JPH072480B2 - Three-axis attitude control device for satellite - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention is used for three-axis attitude control of an artificial satellite. In particular, it relates to the direction control of the rotation axis of the momentum wheel provided in a bias momentum type artificial satellite.

〔Overview〕

According to the present invention, one momentum wheel for controlling the rotation torque around the z-axis and two axes (x-axis, y-axis) substantially orthogonal to the rotation axis of the momentum wheel and orthogonal to each other.
In a three-axis attitude control device for an artificial satellite that performs attitude control by generating control torques in each of the (axis) directions, a rotor mounted on two gimbals each having a support axis parallel to the x-axis and the y-axis is provided. By combining the control means for forcibly rotating the gimbal around the support shaft, a large mechanism can instantly generate a large control torque with a simple mechanism.

[Conventional technology]

BACKGROUND ART Conventionally, a momentum wheel is provided in an artificial satellite whose three-axis attitude is controlled by a bias momentum method.
The direction control of the rotor rotary shaft of this momentum wheel uses a magnetic torquer, a gas jet, or a reaction wheel in order to apply a predetermined torque in two directions respectively perpendicular to the rotor rotary shaft.

[Problems to be solved by the invention]

However, the method using the magnetic torquer utilizes the torque generated by the interaction between the magnetic moment generated by the magnetic torquer and the earth's magnetic field.

Therefore, the control torque is generated only on the plane perpendicular to the earth's magnetic field, and the torque is extremely small.

On the other hand, the gas jet type has a limitation that the life of the fuel is limited, the sloshing of the fuel in the tank adversely affects the attitude control motion, and the jet injection pollutes the surrounding space. .

The reaction wheel method has the drawbacks that the apparatus becomes large and the weight becomes large.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a three-axis attitude control device for an artificial satellite that solves this drawback, is small and lightweight, and can instantly generate a large torque at any time.

[Means for solving problems]

The present invention includes one moment wheel and two sets of torque generating means that generate a predetermined amount of torque independently in the directions of two axes that are substantially orthogonal to the rotation axis of the moment wheel and are orthogonal to each other. In the three-axis attitude control device for an artificial satellite, the two sets of torque generating means include two sets of gimbals each mounted with one rotor, and each support shaft of the gimbals corresponds to the two shafts. It is characterized in that it is provided with means for arranging the gimbals in parallel and rotating the gimbals around the respective support shafts.

[Action]

A high-mass momentum wheel rotates about the z-axis at high speed. A small mass rotor is rotating in a gimbal provided parallel to the x-axis and the y-axis. By forcibly rotating the support shaft of the gimbal in this state, a control torque can be generated around the x axis or the y axis.

This control torque can be generated by the pivoting means at any time in a considerable amount.

In order to restore the once-rotated gimbal support shaft to its original position, a magnetic torquer can be used, for example, to slowly perform it when there is time to spare.

〔Example〕

Next, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is an explanatory diagram showing the configuration of an embodiment of the present invention. In this figure, the moment wheel 4 has a rotor rotation axis in the satellite coordinate axis z direction, controls the rotation of the satellite around the coordinate axis z, and stabilizes the satellite in the coordinate axis z direction by the gyro stiffness due to this bias angular momentum. It is a thing.

The feature of the present invention here is that the rotating shafts of the gimbals 5A and 6A equipped with two control moment gyros 5 and 6 are mounted on the bearings 5L, 5R and 6 respectively.
Supported by L and 6R, the axes 2 and 1 are coordinate axes x
And y-direction, respectively. The control moment gyro 5 can rotate about the coordinate axis y direction as an arrow a. Further, the control moment gyro 6 generates control torque by rotating about the coordinate axis x direction as shown by an arrow b to perform control around the axes x and y.

The motors 13A and 13B are means for forcibly rotating the support shafts of the gimbals 5A and 6A.

FIG. 2 is a block diagram of the control system of this embodiment. In this figure, the control drive unit 12A drives the drive motor 13A in either forward or reverse directions so that the command A of the control circuit 11 causes the gimbal to rotate around the support shaft 2 of the gimbal 5A shown in FIG. Rotate slightly. At this time, as shown in FIG. 1, the rotation axis of the rotor 5 is inclined with respect to the coordinate axis z, so that the gimbal 5A generates torque around the x axis in either positive or negative directions. As shown in FIG. 2, the result of the artificial satellite dynamics 14 is sent to the control circuit 11 via the attitude determining circuit 16 by the attitude sensor 15 to determine whether or not this torque is suitable for the attitude control of the artificial satellite. To be fed back.

When controlling the gimbal 6A in FIG. 1, the command B is similarly sent from the control circuit 11 in FIG.

A known method is used as a method of applying a rotational torque about the z-axis by the rotational speed of the momentum wheel 4 and a mechanism for releasing the accumulation of angular momentum generated thereby.

Further, when the support shafts of the gimbals 5A and 6A are forcibly rotated to perform posture control, and when these are accumulated to accumulate external torque, the deviation of the support shafts becomes large. To recover the bias of the support shaft, use a magnetic torquer (not shown),
Do this slowly over a long period of time.

As a result, the posture control can be performed by suddenly generating a large torque without providing the jet injection.

〔The invention's effect〕

As described above, according to the present invention, it is possible to obtain the attitude control of an artificial satellite that can instantly generate a control torque in any direction without increasing the size of the device.

According to the present invention, the control by jet injection can be extremely reduced or eliminated.

[Brief description of drawings]

FIG. 1 is an explanatory diagram showing the configuration of an embodiment of the present invention. FIG. 2 is a block diagram of the control system of the above embodiment. 1, 2 ... Direction of gimbal rotation axis, 4 ... Momentum wheel, 5, 6 ... Rotor, 5A, 6A ... Gimbal,
5L, 5R, 6L, 6R …… Bearing, 11 …… Control circuit, 12A, 12B…
... Control drive unit, 13A, 13B ... Drive motor, 14 ... Artificial satellite dynamics, 15 ... Attitude sensor, 16 ... Attitude determination circuit, A, B, C, D ... Command, x, y, z …… Coordinate axis.

Claims (1)

[Claims] 1. A momentum wheel (4) and two independent axes (x-axis, y-axis) which are substantially orthogonal to the rotation axis (z-axis) of the momentum wheel and orthogonal to each other. A three-axis attitude control device for an artificial satellite, comprising: two sets of torque generating means for generating a predetermined amount of torque, and the two sets of torque generating means each mount one rotor (5, 6). 2 sets of gimbals (5A, 6A), each support shaft (1, 2) of this gimbal is arranged in parallel with the above two axes (x axis, y axis), A three-axis attitude control device for an artificial satellite, characterized in that it is provided with means (13A, 13B) for turning around each.