阅读说明：本技术 一种基于满足载荷投放点多约束条件下的分离窗口设计方法 (Separation window design method based on condition of satisfying multiple constraints of load release points ) 是由 孙胜 孙永丰 卞李坤 谢雪明 田佳彪 于晗 于 2021-07-08 设计创作，主要内容包括：一种基于满足载荷投放点多约束条件下的分离窗口设计方法,是一种多约束条件下投放的运载平台制导控制方法。该方法针对商业火箭运载器分离窗口需要同时满足飞行高度、马赫数、动压和姿态角的范围要求,把约束条件分解成先达到的边界指标、后达到的边界指标和可优化的边界指标,并把这些指标作为相应的转段条件从而把载荷投放飞行段分解为载荷投放飞行前段、载荷准备投放段、载荷马上投放段,使得载荷投放时性能指标最优化,同时在载荷飞行段对俯仰程序角和偏航程序角指令进行补偿,使得飞行攻角和侧滑角尽量接近于零,达到更好的载荷平台投放效果。(A design method of a separation window based on the condition of meeting multiple constraints of load release points is a guidance control method of a carrying platform released under the multiple constraints. The method aims at the requirement that a separation window of a commercial rocket carrier simultaneously meets the range requirements of flight height, Mach number, dynamic pressure and attitude angle, the constraint condition is decomposed into boundary indexes which are reached first, boundary indexes which are reached later and boundary indexes which can be optimized, the indexes are used as corresponding turning conditions, so that a load throwing flight section is decomposed into a load throwing flight front section, a load preparation throwing section and a load immediate throwing section, the performance indexes are optimized during load throwing, and meanwhile, pitching program angle and yawing program angle instructions are compensated in the load throwing section, so that the flight attack angle and sideslip angle are close to zero as much as possible, and a better load platform throwing effect is achieved.)

1. A design method for a separation window based on the condition of meeting multiple constraints of load releasing points is characterized in that in the whole load releasing flight section, in order to reduce an attack angle and a sideslip angle in the flight process as much as possible and enable the load releasing condition to be more optimized, the corresponding flight pitching program angle and the corresponding yaw program angle are obtained through the following formulas:

ψ_cx＝σ_vg-Δψ

wherein, theta_vgAnd σ_vgRespectively a downward velocity inclination angle and a velocity deflection angle of the emitting system,and Δ ψ is the pitch program angle requiring compensationBias and yaw program angle bias.

2. The load drop flight segment guidance algorithm of claim 1, wherein: the four conditions that need to be satisfied according to the load release are shown as follows:

h＞h_min

q_min＜q＜q_max

Ma_min＜Ma＜Ma_max

the load launching flight section is divided into a load launching flight front section, a load launching preparation section and a load launching immediate launching section, and the constraint condition is decomposed into a boundary index which is reached first, a boundary index which is reached later and an optimizable boundary index which are used as corresponding transition conditions, so that the performance index of the load release separation window is optimized.

3. The design method of the separation window based on the condition of satisfying multiple constraints of load putting points according to the claims 1 and 2, characterized in that: in the front section of load throwing flight, if the flight state of the spacecraft meets the following conditions at the same time:

h＞h_min

q＜q_max

Ma＜Ma_max

the flying state is switched from the front stage of load throwing flying to the preparation stage of load throwing.

4. The design method of the separation window based on the condition of satisfying multiple constraints of load putting points according to the claims 1 and 2, characterized in that: in the load release preparation section, if the flight state of the spacecraft meets the following conditions at the same time:

h＞h_min

q＞q_min

Ma＞Ma_min

the flight state is switched from a load throwing preparation section to a load immediate throwing section; at the moment and judging the pitch attitude angle if the pitch attitude angle is satisfiedSetting a release transition judgment mark as 0; otherwise, setting a releasing and level-shifting judgment flag to be 1.

5. The design method of the separation window based on the condition of satisfying multiple constraints of load putting points according to the claims 1 and 2, characterized in that: entering a load immediate release section, and if the grade transition judgment mark is 0, passing T_gd(s) after load release; if the grade transition judgment flag is 1, judging the following conditions, if any one of the conditions is met, immediately releasing the load:

h＜h_min+Δh

q＞q_max-Δq

Ma＞Ma_max-ΔMa

wherein, T_gdAnd (4) releasing transition time for the load, and performing optimized selection on parameters according to the actual task condition. And the delta h, the delta q and the delta Ma are optimized controllable boundary ranges which are all numbers larger than zero, and are optimized and selected according to actual task conditions.

Technical Field

The invention discloses a separation window design method based on the condition of meeting multiple constraints of load releasing points, which is used for guidance design of an aerospace carrying platform under the condition of meeting multiple constraints of height, speed, dynamic pressure, angle and the like in a certain range when load releasing is needed, and belongs to the field of aircraft guidance control.

Background

The design of the separation window of the commercial carrier rocket is the last step of realizing the task of the commercial carrier rocket, and the separation window is used for conveying the load to a position meeting multiple constraint conditions for release so as to obtain the maximum test effect. The launching platform of a certain commercial rocket carrier requires that the launching height of the load is more than 35.5km, the flight Mach number is within the range of 1.8-2.5, the dynamic pressure is within the range of 1320-1620pa, and the pitching attitude angle is within the range of-20-0 degrees. In order to effectively meet the condition requirement of a separation window, an energy management maneuvering flight section is carried out after the power flight section of the commercial rocket is finished, the guidance residual error of the power flight section is effectively eliminated, a carrier shell is thrown off after the energy management maneuvering flight is finished, namely, the first-stage separation and the second-stage separation are carried out, and the carrier shell enters a load throwing section after the separation. Although the separation window has no direct index requirement, the flight altitude, the flight Mach number, the dynamic pressure and the pitching attitude angle are all within a certain range when the load launching separation moment is required to be met, and the flight attack angle and the sideslip angle are expected to be as small as possible at the load launching moment, so that the method belongs to the separation window design under the multi-constraint condition.

Because no guidance control technology designed for a separation window under a multi-constraint launching condition exists at present, a guidance control design method for carrying out target control according to a traditional design virtual point cannot meet the requirement of the separation window. In order to make the attack angle and sideslip angle as small as possible at the separation moment, the method provided by the invention provides a method for solving the effective compensation of the flight pitching program angle and the yawing program angle. In the process of flying in the load launching section, in order to simultaneously meet the requirements that the flying height, the flying Mach number, the dynamic pressure and the attitude angle of a load launching platform need to be in a certain area range, the load launching flying section is divided into a load launching flying front section, a load launching preparation section and a load launching immediate section, and the sections are switched according to the conditions which are firstly achieved and then achieved and the constraint conditions of optimized indexes in the actual flying process, so that the load launching separation of the carrying platform has more optimized conditions and better performance, and the engineering problem of load launching requirements under the condition of multiple constraints is effectively solved.

Disclosure of Invention

The technical problem to be solved by the invention is as follows: the method overcomes the defects of the prior art, in the flight process of a load throwing section, in order to meet the requirement that the flight height, the flight Mach number, the dynamic pressure and the attitude angle of a load throwing platform are required to be within a certain region range, the load throwing flight section is divided into a load throwing flight front section, a load throwing preparation section and a load throwing immediate throwing section, and the sections are switched according to the conditions which are achieved firstly, the conditions which are achieved secondly and the constraint conditions of optimized indexes in the actual flight process, so that the load throwing separation of the carrying platform has more optimized conditions. In the design of the guidance algorithm of the load launching section, a flight pitching program angle and a yawing program angle are provided for effective compensation, so that the attack angle and sideslip angle at the separation moment are as small as possible, and the load launching platform has better performance.

Compared with the prior art, the invention has the beneficial effects that:

(1) the guidance algorithm of the invention takes an actual engineering target as a requirement, and provides a method for effectively compensating a flight pitching program angle and a yawing program angle by a theoretical means, so that an attack angle sideslip angle at a separation moment is as small as possible.

(2) The method and the device aim at multiple constraint conditions required to be met at the load launching moment, and carry out segmentation according to the conditions achieved firstly and then and the constraint conditions of the optimization indexes in the actual flight process, so that the load launching separation moment of the carrying platform under all interference deviations not only meets the condition constraint requirements, but also has more optimized performance.

Drawings

Fig. 1 is a flowchart of a method for designing a split window based on satisfying multiple constraints of load drop points according to an embodiment of the present invention.

Detailed Description

A design method of a separation window based on the condition of meeting multiple constraints of load releasing points is characterized in that a load releasing section obtains corresponding pitching and yawing attitude angle instructions through theoretical derivation, and multiple constraint indexes are decomposed according to the actual flight process and serve as segment conversion conditions of corresponding subdivided segments.

The main process is as follows:

1) in the whole load throwing flight section, the corresponding flight pitch program angle and yaw program angle are obtained through the following formulas:

ψ_cx＝σ_vg-Δψ

wherein, theta_vgAnd σ_vgRespectively, the formula for the downward velocity inclination angle and the velocity deflection angle of the emission system is as follows:

wherein, V_x、V_y、V_zThe emission is the down velocity.And Δ ψ is a pitch program angular deviation and a yaw program angular deviation to be compensated, and the following formula is found:

wherein the content of the first and second substances,for the current projectile pitch attitude angle,is the current transmit-inertial frame to transmit frame transformation matrix.

2) The four conditions that need to be satisfied in load release are respectively:

h＞h_min

q_min＜q＜q_max

Ma_min＜Ma＜Ma_max

according to four conditions required to be met by load throwing, a load throwing flight section is divided into a load throwing flight front section, a load throwing preparation section and a load throwing immediate throwing section, and the turning sections are carried out under the condition that corresponding constraint conditions are met, wherein the turning section conditions are respectively as follows.

3) In the front section of the load launching flight, if the carrying platform simultaneously meets the following conditions, the carrying platform enters a load launching preparation section, and the conditions are shown as the following formula:

h＞h_min

q＜q_max

Ma＜Ma_max

4) when entering the load throwing preparation section, if the carrying platform simultaneously meets the following conditions, entering the load immediate throwing section, wherein the conditions are shown as the following formula:

h＞h_min

q＞q_min

Ma＞Ma_min

judging the pitch attitude angle at the moment of entering the immediate release section, if soSetting a release transition judgment mark as 0; otherwise, setting a releasing and level-shifting judgment flag to be 1.

5) Entering a load immediate release section, and if the grade transition judgment mark is 0, passing T_gd(s) after load release; if the grade transition judgment flag is 1, judging the following conditions, if any one of the conditions is met, immediately releasing the load:

h＜h_min+Δh

q＞q_max-Δq

Ma＞Ma_max-ΔMa

wherein, T_gdIn order to design parameters, optimization selection is carried out according to the actual task condition, and generally, the selection is dozens of milliseconds to hundreds of milliseconds. And the delta h, the delta q and the delta Ma are allowable controllable boundary ranges which are all numbers larger than zero, and are optimally selected according to the actual task condition.

Therefore, the method for designing the separation window based on the condition that the load throwing points and the multiple constraints are met is realized, the attack angle and the sideslip angle at the moment of load throwing are close to zero, the flight height, the Mach number, the dynamic pressure and the attitude angle which need to be met by the separation window at the same time are all in an expected range, and the performance index can be optimized greatly.