CN103592946A - Active section self-adaptive longitudinal guidance method based on view acceleration measurement - Google Patents

Abstract

A program-adaptive longitudinal guidance method in the active segment based on apparent acceleration measurement, accumulating and automatically adapting to the standard program angle according to the axial apparent velocity increments, to ensure that the program trajectory can still be flown with high accuracy under large dynamic deviations . Axial apparent speed incremental accumulation and -pitch program angle data table are bound in the form of various elements. The vehicle can generate program instructions only by relying on the apparent acceleration measurement, without other input conditions and complicated calculations; the guidance instructions are automatically generated according to the actual power level. Adapt to changes without auxiliary guidance, thus avoiding the contradiction of guidance amount distribution. In actual use, reliability measures are taken for the input and output quantities to ensure that the engineering application of the invention is feasible.

Description

A Method of Active Segment Program Adaptive Longitudinal Guidance Based on Apparent Acceleration Measurement

technical field

The invention relates to a guidance method, in particular to an adaptive longitudinal guidance method for active segment procedure flight.

Background technique

The characteristics of the flight of the carrier are to take off vertically, and then turn and fly according to the pre-calculated flight program. The guidance command is usually given in the form of a sequence of pitch program angles that vary with time. For ease of use, the guidance parameters are time-dependent variables The pitch program angle interpolation table or the pitch program angle polynomial fitting coefficient table with time as the independent variable. Arrow flight software performs linear interpolation calculation or polynomial calculation based on flight timing, and can issue guidance program instructions in real time. This method does not rely on measuring equipment, and the calculation is simple and reliable. If the flight conditions such as atmospheric state, engine characteristics, rocket body structure, etc. are all in line with the ideal situation, the vehicle will fly completely according to the theoretically calculated trajectory under the action of the program control signal. But in fact, there are many disturbing factors that make the flight conditions significantly deviate from the ideal situation, such as the second consumption deviation of the engine, the specific impulse deviation, the take-off mass deviation, the thrust deviation and lateral drift, and the wind. Even if the vehicle flies strictly according to the predetermined procedure, the above disturbance factors will interfere with the force and moment acting on the vehicle, causing its flight to deviate from the predetermined trajectory. In order to make the vehicle deviate from the predetermined trajectory in the vertical plane within the allowable range, normal guidance is also required. In order to ensure attitude stability and attitude tracking accuracy in flight, guidance must be restricted.

When there are serious disturbances, especially large dynamic deviations, the design of the guidance system faces the following contradictions: on the one hand, in order to ensure the tracking accuracy of the flight trajectory in the vertical plane, it is necessary to enhance the guidance; For stable flight of the flight path, it is necessary to limit the amount of guidance.

Contents of the invention

The technical problem solved by the present invention is: to overcome the deficiencies of the prior art, to provide a program-adaptive longitudinal guidance method for the active section based on apparent acceleration measurement, and to solve the problem of flying according to the predetermined trajectory when the dynamic deviation of the active section is large The problem of interference is stronger, and longitudinal guidance can be achieved without guidance assistance.

The technical solution of the present invention is: an active section program adaptive longitudinal guidance method based on apparent acceleration measurement, characterized in that the steps are as follows:

1) Generate a standard program sequence based on the theoretical parameters of apparent acceleration;

11) Select the axial direction of the vehicle as the axis of apparent acceleration measurement;

12) Substitute the preset time-pitch program angle sequence into the dynamic model of the vehicle to obtain the nominal trajectory of the vehicle; according to the nominal trajectory, obtain the cumulative sum of the axial apparent velocity increments and the pitch program angle of the active section of the vehicle ;

13) Make a graph of the accumulated axial apparent speed increment and - pitch program angle, select the table interval according to the control accuracy threshold, and establish the accumulated axial apparent speed increment and - pitch program angle table as a standard program sequence;

14) In the launch preparation stage of the vehicle, the axial apparent velocity incremental accumulation and -pitch program angle table are bound in the form of various elements;

2) According to the measured apparent acceleration measurement, adaptive guidance is performed based on the standard program sequence;

21) After judging the rationality of the apparent acceleration measurement and eliminating the outliers, the cumulative sum of the axial apparent velocity increments is obtained;

22) During the flight of the vehicle, use the cumulative sum of axial apparent velocity increments obtained in step 21) to perform linear interpolation on the cumulative sum of axial apparent velocity increments - pitch program angle data table to obtain the pitch program angle;

23) Judge the rationality of the pitch program angle obtained in step 22) according to the preset program angle change rate amplitude, and use the judged pitch program angle command to control the vehicle to fly according to the predetermined trajectory.

In step 13), segment fitting parameters can also be selected according to the control accuracy threshold, and a fitting parameter table can be established.

Step 21) The rationality of the apparent acceleration measurement is judged, and the specific method for obtaining the cumulative sum of axial apparent velocity increments after eliminating outliers is as follows:

211) Discriminate the rationality of the axial apparent velocity increment ΔW _x1 , and obtain the judged axial apparent velocity increment

为合理性判别后的轴向视速度增量，为前一周期视速度增量为主动段采样周期内最大视速度增量取值；In the formula

is the axial apparent velocity increment after rationality judgment, is the apparent speed increment of the previous cycle is the value of the maximum apparent velocity increment within the sampling period of the active segment;

获取轴向视速度增量和

其中累计零点为发动机点火时刻。212) According to the judged axial apparent velocity increment obtained in step 211)

Get the axial apparent velocity delta and

The accumulative zero point is the ignition time of the engine.

The specific method for judging the rationality of the pitch program angle obtained in step 22) in step 23) is as follows:

231) Obtain the limit value of pitch program angle increment

分别为各段俯仰程序角增量限幅值；In the formula, W1 and W2 are respectively the cumulative sum of apparent velocity increments corresponding to the angular velocity limit conversion point of the pitch program;

Respectively, the pitch program angle increment limit value of each segment;

对俯仰程序角进行合理性判别:232) Use pitch program angle increment limit value

Pitch program angle Make a reasonable judgment:

为前一周期俯仰程序角指令，

为基于视加速度测量的主动段程序自适应纵向制导技术得到的程序指令，即判别后的俯仰程序角指令。In the formula

is the pitch program angle command in the previous cycle,

It is the program command obtained by the active segment program adaptive longitudinal guidance technology based on apparent acceleration measurement, that is, the pitch program angle command after discrimination.

The advantage of the present invention compared with prior art is:

(1) The guidance command changes adaptively according to the actual power level, without auxiliary guidance, thus avoiding the contradiction between guidance enhancement and guidance constraints.

(2) The adaptability to interference is enhanced, and the application range of the program angle is expanded, so as to ensure that it can still fly according to the program trajectory with high accuracy under large dynamic deviation.

(3) The implementation is simple, the axial apparent velocity incremental accumulation and the -pitch program angle data table are bound in the form of elements, and the vehicle can generate program instructions only by relying on the apparent acceleration measurement, without other input conditions and complex calculations.

(4) In actual use, only the accelerometer in the inertial measurement device is relied on, and the inertial measurement technology is mature and reliable; reliability measures are taken for the input and output to ensure that the engineering application of this invention is feasible.

Description of drawings

Figure 1 shows the sequence steps of standard program generation based on theoretical parameters of apparent acceleration.

Figure 2 shows the implementation steps of adaptive guidance based on the standard program sequence based on the apparent acceleration measurement.

Fig. 3 is a graph corresponding to the time-pitch program angle sequence of a single-stage engine carrier.

Fig. 4 is a time-axial apparent velocity incremental sum curve corresponding to Fig. 3 .

Fig. 5 is the axial apparent speed incremental sum-pitch program angle curve corresponding to Fig. 3 .

Detailed ways

The present invention will be described in further detail below in conjunction with the accompanying drawings.

Take a single-stage engine carrier as an example:

1) Generate a standard program sequence based on the theoretical parameters of apparent acceleration:

11) According to the power configuration of the vehicle and the installation method of the inertial measurement sensitive components, the axial direction of the vehicle is selected as the apparent acceleration measurement axis. In the active section, the axial upward thrust of the vehicle plays a major role, so the cumulative sum of the axial apparent velocity increments of the active section of the vehicle also shows a monotonous increasing trend, which can be used as the independent variable of the program angle interpolation, that is, the cumulative sum of the apparent velocity increments and identify unique program angles.

12) As shown in Figure 3, taking a single-stage engine carrier as an example, the curve corresponding to its time-pitch program angle sequence is shown in the figure. The abscissa T represents time, and the ordinate FICX represents the pitch program angle; it can be seen from Figure 3 that the vehicle makes a rapid turn after take-off, and after maintaining a fixed-axis flight for a period of time, the program angle decreases slowly;

画出轴向视速度增量累加和-俯仰程序角曲线如图5，记录W_k、序列。According to the pre-designed time-pitch program angle, it is substituted into the dynamic model of the vehicle for simulation, and the nominal trajectory of the vehicle is obtained, and the axial apparent velocity incremental sum W _k and the pitch program angle of the active section of the vehicle are further obtained

Draw the axial apparent speed incremental accumulation and -pitch program angle curve as shown in Figure 5, record W _k , sequence.

序列，可采用分段细化刻度生成

数据表，作为标准程序序列，也可根据W_k对进行分段多项式拟合，生成拟合参数表。这里以前者为例进行详细说明。观察图5曲线变化规律，在W1、W2处程序角变化率变化显著，可取分段数为3。根据控制精度规划各段插值刻度。图5中，在视速度增量累加和小于W1时，曲线非线性明显，应细化插值刻度，最终建立数据表

13) For W _k obtained in step 12),

sequence, which can be generated using a piecewise refinement scale

data sheet, as a standard program sequence, is also available according to W _k for Perform piecewise polynomial fitting and generate a fitting parameter table. Here we take the former as an example to describe in detail. Observing the change law of the curve in Figure 5, the program angle change rate changes significantly at W1 and W2, and the number of segments is 3. Plan the interpolation scale of each segment according to the control accuracy. In Fig. 5, when the cumulative sum of apparent velocity increments is less than W1, the curve is obviously non-linear, and the interpolation scale should be refined to finally establish a data table

14) In the launch preparation stage of the vehicle, the designed axial apparent velocity incremental accumulation and -pitch program angle number tables are bound in the form of various elements.

2) According to the measured apparent acceleration measurement, adaptive guidance is performed based on the standard program sequence;

其合理性判别方法如下：21) After the aircraft starts to control, it starts to judge the rationality of the apparent speed increment ΔW _x1 , eliminates outliers, and calculates the axial apparent speed increment after the rationality judgment

The method of judging its rationality is as follows:

$\mathrm{<span\; class="notranslate">\; \&Delta;</span>}{\stackrel{<span\; class="notranslate">\; \&OverBar;</span>}{\mathrm{<span\; class="notranslate">\; W</span>}}}_{\mathrm{<span\; class="notranslate">\; x</span>}\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; =</span>\left\{\begin{array}{c}\mathrm{<span\; class="notranslate">\; \&Delta;</span>}{\mathrm{<span\; class="notranslate">\; W</span>}}_{\mathrm{<span\; class="notranslate">\; x</span>}\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; 0</span>}<span\; class="notranslate">\; <</span>\mathrm{<span\; class="notranslate">\; \&Delta;</span>}{\mathrm{<span\; class="notranslate">\; W</span>}}_{\mathrm{<span\; class="notranslate">\; x</span>}\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; <</span>\mathrm{<span\; class="notranslate">\; \&Delta;</span>}{\stackrel{<span\; class="notranslate">\; \&OverBar;</span>}{\mathrm{<span\; class="notranslate">\; W</span>}}}_{\mathrm{<span\; class="notranslate">\; MAX</span>}}\\ \mathrm{<span\; class="notranslate">\; \&Delta;</span>}{\stackrel{<span\; class="notranslate">\; \&OverBar;</span>}{\mathrm{<span\; class="notranslate">\; W</span>}}}_{\mathrm{<span\; class="notranslate">\; x</span>}\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; \_</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; else</span>}\end{array}\right.-<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; )</span>$

取当前采样周期的轴向视速度增量；否则取前一周期视速度增量

其中

为主动段采样周期内最大视速度增量取值，避免加表输出的野值问题。轴向视速度增量和W_Nx1累计零点为发动机点火时刻。计算方法为：That is, the condition of rationality is satisfied after control

Take the axial apparent velocity increment of the current sampling period; otherwise, take the apparent velocity increment of the previous period

in

The value of the maximum apparent velocity increment in the sampling period of the active segment is used to avoid the problem of outliers output by adding tables. The axial apparent velocity increment and the cumulative zero point of W _Nx1 are the ignition moment of the engine. The calculation method is:

${\mathrm{<span\; class="notranslate">\; W</span>}}_{\mathrm{<span\; class="notranslate">\; nx</span>}\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; \&Sigma;\&Delta;</span>}{\stackrel{<span\; class="notranslate">\; \&OverBar;</span>}{\mathrm{<span\; class="notranslate">\; W</span>}}}_{\mathrm{<span\; class="notranslate">\; x</span>}\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; ;</span>$

俯仰程序角按轴向视速度累加和W_Nx1分段线性插值。根据W_Nx1插值俯仰程序角，其公式如下22) During the flight of the carrier, use the data sheet

The pitch program angle is accumulated according to the axial apparent velocity and W _Nx1 piecewise linear interpolation. Interpolate the pitch program angle according to W _Nx1 , the formula is as follows

进行合理性判别，即对程序角变化率进行限幅。如图4所示，为与图3相对应的时间-轴向视速度增量累加和曲线。图4为本发明由时间-俯仰程序角数据表到轴向视速度增量累加和-俯仰程序角数据表的转换方法，根据设好的时间-俯仰程序角，获得运载器的标称轨迹，并记录相应时刻的运载器轴向视速度增量累加和W。T表示时间，W表示视速度增量累加和。t₁、t₂为程序角变化率变化显著时刻，也为程序转弯段、定轴段、调姿段切换时刻，相应视速度增量累加和分别为W1、W2。三段俯仰程序角增量限幅值分别为其数值由运载器性能及设计要求决定。23) According to the vehicle performance, design requirements and trajectory form, adjust the pitch program angle obtained in step 22)

To judge the rationality, that is, to limit the rate of change of the program angle. As shown in FIG. 4 , it is the time-axis apparent velocity incremental sum curve corresponding to FIG. 3 . Fig. 4 is the conversion method of the present invention from the time-pitch program angle data table to the axial apparent velocity incremental accumulation and-pitch program angle data table, according to the set time-pitch program angle, the nominal track of the carrier is obtained, And record the accumulative sum W of the axial apparent velocity increment of the vehicle at the corresponding moment. T represents time, and W represents the cumulative sum of apparent velocity increments. t ₁ and t ₂ are the moments when the rate of change of program angle changes significantly, and also the switching moments of program turning section, fixed axis section, and attitude adjustment section, and the cumulative sums of corresponding apparent speed increments are W1 and W2 respectively. The three-stage pitch program angle increment limit values are respectively Its value is determined by the vehicle performance and design requirements.

计算公式为Pitch program angle increment limit value

The calculation formula is

对俯仰程序角

进行合理性判别:use

Pitch program angle

Make a reasonable judgment:

即为基于视加速度测量的主动段程序自适应纵向制导技术的出的程序指令，运载器在此指令导引下按照预定轨迹飞行。 is the pitch program angle command in the previous cycle,

It is the program command issued by the active segment program adaptive longitudinal guidance technology based on apparent acceleration measurement, and the vehicle will fly according to the predetermined trajectory under the guidance of this command.

The invention can also be applied to a vehicle with multi-stage engines, and according to different engine characteristics, corresponding standard program sequences are designed and generated based on theoretical parameters of apparent acceleration, so as to realize self-adaptive guidance. Its design process is the same as above.

The content that is not described in detail in the description of the present invention belongs to the well-known technology of those skilled in the art.

Claims (4)

1. an active segment program adaptive longitudinal guidance method based on apparent acceleration measurement, characterized in that the steps are as follows: 1) Generate a standard program sequence based on the theoretical parameters of apparent acceleration; 11) Select the axial direction of the vehicle as the axis of apparent acceleration measurement; 12) Substitute the preset time-pitch program angle sequence into the dynamic model of the vehicle to obtain the nominal trajectory of the vehicle; according to the nominal trajectory, obtain the cumulative sum of the axial apparent velocity increments and the pitch program angle of the active section of the vehicle ; 13) Make a graph of the accumulated axial apparent speed increment and - pitch program angle, select the table interval according to the control accuracy threshold, and establish the accumulated axial apparent speed increment and - pitch program angle table as a standard program sequence; 14) In the launch preparation stage of the vehicle, the axial apparent velocity incremental accumulation and -pitch program angle table are bound in the form of various elements; 2) According to the measured apparent acceleration measurement, adaptive guidance is performed based on the standard program sequence; 21) After judging the rationality of the apparent acceleration measurement and eliminating the outliers, the cumulative sum of the axial apparent velocity increments is obtained; 22) During the flight of the vehicle, use the cumulative sum of axial apparent velocity increments obtained in step 21) to perform linear interpolation on the cumulative sum of axial apparent velocity increments - pitch program angle data table to obtain the pitch program angle; 23) Judge the rationality of the pitch program angle obtained in step 22) according to the preset program angle change rate amplitude, and use the judged pitch program angle command to control the vehicle to fly according to the predetermined trajectory. 2. An active segment program adaptive longitudinal guidance method based on apparent acceleration measurement according to claim 1, characterized in that: in step 13), segmental fitting parameters can also be selected according to the control accuracy threshold, and the fitting is established Parameters Table. 3. A method for adaptive longitudinal guidance based on apparent acceleration measurement in the active segment according to claim 1, characterized in that: step 21) judge the rationality of the measured amount of apparent acceleration, and obtain the axial visual field after eliminating outliers The specific method of accumulating the speed increment is as follows: 211) Discriminate the rationality of the axial apparent velocity increment ΔW _x1 , and obtain the judged axial apparent velocity increment

In the formula

is the axial apparent velocity increment after rationality judgment,

is the apparent speed increment of the previous cycle

is the value of the maximum apparent velocity increment within the sampling period of the active segment; 212) According to the judged axial apparent velocity increment obtained in step 211)

Get the axial apparent velocity delta and

The accumulative zero point is the ignition time of the engine. 4. A method for adaptive longitudinal guidance based on apparent acceleration measurement in the active segment according to claim 1, characterized in that: in step 23), the specific method for judging the rationality of the pitch program angle obtained in step 22) is as follows : 231) Obtain the limit value of pitch program angle increment

In the formula, W1 and W2 are respectively the cumulative sum of apparent velocity increments corresponding to the angular velocity limit conversion point of the pitch program;

Respectively, the pitch program angle increment limit value of each segment; 232) Use pitch program angle increment limit value Pitch program angle

Make a reasonable judgment:

In the formula is the pitch program angle command in the previous cycle, It is the program command obtained by the active segment program adaptive longitudinal guidance technology based on apparent acceleration measurement, that is, the pitch program angle command after discrimination.

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