JP2000247298A - Attitude/orbit control method for artificial satellite - Google Patents

Abstract

PROBLEM TO BE SOLVED: To use a propulsion unit for south-north orbit control and a propulsion unit for east-west orbit control in common by concurrently injecting two pairs of propulsion units for south-north and east-west orbit control in south-north orbit control. SOLUTION: An injection time control device 20 controls the injection of a propulsion unit A and a propulsion unit B according to the orbit position. Injection signals (a) and (b) generated by the injection time control device 20 are fed to a propulsion unit drive device 21 to drive the propulsion unit A and the propulsion unit B. In east-west orbit control (acceleration maneuver), the injection signal is generated for the propulsion unit B at the maneuver position, and an acceleration maneuver is implemented. In south-north orbit control, the propulsion unit A and the propulsion unit B are concurrently injected at the orbit control position.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention
It relates to an orbit control method.

[0002]

2. Description of the Related Art FIG. 13 is a diagram showing an arrangement of a propulsion device when a conventional satellite attitude / orbit control device is used. In FIG. 13, reference numerals 1 and 2 denote north-south orbit control propulsion devices, and reference numerals 3 and 4 denote east-west orbit control propulsion devices.

The conventional satellite attitude / orbit control device is configured as described above. When performing north-south orbit control, a propulsion device for performing north-south orbit control is operated at a predetermined orbit position for a predetermined time, Orbit control is performed by injection. Similarly, when performing the east-west orbit control, the propulsion device that performs the east-west orbit control is injected at a predetermined orbit position for a predetermined time to perform the orbit control.

FIG. 14 is a diagram showing an arrangement of a propulsion device when a conventional satellite attitude / orbit control device is used. In FIG. 14, reference numerals 1 and 2 denote north-south orbit control propulsion devices, and reference numerals 3 and 4 denote east-west orbit control propulsion devices. 5
Is a propulsion device for attitude control used for unloading and attitude control of the wheel. Reference numeral 6 denotes a wheel used for performing attitude control.

The conventional satellite attitude / orbit control device is configured as described above. When performing north-south orbit control, a propulsion device for performing north-south orbit control is operated at a predetermined orbit position for a predetermined time, Orbit control is performed by injection. Similarly, when performing the east-west orbit control, the propulsion device that performs the east-west orbit control is injected at a predetermined orbit position for a predetermined time to perform the orbit control. Attitude control is performed with wheels. When the attitude control is performed with the wheel,
Since the angular momentum of the wheel is saturated by the accumulated disturbance component, the unloading of the wheel is performed by the propulsion device for attitude control.

[0006]

When the conventional attitude / orbit control device performs north-south orbit control and east-west orbit control, it is necessary to mount an independent propulsion device. For this reason, the scale of the propulsion device is increased, and there are disadvantages in weight, mountability, and cost.

In the conventional attitude / orbit control device, when performing north-south orbit control and east-west orbit control, it is necessary to use an independent propulsion device. In addition, it is necessary to mount a propulsion device for attitude control for generating angular momentum on each axis of the satellite independently of the above-mentioned propulsion device for orbit control also for wheel unloading. For this reason, the scale of the propulsion device is increased, and there are disadvantages in weight, mountability, and cost.

The present invention has been made to solve such a problem, and has as its object to significantly reduce the size of a propulsion device.

[0009]

According to a first aspect of the present invention, a method for controlling the attitude and orbit of an artificial satellite controls the injection time of a propulsion device capable of generating thrust in the north-south direction and the east-west direction in accordance with the orbit position, and controls the north-south orbit. Is performed by simultaneously injecting two pairs of propulsion devices for north-south and east-west orbit control, and east-west orbit control is performed by increasing or decreasing the speed at a predetermined orbit position. Speed-up maneuver and deceleration maneuver are implemented by selecting one of two pairs of propulsion devices for north-south / east-west orbit control. The effect of the north-south velocity component on the orbit caused by the speed-up maneuver and deceleration maneuver is performed by simultaneous injection of two pairs of propulsion devices for north-south and east-west orbit control when the orbital position is shifted by 180 degrees by the injection time controller To be removed.

The satellite attitude / orbit control method according to the second invention controls the injection time of a propulsion device capable of generating thrust in north-south and east-west directions according to the orbit position.
The set angle of the gimbal on which the propulsion device is mounted is controlled according to the orbital position. The north-south orbit control is performed by simultaneously injecting two pairs of propulsion devices for north-south and east-west orbit control, and the east-west orbit control is performed by increasing or decreasing the speed at a predetermined orbit position. Speed-up maneuver and deceleration maneuver are 2
It is implemented by selecting one of the propulsion devices for paired north-south / east-west orbit control. The effect of the north-south velocity component on the orbit caused by the speed-up maneuver and deceleration maneuver is performed by simultaneous injection of two pairs of propulsion devices for north-south and east-west orbit control when the orbital position is shifted by 180 degrees by the injection time controller To be removed. When unloading the angular momentum accumulated in the wheel at a predetermined orbital position, the gimbal angles of the two pairs of gimbals are set at a predetermined angle. After setting the angle, torque can be independently generated around the roll, pitch, and yaw axes of the satellite by simultaneously injecting two pairs of propulsion devices for north / south / east / west orbit control. Since the angular momentum corresponding to the injection time is generated, the time required for unloading is set. The effect on the orbit due to the simultaneous injection of the propulsion device for north-south and east-west orbit control performed to carry out unloading is two pairs of north-south and east-west orbit control when the orbital position is shifted by 180 degrees by the injection time control device. It is removed by co-injecting the propulsion device.

The satellite attitude / orbit control device according to the third invention uses a thruster, an ion engine or an arc jet as a propulsion device in the first invention and the second invention.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiment 1 FIG. 1 is a diagram showing an arrangement of a propulsion device according to an embodiment of the present invention. FIG. 3 is a block diagram showing one embodiment of the present invention.

In FIG. 1, reference numeral 7 denotes a propulsion device (propulsion device A) used for performing north-south orbit control and east-west orbit control. The propulsion device 7 is arranged so that its thrust axis passes through the center of gravity of the satellite. In addition, they are arranged to have thrust components in the north-south direction and the east-west direction. Similarly, reference numeral 8 denotes a propulsion device (propulsion device B) used for performing north-south orbit control and east-west orbit control. The propulsion device 8 is also arranged so that its thrust axis passes through the center of gravity of the satellite. In addition, they are arranged to have thrust components in the north-south direction and the east-west direction. In FIG. 3, reference numeral 7 denotes a propulsion device A for performing north-south orbit control and east-west orbit control. 8 is likewise
This is a propulsion device B for performing north-south orbit control and east-west orbit control. Reference numeral 21 denotes a propulsion device driving device for driving the propulsion device. 20 is a propulsion device A according to the orbital position
And an injection time control device for controlling the injection time of the propulsion device B.

Next, the operation will be described. In FIG. 3, the injection time control device controls the injection of the propulsion devices A and B according to the orbital position. The injection signals A and B generated by the injection time control device 20 are input to the propulsion device drive device 21 to drive the propulsion devices A and B. FIG. 5 shows the injection timing for the propulsion devices A and B in the east-west orbit control (increase and deceleration) and the north-south orbit control generated by the injection control device 20. In east-west orbit control (speed-up maneuver), an injection signal is generated in the propulsion device B at the maneuver position, and speed-up maneuver is performed. The thruster generates thrust in the east-west direction and also in the north-south direction. However,
The propulsion device A and the propulsion device B are shifted by 180 degrees from the maneuver position so that the propulsion device A and the propulsion device B are half the time of the speed-up maneuver,
By injecting, the influence on the orbit inclination angle is canceled. East-west orbit control (deceleration maneuver) is also implemented. The north-south orbit control is performed by simultaneously injecting the propulsion devices A and B at the orbit control position.

Embodiment 2 FIG. 2 is a diagram showing the arrangement of the propulsion device and the wheels in one embodiment of the present invention. FIG. 4 is a block diagram showing one embodiment of the present invention.

First, the arrangement of the propulsion device and the wheels will be described. In FIG. 2, reference numeral 7 denotes a propulsion device (propulsion device A) used for performing north-south orbit control and east-west orbit control. The propulsion device 7 is mounted on a biaxial gimbal 9 (biaxial gimbal A), and is arranged so that its thrust axis passes through the center of gravity of the satellite at a predetermined gimbal angle. Also,
It is arranged to have thrust components in north-south direction and east-west direction. Similarly, reference numeral 8 denotes a propulsion device (propulsion device B) used for performing north-south orbit control and east-west orbit control. The propulsion device 8 is also a biaxial gimbal 10 (biaxial gimbal B).
At a predetermined gimbal angle, the thrust axis of which is arranged to pass through the center of gravity of the satellite. In addition, they are arranged to have thrust components in the north-south direction and the east-west direction. Reference numeral 6 denotes a wheel used for attitude control.

Next, a configuration diagram will be described. In FIG. 4, reference numeral 7 denotes a propulsion device A for performing north-south orbit control and east-west orbit control. Reference numeral 8 is a propulsion device B for implementing north-south orbit control and east-west orbit control. 21
Is a propulsion device driving device for driving the propulsion device.
Reference numeral 20 denotes an injection time control device that controls the injection time of the propulsion devices A and B according to the orbital position. 9 is a biaxial gimbal A on which the propulsion device A is mounted. Reference numeral 10 denotes a two-axis gimbal B on which a propulsion device B is mounted. A gimbal driving device 22 drives the two-axis gimbal A and the two-axis gimbal B. Reference numeral 23 denotes a gimbal angle control device that controls the set angles of the two-axis gimbal A and the two-axis gimbal B according to the orbital position.

The operation will be described below. First, the trajectory control will be described. In FIG. 4, the injection time control device controls the injection of the propulsion devices A and B according to the orbital position. The injection signals A and B generated by the injection time control device 20 are input to the propulsion device drive device 21 to drive the propulsion devices A and B. FIG. 5 shows the injection timing for the propulsion devices A and B in the east-west orbit control (increase and deceleration) and the north-south orbit control generated by the injection control device 20. In east-west orbit control (speed-up maneuver), an injection signal is generated in the propulsion device B at the maneuver position, and speed-up maneuver is performed. The propulsion device generates thrust in the east-west direction and also generates thrust in the north-south direction. However, by injecting the propulsion devices A and B at the orbital position shifted by 180 degrees from the maneuver position for half the time of the speed-up maneuver, the influence on the orbit inclination angle is canceled. East-west orbit control (deceleration maneuver) is also implemented. The north-south orbit control is performed by simultaneously injecting the propulsion devices A and B at the orbit control position.

Next, the attitude control will be described. The posture control is performed by the wheel 6. However, since the wheel angular momentum has an upper limit, if it exceeds this, it is necessary to perform unloading by generating an external torque. Here, the angle of the biaxial gimbal on which the propulsion device is mounted is appropriately selected, and an external force torque is generated by injecting the propulsion device for a predetermined time, thereby performing unloading of the wheel.

FIG. 6 shows that by setting the two-axis gimbal angle and injecting the propulsion device, torque can be generated around each axis of the satellite. The angular momentum is obtained by multiplying the generated torque by the injection time. If the propulsion device is injected to perform unloading, a thrust component will be generated in the north-south direction of the satellite, and this will affect the inclination angle of the orbit. The gimbal angle control device shown in FIG.
The impulse amount equivalent to the north-south impulse amount generated at the orbital position shifted by degrees is given, and the influence on the orbit inclination angle is canceled.

FIGS. 7 to 12 show the setting of the gimbal angle and the injection timing of the propulsion device when the unloading of each axis is performed. When unloading is performed, angular momentum about each axis is obtained, but at the same time, velocity components in the north-south direction and east-west direction are generated. According to the above timing diagram, these unnecessary speed components can be canceled.

[0022]

According to the present invention, the propulsion device for north-south orbit control and the propulsion device for east-west orbit control can be shared, and the scale of the propulsion device can be greatly reduced.

According to the present invention, the propulsion device for north-south orbit control and the propulsion device for east-west orbit control can be shared. Further, since the unloading of the wheel can be performed by the above-described propulsion device, the scale of the propulsion device can be significantly reduced.

[Brief description of the drawings]

FIG. 1 is a diagram showing an arrangement of propulsion devices for north-south orbit control and east-west orbit control according to Embodiment 1 of the present invention.

FIG. 2 is a diagram showing an arrangement of propulsion devices, wheels, and gimbals for north-south orbit control, east-west orbit control, and wheel unloading, showing Embodiment 2 of the present invention.

FIG. 3 is a configuration diagram showing the first embodiment of the present invention.

FIG. 4 is a configuration diagram showing a second embodiment of the present invention.

FIG. 5 shows the injection timing of the injection control device.

FIG. 6 is a diagram showing that torque is generated around each satellite axis by setting a gimbal angle.

FIG. 7 is a timing chart showing that a positive angular momentum is generated around a roll axis by setting a gimbal angle.

FIG. 8 is a timing chart showing that a negative angular momentum is generated around a roll axis by setting a gimbal angle.

FIG. 9 is a timing chart showing that a positive angular momentum is generated around a pitch axis by setting a gimbal angle.

FIG. 10 is a timing chart showing that a negative angular momentum is generated around a pitch axis by setting a gimbal angle.

FIG. 11 is a timing chart showing that a positive angular momentum is generated around the yaw axis by setting a gimbal angle.

FIG. 12 is a timing chart showing that a negative angular momentum is generated around the yaw axis by setting the gimbal angle.

FIG. 13 shows an arrangement of a propulsion device when a conventional attitude / orbit control system of an artificial satellite is used.

FIG. 14 shows an arrangement of propulsion devices and wheels when a conventional satellite attitude / orbit control system is used.

[Explanation of symbols]

1 propulsion device for north-south orbit control, 2 propulsion device for north-south orbit control, 3 propulsion device for east-west orbit control, 4 propulsion device for east-west orbit control, 5 propulsion device for attitude control, 6 wheels,
7 Propulsion device A, 8 Propulsion device B, 9 2-axis gimbal A, 10 2-axis gimbal B, 20 Injection control device, 21
Propulsion device drive device, 22 Gimbal drive device, 23
Gimbal angle control device, A injection time control signal A, B injection signal control signal B, gimbal angle control signal A, gimbal angle control signal B, E propulsion device A drive signal, F propulsion device B drive signal, G gimbal A Drive signal, gimbal B drive signal.

Claims (3)

[Claims] 1. A propulsion device disposed at two places on a satellite such that a thrust axis passes through the center of gravity of the satellite and has thrust components in the north-south direction and the east-west direction of the satellite, and a propulsion device drive device for turning on and off the propulsion device. An injection time control device that controls the injection time of the propulsion device according to the orbital position is provided.When performing north-south orbit control, the propulsion device performs the orbit control by simultaneously injecting the propulsion device at the north-south orbit control execution position. In east-west orbit control, orbit control is carried out by injecting one of the above propulsion units at half of the total orbit control time at two locations where the orbit position is almost 180 degrees apart, and the north-south orbit control and the east-west orbit control are the same. A method for controlling the attitude and orbit of an artificial satellite, which is performed by a propulsion device. 2. A propulsion device disposed at two places on the satellite such that the thrust axis passes through the center of gravity of the satellite and has thrust components in the north-south direction and the east-west direction of the satellite, and a propulsion device drive device for turning on and off the propulsion device. An injection time control device that controls the injection time of the propulsion device according to the orbital position, and a gimbal angle control device that sets the gimbal angle according to the orbital position. By controlling, the impulse and angular momentum other than the required impulse and angular momentum are removed in one round of the orbit, and north-south orbit control, east-west orbit control, and wheel unloading are performed by the same propulsion device. Attitude of artificial satellite
Orbit control method. 3. The artificial satellite attitude / orbit control device according to claim 1, wherein said propulsion device is a thruster, an ion engine or an arc jet.