JP2891531B2 - Shaking table controller - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a shaking table controller that performs suitable control by using an electro-hydraulic shaking table system including a shaking table body and a shaking table controller. .

[Prior Art] FIGS. 2 and 4 show a conventional technique.

FIG. 2 is a block diagram of a conventional shaking table system, and FIG. 4 is a diagram illustrating an example of frequency characteristics of shaking table displacement control in a conventional method.

The conventional electro-hydraulic shaking table system is composed of a shaking table controller and a shaking table main body, gives a target displacement value of the shaking table main body as a target waveform, and is attached to the displacement target value and the shaking table main body. Control is performed so that the outputs of the displacement sensors become equal.

For this purpose, the shaking table controller inputs a deviation between the target waveform and the displacement sensor, that is, a deviation of the displacement, and determines an operation amount to the shaking table main body so as to make the deviation zero.

In obtaining the manipulated variable from this deviation, a PID control method has been often used in general.

On the other hand, with the rapid development of computing technology,
Instead of the D control method, the optimal control method is attracting attention as a higher-performance control method.By replacing the PID control method with the optimal control method, improvements such as improvement in frequency characteristics and reduction in distortion factor have been made. ing.

[Problems to be Solved by the Invention] Immediately replacing the PID control method with the optimal control means as a control method used for the shaking table control device can improve the control performance.
The problem of hardware modification and adjustment due to completely replacing the analog shaking table controller that has been controlling with the digital shaking table controller that performs optimal control, and the past performance of PID control for failure troubles There is also a problem that it is difficult for the user to accept it.

[Means for Solving the Problems] The conventional shaking table control device based on PID control is left as it is, and a shaking table control device based on optimal control is mounted as a higher-order shaking table control device.

In other words, the conventional shaking table control system using PID control takes the target displacement value as input and outputs the detection signal of the displacement sensor, but creates a shaking table control device using the optimal control method with this system as a new control object. Then, the output of the device is input as a displacement target value to the conventional shaking table controller.

At the same time, two types of inputs to the shaking table control device by the conventional PID control can be selected: a conventional displacement target value and an output from the upper shaking table control device.

That is, the present invention relates to a vibration table system comprising an analog vibration table control device and a vibration table body, wherein: (A) a vibration which receives a displacement sensor signal of the vibration table system and acts as a higher-order phase lead compensator; The table optimal control device 1 is arranged in front of the analog type shaking table control device 5. (B) The vibration table optimal control device 1 receives a signal from the target displacement value input terminal 12 via the first subtractor 2. Signal and a feedback signal from the displacement sensor 11 of the shaking table body,
(C) The switch 3 receives a signal from the shaking table optimal control device 1 or the displacement target value input terminal 12 by a switching operation, and outputs the signal to the second subtractor 4. (D) The analog type shaking table controller 5 receives a signal from the changeover switch 3 and a feedback signal from the displacement sensor 11 of the shaking table body via the second subtractor 4. (E) When oscillation occurs in the shaking table optimal control device 1, the signal from the target displacement value input terminal 12 is subtracted by the switching operation of the changeover switch 3 by the second subtraction. The signal is output to an analog type shaking table control device 5 through the device 4.

[Operation] The shaking table control device designed by the above-described optimal control method functions as a higher-order phase lead compensator, and therefore, the frequency characteristics of the shaking table and the distortion rate of the reproduced waveform are improved.

On the other hand, if a problem such as oscillation occurs,
The input of the shaking table controller by PID control can be used by switching to the conventional displacement target value.

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram of a shaking table system according to a first embodiment of the present invention, and FIG. 3 is a diagram showing frequency characteristics of shaking table displacement control according to the present invention.

The shaking table system according to the present invention includes a higher-order shaking table controller 1,
It is composed of subtracters 2 and 4, a changeover switch 3, a conventional shaking table controller 5, a servo amplifier 6, a hydraulic source 7, a servo valve 8, a hydraulic cylinder 9, a shaking table body 10, a displacement sensor 11, and the like. Control is performed so that the target displacement value input from the target displacement value input terminal 12 and the displacement of the shaking table body 10 are equal.

That is, the changeover switch 3 is normally on the B side,
The difference between the target displacement value applied to the target displacement value input terminal 12 and the displacement sensor 11 is obtained by the subtractor 2.

This deviation is input to the upper shaking table controller 1, and the output is applied to the displacement target value input terminal 13 of the conventional shaking table controller 5.

In the following, a new position deviation is obtained by the subtractor 4 and input to the conventional shaking table control device 5, just like the conventional example shown in FIG.

The output of the control device 5 is power-amplified by the servo amplifier 6 and becomes a command to the servo valve 8.

The movement of the servo valve 8 drives the vibration table main body 10 connected to the hydraulic cylinder 9.

The displacement of the shaking table body 10 is detected by the displacement sensor 11 and sent to the subtracters 2 and 4 as a position feedback signal.

On the other hand, if a problem such as oscillation occurs, the changeover switch 3 is switched to the A side so that the configuration can be completely returned to the configuration of the conventional shaking table system.

FIG. 3 shows an example of the effect of improving the frequency characteristics of the shaking table control according to the present invention.

The frequency characteristic in FIG. 3 is about 15 Hz at the point of -3 dB, and the gain characteristic is flat.

On the other hand, the frequency characteristic of the conventional method shown in FIG.
Since it is Z and a peak is generated at 6 Hz, it is understood that damping is also bad.

[Effects of the Invention] As described above, according to the present invention, (1) a shaking table optimal control device designed by considering a shaking table system including a conventional shaking table control device and a shaking table as a new control object; By adopting a configuration in which the output is inputted to the above-mentioned conventional shaking table control device, the frequency characteristic in the displacement control of the shaking table is improved so as to be flat up to a high frequency range.

(2) At the same time, the distortion factor of the reproduced waveform is improved due to the extension of the frequency characteristics.

(3) Therefore, for an elastic load that allows trial excitation,
After the excitation characteristics are identified by trial excitation, the input compensation control, which compensates for the acceleration waveform using the inverse transfer characteristics, is combined with the conventional control device. By using the control means according to the present invention for a test in which vibration cannot be performed, a wider range of vibration test can be performed.

[Brief description of the drawings]

FIG. 1 is a block diagram of a shaking table system according to a first embodiment of the present invention, FIG. 2 is a block diagram of a conventional shaking table system, and FIG. 3 is a diagram showing frequency characteristics of shaking table displacement control according to the present invention. FIG. 4 is a diagram showing an example of a frequency characteristic of shaking table displacement control in a conventional method. (Explanation of reference numerals) 1 upper-level shaking table controller (optimum shaking table controller) 2... 1st subtracter 3... Changeover switch 4. 2nd subtracter 5. Control device (analog type shaking table control device) 6 Servo amplifier 7 Hydraulic power source 8 Servo valve 9 Hydraulic cylinder 10 Shaking table body 11 Displacement sensor 12 …… Displacement target value input terminal of the host shaking table controller, 13 …… Displacement target value input terminal of the conventional shaking table controller.

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A 1-227038 (JP, A) JP-A 60-207908 (JP, A) JP-A 63-273902 (JP, A) JP-A 56-207 67403 (JP, A) JP-A-57-43268 (JP, A) JP-A-59-33503 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) G05D 19/02 G04B 7 / 02

Claims (1)

(57) [Claims] 1. A shaking table system comprising an analog shaking table control device and a shaking table, wherein: (A) a shaking table optimal control which receives a displacement sensor signal of the shaking table system and acts as a higher-order phase lead compensator; The apparatus is arranged in front of an analog shaking table controller, and (B) the shaking table optimal controller controls a signal from a displacement target value input terminal and a displacement of the shaking table body via a first subtractor. A feedback signal from the sensor is input and output to a changeover switch. (C) The changeover switch receives a signal from a shaking table optimal control device or a target displacement value input terminal by a switching operation and performs a second subtraction. (D) the analog type shaking table control device inputs a signal from the changeover switch via a second subtractor and a feedback signal from a displacement sensor of the shaking table body. (E) When oscillation occurs in the shaking table optimal control device, the signal from the displacement target value input terminal is subtracted by the second switching operation of the changeover switch. A shaking table control device characterized by outputting to a shaking table control device of an analog type via a vessel.