A method and system for controlling flight status in real time in a tabular form

Abstract

The present application discloses a method and system for controlling the flight status in a tabular form in real time, wherein the method for controlling the flight status in a tabular form in real time specifically includes the following steps: obtaining the real-time flight status of the rocket; calculating the current point altitude and the current point speed according to the real-time flight status of the rocket; judging whether the current altitude and speed meet the reentry point conditions; if the reentry point conditions are met, obtaining the reentry point quality parameters, and obtaining the real-time values ​​of the key parameters of the reentry trajectory according to the obtained reentry point quality parameters; obtaining the reentry continuous trajectory according to the real-time values ​​of the key parameters of the reentry trajectory; and performing closed-loop real-time control of the real-time flight status of the rocket according to the reentry continuous trajectory. The present application can refine the reentry trajectory using a tabular method, can effectively reduce the amount of data storage on the arrow, and at the same time improve the calculation efficiency on the arrow.

Description

Technical Field

[0001] The present application relates to the field of rockets, and in particular, to a method and system for tabular real-time control of flight status. Background Art

[0002] At present, the reentry trajectory adopts the nominal program angle, which is designed offline without considering the interference and deviation in the actual flight process. The offline nominal designed program angle is used as the reentry reference trajectory for guided flight. When the program angle is controlled according to the offline nominal design, the position and velocity errors accumulated in the ascent phase will be brought into the reentry point error. During the reentry flight, the aerodynamic deviation and wind interference will cause large deviations in the landing point position and velocity, and only the recovery accuracy within a larger range can be achieved.

[0003] Therefore, how to provide a flight state control method that can improve the re-entry trajectory energy planning accuracy and thus improve landing accuracy is a problem that technical personnel in this field urgently need to solve. Summary of the invention

[0004] The present application provides a method for real-time control of flight status in a tabular form, which specifically includes the following steps: obtaining the real-time flight status of a rocket; calculating the current point altitude and the current point speed according to the real-time flight status of the rocket; judging whether the current altitude and speed meet the re-entry point conditions; if the re-entry point conditions are met, obtaining the re-entry point quality parameters, and obtaining the real-time values ​​of the key parameters of the re-entry trajectory according to the obtained re-entry point quality parameters; obtaining the re-entry continuous trajectory according to the real-time values ​​of the key parameters of the re-entry trajectory; and performing closed-loop real-time control of the real-time flight status of the rocket according to the re-entry continuous trajectory.

[0005] As mentioned above, the real-time flight status of the rocket specifically includes the current period inertial system position and the current period inertial system speed.

[0006] As above, the real-time flight status of the rocket specifically includes the current period inertial system position Current period inertial system speed Respectively expressed as:

[0007]

[0008]

[0009] in is the inertial system position of the current period, is the inertial system position of the previous period, is the inertial system velocity of the current period, is the inertial system velocity of the previous cycle, is the gravitational acceleration at the current period position, is the gravitational acceleration at the location in the previous cycle, ΔW is the apparent velocity increment of the inertial system in the current cycle, and T is the control period.

[0010] As above, before obtaining the current point height, it also includes calculating the rocket position geocentric vector diameter, where the rocket position geocentric vector diameter Specifically expressed as:

[0011]

[0012] in is the inertial system position of the current period, is the launch point radius vector.

[0013] As above, the current point height h is specifically expressed as:

[0014]

[0015] in The rocket's position is represented by the earth's center vector. Take the model, The radius vector of the launch point Taking the mold

[0016] As above, the current point speed v is specifically expressed as: That is to say, the velocity v of the current point is obtained by taking the modulus of the velocity of the inertial system of the current period.

[0017] As above, wherein obtaining the re-entry point quality parameter, and obtaining the real-time values ​​of the key parameters of the re-entry trajectory according to the obtained re-entry point quality parameter, comprises the following sub-steps: obtaining the re-entry point quality parameter; obtaining the re-entry point quality parameter increment according to the re-entry point quality parameter; obtaining a pre-designed re-entry trajectory interpolation table; obtaining the boundary values ​​of the re-entry trajectory interpolation table according to the re-entry point quality parameter and the re-entry point quality parameter increment; obtaining the real-time values ​​of the key parameters in the re-entry trajectory interpolation table according to the boundary values ​​of the re-entry trajectory interpolation table.

[0018] As above, the reentry trajectory interpolation table contains 27 rows and includes a height column H re -ΔH, H re , H re +ΔH, velocity column V re -ΔV, V re 、V re +ΔV, mass column m 0re -Δm0、m 0re 、m 0re +Δm0, where V re is the nominal design value of the reentry point, ΔV is the speed judgment threshold, H re is the nominal design value of the reentry point height, ΔH is the height judgment threshold, m0 is the reentry point quality parameter, m0re is the design value of the re-entry point quality parameter. Δm0 is the difference between the re-entry point quality parameter m0 and the design value m 0re increment.

[0019] As above, where the boundary values ​​are specifically the boundary values ​​of the current point height h, the current point velocity v, and the current mass m0 in the reentry trajectory interpolation table, which are specifically obtained by the following equation:

[0020]

[0021] Among them (H re -ΔH,H re ) is the boundary value of the current point height h, (V re -ΔV, V re ) is the boundary value of the Sangqian point velocity, (m 0re , m 0re +Δm0) is the boundary value of the reentry point quality parameter m0, H re is the nominal design value of the reentry point height, V re is the nominal design value of the reentry point velocity, m 0re is the nominal design value of the re-entry point mass, ΔH is the height judgment threshold, ΔV is the velocity judgment threshold, and Δm0 is the re-entry point mass parameter increment.

[0022] A system for controlling flight status in a tabular form in real time specifically comprises a flight status acquisition unit, a prediction unit, a judgment unit, a reentry trajectory key parameter acquisition unit, a reentry reference trajectory acquisition unit and a control unit; the flight status acquisition unit is used to acquire the real-time flight status of a rocket; the prediction unit is used to predict the current point altitude and the current point speed according to the real-time flight status of the rocket; the judgment unit is used to judge whether the reentry point altitude and the speed meet the reentry point conditions; the reentry trajectory key parameter acquisition unit is used to acquire the reentry point mass parameter if the reentry point conditions are met, and acquire the real-time value of the reentry trajectory key parameter according to the acquired reentry point mass parameter; the reentry reference trajectory acquisition unit is used to acquire the reentry continuous trajectory according to the real-time value of the reentry trajectory key parameter; the control unit is used to perform closed-loop real-time control on the real-time flight status of the rocket according to the reentry continuous trajectory.

[0023] This application has the following beneficial effects:

[0024] (1) The present application can refine the reentry trajectory using a tabular method, which can effectively reduce the amount of data stored on the arrow and improve the calculation efficiency on the arrow.

[0025] (2) This application uses altitude and speed as reference values ​​in closed-loop control, and performs state retrieval in conjunction with flight time to improve the robustness of state feedback, thereby improving control accuracy.

[0026] (3) Using dynamics to propose a continuous polynomial to form a reference trajectory, which can provide an accurate reentry trajectory BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present application. For ordinary technicians in this field, other drawings can also be obtained based on these drawings.

[0028] Figure 1 is a flow chart of a method for tabular real-time control of flight status provided in accordance with an embodiment of the present application;

[0029] Figure 2 It is an internal structure diagram of a system for controlling flight status in a tabular form in real time according to an embodiment of the present application. DETAILED DESCRIPTION

[0030] The following is a clear and complete description of the technical solutions in the embodiments of the present application in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present application.

[0031] The present application relates to a method and system for controlling the flight state in a tabular form in real time, which specifically adopts online calculation of reentry point quality parameters, interpolates key parameters according to a standard design state table, and forms a reentry reference trajectory for guidance calculation. The storage amount on the arrow can be reduced, and the calculation time on the arrow can be shortened. The online calculation of characteristic parameters according to the reentry point quality parameters can improve the energy planning accuracy of the reentry trajectory, thereby improving the landing accuracy.

[0032] Embodiment 1

[0033] like Figure 1 As shown, a method for controlling the flight status in a tabular form in real time provided by the present application specifically includes the following steps:

[0034] Step S110: Obtain the real-time flight status of the rocket.

[0035] Specifically, the inertial recursive algorithm is used to calculate the rocket body motion in real time. The real-time flight status of the rocket specifically includes the current period inertial system position Current period inertial system speed Equal amount.

[0036] The real-time flight status of the rocket specifically includes the current period inertial system position Current period inertial system speed Respectively expressed as:

[0037]

[0038]

[0039] in is the inertial system position of the current period, is the inertial system position of the previous period, is the inertial system velocity of the current period, is the inertial system velocity of the previous cycle, is the gravitational acceleration at the current period position, is the gravitational acceleration at the location in the previous cycle, ΔW is the apparent velocity increment of the inertial system in the current cycle, and T is the control period.

[0040] Step S120: Obtain the current point altitude and current point speed according to the real-time flight status of the rocket.

[0041] Before obtaining the current point height h, first calculate the rocket position geocentric vector radius Then the rocket position geocentric radius Get the current point height h, which is specifically expressed as:

[0042]

[0043]

[0044] in is the inertial system position of the current period, is the launch point radius vector, is the rocket's position geocentric vector, and h is the rocket's current flight altitude. The rocket's position is represented by the earth's center radius. Take the model, The radius vector of the launch point Take the model.

[0045] The current point speed v is specifically expressed as: That is to say, the velocity v of the current point is obtained by taking the modulus of the velocity of the inertial system of the current period.

[0046] Step S130: Determine whether the current altitude and speed meet the re-entry point conditions.

[0047] It determines whether the current point height h and the current point speed v meet the specified threshold. If they meet the specified threshold, the re-entry condition is met.

[0048] The specific method for determining whether the current point height h and the current point speed v meet the specified threshold is to determine whether the current point height h and the current point speed v meet the specified threshold. Among them, H re is the nominal design value of the reentry point height, V re is the nominal design value of the reentry point velocity, m 0re is the nominal design value of the reentry point mass, which is determined according to the flight mission. ΔH and ΔV are the altitude and speed judgment thresholds, respectively.

[0049] If the current point height h and the current point velocity v satisfy This indicates that the current point height h and the current point velocity v meet the re-entry point condition, and step S140 is executed; otherwise, step S110 is executed again.

[0050] Step S140: obtaining re-entry point quality parameters, and obtaining real-time values ​​of key parameters of the re-entry trajectory according to the obtained re-entry point quality parameters.

[0051] The execution of step S140 specifically includes the following sub-steps:

[0052] Step S1401: Obtain re-entry point quality parameters.

[0053] The re-entry point mass parameter is the current mass of the rocket m0.

[0054] Specifically, according to the remaining propellant mass at the time of shutdown and considering the evaporation amount in the gliding phase, the current mass of the rocket m0 is obtained.

[0055] Step S1402: Obtain a re-entry point quality parameter increment according to the re-entry point quality parameter.

[0056] Specifically, according to the reentry point mass parameter m0 and the rocket mass design value m 0re Get the current reentry point mass parameter m0 and the design value m of the rocket 0re The increment Δm0. The design value of the rocket mass is m 0re A pre-set value.

[0057] Step S1403: Obtain a pre-designed reentry trajectory interpolation table.

[0058] As shown in Table 1, the reentry trajectory interpolation table contains 27 rows and includes a height column H re -ΔH, H re , H re +ΔH, velocity column V re -ΔV, V re 、V re +ΔV, mass column m 0re -Δm0、m 0re 、m 0re+Δm0, where each 1-9 rows is a group of speed columns, each 1-3 rows is a group of speed columns, and each 1-3 rows is a group of mass columns. The key parameters ae in the table all have pre-set fixed values. In this embodiment, only a few parameters are added as examples. For example, the key parameter a contains the data 0.365, 0.36 and 0.4 in rows 1-3.

[0059] Table 1

[0060]

[0061] Step S1403 may be obtained before steps S1401-S1402, or after steps S1401-S1402.

[0062] Step S1404: Obtaining the boundary value of the re-entry trajectory interpolation table according to the re-entry point quality parameter and the re-entry point quality parameter increment.

[0063] Specifically, according to the current point height h and current point speed v obtained in step S120, and the current re-entry point quality parameter m0 and the re-entry point quality parameter increment Δm0 obtained in the current step, the boundary value of the re-entry trajectory interpolation table is obtained. The boundary value is specifically the boundary value of the current point height h, the current point speed v, and the current quality m0 in the re-entry trajectory interpolation table, and the boundary value is obtained by the following equation:

[0064]

[0065] Among them (H re -ΔH,H re ) is the boundary value of the current point height h, (V re -ΔV, V re ) is the boundary value of the Sangqian point velocity, (m 0re , m 0re +Δm0) is the boundary value of the re-entry point quality parameter m0.

[0066] Step S1405: According to the boundary values ​​of the re-entry trajectory interpolation table, the real-time values ​​of the key parameters in the re-entry trajectory interpolation table are obtained.

[0067] The current values ​​of height h, speed v, and mass m0 are distinguished and extracted respectively to obtain the uplink and downlink serial numbers of the key parameters. Based on the uplink and downlink data, linear interpolation is used to obtain the real-time value of the key parameter ae of the reentry trajectory.

[0068] Specifically, the row number is obtained, where first according to the boundary (H re -ΔH,H re ), filter out rows 1-27 to get rows 1-18. According to (V re -ΔV, V re) Filter rows 1-18 to get rows 1-6 and 10-15. According to the boundary (m 0re , m 0re +Δm0) in rows 1-6 and rows 10-15 were finally screened to obtain rows 2-3, rows 5-6, rows 11-12, and rows 14-15.

[0069] Further, in response to obtaining a specific row number, the data corresponding to the specific row number is obtained, and according to the current point height h, the current point speed v, the current mass m0, and the height column H re -ΔH, H re , H re +ΔH, velocity column V re -ΔV, V re 、V re +ΔV, mass column m 0re -Δm0、m 0re 、m 0re +Δm0 calculates the real-time values ​​of key parameters.

[0070] The calculation process of the real-time value of the key parameter a is as follows:

[0071] Take mass m0 as the independent variable to perform the first-dimensional interpolation calculation, a m-up_1 is the result of the first difference calculation in the first dimension, a m-low_2 is the result of the second difference calculation of the first dimension, a m_up_3 is the result of the third difference calculation of the first dimension, a m_low_4 This is the result of the fourth difference calculation in the first dimension.

[0072]

[0073]

[0074]

[0075]

[0076] Where m0 is the re-entry point quality parameter, m 0re is the design value of the re-entry point quality parameter. Δm0 is the difference between the re-entry point quality parameter m0 and the design value m 0reThe increment of . a[2], a[3], a[5], a[6], a

[11] , a

[12] , a

[14] , and a

[15] are the key parameter a column data corresponding to the 2nd to 3rd rows, 5th to 6th rows, 11th to 12th rows, and 14th to 15th rows, which are finally screened. Since rows 1 to 3 form a group of quality columns in the quality column, in the first-dimensional interpolation calculation, the data corresponding to the key parameter a in rows 2 to 3 are subjected to the first difference calculation of the first dimension, the data corresponding to the key parameter a in rows 5 to 6 are subjected to the second difference calculation of the first dimension, the data corresponding to the key parameter a in rows 11 to 12 are subjected to the third difference calculation of the first dimension, and the data corresponding to the key parameter a in rows 14 to 15 are subjected to the fourth difference calculation of the first dimension.

[0077] The second-dimensional interpolation calculation is performed with the current point velocity v as the independent variable, where a v_up is the result of the first difference calculation of the second dimension, a v_low This is the result of the second difference calculation in the second dimension.

[0078]

[0079]

[0080] where a m_up_1 is the result of the first difference calculation in the first dimension, a m_low_2 is the result of the second difference calculation of the first dimension, a m_up_3 is the result of the third difference calculation of the first dimension, a m_low_4 is the result of the fourth difference calculation of the first dimension, where V re is the nominal design value of the re-entry point, ΔV is the velocity judgment threshold, and v is the re-entry point velocity.

[0081] The third-dimensional interpolation calculation is performed with the current point height h as the independent variable, and the final real-time value of the key parameter a is obtained as a hvm . Among them a hvm Specifically expressed as:

[0082]

[0083] where a v_up is the result of the first difference calculation of the second dimension, a v_low is the result of the second difference calculation in the second dimension, H re is the nominal design value of the reentry point height, ΔH is the height judgment threshold, and h is the current point height.

[0084] The calculation process of the real-time value of the key parameter b is as follows:

[0085] The first dimension interpolation calculation is performed with mass m0 as the independent variable, b m_up_1 is the result of the first difference calculation in the first dimension, bm_low_2 is the result of the second difference calculation of the first dimension, b m_up_3 is the result of the third difference calculation of the first dimension, b m_low_4 This is the result of the fourth difference calculation in the first dimension.

[0086]

[0087]

[0088]

[0089]

[0090] Among them, b[2], b[3], b[5], b[6], b

[11] , b

[12] , b

[14] , and b

[15] are the data of the key parameter column b corresponding to rows 2-3, 5-6, 11-12, and 14-15 obtained by the final screening.

[0091] The second-dimensional interpolation calculation is performed with the current point velocity v as the independent variable, where b v_up is the result of the first difference calculation of the second dimension, b v_low This is the result of the second difference calculation in the second dimension.

[0092]

[0093]

[0094] The third-dimensional interpolation calculation is performed with the current point height h as the independent variable, and the final real-time value of the key parameter b is b hvm . Where b hvm Specifically expressed as:

[0095]

[0096] The calculation process of the real-time value of the key parameter c is as follows:

[0097] Take mass m0 as the independent variable to perform the first-dimensional interpolation calculation, c m_up_1 is the result of the first difference calculation in the first dimension, c m_low_2 is the result of the second difference calculation of the first dimension, c m_up_3 is the result of the third difference calculation of the first dimension, c m_low_4 This is the result of the fourth difference calculation in the first dimension.

[0098]

[0099]

[0100]

[0101]

[0102] Among them, c[2], c[3], c[5], c[6], c

[11] , c

[12] , c

[14] , and c

[15] are the data of the key parameter column c corresponding to rows 2-3, 5-6, 11-12, and 14-15 obtained by the final screening.

[0103] The second-dimensional interpolation calculation is performed with the current point velocity v as the independent variable, where c v_up is the result of the first difference calculation of the second dimension, c v_ l ow This is the result of the second difference calculation in the second dimension.

[0104]

[0105]

[0106] The third-dimensional interpolation calculation is performed with the current point height h as the independent variable, and the final real-time value of the key parameter c is obtained as c hvm . Where c hvm Specifically expressed as:

[0107]

[0108] The calculation process of the real-time value of the key parameter d is as follows:

[0109] The first dimension interpolation calculation is performed with mass m0 as the independent variable, d m_up_1 is the result of the first difference calculation of the first dimension, d m_low_2 is the result of the second difference calculation of the first dimension, d m_up_3 is the result of the third difference calculation of the first dimension, d m_low_4 This is the result of the fourth difference calculation in the first dimension.

[0110]

[0111]

[0112]

[0113]

[0114] Among them, d[2], d[3], d[5], d[6], d

[11] , d

[12] , d

[14] , and d

[15] are the data of the key parameter d column corresponding to rows 2-3, 5-6, 11-12, and 14-15 obtained by the final screening.

[0115] The second-dimensional interpolation calculation is performed with the current point velocity v as the independent variable, where d v_up is the result of the first difference calculation of the second dimension, d v_low This is the result of the second difference calculation in the second dimension.

[0116]

[0117]

[0118] The third-dimensional interpolation calculation is performed with the current point height h as the independent variable, and the final real-time value of the key parameter d is obtained as d hvm . Where d hvm Specifically expressed as:

[0119]

[0120] The calculation process of the real-time value of the key parameter e is as follows:

[0121] The first dimension interpolation calculation is performed with mass m0 as the independent variable, e m_up_1 is the result of the first difference calculation in the first dimension, e m_low_2 is the result of the second difference calculation of the first dimension, e m_up_3 is the result of the third difference calculation of the first dimension, e m_low_4 This is the result of the fourth difference calculation in the first dimension.

[0122]

[0123]

[0124]

[0125]

[0126] Among them, e[2], e[3], e[5], e[6], e

[11] , e

[12] , e

[14] , and e

[15] are the data of the key parameter e column corresponding to rows 2-3, 5-6, 11-12, and 14-15 obtained by the final screening.

[0127] The second-dimensional interpolation calculation is performed with the current point velocity v as the independent variable, where e v_up is the result of the first difference calculation of the second dimension, e v_low This is the result of the second difference calculation in the second dimension.

[0128]

[0129]

[0130] The third-dimensional interpolation calculation is performed with the current point height h as the independent variable, and the final real-time value of the key parameter e is obtained as e hvm . Where e hvm Specifically expressed as:

[0131]

[0132] Step S150: Obtain the reentry continuous trajectory according to the real-time values ​​of the key parameters of the reentry trajectory.

[0133] The real-time value of the key parameter ae of the polynomial coefficient extracted from the reentry trajectory spline curve can obtain the rocket's ideal reentry continuous trajectory. The rocket can then perform actual flight according to the reentry continuous trajectory.

[0134] Specifically, the reentry continuous trajectory includes the thrust value F that the engine needs to generate at time t under the ideal flight state of the rocket ref (t), the speed value V that the rocket needs to reach at time t ref (t) and the height H that the rocket needs to reach at time t ref (t).

[0135] F ref (t)=(a hvm ×t 4 +b hvm ×t 3 +c hvm ×t 2 +d hvm ×t+e hvm )×f1(h,v,m0)

[0136] V ref (t)=(a hvm ×t 4 +b hvm ×t 3 +c hvm ×t 2 +d hvm ×t+e hvm )×f2(h,v,m0)

[0137] H ref (t)=(a hvm ×t 4 +b hvm ×t 3 +c hvm ×t 2 +d hvm ×t+e hvm )×f3(h,v,m0)

[0138] Among them, h, v, m0 are the current point height, current point speed, and current mass respectively; Fref 、V ref , H ref is the reference thrust value, speed value, and altitude value, t is the flight time after the reentry point, f1, f2, and f3 are preset nominal functions and are determined items in the flight mission, and a hvm is the real-time value of key parameter a, b hvm is the real-time value of the key parameter b, c hvm is the real-time value of the key parameter c, d hvm is the real-time value of the key parameter d, e hvm is the real-time value of the key parameter e.

[0139] Step S160: Perform closed-loop real-time control on the real-time flight status of the rocket according to the re-entry continuous trajectory.

[0140] The rocket's flight is controlled in a closed loop and in real time according to the continuous re-entry trajectory.

[0141] Specifically, the current point height value h and the current point velocity value v are respectively compared with H in the reentry continuous trajectory ref (t) and V ref (t) is subtracted to obtain the deviation value. The flight state of the rocket is controlled in real time according to the deviation value, and then adjusted to the ideal landing speed and position. The adjustment is made specifically through the pitch angle command, yaw angle command, and the actual output thrust.

[0142] The control feedback can be solved as follows:

[0143]

[0144] in, is the pitch angle command, ψ is the yaw angle command, F represents the actual output thrust, D(z -1 ) is the control correction network, which is given by design; A ctrl (t) is the control allocation matrix; F ref (t) represents the thrust that the engine needs to generate at time t, V ref (t) represents the speed that the rocket needs to reach at time t, H ref (t) represents the height that the rocket needs to reach at time t, v represents the speed at the current point, and h represents the height at the current point.

[0145] The right side of the equation is F, The specific calculation results of and ψ are the expected values ​​of the flight state. The thrust, pitch angle command and yaw angle command in the real-time flight state are respectively approached to the thrust, pitch angle command and yaw angle command in the expected values ​​of the flight state, thereby performing closed-loop adjustment of the real-time flight state.

[0146] Embodiment 2

[0147] like Figure 2 As shown, the present application provides a tabular re-entry trajectory planning and guidance system, which specifically includes: a flight status acquisition unit 210, a prediction unit 220, a judgment unit 230, a re-entry trajectory key parameter acquisition unit 240, a re-entry reference trajectory acquisition unit 250, and a control unit 260.

[0148] The flight status acquisition unit 210 is used to acquire the real-time flight status of the rocket.

[0149] The prediction unit 220 is connected to the flight status acquisition unit 210 and is used to predict the current point altitude and the current point speed according to the real-time flight status of the rocket.

[0150] The judgment unit 230 is connected to the prediction unit 220 and is used to judge whether the current point height and the current point speed meet the re-entry point condition.

[0151] The re-entry trajectory key parameter acquisition unit 240 is connected to the judgment unit 230, and is used to obtain the re-entry point quality parameter if the re-entry point condition is met, and obtain the real-time value of the re-entry trajectory key parameter according to the obtained re-entry point quality parameter.

[0152] The re-entry reference trajectory acquisition unit 250 is connected to the re-entry trajectory key parameter acquisition unit 240, and is used to acquire the re-entry continuous trajectory according to the real-time values ​​of the re-entry trajectory key parameters.

[0153] The control unit 260 is connected to the flight state acquisition unit 210 and the re-entry reference trajectory acquisition unit 250 respectively, and is used to perform closed-loop real-time control on the real-time flight state of the rocket according to the re-entry continuous trajectory.

[0154] This application has the following beneficial effects:

[0155] (3) The present application can use a tabular method to refine the reentry trajectory, which can effectively reduce the amount of data stored on the arrow and improve the calculation efficiency on the arrow.

[0156] (4) The present application uses altitude and speed as reference values ​​in closed-loop control and performs state retrieval in conjunction with flight time to improve the robustness of state feedback, thereby improving control accuracy.

[0157] (5) The dynamics is used to propose a continuous polynomial to form a reference trajectory, which can provide an accurate reentry trajectory.

[0158] Although the present application is described with reference to examples, this is for illustrative purposes only and is not intended to limit the present application, and changes, additions and / or deletions to the embodiments may be made without departing from the scope of the present application.

[0159] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art who is familiar with the present technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims

1. A method for controlling flight status in real time in a tabular form, characterized in that: The specific steps include: Get the real-time flight status of the rocket; Calculate the current point height and current point speed according to the real-time flight status of the rocket; Determine whether the current altitude and speed meet the reentry point conditions; If the re-entry point conditions are met, the re-entry point quality parameters are obtained, and the real-time values ​​of the key parameters of the re-entry trajectory are obtained according to the obtained re-entry point quality parameters; Obtain the reentry continuous trajectory based on the real-time values ​​of the key parameters of the reentry trajectory; Closed-loop real-time control of the rocket's real-time flight status based on the reentry continuous trajectory; Obtaining the re-entry point quality parameters, and obtaining the real-time values ​​of the key parameters of the re-entry trajectory according to the obtained re-entry point quality parameters, includes the following sub-steps: Get the re-entry point quality parameter m0; Obtain a re-entry point quality parameter increment Δm0 according to the re-entry point quality parameter; Obtain a pre-designed reentry trajectory interpolation table; Obtaining a boundary value of a reentry trajectory interpolation table according to a reentry point quality parameter and a reentry point quality parameter increment; According to the boundary value of the reentry trajectory interpolation table, the real-time values ​​of the key parameters in the reentry trajectory interpolation table are obtained, wherein the current values ​​of the height h, speed v, and mass m0 are distinguished and extracted respectively, and the serial numbers of the uplink and downlink where the key parameters are located are obtained. According to the uplink and downlink data, the real-time values ​​of the key parameters ae of the reentry trajectory are obtained by linear interpolation; The calculation process of the real-time value of the key parameter a is as follows: Take mass m0 as the independent variable to perform the first-dimensional interpolation calculation, a m_up_1 is the result of the first difference calculation in the first dimension, a m_low_2 is the result of the second difference calculation of the first dimension, a m_up_3 is the result of the third difference calculation of the first dimension, a m_low_4 This is the result of the fourth difference calculation in the first dimension; Where m0 is the re-entry point quality parameter, m 0re is the design value of the re-entry point mass parameter, Δm0 is the difference between the re-entry point mass parameter m0 and the design value m 0re , a[2], a[3], a[5], a[6], a[11], a[12], a[14], and a[15] are the key parameter a column data corresponding to rows 2-3, 5-6, 11-12, and 14-15 obtained by the final screening. Since rows 1-3 are a group of quality columns in the quality column, in the first-dimensional interpolation calculation, the data corresponding to the key parameter a in rows 2-3 are subjected to the first difference calculation of the first dimension, the data corresponding to the key parameter a in rows 5-6 are subjected to the second difference calculation of the first dimension, the data corresponding to the key parameter a in rows 11-12 are subjected to the third difference calculation of the first dimension, and the data corresponding to the key parameter a in rows 14-15 are subjected to the fourth difference calculation of the first dimension; The second-dimensional interpolation calculation is performed with the current point velocity v as the independent variable, where a v_up is the result of the first difference calculation of the second dimension, a v_low This is the result of the second difference calculation for the second dimension; where a m_up_1 is the result of the first difference calculation in the first dimension, a m_low_2 is the result of the second difference calculation of the first dimension, a m_up_3 is the result of the third difference calculation of the first dimension, a m_low_4 is the result of the fourth difference calculation of the first dimension, where V re is the nominal design value of the re-entry point, ΔV is the velocity judgment threshold, and v is the re-entry point velocity; The third-dimensional interpolation calculation is performed with the current point height h as the independent variable, and the final real-time value of the key parameter a is obtained as a hvm , where a hvm Specifically expressed as: where a v_up is the result of the first difference calculation of the second dimension, a v_low is the result of the second difference calculation in the second dimension, H re is the nominal design value of the reentry point height, ΔH is the height judgment threshold, and h is the current point height; The calculation process of the real-time value of the key parameter b is as follows: The first dimension interpolation calculation is performed with mass m0 as the independent variable, b m_up_1 is the result of the first difference calculation in the first dimension, b m_low_2 is the result of the second difference calculation of the first dimension, b m_up_3 is the result of the third difference calculation of the first dimension, b m_low_4 This is the result of the fourth difference calculation in the first dimension; Among them, b[2], b[3], b[5], b[6], b[11], b[12], b[14], and b[15] are the data of the key parameter column b corresponding to the 2nd to 3rd rows, 5th to 6th rows, 11th to 12th rows, and 14th to 15th rows obtained by the final screening; The second-dimensional interpolation calculation is performed with the current point velocity v as the independent variable, where b v_up is the result of the first difference calculation of the second dimension, b v_low This is the result of the second difference calculation for the second dimension; The third-dimensional interpolation calculation is performed with the current point height h as the independent variable, and the final real-time value of the key parameter b is b hvm , where b hvm Specifically expressed as: The calculation process of the real-time value of the key parameter c is as follows: Take mass m0 as the independent variable to perform the first-dimensional interpolation calculation, c m_up_1 is the result of the first difference calculation in the first dimension, c m_low_2 is the result of the second difference calculation of the first dimension, c m_up_3 is the result of the third difference calculation of the first dimension, c m_low_4 This is the result of the fourth difference calculation in the first dimension; Among them, c[2], c[3], c[5], c[6], c[11], c[12], c[14], c[15] are the data of the key parameter c column corresponding to the 2nd-3rd row, 5th-6th row, 11th-12th row, and 14th-15th row obtained by the final screening; The second-dimensional interpolation calculation is performed with the current point velocity v as the independent variable, where c v_up is the result of the first difference calculation of the second dimension, c v_low This is the result of the second difference calculation for the second dimension; The third-dimensional interpolation calculation is performed with the current point height h as the independent variable, and the final real-time value of the key parameter c is obtained as c hvm , where c hvm Specifically expressed as: The calculation process of the real-time value of the key parameter d is as follows: The first dimension interpolation calculation is performed with mass m0 as the independent variable, d m_up_1 is the result of the first difference calculation of the first dimension, d m_low_2 is the result of the second difference calculation of the first dimension, d m_up_3 is the result of the third difference calculation of the first dimension, d m_low_4 This is the result of the fourth difference calculation in the first dimension; Among them, d[2], d[3], d[5], d[6], d[11], d[12], d[14], d[15] are the data of the key parameter column d corresponding to the 2nd to 3rd rows, 5th to 6th rows, 11th to 12th rows, and 14th to 15th rows obtained by the final screening; The second-dimensional interpolation calculation is performed with the current point velocity v as the independent variable, where d v_up is the result of the first difference calculation of the second dimension, d v_low This is the result of the second difference calculation for the second dimension; The third-dimensional interpolation calculation is performed with the current point height h as the independent variable, and the final real-time value of the key parameter d is obtained as d hvm , where d hvm Specifically expressed as: The calculation process of the real-time value of the key parameter e is as follows: The first dimension interpolation calculation is performed with mass m0 as the independent variable, e m_up_ 1 is the result of the first difference calculation in the first dimension, e m_low_2 is the result of the second difference calculation of the first dimension, e m_up_3 is the result of the third difference calculation of the first dimension, e m_low_4 This is the result of the fourth difference calculation in the first dimension; Among them, e[2], e[3], e[5], e[6], e[11], e[12], e[14], and e[15] are the data of the key parameter e column corresponding to the 2nd to 3rd rows, 5th to 6th rows, 11th to 12th rows, and 14th to 15th rows obtained by the final screening; The second-dimensional interpolation calculation is performed with the current point velocity v as the independent variable, where e v_up is the result of the first difference calculation of the second dimension, e v_low This is the result of the second difference calculation for the second dimension; The third-dimensional interpolation calculation is performed with the current point height h as the independent variable, and the final real-time value of the key parameter e is obtained as e hvm , where e hvm Specifically expressed as: The reentry trajectory interpolation table contains 27 rows and includes a height column H re -ΔH, H re , H re +ΔH, velocity column V re -ΔV, V re 、V re +ΔV, mass column m 0re -Δm0、m 0re 、m 0re +Δm0, where each 1-9 lines are a group of height columns, each 1-3 lines are a group of speed columns, and each 1-3 lines are a group of mass columns. The key parameters ae in the table all have pre-set fixed values; According to the real-time value of the key parameter ae of the polynomial coefficient extracted from the re-entry trajectory spline curve, the re-entry continuous trajectory of the rocket under the ideal state is obtained; The reentry continuous trajectory includes the thrust value F that the engine needs to generate at time t under the ideal flight state of the rocket ref (t), the speed value V that the rocket needs to reach at time t ref (t) and the height H that the rocket needs to reach at time t ref (t); F ref (t)=(a hvm ×t 4 +b hvm ×t 3 +c hvm ×t 2 +d hvm ×t+e hvm )×f1(h,v,m0) V ref (t)=(a hvm ×t 4 +b hvm ×t 3 +c hvm ×t 2 +d hvm ×t+e hvm )×f2(h,v,m0) H ref (t)=(a hvm ×t 4 +b hvm ×t 3 +c hvm ×t 2 +d hvm ×t+e hvm )×f3(h,v,m0) Among them, h, v, m0 are the current point height, current point speed, and current mass respectively; F ref 、V ref , H ref is the reference thrust value, speed value, and altitude value, t is the flight time after the reentry point, f1, f2, and f3 are preset nominal functions and are determined items in the flight mission, and a hvm is the real-time value of key parameter a, b hvm is the real-time value of the key parameter b, c hvm is the real-time value of the key parameter c, d hvm is the real-time value of the key parameter d, e hvm is the real-time value of the key parameter e.

2. The method for controlling the flight status in a tabular form in real time as claimed in claim 1, characterized in that: The real-time flight status of the rocket specifically includes the current period inertial system position and the current period inertial system speed.

3. The method for controlling the flight status in a tabular form in real time as claimed in claim 1, characterized in that: The real-time flight status of the rocket specifically includes the current period inertial system position Current period inertial system speed Respectively expressed as: in is the inertial system position of the current period, is the inertial system position of the previous period, is the inertial system velocity of the current period, is the inertial system velocity of the previous cycle, is the gravitational acceleration at the current period position, is the gravitational acceleration at the location in the previous cycle, ΔW is the apparent velocity increment of the inertial system in the current cycle, and T is the control period.

4. The method for controlling the flight status in a tabular form in real time as claimed in claim 3, characterized in that: Before obtaining the current point height, the rocket position geocentric vector radius is also calculated, where the rocket position geocentric vector radius Specifically expressed as: in is the inertial system position of the current period, is the launch point radius vector.

5. The method for controlling the flight status in a tabular form in real time as claimed in claim 4, characterized in that: The current point height h is specifically expressed as: in The rocket's position is represented by the earth's center radius. Take the model, The radius vector of the launch point Take the model.

6. The method for controlling the flight status in a tabular form in real time as claimed in claim 3, characterized in that: The current point speed v is specifically expressed as: That is to say, the velocity v of the current point is obtained by taking the modulus of the velocity of the inertial system of the current period.

7. The method for controlling the flight status in a tabular form in real time as claimed in claim 1, characterized in that: The boundary values ​​are specifically the boundary values ​​of the current point height h, the current point velocity v, and the current mass m0 in the reentry trajectory interpolation table, which are obtained by the following equations: Among them (H re -ΔH,H re ) is the boundary value of the current point height h, (V re -ΔV, V re ) is the boundary value of the current point velocity v, (m 0re , m 0re +Δm0) is the boundary value of the reentry point quality parameter m0, H re is the nominal design value of the reentry point height, V re is the nominal design value of the reentry point velocity, m 0re is the nominal design value of the re-entry point mass, ΔH is the height judgment threshold, ΔV is the velocity judgment threshold, and Δm0 is the re-entry point mass parameter increment.

8. A system for controlling flight status in a tabular form in real time, characterized in that: It includes a flight status acquisition unit, a prediction unit, a judgment unit, a reentry trajectory key parameter acquisition unit, a reentry reference trajectory acquisition unit and a control unit; A flight status acquisition unit, used to acquire the real-time flight status of the rocket; A prediction unit, used to predict the current point altitude and current point speed according to the real-time flight status of the rocket; A judgment unit, used to judge whether the current point height and the current point speed meet the re-entry point conditions; A reentry trajectory key parameter acquisition unit, used to acquire a reentry point quality parameter if the reentry point condition is met, and acquire a real-time value of the reentry trajectory key parameter based on the acquired reentry point quality parameter; A reentry reference trajectory acquisition unit, used to acquire a reentry continuous trajectory according to real-time values ​​of key parameters of the reentry trajectory; A control unit, used for closed-loop real-time control of the rocket's real-time flight status according to the reentry continuous trajectory; The reentry trajectory key parameter acquisition unit acquires the reentry point quality parameter, and acquires the real-time value of the reentry trajectory key parameter according to the acquired reentry point quality parameter, including the following sub-steps: Get the re-entry point quality parameter m0; Obtain a re-entry point quality parameter increment Δm0 according to the re-entry point quality parameter; Obtain a pre-designed reentry trajectory interpolation table; Obtaining a boundary value of a reentry trajectory interpolation table according to a reentry point quality parameter and a reentry point quality parameter increment; According to the boundary value of the reentry trajectory interpolation table, the real-time values ​​of the key parameters in the reentry trajectory interpolation table are obtained, wherein the current values ​​of the height h, speed v, and mass m0 are distinguished and extracted respectively, and the serial numbers of the uplink and downlink where the key parameters are located are obtained. According to the uplink and downlink data, the real-time values ​​of the key parameters ae of the reentry trajectory are obtained by linear interpolation; The calculation process of the real-time value of the key parameter a is as follows: Take mass m0 as the independent variable to perform the first-dimensional interpolation calculation, a m_up_1 is the result of the first difference calculation in the first dimension, a m_low_2 is the result of the second difference calculation of the first dimension, a m_up_3 is the result of the third difference calculation of the first dimension, a m_low_4 This is the result of the fourth difference calculation in the first dimension; Where m0 is the re-entry point quality parameter, m 0re is the design value of the re-entry point mass parameter, Δm0 is the difference between the re-entry point mass parameter m0 and the design value m 0re , a[2], a[3], a[5], a[6], a[11], a[12], a[14], and a[15] are the key parameter a column data corresponding to rows 2-3, 5-6, 11-12, and 14-15 obtained by the final screening. Since rows 1-3 are a group of quality columns in the quality column, in the first-dimensional interpolation calculation, the data corresponding to the key parameter a in rows 2-3 are subjected to the first difference calculation of the first dimension, the data corresponding to the key parameter a in rows 5-6 are subjected to the second difference calculation of the first dimension, the data corresponding to the key parameter a in rows 11-12 are subjected to the third difference calculation of the first dimension, and the data corresponding to the key parameter a in rows 14-15 are subjected to the fourth difference calculation of the first dimension; The second-dimensional interpolation calculation is performed with the current point velocity v as the independent variable, where a v_up is the result of the first difference calculation of the second dimension, a v_low This is the result of the second difference calculation for the second dimension; where a m_up_1 is the result of the first difference calculation in the first dimension, a m_low_2 is the result of the second difference calculation of the first dimension, a m_up_3 is the result of the third difference calculation of the first dimension, a m_low_4 is the result of the fourth difference calculation of the first dimension, where V re is the nominal design value of the re-entry point, ΔV is the velocity judgment threshold, and v is the re-entry point velocity; The third-dimensional interpolation calculation is performed with the current point height h as the independent variable, and the final real-time value of the key parameter a is obtained as a hvm , where a hvm Specifically expressed as: where a v_up is the result of the first difference calculation of the second dimension, a v_low is the result of the second difference calculation in the second dimension, H re is the nominal design value of the reentry point height, ΔH is the height judgment threshold, and h is the current point height; The calculation process of the real-time value of the key parameter b is as follows: The first dimension interpolation calculation is performed with mass m0 as the independent variable, b m_up_1 is the result of the first difference calculation in the first dimension, b m_low_2 is the result of the second difference calculation of the first dimension, b m_up_3 is the result of the third difference calculation of the first dimension, b m_low_4 This is the result of the fourth difference calculation in the first dimension; Among them, b[2], b[3], b[5], b[6], b[11], b[12], b[14], and b[15] are the data of the key parameter column b corresponding to the 2nd to 3rd rows, 5th to 6th rows, 11th to 12th rows, and 14th to 15th rows obtained by the final screening; The second-dimensional interpolation calculation is performed with the current point velocity v as the independent variable, where b v_up is the result of the first difference calculation of the second dimension, b v_low This is the result of the second difference calculation for the second dimension; The third-dimensional interpolation calculation is performed with the current point height h as the independent variable, and the final real-time value of the key parameter b is b hvm , where b hvm Specifically expressed as: The calculation process of the real-time value of the key parameter c is as follows: Take mass m0 as the independent variable to perform the first-dimensional interpolation calculation, c m_up_1 is the result of the first difference calculation in the first dimension, c m_low_2 is the result of the second difference calculation of the first dimension, c m_up_3 is the result of the third difference calculation of the first dimension, c m_low_4 This is the result of the fourth difference calculation in the first dimension; Among them, c[2], c[3], c[5], c[6], c[11], c[12], c[14], c[15] are the data of the key parameter c column corresponding to the 2nd-3rd row, 5th-6th row, 11th-12th row, and 14th-15th row obtained by the final screening; The second-dimensional interpolation calculation is performed with the current point velocity v as the independent variable, where c v_up is the result of the first difference calculation of the second dimension, c v_low This is the result of the second difference calculation for the second dimension; The third-dimensional interpolation calculation is performed with the current point height h as the independent variable, and the final real-time value of the key parameter c is obtained as c hvm , where c hvm Specifically expressed as: The calculation process of the real-time value of the key parameter d is as follows: The first dimension interpolation calculation is performed with mass m0 as the independent variable, d m_up_1 is the result of the first difference calculation of the first dimension, d m_low_2 is the result of the second difference calculation of the first dimension, d m_up_3 is the result of the third difference calculation of the first dimension, d m_low_4 This is the result of the fourth difference calculation in the first dimension; Among them, d[2], d[3], d[5], d[6], d[11], d[12], d[14], d[15] are the data of the key parameter column d corresponding to the 2nd to 3rd rows, 5th to 6th rows, 11th to 12th rows, and 14th to 15th rows obtained by the final screening; The second-dimensional interpolation calculation is performed with the current point velocity v as the independent variable, where d v_up is the result of the first difference calculation of the second dimension, d v_low This is the result of the second difference calculation for the second dimension; The third-dimensional interpolation calculation is performed with the current point height h as the independent variable, and the final real-time value of the key parameter d is obtained as d hvm , where d hvm Specifically expressed as: The calculation process of the real-time value of the key parameter e is as follows: The first dimension interpolation calculation is performed with mass m0 as the independent variable, e m_up_1 is the result of the first difference calculation in the first dimension, e m_low_2 is the result of the second difference calculation of the first dimension, e m_up_3 is the result of the third difference calculation of the first dimension, e m_low_4 This is the result of the fourth difference calculation in the first dimension; Among them, e[2], e[3], e[5], e[6], e[11], e[12], e[14], and e[15] are the data of the key parameter e column corresponding to the 2nd to 3rd rows, 5th to 6th rows, 11th to 12th rows, and 14th to 15th rows obtained by the final screening; The second-dimensional interpolation calculation is performed with the current point velocity v as the independent variable, where e v_up is the result of the first difference calculation of the second dimension, e v_low This is the result of the second difference calculation for the second dimension; The third-dimensional interpolation calculation is performed with the current point height h as the independent variable, and the final real-time value of the key parameter e is obtained as e hvm , where e hvm Specifically expressed as: The reentry trajectory interpolation table contains 27 rows and includes a height column H re -ΔH, H re , H re +ΔH, velocity column V re -ΔV, V re 、V re +ΔV, mass column m 0re -Δm0、m 0re 、m 0re +Δm0, where each 1-9 lines are a group of height columns, each 1-3 lines are a group of speed columns, and each 1-3 lines are a group of mass columns. The key parameters ae in the table all have pre-set fixed values; According to the real-time value of the key parameter ae of the polynomial coefficient extracted from the re-entry trajectory spline curve, the re-entry continuous trajectory of the rocket under the ideal state is obtained; The reentry continuous trajectory includes the thrust value F that the engine needs to generate at time t under the ideal flight state of the rocket ref (t), the speed value V that the rocket needs to reach at time t ref (t) and the height H that the rocket needs to reach at time t ref (t); F ref (t)=(a hvm ×t 4 +b hvm ×t 3 +c hvm ×t 2 +d hvm ×t+e hvm )×f1(h,v,m0) V ref (t)=(a hvm ×t 4 +b hvm ×t 3 +c hvm ×t 2 +d hvm ×t+e hvm )×f2(h,v,m0) H ref (t)=(a hvm ×t 4 +b hvm ×t 3 +c hvm ×t 2 +d hvm ×t+e hvm )×f3(h,v,m0) Among them, h, v, m0 are the current point height, current point speed, and current mass respectively; F ref 、V ref , H ref is the reference thrust value, speed value, and altitude value, t is the flight time after the reentry point, f1, f2, and f3 are preset nominal functions and are determined items in the flight mission, and a hvm is the real-time value of key parameter a, b hvm is the real-time value of the key parameter b, c hvm is the real-time value of the key parameter c, d hvm is the real-time value of the key parameter d, e hvm is the real-time value of the key parameter e.

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