A method for solving fixed image rotation of telescope based on three-point coordinates

Abstract

The present invention discloses a method for solving the fixed image rotation of a telescope based on three-point coordinates. The specific steps are as follows: first, record the current target miss amount coordinate O and the target miss amount coordinates P and Q after adding control amounts to the two directions of the fast mirror respectively. Then, the coordinates O and P are used to determine the quadrant position of the direction of the X direction and the fixed image rotation angle, and the coordinates O, P, and Q are used to determine the polarities A1 and A2 of the miss amount error, and then the polarities K1 and K4 of the rotation matrix are determined by judging the positive and negative signs of the cosine values ​​after the image rotation angle is converted into radians. Finally, a control amount is added to one of the directions to judge the direction of its own direction and the influence on the other direction, and at the same time, the polarities K2 and K3 of the rotation matrix are determined in combination with the sine value after the image rotation angle is converted into radians, thereby obtaining a complete image rotation solution formula. The method of the present invention has fast calculation speed, is easy to implement, and has stable performance. The fixed image rotation angle can be obtained only through three-point coordinates, and all polarities of the miss amount error and the rotation matrix can be derived.

Description

Technical Field

[0001] The invention relates to the technical field of ground-based telescope tracking control, and in particular to a method for resolving fixed image rotation of a telescope based on three-point coordinates. Background Art

[0002] In the telescope precision tracking control system, due to the needs of system design, the fast mirror must be installed in a certain direction, which may be inconsistent with the installation direction of the detector. In this way, the image in the detector will produce a fixed rotation, which brings difficulties to tracking control.

[0003] The current solution method for the image-rotation relationship is: align a fixed, imageable point target in the detector, then change the polarity of the rotation matrix, perform a closed-loop operation, and try them one by one until the closed-loop is successful. In actual work, this increases the workload of the debugging personnel, makes the work efficiency very low, and cannot achieve fast solution.

[0004] With the development of technology in the field of tracking control, the requirements for equipment debugging time are becoming increasingly stringent, so higher requirements are placed on image rotation solution. Therefore, a more convenient, faster solution method with low requirements on the environment and auxiliary conditions is needed. The existing methods are difficult to meet the requirements in terms of both efficiency and convenience. Summary of the invention

[0005] The object of the present invention is to provide a method for solving the fixed image rotation of a telescope based on three-point coordinates, so as to realize the closed-loop television tracking of the telescope.

[0006] The technical solution adopted by the present invention is: a method for solving the fixed image rotation of a telescope based on three-point coordinates, comprising the following steps:

[0007] Step (1), providing an imageable point target in any direction of the telescope, and recording the coordinates of the miss distance in the X and Y directions as O(x, y);

[0008] Step (2), constructing a plane rectangular coordinate system with coordinate O(x, y) as the origin;

[0009] Step (3), increase the X direction control amount of the fast reflex mirror, record the X and Y direction miss amount coordinates as P(x, y), and increase the same control amount in the opposite direction of X open loop to return it to the origin position;

[0010] Step (4), increase the Y direction control amount of the fast reflex mirror, and record the X and Y direction miss amount coordinates as Q (x, y);

[0011] Step (5), using the coordinates O(x, y) and the coordinates P(x, y) to determine the quadrant position of the X-direction direction;

[0012] Step (6), calculating the fixed image rotation angle α;

[0013] Step (7), using coordinates O(x, y), P(x, y), Q(x, y), respectively determine polarities A1 and A2 of miss distance errors FTV_Errx and FTV_Erry;

[0014] Step (8), determining the polarity K1, K4 of the rotation matrix by judging the positive and negative signs of the cosine value after the image rotation angle is converted into radians;

[0015] Step (9), judging by the coordinates O(x, y), P(x, y), and Q(x, y) whether the miss amount in the X or Y direction is offset to the left or right or upward or downward when the control amount is increased in the X or Y direction;

[0016] Step (10), judging by the coordinates O(x, y), P(x, y), and Q(x, y) whether the miss amount in the Y or X direction is shifted upward or downward or leftward or rightward when the control amount in the X or Y direction is increased;

[0017] Step (11), through the above step (9) and the above step (10) and the positive and negative signs of the sine values ​​after the image rotation angle is converted into radians, the polarities K2 and K3 of the rotation matrix are determined.

[0018] Furthermore, in step (1), for a point target, if it is in the outer field, it is provided by the target point, and if it is in the inner field, it is provided by a collimator.

[0019] Furthermore, in step (5), the quadrant position of the X-direction direction may appear in all four quadrants.

[0020] Furthermore, in step (6), all rotations are defined as counterclockwise rotations in the X direction, where PI is the circumference of a circle, RTOD is the equivalent of the rotation angle in radians,

[0021] 1) When the X movement direction is the first quadrant:

[0022] α=(arctan(fabs(1.0*(Py_-Oy_))))*RTOD

[0023] 2) When X moves in the second quadrant:

[0024] α=(PI-arctan(fabs(1.0*(Py_-Oy_))))*RTOD

[0025] 3) When the X movement direction is the third quadrant:

[0026] α=(PI+arctan(fabs(1.0*(Py_-Oy_))))*RTOD

[0027] 4) When the X movement direction is the fourth quadrant:

[0028] α=(PI*2-arctan(fabs(1.0*(Py_-Oy_))))*RTOD

[0029] Furthermore, in step (7), the off-target error is specified as a positive number. If Ox is greater than Px, the polarity of A1 is positive, otherwise the polarity of A1 is negative; if Oy is greater than Qy, the polarity of A2 is positive, otherwise the polarity of A2 is negative.

[0030] Furthermore, in step (8), if the cosine value of the image rotation angle after being converted into radians is a positive number, then the polarities of K1 and K4 are both positive, otherwise the polarities of K1 and K4 are both negative.

[0031] Furthermore, in step (9), if Py is greater than Oy, it means that the miss distance in the Y direction is offset downward, otherwise it is offset upward; if Qx is greater than Ox, the miss distance in the X direction is offset to the right, otherwise it is offset to the left.

[0032] Further, in step (10), if Px is greater than Ox, the miss distance in the X direction is shifted to the right, otherwise it is shifted to the left; if Qy is greater than Oy, the miss distance in the Y direction is shifted downward, otherwise it is shifted upward.

[0033] Further, in step (11), when the sine value of the image rotation angle is positive, and the X or Y motion direction is consistent with the X or Y offset direction when the Y or X motion is in progress, then the polarities K2 and K3 of the rotation matrix are both negative, otherwise the polarities K2 and K3 are both positive; when the sine value of the image rotation angle is negative, and the X or Y motion direction is consistent with the X or Y offset direction when the Y or X motion is in progress, then the polarities K2 and K3 of the rotation matrix are both positive, otherwise the polarities K2 and K3 are both negative.

[0034] The advantages of the present invention compared with the prior art are:

[0035] (1) The present invention can obtain the image rotation angle, the miss error and all polarities of the rotation matrix only through three-point coordinates, and the calculation process is simple and easy to implement.

[0036] (2) The present invention can solve the time-consuming and labor-intensive problem of multiple manual calibrations by debugging personnel, thereby simplifying and facilitating the debugging work.

[0037] (3) The present invention can solve the image rotation angle in any installation direction of the fast reflection mirror, with few restrictions on the required conditions, strong adaptability and fast solving speed. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 The present invention is a processing flow chart of a method for solving a fixed image rotation of a telescope based on three-point coordinates.

[0039] Figure 2 The following is a schematic diagram of eight fixed image rotations that exist in actual systems. Among them, a, b, c, and d represent conventional rotation relationships, and e, f, g, and h represent rotation relationships with inverted mirrors in the Y direction.

[0040] Figure 3 It is the complete derotation formula obtained by the present invention. Wherein, Sin_FTV and Cos_FTV respectively represent the sine value and cosine value of the image rotation angle after being converted into radians, DTOR represents the equivalent of the angle converted into radians, FTV_Errx and FTV_ErrY respectively represent the errors of the miss amount X and the miss amount Y, A1 and A2 respectively represent the polarities of the miss amount X and the miss amount Y errors, ep_x and ep_y respectively represent the azimuth and pitch errors corresponding to the telescope frame after rotation, and K1, K2, K3, and K4 represent the four polarities of the rotation matrix. DETAILED DESCRIPTION

[0041] The specific implementation modes of the present invention are described in detail below with reference to the accompanying drawings.

[0042] The specific process of the telescope fixed image rotation solution method based on three-point coordinates described in the present invention is as shown in the attached figure. Figure 1 As shown, the specific steps are as follows:

[0043] Step (1), providing an imageable point target in any direction of the telescope, if it is in the outer field, it is provided by the target point, if it is in the inner field, it is provided by the collimator, and then recording the X and Y direction miss distance coordinates as O(x, y);

[0044] Step (2), constructing a plane rectangular coordinate system with coordinate O(x, y) as the origin;

[0045] Step (3), increase the X direction control amount of the fast reflex mirror, record the X and Y direction miss amount coordinates as P(x, y), and increase the same control amount in the opposite direction of X open loop to return it to the origin position;

[0046] Step (4), increase the Y direction control amount of the fast reflex mirror, and record the X and Y direction miss amount coordinates as Q (x, y);

[0047] Step (5), using the coordinates O(x, y) and P(x, y) to determine the quadrant where the X-direction is located, which may appear in all four quadrants;

[0048] 1) If Px_-Ox_>0 and Py_-Oy_<=0, the X direction is the first quadrant.

[0049] 2) If Px_-Ox_<=0 and Py_-Oy_<0, the X direction is in the second quadrant.

[0050] 3) If Px_-Ox_<0 and Py_-Oy_>=0, the X direction is in the third quadrant.

[0051] 4) If Px_-Ox_>=0 and Py_-Oy_>0, the X direction is the fourth quadrant.

[0052] Step (6), calculate the fixed image rotation angle α, and stipulate that all rotations are counterclockwise rotations in the X direction, where PI is pi and RTOD is the equivalent of the rotation angle in radians;

[0053] 1) When the X movement direction is the first quadrant:

[0054] α=(arctan(fabs(1.0*(Py_-Oy_))))*RTOD

[0055] 2) When X moves in the second quadrant:

[0056] α=(PI-arctan(fabs(1.0*(Py_-Oy_))))*RTOD

[0057] 3) When the X movement direction is the third quadrant:

[0058] α=(PI+arctan(fabs(1.0*(Py_-Oy_))))*RTOD

[0059] 4) When the X movement direction is the fourth quadrant:

[0060] α=(PI*2-arctan(fabs(1.0*(Py_-Oy_))))*RTOD

[0061] Step (7), using the coordinates O(x, y), P(x, y), Q(x, y) to respectively determine the polarities A1 and A2 of the miss amount errors FTV_Errx and FTV_Erry, stipulating that the miss amount errors are positive numbers, if Ox is greater than Px, then the polarity of A1 is positive, otherwise the polarity of A1 is negative; if Oy is greater than Qy, then the polarity of A2 is positive, otherwise the polarity of A2 is negative;

[0062] Step (8), if the cosine value after the image rotation angle is converted into radians is a positive number, then the polarities of K1 and K4 are both positive, otherwise the polarities of K1 and K4 are both negative;

[0063] Step (9), judging by the coordinates O(x,y), P(x,y), and Q(x,y) when the control amount is increased in the X or Y direction, if Py is greater than Oy, it means that the miss amount in the Y direction is offset downward, otherwise it is offset upward; if Qx is greater than Ox, the miss amount in the X direction is offset to the right, otherwise it is offset to the left;

[0064] Step (10), judging by the coordinates O(x,y), P(x,y), and Q(x,y) when the control amount is increased in the X or Y direction, if Px is greater than Ox, the miss amount in the X direction is offset to the right, otherwise it is offset to the left; if Qy is greater than Oy, the miss amount in the Y direction is offset downward, otherwise it is offset upward;

[0065] Step (11), when the sine value of the image rotation angle is positive, and the X movement direction is consistent with the offset direction of X during Y movement, or the Y movement direction is consistent with the offset direction of Y during X movement, then the polarities K2 and K3 of the rotation matrix are both negative, otherwise the polarities K2 and K3 are both positive; when the sine value of the image rotation angle is negative, and the X movement direction is consistent with the offset direction of X during Y movement, and the Y movement direction is consistent with the offset direction of Y during X movement, then the polarities K2 and K3 of the rotation matrix are both positive, otherwise the polarities K2 and K3 are both negative;

[0066] The method of the present invention has fast calculation speed, is easy to implement and has stable performance. The fixed image rotation angle can be obtained only through three-point coordinates, and the miss amount error and all polarities of the rotation matrix can be derived.

[0067] The above is only a specific implementation of the present invention, but the protection scope of the present invention is not limited thereto. Any person familiar with the technology can understand and think of any changes or substitutions within the technical scope disclosed by the present invention, which should be included in the scope of the present invention. The contents not described in detail in this specification belong to the prior art known to professional and technical personnel in this field.

Claims

1. A method for solving fixed image rotation of a telescope based on three-point coordinates, characterized in that: The method has the following steps: Step (1): Provide an imageable point target in any direction of the telescope and record , The coordinates of the direction miss distance are ; Step (2), with coordinates Construct a plane rectangular coordinate system for the origin; Step (3): Add a fast-reflecting mirror Direction control amount, record this time , The coordinates of the direction miss distance are , and give In the opposite direction, the same control amount is added in the open loop to return it to the origin position; Step (4): Add a fast-reflecting mirror Direction control amount, record this time , The coordinates of the direction miss distance are ; Step (5): Using coordinates With coordinates Sure The quadrant in which the direction is located; Step (6): Calculate the fixed image rotation angle ; Step (7), using coordinates , , Determine the miss error , Polarity , ; Step (8), determining the polarity K1, K4 of the rotation matrix by judging the positive and negative signs of the cosine value after the image rotation angle is converted into radians; Step (9), through the coordinates , , When judging Or when the control amount is increased in the Y direction, Or the miss distance in the Y direction is offset to the left or right or upward or downward; in step (9), if Greater than , then it means The direction miss amount is offset downward, otherwise it is offset upward; if Greater than ,but The direction miss amount is offset to the right, otherwise it is offset to the left; Step (10), through the coordinates , , When judging Or when the control amount is increased in the Y direction, Or the miss distance in the X direction is upward or downward or left or right; in step (10), if Greater than ,but The direction miss amount shifts to the right, otherwise it shifts to the left; if Greater than ,but The direction miss amount is offset downward, otherwise it is offset upward; Step (11), determining the polarity of the rotation matrix by the above steps (9) and (10) and the positive and negative signs of the sine values ​​after the image rotation angle is converted into radians , .

2. The method for calculating fixed image rotation of a telescope based on three-point coordinates according to claim 1, characterized in that: In step (1), for a point target, if it is in the outer field, it is provided by the target point; if it is in the inner field, it is provided by the collimator.

3. The method for solving the fixed image rotation of a telescope based on three-point coordinates according to claim 1, characterized in that: In step (5), for The direction of the trend can occur in any of the four quadrants.

4. The method for calculating fixed image rotation of a telescope based on three-point coordinates according to claim 1, characterized in that: In step (6), all rotations are defined as The direction of rotation is counterclockwise, where is the circumference of a circle, is the equivalent of radians to angles, 1) When the X movement direction is the first quadrant: 2) When X moves in the second quadrant: 3) When the X movement direction is the third quadrant: 4) When the X movement direction is the fourth quadrant: 。 5. The method for solving the fixed image rotation of a telescope based on three-point coordinates according to claim 1, characterized in that: In step (7), the miss error is defined as a positive number. Greater than ,but Polarity is positive, otherwise The polarity is negative; if Greater than ,but Polarity is positive, otherwise The polarity is negative.

6. The method for solving the fixed image rotation of a telescope based on three-point coordinates according to claim 1, characterized in that: In step (8), if the cosine value of the image rotation angle after being converted into radians is positive, then the polarities of K1 and K4 are both positive, otherwise the polarities of K1 and K4 are both negative.

7. The method for solving the fixed image rotation of a telescope based on three-point coordinates according to claim 1, characterized in that: In step (11), when the image rotation angle is converted to an angle whose sine value is positive, and Or Y direction of motion and Or X movement Or when the Y offset direction is the same, the polarity of the rotation matrix , All are negative, otherwise , The polarity is positive; when the sine of the image rotation angle is negative, and Or Y direction of motion and Or X movement Or when the Y offset direction is the same, the polarity of the rotation matrix , All are positive, otherwise , The polarity is negative.

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