CN103886208A - High-resolution optical satellite maneuvering imaging drift angle correction method - Google Patents

Abstract

The invention discloses a high-resolution optical satellite maneuvering imaging drift angle correction method. A drift angle correction model under a maneuvering imaging mode is set up according to a satellite attitude maneuver scheme, a method for calculating a drift angle is derived based on the satellite position and ground point position coordinates, and a scheme for installing a drift angle correction device at the focal plane position is provided. Thus, a satellite can have the imaging capacity on a target strip deviating from the flying direction, the observation range and the observation efficiency of the satellite are greatly improved, and meanwhile, the satellite can have the dynamic pushing and blooming imaging capacity in the vertical direction of a sub-satellite point. Large-width imaging of a sub-satellite point area is achieved in a multi-strip splicing manner, and the requirement for the TDICCD camera width is lowered.

Description

A Method of Correcting the Drift Angle of High Resolution Optical Satellite Maneuvering Imaging

technical field

The invention belongs to the field of optical remote sensing satellite imaging, and relates to a method for correcting a deflection angle of a high-resolution optical satellite mobile imaging equipped with a TDICCD camera.

Background technique

TDICCD is based on multiple exposures of the same target to achieve time-delay integration, which greatly enhances light energy collection and improves the signal-to-noise ratio, so it is widely used in high-resolution optical remote sensing satellites. But at the same time, due to the special working method of TDICCD, each pixel on the same column is required to integrate the exposure of the same target. The basic premise of its normal operation is that the transfer of photogenerated charge packets is synchronized with the movement of the image on the focal plane. Any matching errors will result in blurred images.

At present, most satellites use attitude maneuvering in advance to make the optical axis of the camera point to the target area stably, and then realize the push-broom imaging of the target by the TDICCD camera through satellite movement (see Figure 1). In this imaging mode, the attitude of the satellite remains unchanged. The object-image relationship of the TDICCD camera is stable, and the main source of image blur is that the satellite flight direction caused by the earth's rotation is inconsistent with the actual imaging direction of the TDICCD camera. The angle between the two is the drift angle, which will cause the camera to produce The lateral image motion of the image affects the image quality of the camera. Therefore, adjusting the drift angle is an important task in the image motion compensation system of the TDICCD camera.

In recent years, aerospace optical remote sensing technology has developed rapidly, and the rapid attitude maneuverability of satellites has been greatly improved. High-resolution agile satellites with flexible attitude maneuverability and high ground resolution have emerged. If the traditional observation mode shown in Figure 1 is used to detect the target For observation, for the target strip area with a certain angle with the flight direction, if the satellite TDICCD camera width is limited, and one push-broom cannot cover the whole picture of the target, it is necessary to plan the mission and splicing multiple strips of different orbits. Comprehensive observation of the target area can be achieved.

In view of the characteristics of the agile satellite's powerful attitude maneuverability, people began to study a new working mode of TDICCD imaging in the process of real-time adjustment of the attitude to realize the real-time pointing of the target strip with a certain angle with the flight direction—maneuvering imaging (see appendix figure 2). In this mode, because the satellite attitude changes with time, the source of the drift angle is not only the influence of the earth's rotation, but also the influence of the satellite attitude maneuver scheme. The calculation method and correction method of the drift angle in the satellite maneuver imaging mode is the key to realize the maneuver imaging. Necessary prerequisite.

There are no precedents for mobile imaging of existing satellites in orbit in China. There has been some research on the calculation method of the drift angle during the attitude change process, but no full-link research has been combined with the satellite mobile imaging mode. According to the current foreign data, the French Pleiades satellite and the American IKONOS satellite are agile satellites with fast maneuverability, which can flexibly realize strip splicing imaging, stereoscopic imaging, and regional point target imaging. According to the Pleiades satellite and IKONOS-2 According to the imaging mode given by the satellite, it is inferred that Pleiades and IKONOS-2 should also have mobile imaging capabilities, but there is no information available for the specific implementation method.

Contents of the invention

The technical problem solved by the present invention is: to overcome the deficiencies of the prior art, to provide a high-resolution optical satellite maneuvering imaging drift angle correction method, and to obtain the drift angle in the maneuvering imaging process for different attitude maneuvering schemes under the satellite maneuvering imaging mode According to the calculation model, it is proposed to install an image motion compensation device on the focal plane for real-time correction and compensation of the drift angle.

The technical solution of the present invention is: a method for correcting the deflection angle of high-resolution optical satellite mobile imaging, the steps are as follows:

1) According to the actual satellite parameters, establish the satellite model and the imaging model of the TDICCD camera on the satellite;

同时得到卫星实时位置坐标和地面点坐标所对应的时间t；2) According to the position of the target to be observed, determine the satellite attitude maneuver plan, generate satellite real-time attitude maneuver data, and obtain the satellite real-time position coordinates during the attitude maneuver process according to the satellite model obtained in step 1) and the TDICCD camera imaging model and the imaging ground point coordinates

At the same time, the time t corresponding to the satellite real-time position coordinates and the ground point coordinates is obtained;

对时间t求导，计算获得卫星速度矢量 ${\stackrel{\→}{V}}_s=(v_{x\_s},v_{y\_s},v_{z\_s}),$ 其中 $\begin{array}{c}{v}_{x\_s}=\frac{\mathrm{dSx}}{\mathrm{dt}};\\ v_{y\_s}=\frac{\mathrm{dSy}}{\mathrm{dt}};\\ v_{z\_s}=\frac{\mathrm{dSz}}{\mathrm{dt}};\end{array}$ 3) Use the satellite real-time position coordinates obtained in step 2)

Calculate the derivative of time t to obtain the satellite velocity vector ${\stackrel{\&Right\; Arrow;}{V}}_{\mathrm{the\; s}}=(v_{x\_\mathrm{the\; s}},v_{\mathrm{the\; y}\_\mathrm{the\; s}},v_{z\_\mathrm{the\; s}}),$ in $\begin{array}{c}{v}_{x\_\mathrm{the\; s}}=\frac{\mathrm{wxya}}{\mathrm{dt}};\\ v_{\mathrm{the\; y}\_\mathrm{the\; s}}=\frac{\mathrm{wxya}}{\mathrm{dt}};\\ v_{z\_\mathrm{the\; s}}=\frac{\mathrm{wxya}}{\mathrm{dt}};\end{array}$

对时间t求导，计算获得摄影点地速矢量 ${\stackrel{\→}{V}}_g=(v_{x\_g},v_{y\_g},v_{z\_g}),$ 其中 $\begin{array}{c}{v}_{x\_g}=\frac{\mathrm{dGx}}{\mathrm{dt}};\\ v_{y\_g}=\frac{\mathrm{dGy}}{\mathrm{dt}};\\ v_{z\_g}=\frac{\mathrm{dGz}}{\mathrm{dt}};\end{array}$ 4) The ground point coordinates obtained in step 2)

Deriving time t to calculate the ground speed vector of the photography point ${\stackrel{\&Right\; Arrow;}{V}}_g=(v_{x\_g},v_{\mathrm{the\; y}\_g},v_{z\_g}),$ in $\begin{array}{c}{v}_{x\_g}=\frac{\mathrm{wxya}}{\mathrm{dt}};\\ v_{\mathrm{the\; y}\_g}=\frac{\mathrm{wxya}}{\mathrm{dt}};\\ v_{z\_g}=\frac{\mathrm{gz}}{\mathrm{dt}};\end{array}$

与地速矢量

在TDICCD相机焦平面上投影矢量之间的夹角θ(t)，即偏流角θ(t)；5) Calculate the satellite velocity vector

and ground speed vector

The angle θ(t) between the projection vectors on the focal plane of the TDICCD camera is the bias angle θ(t);

51) Calculate and obtain the projection vector of the satellite velocity vector on the focal plane

$\stackrel{\→}{F}=\frac{{\stackrel{\→}{P}}_s-{\stackrel{\→}{P}}_g}{|{\stackrel{\→}{P}}_s-{\stackrel{\→}{P}}_g|}=\frac{(\mathrm{Sx},\mathrm{Sy},\mathrm{Sz})-(\mathrm{Gx},\mathrm{Gy},\mathrm{Gz})}{|(\mathrm{Sx},\mathrm{Sy},\mathrm{Sz})-(\mathrm{Gx},\mathrm{Gy},\mathrm{Gz})}=\frac{((\mathrm{Sx}-\mathrm{Gx}),(\mathrm{Sy}-G_y),(\mathrm{Sz}-G_z))}{\sqrt{{(\mathrm{Sx}-\mathrm{Gx})}^2+{(\mathrm{Sy}-\mathrm{Gy})}^2+{(\mathrm{Sz}-\mathrm{Gz})}^2}},$ 其中为

之间的夹角；52) Calculate the projection vector of the ground speed vector on the focal plane

$\stackrel{\&Right\; Arrow;}{f}=\frac{{\stackrel{\&Right\; Arrow;}{P}}_{\mathrm{the\; s}}-{\stackrel{\&Right\; Arrow;}{P}}_g}{|{\stackrel{\&Right\; Arrow;}{P}}_{\mathrm{the\; s}}-{\stackrel{\&Right\; Arrow;}{P}}_g|}=\frac{(\mathrm{S\; x},\mathrm{Sy},\mathrm{Sz})-(\mathrm{Gx},\mathrm{Gy},\mathrm{Gz})}{|(\mathrm{S\; x},\mathrm{Sy},\mathrm{Sz})-(\mathrm{Gx},\mathrm{Gy},\mathrm{Gz})}=\frac{((\mathrm{S\; x}-\mathrm{Gx}),(\mathrm{Sy}-G_{\mathrm{the\; y}}),(\mathrm{Sz}-G_z))}{\sqrt{{(\mathrm{S\; x}-\mathrm{Gx})}^2+{(\mathrm{Sy}-\mathrm{Gy})}^2+{(\mathrm{Sz}-\mathrm{Gz})}^2}},$ in for

the angle between

53) Calculate and obtain the drift angle $\mathrm{\θ}\left(t\right)=\arcsin d\left(\frac{|{\stackrel{\&Right\; Arrow;}{V}}_{\mathrm{the\; s}\_c}\×{\stackrel{\&Right\; Arrow;}{V}}_{g\_c}|}{\left|{\stackrel{\&Right\; Arrow;}{V}}_{\mathrm{the\; s}\_c}\right|\×\left|{\stackrel{\&Right\; Arrow;}{V}}_{g\_c}\right|}\right);$

6) Under the satellite attitude maneuver scheme, a model of the drift angle θ(t) changing with time is established, and the focal plane drift angle compensation device is used to correct the drift angle θ(t) to 0 degrees in real time according to the model.

The advantage of the present invention compared with prior art is:

The invention models the high-resolution optical satellite maneuvering imaging mode equipped with the TDICCD camera, and simulates the implementation process of the new working mode of the satellite. Aiming at the satellite attitude maneuvering scheme, the drift angle correction model in maneuvering imaging mode is established, the method of calculating the drift angle based on the satellite position and the ground point position coordinates is deduced, and the scheme of installing the drift angle correction device at the focal plane position is proposed. It enables the satellite to have the ability to image target strips that deviate from the flight direction, greatly improving the observation range and observation efficiency of the satellite, and at the same time enables the satellite to have the ability of dynamic push-broom imaging along the vertical direction of the sub-satellite point, through the way of splicing multiple strips , to achieve a large width imaging of the sub-satellite point area, thereby reducing the requirement for the width of the TDICCD camera.

Description of drawings

Figure 1 is a schematic diagram of a general satellite imaging mode;

Figure 2 is a schematic diagram of the motorized imaging mode;

Fig. 3 is a composition diagram of the focal plane rotation compensation device;

Fig. 4 is the composition of the focal plane two-dimensional translation compensation device;

Fig. 5 is a flow chart of the method of the present invention.

Detailed ways

As shown in Figure 5, the present invention mainly comprises the following steps:

(1) Use the stk simulation software to establish the satellite scene and satellite model according to the actual satellite parameters, and use the sensor tools in the stk software to establish the TDICCD camera model under the satellite model to obtain the basic model of maneuvering imaging;

(2) Using matlab software, according to the target trajectory tracking requirements, determine the attitude maneuver scheme (transition sequence, attitude angular rate change, etc.), simulate and calculate the satellite attitude, obtain the real-time attitude data of the satellite at each moment, and at the same time calculate the satellite coordinate system , attitude angle sequence, loading time, etc., generate a satellite attitude data file (.a file) according to the attitude data format required by stk, and load it into the basic model established in step (1). The dynamic imaging process of the target trajectory to simulate.

The attitude data file format required by Stk is as follows:

data line content 1 Stk Version 2 BEGIN Attitude 3 NumberOfAttitudePoints 4 Blocking Factor 5 Interpolation Order

6 Central Body 7 ScenarioEpoch 8 CoordinateAxes 9 sequence 10 AttitudeTimeEulerAngles 11 Attitude data 12 END Attitude

以及相机视轴指向与地面交点坐标

同时输出实时位置坐标和地面点坐标对应的时间t；(3) Output the real-time position coordinates of the satellite during the dynamic imaging in step (2)

And the coordinates of the intersection point of the camera's boresight pointing to the ground

Simultaneously output the real-time position coordinates and the time t corresponding to the ground point coordinates;

Among them, the satellite position coordinates and the ground point coordinates adopt the coordinates in the geocentric fixed coordinate system. The origin O of the coordinate system is a fixed coordinate system that moves with the earth's spin and the center of the earth. Its x-axis points to the equatorial plane and the Greenwich meridian plane. Intersecting lines, the z-axis points to the north pole of the equator, and the y-axis forms a right-handed orthogonal system with the two axes of z and x.

(4) Deriving the satellite position coordinates with respect to time to obtain the satellite velocity vector

${\mathrm{<span\; class="notranslate">\; v</span>}}_{\mathrm{<span\; class="notranslate">\; x</span>}<span\; class="notranslate">\; \_</span>\mathrm{<span\; class="notranslate">\; the\; s</span>}}<span\; class="notranslate">\; =</span>\frac{\mathrm{<span\; class="notranslate">\; wxya</span>}}{\mathrm{<span\; class="notranslate">\; dt</span>}}<span\; class="notranslate">\; ;</span>$

${\mathrm{<span\; class="notranslate">\; v</span>}}_{\mathrm{<span\; class="notranslate">\; the\; y</span>}<span\; class="notranslate">\; \_</span>\mathrm{<span\; class="notranslate">\; the\; s</span>}}<span\; class="notranslate">\; =</span>\frac{\mathrm{<span\; class="notranslate">\; wxya</span>}}{\mathrm{<span\; class="notranslate">\; dt</span>}}<span\; class="notranslate">\; ;</span>$

${\mathrm{<span\; class="notranslate">\; v</span>}}_{\mathrm{<span\; class="notranslate">\; z</span>}<span\; class="notranslate">\; \_</span>\mathrm{<span\; class="notranslate">\; the\; s</span>}}<span\; class="notranslate">\; =</span>\frac{\mathrm{<span\; class="notranslate">\; wxya</span>}}{\mathrm{<span\; class="notranslate">\; dt</span>}}<span\; class="notranslate">\; ;</span>$

(5) Deriving the coordinates of the ground point with respect to time to obtain the ground speed vector of the photography point

${\mathrm{<span\; class="notranslate">\; v</span>}}_{\mathrm{<span\; class="notranslate">\; x</span>}<span\; class="notranslate">\; \_</span>\mathrm{<span\; class="notranslate">\; g</span>}}<span\; class="notranslate">\; =</span>\frac{\mathrm{<span\; class="notranslate">\; wxya</span>}}{\mathrm{<span\; class="notranslate">\; dt</span>}}<span\; class="notranslate">\; ;</span>$

${\mathrm{<span\; class="notranslate">\; v</span>}}_{\mathrm{<span\; class="notranslate">\; the\; y</span>}<span\; class="notranslate">\; \_</span>\mathrm{<span\; class="notranslate">\; g</span>}}<span\; class="notranslate">\; =</span>\frac{\mathrm{<span\; class="notranslate">\; wxya</span>}}{\mathrm{<span\; class="notranslate">\; dt</span>}}<span\; class="notranslate">\; ;</span>$

${\mathrm{<span\; class="notranslate">\; v</span>}}_{\mathrm{<span\; class="notranslate">\; z</span>}<span\; class="notranslate">\; \_</span>\mathrm{<span\; class="notranslate">\; g</span>}}<span\; class="notranslate">\; =</span>\frac{\mathrm{<span\; class="notranslate">\; gz</span>}}{\mathrm{<span\; class="notranslate">\; dt</span>}}<span\; class="notranslate">\; ;</span>$

与地速矢量

在TDICCD相机焦平面上投影矢量之间的夹角θ(t)，即为偏流角θ(t)；(6) Calculate the satellite velocity vector

and ground speed vector

The angle θ(t) between the projection vectors on the focal plane of the TDICCD camera is the bias angle θ(t);

a. The calculation method of the projection vector of the satellite push-broom velocity vector on the focal plane of the TDICCD camera:

Most TDICCD cameras are fixedly connected to the satellite body. The optical axis of the TDICCD camera is consistent with the z-axis, and the focal plane is perpendicular to the optical axis. Therefore, the projection vector of the satellite push-broom velocity vector on the focal plane is:

b. Calculation method of the projection vector of the ground speed vector on the focal plane

求已知矢量在该平面的投影矢量可按下述方法进行计算：According to the vector principle, the unit normal vector of a plane is known

Find a known vector The projection vector on this plane can be calculated as follows:

获得矢量到平面的距离b；

get vector the distance b to the plane;

获得模长为b的垂直于平面的向量；

Obtain a vector perpendicular to the plane with modulus length b;

即为

在平面上的投影矢量。

that is

Projection vector on a plane.

According to the above, the calculation method of the projection vector of the ground speed vector on the focal plane is as follows:

The focal plane unit normal vector can be calculated by the following formula:

$\stackrel{<span\; class="notranslate">\; \&Right\; Arrow;</span>}{\mathrm{<span\; class="notranslate">\; f</span>}}<span\; class="notranslate">\; =</span>\frac{{\stackrel{<span\; class="notranslate">\; \&Right\; Arrow;</span>}{\mathrm{<span\; class="notranslate">\; P</span>}}}_{\mathrm{<span\; class="notranslate">\; the\; s</span>}}<span\; class="notranslate">\; -</span>{\stackrel{<span\; class="notranslate">\; \&Right\; Arrow;</span>}{\mathrm{<span\; class="notranslate">\; P</span>}}}_{\mathrm{<span\; class="notranslate">\; g</span>}}}{<span\; class="notranslate">\; |</span>{\stackrel{<span\; class="notranslate">\; \&Right\; Arrow;</span>}{\mathrm{<span\; class="notranslate">\; P</span>}}}_{\mathrm{<span\; class="notranslate">\; the\; s</span>}}<span\; class="notranslate">\; -</span>{\stackrel{<span\; class="notranslate">\; \&Right\; Arrow;</span>}{\mathrm{<span\; class="notranslate">\; P</span>}}}_{\mathrm{<span\; class="notranslate">\; g</span>}}<span\; class="notranslate">\; |</span>}<span\; class="notranslate">\; =</span>\frac{<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; S\; x</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; Sy</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; Sz</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; Gx</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; Gy</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; Gz</span>}<span\; class="notranslate">\; )</span>}{<span\; class="notranslate">\; |</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; S\; x</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; Sy</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; Sz</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; Gx</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; Gy</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; Gz</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; |</span>}<span\; class="notranslate">\; =</span>\frac{<span\; class="notranslate">\; (</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; S\; x</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; Gx</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; ,</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; Sy</span>}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; G</span>}}_{\mathrm{<span\; class="notranslate">\; the\; y</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; ,</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; Sz</span>}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; G</span>}}_{\mathrm{<span\; class="notranslate">\; z</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; )</span>}{\sqrt{{<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; S\; x</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; Gx</span>}<span\; class="notranslate">\; )</span>}^{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; +</span>{<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; Sy</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; Gy</span>}<span\; class="notranslate">\; )</span>}^{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; +</span>{<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; Sz</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; Gz</span>}<span\; class="notranslate">\; )</span>}^{\mathrm{<span\; class="notranslate">\; 2</span>}}}}<span\; class="notranslate">\; ,</span>$

在焦平面投影为：but

Projected on the focal plane as:

${\stackrel{<span\; class="notranslate">\; \&Right\; Arrow;</span>}{\mathrm{<span\; class="notranslate">\; V</span>}}}_{\mathrm{<span\; class="notranslate">\; g</span>}<span\; class="notranslate">\; \_</span>\mathrm{<span\; class="notranslate">\; c</span>}}<span\; class="notranslate">\; =</span>{\stackrel{<span\; class="notranslate">\; \&Right\; Arrow;</span>}{\mathrm{<span\; class="notranslate">\; V</span>}}}_{\mathrm{<span\; class="notranslate">\; g</span>}}<span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>{\stackrel{<span\; class="notranslate">\; \&Right\; Arrow;</span>}{\mathrm{<span\; class="notranslate">\; V</span>}}}_{\mathrm{<span\; class="notranslate">\; g</span>}}<span\; class="notranslate">\; \&CenterDot;</span>\stackrel{<span\; class="notranslate">\; \&Right\; Arrow;</span>}{\mathrm{<span\; class="notranslate">\; f</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; \&times;</span>\stackrel{<span\; class="notranslate">\; \&Right\; Arrow;</span>}{\mathrm{<span\; class="notranslate">\; f</span>}}$

in:

为 ${\stackrel{\&RightArrow;}{V}}_g,\stackrel{\&RightArrow;}{F}$ 之间的夹角。

for ${\stackrel{\&Right\; Arrow;}{V}}_g,\stackrel{\&Right\; Arrow;}{f}$ angle between.

c. Calculation method of drift angle

和

求二者之间夹角可利用下式进行计算：known vector

and

The angle between the two can be calculated using the following formula:

$<span\; class="notranslate">\; |</span>{\stackrel{<span\; class="notranslate">\; \&Right\; Arrow;</span>}{\mathrm{<span\; class="notranslate">\; V</span>}}}_{\mathrm{<span\; class="notranslate">\; the\; s</span>}<span\; class="notranslate">\; \_</span>\mathrm{<span\; class="notranslate">\; c</span>}}<span\; class="notranslate">\; \&times;</span>{\stackrel{<span\; class="notranslate">\; \&Right\; Arrow;</span>}{\mathrm{<span\; class="notranslate">\; V</span>}}}_{\mathrm{<span\; class="notranslate">\; g</span>}<span\; class="notranslate">\; \_</span>\mathrm{<span\; class="notranslate">\; c</span>}}<span\; class="notranslate">\; |</span><span\; class="notranslate">\; =</span><span\; class="notranslate">\; |</span>{\stackrel{<span\; class="notranslate">\; \&Right\; Arrow;</span>}{\mathrm{<span\; class="notranslate">\; V</span>}}}_{\mathrm{<span\; class="notranslate">\; the\; s</span>}<span\; class="notranslate">\; \_</span>\mathrm{<span\; class="notranslate">\; c</span>}}<span\; class="notranslate">\; |</span><span\; class="notranslate">\; \&times;</span><span\; class="notranslate">\; |</span>{\stackrel{<span\; class="notranslate">\; \&Right\; Arrow;</span>}{\mathrm{<span\; class="notranslate">\; V</span>}}}_{\mathrm{<span\; class="notranslate">\; g</span>}<span\; class="notranslate">\; \_</span>\mathrm{<span\; class="notranslate">\; c</span>}}<span\; class="notranslate">\; |</span><span\; class="notranslate">\; \&times;</span>\mathrm{<span\; class="notranslate">\; sin</span>}\mathrm{<span\; class="notranslate">\; d</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; \&theta;</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; t</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; )</span><span\; class="notranslate">\; \&DoubleRightArrow;</span>$

$\mathrm{<span\; class="notranslate">\; \&theta;</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; t</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; arcsin</span>}\mathrm{<span\; class="notranslate">\; d</span>}<span\; class="notranslate">\; (</span>\frac{<span\; class="notranslate">\; |</span>{\stackrel{<span\; class="notranslate">\; \&Right\; Arrow;</span>}{\mathrm{<span\; class="notranslate">\; V</span>}}}_{\mathrm{<span\; class="notranslate">\; the\; s</span>}<span\; class="notranslate">\; \_</span>\mathrm{<span\; class="notranslate">\; c</span>}}<span\; class="notranslate">\; \&times;</span>{\stackrel{<span\; class="notranslate">\; \&Right\; Arrow;</span>}{\mathrm{<span\; class="notranslate">\; V</span>}}}_{\mathrm{<span\; class="notranslate">\; g</span>}<span\; class="notranslate">\; \_</span>\mathrm{<span\; class="notranslate">\; c</span>}}<span\; class="notranslate">\; |</span>}{<span\; class="notranslate">\; |</span>{\stackrel{<span\; class="notranslate">\; \&Right\; Arrow;</span>}{\mathrm{<span\; class="notranslate">\; V</span>}}}_{\mathrm{<span\; class="notranslate">\; the\; s</span>}<span\; class="notranslate">\; \_</span>\mathrm{<span\; class="notranslate">\; c</span>}}<span\; class="notranslate">\; |</span><span\; class="notranslate">\; \&times;</span><span\; class="notranslate">\; |</span>{\stackrel{<span\; class="notranslate">\; \&Right\; Arrow;</span>}{\mathrm{<span\; class="notranslate">\; V</span>}}}_{\mathrm{<span\; class="notranslate">\; g</span>}<span\; class="notranslate">\; \_</span>\mathrm{<span\; class="notranslate">\; c</span>}}<span\; class="notranslate">\; |</span>}<span\; class="notranslate">\; )</span>$

(7) According to the real-time value of the drift angle calculated in step (6) when the satellite attitude changes in real time, a drift angle compensation device is added on the focal plane, and two schemes as shown in Fig. 3 and Fig. 4 can be adopted.

For the scheme shown in Figure 3, the index requirements for the rotating motor are calculated according to the following formula:

Dynamic range: θ(t) _min ～θ(t) _max

Maximum Angular Rate:

For the scheme shown in Figure 4, the index requirements for the displacement adjustment component are calculated according to the following formula:

Linear array direction displacement adjustment components:

Dynamic range: L-L×cosd(θ(t))

Adjustment frequency: (L-L×cosd(θ(t)))/dt

Series direction displacement adjustment components:

Dynamic range: L-L×sind(θ(t))

Adjustment frequency: (L-L×sind(θ(t)))/dt

Among them, L is TDICCD half-width value.

The content that is not described in detail in the specification of the present invention belongs to the well-known technology of those skilled in the art.

Claims (1)

1. the motor-driven imaging drift angle of a high-resolution optical satellite modification method, is characterized in that step is as follows:

1), according to real satellite parameter, set up TDICCD camera imaging model on dummy satellite and satellite;

2) according to target location to be observed, determine the motor-driven scheme of the attitude of satellite, generate the real-time attitude maneuver data of satellite, and the dummy satellite obtaining according to step 1) and TDICCD camera imaging model, obtain attitude maneuver process Satellite real time position coordinate

and imaging topocentric coordinates

obtain the corresponding time t of satellite real time position coordinate and topocentric coordinates simultaneously;

3) by step 2) the satellite real time position coordinate that obtains to time t differentiate, calculate and obtain satellite velocity vector ${\stackrel{\&RightArrow;}{V}}_s=(v_{x\_s},v_{y\_s},v_{z\_s}),$ Wherein $\begin{array}{c}{v}_{x\_s}=\frac{\mathrm{dSx}}{\mathrm{dt}};\\ v_{y\_s}=\frac{\mathrm{dSy}}{\mathrm{dt}};\\ v_{z\_s}=\frac{\mathrm{dSz}}{\mathrm{dt}};\end{array}$

4) by step 2) topocentric coordinates that obtains

to time t differentiate, calculate and obtain photography point ground vector ${\stackrel{\&RightArrow;}{V}}_g=(v_{x\_g},v_{y\_g},v_{z\_g}),$ Wherein $\begin{array}{c}{v}_{x\_g}=\frac{\mathrm{dGx}}{\mathrm{dt}};\\ v_{y\_g}=\frac{\mathrm{dGy}}{\mathrm{dt}};\\ v_{z\_g}=\frac{\mathrm{dGz}}{\mathrm{dt}};\end{array}$

5) calculate satellite velocity vector

with ground vector angle theta (t) on TDICCD camera focal plane between projection vector, i.e. drift angle θ (t);

51) calculate and obtain the projection vector of satellite velocity vector in focal plane

52) calculate and obtain the projection vector of ground vector in focal plane

$\stackrel{\&RightArrow;}{F}=\frac{{\stackrel{\&RightArrow;}{P}}_s-{\stackrel{\&RightArrow;}{P}}_g}{|{\stackrel{\&RightArrow;}{P}}_s-{\stackrel{\&RightArrow;}{P}}_g|}=\frac{(\mathrm{Sx},\mathrm{Sy},\mathrm{Sz})-(\mathrm{Gx},\mathrm{Gy},\mathrm{Gz})}{|(\mathrm{Sx},\mathrm{Sy},\mathrm{Sz})-(\mathrm{Gx},\mathrm{Gy},\mathrm{Gz})}=\frac{((\mathrm{Sx}-\mathrm{Gx}),(\mathrm{Sy}-G_y),(\mathrm{Sz}-G_z))}{\sqrt{{(\mathrm{Sx}-\mathrm{Gx})}^2+{(\mathrm{Sy}-\mathrm{Gy})}^2+{(\mathrm{Sz}-\mathrm{Gz})}^2}},$ Wherein

for ${\stackrel{\&RightArrow;}{V}}_g,\stackrel{\&RightArrow;}{F}$ Between angle;

53) calculate and obtain drift angle $\mathrm{\&theta;}\left(t\right)=\arcsin d\left(\frac{|{\stackrel{\&RightArrow;}{V}}_{s\_c}\&times;{\stackrel{\&RightArrow;}{V}}_{g\_c}|}{\left|{\stackrel{\&RightArrow;}{V}}_{s\_c}\right|\&times;\left|{\stackrel{\&RightArrow;}{V}}_{g\_c}\right|}\right);$

6) under the motor-driven scheme of the attitude of satellite, set up drift angle θ (t) temporal evolution model, adopt focal plane drift angle compensation system that drift angle θ (t) is modified to 0 degree in real time according to this model.

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