JP4793444B2 - Test apparatus and drive control method of test apparatus - Google Patents

Description

  The present invention relates to a test apparatus that performs various tests such as a fatigue test and a strength test by loading a specimen using a plurality of actuators.

  In a test device that applies a load to a specimen using a plurality of actuators, the amount of displacement of one actuator (referred to as actuator B) is detected, and the other actuator (referred to as actuator A) is controlled according to the amount of displacement. There is something to do. In such a test apparatus, since the actuator A is controlled following the operation of the actuator B, the reaction time of the actuator A is delayed. Therefore, a test apparatus is known that uses a digital signal processor to immediately calculate a control target value for the actuator A based on the displacement detection signal for the actuator B and eliminate the delay in the reaction time of the actuator A. (See Patent Document 1).

JP-A-11-44623

  In the test apparatus disclosed in Patent Document 1, even if a digital signal processor capable of high-speed computation is used, since the operation of the actuator A is not started unless the actuator B is operated, the reaction time delay is completely eliminated. I can't do it. In order to solve such a problem in the conventional test apparatus, a test apparatus capable of appropriately controlling the operations of a plurality of actuators without delay is required.

A test apparatus according to the present invention includes a plurality of actuators for loading a specimen, a sensor for detecting displacement or load of the specimen, and a first calculation for calculating a difference between a signal output from the sensor and a target signal. A second calculation unit that calculates a difference obtained by subtracting an average value of the displacement amount or load amount of each actuator from the displacement amount or load amount of any one of the actuators, a first calculation unit, and a second calculation unit And a control unit that drives and controls each of the plurality of actuators based on a calculation result by the calculation unit.
In the above test apparatus, the control unit controls the servo valve for controlling the hydraulic pressures of the plurality of actuators, and the servo valve by a PID control method based on the calculation results of the first calculation unit and the second calculation unit. It is preferable that a plurality of actuators are driven according to the hydraulic pressure controlled by the servo valve.
In the above test apparatus, a control part is that based by the difference calculated by the first calculating portion and the second calculation unit to the difference calculated for each actuator, controls the driving of the actuators, respectively Can do.
In this test apparatus, the second calculation unit further adds a predetermined correction coefficient set in advance to the difference obtained by subtracting the average value of the displacement amount or load amount of each actuator from the displacement amount or load amount of any actuator. The calculated correction value is calculated for each actuator, and the control unit calculates each actuator based on a value obtained by subtracting the correction value calculated for each actuator by the second calculation unit from the difference calculated by the first calculation unit. It is preferable to control the drive of each.
The test apparatus drive control method according to the present invention includes a plurality of actuators for loading a specimen and a test apparatus drive for controlling each actuator in a test apparatus having a sensor for detecting displacement or load of the specimen. 1st calculation process which is a control method, and calculates the difference of the signal output from the sensor, and a target signal, and the average value of the displacement amount or load amount of each actuator from the displacement amount or load amount of any actuator And a control step for controlling the driving of each of the plurality of actuators based on the first calculation step and the calculation results obtained by the second calculation step. .

  According to the present invention, operations of a plurality of actuators can be appropriately controlled without delaying each other.

1 is a block diagram of a test apparatus according to an embodiment of the present invention. It is the graph which showed the example of the internal stroke displacement amount of each actuator obtained when the magnitude | size of an external displacement setting signal is changed periodically in the test apparatus of this invention. It is a block diagram of the conventional test apparatus. It is the graph which showed the example of the internal stroke displacement amount of each actuator obtained when the magnitude | size of an external displacement setting signal is changed periodically in the conventional test apparatus. It is a block diagram of the testing apparatus by the modification of this invention. FIG. 6 is a block diagram of a test apparatus having three or more actuators according to another embodiment of the present invention.

Explanation of symbols

1a, 1b, 1c: Actuator 2a, 2b, 2c: Servo valve 3a, 3b, 3c: PID controller 4a, 4b, 4c: Subtractor 5a, 5b, 5c: Subtractor 6a, 6b, 6c: Calculator
7: Displacement meter 8: Specimen

-First embodiment-
FIG. 1 shows a block diagram of an electrohydraulic servo type test apparatus according to an embodiment of the present invention. This test apparatus has a pair of actuators 1a and 1b. In order to control the actuators 1a and 1b, a pair of servo valves 2a and 2b, PID control units 3a and 3b, subtracters 4a and 4b, subtracters, respectively. 5a and 5b, and arithmetic units 6a and 6b are provided. Further, a displacement meter 7 commonly used for controlling the actuators 1a and 1b is provided. By loading the specimen 8 by feedback controlling the actuators 1a and 1b using these components, load tests using various structures are performed. For example, the fatigue test of the seismic isolation rubber is performed by periodically changing the displacement amount of the actuators 1a and 1b using the seismic isolation rubber for the specimen 8.

  The specimen 8 is supported by a support frame (not shown), and loads corresponding to the respective displacement amounts are applied from the actuators 1a and 1b. When the specimen 8 is deformed by applying a load from the actuators 1a and 1b, the displacement meter 7 detects the amount of displacement of the specimen 8 caused by the deformation. The displacement meter 7 outputs the detection result of the displacement amount of the specimen 8 to the subtracters 5a and 5b as an external displacement signal.

  The subtractors 5a and 5b receive the external displacement signal representing the displacement of the specimen 8 from the displacement meter 7 as described above, and set the target value of the displacement of the specimen 8 to the actuators 1a and 1b. An external displacement setting signal for setting is input. Subtractors 5a and 5b calculate the difference between the input external displacement signal and the external displacement setting signal (hereinafter referred to as an external displacement difference), and output the calculation results to subtractors 4a and 4b, respectively.

  Actuators 1a and 1b detect the respective internal stroke displacement amounts and output the detection results to arithmetic units 6a and 6b as internal displacement signals A and B, respectively. The calculators 6a and 6b respectively calculate the average displacement value A or B, that is, the value obtained by subtracting these average values, that is, (A + B) / 2 and multiplying by the correction coefficient k, and the calculation results are sent to the subtractors 4a and 4b. Respectively. At this time, the arithmetic unit 6a calculates a value obtained by subtracting the average value of the internal displacement signals A and B from the internal displacement signal A (hereinafter referred to as internal displacement difference A), and further calculates a correction coefficient for the internal displacement difference A. A value multiplied by k (hereinafter referred to as a correction value for the internal displacement difference A) is calculated. On the other hand, the calculator 6b calculates a value obtained by subtracting the average value of the internal displacement signals A and B from the internal displacement signal B (hereinafter referred to as an internal displacement difference B), and further adds a correction coefficient k to the internal displacement difference B. A multiplied value (hereinafter referred to as a correction value of the internal displacement difference B) is calculated. The correction coefficient k is a correction coefficient determined in accordance with the gain ratio between the external control and the internal control in the actuators 1a and 1b, that is, the ratio of the gain with respect to the external displacement signal and the gain with respect to the internal displacement signal. Yes.

  The subtracters 4a and 4b respectively calculate the difference between the external displacement difference output from the subtracters 5a and 5b and the correction value of the internal displacement difference A or B output from the calculator 6a or 6b, respectively. The calculated difference is output to the PID control units 3a and 3b, respectively. At this time, the subtractor 4a calculates a value (hereinafter referred to as a control value A) obtained by subtracting the correction value of the internal displacement difference A calculated by the calculator 6a from the external displacement difference calculated by the subtractor 5a. Output to the PID controller 3a. On the other hand, the subtractor 4b calculates a value obtained by subtracting the correction value of the internal displacement difference B calculated by the calculator 6b from the external displacement difference calculated by the subtractor 5b (hereinafter referred to as a control value B) to perform PID control. To the unit 3b.

  The PID control units 3a and 3b are configured such that the internal stroke displacement amounts of the actuators 1a and 1b correspond to the control value A or B based on the control value A and the control value B output from the subtracters 4a and 4b, respectively. The drive of the servo valves 2a and 2b is controlled so as to match. At this time, a control method called PID control is used. The servo valves 2a and 2b are driven according to the control of the PID control units 3a and 3b, respectively, and control the hydraulic pressure applied to the actuators 1a and 1b, respectively. Actuators 1a and 1b are hydraulic jacks, and the amount of internal stroke displacement changes according to the hydraulic pressure applied from servo valves 2a and 2b, respectively. In this way, the actuators 1a and 1b are driven, and a load corresponding to the drive amount is applied to the specimen 8.

  By performing the control as described above in the test apparatus of FIG. 1, it is possible to synchronize the operation timings of the actuator 1a and the actuator 1b, and the operation of the other actuator is not started unless one actuator is operated. The state can be avoided. As a result, the operations of the actuators 1a and 1b can be appropriately controlled without delaying each other.

  The graph of FIG. 2 shows an example of the internal stroke displacement amount of the actuators 1a and 1b obtained when the magnitude of the external displacement setting signal is periodically changed in the test apparatus of FIG. In this example, the magnitude of the external displacement setting signal is changed so that the internal stroke displacement amounts of the actuators 1a and 1b change at a frequency of 3 Hz and an amplitude of 5 mm, respectively. It can be seen from the graph of FIG. 2 that the displacement delay of the actuator 1b relative to the actuator 1a is about 0.002 seconds at the maximum.

  Next, the test apparatus of FIG. 1 will be described in comparison with a conventional test apparatus. FIG. 3 is a block diagram of a test apparatus that controls the actuator 1b following the operation of the actuator 1a as an example of a conventional test apparatus.

  The test apparatus of FIG. 3 calculates the difference between the input external displacement setting signal and the external displacement signal output from the displacement meter 7 in the subtractor 5a, and inputs the calculation result to the PID control unit 3a. The actuator 1a is displaced by controlling 2a. Further, the difference between the internal displacement signals A and B output from the actuators 1a and 1b is calculated by the calculator 6, and the calculation result is input to the PID control unit 3b to control the servo valve 2b, whereby the actuator 1b Drive. By controlling the actuator 1b following the operation of the actuator 1a in this way, a load corresponding to the drive amount of each of the actuators 1a and 1b is applied to the specimen 8.

  FIG. 4 shows an example of the internal stroke displacement amounts of the actuators 1a and 1b obtained when the magnitude of the external displacement setting signal is periodically changed in the test apparatus of FIG. Also in this example, the magnitude of the external displacement setting signal is changed so that the internal stroke displacement amount of the actuators 1a and 1b changes at a frequency of 3 Hz and an amplitude of 5 mm, respectively, as in the graph of FIG. According to the graph of FIG. 4, the displacement delay of the actuator 1b relative to the actuator 1a is about 0.006 seconds at the maximum, which is larger than the maximum displacement delay of about 0.002 seconds in the graph of FIG. I understand.

  As described above, the displacement delay of the other actuator relative to one actuator 1 can be reduced in the test apparatus of FIG. Therefore, it is possible to appropriately control the operations of the plurality of actuators without delaying each other.

According to the first embodiment described above, the following operational effects can be achieved.
(1) The difference between the external displacement signal from the displacement meter 7 and the external displacement setting signal that is a signal for setting the target of the displacement amount of the specimen 8 is calculated as an external displacement difference by the subtractors 5a and 5b. To do. Further, the difference between the displacements of the actuators 1a and 1b is calculated as the internal displacement difference by the calculators 6a and 6b. Based on these calculation results, the actuators 1a and 1b are driven and controlled by the subtractors 4a and 4b, the PID control units 3a and 3b, and the servo valves 2a and 2b, respectively. Since it did in this way, operation | movement of a some actuator can be appropriately controlled, without mutually delaying.

(2) Since the actuators 1a and 1b are driven according to the hydraulic pressure controlled by the servo valves 2a and 2b, respectively, an electro-hydraulic servo type test that appropriately controls the operations of a plurality of actuators without delaying each other An apparatus can be realized.

(3) In the arithmetic units 6a and 6b, a difference obtained by subtracting the average value of the displacement amount of each actuator from the displacement amount of either the actuator 1a or 1b is calculated for each actuator, and each actuator is calculated based on the calculated difference. It was decided to drive control each. Specifically, the arithmetic unit 6a subtracts the average value of the internal displacement signal A and the internal displacement signal B indicating the displacement amount of the actuator 1b from the internal displacement signal A indicating the displacement amount of the actuator 1a. The difference A is calculated, and the correction value of the internal displacement difference A is calculated by multiplying the internal displacement difference A by the correction coefficient k. Further, the arithmetic unit 6b subtracts the average value of the internal displacement signal B and the internal displacement signal A representing the displacement amount of the actuator 1a from the internal displacement signal B representing the displacement amount of the actuator 1b to obtain the internal displacement difference B. The correction value of the internal displacement difference B is calculated by calculating and multiplying the internal displacement difference B by the correction coefficient k. Then, a value obtained by subtracting the correction value of the internal displacement difference A from the external displacement difference calculated by the subtractor 5a is calculated by the subtractor 4a. Based on the calculation result, the actuator 1a is moved by the PID control unit 3a and the servo valve 2a. In addition to driving, a value obtained by subtracting the correction value of the internal displacement difference B from the external displacement difference calculated by the subtractor 5b is calculated by the subtractor 4b, and the actuator is operated by the PID control unit 3b and the servo valve 2b based on the calculation result. It was decided to drive 1b. Since it did in this way, while controlling two actuators according to target value, it can control so that a difference does not arise in the displacement of both actuators.

  In the above embodiment, a test apparatus as shown in FIG. 5 can be used instead of the test apparatus shown in FIG. This test apparatus includes a subtracter 9 instead of the arithmetic units 6a and 6b, and the subtracter 9 calculates a difference between the internal displacement signals A and B. The calculated difference is output to the subtracters 4a and 4b. The subtractors 4a and 4b calculate the difference between the external displacement difference output from the subtracters 5a and 5b, respectively, and the difference between the internal displacement signals A and B output from the subtractor 9, respectively, and the PID control unit 3a and 3b is output respectively. Even in this case, when the displacement amount of one of the actuators is large, the drive amount of the other actuator is larger than the drive amount of the actuator, so control is performed so that there is no difference between the displacements of both actuators. it can.

-Second Embodiment-
In the first embodiment, the test apparatus having two actuators has been described. However, a similar control method can be applied to a test apparatus having three or more actuators. FIG. 6 shows a block diagram when applied to a test apparatus having three actuators 1a, 1b and 1c. Note that the distances between the load points at which the actuators 1a, 1b, and 1c load the specimen 8 are all equal. That is, each load point is arranged on the specimen 8 in a regular triangle shape. In this test apparatus, the external displacement setting signal and the external displacement signal from the displacement meter 7 are input to the subtracters 5a, 5b and 5c, respectively, and the external displacement difference is calculated in the subtractors 5a, 5b and 5c, respectively. Input to 4a, 4b and 4c, respectively.

  Internal displacement signals A, B, and C are input from the actuators 1a, 1b, and 1c to the calculators 6a, 6b, and 6c, respectively. The arithmetic units 6a, 6b and 6c in this test apparatus are values obtained by subtracting the average value of the internal displacement signals of the actuators 1a, 1b and 1c from the internal displacement signals of the actuators to which the respective arithmetic units correspond, and further multiplying by the correction coefficient k. Are calculated respectively. That is, the arithmetic unit 6a subtracts an average value obtained by summing the internal displacement signals A, B, and C of the actuators 1a, 1b, and 1c and dividing by 3 from the internal displacement signal A of the corresponding actuator 1a, and corrects it. The value multiplied by the coefficient k is calculated. Similarly, the calculator 6b calculates a value obtained by subtracting the average value from the internal displacement signal B of the corresponding actuator 1b and multiplying by the correction coefficient k. The calculator 6c calculates a value obtained by subtracting the above average value from the internal displacement signal C of the corresponding actuator 1c and multiplying by the correction coefficient k. The calculation results obtained by the calculators 6a, 6b, and 6c are output to the subtracters 4a, 4b, and 4c, respectively.

  Subtractors 4a, 4b and 4c calculate the difference between the external displacement difference output from subtractors 5a, 5b and 5c, respectively, and the calculation results output from calculators 6a, 6b and 6c, respectively. The calculation results are output as control values A, B and C to the PID control units 3a, 3b and 3c, respectively. Based on the control values A, B and C, the servo valves 2a, 2b and 2c are respectively controlled by the PID control units 3a, 3b and 3c, so that the actuators 1a, 1b and 1c are respectively driven, and the driving amount thereof A load corresponding to the above is applied to the specimen 8.

  By performing the control as described above in the test apparatus of FIG. 6, the operation timings of the actuators 1a, 1b and 1c can be synchronized. As a result, even when three actuators are provided, the operations of the actuators 1a, 1b and 1c can be appropriately controlled without delaying each other as in the test apparatus of FIG. It should be noted that the operation of each actuator can also be appropriately controlled without delaying each other by applying similar control to four or more actuators.

According to the second embodiment described above, in addition to the functions and effects described in the second embodiment, the following functions and effects can be further achieved.
(1) In the arithmetic units 6a, 6b and 6c, displacement differences obtained by subtracting the average value of the displacement amounts of the actuators from the internal displacement signals A, B or C representing the displacement amounts of the actuators 1a, 1b or 1c Calculate for each actuator. Then, subtractors 4a, 4b, and subtractors 4a, 4b, and subtractors 4a, 4b, and 6 are obtained by subtracting a correction value obtained by multiplying the displacement differences calculated for each actuator by arithmetic units 6a, 6b, and 6c from the external displacement difference calculated by subtractor 5a The actuators 1a, 1b, and 1c are respectively driven by the PID controllers 3a, 3b, and 3c and the servo valves 2a, 2b, and 2c based on the calculation results. Since it did in this way, while controlling three or more actuators according to a target value, it can control so that a difference does not arise in the displacement of both actuators.

  In each of the above embodiments, the target displacement value of the specimen is set, the displacement of the specimen and the displacement of each actuator are detected, and a plurality of actuators are set based on the displacement target value and the detection result of the displacement. Although the case of displacement control for driving control has been described, the present invention can be similarly applied to the case of load control by replacing the displacement in each of the above embodiments with a load. That is, the load target value of the specimen is set, the load applied to the specimen and the load of each actuator are detected, and a plurality of actuators are driven and controlled based on the load target value and the load detection result be able to.

  Each embodiment and various modifications described above are merely examples, and the present invention is not limited to these contents as long as the features of the invention are not impaired.

  In each of the above embodiments, the first calculation unit is realized by the subtracters 5a, 5b, and 5c, the second calculation unit is realized by the calculators 6a, 6b, and 6c, and the control unit is the subtractors 4a, 4b. 4c, PID control units 3a, 3b and 3b, and servo valves 2a, 2b and 2c. However, this is merely an example, and when interpreting the invention, there is no limitation or restriction on the correspondence between the items described in the above embodiment and the items described in the claims.

Claims (5)

A plurality of actuators for loading the specimen;
A sensor for detecting the displacement or load of the specimen;
A first calculation unit for calculating a difference between a signal output from the sensor and a target signal;
A second calculation unit that calculates, for each actuator, a difference obtained by subtracting the average value of the displacement amount or load amount of each actuator from the displacement amount or load amount of any one of the actuators ;
The first based on the calculation result by the calculating unit and the second calculating unit, the test device characterized by a control unit for driving and controlling the plurality of actuators, respectively. The test apparatus according to claim 1.
Wherein the control unit includes a servo valve for controlling the hydraulic pressure of the plurality of actuators respectively, based on the calculation result of the first calculation unit and the second calculation unit, driving the servo valve by PID control method A PID control unit for controlling,
The plurality of actuators are driven according to the hydraulic pressure controlled by the servo valve. The test apparatus according to claim 1 or 2,
Prior Symbol controller, the first based on the said and the calculated difference second calculation unit to the difference calculated for each actuator by the calculation unit, characterized by drive control of the actuators respectively test apparatus. The test apparatus according to claim 3.
The second calculation unit corrects the difference obtained by subtracting the average value of the displacement amount or the load amount of each actuator from the displacement amount or the load amount of any one of the actuators, and further multiplied by a predetermined correction coefficient. Calculate the value for each actuator,
The control unit controls driving of each actuator based on a value obtained by subtracting a correction value calculated for each actuator by the second calculation unit from the difference calculated by the first calculation unit. Test equipment. A test apparatus drive control method for driving and controlling each actuator in a test apparatus having a plurality of actuators for loading a specimen and a sensor for detecting displacement or load of the specimen ,
A first calculation step of calculating a difference between a signal output from the sensor and a target signal;
A second calculation step of calculating, for each actuator, a difference obtained by subtracting an average value of the displacement amount or load amount of each actuator from the displacement amount or load amount of any one of the actuators;
A drive control method for a test apparatus , comprising: a control step of driving and controlling each of the plurality of actuators based on calculation results of the first calculation step and the second calculation step .

Images