JP2021014226A - Attitude control device, and method for manufacturing the same - Google Patents

Abstract

To easily provide a reaction wheel having different inertias.SOLUTION: An attitude control device 100 for an artificial satellite includes a reaction wheel 20 and a stator assembly 10 rotatably mounted with the reaction wheel 20, in which the reaction wheel 20 to which any one outer peripheral member 29A selected from a plurality of outer peripheral members 29A and 29B formed so that at least one of a shape and a mass is different is attachably/detachably fixed is configured has a desired inertia.SELECTED DRAWING: Figure 2

Description

The present invention relates to an attitude control device and a method for manufacturing the same, and particularly to a reaction wheel included in the attitude control device.

Conventionally, when an artificial satellite used in outer space changes its attitude, angular momentum exchange type attitude control is performed. The artificial satellite is equipped with an attitude control device, and inertial torque is generated by changing the angular momentum of the rotating body of the attitude control device. This is an attitude control method that changes the attitude of the aircraft by applying the reaction torque of the inertial torque to the aircraft of the artificial satellite. This attitude control is performed by accelerating or decelerating the reaction wheel of the attitude control device. By accelerating or decelerating the rotation of the reaction wheel, the angular momentum changes. By arranging the reaction wheels according to the X-axis, Y-axis, Z-axis, etc. of the artificial satellite body, the artificial satellite body can be oriented in any direction in outer space.

The required inertia of the reaction wheel is determined by the mass of the artificial satellite and the like. When increasing the inertia of the reaction wheel, the thickness of the outer peripheral portion of the reaction wheel is increased, and the mass of the reaction wheel is increased by this. As the mass of the reaction wheel increased, it was necessary to study the structure, including improving the strength of the shaft portion of the reaction wheel and the intermediate portion between the shaft portion and the outer peripheral portion. That is, the reaction wheel was designed for each artificial satellite.

Japanese Unexamined Patent Publication No. 10-71999

However, designing a reaction wheel for each artificial satellite requires design man-hours each time, which is troublesome. In addition, the development cost was incurred.

The present invention has been made to solve the above problems, and is to make it possible to easily supply an attitude control device having different inertia for each artificial satellite so as to be able to meet the demands of different inertia. ..

The attitude control device for an artificial satellite according to the present invention includes a reaction wheel and a stator assembly to which the reaction wheel is rotatably attached, and the reaction wheel has a radius portion provided with a fixed portion and a radius portion. It has an outer peripheral portion provided with a fixing portion corresponding to the fixed portion, and the fixed portion of the radial portion is selected from a plurality of outer peripheral portions in which at least one of the volume and the mass is formed differently. The outer peripheral member is detachably fixed, and the selected outer peripheral member is fixed, so that the reaction wheel is configured to have a desired inertia.

Further, the method for manufacturing an attitude control device for an artificial satellite according to the present invention is a method for manufacturing an attitude control device used for an artificial satellite including a reaction wheel and a stator assembly to which the reaction wheel is rotatably attached. The process of manufacturing the stator assembly to which the reaction wheel is attached, the step of manufacturing the radial member that constitutes the reaction wheel by providing the fixed portion, and the fixing portion corresponding to the fixed portion are provided, and the volume is increased. , And a step of producing a plurality of outer peripheral members having different masses, a step of selecting an outer peripheral member constituting a desired inertia reaction wheel from the plurality of outer peripheral members, and fixing of the selected outer peripheral member. It includes a step of assembling the reaction wheel by fixing the portion to the fixed portion of the radial member, and a step of rotatably fixing the assembled reaction wheel to the stator assembly.

In the attitude control device according to the present invention, an outer peripheral member selected from a plurality of outer peripheral portions in which at least one of the volume and the mass of the reaction wheel is formed is detachably fixed. Therefore, the inertia of the desired reaction wheel can be obtained. Therefore, it is possible to supply an inertial attitude control device that differs for each artificial satellite in a short period of time and at low cost.

In the method for manufacturing an attitude control device according to the present invention, a step of manufacturing a plurality of outer peripheral members in which at least one of the volume and the mass of the reaction wheel is different, and a reaction wheel of a desired inertia from the plurality of outer peripheral members. It is provided with a step of selecting an outer peripheral member constituting the above. Therefore, the reaction wheel of the desired inertia can be manufactured by the outer peripheral member constituting the reaction wheel of the desired inertia. Therefore, it is possible to supply an inertial attitude control device that differs for each artificial satellite in a short period of time and at low cost.

It is a side view of the attitude control device which concerns on embodiment of this invention. It is a side sectional view in the state which removed the cover of the attitude control device of FIG. It is an enlarged view of part A of FIG. FIG. 3 is an enlarged view of part A of FIG. 2 showing a case where an outer peripheral member having a shape different from that of FIG. 3 is attached.

Embodiment The attitude control device 100 according to the embodiment of the present invention will be described with reference to FIGS. 1 to 3. FIG. 1 is a side view of the attitude control device 100 according to the embodiment of the present invention. Further, FIG. 2 is a side sectional view of a plane passing through the central axis of the attitude control device 100 in a state where the cover of the attitude control device 100 of FIG. 1 is removed. Further, FIG. 3 is an enlarged view of part A of FIG.
As shown in FIG. 1, the attitude control device 100 includes a stator assembly 10 and a cover 50 fixed to the stator assembly 10. FIG. 2 shows the internal configuration of the attitude control device 100, and the attitude control device 100 further includes a reaction wheel 20 rotatably attached to the stator assembly 10.

The stator assembly 10 is a fixing portion of the attitude control device 100 fixed to the body of the artificial satellite. Further, as will be described later, the stator assembly 10 generates an electromagnetic force that brings a rotational force to the reaction wheel 20.
The reaction wheel 20 is a member that controls the attitude of the artificial satellite's airframe according to the rotational state. The rotation of the reaction wheel 20 is accelerated or decelerated by the electromagnetic force generated by the stator assembly 10. The attitude of the artificial satellite is controlled by changing the angular momentum of the reaction wheel 20.
The shaft 40 is a member that holds the reaction wheel 20 in the stator assembly 10.
The cover 50 is a member that covers the reaction wheel 20. The cover 50 prevents other members outside the attitude control device from coming into contact with the reaction wheel 20 which is a rotating object.

Next, each of the above-mentioned constituent members will be described.
The stator assembly 10 has a main body member 11 fixed to the body of the artificial satellite, and a shaft member 16 fixed to the main body member 11.

The main body member 11 includes a substantially circular disk portion 12, a substantially cylindrical outer peripheral cylindrical portion 13, and a substantially cylindrical stator portion 14. The main body member 11 has a bottomed cylindrical shape with one end opened.
The disk portion 12 is a substrate portion of the main body member 11.
The outer peripheral cylindrical portion 13 is a member having a substantially cylindrical shape. The outer peripheral cylindrical portion 13 is provided perpendicular to the disc portion 12 so that the central axes of the two are aligned with the entire circumference of the outer peripheral end portion of the disc portion 12.
The stator portion 14 is a member having a substantially cylindrical shape, and a plurality of coils 15 are arranged at equal intervals in the circumferential direction. The stator portion 14 is coaxially arranged on the entire circumference of a portion of the disk portion 12 near the outer peripheral end portion on the opposite surface to the surface on which the outer peripheral cylindrical portion 13 is provided, with the central axes of both aligned. It is provided perpendicular to the portion 12. The current of the plurality of coils 15 is controlled by a control unit (not shown) to generate an electromagnetic force.
That is, the main body member 11 is configured by providing an outer peripheral cylindrical portion 13 on one surface of the disk portion 12 and a stator portion 14 on the other surface.

The shaft member 16 includes a shaft base portion 17, a shaft cylindrical portion 18, a bearing 19, a shaft 40 that holds the reaction wheel 20 on the stator assembly 10, and a nut 42 that fixes the reaction wheel 20 to the shaft 40. Includes.
The shaft base portion 17 is a member having a substantially disk shape and is provided with a hole in the central portion.
The shaft cylindrical portion 18 is a substantially cylindrical member having both ends opened and a shaft center hole 18a provided in the central portion. The shaft cylindrical portion 18 is coaxially arranged and fixed to the central portion of one surface of the shaft base portion 17 so that the central axes of both are aligned with each other. The shaft base portion 17 and the shaft cylindrical portion 18 are integrally formed.
The bearing 19 is a well-known ball bearing, and is arranged inside the shaft cylindrical portion 18. The bearing 19 rotatably holds the reaction wheel 20 via the shaft 40. Two bearings 19 are arranged in the central axial direction of the shaft member 16 so that the reaction wheel 20 is stably held via the shaft 40.

The shaft member 16 is fixed at the center of the surface opposite to the surface of the disk portion 12 where the outer peripheral cylindrical portion 13 is provided, with the central axes of the shaft member 16 and the disk portion 12 aligned. That is, the shaft member 16 and the stator portion 14 are provided on the same side surface of the disk portion 12.

The reaction wheel 20 is a member rotatably attached to the stator assembly 10, and has a radial member 21 and a ring-shaped outer peripheral member 29 fixed to the outer peripheral portion of the radial member 21.

The radial member 21 includes a central portion 22 fixed to the shaft 40, an intermediate portion 24 arranged on the outer peripheral side of the central portion 22, and an outer edge portion 25 arranged on the outer peripheral side of the intermediate portion 24. It is integrally formed including. The radial member 21 is made of a magnetic material.

A central hole 23 is provided at the center of the disk shape. The reaction wheel 20 is fixed to the shaft 40 inserted in the center hole 23 with a nut 42, and is rotatably attached to the stator assembly 10 via the bearing 19.
A ring-shaped intermediate portion 24 is provided on the entire outer circumference of the central portion 22. The intermediate portion 24 extends from the central portion 22 to the outer peripheral side and in a direction away from the central portion 22 in the axial direction.

An outer edge portion 25 is provided at the outer peripheral end portion of the intermediate portion 24. The outer edge portion 25 has a cylindrical shape. The outer edge portion 25 has the outer peripheral end portion of the intermediate portion 24 as a base end, and the reaction wheel 20 is in the direction opposite to the direction in which the intermediate portion 24 extends with respect to the central portion 22 in the central axis direction of the reaction wheel 20. Extends parallel to the central axis of. Further, a magnet 27 is fixed to the outer peripheral side surface of the end portion connected to the intermediate portion 24 of the outer edge portion 25 by a magnet fixing piece 28 and a fixing tool such as a screw. Further, a fixed portion 26 to which the outer peripheral member 29 described later is fixed is provided at the end portion of the outer edge portion 25 opposite to the end portion on which the magnet 27 is arranged.

A stator portion 14 is inserted between the outer edge portion 25 and the outer peripheral member 29 with a gap. The magnet 27 incorporated in the outer edge portion 25 in a state where the stator assembly 10 and the reaction wheel 20 are assembled is a coil 15 arranged in the stator portion 14 in the central axis direction of the stator assembly 10. It is located almost in the center. That is, the magnet 27 faces the coil 15 with a slight gap in between. With this arrangement, the reaction wheel 20 is rotated by efficiently utilizing the electromagnetic force generated in the coil 15.

FIG. 3 is an enlarged view of the A portion of FIG. 2, showing a state in which the outer peripheral member 29A is fixed to the outer edge portion 25. The outer peripheral member 29A is provided with a fixing portion 30 corresponding to the fixed portion 26 at the end of the outer peripheral member 29A. The fixing portion 30 is joined to the fixed portion 26, and the outer peripheral member 29A is fixed to the outer edge portion 25. The outer peripheral member is a member that forms a part of the reaction wheel 20 and adjusts the inertia of the entire reaction wheel 20 to a desired inertia. A convex portion 31 facing the coil 15 arranged on the stator portion 14 is provided on the inner surface side of the outer peripheral member 29A with a slight gap. By arranging the convex portion 31 close to the coil 15, the magnetic flux generated by the coil 15 can be concentrated and the magnetic force can be efficiently used.

FIG. 4 is an enlarged view of part A of FIG. 2 showing a case where the outer peripheral member 29B as another form having a shape different from that of the outer peripheral member 29A of FIG. 3 is mounted. A plurality of outer peripheral members 29A, 29B, etc., which are formed differently in at least one of the shape and the mass, are prepared in advance so that the inertia of the reaction wheel 20 becomes the desired inertia. The outer peripheral member 29B is formed by changing the radial dimension, and the outer peripheral member 29B shown in FIG. 4 has a shape that greatly projects toward the outer peripheral side with respect to the outer peripheral member 29A shown in FIG. Is formed in. As a result, the outer peripheral member 29B has a larger mass than the outer peripheral member 29A, and the inertia of the reaction wheel 20 also increases.

Further, the dimensions or the shape in the central axis direction may be changed. Further, the inertia of the reaction wheel 20 may be changed by changing the material without changing the shape of the outer peripheral member 29.

In addition, as another form of the outer peripheral member 29, the mass of the outer peripheral member 29 may be changed by providing a hollow portion inside without changing the outer shape, and the inertia of the reaction wheel 20 may be changed. When the small hollow portion is formed inside the outer peripheral member 29, the inertia of the reaction wheel 20 is larger than when the large hollow portion is formed. Further, even when a hollow portion having the same size is formed, when the position of the hollow portion is formed closer to the inner circumference in the outer peripheral member 29, the inertia of the reaction wheel 20 is larger than when the hollow portion is formed closer to the outer circumference. .. When the hollow portion is provided inside the outer peripheral member 29, the outer shape does not change, so that it does not interfere with other parts. That is, the inertia of the reaction wheel 20 can be changed by providing a hollow portion inside the outer peripheral member 29 by changing at least one of the size and the position.

A fixing portion 30 having the same shape corresponding to the fixed portion 26 of the outer edge portion 25 is provided on any of the plurality of outer peripheral members 29 (29A, 29B, etc.) having different shapes and at least one of the masses. .. Therefore, any outer peripheral member 29 (29A, 29B, etc.) can be fixed to the fixed portion 26. Therefore, one of the outer peripheral members 29 (29A, 29B, etc.) is selected from the plurality of outer peripheral members 29 (29A, 29B, etc.) having different shapes and at least one of the masses, and the fixed portion 26 is used. By fixing, the inertia of the desired reaction wheel 20 can be configured.

The shaft 40 is inserted into the inner race portion of the bearing 19 arranged in the shaft center hole 18a of the shaft cylindrical portion 18 of the stator assembly 10. The tip of the shaft 40 is passed through the center hole 23 of the reaction wheel 20, and the reaction wheel 20 is fixed to the shaft 40 by fastening a nut or the like.

When the reaction wheel 20 is rotationally balanced, the unbalance amount is measured with the radial member 21 and the outer peripheral member 29 assembled. According to the measured unbalance amount, the outer edge portion, which is the outer peripheral portion of the radial member 21, is drilled or cut, and the rotational balance is adjusted.

Next, the operation of the attitude control device 100 will be described.
When the attitude control of the artificial satellite is started by a control device (not shown) provided in the artificial satellite, a current is passed through the coil 15 arranged in the stator assembly 10 of the attitude control device 100 according to the attitude control amount. Is done. According to a well-known principle, a rotational force is generated in the reaction wheel 20 by the relationship between the magnetic field generated by passing an electric current through the coil 15 and the magnet 27 provided in the reaction wheel 20. When the rotation of the reaction wheel 20 accelerates with respect to the rotation state of the reaction wheel 20 before the start of control, the angular momentum of the reaction wheel 20 changes. The attitude of the artificial satellite's airframe changes due to the reaction torque when the angular momentum changes. Further, when the body of the artificial satellite is changed in the opposite direction to the above, the reaction wheel 20 is decelerated, that is, accelerated in the opposite direction, and the angular momentum of the reaction wheel 20 is changed in the opposite direction to the above.

Next, a method of selecting the outer peripheral member 29 according to the inertia of the reaction wheel 20 will be described.
As described above, the outer peripheral member 29 constituting the reaction wheel 20 of the present invention is prepared in advance with a plurality of outer peripheral members 29 (29A, 29B, etc.) formed having at least one of a different shape and mass. By selecting and assembling the optimum outer peripheral member 29 from the outer peripheral members 29, the inertia of the reaction wheel 20 is configured to be a desired inertia.

First, the inertia required for the reaction wheel 20 is obtained from the mass of the entire body of the artificial satellite, the constituent devices, and the like. Then, the inertia required for the outer peripheral member 29 is obtained by the following equation.
[Inertia of outer peripheral member 29] = [Inertia of reaction wheel 20]-[Inertia of radial member 21]
In addition, in the inertia of the above-type radial member 21, the shaft 40 and its fixing member necessary for assembling the attitude control device 100, the inner race of the bearing 19, a part of the bearing ball, and the reaction wheel 20 are assembled. It is calculated including the necessary inertia such as screws and other fixtures.
After obtaining the inertia of the outer peripheral member 29, the outer peripheral member 29 having a mass obtained from the distance from the rotation center of the outer peripheral member 29 is selected so as to match the calculated inertia.

In the attitude control device for an artificial satellite according to the embodiment of the present invention, the reaction wheel has a removable outer peripheral member selected from a plurality of outer peripheral portions formed having at least one of a different volume and mass. It is fixed to. By fixing the selected outer peripheral member, the reaction wheel is configured to have the desired inertia.

According to the attitude control device according to the present invention, the inertia of a desired reaction wheel can be obtained only by selecting and fixing the optimum outer peripheral member of the inertia. Therefore, it is possible to supply a different inertia attitude control device for each artificial satellite in a short period of time.

According to the attitude control device according to the present invention, the inertia of a desired reaction wheel can be obtained only by selecting and fixing the optimum outer peripheral member of the inertia. Therefore, it is possible to supply an inertial attitude control device that differs for each artificial satellite with a small number of development man-hours and a low cost.

10 stator assembly, 20 reaction wheels, 21 radius members,
26 Fixed part, 29A, 29B outer peripheral member, 30 Fixed part,
100 Attitude control device

Claims (2)

A reaction wheel (20) and a stator assembly (10) to which the reaction wheel (20) is rotatably attached are provided.
The reaction wheel (20) has a radial member (21) provided with a fixed portion (26) and an outer peripheral member (29) provided with a fixed portion (30) corresponding to the fixed portion (26). ) And
A plurality of outer peripheral members (29A, 29B) having at least one of a different shape and mass formed in the fixed portion (26) of the radial member (21) and constituting the outer peripheral member (29). ), Any one of the outer peripheral members (29A or 29B) is detachably fixed and fixed.
An attitude control device for an artificial satellite, wherein the reaction wheel (20) is configured to have a desired inertia by fixing the selected outer peripheral member (29A or 28B). A method of manufacturing an attitude control device used for an artificial satellite including a reaction wheel (20) and a stator assembly (10) to which the reaction wheel (20) is rotatably attached.
The process of manufacturing the stator assembly (10) to which the reaction wheel (20) is attached, and
A step of manufacturing a radial member (21) which is provided with a fixed portion (26) and constitutes the reaction wheel (20), and
A step of producing a plurality of outer peripheral members (29A, 29B) in which a fixing portion (30) corresponding to the fixed portion (26) is provided and at least one of a volume and a mass is different.
A step of selecting any one of the outer peripheral members (29A or 29B) constituting the reaction wheel (20) of the desired inertia from the plurality of outer peripheral members (29A, 29B).
A step of assembling the reaction wheel (20) by fixing the fixed portion (30) of the selected outer peripheral member (29A or 29B) to the fixed portion (26) of the radial member (21).
A method for manufacturing an attitude control device for an artificial satellite, comprising a step of rotatably attaching the assembled reaction wheel (20) to the stator assembly (10).

Images