CN102538825B - Optical axis orientation calibrating method of star sensor probe assembly - Google Patents

Abstract

The invention discloses an optical axis orientation calibrating method of a star sensor probe assembly, which comprises the steps of: before the star sensor probe assembly is assembled and mounted, respectively calibrating three star sensors of the star sensor probe assembly by using a photographic surveying method, so as to obtain a conversion relation between each star sensor coordinate system and a corresponding star sensor standard lens; establishing a theodolite surveying system at least comprising six theodolites: at first, establishing the theodolite surveying system by mutually pointing of any two of the theodolites, secondly, collimating the standard lens of one of the star sensors by using each two theodolites to obtain a relation of the three star sensor standard lenses relative to the star sensor coordinate system, and finally, obtaining a relation among the three star sensor standard lenses according to the relation of the three star sensor standard lenses relative to the star sensor coordinate system; and finally, obtaining the relation among the three star sensor coordinate systems according to the relation among the three star sensor standard lenses, so as to calibrate an optical axis orientation of the star sensor probe assembly.

Description

A kind of star sensor probe assembly optical axis orientation calibrating method

Technical field

The present invention relates to a kind of star sensor probe optical axis orientation calibrating method, relate in particular to a kind of star sensor probe assembly optical axis orientation calibrating method, belong to vision measurement field.

Background technology

Star sensor assembly is to adopt three probe Rotating Platform for High Precision Star Sensor and the integrated structures of complex configuration star sensor holder combination, this kind of configuration reduced satellite and used star sensor to measure the transmission error between attitude and load operating attitude, improved satellite elements of interior orientation high stability problem in-orbit.According to measurement scheme, to the measurement of relation between the quick reference mirror of each star of star sensor assembly, need to set up the transformational relation between mechanical coordinate system and platform prism square by measurement, relation between the quick prism square of platform prism square and star, three axle position relations between three prism square coordinate systems of micrometric measurement simultaneously.Owing to determining that three axle position relation precision prescribeies between three prism square coordinate systems are very high, existing equipment and software can not meet measuring accuracy requirement, need retrofit testing method, realize the accurate measurement of relation between prism square.

Summary of the invention

Technology of the present invention is dealt with problems and is: overcome the deficiencies in the prior art, a kind of star sensor probe assembly optical axis orientation calibrating method is provided, realize the accurate measurement between the sensing of star sensor assembly optical axis, work efficiency and stated accuracy are high.

Technical solution of the present invention is: a kind of star sensor probe assembly optical axis orientation calibrating method, and step is as follows:

(1) before the combination of star sensor probe assembly is installed, utilize photogrammetric survey method to demarcate respectively 3 of star sensor probe assembly star sensors, obtain the transformational relation between the quick device reference mirror of each star sensor coordinate system and this star, the star sensor probe of having demarcated is combined to installation;

(2) set up the transit survey system that comprises at least 6 transits, first utilize any 2 transits mutually to take aim at mutually and set up transit coordinate system, then utilize every two transits to collimate and obtain the relation of 3 relative transit coordinate systems of star sensor reference mirror the reference mirror of one of them star sensor, finally obtain 3 relations between star sensor reference mirror according to the relation of 3 relative transit coordinate systems of star sensor reference mirror;

(3) utilize the relation between 3 star sensor reference mirror that transformational relation between single star sensor coordinate system and this star sensor reference mirror that step (1) obtains and step (2) obtain to obtain the relation between three star sensor coordinate systems, thereby realize the demarcation that star sensor probe assembly optical axis is pointed to.

The implementation method of described step (1) is:

(1) set up the coordinate system of transit survey system, the reference mirror to each star sensor under transit survey system coordinate system collimates, and obtains the relative parameter of star sensor reference mirror under transit survey system coordinate system;

(2) utilize transit survey system to measure Calibration Field, obtain the three-dimensional coordinate of Calibration Field mark under transit survey system coordinate system;

(3) utilize common point conversion, obtain the transformational relation of Calibration Field coordinate system and transit survey system coordinate system, thereby obtain the relation of star sensor reference mirror and Calibration Field coordinate system;

(4) utilize separate unit star sensor to the Calibration Field imaging of taking pictures, utilize resection method to obtain the relation of star sensor coordinate system and Calibration Field coordinate system, obtain the relation between separate unit star sensor coordinate system and this star sensor reference mirror.

In described step (2), utilize any 2 transits mutually to take aim at mutually to set up the method for transit coordinate system to be:

(1) the telescope Focussing of two transits is arrived to position, infinite distance, thereby take aim at mutually crosshair, two parallel to each other completing mutually of transit collimation axis are taken aim at;

(2) taking any transit in 6 transits as survey station 1, survey station 1 is true origin, any transit of choosing in all the other 5 transits is survey station 2, the line of survey station 1 and survey station 2 in the horizontal direction be projected as X-axis, the vertical of crossing survey station 1 is Z axis, determine Y-axis with right-hand rule, form transit coordinate system.

4, a kind of star sensor probe assembly optical axis orientation calibrating method according to claim 1, it is characterized in that: the method that obtains the relation of 3 relative transit coordinate systems of star sensor reference mirror in described step (2) is: every two transits collimate to adjacent two minute surfaces of a star sensor reference mirror, obtain the X-axis vector sum Y-axis amount of adjacent two minute surfaces, utilize right-hand rule to obtain Z-axis direction amount, set up reference mirror coordinate system according to three axial vectors of reference mirror, the rotation matrix of reference mirror coordinate system and transit coordinate system is:

$R=\left[\begin{array}{ccc}\cos {\mathrm{\α}}_x& \cos {\mathrm{\β}}_x& \cos {\mathrm{\γ}}_x\\ \cos {\mathrm{\α}}_y& \cos {\mathrm{\β}}_y& \cos {\mathrm{\γ}}_y\\ \cos {\mathrm{\α}}_z& \cos {\mathrm{\β}}_z& \cos {\mathrm{\γ}}_z\end{array}\right],$

Wherein:

α _xfor the X-axis of reference mirror coordinate system is with respect to the angle of transit coordinate system X-axis,

β _xfor the X-axis of reference mirror coordinate system is with respect to the angle of transit coordinate system Y-axis,

γ _xfor the X-axis of reference mirror coordinate system is with respect to the angle of transit coordinate system Z axis,

α _yfor the Y-axis of reference mirror coordinate system is with respect to the angle of transit coordinate system X-axis,

β _yfor the Y-axis of reference mirror coordinate system is with respect to the angle of transit coordinate system Y-axis,

γ _yfor the Y-axis of reference mirror coordinate system is with respect to the angle of transit coordinate system Z axis,

α _zfor the Z axis of reference mirror coordinate system is with respect to the angle of transit coordinate system X-axis,

β _zfor the Z axis of reference mirror coordinate system is with respect to the angle of transit coordinate system Y-axis,

γ _zfor the Z axis of reference mirror coordinate system is with respect to the angle of transit coordinate system Z axis.

The present invention's advantage is compared with prior art: the present invention utilizes photogrammetric technology to measure star sensor elements of exterior orientation, adopt the three-dimensional coordinate measurement of industrial measuring system and the non-focusing of high precision based on three probe star sensor optical reference conversions to take aim at mutually with many survey time and resolve measuring method, transformational relation between the high-precision star sensor coordinate system of final acquisition and reference mirror, solve star sensor assembly optical axis pointing space orientation calibration problem, have higher work efficiency and stated accuracy, calibrated error reaches a second class precision.

Brief description of the drawings

Fig. 1 is the structural representation of star sensor probe assembly;

Fig. 2 is that star sensor probe assembly optical axis points to schematic diagram;

Fig. 3 is demarcation process flow diagram of the present invention;

Fig. 4 is space intersection schematic diagram;

Fig. 5 is star sensor reference mirror coordinate system schematic diagram.

Embodiment

Star sensor assembly as shown in Figure 1, star sensor assembly is to adopt three probe Rotating Platform for High Precision Star Sensor 3, star sensor support 2 and base 1 integral structures, star sensor support 2 adopts the dendritic configuration being made up of three branches, this kind of configuration reduced satellite and used star sensor to measure the transmission error between attitude and load operating attitude, improved satellite elements of interior orientation high stability problem in-orbit.Star sensor base 1 by casting or integrally welded, is all installed a star sensor probe 3 with star sensor support 2 on each branch of star sensor support 2.

Star sensor points to requirement, during for guarantee star sensor operation on orbit, there is good visual field environment, optical axis to star sensor under whole star coordinate system points to and designs, as shown in Figure 2, need ensure that star sensor points to when star sensor support Design requires (following reference coordinate is whole star coordinate system): whole star Coordinate system definition is as follows: true origin O: the theoretical center of circle of satellite and the rocket parting plane (satellite bearing cylinder lower flange lower surface); X-axis: cross true origin, perpendicular to satellite and the rocket parting plane, along the y direction of satellite, point to the same longitudinal axis; Z axis: cross true origin, be positioned at satellite and the rocket parting plane, point to satellite normal flight direction over the ground; Y-axis: be positioned at satellite and the rocket parting plane, form right-handed system with X-axis, Z axis.

Pass between three branches of star sensor support is: the central shaft of the first branch and whole star coordinate system YOZ face angle are 25 °, with whole star coordinate system+X-axis angle be 65 degree, projection and whole star coordinate system+Y-axis angle in whole star coordinate system OYZ plane are 25 °, with whole star coordinate system-Z axis angle be 65 °; The central shaft of the second branch and whole star coordinate system OXZ plane included angle are 30 °, with 60 ° of whole star coordinate system+Y-axis angles, are 70 ° at projection and whole star coordinate system-X-axis angle of whole star coordinate system OXZ plane, with whole star coordinate system-Z axis angle be 20 °; The central shaft of the 3rd branch and whole star coordinate system OXZ plane included angle are 25 °, with 65 ° of whole star coordinate system+Y-axis angles, are 25 ° at projection and whole star coordinate system+X-axis angle of whole star coordinate system OXZ plane, with whole star coordinate system-Z axis angle be 65 °.

As shown in Figure 3, be the process flow diagram of the inventive method, specific implementation step is as follows:

(1) before the combination of star sensor probe assembly is installed, utilize photogrammetric survey method to demarcate respectively 3 of star sensor probe assembly star sensors, obtain the transformational relation between the quick device reference mirror of each star sensor coordinate system and this star, the star sensor probe of having demarcated is combined to installation;

The implementation method of step (1) is:

(a) set up the coordinate system of transit survey system, the reference mirror to each star sensor under transit survey system coordinate system collimates, and obtains the relative parameter of star sensor reference mirror under transit survey system coordinate system; Star sensor external parameter mutually: be used for representing position that star sensor preferred coordinate system is lower and one group of parameter of direction, the angular orientation element RX that the volume coordinate Xs that comprises its central point, Ys, Zs and its spatial axes are, RY, RZ.

(b) utilize transit survey system to measure Calibration Field, obtain the three-dimensional coordinate of Calibration Field mark under transit survey system coordinate system;

(c) utilize common point conversion, obtain the transformational relation of Calibration Field coordinate system and transit survey system coordinate system, thereby obtain the relation of star sensor reference mirror and Calibration Field coordinate system;

(d) utilize separate unit star sensor to the Calibration Field imaging of taking pictures, utilize resection method to obtain the relation of star sensor coordinate system and Calibration Field coordinate system, obtain the relation between separate unit star sensor coordinate system and this star sensor reference mirror.

(2) set up the transit survey system that comprises at least 6 transits, first utilize any 2 transits mutually to take aim at mutually and set up transit coordinate system, then utilize every two transits to collimate and obtain the relation of 3 relative transit coordinate systems of star sensor reference mirror the reference mirror of one of them star sensor, finally obtain 3 relations between star sensor reference mirror according to the relation of 3 relative transit coordinate systems of star sensor reference mirror;

The foundation of transit survey system: each star sensor will be measured at the both direction of reference mirror, i.e. reference mirror of every measurement needs 2 transits; While setting up measuring system, must first collimate respectively the reference mirror of three star sensors, after collimation is good, instrument can not make any adjustments.Measuring star sensor probe assembly need to have 6 instruments to participate in simultaneously, so star sensor measuring system at least will have 6 transits.For setting up transit survey system, except 6 transits, also need have station meter, power supply and data cable, foot rest, control box, control and resolve software etc.This system, taking transit as instrument, is obtained the 3 d space coordinate value of impact point, can carry out to measurement data the measurement of geometric sense analysis and shape error.

In step (2), utilize any 2 transits mutually to take aim at mutually to set up the method for transit coordinate system to be:

(a) the telescope Focussing of two transits is arrived to position, infinite distance, thereby take aim at mutually crosshair, two parallel to each other completing mutually of transit collimation axis are taken aim at;

(b) taking any transit in 6 transits as survey station 1, survey station 1 is true origin, any transit of choosing in all the other 5 transits is survey station 2, the line of survey station 1 and survey station 2 in the horizontal direction be projected as X-axis, the vertical of crossing survey station 1 is Z axis, determine Y-axis with right-hand rule, form transit coordinate system.

For example: two transit A and B, taking A as true origin, AB line in the horizontal direction be projected as X-axis, the vertical of crossing A is Z axis, determines Y-axis with right-hand rule, forms thus transit coordinate system.

As shown in Figure 4, A, B takes aim at mutually and the observed reading (horizontal direction value, zenith distance) of difference observed object P is respectively α _aB, γ _bA, α _bA, γ _aPα _aP, α _bP.Make horizontal angle A, B is: A=γ _aB-γ _aP, B=γ _bP-γ _bA, the three-dimensional coordinate that P is ordered is:

$\left\{\begin{array}{c}X=\frac{\sin B\cos A}{\sin (A+B)}b\\ Y=\frac{\sin B\sin A}{\sin (A+B)}b\\ Z=\frac{1}{2}[\frac{\sin \mathrm{Bctg}{\mathrm{\α}}_{\mathrm{AP}}+\sin \mathrm{Actg}{\mathrm{\α}}_{\mathrm{BP}}}{\sin (A+B)}b+h]\end{array}\right.---\left(1\right)$

B is base length (i.e. horizontal range between two instrument A and B) in formula (1); H is the discrepancy in elevation of two instruments, meets: $h=\frac{1}{2}(\mathrm{ctg}{\mathrm{\α}}_{\mathrm{AB}}-\mathrm{ctg}{\mathrm{\α}}_{\mathrm{BA}})b$

If horizontal angle surveying precision is m _β, the planar point bit error that P is ordered is so:

$m_P=\frac{L}{{\sin }^2\mathrm{\γ}}\sqrt{{\sin }^{2}A+{\sin }^{2}B}\left(\frac{m_{\mathrm{\β}}}{\mathrm{\ρ}}\right)---\left(2\right)$

If vertical angle measuring accuracy is similarly m _β, P point height error is so:

$m_{Z_P}=\sqrt{\frac{S^2}{{\cos }^4{\mathrm{\α}}_{\mathrm{AP}}}\left(\frac{m_{\mathrm{\β}}}{\mathrm{\ρ}}\right)+Z^2{\left(\frac{m_s}{S}\right)}^{2}B}---\left(3\right)$

The flat distance that in formula (3), S is AP, therefore the error in point measurement of spatial point P can be expressed as:

$M_P=\sqrt{{m_p}^2+{m_{Z_P}}^2}---\left(4\right)$

The method that obtains the relation of 3 relative transit coordinate systems of star sensor reference mirror in step (2) is: every two transits collimate to adjacent two minute surfaces of a star sensor reference mirror, obtain the X-axis vector sum Y-axis amount of adjacent two minute surfaces, as shown in Figure 5, utilize right-hand rule to obtain Z-axis direction amount, set up reference mirror coordinate system according to three axial vectors of reference mirror, the rotation matrix of reference mirror coordinate system and transit coordinate system is: $R=\left[\begin{array}{ccc}\cos {\mathrm{\α}}_x& \cos {\mathrm{\β}}_x& \cos {\mathrm{\γ}}_x\\ \cos {\mathrm{\α}}_y& \cos {\mathrm{\β}}_y& \cos {\mathrm{\γ}}_y\\ \cos {\mathrm{\α}}_z& \cos {\mathrm{\β}}_z& \cos {\mathrm{\γ}}_z\end{array}\right],$

Wherein:

α _xfor the X-axis of reference mirror coordinate system is with respect to the angle of transit coordinate system X-axis,

β _xfor the X-axis of reference mirror coordinate system is with respect to the angle of transit coordinate system Y-axis,

γ _xfor the X-axis of reference mirror coordinate system is with respect to the angle of transit coordinate system Z axis,

α _yfor the Y-axis of reference mirror coordinate system is with respect to the angle of transit coordinate system X-axis,

β _yfor the Y-axis of reference mirror coordinate system is with respect to the angle of transit coordinate system Y-axis,

γ _yfor the Y-axis of reference mirror coordinate system is with respect to the angle of transit coordinate system Z axis,

α _zfor the Z axis of reference mirror coordinate system is with respect to the angle of transit coordinate system X-axis,

β _zfor the Z axis of reference mirror coordinate system is with respect to the angle of transit coordinate system Y-axis,

γ _zfor the Z axis of reference mirror coordinate system is with respect to the angle of transit coordinate system Z axis.

(3) utilize the relation between 3 star sensor reference mirror that transformational relation between single star sensor coordinate system and this star sensor reference mirror that step (1) obtains and step (2) obtain to obtain the relation between three star sensor coordinate systems, thereby realize the demarcation that star sensor probe assembly optical axis is pointed to.

The content not being described in detail in instructions of the present invention belongs to those skilled in the art's known technology.

Claims (3)

1. a star sensor probe assembly optical axis orientation calibrating method, is characterized in that step is as follows:

(1) before the combination of star sensor probe assembly is installed, utilize photogrammetric survey method to demarcate respectively 3 of star sensor probe assembly star sensors, obtain the transformational relation between the quick device reference mirror of each star sensor coordinate system and this star, the star sensor probe of having demarcated is combined to installation;

(2) set up the transit survey system that comprises at least 6 transits, first utilize any 2 transits mutually to take aim at mutually and set up transit coordinate system, then utilize every two transits to collimate and obtain the relation of 3 relative transit coordinate systems of star sensor reference mirror the reference mirror of one of them star sensor, finally obtain 3 relations between star sensor reference mirror according to the relation of 3 relative transit coordinate systems of star sensor reference mirror;

(3) utilize the relation between 3 star sensor reference mirror that transformational relation between single star sensor coordinate system and this star sensor reference mirror that step (1) obtains and step (2) obtain to obtain the relation between three star sensor coordinate systems, thereby realize the demarcation that star sensor probe assembly optical axis is pointed to;

The method that obtains the relation of 3 relative transit coordinate systems of star sensor reference mirror in described step (2) is: every two transits collimate to adjacent two minute surfaces of a star sensor reference mirror, obtain the X-axis vector sum Y-axis amount of adjacent two minute surfaces, utilize right-hand rule to obtain Z-axis direction amount, set up reference mirror coordinate system according to three axial vectors of reference mirror, the rotation matrix of reference mirror coordinate system and transit coordinate system is:

$R=\left[\begin{array}{ccc}\cos {\mathrm{\α}}_x& \cos {\mathrm{\β}}_x& \cos {\mathrm{\γ}}_x\\ \cos {\mathrm{\α}}_y& \cos {\mathrm{\β}}_y& \cos {\mathrm{\γ}}_y\\ \cos {\mathrm{\α}}_z& \cos {\mathrm{\β}}_z& \cos {\mathrm{\γ}}_z\end{array}\right],$

Wherein:

α _xfor the X-axis of reference mirror coordinate system is with respect to the angle of transit coordinate system X-axis,

β _xfor the X-axis of reference mirror coordinate system is with respect to the angle of transit coordinate system Y-axis,

γ _xfor the X-axis of reference mirror coordinate system is with respect to the angle of transit coordinate system Z axis,

α _yfor the Y-axis of reference mirror coordinate system is with respect to the angle of transit coordinate system X-axis,

β _yfor the Y-axis of reference mirror coordinate system is with respect to the angle of transit coordinate system Y-axis,

γ _yfor the Y-axis of reference mirror coordinate system is with respect to the angle of transit coordinate system Z axis,

α _zfor the Z axis of reference mirror coordinate system is with respect to the angle of transit coordinate system X-axis,

β _zfor the Z axis of reference mirror coordinate system is with respect to the angle of transit coordinate system Y-axis,

γ _zfor the Z axis of reference mirror coordinate system is with respect to the angle of transit coordinate system Z axis.

2. a kind of star sensor probe assembly optical axis orientation calibrating method according to claim 1, is characterized in that: the implementation method of described step (1) is:

(1) set up the coordinate system of transit survey system, the reference mirror to each star sensor under transit survey system coordinate system collimates, and obtains the relative parameter of star sensor reference mirror under transit survey system coordinate system;

(2) utilize transit survey system to measure Calibration Field, obtain the three-dimensional coordinate of Calibration Field mark under transit survey system coordinate system;

(3) utilize common point conversion, obtain the transformational relation of Calibration Field coordinate system and transit survey system coordinate system, thereby obtain the relation of star sensor reference mirror and Calibration Field coordinate system;

(4) utilize separate unit star sensor to the Calibration Field imaging of taking pictures, utilize resection method to obtain the relation of star sensor coordinate system and Calibration Field coordinate system, obtain the relation between separate unit star sensor coordinate system and this star sensor reference mirror.

3. a kind of star sensor probe assembly optical axis orientation calibrating method according to claim 1, is characterized in that: in described step (2), utilize any 2 transits mutually to take aim at mutually to set up the method for transit coordinate system to be:

(1) the telescope Focussing of two transits is arrived to position, infinite distance, thereby take aim at mutually crosshair, two parallel to each other completing mutually of transit collimation axis are taken aim at;

(2) taking any transit in 6 transits as survey station 1, survey station 1 is true origin, any transit of choosing in all the other 5 transits is survey station 2, the line of survey station 1 and survey station 2 in the horizontal direction be projected as X-axis, the vertical of crossing survey station 1 is Z axis, determine Y-axis with right-hand rule, form transit coordinate system.