CN101561292A - Method and device for calibrating size effect error of accelerometer - Google Patents

Abstract

The invention provides a method and a device for calibrating a size effect error of an accelerometer. The method comprises the following steps: firstly preheating a strapdown inertial navigation system, and acquiring output data of a gyroscope and the accelerometer in the system; then calibrating the gyroscope, and compensating an gyro error; then rotating the system at different angular velocities, and acquiring a system horizontal velocity error when the system reaches the same position; and acquiring the size effect error of the accelerometer according to the change of the system horizontal velocity error. The method and the device can achieve system-level precise calibration of the size effect error of the accelerometer so as to furthest separate the size effect error of the accelerometer from other error items of the accelerometer and improve the navigation precision and efficiency of the system.

Description

A kind of scaling method of size effect error of accelerometer and device

Technical field

The present invention relates to field of navigation technology, relate in particular to a kind of scaling method and device of size effect error of accelerometer.

Background technology

At present, in field of navigation technology, inertial navigation system (INS, Inertial Navigation System) is a kind of navigational system of utilizing inertial sensor spare, reference direction and initial information such as position to determine orientation, position and the speed of carrier.Because inertial navigation system is fixed against the equipment of carrier self fully and navigates, can getting in touch of any sound, light, electricity, magnetic do not taken place with the external world, therefore it has independence, disguise, real-time and advantage such as round-the-clock, has obtained to use widely in navigation, guidance, location and the stable control of various carriers.

And a new developing direction of modern inertial navigation technology has been represented in the appearance of strap-down inertial technology and development, the English original meaning of " strapdown " this term is exactly " binding ", so-called strap-down inertial technology is exactly with inertia sensitive element, for example gyroscope and accelerometer directly are fixed on the carrier, measure three rotational angular velocities in this carrier relative inertness space and three linear accelerations component along vehicle coordinate system respectively by gyroscope and accelerometer; Be converted into along the acceleration of navigation coordinate system through coordinate transform degree of will speed up information again; Through calculating the various navigation informations such as position, speed, course and horizontal attitude that the back just can obtain carrier.

Because the inertia sensitive element (gyroscope and accelerometer) in the strapdown inertial navigation system is directly installed on the carrier, in the ideal case, each accelerometer should be installed in the same position of carrier exactly, but obviously this is impossible realize, because inertia sensitive element all has the dimensions, and the design of hardware installation site also is restricted, like this because physical deflection has appearred in accelerometer with respect to ideal position, its detected tangential force and centripetal force just are known as " size " effect so, because therefore the defective of strapdown computational algorithm the size effect error will occur.Especially carrier is when doing vibratory movement, and vibratory movement will provide stable acceleration error after overcommutation.Therefore, be necessary by modes such as the smart demarcation of system to eliminate the influence of this size effect error then with the method for software compensation with the size effect error separating of system and extract.

In the prior art, can derive the process that laser gyro assembled static drift parameter is demarcated continuously automatically, provide the arranged mode and the data processing method of concrete test position by setting up combination metering system compensating error model.This method can be isolated the static drift parameter of laser gyro combination effectively, provides foundation for computing machine carries out error compensation.But the scaling method of prior art can not degree of will speed up meter the size effect error and other error terms of accelerometer be effectively separated, also just can't realize the accurate demarcation of size effect error of accelerometer, influenced the navigation accuracy and the efficient of system.

Summary of the invention

The embodiment of the invention provides a kind of scaling method and device of size effect error of accelerometer, can realize the system-level accurate demarcation of size effect error of accelerometer, thereby farthest isolated other error terms of the size effect sum of errors accelerometer of accelerometer, and then promoted the navigation accuracy and the efficient of system.

The embodiment of the invention provides a kind of scaling method of size effect error of accelerometer, comprising:

Described gyroscope is demarcated, and the compensation gyro error;

Described system is rotated with different angular velocity, and when described system arrival same position, obtain the system level velocity error;

Obtain the size effect error of described accelerometer according to the variation of described system level velocity error.

Described described system is rotated with different angular velocity, specifically comprises:

The navigation coordinate system of described system is taken as the free azimuth coordinate system that moves about, and rotates according to predefined mode respectively.

Described predefined mode specifically comprises:

Set the initial position of described system, and initialization system rotates around stationary shaft;

Described system is quickened rotation, uniform rotation and deceleration successively according to the angular acceleration of setting to rotate.

Described system arrives same position, specifically comprises:

According to the rotating manner of system, selecting the moment identical with the position in the initial moment is observation station.

The described initial moment is 0 second moment;

The identical moment of described position is the 16th second moment.

The embodiment of the invention also provides a kind of caliberating device of size effect error of accelerometer, comprising:

The initial acquisition unit is used for strapdown inertial navigation system is carried out preheating, and gathers the gyroscope in the described system and the output data of accelerometer;

The gyro error compensating unit is used for described gyroscope is demarcated, and the compensation gyro error;

System level velocity error acquiring unit is used for described system is rotated with different angular velocity, and obtains the system level velocity error when described system arrival same position;

Size effect error calibration unit is used for obtaining according to the variation of described system level velocity error the size effect error of described accelerometer.

Described device also comprises:

Rotate setup unit, be used for the navigation coordinate system of described system is taken as the free azimuth coordinate system that moves about, and rotate according to predefined mode respectively.

Described device is integrated to be arranged in the described strapdown inertial navigation system.

By the above-mentioned technical scheme that provides as can be seen, at first strapdown inertial navigation system is carried out preheating, and gather the gyroscope in the described system and the output data of accelerometer; Then described gyroscope is demarcated, and the compensation gyro error; Again described system is rotated with different angular velocity, and when described system arrival same position, obtain the system level velocity error; Obtain the size effect error of described accelerometer again according to the variation of described system level velocity error.So just can realize the system-level accurate demarcation of size effect error of accelerometer, thereby farthest isolate other error terms of the size effect sum of errors accelerometer of accelerometer, and then promote the navigation accuracy and the efficient of system.

Description of drawings

The schematic flow sheet of the embodiment of the invention 1 method that provides is provided Fig. 1;

The rotating manner synoptic diagram of presetting in the example that Fig. 2 is enumerated for the embodiment of the invention 1;

Corresponding rotary motion trace synoptic diagram in the example that Fig. 3 is enumerated for the embodiment of the invention 1;

Fig. 4 is that the embodiment of the invention 1 is through described strapdown inertial navitation system (SINS) horizontal velocity error change curve behind the simulation calculating;

Fig. 5 is the structural representation of 2 generators of the embodiment of the invention.

Embodiment

The embodiment of the invention provides a kind of scaling method and device of size effect error of accelerometer.By turntable rotary motion trace reasonable in design, excite the size effect error of strapdown inertial navigation system accelerometer, and observe the output of described system at same position, so just can estimate the size effect error of accelerometer by the variation of system level velocity error, thereby realized the system-level accurate demarcation of size effect error of accelerometer, and farthest isolated other error terms of the size effect sum of errors accelerometer of accelerometer, and then the navigation accuracy and the efficient of system have been promoted.

For better describing embodiment of the present invention, now in conjunction with the accompanying drawings the specific embodiment of the present invention is described, embodiment 1: the embodiment of the invention 1 provides a kind of scaling method of size effect error of accelerometer, is illustrated in figure 1 as the schematic flow sheet of described method, and described method comprises:

Step 11: strapdown inertial navigation system is carried out preheating, and gather the gyroscope in the described system and the output data of accelerometer.

In this step, at first open strapdown inertial navigation system, promptly strapdown inertial navigation system is carried out the preheating of certain hour, specifically to carry out the time of preheating and set according to the demand of described system, the time of general preheating was greater than 5 minutes.

Step 12: described gyroscope is demarcated, and the compensation gyro error.

In this step, before the size effect error of demarcating accelerometer, need to demarcate earlier and the compensation gyro error, this is owing to be to adopt the system level velocity error as observed quantity in the present invention, and the attitude error of system level velocity error and system also has relation, this system's attitude error is caused by gyrostatic error, therefore needs to demarcate earlier before the size effect error of demarcating accelerometer and the compensation gyro error.

For instance, at first set the error model of strapdown inertial navigation system, navigation coordinate system (being called for short n system) is herein adopted the local horizontal coordinates (oxyz) of N-E-D, taking into account system initial error not under quiet pedestal state is reduced to the error model of strapdown inertial navigation system as follows:

$\left\{\begin{array}{c}\mathrm{\δ}{\stackrel{\·}{v}}_x={\mathrm{\δf}}_x+g{\mathrm{\φ}}_y\\ \mathrm{\δ}{\stackrel{\·}{v}}_y={\mathrm{\δf}}_y-{\mathrm{g\φ}}_x\\ \mathrm{\δ}{\stackrel{\·}{v}}_z=\mathrm{\δ}{f}_z\\ {\stackrel{\·}{\mathrm{\φ}}}_x={\mathrm{\Ω}}_z{\mathrm{\φ}}_y-{\mathrm{\Ω}}_y{\mathrm{\φ}}_z+{\mathrm{\ϵ}}_x\\ {\stackrel{\·}{\mathrm{\φ}}}_y={\mathrm{\Ω}}_x{\mathrm{\φ}}_z-{\mathrm{\Ω}}_z{\mathrm{\φ}}_x+{\mathrm{\ϵ}}_y\\ {\stackrel{\·}{\mathrm{\φ}}}_z={\mathrm{\ϵ}}_z\end{array}\right.---\left(10\right)$

G represents local gravitational acceleration in the above-mentioned formula 10, and Ω represents earth rate, δ v representation speed error, and the attitude error of φ representative system, δ f represents accelerometer error, and ε represents gyro error; Subscript in the above-mentioned formula is represented the component of each physical quantity under corresponding navigation coordinate is.

And then the error model of setting device, the device error that needs here to demarcate is meant constant error, specifically comprises accelerometer and the gyrostatic zero size effect error of error, constant multiplier error, misalignment and accelerometer partially.O under carrier coordinate system _bx _by _bz _bThe error model of (being designated hereinafter simply as b system) definition device is as follows:

ε ^b＝gB ^b+(gMA ^b+I·gSF ^b)·ω ^b (11)

δf ^b＝aB ^b+(aMA ^b+I·aSF ^b)·f ^b+a _ep ^b (12)

Above-mentioned formula 11 and 12 can be write as following component form respectively:

$\left[\begin{array}{c}{\mathrm{\ϵ}}_x^b\\ {\mathrm{\ϵ}}_y^b\\ {\mathrm{\ϵ}}_z^b\end{array}\right]=\left[\begin{array}{c}{\mathrm{gb}}_x^b\\ {\mathrm{gb}}_y^b\\ {\mathrm{gb}}_z^b\end{array}\right]+\left[\begin{array}{ccc}{\mathrm{gSF}}_x& \mathrm{gM}{A}_{\mathrm{xy}}& {\mathrm{gMA}}_{\mathrm{xz}}\\ {\mathrm{gMA}}_{\mathrm{yx}}& \mathrm{gS}{F}_y& {\mathrm{gMA}}_{\mathrm{yz}}\\ {\mathrm{gMA}}_{\mathrm{zx}}& {\mathrm{gMA}}_{\mathrm{zy}}& {\mathrm{gSF}}_z\end{array}\right]\left[\begin{array}{c}{\mathrm{\ω}}_x^b\\ {\mathrm{\ω}}_y^b\\ {\mathrm{\ω}}_z^b\end{array}\right]---\left(13\right)$

$\left[\begin{array}{c}{\mathrm{\δf}}_x^b\\ {\mathrm{\δf}}_y^b\\ {\mathrm{\δf}}_z^b\end{array}\right]=\left[\begin{array}{c}{\mathrm{aB}}_x^2\\ {\mathrm{aB}}_y^2\\ {\mathrm{aB}}_z^2\end{array}\right]+\left[\begin{array}{ccc}{\mathrm{aSF}}_x& \mathrm{aM}{A}_{\mathrm{xy}}& {\mathrm{aMA}}_{\mathrm{xz}}\\ {\mathrm{aMA}}_{\mathrm{yx}}& \mathrm{aS}{F}_y& {\mathrm{aMA}}_{\mathrm{yz}}\\ {\mathrm{aMA}}_{\mathrm{zx}}& {\mathrm{aMA}}_{\mathrm{zy}}& {\mathrm{aSF}}_z\end{array}\right]\left[\begin{array}{c}{f}_x^b\\ f_y^b\\ f_z^b\end{array}\right]+\left[\begin{array}{c}{a}_{\mathrm{epx}}\\ a_{\mathrm{epy}}\\ a_{\mathrm{epz}}\end{array}\right]---\left(14\right)$

In the above-mentioned formula, gB ^bAnd aB ^bDo not represent zero inclined to one side error term of gyroscope, accelerometer, gMA and aMA are meant the misalignment error of gyroscope and accelerometer respectively, and gSF and aSF are meant the constant multiplier error of gyroscope and accelerometer, a respectively _EpIt is the size effect error of accelerometer.

In preceding two formulas of above-mentioned formula 10, in time period t=0～T, ask for the variable quantity of system level velocity error, can get:

$\left\{\begin{array}{c}\mathrm{\δ}{\stackrel{\·}{v}}_x\left(T\right)-\mathrm{\δ}{\stackrel{\·}{v}}_x\left(0\right)={\mathrm{\Δ\δf}}_x+g{\mathrm{\Δ\φ}}_y\\ \mathrm{\δ}{\stackrel{\·}{v}}_y\left(T\right)-\mathrm{\δ}{\stackrel{\·}{v}}_y\left(0\right)={\mathrm{\Δ\δf}}_y-g{\mathrm{\Δ\φ}}_x\end{array}\right.---\left(15\right)$

In the above-mentioned formula 15:

$\mathrm{\Δ\δf}=C_b^n\left(T\right)\mathrm{\δ}{f}^b\left(T\right)-C_b^n\left(0\right)\mathrm{\δ}{f}^b\left(0\right)---\left(16\right)$

$\mathrm{\Δ\φ}={\∫}_0^T{C}_b^n\left(t\right){\mathrm{\ϵ}}^b\mathrm{dt}---\left(17\right)$

Wherein, C _b ⁿ(t) be tied to the instantaneous strapdown matrix that n is from b constantly for t.

Same, above-mentioned formula 16 and 17 also can be write as the form of component:

$\mathrm{\Δ\δf}=$

$C_b^n\left(T\right)(\left[\begin{array}{c}{\mathrm{aB}}_x\\ {\mathrm{aB}}_y\\ {\mathrm{aB}}_z\end{array}\right]+\left[\begin{array}{ccc}{\mathrm{aSF}}_x& \mathrm{aM}{A}_{\mathrm{xy}}& {\mathrm{aMA}}_{\mathrm{xz}}\\ {\mathrm{aMA}}_{\mathrm{yx}}& \mathrm{aS}{F}_y& {\mathrm{aMA}}_{\mathrm{yz}}\\ {\mathrm{aMA}}_{\mathrm{zx}}& {\mathrm{aMA}}_{\mathrm{zy}}& {\mathrm{aSF}}_z\end{array}\right]\left[\begin{array}{c}{f}_x^b\left(T\right)\\ f_y^b\left(T\right)\\ f_z^b\left(T\right)\end{array}\right]+\left[\begin{array}{c}{a}_{\mathrm{epx}}\left(T\right)\\ a_{\mathrm{epy}}\left(T\right)\\ a_{\mathrm{epz}}\left(T\right)\end{array}\right])---\left(18\right)$

${-C}_b^n\left(0\right)(\left[\begin{array}{c}{\mathrm{aB}}_x\\ {\mathrm{aB}}_y\\ {\mathrm{aB}}_z\end{array}\right]+\left[\begin{array}{ccc}{\mathrm{aSF}}_x& \mathrm{aM}{A}_{\mathrm{xy}}& {\mathrm{aMA}}_{\mathrm{xz}}\\ {\mathrm{aMA}}_{\mathrm{yx}}& \mathrm{aS}{F}_y& {\mathrm{aMA}}_{\mathrm{yz}}\\ {\mathrm{aMA}}_{\mathrm{zx}}& {\mathrm{aMA}}_{\mathrm{zy}}& {\mathrm{aSF}}_z\end{array}\right]\left[\begin{array}{c}{f}_x^b\left(0\right)\\ f_y^b\left(0\right)\\ f_z^b\left(0\right)\end{array}\right]+\left[\begin{array}{c}{a}_{\mathrm{epx}}\left(0\right)\\ a_{\mathrm{epy}}\left(0\right)\\ a_{\mathrm{epz}}\left(0\right)\end{array}\right])$

$\mathrm{\Δ\φ}=$

${\∫}_0^T{C}_b^n\left(t\right)(\left[\begin{array}{c}{\mathrm{gB}}_x\\ {\mathrm{gB}}_y\\ {\mathrm{gB}}_z\end{array}\right]+\left[\begin{array}{ccc}{\mathrm{gSF}}_x& \mathrm{gM}{A}_{\mathrm{xy}}& {\mathrm{gMA}}_{\mathrm{xz}}\\ {\mathrm{gMA}}_{\mathrm{yx}}& \mathrm{gS}{F}_y& {\mathrm{gMA}}_{\mathrm{yz}}\\ {\mathrm{gMA}}_{\mathrm{zx}}& {\mathrm{gMA}}_{\mathrm{zy}}& {\mathrm{gSF}}_z\end{array}\right]\left[\begin{array}{c}{\mathrm{\ω}}_x^b\\ {\mathrm{\ω}}_y^b\\ {\mathrm{\ω}}_z^b\end{array}\right])\mathrm{dt}---\left(19\right)$

Like this, just can obtain the relation between inertia device error and the system level velocity error according to above-mentioned formula (15), (16), (18) and (19).

Specifically, with the system level velocity error as observed quantity, by formula (15) as can be seen the system level velocity error be relevant with accelerometer error and system's attitude error; And formula (18) illustrative system attitude error is caused by gyrostatic error, therefore needs to demarcate earlier before the size effect error of demarcating accelerometer and the compensation gyro error.

Step 13: described system is rotated with different angular velocity, and when described system arrival same position, obtain the system level velocity error.

In this step, after demarcating and compensating gyro error, the rotating manner of initialization system and rotary motion trace, and when described system arrival same position, obtain the system level velocity error.

According to the above-mentioned example of enumerating as can be known: the system level velocity error is relevant with accelerometer error and system's attitude error, can reduce system's attitude error by demarcating and compensate gyro error in the above-mentioned steps 12; And the specific force error is only relevant with system first and last position as can be seen by formula (17) and (19), as long as system first and last position is identical, zero in accelerometer error parameters such as error, constant multiplier sum of errors misalignment partially will not constitute influence to the specific force error; That is to say and when system rotates with different angular velocity so, will have only the size effect error of accelerometer in the specific force error as long as guarantee that the first and last position is identical.

System is exported with different angular velocity rotations and in the same position recording geometry, estimate to obtain the size effect error of accelerometer then by the variation of system level velocity error, realize the system-level accurate demarcation of size effect error of accelerometer.

In this step, system rotates and can preestablish according to the actual requirements with different angular velocity, specifically the navigation coordinate system of described system can be taken as the free azimuth coordinate system that moves about, and rotate according to predefined mode respectively.The mode of specifically setting can be at first set the initial position of described system, and initialization system to rotate around stationary shaft; Then this system being quickened rotation, uniform rotation and deceleration successively according to the angular acceleration of setting rotates.

Rotary motion trace synoptic diagram as shown in Figure 3 for example: in track one, can the initialization system initial position be east northeast ground (being the corresponding respectively north of x, y and z axle, Dong Hedi), and the rotary motion trace one of initialization system is to rotate around the Z axle; Then, system quickened to rotate with the angular acceleration of 0.25 π (circular constant) successively in 0～12 second, carried out uniform rotation in 12～20 seconds, in 20～32 seconds with-0.25 π rotation of slowing down; Same, the initial position that can also set track two is day east, north, and then rotates around X-axis according to above-mentioned rotating speed.

For instance, be illustrated in figure 2 as rotating manner synoptic diagram default in the example that present embodiment 1 enumerated, be illustrated in figure 3 as corresponding rotary motion trace synoptic diagram, two rotary motion trace among Fig. 3 are the above-mentioned rotating manner that sets for example.In Fig. 2: C _b ⁿ(0), C _b ⁿ(T) for 0 and two of T observation constantly b be tied to the instantaneous strapdown matrix of n system, observation alliance constantly is identical, gets the initial time of system calibrating constantly at t=0, that is:

ω in track 1 _z(0)=0; ω in track 2 _x(0)=0.

And system's arrival same position can be according to the rotating manner of system, and selecting the moment identical with the position in the initial moment is observation station.With the rotating manner of above-mentioned Fig. 2 and Fig. 3, can select the initial moment is 0 second moment, and the identical moment of described position is the 16th second moment.Specifically, at 0 second constantly, the position of system is 0; At 16 seconds constantly, the position of system is 30 π (circular constants); Because both differ 15 times of 2* π, so in above-mentioned two moment, system is in same position.

Step 14: the size effect error that obtains described accelerometer according to the variation of described system level velocity error.

In this step, after getting access to the system level velocity error, just can obtain the size effect error of described accelerometer according to the variation of system level velocity error.

Still describe with the above-mentioned instantiation of being lifted, according to rotary motion trace shown in Figure 3, the observation equation that can obtain size effect error of accelerometer is:

In track one, accelerometer error δ f is:

$\mathrm{\Δ\δf}=$

$C_b^n\left(T\right)(\left[\begin{array}{c}a{B}_x\\ {\mathrm{aB}}_y\\ a{B}_z\end{array}\right]+g\left[\begin{array}{c}{\mathrm{aMA}}_{\mathrm{xz}}\\ {\mathrm{aMA}}_{\mathrm{yz}}\\ {\mathrm{aSF}}_z\end{array}\right]+\left[\begin{array}{c}{a}_{\mathrm{epx}}\left(T\right)\\ a_{\mathrm{epy}}\left(T\right)\\ a_{\mathrm{epz}}\left(T\right)\end{array}\right])$

$-C_b^n\left(0\right)(\left[\begin{array}{c}a{B}_x\\ {\mathrm{aB}}_y\\ a{B}_z\end{array}\right]+g\left[\begin{array}{c}{\mathrm{aMA}}_{\mathrm{xz}}\\ {\mathrm{aMA}}_{\mathrm{yz}}\\ {\mathrm{aSF}}_z\end{array}\right]+\left[\begin{array}{c}{a}_{\mathrm{epx}}\left(0\right)\\ a_{\mathrm{epy}}\left(0\right)\\ a_{\mathrm{epz}}\left(0\right)\end{array}\right])$

$=\left[\begin{array}{c}{a}_{\mathrm{epx}}\left(T\right)\\ a_{\mathrm{epy}}\left(T\right)\\ a_{\mathrm{epz}}\left(T\right)\end{array}\right]-\left[\begin{array}{c}{a}_{\mathrm{epx}}\left(0\right)\\ a_{\mathrm{epy}}\left(0\right)\\ a_{\mathrm{epz}}\left(0\right)\end{array}\right]=-\left[\begin{array}{c}{\mathrm{\ω}}_z^2\left(T\right)\·r_{\mathrm{px}}\\ {\mathrm{\ω}}_z^2\left(T\right)\·r_{\mathrm{py}}\\ 0\end{array}\right]---\left(20\right)$

System's attitude error is:

$\mathrm{\Δ\φ}=$

${\∫}_0^T{C}_b^n\left(t\right)(\left[\begin{array}{c}{\mathrm{gB}}_x\\ g{B}_y\\ {\mathrm{gB}}_z\end{array}\right]+\left[\begin{array}{ccc}{\mathrm{gSF}}_x& -& -\\ {\mathrm{gMA}}_{\mathrm{yx}}& -& -\\ {\mathrm{gMA}}_{\mathrm{zx}}& -& -\end{array}\right]\left[\begin{array}{c}0\\ 0\\ {\mathrm{\ω}}_z^b\end{array}\right])\mathrm{dt}---\left(21\right)$

In process above-mentioned steps 12, to demarcate gyroscope and also compensate after the gyro error, " the attitude error Δ φ of system " is in a small amount in the short time, so just formula (15) can be reduced to:

$\mathrm{\δ}{\stackrel{\·}{v}}_x\left(T\right)-\mathrm{\δ}{\stackrel{\·}{v}}_x\left(0\right)={\mathrm{\Δ\δf}}_x^n=-{\mathrm{\ω}}_z^2\left(T\right)\·r_{\mathrm{px}}---\left(22\right)$

$\mathrm{\δ}{\stackrel{\·}{v}}_y\left(T\right)-\mathrm{\δ}{\stackrel{\·}{v}}_y\left(0\right)={\mathrm{\Δ\δf}}_y^n=-{\mathrm{\ω}}_z^2\left(T\right)\·r_{\mathrm{py}}---\left(23\right)$

Same, in rotary motion trace two:

$\mathrm{\δ}{\stackrel{\·}{v}}_y\left(T\right)-\mathrm{\δ}{\stackrel{\·}{v}}_y\left(0\right)={\mathrm{\Δ\δf}}_y^n={\mathrm{\ω}}_x^2\left(T\right)\·r_{\mathrm{pz}}---\left(24\right)$

At last, aggregative formula (22), (23) reach (24) again, and the observation equation that just can obtain size effect error of accelerometer is as follows:

Rotary motion trace 1:

$r_{\mathrm{px}}=-\left(\frac{{\mathrm{\δ}\stackrel{\·}{v}}_x\left(T\right)-\mathrm{\δ}{\stackrel{\·}{v}}_x\left(0\right)}{{\mathrm{\ω}}_z^2\left(T\right)}\right)$

With

$r_{\mathrm{py}}=-\left(\frac{{\mathrm{\δ}\stackrel{\·}{v}}_y\left(T\right)-\mathrm{\δ}{\stackrel{\·}{v}}_y\left(0\right)}{{\mathrm{\ω}}_z^2\left(T\right)}\right)$

Rotary motion trace 2:

$r_{\mathrm{pz}}=\frac{{\mathrm{\δ}\stackrel{\·}{v}}_y\left(T\right)-\mathrm{\δ}{\stackrel{\·}{v}}_y\left(0\right)}{{\mathrm{\ω}}_x^2\left(T\right)}$

Wherein, the size effect error a of above-mentioned accelerometer _EpAnd r _pBetween have a following corresponding relation:

$a_{\mathrm{epx}}=r_{\mathrm{pxx}}({\mathrm{\ω}}_y^2+{\mathrm{\ω}}_z^2);$

$a_{\mathrm{epy}}=r_{\mathrm{pyy}}({\mathrm{\ω}}_x^2+{\mathrm{\ω}}_z^2);$

$a_{\mathrm{epz}}=r_{\mathrm{pzz}}({\mathrm{\ω}}_x^2+{\mathrm{\ω}}_y^2).$

Wherein, (x, y z) represent the component of each physical quantity under corresponding navigation coordinate is to the subscript in the above-mentioned formula.

Technical scheme by above-mentioned specific embodiment 1, just can realize the system-level accurate demarcation of size effect error of accelerometer, and farthest isolated other error terms of the size effect sum of errors accelerometer of accelerometer, and then the navigation accuracy and the efficient of system have been promoted.

For the effect that checking the foregoing description 1 technical scheme is produced, can utilize computing machine to carry out corresponding emulation experiment, specifically, the condition of at first setting l-G simulation test is as follows:

1) the systematic error distribution is estimated as shown in table 1 below:

(table 1)

2) parameter in the wave filter chosen of navigation calculation is as shown in table 2 below:

P(0)＝diag{(0.01m/s) 2，(0.01m/s) 2， (0.1m/s 2) 2，(0.1m/s 2) 2}

Q(0)＝diag{(0.02m/s 2) 2，(0.02m/s 2) 2， (0.04m/s 3) 2，(0.04m/s 3) 2}

R＝diag{(0.001m/s) 2}

(table 2)

3) T.T. of emulation is set at 32 seconds, and rotating manner and rotary motion trace are as shown in Figures 2 and 3.

Through after the above-mentioned setting, utilize computing machine to carry out simulation calculating, obtain the horizontal velocity of strapdown inertial navitation system (SINS) described in simulation process error change curve, described change curve is as shown in Figure 4.

Then,, just can obtain the emulation estimated result of size effect error of accelerometer according to the change curve of this system level velocity error, shown in the table 3 specific as follows:

The size effect error	Setting value (m)	Simulation result (m)	Stated accuracy
				The X-axis size effect error of accelerometer	0.04	0.0384	95.9％
The Y-axis size effect error of accelerometer	0.05	0.0513	97.4％
				Z axis accelerometer size effect error	0.06	0.0607	99.3％

(table 3)

By above-mentioned table 3 as seen, the foregoing description 1 described method has realized the system-level accurate demarcation of size effect error of accelerometer, has promoted the navigation accuracy and the efficient of system.

Embodiment 2: the embodiment of the invention 2 provides a kind of caliberating device of size effect error of accelerometer, be illustrated in figure 5 as the structural representation of 2 generators of present embodiment, described device comprises initial acquisition unit, gyro error compensating unit, system level velocity error acquiring unit and size effect error calibration unit, wherein:

Described initial acquisition unit is used for strapdown inertial navigation system is carried out preheating, and gathers the gyroscope in the described system and the output data of accelerometer.

Described gyro error compensating unit is used for described gyroscope is demarcated, and the compensation gyro error; The mode that specifically compensates is seen described in the above method embodiment 1.

Described system level velocity error acquiring unit is used for described system is rotated with different angular velocity, and obtains the system level velocity error when described system arrival same position.Concrete obtain manner is seen described in the above method embodiment 1.

Described size effect error calibration unit is used for obtaining according to the variation of described system level velocity error the size effect error of described accelerometer.The mode that concrete estimation obtains is seen described in the above method embodiment 1.

In addition, described device also can comprise the rotation setup unit, and this rotation setup unit is used for the navigation coordinate system of described system is taken as the free azimuth coordinate system that moves about, and rotates according to predefined mode respectively.

The above installs integrated being arranged in the described strapdown inertial navigation system; Or be arranged to independent functional entity.

It should be noted that among the said apparatus embodiment that each included unit is just divided according to function logic, but is not limited to above-mentioned division, as long as can realize function corresponding; In addition, the concrete title of each functional unit also just for the ease of mutual differentiation, is not limited to protection scope of the present invention.

In addition, one of ordinary skill in the art will appreciate that all or part of step that realizes in the foregoing description method is to instruct relevant hardware to finish by program, corresponding program can be stored in a kind of computer-readable recording medium, the above-mentioned storage medium of mentioning can be a ROM (read-only memory), disk or CD etc.

In sum, the embodiment of the invention has realized the system-level accurate demarcation of size effect error of accelerometer, and farthest isolated other error terms of the size effect sum of errors accelerometer of accelerometer, and then the navigation accuracy and the efficient of system have been promoted.

The above; only for the preferable embodiment of the present invention, but protection scope of the present invention is not limited thereto, and anyly is familiar with those skilled in the art in the technical scope that the present invention discloses; the variation that can expect easily or replacement all should be encompassed within protection scope of the present invention.Therefore, protection scope of the present invention should be as the criterion with the protection domain of claims.

Claims (8)

1, a kind of scaling method of size effect error of accelerometer is characterized in that:

Described gyroscope is demarcated, and the compensation gyro error;

Described system is rotated with different angular velocity, and when described system arrival same position, obtain the system level velocity error;

Obtain the size effect error of described accelerometer according to the variation of described system level velocity error.

2, the method for claim 1 is characterized in that, described described system is rotated with different angular velocity, specifically comprises:

The navigation coordinate system of described system is taken as the free azimuth coordinate system that moves about, and rotates according to predefined mode respectively.

3, method as claimed in claim 2 is characterized in that, described predefined mode specifically comprises:

Set the initial position of described system, and initialization system rotates around stationary shaft;

Described system is quickened rotation, uniform rotation and deceleration successively according to the angular acceleration of setting to rotate.

As claim 2 or 3 described methods, it is characterized in that 4, described system arrives same position, specifically comprises:

According to the rotating manner of system, selecting the moment identical with the position in the initial moment is observation station.

5, method as claimed in claim 4 is characterized in that,

The described initial moment is 0 second moment;

The identical moment of described position is the 16th second moment.

6, a kind of caliberating device of size effect error of accelerometer is characterized in that, comprising:

The initial acquisition unit is used for strapdown inertial navigation system is carried out preheating, and gathers the gyroscope in the described system and the output data of accelerometer;

The gyro error compensating unit is used for described gyroscope is demarcated, and the compensation gyro error;

System level velocity error acquiring unit is used for described system is rotated with different angular velocity, and obtains the system level velocity error when described system arrival same position;

Size effect error calibration unit is used for obtaining according to the variation of described system level velocity error the size effect error of described accelerometer.

7, device as claimed in claim 6 is characterized in that, described device also comprises:

Rotate setup unit, be used for the navigation coordinate system of described system is taken as the free azimuth coordinate system that moves about, and rotate according to predefined mode respectively.

As claim 6 or 7 described devices, it is characterized in that 8, described device is integrated to be arranged in the described strapdown inertial navigation system.

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