JPH07291199A - Attitude control method for artificial satelite - Google Patents

Abstract

PURPOSE:To facilitate the processing for the on-satelite mounted sensor data and reduce deflection of the image of a stereoscopic pair sensor in the prepara tion of a map, etc., by setting the machine axial direction of a satelite as the vector direction, by calculating the quantity of the rotation of the earth and controlling the machine axial direction of the satelite to the advance direction of the satelite measured on the earth. CONSTITUTION:The difference between the timer information supplied from a timer device 5 and the Br passing time is counted by a data processing device 6, and the latitude of the satelite passing point is calculated, and the rotational speed of the earth at this latitude is calculated by the data processing device 6. Each deflection in the advance direction fixed on the satelite and the speed direction of the satelite in the coordinate system fixed on the earth is calculated by utilizing the attitude information supplied from an attitude gyro 4, rotational speed information of the earth, and the satelite speed information which is previously stored in the data processing device 6. A reaction wheel 7 is controlled so that the deflection information becomes zero and the attitude of the satelite is set so that the advance axis coincides with the advance direction of the satelite in the coordinate system fixed on the earth.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a satellite attitude control method.

[0002]

2. Description of the Related Art FIG. 24 is a block diagram showing an example of a conventional attitude control system for a polar orbit observation satellite. In the figure, 1 is a satellite structure, 2 is an earth sensor, 3 is a sun sensor, 4 is an attitude gyro. A device, 5 is a timer device, 6 is a data processing device, and 7 is a reaction wheel. In addition, FIG. 25 is a diagram for explaining the attitude of the satellite.
h is the earth, Orb is the orbit of the satellite, Sun is the sun, F
field is the field of view of the sun sensor.

In the above structure, the polar orbit satellite 1 captures the sun in the field of view of the sun sensor 3 by the sun sensor 3 at a position Br in which the sun can be seen from the shadow of the earth (referred to as the shade) with respect to the sun. At the same time, the earth sensor 2 captures the direction of the center of the earth. The reference axis of the attitude gyro device 4 is stored in the data processing device 6 with reference to these two signals. At the same time, it is acquired from the Br passage time timer device 5 and stored in the data processing device 6. When the machine axis is deviated from the preset direction, the attitude control reaction wheel 7 is used to change the direction of the attitude vector of the satellite in the inertial space to set the satellite axis direction to the predetermined direction.

In the above configuration, the polar orbit satellite 1 has a machine axis direction which is set in a coordinate system having the sun as the center and a line connecting the sun and the center of the earth as one axis, and maintains a constant direction with respect to the satellite orbit plane Orb. Was controlled as.

[0005]

Since the attitude control system is configured in the conventional polar orbit satellite as described above, the signal used for attitude control of the satellite does not include the term of the earth rotation, Looking at the attitude of the satellite above, the result is that the apparent traveling direction of the satellite does not match the direction of the aircraft axis due to the influence of the Earth's rotation.For example, when observing with an optical sensor, the screen is distorted was there.

The present invention has been made to solve the above problems and provides means for making the direction of the roll axis of the attitude axis of the satellite coincide with the traveling direction of the satellite as seen on the earth. It is a thing.

[0007]

In the attitude control system for polar orbit satellites according to the present invention, the means for calculating the amount of earth rotation, which has not been carried out by conventional satellites, is used to constantly change the satellite axis direction. It controls the traveling direction of the satellite as seen on the earth.

[0008]

In the attitude control system for polar orbit satellites according to the present invention, the satellite axis is set as the velocity vector direction on the earth to facilitate the processing of the satellite-mounted sensor data, and at the same time, the stereo pair sensor is used for the purpose of map creation and the like. To provide a means for reducing the deviation of the image.

[0009]

【Example】

Example 1. Embodiments of the present invention will be described below with reference to the drawings. In FIG. 1, 1 is a satellite structure, 2 is an earth sensor,
3 is a sun sensor, 4 is an attitude gyro, 5 is a timer device, 6 is a data processing device, and 7 is a reaction wheel.
Earth represents the earth.

FIG. 2 shows an example of the structure of the earth sensor 2 of FIG. 1, where Le is a condenser lens and DeI is an infrared photoelectric converter array. Further, FIG. 3 shows a configuration example of the sun sensor 3 of FIG. 1, S1 is an input light slit, and DeV is a photoelectric converter array block.

FIG. 4 shows an example of the configuration of the reaction wheel 7 of FIG. 1. Wh is an inertia flywheel and Mo is an acceleration / deceleration motor.

FIG. 5 is a diagram for explaining the function. In the figure, Earth is the earth, Orb is the trajectory of the satellite orbit, Sun is the sun, and Field is the field of view of the sun sensor.

In the apparatus of the present invention configured as described above, the field of view of the sun sensor 3 is oriented in the direction fixed to the satellite structure 1, and the boundary region where the satellite structure 1 appears in the sunshine range from the shadow of the earth. In Br, the direction of the sun can be captured in one plane within the fan-shaped region. The earth sensor 2 also captures thermal infrared rays from the earth and determines the direction of the center of the earth from the measurement of a certain width of infrared radiation. This 2
Since the attitude of the satellite at Br can be read from the two pieces of information, the value of the output signal of the attitude gyro 4 at this position is reset, and the attitudes of the three axes of the satellite are determined in the inertial space and stored in the data processing device 6. Further, the time information at the Br passing point is fetched from the timer 5 and stored. Since the orbiting period of the satellite is a constant value, the timer device 5
The difference between the time signal from and the Br passing time is calculated by the data processing device 6
If the calculation is performed, the latitude of the satellite passage point is calculated, and the earth rotation speed at this latitude can be calculated by the calculation formula stored in advance in the data processing device 6. Using the attitude information obtained from the attitude gyro 4, the above-mentioned earth rotation speed information, and the satellite speed information stored in advance in the data processing device 6, the direction of travel of the satellite fixed to the satellite and the coordinates fixed to the earth. It is possible to calculate the deviation in the velocity direction of the satellite in the system. The attitude of the satellite is controlled by changing the rotation speed of the acceleration / deceleration motor Mo connected to each inertia wheel Wh of the reaction wheel 7 so that this deviation information becomes zero. By the above operation, the attitude of the satellite coincides with the direction in which the satellite travels in the coordinate system whose traveling axis is fixed to the earth.

As described above, according to the method of the present invention, the traveling direction of the satellite and the axial direction of the satellite coincide with each other. Therefore, for example, when a push-bloom type sensor is mounted, the shape of the screen becomes a rectangle, and the analysis processing is performed. When creating a map, there is an advantage that processing such as composition area superposition is easy. In addition, when multiple observation sensors are installed on the satellite at the same time, the image of the point directly below and the image of the diagonally forward or backward direction are acquired, and when these are combined to obtain stereoscopic information, the coverage areas of the multiple sensors should be almost completely overlapped. It has an extremely highly practical advantage that data can be obtained and the data utilization efficiency can be improved.

Example 2. FIG. 6 shows a second embodiment of the present invention. In the figure, 8 is a movable sun sensor. Further, FIG. 7 shows a configuration example of the movable sun sensor 8, where Mi is a movable reflecting mirror for measuring the solar altitude, En is an angle reader, Dr is a movable mirror drive motor, Cnt is a drive mirror controller, and Mf. Is a fixed mirror.

In the above configuration, the drive motor Dr is controlled by the controller Cnt while the satellite is passing through the sunshine area where sunlight is irradiated.
The satellite altitude can be measured by moving the movable mirror so that the sunlight is guided to the sun detector 3 through the fixed mirror Mf and reading the rotation angle of the movable mirror by the encoder En by controlling the signal of The flying latitude can be directly measured, and this data is used instead of the output of the latitude calculation which uses the time signal calculated from the timer device of the first embodiment. It is possible to control the attitude of the satellite considering the influence.

Embodiment 3. FIG. 8 shows a third embodiment of the present invention. In the figure, 9 is a star sensor. FIG. 9 is a diagram showing a configuration example of a star sensor, Le is a condensing optical system, and Det is a two-dimensional detector array.

In the above configuration, by measuring a fixed star preset in the two-dimensional detector array Det of the star sensor 9 of the satellite and capturing the position change of the image on the two-dimensional plane, the flight latitude of the satellite is measured. By directly using this data by changing the data into the output of the latitude calculation using the time signal calculated from the timer device of the first embodiment, the satellite of the same kind as in the first embodiment, in which the influence of the earth rotation is taken into consideration. Attitude control becomes possible.

Example 4. FIG. 10 shows Embodiment 4 of the present invention. In the figure, 10 and 11 are linear photoelectric converter arrays 12 and 13, condensing optical systems, and 14 is a correlation calculator. The center of the visual field of the condensing optical system 12 faces the front direction in the plane including the traveling direction axis of the satellite from the center of the visual field of the condensing optical system 13. FIG. 11 is a diagram for explaining the function. In the figure, img1 is a linear photoelectric converter array 1
0 and an image for projecting the ground obtained by the condensing optical system 12, img2 is an image for projecting the ground obtained by the linear photoelectric converter array 11 and the condensing optical system 13, {p
1, p1 '} ... {pi, pi'} are representative points of the corresponding ground image in both images.

In the above configuration, as the satellite progresses in orbit, the condensing optical system 12 and the optical system of the linear photoelectric converter 10 in FIG. 10 first create a ground image img1 and collect it with a slight time lag. The optical system including the optical optical system 13 and the linear photoelectric converter 11 creates an image img2 of almost the same area on the ground. The correlation calculator 14 determines the position {pl ', p2' ... pi of the corresponding ground image of img2 corresponding to {p1, p2 ..., Pi} in img1.
′} Is obtained by the area correlation calculation of the minute area. Since the amount of deviation between the corresponding positions of the two from the center position of the screen is the deviation of the satellite's traveling axis from the ground, the attitude control of the satellite is performed so as to set it to zero. As the attitude control method, the same method as in the first embodiment of the present invention can be used. However, the attitude control method is not limited to this, and the electric current flowing through the coil wound in the plane including the yaw axis of the satellite and the rotational force due to the geomagnetism can be used. It can be operated in exactly the same way when used.

Example 5. FIG. 12 shows a sixth embodiment of the present invention. In the figure, 10 and 11 are linear photoelectric converter arrays 12, a condensing optical system, and 14 are correlation calculators. Further, FIG. 11 is a diagram for explaining the function, as in the fifth embodiment.

In the above structure, as the satellite advances in orbit, the condensing optical system 12 of FIG. 12 connects a two-dimensional image on the focal plane where the linear photoelectric converters 10 and 11 are installed, and The image of the specific point moves on the focal plane as the satellite progresses. Therefore, the optical system based on the linear photoelectric converter 10 creates an image img1 on the ground, and the focusing optical system 12 and the optical system based on the linear photoelectric converter 11 create an image img2 on the substantially same region on the ground with a slight time lag. . In the correlation calculator 14img1, {pl, p2 ...
., Pi}, the corresponding ground image position {p1 ', p2' ..., pi '} of img2 is obtained by area correlation calculation of the minute area. Since the amount of deviation between the corresponding positions of the two from the center position of the screen is the deviation of the satellite's traveling axis from the ground, the attitude control of the satellite is performed so as to set it to zero. As the attitude control method, the same method as in the first embodiment of the present invention can be used. However, the attitude control method is not limited to this, and the electric current flowing through the coil wound in the plane including the yaw axis of the satellite and the rotational force due to the geomagnetism can be used. It can be operated in exactly the same way when used. According to this method, the field of view of the sensor with respect to the satellite can be set with higher accuracy than the setting using two sensors.
There is an advantage that the accuracy of satellite attitude control can be improved.

Example 6. FIG. 13 shows a sixth embodiment of the present invention. In the figure, 15 and 16 are area photoelectric converter arrays 12 and 13, and a condensing optical system, and 14 is a correlation calculator. The center of the visual field of the condensing optical system 12 faces the front direction in the plane including the traveling direction axis of the satellite from the center of the visual field of the condensing optical system 13. FIG. 14 is a diagram for explaining the function. In the figure, img1 is a linear photoelectric converter array 1
5 and an image for projecting the ground obtained by the condensing optical system 16, img2 is an image for projecting the ground obtained by the linear photoelectric converter array 11 and the condensing optical system 13, {p1,
p1 '} ... {pi, pi'} are representative points of the corresponding terrestrial video in both images.

In the above configuration, as the satellite advances in orbit, the optical system formed by the condensing optical system 12 and the area photoelectric converter 15 in FIG.
g1 is created instantaneously, and the optical system including the condensing optical system 13 and the linear photoelectric converter 16 creates an image img2 of almost the same area on the ground with a slight time lag. Similarly, with a slight time difference, the optical system including the condensing optical system 12 and the linear photoelectric converter 15 creates an image img3 of a two-dimensional area on the ground, and the optical system including the condensing optical system 13 and the linear photoelectric converter 16 produces an image. Image of almost the same area on the ground as img2
To create. The correlation calculator 14 uses {p in img1
1, p2 ..., Pi}, the corresponding ground image position {pl ', p2' ..., pi '} of img2 is obtained by area correlation calculation of the minute area. The amount of deviation between the corresponding positions of the two from the center position of the screen reflects the change in the attitude toward the ground due to the relative time difference in the time difference at which each image is acquired, so the attitude control of the satellite is performed so as to be 0. As the attitude control method, the same method as in the first embodiment of the present invention can be used. However, the attitude control method is not limited to this, and the electric current flowing through the coil wound in the plane including the yaw axis of the satellite and the rotational force due to the geomagnetism can be used. It can be operated in exactly the same way when used.

Example 7. FIG. 15 shows Embodiment 7 of the present invention. In the figure, 15 and 16 are area photoelectric converter arrays, 12 is a condensing optical system, and 14 is a correlation calculator. FIG. 14 is a diagram for explaining the function similarly to the sixth embodiment.

In the above structure, as the satellite advances in orbit, the condensing optical system 12 of FIG. 15 connects a two-dimensional image on the focal plane where the area photoelectric converters 15 and 16 are installed, and The image of the specific point moves on the focal plane as the satellite progresses. The optical system by the area photoelectric converter 15 instantly creates a two-dimensional image img1 on the ground, and the optical system by the area photoelectric converter 16 instantly creates a two-dimensional image img2 of the almost same area on the ground with a slight time lag. . The correlation calculator 14 uses {p1, p2 ...
.., pi} corresponding ground image position of img2 {pl ', p2' ..., pi '} is obtained by area correlation calculation of the minute area. A change in the amount of deviation between the corresponding positions of the two from the screen center position causes a deviation of the satellite axis with respect to the ground in the time difference when two images are acquired. Therefore, the attitude control of the satellite is performed so that this becomes zero. . As the attitude control method, the same method as in the first embodiment of the present invention can be used. However, the attitude control method is not limited to this, and the current flowing through the coil surrounded by the yaw axis of the satellite and the rotational force due to the geomagnetism are used. It can be operated in exactly the same way when used.

Example 8. FIG. 16 shows an eighth embodiment of the present invention. In the figure, 15 is an area photoelectric converter array, 11 is a linear detector array, 12 is a condensing optical system, and 14 is a correlation calculator. FIG. 14 is a diagram for explaining the function similarly to the seventh embodiment. In the figure, img1 is an image projected on the ground obtained by the area photoelectric converter array 15 and the condensing optical system 12, img2 is an image projected on the ground obtained by the linear photoelectric converter array 11 and the condensing optical system 12, p1, p1 '} ... {pi, pi
′} Is the representative point of the corresponding terrestrial video in both images.

In the above configuration, as the satellite advances in orbit, first, the optical system including the condensing optical system 12 and the area photoelectric converter 15 in FIG. 16 instantaneously creates a two-dimensional image img1 on the ground for a short time. Condensing optical system 13 with a shift
And the optical system of the linear photoelectric converter 11 sequentially creates the image img2 of the almost same area on the ground line by line. The correlation calculator 14 uses {pl, p2 ..., p in img1.
position {p of the corresponding ground image of img2 corresponding to i}
1 ′, p2 ′ ..., Pi ′} are obtained by the area correlation calculation of the minute region. The amount of deviation of the corresponding positions from the center position of the screen is the difference between the image acquisition time of the linear sensor 11 and the image acquisition time of the area sensor 15, which is the deviation of the satellite's traveling axis from the ground. Represents a change. Therefore, the attitude control of the satellite is performed so that this is always zero. As the attitude control method, the same method as in the first embodiment of the present invention can be used. However, the attitude control method is not limited to this, and the electric current flowing through the coil wound in the plane including the yaw axis of the satellite and the rotational force due to the geomagnetism can be used. It can be operated in exactly the same way when used.

Example 9. FIG. 17 shows a ninth embodiment of the present invention. In the figure, 11 is a linear detector array, 12 is a condensing optical system, and 17 is a pointing mirror.
FIG. 18 is a diagram for explaining the function of the ninth embodiment. In the figure, img1 is an image for projecting on the ground, which is obtained when the pointing mirror 17 faces the direction directly below,
img2 An image projected on the ground with the pointing mirror 18 pointing in a direction deviating from the point directly below, {pl,
p1 '} ... {pi, pi'} are representative points of the corresponding terrestrial video in both images.

In the above structure, as the satellite advances in orbit, the optical system formed by the condensing optical system 12 and the area photoelectric converter 11 is grounded while the pointing mirror 18 in FIG. Image img1 of a certain time is created for a certain period of time, and the optical system including the condensing optical system 12 and the area photoelectric converter 11 forms the image img2 of the ground for a certain period of time with the pointing mirror 18 facing backward from the point directly below with a slight time lag. create. At this time, the pointing angle of the pointing mirror 18 is set to be substantially equal to img1 by using a preset value. The correlation calculator 14 uses {p1, p2 ... p in img1.
position {p of the corresponding ground image of img2 corresponding to i}
1 ′, p2 ′ ..., Pi ′} are obtained by the area correlation calculation of the minute region. The amount of deviation of the corresponding positions of the two from the center position of the screen is the deviation of the satellite's traveling axis with respect to the ground in the time interval for acquiring both images, so the attitude control of the satellite is performed so as to be 0. As the attitude control method, the same method as in the first embodiment of the present invention can be used. However, the attitude control method is not limited to this, and the electric current flowing through the coil wound in the plane including the yaw axis of the satellite and the rotational force due to the geomagnetism can be used. It can be operated in exactly the same way when used. According to this method, since only one linear sensor 11 for attitude detection is required, there is an advantage that the structure of the attached drive circuit can be simplified.

Example 10. FIG. 19 shows the first embodiment of the present invention.
It shows 0. In the figure, 15 is an area photoelectric converter array, 12 is a condensing optical system, and 18 is a pointing mirror. FIG. 20 is a diagram for explaining the function of the tenth embodiment. In the figure, img1 is a pointing mirror 18.
Image obtained by projecting the ground more when is directed to the direct lower point direction, image projected on the ground when the img2 pointing mirror 18 is directed in a direction deviated from the direct lower point, {p1, p1 '} ... • {pi, pi '} is the representative point of the corresponding terrestrial video in both images.

In the above structure, as the satellite advances in orbit, the optical system formed by the condensing optical system 12 and the area photoelectric converter 11 is first grounded while the pointing mirror 18 in FIG. 2D image img
1 is instantly created, and the optical system by the condensing optical system 12 and the area photoelectric converter 11 instantly creates a two-dimensional image img2 on the ground with the pointing mirror 18 facing backward from the direct point with a slight time lag. To do. At this time, the pointing angle of the pointing mirror 18 is set to be substantially equal to img1 by using a preset value. The correlation calculator 14 uses {p1, p2 ...
.., pi} corresponding ground image position of img2 {p1 ', p2' ..., pi '} is obtained by area correlation calculation of the minute area. The amount of deviation of the corresponding positions of the two from the center position of the screen is the deviation of the satellite's traveling axis with respect to the ground in the time interval for acquiring both images, so the attitude control of the satellite is performed so as to be 0. As the attitude control method, the same method as in the first embodiment of the present invention can be used. However, the attitude control method is not limited to this, and the electric current flowing through the coil wound in the plane including the yaw axis of the satellite and the rotational force due to the geomagnetism can be used. It can be operated in exactly the same way when used. According to this method, 2
Since the three-dimensional image is acquired instantaneously, there is an advantage that it is possible to remove the influence of the parallax distortion caused by the height of the ground point on the attitude detection error.

Example 11. FIG. 21 shows the first embodiment of the present invention.
1 is shown. In the figure, 18 and 19 are coherent pulse radar devices. Reference numeral 20 is a Doppler comparison calculator. FIG. 22 is a diagram for explaining the function. In the figure, Bm1 is the radiation beam of the transmission / reception antenna of the coherent pulse radar device 18, Bm2 is the radiation beam of the transmission / reception antenna of the coherent pulse radar device 19, D1 ... Di are equal to the Doppler shift frequency of the radar reflected waves when viewed from the satellite, etc. The Doppler line is shown.

In the above structure, as the satellite advances in orbit, pulsed radio waves are radiated toward the earth's surface from the coherent pulse radar devices 18 and 19 mounted on the satellite, the reflected waves are received, and the phase is received. Is detected. This phase-detected signal causes a Doppler frequency deviation corresponding to the ground speed of the satellite. When the azimuth of the radiation beam of the antenna is set symmetrically with respect to the traveling axis of the satellite, and when the traveling direction of the satellite on the earth fixed coordinate axis and the traveling axis of the satellite match, the coherent pulse radar device 17 And the Doppler frequency of the signal obtained from the coherent pulse radar device 18 match. If there is a deviation between the two, the deviation between the satellite's traveling axis and the velocity vector direction is calculated from the difference in Doppler frequency, and satellite attitude control is performed based on this. As the attitude control method, the same method as in the first embodiment of the present invention can be used. However, the attitude control method is not limited to this, and the electric current flowing through the coil wound in the plane including the yaw axis of the satellite and the rotational force due to the geomagnetism can be used. It can be operated in exactly the same way when used.

Example 12 FIG. 23 is a first embodiment of the present invention.
2 is shown. In the figure, 18 and 19 are coherent pulse radar devices. Reference numeral 20 is a Doppler comparison calculator, 21 is a difference signal generator, and 22 is a yaw control device.

In the above configuration, as the satellite advances in orbit, pulsed radio waves are radiated toward the earth's surface from the coherent pulse radar devices 17 and 18 mounted on the satellite, the reflected waves are received, and the phase is received. Is detected. This phase-detected signal causes a Doppler frequency deviation corresponding to the ground speed of the satellite. When the azimuth of the radiation beam of the antenna is set symmetrically with respect to the traveling axis of the satellite, and when the traveling direction of the satellite on the earth fixed coordinate axis and the traveling axis of the satellite match, the coherent pulse radar device 17 And the Doppler frequency of the signal obtained from the coherent pulse radar device 18 match. When there is a deviation between the two, a yaw error signal is generated due to the difference in Doppler frequency, and this is input to the yaw control device, and rotation control around the yaw axis is performed until the yaw error signal becomes zero. As described above, according to the method of the present invention, since the attitude control of the satellite can be performed in real time, for example, highly accurate image acquisition is possible, and it greatly contributes to improving the accuracy of map creation using satellite images. I can.

[0037]

As described above, according to the artificial satellite attitude control method of the present invention, it is possible to construct a terrestrial image pickup image system with less image distortion. It is extremely effective when used for remote sensors mounted on satellites, such as increasing the effective utilization area.

[Brief description of drawings]

FIG. 1 is a configuration diagram of a satellite attitude control method according to an embodiment of a first embodiment of the present invention.

FIG. 2 is a configuration diagram of an earth sensor according to an embodiment of the first embodiment of the present invention.

FIG. 3 is a configuration diagram of a sun sensor according to an embodiment of the first embodiment of the present invention.

FIG. 4 is a configuration diagram of a reaction wheel according to an embodiment of the first embodiment of the present invention.

FIG. 5 is an explanatory diagram of a function according to an embodiment of the first embodiment of the present invention.

FIG. 6 is a configuration diagram of a satellite attitude control method according to an embodiment of a second embodiment of the present invention.

FIG. 7 is a configuration diagram of a sun sensor according to an embodiment of a second embodiment of the present invention.

FIG. 8 is a configuration diagram of a satellite attitude control method according to an embodiment of a third embodiment of the present invention.

FIG. 9 is a configuration diagram of a star sensor according to an embodiment of a third embodiment of the present invention.

FIG. 10 is a configuration diagram of a satellite attitude control method according to an embodiment of a fourth embodiment of the present invention.

FIG. 11 is an explanatory diagram of a function according to an embodiment of the fourth embodiment of the present invention.

FIG. 12 is a configuration diagram of a satellite attitude control method according to an embodiment of a fifth embodiment of the present invention.

FIG. 13 is a configuration diagram of a satellite attitude control method according to an embodiment of the sixth embodiment of the present invention.

FIG. 14 is an explanatory diagram of a function according to an embodiment of a sixth embodiment of the present invention.

FIG. 15 is a configuration diagram of a satellite attitude control method according to an embodiment of the seventh embodiment of the present invention.

FIG. 16 is a configuration diagram of a satellite attitude control method according to an embodiment of an eighth embodiment of the present invention.

FIG. 17 is a configuration diagram of a satellite attitude control method according to an embodiment of the ninth embodiment of the present invention.

FIG. 18 is an explanatory diagram of a function according to an embodiment of the ninth embodiment of the present invention.

FIG. 19 is a configuration diagram of a satellite attitude control method according to an embodiment of a tenth embodiment of the present invention.

FIG. 20 is an explanatory diagram of a function according to an embodiment of the tenth embodiment of the present invention.

FIG. 21 is a configuration diagram of a satellite attitude control method according to an embodiment of an eleventh embodiment of the present invention.

FIG. 22 is an explanatory diagram of a function according to an embodiment of the eleventh embodiment of the present invention.

FIG. 23 is a configuration diagram of a satellite attitude control method according to an embodiment of the twelfth embodiment of the present invention.

FIG. 24 is a configuration diagram of a satellite attitude control method according to a conventional method.

FIG. 25 is an explanatory diagram of functions according to a conventional method.

[Explanation of symbols]

 1 Satellite Structure 2 Earth Sensor 3 Sun Sensor 4 Attitude Gyro Device 5 Timer Device 6 Data Processing Device 7 Reaction Wheel 8 Movable Sun Sensor 9 Star Sensor 10 Linear Photoelectric Converter Array 11 Linear Photoelectric Converter Array 12 Concentrating Optical System 13 Optical optics 14 Correlation calculator 15 Area photoelectric converter array 16 Area photoelectric converter array 17 Pointing mirror 18 Coherent pulse radar device 19 Coherent pulse radar device 20 Doppler comparison calculator 21 Difference signal generator 22 Yaw controller

Claims (12)

[Claims] 1. In the attitude control method of an artificial satellite that orbits the earth with an orbit passing near the north and south poles at an altitude of less than 1000 km, the attitude control outputs the three-axis attitude detector and the time when moving from shade to sunshine. Is used as a reference signal, and the ground velocity vector of the satellite is calculated by the on-board computer using the elapsed time from that time as a variable, and the direction of the tangential component on the earth of the point directly below the orbit of the satellite with respect to the earth and the structure of the satellite An attitude control method for an artificial satellite, characterized in that the yaw axis rotation angle of the satellite is given so that the body axis directions coincide with each other, and the attitude is controlled by program control. 2. A satellite directly below the point calculated by a satellite-mounted computer using a sun detector mounted on a satellite and using, as a reference signal, an output of a three-axis attitude detector and a signal indicating the sun direction obtained from the sun detector. Based on the latitude of the satellite, the ground speed vector of the satellite is calculated, and the direction of the tangential component on the earth of the locus of the point directly below the orbit of the satellite with respect to the earth matches the direction of the satellite structure axis in real time. 2. The attitude control method for an artificial satellite according to claim 1, which is a method for controlling the direction of the traveling axis and the ground velocity vector. 3. A satellite equipped with a star position detection imager,
3. The artificial satellite attitude control method according to claim 2, wherein the attitude of the satellite is calculated and used by utilizing the output of the three-axis attitude detector and the signal from the star position detection image device. 4. An attitude control method for an artificial satellite, the attitude control method comprising:
Using two or more optical imaging devices having a three-dimensional array detector array, the ground attitude calculated by a satellite-equipped computer using the output of the earth peripheral detector and the ground image obtained by the optical imaging device as reference signals. The attitude control method for an artificial satellite according to claim 2, wherein the method is a method for performing real-time yaw control based on data. 5. A method for controlling the attitude of an artificial satellite, comprising:
Using this optical imaging device having a one-dimensional array detector array, the ground attitude calculated by a satellite-equipped computer using the output of the earth peripheral detector and the ground image obtained by the optical imaging device as reference signals. 5. The artificial satellite attitude control method according to claim 4, wherein the method is a method for performing real-time yaw control based on data. 6. The attitude control method for an artificial satellite, wherein the attitude control method uses two or more optical imaging devices mounted on the satellite, each of which has an output of a peripheral detector of the earth and a two-dimensional array detector array. Then, the real-time yaw control is performed based on the attitude data calculated by the satellite-mounted computer, using the output of the earth periphery detector and the ground image obtained by the optical imaging device as reference signals. 4. The attitude control method for an artificial satellite according to 4. 7. The attitude control method for a satellite, wherein the attitude control method uses an optical imaging device mounted on the satellite and having an output of a peripheral detector and two or more two-dimensional array detector arrays. Then, the attitude control is characterized by performing real-time yaw control based on the attitude data calculated by the satellite-mounted computer, using the output of the earth periphery detector and the ground image obtained by the optical imaging device as reference signals. The attitude control method for an artificial satellite according to claim 4. 8. A satellite attitude control method, wherein the attitude control method comprises an optical imaging device mounted on a satellite, comprising an output of a peripheral detector of the earth, a one-dimensional array detector array, and a two-dimensional array detector array. Using the and, the yaw control is performed in real time based on the attitude data calculated by the satellite-mounted computer, using the output of the earth periphery detector and the ground image obtained by the optical imaging device as reference signals. 5. The artificial satellite attitude control method according to claim 4. 9. An attitude control method for an artificial satellite, wherein the attitude control method has an output of a peripheral detector of the earth and a one-dimensional array detector array mounted on the satellite, and a movable mirror is provided in front of the imaging optical system. Using the optical imaging device that has the real-time yaw control based on the result calculated by the satellite-equipped computer, using the output of the earth periphery detector and the ground image obtained by the optical imaging device as reference signals. The attitude control method for an artificial satellite according to claim 4, which is characterized in that. 10. An attitude control method for an artificial satellite, wherein the attitude control method has an output of a peripheral detector of the earth and a two-dimensional array detector array mounted on the satellite, and a movable mirror is provided in front of the imaging optical system. Performing real-time yaw control based on the attitude data calculated by the satellite-equipped computer, using the optical image pickup device that is provided with the output of the earth periphery detector and the ground image obtained by the optical image pickup device as reference signals. 5. The artificial satellite attitude control method according to claim 4. 11. A method of attitude control of an artificial satellite that orbits the earth at an altitude of less than 1000 km and passes near the north and south poles, wherein the attitude control uses the output of a Doppler radar signal detector mounted on the satellite as a reference signal. An attitude control method for an artificial satellite, characterized in that attitude control around the yaw axis of the satellite is performed by program control so that the frequency falls within a certain range. 12. A method for attitude control of an artificial satellite that orbits the earth at an altitude of less than 1000 km and passes near the north and south poles, wherein the attitude control uses the result of signal reception from a satellite-mounted geodetic support satellite system as a reference signal. , A satellite attitude control method characterized in that yaw control is controlled in a closed loop in real time so that the relative values thereof fall within a fixed value based on a predetermined calculation formula.