JPS5950896A - Attitude acquisition system of triaxial attitude control satellite - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an attitude control system for an artificial satellite, and particularly relates to an attitude acquisition system for a satellite using three-axis attitude control (f+).

Conventionally, an artificial bone using a three-axis attitude control method: At a star, the attitude extraction method of the artificial satellite F, which uses an inertial reference device (a device that detects the angular velocity 1 about each axis of the satellite) in the first group, was used. There are several r(;1 utterances. The main ones of these are
The angular velocity of the comet output from the F-reference device is divided into pieces using 1'-event methods such as the Euler parameter method, Euler angle method, Euler axis/Euler angle method, etc., and the successive "guard" attitude is determined. This is a method of subtracting the attitude error by detecting it, and based on it, performs fi'l+ for one attitude of 1.11μ. Although such a method is good at accurately detecting posture, it requires a special method for the above-mentioned integration. -IA is required, and %p I, +1〆1 itself is the main 11
It has the disadvantage that it becomes 11. In addition, there is also the firepower that Hayashide's original η-like, mathematical nature is transformed into a control system that is self-sufficient.

The purpose of Kienori II is to use the basic mathematical means mentioned above to detect posture, and also to improve posture control! The stability of the entire system can be improved by configuring it with a control system.
Three-axis posture flilli (
The goal is to provide a method for the 'fli stars'.

The present invention distributes the posture capture sequence into minute angles around each axis, applies closed-loop control only to the capture of each minute angle, and specifies the posture change of that minute angle using a sequence system*n. %? It is said that

According to the present invention, the means for detecting the satellite angular velocity in the three-axis directions of an artificial satellite subjected to three-axis attitude control; the means connected to the detecting means of and for integrating the angular velocity; A three-axis system for arbitrarily capturing the attitude of the artificial satellite, including means for generating an attitude earthquake signal, and means for controlling fC and rotation angles around each axis so as to make the output of the integrating means zero; A force acquisition method for attitude control 1 satellite is obtained.

The present invention will be described in detail below with reference to the drawings.

FIG. 1 is a block diagram showing an embodiment of the present invention. The reaction wheel 1 generates a torque 7 in the X-axis direction, and the X-axis gyro device 4 has an input shaft in the X-axis direction. It is of the type that outputs angular incremental pulses. 11 is a reference clock oscillator for the sequence system nt+, and the Euler angle fJt calculation counter 10 counts the number of pulses output from this oscillator 11, and when it reaches a value (Nα) corresponding to the rotation angle to the target attitude, Open the capture stop switch 12. The X-axis frequency divider 8 divides the pulse from the oscillator 11 into Nx in order to rotate around the X-axis at a foot rate ω.

The X-axis angle integral counter 7 is connected to the X-axis gyro device 4 and
Add the pulse output from 1 frequency divider 8 to 3? Count the things that are lost. The X-axis compensator 9 controls the attitude of the satellite so that the center of the counter 7 is exactly zero.The Y-axis control system 14 and the Z-axis control system 15 are devices having the same configuration as the X-axis control system 13. be.

FIG. 2 is a diagram showing the arrangement of each device on the satellite seat.

1' and 4' correspond to the X-axis action wheel 1 and the X-axis gyro device 4, respectively. 2 is a rear axis wheel that generates reaction torque in the Y-axis direction, 3 is the one in the Z-axis direction, and 5 is Y41. A gyro device having an input axis in the direction, similarly 6 is that in the Z-axis direction.

Next, the operation of this device will be explained. In FIG. 1, when the acquisition stop switch 12 is closed, a pulse frequency-divided by the X-axis frequency divider 8 to a frequency division ratio Nx is applied to the X-axis angle integral counter 7. As a result, the action wheel 1 along the X axis is controlled by the X Il + complementer 9 so that the number of pulses accumulated in the counter 7 becomes zero. The reaction torque generated by the reaction wheel 1 [the star body rotates around the X axis, the rotation is detected by the
By being fed back to the X-axis frequency divider 8, the input from the X-axis frequency divider 8 is suppressed. In this way, the opening device f7.
4-Angle integral counter 7-Sleeve (A & 9-Reaction wheel 1) The target direction is sequentially changed by the frequency divider 8 for the closed loop control system composed of A & 9-Reaction wheel 1.Here, if the frequency divider 8 Change of target direction (
If the pulse from the frequency divider 8 which is added to the counter 7 is sufficiently slow compared to the response of the closed loop control system, the satellite will rotate around the X axis at a constant speed.

This speed ωX is calculated by assuming that the reference frequency of the reference clock oscillator 11 is f (H2), and the storage of incremental pulses of the angle F1 of Become. Similarly, the Y axis and 2nd axis are also ω9. It rotates at a constant speed of ω2. These are the frequency division ratios Ny and Nz at that time.

On the other hand, it has been proven by Euler's theorem that any rotation of the satellite attitude can be achieved by rotating the Euler angle for each Euler decoy. Therefore, if the direction cosine of the Euler axis between the initial satellite attitude and the satellite attitude after the immersion time is (tm '' *n), and its Euler angle is α, then 1αitωx−1−rr+ br y 1n ωp.

t ・・・・・・・・・(2) A differential equation like the following holds true. Here, ωX, ωy, ω
2 is constant, and the ratio is selected as shown in the following equation (3) so that the ratio of the angles corresponds to the direction cosine of the Euler axis between the initial target attitude and the attitude to be captured.
, 61y:01m, ωy, = ωr+ ・Old---(3) Equation (2) is easily understood, and t, m, n
remains unchanged during rotation. If equation (3) is expressed in the form of a frequency division ratio, it becomes equation (4).

Nx==pf/rot, Ny--pf/6+m, P4
z=pf/a+n... (4) Also, by changing the equation for α in equation (2), we get α=ωt...
...(5) (where t is the rotation fA';Jr)). Here, ω=4': "x-+a+"!
By substituting equation (6) into equation (5) in A-c-'z, it can be calculated as Euler's intervening α+-1. Here, ft
il,, n error angle ffW counter] 0 ((more color), taking into account that tl is Nα
There is a relationship of . Therefore, if Nα is chosen, the star will obviously rotate by the Euler angle σ around the specified Euler axis and then stop.

In this analysis, the arbitrary rotation of the direction J... of the technique 9 according to the present application is achieved by rotating the Euler angle α of its Euler + 111''!
y, Nz) and Nα, it is automatically executed. In addition, since the rotation of each axis is controlled by simply capturing minute angles that are changed sequentially, there is no problem of geometric irregularities seen in conventional systems. Furthermore, as can be seen in the examples, the actual device does not require any complicated calculations or special equipment. Therefore, it is effective for attitude control of a three-axis attitude control satellite that does not have a computer installed.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an embodiment of the present invention, and FIG. 2 is a diagram showing the -F1 degree position of 1± between the satellites for each wound device shown in FIG. In the figure, j: a reaction wheel that generates torque in the X-axis direction, 4: a gyro device with Xt bending force direction input φ) 1j, 11: a reference clock Oscillator, 10...Euler angle product counter, 8...X-axis frequency divider, 7...
Addition/subtraction counter, 9...X-axis compensator, 13.
...X-axis control system, 14...Y-axis control system,
15... Z-axis control system, 2... Y-axis action wheel, 3... Z-axis action wheel, 5... Y-axis gyro device, 6...
...Z'X gyro device.

Claims (1)

[Claims] A signal generating means for generating signals for changing the satellite orientation in the three axes directions of an artificial satellite whose attitude is controlled in three axes, and a rotation angle around each axis i1 so as to suppress the output of the 4e' component means.
and a control means for controlling a three-axis attitude 11il control satellite to arbitrarily capture the attitude of the artificial 〒1JIμ.