JP2002321700A - Satellite structure panel damping method and damping device - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To provide a vibration damping device for a satellite structure panel which is lightweight and has high damping performance. SOLUTION: Vibration detecting means for detecting vibration of a satellite structure panel, vibrating means for applying vibration to the satellite structure panel, and detecting the vibration generated in the satellite structure panel based on a detection signal of the vibration detecting means. And a control means for causing the vibration generating means to generate a canceling vibration.
Further, the vibration detecting means is a piezoelectric sensor, and the vibrating means is a piezoelectric actuator.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vibration damping method and a vibration damping device for suppressing a vibration generated in a satellite structure panel as a component of an artificial satellite.

[0002]

2. Description of the Related Art When a satellite is launched by a rocket, acoustic vibration is generated inside a fairing or the like in which the satellite is housed. When the main body of the satellite is vibrated by such an acoustic vibration, various mounted devices mounted on the satellite structure panel may be damaged by the vibration. It is necessary to reduce the vibration level to a level at which the mounted device does not fail.

As a conventional vibration damping device, for example, there is a device disclosed in Japanese Patent Application Laid-Open No. 63-94832 by the present applicant. This device absorbs bending vibration generated in the satellite structure panel due to acoustic vibration as strain energy generated in the viscoelastic material attached to the satellite structure panel in a plane,
By attenuating inside the viscoelastic material and converting it to heat energy to dissipate it, the vibration of the satellite structure panel, that is, bending vibration, is absorbed and the amplitude of the vibration is reduced.

[0004]

However, in such a conventional device, the more the viscoelastic material is required to improve the vibration damping performance, the more the weight of the satellite body inevitably increases. There was a problem that it would. Moreover, since a vacuum environment is created in outer space, gas is generated from the viscoelastic material,
It was feared that it would adversely affect the onboard equipment.

An object of the present invention is to solve such problems and to provide a vibration damping device for a satellite structure panel which is lighter and has higher vibration damping performance than conventional devices.

[0006]

According to a first aspect of the present invention, there is provided a vibration damping device for a satellite structure panel, comprising: a vibration detecting means for detecting a vibration of the satellite structure panel; And control means for causing the vibrating means to generate a vibration that cancels the vibration generated in the satellite structure panel based on a detection signal of the vibration detecting means.

According to a second aspect of the present invention, in the vibration damping device for a satellite structure panel according to the first aspect, the vibration detecting means comprises a piezoelectric sensor, and the vibrating means comprises a piezoelectric actuator.

According to a third aspect of the present invention, in the vibration damping device for a satellite structure panel according to the second aspect, the piezoelectric sensor and the piezoelectric actuator are formed in a planar shape that can be mounted on the satellite structure panel by surface contact. Features.

According to a fourth aspect of the present invention, in the vibration damping device for a satellite structure panel according to the second aspect, the piezoelectric sensor and the piezoelectric actuator are vertically stacked.

According to a fifth aspect of the present invention, the vibration of the satellite structure panel is detected by a piezoelectric sensor and provided on the satellite structure panel via control means based on the detected voltage. It is characterized in that the piezoelectric actuator generates a vibrating force in a direction to cancel the vibration, thereby actively suppressing the vibration of the satellite structure panel.

According to a sixth aspect of the present invention, in the vibration control method for a satellite structure panel according to the fifth aspect, the piezoelectric actuator includes one inflection point of the vibration mode on the satellite structure panel and the other inflection point. It is characterized in that it is disposed between.

According to a seventh aspect of the present invention, in the method for damping a satellite structure panel according to the fifth aspect, the piezoelectric actuator includes an inflection point of a vibration mode on the satellite structure panel and a non-vibration part near the inflection point. 6. The method according to claim 5, wherein the satellite structure panel is disposed between the satellite structure panel.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiment 1 The present invention will be described with reference to FIGS. 1 to 4 showing the first embodiment. FIG. 1 is a cross-sectional view showing a state where the vibration damping device is mounted on the satellite structure panel, FIG. 2 is a plan view showing a state where the vibration damping device is mounted on the satellite structure panel, FIG. FIG. 4 is a diagram illustrating the operation of the vibration damping device.

In FIG. 1 to FIG.
The two satellite structural panels 2 are other satellite structural panels joined to both edges of the satellite structural panel 1, and 3 is a vibration damping device 3 bonded to the surface of the satellite structural panel 1. The vibration damping device 3 includes a piezoelectric sensor 4 as vibration detecting means for detecting vibration generated in the satellite structure panel 1 and a vibration generating means for applying vibration to cancel the vibration area of the satellite structure panel 1. A piezoelectric actuator 5, an elastic resin 6 for integrally molding the piezoelectric sensor 4 and the piezoelectric actuator 5, and the satellite structure panel 1 based on a voltage signal as a detection signal from the piezoelectric sensor 4. And a controller 7 as a control means for causing the piezoelectric actuator 5 to generate vibration that cancels the vibration generated in the piezoelectric actuator 5.

The piezoelectric sensor 4 and the piezoelectric actuator 5 are each formed in a planar shape, and are integrally molded with an elastic resin 6 with the piezoelectric actuator 5 superimposed on the piezoelectric sensor 4. I have. In this example, the disc-shaped piezoelectric actuator 5 is also superimposed on the disc-shaped piezoelectric sensor 4, but the piezoelectric actuators 5 may also be configured so that both are vertically inverted.

In any case, the piezoelectric sensor 4 and the piezoelectric actuator 5 mounted on the satellite structure panel 1 can be adhered to a required surface of the satellite structure panel 1 which is expected to generate vibration by surface contact. For example, it is preferable to form a flat disk shape as shown in FIG. The planar shape of the piezoelectric sensor 4, the piezoelectric actuator 5, and the like can be relatively freely formed into a desired shape irrespective of its shape such as a square, a rectangle, a circle, and an ellipse. In this case, the disk-shaped piezoelectric actuator 5 is configured to contract or expand in the diameter direction.

Referring to FIGS. 2 and 4, the operation of the vibration damping device will be described. When vibration (bending vibration) occurs in the satellite structure panel 1, the vibration is detected as a voltage signal by the piezoelectric sensor 4 and is input to the controller 7. The controller 7 controls the piezoelectric actuator 5 to generate a vibrating force in a direction to cancel the vibration based on the voltage signal, and to cancel the vibration by the vibration due to the vibrating force.

For example, as shown in FIG. 4, when the satellite structure panel 1 bends upward so as to be convex in FIG. 4, a piezoelectric sensor 4 provided in advance in the relevant portion of the satellite structure panel 1 is provided.
Then, a distortion in the extension direction of the piezoelectric sensor 4 occurs. When this distortion, that is, stress occurs in the piezoelectric sensor 4, a voltage corresponding to the pressure is generated by the piezoelectric effect. Since this voltage signal becomes proportional to the average strain rate in the surface portion (vibration region) of the satellite structure panel 1 in the area covered by the piezoelectric sensor 4 via the resistor, the voltage signal is inverted and amplified. By applying the piezoelectric actuator 5 to the piezoelectric actuator 5, distortion in the stress direction can be generated in the piezoelectric actuator 5. Thereby, the bent portion of the satellite structure panel 1 includes:
A compressive force is applied in the directions indicated by arrows A, A, and upward deflection of the satellite structure panel 1 is suppressed.

On the other hand, when the satellite structure panel 1 bends so as to protrude in the opposite direction (downward in the figure) to the above case, the voltage signal from the piezoelectric sensor 4 is reversed. Because of the sign, the piezoelectric actuator 5 generates a strain in the tensile direction via the controller 7, contrary to the above case. As a result, a tensile force is generated in the satellite structure panel 1 in a direction opposite to the direction indicated by arrows A, A, and the downward bending of the satellite structure panel 1 is suppressed.

Thus, the vibration damping device 3 of the first embodiment actively suppresses the vibration generated in the satellite structure panel 1 unlike the conventional vibration damping device. In the vibration damping device 3 according to the first embodiment, since the piezoelectric sensor 4 and the piezoelectric actuator 5 are configured to be superposed on the same surface, collocation is established, and the vibration mode is not directly handled. A circuit can be configured, and vibration can be suppressed in a wide frequency range. Further, since the controller 7 can be configured as a relatively simple control circuit of a collocated type, it is possible to provide a lightweight and inexpensive vibration damping device 3.

Further, as shown in FIGS. 2 and 4, the piezoelectric actuator 5 of the vibration damping device 3 according to the first embodiment moves from one inflection point P1 of the vibration mode generated in the satellite structure panel 1 to the inflection point P1. And is arranged to extend to the vibration region between the other inflection point P2 opposite to. With such arrangement (arrangement), the generated vibration can be effectively suppressed.

The vibration region does not always occur at one position in the center of the satellite structure panel 1 as shown in the first embodiment, but the position and number of vibration sources, the type and size of vibration. For example, it may occur at a plurality of locations. However, since such a vibration region is assumed in advance in the design of the satellite, a necessary vibration damping device 3 is appropriately provided so as to generate a vibration that cancels the vibration for each assumed vibration region.
By disposing the above, the satellite structure panel 1 can be effectively damped as a whole.

Embodiment 2 FIG. In the second embodiment, the vibration damping device 3 in which the piezoelectric sensor 4 and the piezoelectric actuator 5 are formed separately from the vibration damping device 3 described in the first embodiment.
Is not disposed between one inflection point P1 of the vibration mode and the other inflection point P2 opposite thereto as shown in FIG. 4, but a required inflection point of the vibration mode and a required non-vibration part This is a mode that is appropriately disposed between the two. Hereinafter, this will be described with reference to FIGS. FIG. 5 is a cross-sectional view showing a state where the vibration damping device 3 is mounted on the satellite structure panel, FIG. 6 is a plan view showing a state where the vibration damping device is mounted on the satellite structure panel, and FIG. FIG.

For example, when a vibration region is assumed to be generated in the center of the satellite structure panel 1 as shown in FIG. 4, as shown in FIGS. 5 and 6, a required inflection point PX of the vibration region and the corresponding inflection point PX are determined. It is arranged between a portion near the inflection point PX where vibration is relatively small, and preferably a portion where vibration hardly occurs (hereinafter, such a portion is referred to as a non-vibration portion). In this example, paying attention to the fact that the joint 8 between the satellite structure panel 1 and the other satellite structure panels 2 and 2 is a vibration-free part where vibration is relatively unlikely to occur, the required part of the joint 8 is designated as a vibration-free part. Treated as parts. The piezoelectric actuator 5 is firstly arranged so that the piezoelectric sensor 4 extends in series from the joint portion (8) toward the inflection point PX.

As described above, by disposing the piezoelectric actuator 5 and the piezoelectric sensor 4 constituting the vibration damping device 3 at positions close to each other (the controller 7 is not shown), for example, the satellite structure panel 1, when a downwardly convex bending vibration occurs in FIG.
Is generated in proportion to the distortion generated in the piezoelectric actuator 5, the voltage signal obtained from the piezoelectric sensor 4 is inverted, amplified, and applied to the piezoelectric actuator 5. Is generated, and a compressive force in the directions indicated by arrows A and A can be generated.

On the other hand, when the satellite structure panel 1 bends convexly in the opposite direction (upward in FIG. 7) to the above case, the voltage signal from the piezoelectric sensor 4 has the opposite sign to the above case. Therefore, the piezoelectric actuator 5 generates a strain in the tensile direction via the controller 7 (not shown), contrary to the above case. As a result, a tensile force is generated in the satellite structure panel 1 in a direction opposite to the direction indicated by the arrows A, A, and the upward bending of the satellite structure panel 1 is suppressed. Thereby, the vibration of the satellite structure panel 1 can be actively suppressed.

The vibration damping device 3 shown in the second embodiment
Is a configuration in which the piezoelectric actuator 5 and the piezoelectric sensor 4 are arranged close to each other in a side-by-side state, so that in a high-dimensional vibration mode, distortion generated between the piezoelectric sensor 4 and the piezoelectric actuator ground # 5 is not proportional. However, in this case, a required correction circuit is required. For example, a circuit is needed which filters out the voltage signal of the piezoelectric sensor 4 and extracts only the frequency component in the vibration mode to be controlled. Of course, also in the vibration damping device 3 according to the second embodiment, the piezoelectric actuator 5 and the piezoelectric sensor 4 are configured to overlap with each other, so that the collocated control described in the first embodiment can be performed. The operation and effect of the present invention can be obtained.

[0028]

According to the first to seventh aspects of the present invention, vibrations generated in the satellite structure panel are efficiently suppressed by generating vibrations that cancel the vibrations in response to the generated vibrations. can do. Further, the vibration response level of the resonance frequency at the time of launching a satellite or the like can be reduced, and the failure of the on-board equipment can be prevented.

According to each of the first to fourth aspects of the present invention,
Since the weight of the vibration damping device can be reduced as compared with a conventional vibration damping device using a viscoelastic material, it is possible to contribute to the weight reduction of the satellite.

According to the fifth to seventh aspects of the invention, it is possible to effectively suppress the vibration generated in the satellite structure panel.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing a state where a vibration damping device according to a first embodiment is mounted on a satellite structure panel.

FIG. 2 is a plan view showing a state where the vibration damping device according to the first embodiment is mounted on a satellite structure panel.

FIG. 3 is a cross-sectional view of the vibration damping device according to the first embodiment.

FIG. 4 is an explanatory diagram of an operation of the vibration damping device according to the first embodiment.

FIG. 5 is a cross-sectional view illustrating a state where the vibration damping device according to the second embodiment is mounted on a satellite structure panel.

FIG. 6 is a plan view showing a state where the vibration damping device according to the second embodiment is mounted on a satellite structure panel.

FIG. 7 is an explanatory diagram of an operation of the vibration damping device according to the second embodiment.

[Explanation of symbols]

1, 2 satellite structure panel, 3 vibration damping device, 4 piezoelectric sensor (vibration detecting means), 5 piezoelectric actuator (vibrating means), 6 resin, 7 controller (control means).

Claims (7)

[Claims] 1. A vibration detecting means for detecting a vibration of a satellite structure panel, a vibration generating means for applying a vibration to the satellite structure panel, and the vibration generated in the satellite structure panel based on a detection signal of the vibration detecting means. Control means for causing the vibration means to generate a vibration that cancels the vibration. 2. The vibration damping device for a satellite structure panel according to claim 1, wherein the vibration detecting means is constituted by a piezoelectric sensor, and the vibrating means is constituted by a piezoelectric actuator. 3. The vibration damping device for a satellite structure panel according to claim 2, wherein the piezoelectric sensor and the piezoelectric actuator are formed in a planar shape that can be mounted on the satellite structure panel by surface contact. 4. The vibration damping device for a satellite structure panel according to claim 2, wherein the piezoelectric sensor and the piezoelectric actuator are vertically stacked. 5. A vibration of a satellite structure panel is detected by a piezoelectric sensor, and based on the detected voltage, a vibrating force for canceling the vibration is generated in a piezoelectric actuator provided on the satellite structure panel via a control means. A vibration control method for the satellite structure panel, wherein the vibration of the satellite structure panel is actively suppressed. 6. The satellite structure according to claim 5, wherein the piezoelectric actuator is disposed between one inflection point of the vibration mode on the satellite structure panel and the other inflection point opposed to the vibration mode. Panel damping method. 7. The satellite according to claim 5, wherein the piezoelectric actuator is disposed between an inflection point of a vibration mode on the satellite structure panel and a non-vibration part near the inflection point. How to control the structure panel.