CN102419181A - Autonomous non-overshoot state switching method of ship inertial navigation system - Google Patents

Abstract

The invention discloses an autonomous non-overshoot state switching method of a ship inertial navigation system, comprising the following steps of: determining the damping ratio of a correction link; determining the time domain parameter during the calibration process; determining the cut-off frequency during the correction link; determining the system bandwidth; determining two handover frequencies during the correction link; determining a low-frequency band during the correction link; determining a high-frequency band during the correction link; determining the convergence frequency band of the correction link; determining the transmission function during the correction link; determining the switching time; determine the switching step length; determining the velocity variable before and after the correction; acquiring acceleration and angular velocity of the inertial device output; compensating for the inertia device output according to the error source of the inertial device; integrating the acceleration information to obtain the speed; acquiring a velocity correction value; acquiring speed after the correction; acquiring angular velocity information after the correction and feeding back by the Shura loop; and integrating the speed after the correction to obtain the position after the correction. By the adoption of the method provided by the invention, overshoot errors generated during the state switching process can be inhibited without depending on the external speed.

Description

Boats and ships inertial navigation system autonomous type non-overshoot state switching method

Technical field

The present invention relates to the inertial navigation technology field, refer to a kind of boats and ships inertial navigation system autonomous type non-overshoot state switching method particularly.

Technical background

The horizontal circuit essence of inertial navigation system is the second-order system of a neutrality, and system is under error source (gyroscopic drift, accelerometer bias etc.) effect, and output demonstrates periodic swinging trend.In order to suppress the oscillatory error of system, a kind of effective solution adds correction link exactly in system circuit, changes the characteristic root of system circuit, makes the loop have damping action, with the oscillatory error that decays and cause owing to error source.Can know according to control theory, add after the correction link, make the inertial navigation system precision receive the carrier acceleration action strong, therefore when boats and ships are in maneuvering condition, need make inertial navigation system switch to no correcting state by correcting state.Therefore boats and ships can frequently be adjusted the duty of inertial navigation system based on the motion state of carrier in underway.When system did not have correcting state and switches to correcting state, system circuit was undergone mutation because of state after adding the damping link, and this can cause system when carrying out the switching of " nothing is corrected to corrections " state, to cause the overshoot error.With the system level correction is example; When the state that does not have the level correction of being corrected to switches; System will be in 1～2 shura (a shura cycle is 84.4 minutes) completion status transient process in the cycle; Therefore the overshoot error that in this section process, occurs will make that the output information of inertial navigation system is unavailable, influence the navigation safety of inertial navigation system precision and boats and ships greatly.

Correlative study (Cheng Jianhua, Zhao Lin, Song Juncai etc. automatic compensatory technique is in the research of Platform Inertial Navigation System state Application in Switching) explained the overshoot reasons of error from the angle of " transient equilibrium " at present, propose to utilize outer speed to carry out the overshoot compensation.But this compensation way depends on outer degree of testing the speed, and has and remain not compensating error, and this remains compensating error not all has considerable influence to the navigation safety of inertial navigation system precision and boats and ships.

Summary of the invention

The object of the invention will provide a kind of boats and ships inertial navigation system autonomous type non-overshoot state switching method exactly, and this method can be implemented under the situation that does not rely on extraneous speed, thoroughly suppresses to switch the overshoot error that produces in (nothing is corrected to correction) process because of state.

For realizing above-mentioned purpose, the present invention designs a kind of boats and ships inertial navigation system autonomous type non-overshoot state switching method, it is characterized in that it comprises the steps:

Step S 11: from suppressing the systematic error aspect and reducing influence two the aspects considerations of correction link to system circuit, confirm to be suitable for the dampingratio of Vessel's Description according to the ship motion state;

Step S12: confirm the time domain parameter of correction link, said time domain parameter comprises resonance peak M _rWith adjusting time t _s,

Relational expression according to second-order system resonance peak and damping ratio

$M_r=\frac{1}{2\mathrm{\ζ}\sqrt{1-{\mathrm{\ζ}}^2}}---\left(1\right)$

With the dampingratio substitution that obtains among the step S11 wherein, draw the resonance peak M of system _rSimultaneously, set the adjusting time t of trimming process _sBe set-point A;

Step S13: confirm the cutoff frequency of trimming process expectation,

Relational expression according to high order system frequency domain and time domain index

$t_s=\frac{\mathrm{K\π}}{{\mathrm{\ω}}_c}---\left(2\right)$

In the formula: K=2+1.5 (M _r-1) (M+2.5 _r-1) ², t _sFor regulating time set-point A among the step S12; M _rBe resonance peak M among the step S12 _r

Obtain the cutoff frequency ω of trimming process expectation _c

Step S14: the system bandwidth of confirming correction link;

According to the automatic control system theory, obtain the relational expression of system bandwidth and maximum Phase margin

$\frac{1}{\sin \mathrm{\γ}}=\frac{H+1}{H-1}---\left(3\right)$

In the formula: H is the system bandwidth of correction link, and γ is a Phase margin, and wherein, Phase margin γ is setting value B, Phase margin γ substitution formula (3) is obtained the value of the system bandwidth H of correction link;

Step S15: the two handing-over frequencies of confirming correction link;

Angular frequency according to maximum phase angle _mRelational expression

${\mathrm{\ω}}_m=\sqrt{{\mathrm{\ω}}_2{\mathrm{\ω}}_3}---\left(4\right)$

The system bandwidth relational expression of correction link

H＝ω ₂/ω ₃ (5)

In addition, obtain big as far as possible Phase margin, select the cutoff frequency of the maximum phase angle margin angle frequency of correction link, i.e. ω near system for making system _m≈ ω _c(6)

Can obtain two handing-over frequencies omega according to above-mentioned formula (4), formula (5), formula (6) ₂And ω ₃

Step S16: the low-frequency range of confirming correction link;

Proofreading and correct the back system adopts and the same low-frequency range of no corrective system;

Step S17: the high band of confirming correction link;

Proofreading and correct the back system adopts and the same high band of no corrective system;

Step S18: the linking frequency range of confirming correction link;

According to formula ω ₄=H * ω ₃(7)

In the formula: H is the system bandwidth of correction link, ω ₃Be the handing-over frequency among the step S15, obtain the linking frequency range ω of correction link according to formula (7) ₄

Step S19: according to S15, S18 confirms that the transport function of correction link is following formula

$G\left(s\right)=\frac{(1+s/{\mathrm{\ω}}_2)(1+s/{\mathrm{\ω}}_4)}{{(1+s/{\mathrm{\ω}}_3)}^2}---\left(8\right)$

Wherein s is a differentiating operator;

Step S20: when step S11 carries out, confirm that system does not transfer the transit time that correcting state switches to by the nothing correction, it is 10～20 minutes preset times that the transit time that transfers the correcting state switching to is proofreaied and correct by nothing by said system;

Step S21: according to the handing-over frequencies omega in the correction link transport function of confirming among the S19 ₂, ω ₃, be connected frequencies omega ₄And the handing-over frequencies omega of confirming system transit time of the switching of the state among the step S20 ₂, ω ₃, be connected frequencies omega ₄The switching step-length; The concrete step-length of switching is according to formula

Obtain, wherein, the correcting state parameter is the parameter of the transport function of definite suitable current motion state, the handing-over frequencies omega ₂, ω ₃With the linking frequencies omega ₄, current plan correcting state parameter is the parameter of the transport function of inertial navigation system before correction, the handing-over frequencies omega ₂, ω ₃With the linking frequencies omega ₄, switching the excessive time is 10～20 minutes.

Step S22: the speed differential equation before and after the transport function of utilizing correction link among the step S19 carries out can obtaining proofreading and correct after the anti-Laplace transform to the formula among the step S19 (8);

Speed before the definition boats and ships are proofreaied and correct is v, and the speed after the correction is v '.Formula (8) is a transport function between the two, is second order differential equation.For formula (8) is carried out conversion, defining two intermediate variables is u ₁, u ₂, have:

$u_1=\frac{({\mathrm{\ω}}_4-{\mathrm{\ω}}_3)v}{s+{\mathrm{\ω}}_3}$

(9)

$u_2=\frac{({\mathrm{\ω}}_2-{\mathrm{\ω}}_3)}{s+{\mathrm{\ω}}_3}(v+u_1)$

Formula (8) is carried out corresponding deformation, can obtain following differential equation group.

${\stackrel{\·}{u}}_1+{\mathrm{\ω}}_3{u}_1=\left({\mathrm{\ω}}_4-{\mathrm{\ω}}_3\right)v$

${\stackrel{\·}{u}}_2+{\mathrm{\ω}}_3{u}_2=\left({\mathrm{\ω}}_2-{\mathrm{\ω}}_3\right)v+({\mathrm{\ω}}_2-{\mathrm{\ω}}_3)u_1---\left(10\right)$

v′＝q(v+u ₁+u ₂)

is the constant in the equation conversion.Length velocity relation before and after above-mentioned system of equations has been confirmed to proofread and correct;

After obtaining the speed differential equation, switch step-length, ω during promptly each velocity correction according to the frequency parameter of confirming among the step S21 ₂, ω ₃, ω ₄The change amount, thereby the velocity variable before and after confirm proofreading and correct according to formula (10);

Step S31: obtain the angular velocity and the acceleration information of inertia device output, said inertia device is gyro and accelerometer;

Step S32: angular velocity and the acceleration information inertia device exported according to the error source of inertia device compensate;

Step S33: the acceleration information of accelerometer output is carried out integration obtain velocity information;

Step S34: according to the velocity variable before and after proofreading and correct among the step S22, and the speed before the correction among the step S33 obtains the velocity correction amount;

Step S35: obtain proofreading and correct back speed based on speed before proofreading and correct among the step S33 and the velocity correction amount among the step S34;

Step S36: utilize velocity information after the correction among the step S35, obtain proofreading and correct the back angular velocity information according to the inertial navigation system model, the navigation calculation of step S33～step S38 is carried out in this corrections afterwards angular velocity information to step S32 continued through the shura circuit feedback;

Step S37: speed after the correction among the step S35 is carried out integration;

Step S38: the positional information after obtaining proofreading and correct is promptly accomplished whole handoff procedure.

Ship motion state among the above-mentioned steps S11 is the frequency and the amplitude of speed, acceleration, oscillating motion.

Dampingratio among the above-mentioned steps S11 is 0～1.

Dampingratio among the above-mentioned steps S11 is 0.5.

The adjusting time t of trimming process among the above-mentioned steps S12 _sIt is 20～40 minutes.

Phase margin γ is 45～60 degree among the above-mentioned steps S14.

Phase margin γ is 45 degree among the above-mentioned steps S14.

The present invention is at first from the controlling models in inertial navigation system loop; The Phase margin, open loop amplitude-frequency rate of curve, cutoff frequency, corner frequency that indexs such as the rise time on the time domain specification, adjusting time are converted into response with bandwidth, be connected frequency domain indexs such as frequency range; The open loop amplitude versus frequency characte of drawing system expectation provides the method for designing of analytic expression of parameter, the structure of the corrective network of inertial navigation system.Make the corrective network compliance with system stability requirement of design through this method, the gain of high and low frequency section guarantees that system has noise inhibiting ability preferably, system's time domain index accord with expectation.Design the damping correction link with different damping ratio, when inertial navigation system carries out the state switching, thereby the parameter that continuously changes correction link changes the system damping ratio, reduces the overshoot error that causes because of the loop state sudden change.

State switching method provided by the invention is based on the controlling models in inertial navigation system loop; Realization does not rely on external information; The structure, parameter that only changes system compensation link transport function with and variation pattern; Realized that inertial navigation system switches at the steady non-overshoot that carries out " do not have and proofread and correct---proofread and correct " state, solved the disabled problem of information in the transient process that inertial navigation system switches, principal feature generally speaking of the present invention and advantage be following:

(1) overcomes traditional trial method and carried out the blindness of corrective network design and tentative.The design of inertial navigation system will be based on two cardinal rules: first will make the correction link of introducing have bigger damping ratio; To suppress the oscillatory error of system within a short period of time; Second correction link that will reduce to introduce is to the influence of system, and this requires system should have less damping ratio.Traditional corrective network method for designing is the damping link damping ratio of introducing to be set on 0.5 the basis, to carry out the trial of network parameter according to system's characteristics, utilizing the network of attempting to carry out system experimentation, according to experiment effect at further adjustment relevant parameter.This method designed system damping ratio relative fixed only is suitable for as under the very little situation of boats and ships acceleration.In addition, this method has very big exploratory, can not guarantee the corrective network optimization of parameters.Method of the present invention directly is converted into frequency-domain index with index on the time domain specification in inertial navigation system loop, the open loop amplitude versus frequency characte of drawing system expectation.This method can be resolved the parameters optimization and the structure that obtain correction link according to the damping ratio of system's expectation, has stronger specific aim and adaptability.

(2) suppress system and carried out the error that " not having correction-correction " state switches.Classic method is when switching, and return transfer function is undergone mutation, and system changes progressive steady state (SS) into by neutrality, and the overshoot error appears in the system that makes in state conversion process.This error even surpassed the error of system at no timing causes inertial navigation system output information unavailable in stateful switchover process, has influenced the continuity of inertial navigation system, and threatens the navigation safety on naval vessel.The present invention proposes in the inertial system state handoff procedure, and the parameter of continuous change correction link makes system not proofread and correct the corrective network of progressive smooth transition to the expectation damping ratio by having.Because the progressive change of system state, system's transient process is steady, the non-overshoot error, and system output information is available continuously.After system got into correcting state, the oscillatory error obtained decay.

(3) oracle be need not rely on, autonomous, full remuneration that system state is switched realized.Turntable provided by the invention switches the overshoot method based on modeling and analysis to the inertial navigation system loop; Correction link through reasonable change and design system; Utilize system's self information to realize that the non-overshoot of inertial navigation duty switches, thoroughly the overshoot error of bucking-out system.

Description of drawings

Fig. 1 is a schematic diagram of the present invention;

Fig. 2 is the contrast test checking result of state switching method of the present invention and classic method.

Embodiment

Below in conjunction with accompanying drawing and specific embodiment the present invention is made further detailed description:

Like the described a kind of boats and ships inertial navigation system autonomous type non-overshoot state switching method of Fig. 1, it is characterized in that it comprises the steps:

Step S11: from suppressing the systematic error aspect and reducing correction link two aspects that influence of system circuit are considered according to ship motion state (frequency of speed, acceleration, oscillating motion, amplitude); Confirm to be suitable for the dampingratio of Vessel's Description; Dampingratio is 0～1, is preferably 0.5;

Step S12: confirm the time domain parameter of correction link, said time domain parameter comprises resonance peak M _rWith adjusting time t _s,

Relational expression according to second-order system resonance peak and damping ratio

$M_r=\frac{1}{2\mathrm{\ζ}\sqrt{1-{\mathrm{\ζ}}^2}}---\left(1\right)$

With the dampingratio substitution that obtains among the step S11 wherein, draw the resonance peak M of system _rSimultaneously, set the adjusting time t of trimming process _sIt is 20～40 minutes;

Among the step S12, when the correction link of expectation has ζ=0.5 damping ratio, for example is carried out the correction link design that system state is switched.This moment system resonance peak M _r=1.1547.System produces the continuous oscillation in shura cycle under the constant error effect, the rise time of response was 1/4 shura cycle.Be acquisition better dynamic performance, but the adjusting time of initialization system is 0.5 shura cycle, promptly regulates time t _s=2532s

Step S13: confirm the cutoff frequency of trimming process expectation,

Relational expression according to high order system frequency domain and time domain index

$t_s=\frac{\mathrm{K\π}}{{\mathrm{\ω}}_c}---\left(2\right)$

In the formula: K=2+1.5 (M _r-1) (M+2.5 _r-1) ², t _sFor regulating time t among the step S12 _s=2532s; M _rBe resonance peak M among the step S12 _r=1.1547;

Obtain the cutoff frequency ω of trimming process expectation _c=0.0028rad/s;

Step S 14: the system bandwidth of confirming correction link;

According to the automatic control system theory, obtain the relational expression of system bandwidth and maximum Phase margin

$\frac{1}{\sin \mathrm{\γ}}=\frac{H+1}{H-1}---\left(3\right)$

In the formula: H is the system bandwidth of correction link, and γ is a Phase margin, and wherein, Phase margin γ is 45～60 degree, is preferably 45 degree, Phase margin γ substitution formula (3) is obtained the value H=13.9282 of the system bandwidth H of correction link;

Step S15: the two handing-over frequencies of confirming correction link;

Angular frequency according to maximum phase angle _mRelational expression

${\mathrm{\ω}}_m=\sqrt{{\mathrm{\ω}}_2{\mathrm{\ω}}_3}---\left(4\right)$

The system bandwidth relational expression of correction link

H＝ω ₂/ω ₃ (5)

In addition, obtain big as far as possible Phase margin, select the cutoff frequency of the maximum phase angle margin angle frequency of correction link, i.e. ω near system for making system _m≈ ω _c(6)

Can obtain two handing-over frequencies omega according to above-mentioned formula (4), formula (5), formula (6) ₂And ω ₃Can get two handing-over frequencies omega according to above formula ₂=7.5025 * 10 ^-4Rad/s, ω ₃=1.04 * 10 ^-2Rad/s

Step S16: the low-frequency range of confirming correction link;

Proofreading and correct the back system adopts and the same low-frequency range of no corrective system;

Step S17: the high band of confirming correction link;

Proofreading and correct the back system adopts and the same high band of no corrective system;

Step S18: the linking frequency range of confirming correction link;

According to formula ω ₄=H * ω ₃(7)

In the formula: H is the system bandwidth of correction link, ω ₃Be the handing-over frequency among the step S15, obtain the linking frequency range ω of correction link according to formula (7) ₄, can get ω according to above formula ₄=H * ω ₃=0.1449.

Step S19: according to S15, S18 confirms that the transport function of correction link is following formula (8)

$G\left(s\right)=\frac{(1+s/{\mathrm{\ω}}_2)(1+s/{\mathrm{\ω}}_4)}{{(1+s/{\mathrm{\ω}}_3)}^2}---\left(8\right)$

Above each corner frequency substitution is got:

$G\left(s\right)=\frac{(1+7.5025\×{10}^{-4})(s+0.1449)}{{(s+1.04\×{10}^{-2})}^2}$

Step S20: when step S11 carries out, confirm that system does not transfer the transit time that correcting state switches to by the nothing correction, it is 10～20 minutes that the transit time that transfers the correcting state switching to is proofreaied and correct by nothing by said system;

Step S21: according to the handing-over frequencies omega in the correction link transport function of confirming among the S 19 ₂, ω ₃, be connected frequencies omega ₄And the state among the step S20 switch 10～20 minutes transit times definite system the handing-over frequencies omega ₂, ω ₃, be connected frequencies omega ₄The switching step-length; The concrete step-length of switching is according to formula

Obtain, wherein, the correcting state parameter is the parameter of the transport function of definite suitable current motion state, the handing-over frequencies omega ₂, _{ω 3}With the linking frequencies omega ₄, current plan correcting state parameter is the parameter of the transport function of inertial navigation system before correction, the handing-over frequencies omega ₂, ω ₃With the linking frequencies omega ₄, switching the excessive time is 10～20 minutes.

Step S22: the speed differential equation before and after the transport function of utilizing correction link among the step S 19 carries out can obtaining proofreading and correct after the anti-Laplace transform to the formula among the step S 19 (8);

Speed before the definition boats and ships are proofreaied and correct is v, and the speed after the correction is v '.Formula (8) is a transport function between the two, is second order differential equation.For formula (8) is carried out conversion, defining two intermediate variables is u ₁, u ₂, have:

${\mathrm{<figure-callout\; id="1"\; label="u"\; filenames="HDA0000089760830000021.png"\; state="\{\{state\}\}">u</figure-callout>}}_1=\frac{({\mathrm{\&omega;}}_4-{\mathrm{\&omega;}}_3)v}{s+{\mathrm{\&omega;}}_3}$

(9)

$u_2=\frac{({\mathrm{\&omega;}}_2-{\mathrm{\&omega;}}_3)}{s+{\mathrm{\&omega;}}_3}(v+u_1)$

Formula (8) is carried out corresponding deformation, can obtain following differential equation group.

${\stackrel{\&CenterDot;}{u}}_1+{\mathrm{\&omega;}}_3{\mathrm{<figure-callout\; id="1"\; label="u"\; filenames="HDA0000089760830000021.png"\; state="\{\{state\}\}">u</figure-callout>}}_1=\left({\mathrm{\&omega;}}_4-{\mathrm{\&omega;}}_3\right)v$

${\stackrel{\&CenterDot;}{u}}_2+{\mathrm{\&omega;}}_3{u}_2=\left({\mathrm{\&omega;}}_2-{\mathrm{\&omega;}}_3\right)v+({\mathrm{\&omega;}}_2-{\mathrm{\&omega;}}_3)u_1---\left(10\right)$

v′＝q(v+u ₁+u ₂)

is the constant in the equation conversion.Length velocity relation before and after above-mentioned system of equations has been confirmed to proofread and correct, wherein,

With Be respectively intermediate variable u ₁And u ₂Differential;

After obtaining the speed differential equation, switch step-length, ω during promptly each velocity correction according to the frequency parameter of confirming among the step S21 ₂, ω ₃, ω ₄The change amount, thereby the velocity variable before and after confirm proofreading and correct according to formula (10);

Step S31: obtain the angular velocity and the acceleration information of inertia device output, said inertia device is gyro and accelerometer;

Step S32: angular velocity and the acceleration information inertia device exported according to the error source of inertia device compensate; Wherein, the error source of inertia device is an inherent error in the existing inertia system, the compensation of step S32 for this inherent error is carried out, and it is for well known to a person skilled in the art prior art;

Step S33: the acceleration information of accelerometer output is carried out integration obtain velocity information;

Step S34: according to the velocity variable before and after proofreading and correct among the step S22, and the speed before the correction among the step S33 obtains the velocity correction amount;

Step S35: obtain proofreading and correct back speed based on speed before proofreading and correct among the step S33 and the velocity correction amount among the step S34;

Step S36: utilize the velocity information after proofreading and correct among the step S35, obtain proofreading and correct the back angular velocity information according to the inertial navigation system model, this correction back angular velocity information carries out the navigation calculation of step S33～step S38 to step S32 continued through the shura circuit feedback;

Step S37: speed after the correction among the step S35 is carried out integration;

Step S38: the positional information after obtaining proofreading and correct is promptly accomplished whole handoff procedure.

The process that draws of formula (3) is among the step S 14 of technique scheme:

In order to make system under same bandwidth condition, have better stability margin, the neutrality system is after overcorrect, and Mid Frequency should have the transport function of following form:

$G\left(s\right)=\frac{{\mathrm{\&omega;}}_s^2(1+s/{\mathrm{\&omega;}}_2)}{s^2(1+s/{\mathrm{\&omega;}}_3)}---\left(9\right)$

In the formula: ω ₂Be the corner frequency before the cutoff frequency, make system's amplitude versus frequency characte increase 20dB/dec slope, ω ₃Be the corner frequency behind the cutoff frequency, choose reasonable ω ₃Can confirm system bandwidth.

The phase angle γ (ω) of transport function is in the formula (9):

$\mathrm{\&gamma;}\left(\mathrm{\&omega;}\right)=\mathrm{acrtg}\frac{\mathrm{\&omega;}}{{\mathrm{\&omega;}}_2}-\mathrm{acrtg}\frac{\mathrm{\&omega;}}{{\mathrm{\&omega;}}_3}---\left(10\right)$

The angular frequency of the maximum phase angle of formula (10) generation system _mFor:

${\mathrm{\&omega;}}_m=\sqrt{{\mathrm{\&omega;}}_2{\mathrm{\&omega;}}_3}---\left(11\right)$

Formula (11) substitution formula (10) is got

$\sin \mathrm{\&gamma;}\left(\mathrm{\&omega;}\right)=\frac{{\mathrm{\&omega;}}_3-{\mathrm{\&omega;}}_2}{{\mathrm{\&omega;}}_3+{\mathrm{\&omega;}}_2}---\left(12\right)$

According to definitions of bandwidth, intermediate-frequency bandwidth H=ω ₂/ ω ₃, its substitution formula (12) is got:

$\frac{1}{\sin \mathrm{\&gamma;}\left({\mathrm{\&omega;}}_m\right)}=\frac{H+1}{H-1}---\left(12\right)$

For making system obtain big as far as possible Phase margin, select the cutoff frequency of the maximum phase angle margin angle frequency of correction link near system, can think ω _m≈ ω _c, can get by formula (12): $\frac{1}{\mathrm{Sin}\mathrm{\&gamma;}}=\frac{H+1}{H-1}.$

Concrete effect of the present invention is by shown in Figure 2.

The content that this instructions is not done to describe in detail belongs to this area professional and technical personnel's known prior art.

Claims (7)

1. a boats and ships inertial navigation system autonomous type non-overshoot state switching method is characterized in that it comprises the steps:

Step S11: from suppressing the systematic error aspect and reducing influence two the aspects considerations of correction link, confirm to be suitable for the dampingratio of Vessel's Description to system circuit according to the ship motion state;

Step S12: confirm the time domain parameter of correction link, said time domain parameter comprises resonance peak M _rWith adjusting time t _s,

Relational expression according to second-order system resonance peak and damping ratio

With the dampingratio substitution that obtains among the step S11 wherein, draw the resonance peak M of system _rSimultaneously, set the adjusting time t of trimming process _sBe set-point A;

Step S13: confirm the cutoff frequency of trimming process expectation,

Relational expression according to high order system frequency domain and time domain index

In the formula: K=2+1.5 (M _r-1) (M+2.5 _r-1) ², t _sFor regulating time set-point A among the step S 12; M _rBe resonance peak M among the step S12 _r

Obtain the cutoff frequency ω of trimming process expectation _c

Step S14: the system bandwidth of confirming correction link;

According to the automatic control system theory, obtain the relational expression of system bandwidth and maximum Phase margin

In the formula: H is the system bandwidth of correction link, and γ is a Phase margin, and wherein, Phase margin γ is setting value B, Phase margin γ substitution formula (3) is obtained the value of the system bandwidth H of correction link;

Step S15: the two handing-over frequencies of confirming correction link;

Angular frequency according to maximum phase angle _mRelational expression

The system bandwidth relational expression of correction link

H＝ω ₂/ω ₃ (5)

In addition, obtain big as far as possible Phase margin, select the cutoff frequency of the maximum phase angle margin angle frequency of correction link, i.e. ω near system for making system _m≈ ω _c(6)

Can obtain two handing-over frequencies omega according to above-mentioned formula (4), formula (5), formula (6) ₂And ω ₃

Step S16: the low-frequency range of confirming correction link;

Proofreading and correct the back system adopts and the same low-frequency range of no corrective system;

Step S17: the high band of confirming correction link;

Proofreading and correct the back system adopts and the same high band of no corrective system;

Step S18: the linking frequency range of confirming correction link;

According to formula ω ₄=H * ω ₃(7)

In the formula: H is the system bandwidth of correction link, ω ₃Be the handing-over frequency among the step S15, obtain the linking frequency range ω of correction link according to formula (7) ₄

Step S19: according to S15, S18 confirms that the transport function of correction link is following formula

Wherein s is a differentiating operator;

Step S20: when step S11 carries out, confirm that system does not transfer the transit time that correcting state switches to by the nothing correction, it is 10～20 minutes preset times that the transit time that transfers the correcting state switching to is proofreaied and correct by nothing by said system;

Step S21: according to the handing-over frequencies omega in the correction link transport function of confirming among the S19 ₂, ω ₃, be connected frequencies omega ₄And the handing-over frequencies omega of confirming system transit time of the switching of the state among the step S20 ₂, ω ₃, be connected frequencies omega ₄The switching step-length; The concrete step-length of switching is according to formula

Obtain, wherein, the correcting state parameter is the parameter of the transport function of definite suitable current motion state, the handing-over frequencies omega ₂, ω ₃With the linking frequencies omega ₄, current plan correcting state parameter is the parameter of the transport function of inertial navigation system before correction, the handing-over frequencies omega ₂, ω ₃With the linking frequencies omega ₄, switching the excessive time is 10～20 minutes.

Step S22: the speed differential equation before and after the transport function of utilizing correction link among the step S19 carries out can obtaining proofreading and correct after the anti-Laplace transform to the formula among the step S19 (8);

Speed before the definition boats and ships are proofreaied and correct is v, and the speed after the correction is v ', and formula (8) is a transport function between the two, is second order differential equation.For formula (8) is carried out conversion, defining two intermediate variables is u ₁, u ₂, have:

(9)

Formula (8) is carried out corresponding deformation, can obtain following differential equation group.

v′＝q(v+u ₁+u ₂)

is the constant in the equation conversion.Length velocity relation before and after above-mentioned system of equations has been confirmed to proofread and correct;

After obtaining the speed differential equation, switch step-length, ω during promptly each velocity correction according to the frequency parameter of confirming among the step S21 ₂, ω ₃, ω ₄The change amount, thereby the velocity variable before and after confirm proofreading and correct according to formula (10);

Step S31: obtain the angular velocity and the acceleration information of inertia device output, said inertia device is gyro and accelerometer;

Step S32: angular velocity and the acceleration information inertia device exported according to the error source of inertia device compensate;

Step S33: the acceleration information of accelerometer output is carried out integration obtain velocity information;

Step S34: according to the velocity variable before and after proofreading and correct among the step S22, and the speed before the correction among the step S33 obtains the velocity correction amount;

Step S35: obtain proofreading and correct back speed based on speed before proofreading and correct among the step S33 and the velocity correction amount among the step S34;

Step S36: utilize velocity information after the correction among the step S35, obtain proofreading and correct the back angular velocity information according to the inertial navigation system model, the navigation calculation of step S33～step S38 is carried out in this corrections afterwards angular velocity information to step S32 continued through the shura circuit feedback;

Step S37: speed after the correction among the step S35 is carried out integration;

Step S38: the positional information after obtaining proofreading and correct is promptly accomplished whole handoff procedure.

2. boats and ships inertial navigation system autonomous type non-overshoot state switching method according to claim 1, it is characterized in that: the ship motion state among the step S11 is speed, acceleration, oscillating motion frequency and amplitude.

3. boats and ships inertial navigation system autonomous type non-overshoot state switching method according to claim 1, it is characterized in that: the dampingratio among the step S11 is 0～1.

4. boats and ships inertial navigation system autonomous type non-overshoot state switching method according to claim 3, it is characterized in that: the dampingratio among the step S11 is 0.5.

5. boats and ships inertial navigation system autonomous type non-overshoot state switching method according to claim 1 is characterized in that: the adjusting time t of trimming process among the step S12 _sIt is 20～40 minutes.

6. boats and ships inertial navigation system autonomous type non-overshoot state switching method according to claim 1 is characterized in that: Phase margin γ is 45～60 degree among the step S14.

7. boats and ships inertial navigation system autonomous type non-overshoot state switching method according to claim 6 is characterized in that: Phase margin γ is 45 degree among the step S14.

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