CN103486905B - Determining method for terminal guidance shift-exchange conditions of reenter vehicle - Google Patents

Abstract

The invention discloses a determining method for terminal guidance shift-exchange conditions of a reenter vehicle. The determining method includes (1), generating preset shift-exchange point information; (2), correcting the preset shift-exchange point information generated in step (1), and generating a preset shift-exchange point error ball; (3), designing guidance gain which is changeable with time; (4), determining a command smoothing time factor sequence sorted according to time; (5), determining shift-exchange logic, starting terminal guidance of a seeker when the shift-exchange logic is completely met; (6), in the process of midcourse guidance flight of the reenter vehicle, performing midcourse guidance by the aid of the guidance gain, which is changeable with the time, determined in step (3), judging whether the shift-exchange logic determined in step (5) is met or not in real time, starting the terminal guidance of the seeker when the shift-exchange logic is met, picking a factor from the command smoothing time factor sequence determined in step (4) according to order, performing smoothing on the midcourse guidance and the terminal guidance by the factor, performing guidance according to a command subjected to smoothing, and shifting to the simple terminal guidance of the seeker after preset time is reached.

Description

A kind of reentry vehicle terminal guidance hand-over condition defining method

Technical field

The invention belongs to armament systems design field, relate to a kind of reentry vehicle terminal guidance hand-over condition defining method.The present invention is mainly used in the middle terminal guidance hand-over condition Design and implementation reentering precision strike aircraft, to guarantee payload attack precision.

Background technology

Have the features such as height is dynamic, multiple constraint for reentry vehicle, these characteristics are particularly important for the aircraft with terminal guidance ability.The reentry vehicle with terminal guidance ability needs to experience velocity variations in a big way and height change, and comparatively harsh to the performance requirement of guidance control system, ordinary circumstance, midcourse guidance and terminal guidance adopt different guidance systems.After middle terminal guidance is handed over to the next shift, by target seeker information measurement position of aircraft, so terminal guidance precision conditions and speed, angle restriction will be ensured, the terminal guidance of high-reliability just must be adopted to hand over to the next shift system.Therefore, it is a kind of high reliability, high-precision flight Guidance and control pattern, brings many brand-new challenges and difficulty to control system.

Summary of the invention

Technology of the present invention is dealt with problems and is: overcome the deficiencies in the prior art, provides a kind of reentry vehicle terminal guidance hand-over condition defining method.

Technical solution of the present invention is: a kind of reentry vehicle terminal guidance hand-over condition defining method, and step is as follows:

(1) according to given initial reentry point and the information that strikes target, planning reentry trajectory, generate preset dot information of handing over to the next shift, described dot information of handing over to the next shift comprises the position in moment of handing over to the next shift, velocity magnitude, trajectory tilt angle, trajectory deflection angle, sight line turning rate;

(2) according to reentry vehicle target seeker terminal guidance condition of work, to the preset dot information correction of handing over to the next shift generated in step (1), and according to navigation and positioning accuracy and the requirement of terminal guidance accuracy at target, preset point tolerance ball of handing over to the next shift is generated;

(3) before handing over to the next shift, reentry vehicle guidance control system adopts variable-gain homing guidance rule, with preset dot information of handing over to the next shift revised in step (2) for end conswtraint, designs time dependent guidance gain;

(4) follow the tracks of midcourse guidance instruction and target seeker from homing control instruction according to step (3) variable-gain, difference is asked and analysis and Control system responses to two groups of instructions, determines the instruction smoothingtime coefficient sequence according to time-sequencing;

(5) determine according to hand over to the next shift a position and speed and error ball, hand over to the next shift a LOS guidance and velocity attitude logic of handing over to the next shift; When completely meet hand over to the next shift logic time, target seeker terminal guidance start;

(6) in reentry vehicle midcourse guidance flight course, midcourse guidance is carried out in the time dependent guidance gain adopting step (3) to determine, and whether real-time judge meets the logic of handing over to the next shift determined in step (5) simultaneously, when meet hand over to the next shift logic time, start target seeker terminal guidance, and value in the instruction smoothingtime coefficient sequence determined from step (4) in order, this coefficient centering is utilized to guidance command process smoothing with terminal guidance instruction, and utilize the instruction after smoothing processing to guide, proceed to simple target seeker terminal guidance after reaching default time.

Described logic of handing over to the next shift comprises hand over to the next shift a position and speed and error ball combination condition and hand over to the next shift a LOS guidance and velocity attitude combination condition; Wherein a hand over to the next shift position and speed and error ball combination condition is:

||r ^*-r _c||<K _r·||δr _c||+K _v·δv _c

Wherein, r ^*for practical flight device position, r _cfor the revised preset position of handing over to the next shift of step (2), δ r _cfor preset site error of handing over to the next shift in point tolerance ball, δ v _cfor preset velocity error of handing over to the next shift in point tolerance ball, K _r, K _verror coefficient; || || representative vector asks mould;

A hand over to the next shift LOS guidance and velocity attitude combination condition is:

cos ^-1(cosθ ^*cosψ ^*)<K _θ·cos ^-1(cosθ _ccosψ _c)+K _ω(ω _LOS-ω _LOSC)

Wherein, θ ^*, ψ ^*for actual trajectory inclination angle and trajectory deflection angle, θ _c, ψ _cfor preset trajectory tilt angle and trajectory deflection angle, K _θ, K _ωfor error coefficient.

The present invention compared with prior art beneficial effect is:

(1) terminal guidance that the invention solves complex condition is handed over to the next shift problem, enhances the fault-tolerant ability of guidance system.First calculate preset dot information of handing over to the next shift by initial information, target information, and utilize target seeker terminal guidance condition of work to revise it.And then by variable gain, instruction smoothing factor and multiple condition decision logic, prevent hand over to the next shift status command step, sudden change, improve the reliability that armament systems are handed over to the next shift, the unnecessary links such as the instruction hardware limit of armament systems can be reduced.

(2) the inventive method can solve terminal guidance reentry vehicle hand-over condition problem complicated and changeable, enhances the robustness of scheme, improves the fault-tolerant ability of guidance system.

(3) the present invention's design is containing the logic of handing over to the next shift of error, and moment flight state of guaranteeing to hand over to the next shift meets target seeker contact conditions, for armament systems terminal guidance provides advantage.

(4) in the present invention, terminal guidance is handed over to the next shift and is designed instruction smoothing factor sequence, prevents hand over to the next shift status command step, sudden change, improves the reliability that armament systems are handed over to the next shift, can reduce the unnecessary links such as the instruction hardware limit of armament systems.

Accompanying drawing explanation

Fig. 1 is the inventive method flow chart;

Fig. 2 is that the preset dot information of handing over to the next shift of the present invention generates and makeover process figure;

Fig. 3 is that the present invention to hand over to the next shift and requires and a design objective graph of a relation;

Fig. 4 is terminal guidance instruction smooth operation procedure chart of the present invention.

Detailed description of the invention

Below in conjunction with drawings and Examples, the present invention will be further described.

As shown in Figure 1, the present invention relates to a kind of reentry vehicle terminal guidance hand-over condition defining method, concrete steps are as follows:

1, generate and presetly hand over to the next shift a little;

As shown in Figure 2, by given reentry point information (comprising position, velocity magnitude, speed inclination angle and attitude) and the information that strikes target (position of target, speed), setting reenters restrained boundary (hot-fluid, overload, dynamic pressure etc.), pass through simulant design, generate reentry vehicle longitudinal profile, be therefrom tentatively met the preset dot information of handing over to the next shift that flight requires.

The planning of reentry trajectory can adopt the reentry trajectory optimized algorithm based on the pseudo-spectrometry of Gauss conventional at present or sequential quadratic programming algorithm etc., the position in the moment of handing over to the next shift utilizing above-mentioned algorithm to calculate velocity magnitude trajectory tilt angle trajectory deflection angle sight line turning rate

2, revise and presetly hand over to the next shift a little and generate preset point tolerance ball of handing over to the next shift;

After tentatively obtaining preset dot information of handing over to the next shift, consider the constraint of target seeker contact conditions, mainly angle of visual field scope and angle of sight rate of rotation retrain, thus to preset dot information correction of handing over to the next shift, consider that catching boundary condition provides preset point tolerance ball of handing over to the next shift simultaneously.

The preset dot information of handing over to the next shift adopting step (1) to generate does not consider the effect of constraint value shown in Fig. 3, considers that emphatically target seeker contact conditions is revised the constraint that trajectory tilt angle, trajectory deflection angle and sight line turning rate cause.Choose the angle of visual field in target seeker contact conditions, angle of sight rate of rotation is object function, choosing trajectory tilt angle, trajectory deflection angle and sight line turning rate is design variable, adopt Quasi-Newton iterative method, what generate with step (1) presetly hands over to the next shift a little for iterative initial value, meeting the angle of visual field and angle of sight rate of rotation scope intermediate value in target seeker contact conditions is iteration stopping condition, completes preset dot information correction of handing over to the next shift.Get position of aircraft r when meeting iteration stopping condition _c, velocity magnitude v _c, trajectory tilt angle θ _c, trajectory deflection angle ψ _c, sight line turning rate ω _lOSCfor revised preset dot information of handing over to the next shift.

After revising, hand over to the next shift dot information for iterative initial value, other conditions of said method are constant, iteration stopping condition are set to and meet the angle of visual field and angle of sight rate of rotation up-and-down boundary, hand over to the next shift a position and speed and the revised preset position r that hands over to the next shift that calculate _cspeed v _cask poor, namely obtain preset position error delta r _c, preset speed error delta v _c, be called error ball.

3, variable-gain midcourse guidance is designed;

The instruction of design variable-gain midcourse guidance, guidance command the form can taking following formula:

δ _a=K·K _L·[Δr,Δv] ^T

Wherein Δ r, Δ v are respectively the difference of aircraft current location, speed and reference locus position, speed, K _lfor the guidance gain that LQR method obtains, K is variable gain.

Design variable gain K(is also known as the guidance gain of time variations)

$K=e^{\mathrm{\&alpha;}},\mathrm{\&alpha;}=-\frac{\left|\right|r^{*}-r_c\left|\right|}{\left|\right|r^{*}\left|\right|}-\frac{|v^{*}-v_c|}{\left|v^{*}\right|}$

Centering is guidanceed command and is made in flight course as gain process, neither affects the flying quality of midcourse guidance whole process, can arrive presetly to hand over to the next shift a little, can take into account again close to the steady demand of midcourse guidance instruction when to hand over to the next shift.

V ^*represent practical flight velocity magnitude, r ^*represent aerocraft real position vector, || || representative vector asks mould, || absolute value is asked in representative.

4, instruction smoothing factor sequence is determined;

As shown in Figure 4, hand over to the next shift according to standard condition, follow the tracks of midcourse guidance instruction δ for variable-gain in step (3) _aand target seeker is from homing control instruction δ _b, design the instruction smoothing factor sequence beta function according to time-sequencing

$\mathrm{\&beta;}=1-\frac{{\mathrm{\&delta;}}_a\left(t_0\right)}{{\mathrm{\&delta;}}_b\left(t_0\right)}{e}^{t-t_0}$

Wherein t ₀for meeting the logic target seeker start moment of handing over to the next shift, δ _a(t ₀) be this moment midcourse guidance instruction, δ _b(t ₀) be this moment terminal guidance instruction.

5, logic of handing over to the next shift is designed;

Logic of handing over to the next shift comprises two conditions:

First is hand over to the next shift a position and speed and error ball combination condition

||r ^*-r _c||<K _r·||δr _c||+K _v·δv _c

Wherein, r ^*for practical flight device position, r _cfor a revised preset position of handing over to the next shift, δ r _cfor preset position error, δ v _cfor preset speed error, K _r, K _vfor error coefficient, rule of thumb value, such as, be less than the aircraft of 3 Mach, K for spot speed of handing over to the next shift _rusual value 0.1 ~ 3, K _vbe generally K _r5 ~ 10 times, according to δ v _cit is adjusted.

Second is hand over to the next shift a LOS guidance and velocity attitude combination condition

cos ^-1(cosθ ^*cosψ ^*)<K _θ·cos ^-1(cosθ _ccosψ _c)+K _ω(ω _LOS-ω _LOSC)

Wherein, θ ^*, ψ ^*for actual trajectory inclination angle and trajectory deflection angle, θ _c, ψ _cfor revised trajectory tilt angle and trajectory deflection angle, K _θ, K _ωfor error coefficient, rule of thumb value, such as, be less than the situation of 5 °/s, K for a sight line turning rate of handing over to the next shift _rusual value 0.05 ~ 1, K _vbe generally K _r3 ~ 5 times.

When simultaneously meet two conditions time, target seeker terminal guidance start.

6, actual guidance

In reentry vehicle midcourse guidance flight course, midcourse guidance is carried out in the time dependent guidance gain adopting step (3) to determine, and whether real-time judge meets the logic of handing over to the next shift determined in step (5) simultaneously, when meet hand over to the next shift logic time, start target seeker terminal guidance, and value in the instruction smoothingtime coefficient sequence determined from step (4) in order, utilize the midcourse guidance instruction δ that this coefficient generates practical flight ^* _awith terminal guidance instruction δ ^* _bsmoothing process, and utilize the instruction δ after smoothing processing _cguide, after reaching default time, proceed to simple target seeker terminal guidance.

δ _c=β·δ ^* _a+(1-β)·δ ^* _b

Wherein, the time of presetting can be set to 5ms ~ 20s based on experience value.Also can when designing, directly according to the instruction smoothingtime coefficient sequence control time, when proceeding to simple target seeker terminal guidance after value to last coefficient in sequence in order.

In XX/terminal guidance hand-over condition design in, adopt the reentry vehicle terminal guidance hand-over condition defining method that the present invention describes, to achieve in certain weapon/the rapid Design of terminal guidance hand-over condition, verified by Six-degree-of-freedom Simulation, show that hand over to the next shift flow process and the hand-over condition adopting the method to determine can meet target seeker contact conditions.

The unspecified part of the present invention belongs to general knowledge as well known to those skilled in the art.

Claims (2)

1. a reentry vehicle terminal guidance hand-over condition defining method, is characterized in that step is as follows:

(1) according to given initial reentry point and the information that strikes target, planning reentry trajectory, generate preset dot information of handing over to the next shift, described dot information of handing over to the next shift comprises the position in moment of handing over to the next shift, velocity magnitude, trajectory tilt angle, trajectory deflection angle, sight line turning rate;

(2) according to reentry vehicle target seeker terminal guidance condition of work, to the preset dot information correction of handing over to the next shift generated in step (1), and according to navigation and positioning accuracy and the requirement of terminal guidance accuracy at target, preset point tolerance ball of handing over to the next shift is generated;

(3) before handing over to the next shift, reentry vehicle guidance control system adopts variable-gain homing guidance rule, with preset dot information of handing over to the next shift revised in step (2) for end conswtraint, designs time dependent guidance gain;

(4) follow the tracks of midcourse guidance instruction and target seeker from homing control instruction according to step (3) variable-gain, difference is asked and analysis and Control system responses to two groups of instructions, determines the instruction smoothingtime coefficient sequence according to time-sequencing;

(5) determine according to hand over to the next shift a position and speed and error ball, hand over to the next shift a LOS guidance and velocity attitude logic of handing over to the next shift; When completely meet hand over to the next shift logic time, target seeker terminal guidance start;

(6) in reentry vehicle midcourse guidance flight course, midcourse guidance is carried out in the time dependent guidance gain adopting step (3) to determine, and whether real-time judge meets the logic of handing over to the next shift determined in step (5) simultaneously, when meet hand over to the next shift logic time, start target seeker terminal guidance, and value in the instruction smoothingtime coefficient sequence determined from step (4) in order, this coefficient centering is utilized to guidance command process smoothing with terminal guidance instruction, and utilize the instruction after smoothing processing to guide, simple target seeker terminal guidance is proceeded to after reaching default time.

2. a kind of reentry vehicle terminal guidance hand-over condition defining method according to claim 1, is characterized in that: described logic of handing over to the next shift comprises hand over to the next shift a position and speed and error ball combination condition and hand over to the next shift a sight line turning rate and velocity attitude combination condition; Wherein a hand over to the next shift position and speed and error ball combination condition is:

||r ^*-r _c||<K _r·||δr _c||+K _v·δv _c

Wherein, r ^*for practical flight device position, r _cfor the revised preset position of handing over to the next shift of step (2), δ r _cfor preset site error of handing over to the next shift in point tolerance ball, δ v _cfor preset velocity error of handing over to the next shift in point tolerance ball, K _r, K _verror coefficient; || || representative vector asks mould;

A hand over to the next shift sight line turning rate and velocity attitude combination condition is:

cos ^-1(cosθ ^*cosψ ^*)<K _θ·cos ^-1(cosθ _ccosψ _c)+K _ω(ω _LOS-ω _LOSC)

Wherein, θ ^*, ψ ^*for actual trajectory inclination angle and trajectory deflection angle, θ _c, ψ _cfor preset trajectory tilt angle and trajectory deflection angle, K _θ, K _ωfor error coefficient.