JPH01297399A - Attitude controller for artificial satellite - Google Patents

Abstract

PURPOSE:To secure the high precision of the attitude precision by obtaining the attitude control signal by converting the attitude error of a satellite dynamics to the values on the coordinate system of a developed structure body such as solar battery paddle and converting said signal to the values on the coordinate system of the satellite dynamics and controlling the attitude of the satellite dynamics. CONSTITUTION:In the application to a satellite dynamics 12 in which a developed structure body 11 is arranged in rotatable ways around the pitch (Y) axis of the satellite body 10 of an artificial satellite, a roll detecting sensor 13 and a yaw detecting sensor 14 for detecting the roll attitude error around the roll (X) axis of the satellite dynamics 12 and the yaw attitude error around a yaw (Z) axis are installed. The output signals of the sensors 13 and 14 are inputted into the first coordinate conversion part 16, and converted to the values on the coordinate system of the developed structure body 1, and outputted into the Xp and Zp control calculation parts 17 and 18. The roll and yaw control signals in the coordinate system are obtained and sent into the second coordinate conversion part 19, and converted to the values on the coordinate system of the satellite dynamics 12, and the drive control for an actuator 15 for attitude drive is carried out.

Description

DETAILED DESCRIPTION OF THE INVENTION [Objective of the Invention (Industrial Application Field) This invention relates to an attitude control device for an artificial satellite equipped with a deployable structure such as a solar battery.

(Prior Art) Recently, in addition to increasing the size of artificial satellites, attempts have been made to increase the precision of attitude control. By the way, in such artificial satellites, as the size of the satellite increases, the flexibility of the deployable structure increases, so the natural frequency of the deployable structure must be within the control bandwidth of the attitude control system. It has the problem of being included. Therefore, as a control method, the phase of the open-loop control characteristic of the low-order vibration mode is -18°.

Create a control system with sufficient margin from In-stabilization is employed.

FIG. 3 shows an attitude control device for an artificial satellite using such a control method. For example, as shown in FIG. A case where the method is applied to satellite dynamics 12 freely arranged will be explained as a representative example. That is, in the satellite dynamics 12, the roll attitude error around the roll (X) axis and the yaw attitude #+ error around the yaw (Z) axis are detected by the roll detection sensor 13 and the yaw detection sensor 14. The roll and yaw detection sensors 13 and 14 output their roll and yaw attitude error signals to the roll and yaw control number calculation unit 1.2. Then, the roll and yaw control signal calculation units 1 and 2 determine the roll and yaw control signals, respectively, and drive and control the attitude drive actuator 15. In response to this, the actuator 15 changes the attitude of the satellite dynamics 12.

However, in the above-mentioned attitude control device for an artificial satellite, due to its configuration, as shown in FIG.
X, axis and 2 of the deployed structure 1 relative to ltl. When the axes no longer correspond, the in-plane (I P ) m-motion mode and the out-of-plane (OF) vibration mode coexist around the X and Z axes, as shown in Figure 6, resulting in the vibration mode of the deployed structure. is in a dense state, which poses a problem in that it is difficult to stabilize the phase of the low-order vibration mode/stabilize the gain of the high-order peristaltic mode. For this reason, the design process is extremely complicated, and
This poses a problem in that attitude control accuracy decreases and it becomes difficult to stabilize attitude control. This makes it difficult to meet the demands for high attitude control, especially as the deployment structure 11 becomes more flexible as the satellite becomes larger.

This situation is such that the deployable structure 1
A similar problem occurs even when one rotational axis is arranged at an angle.

(Problems to be Solved by the Invention) As described above, in the conventional attitude control device for an artificial satellite, it is difficult to prevent the drive modes of the deployable structure from becoming denser.

This invention was made in consideration of the above circumstances, and by separating the vibration modes of a deployable structure, it is possible to simplify the design process and achieve high precision and stability of attitude control. The purpose of this project is to provide an attitude control system for artificial satellites.

[Structure of the Invention (Means for Solving Problems)] An artificial satellite attitude control device It according to the present invention includes a detection means for detecting an attitude error in satellite dynamics whose attitude is controlled via an actuator, and this detection means. and a control means for converting the attitude error signal into the coordinate system of the deployed structure to obtain an attitude control signal, and converting the attitude control signal into the coordinate system of the satellite dynamics to drive and control the actuator. It is something.

(Function) According to the above configuration, the attitude control signal converts the attitude error (M) detected from the satellite dynamics into the coordinate system of the deployed structure, calculates the attitude control value from the converted attitude error signal, It is generated by converting this to the satellite dynamics coordinate system.As a result, the vibration mode of the deployed structure can be separated into, for example, an out-of-plane mode and an in-plane mode, and a The first mode is phase stable,
Gain stability and stabilization can be achieved in the second-order mode and above. Therefore, it is possible to simplify the design process and improve the precision and stability of attitude control.

(Example) Hereinafter, an example of the present invention will be described in detail with reference to the drawings.

FIG. 1 shows an attitude control system 1tfc for an artificial satellite according to an embodiment of the present invention, in which a deployable structure 1 is placed at the pitch (Y) axis axis 9 of the satellite main body 10 as shown in FIG. A case will be explained as a representative case where it is applicable to satellite dynamics No. 2 which is rotatably arranged. However, in Figure 1, the conventional third
The same parts as those in the figures are given the same reference numerals, and the description thereof will be omitted.

That is, the satellite dynamics 12 has its role (X)
The roll attitude i difference of the axis rotation and the yaw attitude error around the yaw (Z) axis are detected by the roll detection sensor 13 and the yaw detection sensor 14.
Detected by This roll and yaw detection sensor 13
, 14 outputs the roll and yaw attitude error signals to the first coordinate conversion section 16. This first coordinate conversion unit 16 performs coordinate conversion of the input roll and yaw attitude error signals, and converts the input roll and yaw attitude error signals into the coordinate system (X axis,
Y axis, Z axis) and X, and 2. control p
p p Output to the control calculation units 17 and 18. This X and 2° control (iI calculation section 1718 is the coordinate thread (x, axis, Yp axis.

2. Determine the roll and yaw control signals for the second axis
output to the coordinate conversion section 19. This second coordinate exchange section 1
9 is the input coordinate system (X, axis, Y, axis.

The roll and yaw control signals in the satellite dynamics 12 (DPJ! axis) are transformed again into the satellite dynamics 12 (DPJ!
! It is converted into a standard system (X@, Y axis, 2 axes) and output to the actuator 15 for attitude drive. Thereby, the actuator 15 controls the attitude of the satellite dynamics 12.

In this manner, the satellite attitude control device transmits the attitude error signal detected from the satellite dynamics 12 to the deployed structure 11.
The attitude control value is obtained from the converted attitude error signal, and the actuator 15 is driven and controlled by the attitude control signal generated by converting this into the coordinate system of the satellite dynamics 12. It was configured as follows. In this case, when the vibration mode of the deployable structure 11 is one, for example, as shown in FIG. 18
A control method that stabilizes the gain characteristic by taking a sufficient phase margin from 0') and gain stability (a control method that stabilizes the gain characteristic by taking a sufficient gain margin from OdB) is facilitated. Therefore, compared to the conventional structure in which the vibration mode of the deployed structure 1 is in a tight state where the in-plane and out-of-plane modes are straight (see Fig. 6), the design is as simple as possible. Manufacturability can be simplified, and posture control can be highly accurate and stabilized.

In addition, in the above embodiment, the rotation axis (Y,
Although a case has been described in which the configuration is such that the axis (axis) corresponds to the yp axis of the satellite dynamics 12, the present invention is not limited to this arrangement and is applicable. Therefore, it goes without saying that the present invention is not limited to the embodiments described above, and that various modifications can be made without departing from the spirit of the invention.

[Effects of the Invention] As described in detail above, according to the present invention, the vibration modes of a deployable structure are separated, thereby simplifying the design table, and improving the precision and stability of attitude control. It is possible to provide an attitude control device for an artificial satellite that can realize the

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an attitude control device for an artificial satellite according to an embodiment of the present invention, FIG. 2 is a diagram showing vibration mode 0 of the deployable structure in the attitude control signal of FIG. 1, and FIG. Block diagram showing a conventional attitude control device for an artificial satellite, No. 4
5 and 5 are diagrams showing an artificial satellite to which the present invention is applied, and FIG. 6 is a diagram showing the vibration mode of the deployed structure in the attitude control signal of the conventional artificial satellite attitude control device shown in FIG. 3. . 10... Satellite main body, 1... Deployment structure, 12...
・Satellite dynamics, 13...Roll detection sensor, 1
4... Yaw detection sensor, 15... Actuator,
16...2gl coordinate transformation unit, 11X, control calculation unit,
18...2. Control calculation unit, 19... second coordinate transformation unit. Applicant's agent Patent attorney Takehiko Suzue Figure 5 Figure 6

Claims (1)

[Claims] In an attitude control device for an artificial satellite equipped with a deployable structure, there is provided a detection means for detecting an attitude error in satellite dynamics whose attitude is controlled via an actuator, and an attitude error signal of the detection means that is used to determine the coordinates of the deployable structure. 1. An attitude control device for an artificial satellite, comprising: control means for converting the attitude control signal into a coordinate system of the satellite dynamics to obtain an attitude control signal, and converting the attitude control signal into a coordinate system of the satellite dynamics to drive and control the actuator.