually not working, and the thrust equipment such as the engine is also not working. Therefore, the thrust and control force can be considered to be zero. The drag, lift and lateral force can be obtained from the current speed, reference area and aerodynamic parameters of the aircraft. The reference area and aerodynamic parameters of the designed aircraft are known.

[0078] Based on the separation time, separation velocity, and the aircraft's dynamic equations, the real-time velocity equations of the aircraft are obtained. Specifically, since the inertial navigation module is not yet functioning properly at this time, the real-time velocity of the aircraft at any moment during this stage can be derived using the instantaneous acceleration vector, resulting in the aircraft's real-time velocity equations:

[0079]

[0080] In the formula, For the real-time speed of the aircraft, V is the separation velocity. B t1 is the transformation matrix from the aircraft body coordinate system to the velocity coordinate system, where t1 is the separation time and t is time.

[0081] Under normal circumstances, V B In a short time, it can be considered as a unit matrix, therefore:

[0082]

[0083] It should be noted that after the aircraft physically separates from the catapult platform, the guidance module activates the inertial navigation module and other precision instruments after receiving the separation moment. At the same time, it starts to calculate the real-time speed of the aircraft based on the received separation moment and separation speed. Since the communication delay over short distances is less than milliseconds, it is assumed that there is no communication delay, and the separation moment received by the guidance module is the actual moment of separation.

[0084] The system acquires the real-time motion parameters of the aircraft, and after the inertial navigation module can stably output the measured values ​​from the gyroscope and accelerometer, it calculates the real-time velocity of the aircraft based on the real-time velocity equation.

[0085] Specifically:

[0086]

[0087] In the formula, For the real-time speed of the aircraft, t2 represents the three-dimensional inertial measurement velocity, and t2 represents the stable output time (specifically, the stable output time of the inertial navigation module).

[0088] In this step, after receiving the separation moment, the aircraft's guidance module activates the inertial navigation module and outputs the aircraft's real-time motion parameters. Once powered on, the inertial navigation module continuously and stably outputs flight attitude, position, velocity, and acceleration information to the guidance module in real time. The inertial navigation module's three-dimensional inertial measurement velocity can be transmitted to the guidance module in real time for calculating the aircraft's real-time velocity (i.e., calculating and correcting flight control information). It should be noted that when the flight control system (i.e., the aircraft's control module) calculates and corrects flight control information, it receives timestamp information from the electromagnetic catapult; the timestamp information refers to the instantaneous velocity at launch with a timestamp.

[0089] Step 208: When the aircraft is in online speed control mode, acquire the electromagnetic catapult parameters and the aircraft parameters; construct the output speed equation of the electromagnetic catapult based on the electromagnetic catapult parameters; construct the output speed equation of the aircraft based on the aircraft parameters; construct the speed state equation of the electromagnetic catapult based on the electromagnetic catapult parameters and the aircraft parameters; obtain the speed observation vector based on the output speed equation of the electromagnetic catapult and the output speed equation of the aircraft; obtain the speed fusion equation based on the speed observation vector and the speed state equation of the electromagnetic catapult, and construct a Kalman filter. Use the speed observation vector as the filtering observation to estimate the speed error of the electromagnetic catapult, and perform speed feedback control and judgment based on the estimation results. When the specified catapult speed is reached, release the aircraft, and the aircraft enters flight mode.

[0090] Specifically:

[0091] The parameters of an electromagnetic catapult include: the actual speed of the electromagnetic catapult in the X, Y, and Z axes; the speed error of the electromagnetic catapult's speed sensor along the X, Y, and Z axes; the angle between the electromagnetic catapult's guide rail and the X, Y, and Z axes (mainly the sum of the aircraft's installation angle on the catapult platform and the installation error angle); the angular acceleration error of the electromagnetic catapult's catapult platform when launching the aircraft; and the acceleration error of the electromagnetic catapult's catapult platform when launching the aircraft.

[0092] The aircraft parameters include: the velocities output by the aircraft's inertial navigation module in the X, Y, and Z axes, and the velocity errors of the aircraft's inertial navigation module along the X, Y, and Z axes.

[0093] Based on the parameters of the electromagnetic catapult, construct the output velocity equation of the electromagnetic catapult's velocity sensor:

[0094]

[0095] In the formula, V dx V is the velocity in the X-axis direction output by the speed sensor of the electromagnetic catapult. dy V is the velocity in the Y-axis direction output by the speed sensor of the electromagnetic catapult. dz V is the velocity in the Z-axis direction output by the speed sensor of the electromagnetic catapult. rx V represents the actual velocity of the electromagnetic catapult along the X-axis. ry V represents the actual velocity of the electromagnetic catapult along the Y-axis. rz δV represents the actual velocity of the electromagnetic catapult along the Z-axis. dx δV represents the velocity error of the electromagnetic catapult's velocity sensor along the X-axis. dy δV represents the velocity error of the electromagnetic catapult's velocity sensor along the Y-axis. dz The velocity error of the speed sensor of the electromagnetic catapult along the Z-axis direction.

[0096] When the aircraft is moving on the catapult platform of the electromagnetic catapult, the inertial navigation module is in normal working condition and can output stable flight attitude, position, velocity, and acceleration information. During this period, based on the aircraft parameters, the output velocity equation of the aircraft's inertial navigation module is constructed:

[0097]

[0098] In the formula, V fx V is the velocity in the X-axis direction output by the inertial navigation module of the aircraft. fy V is the velocity in the Y-axis direction output by the inertial navigation module of the aircraft. fz δV is the velocity in the Z-axis direction output by the inertial navigation module of the aircraft. fx δV represents the velocity error of the aircraft's inertial navigation module along the X-axis. fy δV represents the velocity error of the aircraft's inertial navigation module along the Y-axis. fz This represents the velocity error of the aircraft's inertial navigation module along the Z-axis.

[0099] Based on the electromagnetic catapult parameters and the aircraft parameters, the velocity state equation of the electromagnetic catapult aircraft, i.e., the velocity state equation of the velocity control module, is constructed:

[0100]

[0101] In the formula, X t(t) represents the state variable in the velocity state equation. To find the derivative with respect to the state variables, F(t) is the system dynamic matrix of the state information error parameters, G(t) is the system noise distribution matrix, and W(t) is the system noise vector;

[0102] It should be noted that F(t) is a (6×6) square matrix, and the elements on its main diagonal are generally 0. The parameters of F(t) are related to the specific electromagnetic catapult and aircraft, and are usually small values. The parameters can be given by the system configuration or are parameters obtained from velocity fusion statistics. The state information error parameters are directly generated by the performance of the velocity control module, including 6 error quantities, namely the attitude error on the three axes and the velocity error on the three axes.

[0103] And:

[0104]

[0105] In the formula, Δψ is the angle between the guide rail of the electromagnetic catapult and the X-axis, Δθ is the angle between the guide rail of the electromagnetic catapult and the Y-axis, and Δγ is the angle between the guide rail of the electromagnetic catapult and the Z-axis.

[0106] System noise allocation matrix:

[0107]

[0108]

[0109] In the formula, This is the attitude transformation matrix;

[0110] System noise vector:

[0111]

[0112] In the formula, Δω dx Δω represents the angular acceleration error in the pitch direction of the electromagnetic catapult's launch platform when launching the aircraft. dy Δω represents the angular acceleration error in the tilting direction of the electromagnetic catapult's launch platform when it propels the aircraft. dz Δa represents the angular acceleration error in the roll direction of the electromagnetic catapult's launch platform when it propels the aircraft. dx Δa represents the axial acceleration error of the electromagnetic catapult's launch platform when it propels the aircraft. dy Let Δa be the longitudinal acceleration error of the electromagnetic catapult's catapult platform when it propels the aircraft. dz This refers to the lateral acceleration error of the electromagnetic catapult's launch platform when it propels the aircraft.

[0113] It should be noted that since the launch platform is in a suspended state during the launch process of the electromagnetic catapult, there are noise interferences such as angular acceleration wander and acceleration wander. Therefore, angular acceleration error and acceleration error need to be considered.

[0114] Based on the output velocity equations of the electromagnetic catapult and the aircraft, the velocity observation vector is obtained:

[0115]

[0116] Among them, in H V (t) When guide rail deformation is not considered:

[0117] H V (t)=[0 3×3 I 3*3 ]

[0118] In the formula, Z V (t) is the velocity observation vector, δV ex δV represents the relative velocity error between the aircraft's inertial navigation module and the electromagnetic catapult's speed sensor along the X-axis. ey δV represents the relative velocity error in the Y-axis direction between the aircraft's inertial navigation module and the electromagnetic catapult's velocity sensor. ez H represents the relative velocity error between the aircraft's inertial navigation module and the electromagnetic catapult's speed sensor along the Z-axis. V (t) is the velocity measurement matrix, V V (t) is the velocity measurement noise vector.

[0119] Based on the velocity observation vector and the velocity state equation of the electromagnetic catapult, the velocity fusion equation is obtained:

[0120]

[0121] In the formula, The velocity state equation for an electromagnetic catapult aircraft is Z. V (t) is the velocity observation vector.

[0122] A Kalman filter is constructed, using the velocity observation vector as the filtering observation, to estimate the velocity error of the electromagnetic catapult, and velocity feedback is provided based on the estimation result. In other words, according to the velocity fusion equation, information fusion algorithms based on Kalman filtering, extended Kalman filtering, and least squares can be implemented to fuse velocity information. The fused velocity information serves as control feedback information, which is transmitted through the velocity control module to the monitoring module and the motor closed-loop controller as the catapult speed control signal.

[0123] In this step, speed feedback control is performed and a judgment is made based on the estimation results. When the specified launch speed is reached, the aircraft is released. When the specified launch speed is not reached, the aircraft returns to acceleration. That is, the real-time information of the electromagnetic catapult and the aircraft is continuously acquired, speed fusion is performed, speed control commands are generated and judged, until the specified launch speed is reached and the aircraft is released.

[0124] In this embodiment, the orientation is based on the aircraft's inertial navigation module as the main subsystem and the electromagnetic catapult speed sensor as the auxiliary subsystem. The center of gravity of the aircraft is 0, the X-axis is the axis pointing towards the head, the Y-axis is located in the longitudinal symmetry plane of the aircraft and is perpendicular to the X-axis, and the Z-axis is determined according to the X-axis and Y-axis by the right-hand rule.

[0125] like Figure 3 As shown, the launch speed control method of the electromagnetic catapult adopts hierarchical control, and its specific steps are as follows:

[0126] a) After the electromagnetic catapult is powered on, first perform the initialization and system self-test of the electromagnetic catapult, and locate the corresponding mechanical zero position. Then, place the corresponding aircraft on the catapult platform of the electromagnetic catapult, fix it, and lock the corresponding latches.

[0127] b) Input the aircraft's weight, dimensions, and other parameters into the monitoring module, and input the launch speed into the monitoring module.

[0128] c) The monitoring module determines the corresponding motor control commands and speed control commands based on the aircraft parameters, loading speed, and electromagnetic catapult parameters, and calculates the maximum longitudinal acceleration.

[0129] d) The monitoring module determines whether the maximum longitudinal acceleration exceeds the aircraft's equipment load based on the maximum longitudinal acceleration and the aircraft's performance parameters. If it does not exceed the load, the aircraft adopts the online speed control mode; if it does exceed the load, the aircraft adopts the offline speed control mode.

[0130] e) Employing the online speed control mode, the aircraft is powered on, and the flight control system is operational. The electromagnetic catapult operates, and the linear motor, under the control of the motor control subsystem, drives the catapult platform. The aircraft's flight control system continuously senses position, velocity, acceleration, and attitude information, transmitting this information to the electromagnetic catapult's monitoring module via communication equipment. Simultaneously, the speed sensors on the electromagnetic catapult acquire the catapult platform's velocity and acceleration information and transmit this information to the monitoring module. The monitoring module fuses the two sets of velocity and acceleration information and transmits it to the catapult speed control system, generating corresponding speed control commands. The catapult speed control system generates corresponding speed control signals and determines whether the aircraft's speed has reached the designated catapult speed. If not, speed control continues; if it has, a release command is issued, releasing the locking device and launching the aircraft. The aircraft then detaches from the electromagnetic catapult and enters the free flight phase.

[0131] f) In the offline speed control mode, the aircraft is not powered on and the flight control system is not operational, as the catapult acceleration may damage onboard equipment. When the electromagnetic catapult is operational, the linear motor, under the control of the motor control subsystem, drives the catapult platform. The speed sensors on the electromagnetic catapult obtain the speed and acceleration information of the catapult platform and transmit this information to the monitoring module. The monitoring module generates corresponding speed control commands, and the catapult speed control system generates corresponding speed control signals and determines whether the aircraft speed has reached the designated catapult speed. If not, speed control continues; if it has, a release command is issued, releasing the locking device and launching the aircraft. The aircraft detaches from the electromagnetic catapult and enters the free flight phase. At this point, the aircraft is powered on, and the flight control system begins operation. The electromagnetic catapult sends the timestamped catapult speed to the aircraft's flight control system. The flight control system calculates and corrects the corresponding flight control information based on its own inertial navigation information and the received catapult speed information to achieve high-precision flight control. This avoids damage to onboard equipment during excessive impact and obtains relatively accurate flight control information.

[0132] g) After the aircraft is launched from the electromagnetic catapult, the electromagnetic catapult recovers its energy, returns to its initial state, prepares for the next launch, and determines whether another launch is needed. If so, the aircraft is then mounted on the electromagnetic catapult's launch platform and the corresponding parameters are set.

[0133] like Figure 6As shown, the attitude and velocity information of the aircraft and the electromagnetic catapult are acquired in real time, and a velocity fusion equation composed of velocity state variables and velocity observations is obtained. Based on the information fusion algorithm, velocity fusion is performed, and the fused velocity information is used as a velocity control signal and fed back to the electromagnetic catapult. This effectively improves the accuracy of velocity control, thereby meeting the requirements for high-precision catapult velocity control. The velocity combination mode is as follows: Figure 7 As shown.

[0134] The above-mentioned method for controlling the launch speed of an electromagnetic catapult involves transmitting the separation speed to the aircraft at the moment of launch. The aircraft then calculates the real-time speed based on the separation speed and inertial navigation information. This application designs an electromagnetic catapult and aircraft launch speed control system, which can adjust the launch speed to meet the control needs of different types of aircraft with different launch speeds. Considering the characteristics of catapult separation, a separation speed control stage is defined, enabling better planning of control implementation and improving controllability. After separation, the aircraft obtains its separation speed, which, after calculation, yields a real-time velocity. Obtaining this real-time velocity facilitates high-precision and intelligent guidance control, resolving the issue of velocity calculation deviations after separation from the UAV at different launch speeds, and avoiding aircraft malfunctions or flight failures due to inaccurate velocity calculations. An information transmission line for separation speed and separation time is designed between the electromagnetic catapult and the aircraft, preventing significant deviations in flight speed calculations when the aircraft is activated after separation. This makes aircraft control safer, avoiding premature activation that could lead to malfunctions on the catapult platform, damaging the aircraft or the catapult system. During catapult launch, onboard precision instruments can operate without powering on, avoiding inaccurate measurements or damage to precision instruments caused by excessive catapult acceleration or strong electromagnetic interference. The electromagnetic catapult and the aircraft work together for speed control. The speed observation vector, which is the difference between the output speed of the aircraft's inertial navigation module and the output speed of the electromagnetic catapult's speed sensor, is used as the filtering observation. The speed error of the electromagnetic catapult is estimated by using the Kalman filter algorithm. Speed ​​feedback control information is then used to correct the speed control module of the electromagnetic catapult. This is beneficial for the stable control of the aircraft after launch and enables high-precision speed control during aircraft launch. This application designs an electromagnetic catapult and a launch speed control system for the aircraft. The electromagnetic catapult can adjust its launch speed to meet the control needs of various aircraft with different launch speeds. A closed-loop speed control method is designed, offering strong adjustment capabilities and significantly improving the control accuracy of the launch speed, thus enhancing the aircraft's launch accuracy and meeting the requirements for high-precision launch speed control. A speed fusion control method is also designed, linking the speeds of the aircraft and the catapult for real-time speed control. This achieves the interaction and fusion of speed information. Specifically, the actual speed of the aircraft during launch is fused into the speed control module of the electromagnetic catapult, enabling precise perception of the aircraft's speed. This ensures the electromagnetic catapult maintains the launch speed meets the set requirements, preventing aircraft malfunctions or flight failures due to insufficient launch speed. Furthermore, data fusion between the aircraft's speed and the electromagnetic catapult's speed improves system reliability and speed control accuracy. During launch, the electromagnetic catapult and the aircraft achieve speed matching and coordination, with a small difference between the catapult's launch speed and the aircraft's actual speed, facilitating stable control of the aircraft after launch.

[0135] It should be understood that, although Figure 2 The steps in the flowchart are shown sequentially as indicated by the arrows, but these steps are not necessarily executed in the order indicated by the arrows. Unless otherwise specified herein, there is no strict order in which these steps are executed, and they can be performed in other orders. Figure 2 At least some of the steps in the process may include multiple sub-steps or multiple stages. These sub-steps or stages are not necessarily completed at the same time, but can be executed at different times. The execution order of these sub-steps or stages is not necessarily sequential, but can be executed in turn or alternately with other steps or at least some of the sub-steps or stages of other steps.

[0136] This application also provides a catapult speed control system for an electromagnetic catapult aircraft, such as... Figures 8 to 10 As shown, in one embodiment, the system includes an electromagnetic catapult, an aircraft, and a communicator, with both the electromagnetic catapult and the aircraft connected to the communicator. The aircraft's fuselage is mounted on the catapult platform of the electromagnetic catapult.

[0137] The electromagnetic catapult includes: a power supply module, a motor control module, a catapult module, a speed control module, a monitoring module, and a catapult communication module; the power supply module, motor control module, catapult module, speed control module, monitoring module, and catapult communication module are connected in sequence, the motor control module is also connected to the speed control module and the monitoring module respectively, and the catapult communication module is connected to a communicator.

[0138] Specifically:

[0139] (1) The power supply module includes: battery or inverter; that is, there are two power supply methods: battery power supply or grid power supply.

[0140] When using grid power, an inverter is needed to transmit the grid power to the motor control module.

[0141] (2) The motor control module includes: an energy storage device, a pulse converter, a linear motor and a motor closed-loop controller; the energy storage device, the pulse converter and the linear motor are connected in sequence and are all connected to the motor closed-loop controller. The energy storage device is connected to the power supply module and the linear motor is connected to the launch module.

[0142] The energy storage device serves as the energy source for the electromagnetic catapult, providing power to the linear motor. The pulse converter inverts the DC output from the energy storage device into AC power required by the linear motor, providing an energy path for it. The linear motor acts as the actuator of the electromagnetic catapult, providing the aircraft with acceleration thrust and supplying information from the catapult to the motor's closed-loop controller. The linear motor is an advanced linear induction motor, composed of a series of discrete, identical stator units, facilitating installation and production. Each stator unit is equipped with a thyristor switch. When the mover passes a stator unit, the thyristor switch closes, propelling the mover forward and reducing the inverter current. Upon reaching the designated speed, the speed control module sends a speed-maintaining command to the motor control module, and the thyristor switches on subsequent stators no longer close, preventing further acceleration of the mover. The motor closed-loop controller controls the linear motor by using its position signal and parameters such as voltage and current. Specifically, it outputs the electrical energy stored in the energy storage device, which is then converted into pulse converter and sent to the linear motor to drive its mover. The motor closed-loop controller can determine whether the energy in the energy storage device is sufficient for the required speed. If not, it allows the power supply system to continue charging. If the energy is sufficient, it generates control commands to control the pulse converter and the linear motor to prepare for launch. The motor control module can also feed back the status and parameters of the linear motor, pulse converter, and energy storage device to the monitoring module for decision-making and control.

[0143] The motor control module operates as follows: When the monitoring module issues a launch command, the motor control module activates, and the linear motor moves, converting stored electrical energy into kinetic energy to launch the aircraft. When the electromagnetic catapult is operational, the speed control module sends acceleration or deceleration signals to the motor control module based on the speed deviation signal. The motor control module then controls the linear motor's mover to propel the launch platform. Once the platform reaches a specified speed, it determines whether the aircraft's speed and attitude meet the launch conditions. If they do, a launch command is issued, launching the aircraft. If not, the linear motor's mover speed is continuously adjusted based on the speed deviation signal until the launch conditions are met. After the aircraft physically separates from the launch platform, the monitoring module sends an energy recovery command based on the received separation signal. Upon receiving this command, the motor control module enters energy recovery mode, recovering energy, decelerating the mover, and converting kinetic energy into electrical energy, which is stored in the energy storage device for the next launch.

[0144] (3) The ejection module is located on the ejection frame and connected to the linear motor mover. It includes: the motor mover, the ejection platform and the speed sensor. The motor mover is connected to the motor control module and the ejection platform respectively. The speed sensor is connected to the motor mover or the ejection platform. Specifically, the speed sensor can be placed on the ejection track of the ejection frame or on the motor mover.

[0145] During aircraft ejection, the ejection platform primarily handles the electrical control of the physical connection between the aircraft and the ejection rack, such as locking and unlocking. The ejection platform can also transmit the timestamp of the physical separation between the aircraft and the ejection device to the monitoring module. The velocity sensor measures the velocity of the ejection platform carrying the aircraft on the ejection rack to obtain real-time velocity information of the aircraft on the track. The velocity sensor can be an eddy current velocity sensor, a laser velocity sensor, or a high-precision inertial device or satellite / inertial device. Typically, the velocity measurement accuracy of eddy current and laser velocity sensors is lower than that of the aircraft's inertial navigation module, typically at the meter level, and they are difficult to use to obtain attitude information. Therefore, a high-precision inertial device or satellite / inertial device can be installed on the ejection platform as a velocity sensor. This inertial device can have higher accuracy than the aircraft's inertial navigation module. The velocity and attitude information output by this inertial device can be fused with the aircraft's velocity and attitude information. Using the fused velocity information as control feedback information, the ejection speed control accuracy can exceed 0.1 m / s through the speed control module. The motion information of the motor mover can be indirectly obtained using the speed sensor on the launch platform of the electromagnetic catapult.

[0146] (4) The speed control module obtains the real-time speed information of the aircraft from the speed sensor in real time according to the speed command given by the monitoring module, performs corresponding numerical processing, eliminates noise and interference, and obtains the real speed of the aircraft on the track. When the speed reaches the specified launch speed given by the monitoring module, it sends a speed holding command to the motor control module. The speed control module can also transmit the speed of the aircraft on the track to the monitoring module in real time and add the corresponding timestamp to these speeds.

[0147] (5) The monitoring module is connected to the motor control module, speed control module and catapult communication module respectively. It can realize various controls of the electromagnetic catapult aircraft according to the instructions of the superior control system or the complete set of control instructions issued by the operator through the human-machine interface, including catapult, specifying catapult speed, transmitting catapult speed to the aircraft, etc.

[0148] (6) The ejection communication module and the flight communication module communicate through a communicator. The separation speed and corresponding timestamp obtained by the monitoring module after comparing the timestamps are sent to the aircraft. The physical separation information of the aircraft and the ejection platform obtained by the monitoring module can also be sent to the aircraft.

[0149] The aircraft includes: an inertial navigation module (i.e., an inertial navigation module), a guidance module (i.e., a guidance and control module), a control module, and a flight communication module; the inertial navigation module, guidance module, and control module are connected in sequence, and the guidance module is connected to the communicator through the flight communication module.

[0150] Specifically:

[0151] (1) The inertial navigation module is equipped with a three-axis gyroscope and a three-axis accelerometer. When the inertial navigation module is powered on, the gyroscope can provide the three-dimensional real-time angular velocity of the aircraft during flight. After integration, the three-dimensional real-time angle of the aircraft during flight is obtained, i.e., the flight attitude. The accelerometer can provide the three-dimensional real-time acceleration of the aircraft during flight. After integration, the three-dimensional inertial measurement velocity of the aircraft during flight is obtained. After integration again, the three-dimensional real-time position is obtained. The inertial navigation module can obtain the attitude, position, velocity, and acceleration information of the aircraft in real time, and send this information to the electromagnetic catapult through the guidance module and the communicator. The velocity measurement accuracy of the inertial navigation module is higher than 0.2 m / s, and the attitude angular velocity measurement accuracy is higher than 0.01° / s. The inertial navigation module acquires the real-time motion parameters of the aircraft, and after the inertial navigation module can stably output the measured values ​​obtained by the gyroscope and accelerometer, it calculates the real-time true velocity of the aircraft according to the real-time velocity equation of the aircraft.

[0152] (2) The guidance module is used to control the generation of guidance and control signals during the flight of the aircraft, and can control the power-on of various parts of the aircraft's flight control system. The guidance module controls the inertial navigation module to start after it detaches from the catapult according to a preset time or conditions, obtains the physical separation signal received by the flight communication module, and controls the power-on of precision instruments, equipment, and modules such as the inertial navigation module to begin operation. After the inertial navigation module starts working, it can also acquire the flight attitude, position, velocity, and acceleration information output by the inertial navigation module, and calculate the real-time flight velocity based on the separation velocity received by the flight communication module. The guidance module guides the aircraft to a designated target point. During the flight of the aircraft, by receiving navigation information provided by the inertial navigation module and other components, as well as measured target point positions, it continuously calculates the deviation between the actual motion and the ideal motion of the aircraft, generates corresponding ballistic parameters or guidance parameters, and transmits these parameters to the control module as control commands.

[0153] (3) The control module is a set of control devices installed on the aircraft. According to the control command and the specified control law, it generates the corresponding control force, and by changing the angular position or angular motion of the aircraft, it eliminates the influence of the deviation and realizes the tracking of the control command of the aircraft and attitude stabilization.

[0154] (4) The flight communication module receives information such as separation time and separation speed transmitted from the electromagnetic catapult in real time and sends this information to the guidance module.

[0155] The communication device communicates with the electromagnetic catapult's communication unit (i.e., the catapult communication module) and the aircraft's communication unit (i.e., the flight communication module). Communication can be wired or wireless. When using a wired connection, the physical interface between the aircraft and the electromagnetic catapult communication unit is located between the aircraft and the catapult platform, connected by a detachable connector. After a separation command is given during launch, the components can physically separate. When using a wireless connection, the aircraft's communication unit is located on the aircraft, while the electromagnetic catapult's communication unit is installed in a location less susceptible to electromagnetic interference. Communication of speed, attitude, and other signals is conducted via a corresponding communication protocol.

[0156] The aforementioned electromagnetic catapult launch speed control system adopts a hierarchical control system structure, consisting of three closed-loop control loops: a motor control loop, a catapult loop, and an integrated electromagnetic catapult-aircraft speed control loop. A speed control module is designed within the electromagnetic catapult. Before launch, operators can set a predetermined launch speed on the monitoring module, enabling speed control of the electromagnetic catapult. Simultaneously, speed control commands can originate from the control system above the motor control commands, such as the monitoring module. The entire closed-loop system ensures that the motor movement conforms to the motor control commands, achieving linear motion and stable control of the linear motor, and ensuring that the launch platform's speed conforms to the set speed targets. Since the aircraft's shape and weight are not fixed during actual launch, speed control overcomes the complexity of calculating launch power or energy. Only speed comparison is needed; by combining speed and acceleration information, the acceleration or deceleration information of the launch platform is obtained, thereby controlling the energy output of the linear motor's pulse converter and achieving launch speed control. A communicator is installed between the electromagnetic catapult and the aircraft for real-time communication. The system transmits the aircraft's attitude and velocity information to the electromagnetic catapult in real time. The catapult's velocity control module fuses the velocity information from the velocity sensors and the information transmitted by the aircraft. The fused velocity information serves as the velocity control signal and is fed back to the electromagnetic catapult, effectively improving the accuracy of velocity control and meeting the requirements for high-precision catapult velocity control. Alternatively, it can use only the catapult's built-in velocity sensors for velocity control, transmitting the time and velocity of the physical separation of the aircraft from the catapult platform. Based on the received separation velocity, the aircraft can calculate the actual flight velocity even when the inertial navigation module is not activated before launch or after launch and after activation. This means high-precision catapult velocity control can be implemented even when the aircraft is offline and powered on. The catapult velocity information is then sent to the powered-on aircraft, enabling normal flight control and achieving high-precision velocity control during launch. Furthermore, there may be differences between the actual launch state of the catapult platform and the aircraft. By incorporating the aircraft's flight information, integrated electromagnetic catapult-aircraft velocity control can be achieved, further improving the accuracy of catapult velocity control.

[0157] Specific limitations regarding the launch speed control system of electromagnetic catapults can be found in the above description of the launch speed control method for electromagnetic catapults, and will not be repeated here. Each module in the aforementioned device can be implemented entirely or partially through software, hardware, or a combination thereof. These modules can be embedded in or independent of the processor in a computer device in hardware form, or stored in the memory of a computer device in software form, so that the processor can call and execute the corresponding operations of each module.

[0158] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0159] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of this patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. A method of controlling the launch speed of an electromagnetic launched aircraft, characterized by, The electromagnetic catapult and the aircraft are connected with the communicator to form a catapult speed control system, and the maximum longitudinal acceleration of the catapult speed control system is calculated. The performance parameters of the electromagnetic catapult and the performance parameters of the aircraft are obtained, and it is determined whether the maximum longitudinal acceleration exceeds the equipment load of the aircraft. If the maximum longitudinal acceleration exceeds the equipment load of the aircraft, the aircraft off-line speed control mode is adopted; if the maximum longitudinal acceleration does not exceed the equipment load of the aircraft, the aircraft on-line speed control mode is adopted. When the aircraft off-line speed control mode is adopted, the catapult speed feedback control is performed according to the speed and acceleration of the electromagnetic catapult, and when the specified catapult speed is reached, the aircraft is released. The separation time and the separation speed of the aircraft during the acceleration from the electromagnetic catapult aircraft launch platform to the separation process are obtained, the force analysis of the moving aircraft is performed, the dynamic equation of the aircraft is established, the real-time speed equation of the aircraft is obtained according to the separation time, the separation speed and the dynamic equation of the aircraft, the real-time motion parameters of the aircraft are obtained, and the real-time actual speed of the aircraft is calculated according to the real-time speed equation of the aircraft, and the aircraft enters the flight mode. When the aircraft on-line speed control mode is adopted, the electromagnetic catapult parameters and the aircraft parameters are obtained, the output speed equation of the electromagnetic catapult is constructed according to the electromagnetic catapult parameters, the output speed equation of the aircraft is constructed according to the aircraft parameters, the speed state equation of the electromagnetic catapult aircraft is constructed according to the electromagnetic catapult parameters and the aircraft parameters, the speed observation vector is obtained according to the output speed equation of the electromagnetic catapult and the output speed equation of the aircraft, the speed fusion equation is obtained according to the speed observation vector and the speed state equation of the electromagnetic catapult aircraft, and the Kalman filter is constructed, the speed observation vector is taken as the filter observation, the speed error of the electromagnetic catapult aircraft is estimated, the speed feedback control is performed according to the estimation result, and when the specified catapult speed is reached, the aircraft is released, and the aircraft enters the flight mode. The force analysis of the moving aircraft is performed, and the dynamic equation of the aircraft is established, including:

2. The electromagnetic aircraft launch vehicle launch speed control method of claim 1, wherein, The real-time speed equation of the aircraft is obtained according to the separation time, the separation speed and the dynamic equation of the aircraft, including: The real-time motion parameters of the aircraft are obtained, and the real-time actual speed of the aircraft is calculated according to the real-time speed equation of the aircraft, including: wherein is the resultant of the forces acting on the aircraft, is the thrust, is the gravitational force, is the aerodynamic force, is the control force, m is the mass of the aircraft, is the instantaneous acceleration vector, is the drag, is the lift, is the side force.

3. The electromagnetic aircraft launch vehicle launch velocity control method of claim 2, wherein, The output speed equation of the electromagnetic catapult is constructed according to the electromagnetic catapult parameters, including: wherein is the real-time speed of the aircraft, is the separation speed, V B is the transformation matrix from the aircraft body coordinate system to the speed coordinate system, t1 is the separation time, and t is the time.

4. The electromagnetic aircraft launch vehicle launch velocity control method of claim 3, wherein, The output speed equation of the aircraft is constructed according to the aircraft parameters, including: wherein is the real-time true speed of the aircraft, is the three-dimensional inertial measurement speed, and t2 is the time of stable output.

5. The electromagnetic aircraft launch acceleration velocity control method according to any one of claims 1 to 4, characterized by, The speed state equation of the electromagnetic catapult aircraft is constructed according to the electromagnetic catapult parameters and the aircraft parameters, including: wherein V dx is the velocity in the X-axis direction output from the velocity sensor of the electromagnetic catapult, V dy is the velocity in the Y-axis direction output from the velocity sensor of the electromagnetic catapult, V dz is the velocity in the Z-axis direction output from the velocity sensor of the electromagnetic catapult, V rx is the true velocity in the X-axis direction, V ry is the true velocity in the Y-axis direction, V rz is the true velocity in the Z-axis direction, δV dx is the velocity error in the X-axis direction of the velocity sensor of the electromagnetic catapult, δV dy is the velocity error in the Y-axis direction of the velocity sensor of the electromagnetic catapult, δV dz is the velocity error in the Z-axis direction of the velocity sensor of the electromagnetic catapult.

6. The electromagnetic aircraft launch vehicle launch speed control method of claim 5, wherein, The speed observation vector is obtained according to the output speed equation of the electromagnetic catapult and the output speed equation of the aircraft, including: where V fx is the velocity of the aircraft in the X-axis direction output by the inertial navigation module of the aircraft, V fy is the velocity of the aircraft in the Y-axis direction output by the inertial navigation module of the aircraft, V fz is the velocity of the aircraft in the Z-axis direction output by the inertial navigation module of the aircraft, δV fx is the velocity error of the aircraft in the X-axis direction output by the inertial navigation module of the aircraft, δV fy is the velocity error of the aircraft in the Y-axis direction output by the inertial navigation module of the aircraft, δV fz is the velocity error of the aircraft in the Z-axis direction output by the inertial navigation module of the aircraft.

7. The electromagnetic aircraft launch vehicle launch velocity control method of claim 6, wherein, The electromagnetic catapult aircraft catapult speed control method of any one of claims 1 to 8 is adopted, including an electromagnetic catapult, an aircraft and a communicator. ​ wherein X t (t) is a state variable of the velocity state equation, is the derivative of the state variable, F(t) is the system dynamic matrix of the state information error parameter, G(t) is the system noise distribution matrix, W(t) is the system noise vector, Δψ is the angle between the guide rail of the electromagnetic catapult and the X axis, Δθ is the angle between the guide rail of the electromagnetic catapult and the Y axis, Δγ is the angle between the guide rail of the electromagnetic catapult and the Z axis, δV fx is the velocity error of the inertial navigation module of the aircraft along the X axis, δV fy is the velocity error of the inertial navigation module of the aircraft along the Y axis, δV fz is the velocity error of the inertial navigation module of the aircraft along the Z axis, is the attitude transformation matrix, Δω dx is the angular acceleration error of the launch platform of the electromagnetic catapult in the pitch direction when driving the aircraft to launch, Δω dy is the angular acceleration error of the launch platform of the electromagnetic catapult in the roll direction when driving the aircraft to launch, Δω dz is the angular acceleration error of the launch platform of the electromagnetic catapult in the roll direction when driving the aircraft to launch, Δa dx is the acceleration error of the launch platform of the electromagnetic catapult in the axial direction when driving the aircraft to launch, Δa dy is the acceleration error of the launch platform of the electromagnetic catapult in the longitudinal direction when driving the aircraft to launch, Δa dz is the acceleration error of the launch platform of the electromagnetic catapult in the lateral direction when driving the aircraft to launch.

8. The electromagnetic aircraft launch vehicle launch velocity control method of claim 7, wherein, ​ where Z V (t) is the velocity observation vector, δV ex is the relative velocity error between the inertial navigation module of the aircraft and the velocity sensor of the electromagnetic catapult in the X axis direction, δV ey is the relative velocity error between the inertial navigation module of the aircraft and the velocity sensor of the electromagnetic catapult in the Y axis direction, δV ez is the relative velocity error between the inertial navigation module of the aircraft and the velocity sensor of the electromagnetic catapult in the Z axis direction, H V (t) is the velocity measurement matrix, V V (t) is the velocity measurement noise vector.

9. A system for controlling the launch speed of an electromagnetic aircraft launcher, characterized in that, ​ The electromagnetic catapult comprises a power supply module, a motor control module, a catapult module, a speed control module, a monitoring module and a catapult communication module; the power supply module, the motor control module, the catapult module, the speed control module, the monitoring module and the catapult communication module are sequentially connected; the motor control module is further connected with the speed control module and the monitoring module respectively; The catapult communication module is connected with the aircraft through the communication device.

10. The electromagnetic aircraft launch acceleration velocity control system of claim 9, wherein, The motor control module comprises an energy storage device, a pulse converter, a linear motor and a motor closed-loop controller; The energy storage device, the pulse converter and the linear motor are sequentially connected and are all connected with the motor closed-loop controller; the energy storage device is connected with the power supply module; the linear motor is connected with the catapult module.

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