CN103913179A - Ship-based single-axial rotation modulation strapdown inertial navigation attitude angle correction method - Google Patents

Abstract

The invention relates to a ship-based single-axial rotation modulation strapdown inertial navigation attitude angle correction method, which belongs to the technical field of inertial navigation. The method comprises the following steps: creating the test condition for attitude angle error correction; constructing an attitude angle error correction mathematics model; calibrating an attitude angle correction parameter; and correcting and compensating the attitude angle error. The correction is carried out on the ship-based single-axial rotation modulation strapdown inertial navigation attitude angle, and the influence of the single-axial rotation platform inclination on the attitude angle data can be effectively reduced in a reasonable mode. The method has important usage value for increasing the precision of the single-axial rotation modulation strapdown inertial navigation attitude angle and developing the application of the equipment on the ships.

Description

Carrier-borne single-shaft-rotation modulation SINS Attitude corner correcting method

Technical field

The present invention relates to a kind of carrier-borne single-shaft-rotation modulation SINS Attitude angle error parameter calibration and compensation method.

Background technology

Strapdown inertial navitation system (SINS) is a developing direction of inertial technology in recent years.From the analysis of development situation of external inertial navigation system, inertial navigation progressively replaces traditional Platform INS becomes the main flow of most applications.In sea base TT&C task, simple inertial navigation is difficult to meet the requirements for high precision of instrumented tracking and telemetry ship to attitude angle, thereby adopts single-shaft-rotation modulation scheme.

There is inevitable droop error in processing with in installing in single-shaft-rotation platform, directly has influence on the precision of attitude angle data or even the normal use of equipment.Can address the above problem from the following aspect in theory, the one, the precision of raising single-shaft-rotation platform, but production and processing is strictly subject to the restriction of material and technique, the 2nd, design and adopt high-precision strapdown algorithm, but have great difficulty and can sharply increase cost; The 3rd, adopt attitude error correction technique, need testing program and data processing method reasonable in design.Comprehensive analysis, adopts attitude error correction technique, testing program reasonable in design, and research attitude error correction technique can effectively limit and reduce the impact of single-shaft-rotation platform inclination on attitude angle data.

Although equipment development factory droop error (axle is parameter) to turntable demarcate and revise, but in process of the test, still find to exist obvious remainder error, main manifestations is the ladder error phenomenon that obvious attitude error is relevant to the turntable anglec of rotation.

Summary of the invention

The object of the invention is to overcome above-mentioned deficiency, a kind of carrier-borne single-shaft-rotation modulation SINS Attitude corner correcting method is provided, revise with single-shaft-rotation modulation SINS Attitude angle carrying test, effectively reduce the impact of single-shaft-rotation platform inclination on attitude angle data.

The object of the present invention is achieved like this: a kind of carrier-borne single-shaft-rotation modulation SINS Attitude corner correcting method, said method comprising the steps of:

Step 1, determine attitude error correction test condition

This method can be implemented under inertial navigation static state or current intelligence.Under static condition, 1/3, three attitude angle (rolling R, pitching P, course H) that requires in calibration process the attitude angle of the pedestal for inertial navigation is installed itself to change the attitude error that is not more than inertial navigation output is exported and be can be considered fixed value.Under dynamic condition, requiring inertial navigation to be calibrated (being called for short SINS) and comparison basis equipment (as Platform INS is called for short INS) to connect firmly is arranged on same pedestal, the measuring accuracy of comparison basis equipment is not less than the precision index of inertial navigation to be calibrated, and the data of two complete equipments have completed coordinate system and even up.

Step 2, set up attitude error correction mathematical model

Under static condition using fixed value (rolling R, the pitching P of inertial navigation, tri-attitude angle of course H) known in step 1 as comparison basis, under dynamic condition using the output attitude of comparison basis equipment (as INS) as benchmark, synchronous admission attitude error Δ R, Δ P, Δ H and turntable angle Kp, draw Δ R, Δ P, Δ H and Kp relation curve, can find the trigonometric function feature meeting between them, press trigonometric function method for parameter estimation, available following error model represents:

(1)

In formula (1), R ₀, P ₀, H ₀be respectively the normal value component of three attitude errors, A _r, A _p, A _hbe the amplitude of three attitude errors, Φ _r, Φ _p, Φ _hbe the initial phase of three attitude errors, Kp is turntable angle.R ₀, P ₀, H ₀, A _r, A _p, A _h, Φ _r, Φ _p, Φ _hbe 9 parameters to be calibrated in error model.

Three, attitude error corrected parameter is demarcated

Demarcate for convenient, formula (1) is rewritten as

(2)

In formula (2), , , here i=R, P, H.

In formula (2), only need to obtain the corresponding Δ i(i=R of three Kp, P, H) value, can determine i ₀, a _i, b _ithree parameters.Turn and stop single-shaft-rotation inertial navigation for multiposition (n position), the attitude error average of desirable turntable stop position as error observed quantity, set up observation equation:

(3)

In formula (3)

The least square solution of formula (3) is

(4)

Determined by formula (4) i ₀, a _i , b _i after, , , and according to a _i , b _i symbol is determined Φ _i quadrant.

Four, attitude error correction-compensation method

After attitude error parameter calibration, can calculate in real time attitude error value Δ R, Δ P, the Δ H of any turntable angle according to formula (1), by uncorrected real-time measurement values R, P, H deduct respectively Δ R, Δ P, Δ H can obtain revised measured value.

In actual calibration process, rolling, two horizontal attitude angles of pitching, used the method can obtain good result.Except outside the Pass having with turntable angle, also there is inverse relationship with rotation platform angular velocity of rotation in course error, need to utilize turntable angular velocity to take advantage of a scale factor further to carry out comprehensive compensation to course data again.

Compared with prior art, the invention has the beneficial effects as follows:

The present invention is by the method that SINS attitude angle data Output rusults is revised, eliminate the impact of single axle table platform inclination on SINS attitude angle data, improve SINS attitude angle precision, with minimum cost, experimental prototype is applied to through engineering approaches, having evaded must be by improving turntable precision or changes strapdown algorithm a difficult problem that improves attitude angle precision.

Brief description of the drawings

Fig. 1 is the attitude angle curve of output under single-shaft-rotation inertial navigation static condition.

Fig. 2 is attitude error curve under single-shaft-rotation inertial navigation and comparison basis (Platform INS) dynamic condition.

Fig. 3 is single-shaft-rotation SINS Attitude angle error and turntable angle trigonometric function relation curve.

Fig. 4 is that single-shaft-rotation inertial navigation transverse and longitudinal is shaken correction result.

Fig. 5 is single-shaft-rotation inertial navigation course correction result.

Embodiment

Referring to Fig. 1-Fig. 5, the present invention relates to a kind of carrier-borne single-shaft-rotation modulation SINS Attitude corner correcting method, taking certain type single-shaft-rotation modulation inertial navigation rotation modulation scheme as: stage body intrinsic coordinates is 0o → 180o → 270o → 90o → 0o, each position residence time 300s, angular velocity of rotation 10o/s, cycle (not containing rotary movement) 1200s.

If attitude angle data do not compensate and correct, error can be very large, and horizontal attitude ladder peak-to-peak value reaches 70 ", course peak-to-peak value reaches 120 ".

Attitude angle correction implementation step:

Adopt the attitude angular difference mean value of 0 °, 180 °, 270 °, 90 ° four transpositions of stage body as observed quantity, with R ₀, a _r, b _rwrite as matrix form as solve for parameter:

(5)

In formula (5)

The least square solution of formula (5) is

(6)

Adopting uses the same method can determine three parameter P of pitching ₀, a _p, b _p, parameter estimation the results are shown in Table 1.

Table 1 SINS horizontal attitude error parameter estimated result

Adopting uses the same method can determine three Parameter H in course ₀, a _h, b _h, parameter estimation the results are shown in Table 2, wherein H ₀do not revise.

Table 2 SINS course error parameter estimation result

H0	aH	bH	AH	ΦH
					--	35.01″	-60.98″	70.32″	150.89°

In the calibration process of course, because the Platform INS course error of comparison is unstable, H ₀parameter is without practical significance, thus do not demarcate and compensate, need to be after horizontal parametric compensation, more high-precision course comparison basis (latitude instrument is surveyed asterisk vectoring error) is determined.

Attitude angle correction result of implementation:

Utilize table 1 parameter of least square method estimation respectively to rolling, pitching compensation data, the ladder error phenomenon that is tilted to cause by rotation platform is eliminated.

Utilize table 1 parameter of least square method estimation to course angle compensation data.The ladder error phenomenon that is tilted to cause by rotation platform is eliminated, but attitude angle in turntable rotary course exists larger burr.Find burr size approximately 40 ", direction and rotation platform angular velocity opposite direction, in view of rule wherein, utilize turntable angular velocity to take advantage of a coefficient to do further compensation to course data again in analytic process, and burr phenomena disappears substantially.

Attitude angle data precision after compensation:

This type inertial navigation pitching, rolling and Platform INS after compensation compared total error and is respectively 5.8 " and 5.3 "; Comparing course error total error with transit survey star result is 8.0 ", meet inertial navigation index and carrier-borne application requirements, illustrate that this compensation method is effective, feasible.

Claims (1)

1. a carrier-borne single-shaft-rotation modulation SINS Attitude corner correcting method, its feature arrogant with said method comprising the steps of:

Step 1, determine attitude error correction test condition

Under static condition, the attitude angle of mounting base itself change be not more than inertial navigation output attitude error 1/3, rolling R, pitching P, tri-attitude angle outputs of course H are considered as fixed value; Under dynamic condition, inertial navigation and comparison basis equipment connect firmly and are arranged on together on pedestal, and the measuring accuracy of comparison basis equipment is not less than the precision index of inertial navigation to be calibrated, and the data of two complete equipments have completed coordinate system and even up;

Step 2, set up attitude error correction mathematical model

Synchronous admission attitude error Δ R, Δ P, Δ H and turntable angle Kp, draw Δ R, Δ P, Δ H and Kp relation curve, and by trigonometric function method for parameter estimation, available following error model represents:

(1)

In formula (1), R ₀, P ₀, H ₀be respectively the normal value component of three attitude errors, A _r, A _p, A _hbe the amplitude of three attitude errors, Φ _r, Φ _p, Φ _hbe the initial phase of three attitude errors, Kp is turntable angle;

Three, attitude error corrected parameter is demarcated

Formula (1) is rewritten as

(2)

In formula (2), , , here i=R, P, H;

Get the attitude error average of turntable stop position as error observed quantity, set up observation equation:

(3)

In formula (3)

The least square solution of formula (3) is

(4)

Determined by formula (4) i ₀, a _i , b _i after, , , and according to a _i , b _i symbol is determined Φ _i quadrant;

Four, attitude error correction-compensation method

After attitude error parameter calibration, can calculate in real time attitude error value Δ R, Δ P, the Δ H of any turntable angle according to formula (1), by uncorrected real-time measurement values R, P, H deduct respectively Δ R, Δ P, Δ H can obtain revised measured value.