JP4237928B2 - Exciter control device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a vibration exciter control device that vibrates a device under test according to an arbitrary vibration waveform.
[0002]
[Prior art]
In a vibration exciter that vibrates a DUT according to an arbitrary vibration waveform and tests its performance and durability, it is required that distortion of the vibration waveform is suppressed and the target vibration waveform is reproduced correctly. The
[0003]
2. Description of the Related Art Conventionally, a control device for this type of vibration exciter is shown in FIG.
[0004]
This system basically includes a servo actuator 1, a controller 2, a sensor 3, and a signal observer 4.
[0005]
The controller 2 includes a signal generator 2-1 that outputs a target value of the excitation waveform, an adder 2-4, an adjuster 2-2, a calculator 2-3, and an adder 2-5.
[0006]
The sensor 3 includes a displacement sensor 3-1, a speed sensor 3-2, and an acceleration sensor 3-3.
[0007]
The controller 2 compares the target value of the excitation waveform output from the signal generator 2-1 with the displacement detection signal of the displacement sensor 3-1, and adds a gain to the deviation by the adjusting unit 2-2. The multiplied signal is input to the adder 2-5. On the other hand, a signal obtained by multiplying the acceleration detection signal of the acceleration sensor 3-3 by the calculation unit 2-3 is an input to the addition unit 2-5. Then, the adder 2-5 compares both signals and outputs the deviation to the servo actuator 1.
[0008]
In this way, the controller 2 feeds back the acceleration of the servo actuator 1 to the excitation waveform, so that the target excitation waveform is reproduced with high accuracy.
[0009]
[Problems to be solved by the invention]
By the way, when a device under test is attached to a vibration exciter, the controller 2 performs fixed position control for stopping the servo actuator 1 at a predetermined position in response to a command from the operator.
[0010]
However, since the controller 2 has a control algorithm that feeds back acceleration, when the servo actuator 1 is moved by accidentally hitting the device under test against the shaker, disturbance acceleration is transmitted via the acceleration sensor 3-3. There is a possibility that the servo actuator 1 may be vibrated in response to the input of, and there is a problem that the vibration exciter moves without permission.
[0011]
The present invention has been made in view of the above problems, and an object of the present invention is to prevent malfunction of a shaker stopped at a fixed position in a shaker control device that constitutes a feedback loop with an acceleration sensor. To do.
[0012]
[Means for Solving the Problems]
According to a first aspect of the present invention, there is provided a servo actuator for driving a vibration exciter, a signal generating means for generating a target vibration waveform, a displacement feedback means for feeding back a displacement of the servo actuator to the vibration waveform, and an acceleration of the servo actuator. And a control unit for selectively stopping the control by the acceleration feedback means , the control switching means at a fixed position. The control by the acceleration feedback means is stopped during the fixed position control to be stopped .
[0014]
Operation and effect of the invention
According to the first invention, the control switching means stops the control by the acceleration feedback means, so that the servo actuator can be prevented from starting even when disturbance acceleration is input via the acceleration sensor 3-3 . When the control switching means stops the control by the acceleration feedback means at the time of the fixed position control, for example, when the test object is attached to the shaker, the test object is accidentally hit the shaker. However, the operability can be improved without the servo actuator moving freely.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.
[0016]
FIG. 1 is a system block diagram showing a basic configuration of a control device for a servo actuator provided in a vibration testing machine. This system is composed of an electrohydraulic servo actuator 1, a controller 2, a sensor 3, and a signal observer 4 for driving a vibration exciter, as in the conventional system.
[0017]
The controller 2 includes a signal generator (signal generation means) 2-1, an adding unit 2-4, an adjusting unit 2-2, a calculating unit 2-3, an adding unit 2-5, and a control unit that output a target value of the excitation waveform. It comprises a switching unit 2-6.
[0018]
As the displacement feedback means, the displacement sensor 3-1, the adding unit 2-4, and the adjusting unit 2-2 constitute a displacement feedback loop that feeds back the displacement of the servo actuator 1 to the excitation waveform. That is, the adding unit 2-4 compares the displacement detection signal of the displacement sensor 3-1 with the excitation waveform signal output from the signal generator 2-1, and applies a gain to the deviation by the adjusting unit 2-2. And the displacement of the servo actuator 1 is fed back to the excitation waveform.
[0019]
As an acceleration feedback means, an acceleration feedback loop for feeding back the acceleration of the servo actuator 1 to the excitation waveform is configured by the acceleration sensor 3-3, the calculation unit 2-3, and the addition unit 2-5. In other words, the addition unit 2-5 receives the signal gained by the adjustment unit 2-2 and adds the signal gained by the calculation unit 2-3 to the acceleration detection signal of the acceleration sensor 3-3. The difference between both signals is output to the servo actuator 1 from the adder 2-5. As a result, the acceleration of the servo actuator 1 is fed back to the excitation waveform, and the target excitation waveform is reproduced with high accuracy.
[0020]
The present invention includes a control switching unit 2-6 that switches an input path to the servo actuator 1 as a control switching unit that can selectively stop acceleration feedback control. The control switching unit 2-6 cuts off the signal from the addition unit 2-5 and the first position at which the signal from the addition unit 2-5 is sent to the servo actuator 1, and directly transmits the signal from the adjustment unit 2-2 to the servo actuator 1. To the second position to send to.
[0021]
The control switching unit 2-6 is switched to the first position when oscillating the shaker, and acceleration feedback is performed. On the other hand, the control switching unit 2-6 is switched to the second position during fixed position control for stopping the shaker at a fixed position. The acceleration feedback is stopped.
[0022]
When configured as described above, for example, when a test object is attached to a vibration exciter, the controller 2 performs fixed position control for stopping the servo actuator 1 at a predetermined position in response to a command from the operator, and a control switching unit. Switch 2-6 to the second position. Thus, since the feedback of the acceleration is stopped during the fixed position control of the controller 2, it is possible to avoid that the servo actuator 1 starts to move even if disturbance acceleration is input via the acceleration sensor 3-3. Therefore, for example, when attaching the device under test to the vibrator, the servo actuator 1 will not move freely even if the device under test is accidentally hit against the vibrator, and this workability can be improved. .
[0023]
The present invention is not limited to the above-described embodiment, and it is obvious that various modifications can be made within the scope of the technical idea.
[Brief description of the drawings]
FIG. 1 is a system block diagram of a vibration exciter control apparatus according to an embodiment of the present invention.
FIG. 2 is a system block diagram of a vibration exciter control device showing a conventional example.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Servo actuator 2 Controller 2-1 Signal generator 2-2 Adjustment part 2-3 Calculation part 2-4 Addition part 2-5 Adjustment part 2-6 Control switching part 3 Sensor 3-1 Displacement sensor 3-2 Acceleration sensor

Claims (1)

Servo actuator for driving the vibrator, signal generating means for generating a target excitation waveform, displacement feedback means for feeding back the displacement of the servo actuator to the excitation waveform, and the acceleration waveform of the servo actuator for excitation And a control switching means for selectively stopping control by the acceleration feedback means , wherein the control switching means stops the vibration exciter at a fixed position. An apparatus for controlling a vibration exciter is characterized in that the control by the acceleration feedback means is stopped during the fixed position control .

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