CN100567895C - Low accuracy piezoelectric gyroscope zero-bias real-time estimation compensation process - Google Patents

Abstract

The invention discloses a kind of low accuracy piezoelectric gyroscope zero-bias real-time compensation method, information acquisition unit (2) is to the angular velocity information ω of low accuracy piezoelectric gyroscope (1) output ₀Gather with analog-to-digital conversion process after output digital angular velocity information ω ₁The digital angular velocity information ω of angular velocity denoising Processing unit (3) to receiving ₁Adopt Tom pine singular value elimination method to carry out open country point and reject the wild point of acquisition nothing angular velocity information, carry out the noise reduction smoothing processing to there being wild five smoothing methods of angular velocity information employing of putting then, obtain noise reduction angular velocity information ω ₂The noise reduction angular velocity information ω of angular rate compensation unit (4) to receiving ₂Adopt the mode that combines with carrier rectilinear motion state to carry out zero real-time partially estimation and compensation, the angular velocity information ω after obtaining to compensate ₃

Description

Low accuracy piezoelectric gyroscope zero-bias real-time estimation compensation process

Technical field

The present invention relates to a kind of to low precision (be meant angular velocity zero partially drift be 0.1～2.0 °/s) piezoelectric gyroscope zero-bias carries out the method for real-time estimation compensation.

Background technology

Boat appearance information is navigational parameter important in the carrier movement process, can mate by earth magnetism, satellite navigation, multiple means such as radio navigation are determined the locus of carrier, but in all at present navigate modes, have inertial navigation only and have stronger independence, round-the-clock and antijamming capability, therefore inertial navigation is the main flow of airmanship development, in inertial navigation, the measuring accuracy of gyro is the key factor that influences the inertial navigation system precision, the gyro of lower accuracy can't guarantee the boat appearance precision of inertial navigation system, and the measuring accuracy that therefore improves gyro is imperative.The method that solves generally has: 1) improve the gyro performance from hardware aspects such as technological design and materials processings, improve the gyro index, but the method is subjected to the restriction of each side development such as technology and material science, precision improves limited and cost is higher, construction cycle is longer, can not practical requirement; 2) from the software program aspect to gyro carry out zero partially, parameter such as drift is estimated and compensate, can improve the precision of gyro preferably, then cost is reduced, and the construction cycle lack, can adjust correlation parameter in real time according to request for utilization preferably.

At present, being controlled at the software program aspect for the precision of gyro is to set up the error model of gyro according to the composition mechanism of gyro, thereby set up the Kalman filter equation relevant with the gyro performance parameter, utilizing effective observation information that zero of gyro is drifted about partially estimates and compensation, the method is only applicable to high accuracy gyroscope, but for the gyro of the low precision of low cost: then have 1) the measurement noise randomness of gyro is stronger, do not satisfy the precondition of Markov process and Gauss's self noise, be difficult to gyro is set up the linear model that meets Kalman filter equation; 2) uncertainty of gyro to measure noise causes Kalman filter to be dispersed easily in the carrier movement process, is difficult to reach by software program compensate the purpose that improves Gyro Precision.

Summary of the invention

Bigger in order to solve existing low accuracy piezoelectric gyroscope zero-bias, the bigger problem of boat appearance systematic error that noise causes more greatly, the present invention proposes a kind of zero-bias real-time estimation compensation process that is applicable to low accuracy piezoelectric gyroscope, utilized the output angle speed average of gyro in carrier rectilinear motion process near 0 °/s, and with the zero stable partially principle of gyro output angle speed in the 10s, and the output angle velocity information is carried out zero of gyro and is estimated partially in real time and compensation during in conjunction with the motion state of carrier and gyro running status, thereby reaches the precision of raising low accuracy piezoelectric gyroscope output angle velocity information.

The present invention is a kind of low accuracy piezoelectric gyroscope zero-bias real-time compensation method, and this method includes: information acquisition unit 2, angular velocity denoising Processing unit 3, angular rate compensation unit 4.

The angular velocity information ω of 2 pairs of low accuracy piezoelectric gyroscopes of information acquisition unit, 1 output ₀Gather with analog-to-digital conversion process after output digital angular velocity information ω ₁

The digital angular velocity information ω of the 3 pairs of receptions in angular velocity denoising Processing unit ₁Adopt Tom pine singular value elimination method to carry out open country point and reject the wild point of acquisition nothing angular velocity information, carry out the noise reduction smoothing processing to there being wild five smoothing methods of angular velocity information employing of putting then, obtain noise reduction angular velocity information ω ₂, and this information exported to angular rate compensation unit 4;

The noise reduction angular velocity information ω of the 4 pairs of receptions in angular rate compensation unit ₂The angular velocity of exporting down with carrier rectilinear motion state carries out zero real-time partially estimation and compensates, the angular velocity information ω after obtaining to compensate ₃, this information is the gyro angular velocity output behind the zero offset compensation.In the present invention, carrier under the rectilinear motion state, angular velocity information ω after the compensation of angular rate compensation unit 4 outputs this moment ₃Absolute value is 0.01～0.05 °/s.

The advantage of zero-bias real-time estimation compensation process of the present invention: only carry out the judgement of motion state in (1) carrier movement process, improved the independence of low accuracy piezoelectric gyroscope effectively by the angular velocity information behind the low accuracy piezoelectric gyroscope self-compensation situation; In compensation process, need not other utility appliance, reduced boat appearance system cost; (2) zero adopt three piecewise analysis methods (promptly judging layer, decision-making level, application layer) in the estimation procedure partially, improved low accuracy piezoelectric gyroscope and estimated zero inclined to one side reliability; (3) zero real-time partially estimation compensation according to the rectilinear motion state of carrier and piezolectric gyroscope de-noising after angular velocity information in the streamlined process, obtain the partially zero of low accuracy piezoelectric gyroscope, under the condition that need not set up gyroscope error model, reduced calculated amount, improve the travelling speed of system effectively, reduced testing cost; (4) adopt open program code, made things convenient for system debug, reduced taking of processor memory space; (5) the angular velocity information precision of low accuracy piezoelectric gyroscope output can be improved an order of magnitude by the gyro zero offset compensation method that combines with the carrier movement state, promptly gyro zero drifts about partially and is reduced to 0～0.05 °/s by 0.1～2.0 ° original/s.

Description of drawings

Fig. 1 is the structured flowchart of the real-time estimation compensation of low accuracy piezoelectric gyroscope zero-bias of the present invention.

Fig. 2 is the real-time estimation compensation process flow diagram of low accuracy piezoelectric gyroscope zero-bias of the present invention.

Fig. 3 is the correlation curve figure that adopts gyro zero offset compensation of the present invention front and back.

Embodiment

The present invention is described in further detail below in conjunction with drawings and Examples.

In the present invention, the angular velocity zero inclined to one side drift for the output of piezoelectric type gyro is the low accuracy piezoelectric gyroscope that is called of 0.1～2.0 °/s.

The present invention is a kind of low accuracy piezoelectric gyroscope zero-bias real-time compensation method, and this method includes: information acquisition unit 2, angular velocity denoising Processing unit 3, angular rate compensation unit 4, and referring to shown in Figure 1.

The angular velocity information ω of 2 pairs of low accuracy piezoelectric gyroscopes of information acquisition unit, 1 output ₀Gather with analog-to-digital conversion process after output digital angular velocity information ω ₁

The digital angular velocity information ω of the 3 pairs of receptions in angular velocity denoising Processing unit ₁Adopt Tom pine singular value elimination method to carry out open country point and reject the wild point of acquisition nothing angular velocity information, carry out the noise reduction smoothing processing to there being wild five smoothing methods of angular velocity information employing of putting then, obtain noise reduction angular velocity information ω ₂, and this information exported to angular rate compensation unit 4;

The noise reduction angular velocity information ω of the 4 pairs of receptions in angular rate compensation unit ₂The angular velocity of exporting down with carrier rectilinear motion state carries out zero real-time partially estimation and compensates, the angular velocity information ω after obtaining to compensate ₃, this information is the gyro angular velocity output behind the zero offset compensation.In the present invention, carrier under the rectilinear motion state, angular velocity information ω after the compensation of angular rate compensation unit 4 outputs this moment ₃Absolute value is 0.01～0.05 °/s.

Include the single sampled point x of mean value x, N angular velocity sampled point of number N, N angular velocity sampled point of angular velocity sampled point in described Tom pine singular value elimination method _i, current time k sampled point x _k, a N angular velocity sampled point variance S ², current time k angular velocity rejects threshold value t ' with respect to the departure degree τ of N angular velocity sampled point mean value x and the wild point of angular velocity.The mean value of described N angular velocity sampled point $\stackrel{\‾}{x}=\frac{1}{N}\underset{i=1}{\overset{N}{\mathrm{\Σ}}}{x}_i,$ The variance of described N angular velocity sampled point $S^{}$ ${}^2=\frac{1}{N}\underset{i=1}{\overset{N}{\mathrm{\Σ}}}{(x_i-\stackrel{\‾}{x})}^2,$ Described departure degree $\mathrm{\τ}=\frac{x_k-\stackrel{\‾}{x}}{S},$ The wild point of described angular velocity is rejected threshold value $t^{\′}=\frac{\mathrm{\τ}\sqrt{N-2}}{\sqrt{N-1-}{\mathrm{\τ}}^2}.$

Described 5 are once smoothly satisfied the second relational expression H, second relational expression $H=\frac{1}{5}(Y_{k-2}+Y_{k-1}+Y_k+Y_{k+1}+Y_{k+2}),$ In the formula, k represents current time, and Y is illustrated in continuous five sampled points that current time k is symmetrically distributed.

Zero offset compensation amount Δ ω adopts three piecewise analysis methods to carry out gyro output compensation in the described angular rate compensation unit 4.Three piecewise analysis are meant judges layer, analysis layer, application layer; Wherein, judge that layer is the zero offset compensation amount Δ ω that current time k is obtained _kFind the solution with data and preserve; Analysis layer is to judging the zero offset compensation amount Δ ω in the layer _kCompare with threshold epsilon, obtain to characterize the zero offset compensation amount Δ ω of carrier rectilinear motion state; Application layer is zero offset compensation and the output tracking that the zero offset compensation amount Δ ω in the employing analysis layer carries out gyro.The value of described threshold epsilon is to decide according to the variable quantity of the output angle speed of low accuracy piezoelectric gyroscope 1 under static condition, and then the span of threshold epsilon is 0.1～0.3 °/s.

In the present invention, the angular velocity of output is 0 °/s under the carrier rectilinear motion state.

Referring to shown in Figure 2, zero real-time partially estimation compensation of low accuracy piezoelectric gyroscope of the present invention includes following treatment step:

The first step: the angular velocity information ω that gathers the output of current time k low accuracy piezoelectric gyroscope by data acquisition unit 2 ₀

Second step: the angular velocity information ω that in data de-noising unit 3, collection is obtained ₁Utilize Tom pine (Thompson) singular value elimination method to limit threshold method filtering denoising Processing, utilize five smoothing methods to carry out level and smooth denoising Processing then, thereby obtain not have wild point and the level and smooth preceding angular velocity information ω of compensation ₂

The 3rd step: the zero offset compensation amount Δ ω that in compensating module, utilizes previous moment k-1 _K-1, the angular velocity numerical information ω of current time k piezolectric gyroscope output ₁, judge whether the motion state of current time k carrier is the rectilinear motion state;

The 4th step: utilize the compensation anterior angle speed numerical information ω in second step ₁The gyro angular velocity information that rectilinear motion state in the third step carries out in the time period T is preserved, be designated as the straight line data layout, the gyro angular velocity in the time period T and be designated as ω ' _Sum, ask the average ω ' of gyro in this section period _Sum/ T is gyro zero offset compensation amount Δ ω _k

The 5th step: to gyro compensation rate Δ ω _kThe three piecewise analysis methods of carrying out are judged; So-called three piecewise analysis methods are promptly: the current zero offset compensation amount Δ ω that tries to achieve _kFor judging layer, with compensation rate in the analysis layer and threshold epsilon more whether in certain threshold range, if in certain threshold range then think that this judgement layer is correct, the zero offset compensation amount can be passed to application layer, if not in certain threshold range, then abandon this judged result;

The 6th step: the zero offset compensation amount Δ ω that utilizes application layer to estimate carries out zero offset compensation, i.e. ω to gyro ₃=ω ₂-Δ ω;

The 7th step: the gyro information ω behind the preservation zero offset compensation ₃Go forward side by side the resolving of line correlation.

Embodiment

See also shown in Figure 3, when carrier flies at high-altitude 1000m, speed 300km/h before the compensation of low accuracy piezoelectric gyroscope output angular velocity (or claiming rudimentary horn speed) be curve I, among the figure as can be seen the zero of gyro be 1.0～1.5 °/s partially.Use compensation method of the present invention, angular velocity is curve II after the compensation of gyro output, zero of gyro is 0 °/s partially substantially as can be seen among the figure.The present invention can improve an order of magnitude with the angular velocity information precision of low accuracy piezoelectric gyroscope output by the gyro zero offset compensation method that combines with the carrier movement state.

The present invention proposes a kind of zero-bias real-time estimation compensation process that is applicable to low accuracy piezoelectric gyroscope, utilized the output angle speed average of gyro in carrier rectilinear motion process near 0 °/s, and with the zero stable partially principle of gyro output angle speed in the 10s, and the output angle velocity information is carried out zero of gyro and is estimated partially in real time and compensation during in conjunction with the motion state of carrier and gyro running status, thereby reaches the precision of raising low accuracy piezoelectric gyroscope output angle velocity information.Solve the bigger problem of boat appearance systematic error that existing low accuracy piezoelectric gyroscope zero-bias is big, noise causes more greatly.

Claims (4)

1, a kind of low accuracy piezoelectric gyroscope zero-bias real-time compensation method is characterized in that: information acquisition unit (2) is to the angular velocity information ω of low accuracy piezoelectric gyroscope (1) output ₀Gather with analog-to-digital conversion process after output digital angular velocity information ω ₁The digital angular velocity information ω of angular velocity denoising Processing unit (3) to receiving ₁Adopt Tom pine singular value elimination method to carry out open country point and reject the wild point of acquisition nothing angular velocity information, carry out the noise reduction smoothing processing to there being wild five smoothing methods of angular velocity information employing of putting then, obtain noise reduction angular velocity information ω ₂The noise reduction angular velocity information ω of angular rate compensation unit (4) to receiving ₂Employing combines with carrier rectilinear motion state and carries out zero real-time partially estimation and compensate, the angular velocity information ω after obtaining to compensate ₃, this angular velocity information ω ₃The concrete steps of obtaining are:

Utilize the zero offset compensation amount Δ ω of previous moment k-1 _K-1, the angular velocity numerical information ω of current time k ₁, judge whether the motion state of current time k carrier is the rectilinear motion state;

Utilize angular velocity numerical information ω ₁The gyro angular velocity information that the rectilinear motion state carries out in the time period T is preserved, be designated as the straight line data layout, the gyro angular velocity in the time period T and be designated as ω ' _Sum, ask the average ω ' of gyro in this section period _Sum/ T is gyro zero offset compensation amount Δ ω _k

To gyro compensation rate Δ ω _kThe three piecewise analysis methods of carrying out are judged; So-called three piecewise analysis methods are promptly: the current zero offset compensation amount Δ ω that tries to achieve _kFor judging layer, with compensation rate in the analysis layer and threshold epsilon more whether in certain threshold range, if in certain threshold range then think that this judgement layer is correct, the zero offset compensation amount can be passed to application layer, if not in certain threshold range, then abandon this judged result;

The zero offset compensation amount Δ ω that utilizes application layer to estimate carries out zero offset compensation ω to gyro ₃=ω ₂-Δ ω;

Gyro information ω behind the preservation zero offset compensation ₃Go forward side by side the resolving of line correlation.

2, low accuracy piezoelectric gyroscope zero-bias real-time compensation method according to claim 1 is characterized in that: the single sampled point x of mean value x, N angular velocity sampled point that includes number N, N angular velocity sampled point of angular velocity sampled point in described Tom pine singular value elimination method _i, current time k sampled point x _k, a N angular velocity sampled point variance S ², current time k angular velocity rejects threshold value t ' with respect to the departure degree τ of N angular velocity sampled point mean value x and the wild point of angular velocity;

Described mean value $\stackrel{\‾}{x}=\frac{1}{N}\underset{i=1}{\overset{N}{\mathrm{\Σ}}}{x}_i,$ Described variance $S^2=\frac{1}{N}\underset{i=1}{\overset{N}{\mathrm{\Σ}}}{(x_i-\stackrel{\‾}{x})}^2,$ Described departure degree $\mathrm{\τ}=\frac{x_k-\stackrel{\‾}{x}}{S},$ The wild point of described angular velocity is rejected threshold value $t^{\′}=\frac{\mathrm{\τ}\sqrt{N-2}}{\sqrt{N-1-{\mathrm{\τ}}^2}}.$

3, low accuracy piezoelectric gyroscope zero-bias real-time compensation method according to claim 1 is characterized in that: described 5 are once smoothly satisfied the second relational expression H, described second relational expression $H=\frac{1}{5}(Y_{k-2}+Y_{k-1}+Y_k+Y_{k+1}+Y_{k+2}),$ In the formula, k represents current time, and Y is illustrated in continuous five sampled points that current time k is symmetrically distributed.

4, low accuracy piezoelectric gyroscope zero-bias real-time compensation method according to claim 1 is characterized in that: angular velocity information ω after the compensation of described angular rate compensation unit (4) output ₃Absolute value is 0.01～0.05 °/s.

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