Patent Grant
11146191
This application is a 371 of international application of PCT application serial no. PCT/JP2018/002907, filed on Jan. 30, 2018, which claims the priority benefit of Japanese Patent application serial no. 2017-045406, filed on Mar. 9, 2017. The entirety of each of the abovementioned patent applications is hereby incorporated by reference herein and made a part of this specification.
The present invention relates to a technique of simulating a control system, the control system having a control object including a motor and a motor control device controlling the motor.
In a servo mechanism, generally, in order to properly control a motor for driving a load device, control parameters (position gain, speed gain, filter cutoff frequency, etc.) of a servo driver controlling the motor are adjusted. An adjustment method of such control parameters can be exemplified by a method performed by actually driving the motor or the load device. In the adjustment method, a control parameter is set for a motor control device such as the servo driver or the like, a response of the load device according to the control parameter is measured, and suitability of the control parameter is determined.
In addition, instead of adjusting the parameter while driving the actual load device as mentioned above, the adjustment method can be exemplified by a method of determining a control parameter based on a simulation result relating to the response of the load device. For example, as shown in Patent Document 1, physical models of a servo driver and a load device are used, a control parameter is set and a simulation is repeatedly performed. Then, the control parameter to be finally set is determined based on a response result obtained as the simulation result.
Patent Document 1: Japanese Laid-open No. 2009-122779
Patent Document 2: Japanese Laid-open No. 2006-340480
In determining a control parameter for driving a motor in a motor control device, in the case of actually driving a control object including a motor or a load device or the like and measuring its response as conventionally, the driving of the motor and the measurement of the response must be executed every time the control parameter is to be set, and it will take time to determine the control parameter. Further, in the case where the control parameter set at the time of adjustment is improper due to the driving of the actual control object, there is also a risk that the control object may perform an unexpected operation and be damaged.
On the other hand, even if a physical model is used to perform simulation as conventionally at the time of adjusting the control parameter, since the result of the simulation is constrained by the shape or order of the physical model, when there is a difference in the shape of the assumed physical model and characteristics of the actual control object, simulation accuracy may be reduced. In other words, in order to improve the simulation accuracy, it is necessary to reconcile the physical model with the characteristics of the actual control object, and an excessive burden with respect to the adjustment of the control parameter will be placed on a user.
The present invention has been made in view of such problems, and aims to provide a technique for improving the accuracy of simulation of a control system, the control system having a control object including a motor and a motor control device controlling the motor.
In the present invention, in order to solve the above-mentioned problems, a part of a simulation operation is configured to include processing that utilizes impulse response information relating to a predetermined device-side configuration including a control object to calculate a time response of the predetermined device-side configuration. According to such a configuration, it is possible to realize highly accurate simulation according to characteristics of the actual control object.
In details, the present invention is a simulation device simulating a control system, the control system having a control object including a motor and a motor control device controlling the motor, wherein the simulation device includes: a simulation system, including a predetermined feedback system having, as a forward element, at least a predetermined control block structure corresponding to a predetermined device-side configuration including the control object; a holding unit, holding impulse response information for calculation which is information on an impulse response relating to the predetermined device-side configuration; a first response calculation unit, calculating a time response of the predetermined device-side configuration to a predetermined input value by convolution processing using the impulse response information for calculation and the predetermined input value; and a second response calculation unit, calculating a response of the simulation system to a command value input to the simulation system by using the time response of the predetermined device-side configuration calculated by the first response calculation unit.
The simulation device of the present invention includes the simulation system including the predetermined feedback system using at least the control block structure corresponding to the predetermined device-side configuration as the forward element, wherein calculation processing by a first response calculation unit and a second response calculation unit is performed on the premise of the simulation system. With respect to the predetermined device-side configuration, its impulse response information is held as the impulse response information for calculation by the holding unit. Then, the first response calculation unit calculates the time response to the predetermined input value to the predetermined device-side configuration by the convolution processing using the impulse response information for calculation. By utilizing the impulse response information for calculation in this way, the user no longer needs to construct a physical model corresponding to the predetermined device-side configuration for simulation, and it is possible to suitably reflect the actual characteristics of the predetermined device-side configuration including the control object and to accurately calculate the time response thereof.
Here, the impulse response information for calculation held by the holding unit is limited due to reasons such as the capacity required for the holding and so on. Hence, a steady-state deviation may remain in the time response calculated by the first response calculation unit, and the simulation accuracy may be affected as a result. However, in the simulation device of the present invention, considering a feedback loop included in the simulation system, response calculation processing by the second response calculation unit is performed which uses the time response of the predetermined device-side configuration calculated by the first response calculation unit. For example, the second response calculation unit may, in the predetermined feedback system, calculate the response of the simulation system in accordance with a method of feeding back the time response of the predetermined device-side configuration or a predetermined response result calculated from the time response to an input side of the forward element. Accordingly, the steady-state deviation arising from the impulse response information can be reduced, and simulation accuracy can be improved. In addition, the above-mentioned simulation system can also include other control block structures corresponding to nonlinear compensation or feed forward compensation and so on.
Here, a specific configuration of the simulation system in the above-mentioned simulation device is exemplified below. First of all, the impulse response may be the impulse response to a current command, and the predetermined feedback system may be a speed feedback system, and may be configured to include, as the forward element in the predetermined feedback system, the predetermined control block structure and a speed control block structure relating to speed compensation. In this case, the second response calculation unit calculates the time response of the simulation system so that a speed response calculated by the first response calculation unit is fed back to the speed control block structure in accordance with the feedback method. Alternatively, the impulse response may be the impulse response to a speed command, and the predetermined feedback system may be a position feedback system, and may be configured to include, as the forward element in the predetermined feedback system, the predetermined control block structure and a position control block structure relating to position compensation. In this case, the second response calculation unit calculates the time response of the simulation system so that a position response based on the speed response calculated by the first response calculation unit is fed back to the position control block structure in accordance with the feedback method. That is, the simulation device of the present invention can be suitably applied to the simulation system including the predetermined feedback system using the predetermined control block structure corresponding to a device-side impulse response as the forward element, wherein the simulation system may include a control block structure or a feedback system other than the predetermined control block structure and the predetermined feedback system, and a feed forward system.
Here, in the simulation device so far described, the holding unit may hold a plurality of patterns of impulse response information as the impulse response information for calculation; then, based on a driving state of the control object, the first response calculation unit may select predetermined impulse response information from among the plurality of patterns of impulse response information owned by the holding unit, and execute the convolution processing using the selected predetermined impulse response information and the predetermined input value. Since the predetermined device-side configuration includes the control object, the impulse response relating to the predetermined device-side configuration may vary as the driving state of the control object changes. For example, in the cases where the control object is in a first driving state and where it is in a second driving state, since mechanical load or mechanical rigidity or the like of the control object varies, the impulse response relating to the predetermined device-side configuration including the control object will vary. Therefore, by selecting the impulse response (predetermined impulse response) according to the driving state of the control object as mentioned above and subjecting it to the convolution processing by the first response calculation unit, it is possible to realize a suitable simulation according to the driving state of the control object.
In more detail, the plurality of patterns of impulse response information are respectively associated with a plurality of reference driving states which are different driving states of the control object; moreover, the first response calculation unit may select the predetermined impulse response information based on a correlation between the driving state of the control object and each of the plurality of reference driving states. That is, even if the current driving state of the control object is different from the reference driving state corresponding to the held impulse response information for calculation, by selecting the impulse response information associated with any reference driving state based on a correlation between the current driving state and a proximity degree of the reference driving state, the simulation accuracy can be reasonably improved.
In addition, although in the above-mentioned simulation device, the selection of the predetermined impulse response is performed using the correlation between the driving state of the control object and the reference driving state, as one aspect thereof, a case is mentioned where the control object includes a driving object machine driven by a plurality of motors. In such a case, a state amount of the driving object machine, for example, a state amount of a predetermined portion of the driving object machine, is not necessarily uniquely associated with a state amount of the motors. That is, even if the state amount differs between each motor, there are cases where the state amount of the predetermined portion of the driving object machine may be the same. In such a case, instead of associating the state amount of the motors as the reference driving state with the impulse response information, it is preferable to associate the state amount of the predetermined portion of the driving object machine as the reference driving state with the impulse response information. In detail, in the above-mentioned simulation device, in the case where the control object includes the driving object machine driven by a plurality of the motors, the plurality of patterns of impulse response information are respectively associated with the plurality of reference driving states relating to the state amount of the predetermined portion of the driving object machine; then, the first response calculation unit may select the predetermined impulse response information based on a correlation between the state amount of the predetermined portion of the driving object machine and each of the plurality of reference driving states. According to such a configuration, even if the driving object machine is driven and controlled by a plurality of motors, it is possible to easily select a suitable predetermined impulse response by simulation. The state amount of the predetermined portion of the driving object machine can be exemplified by a parameter such as position or temperature or the like of the portion.
Here, in the simulation device so far described, the holding unit may hold the plurality of patterns of impulse response information as the impulse response information for calculation, and in that case, the first response calculation unit may select at least two pieces of impulse response information from among the plurality of patterns of impulse response information owned by the holding unit based on the driving state of the control object, synthesize new impulse response information according to the driving state of the control object from the selected at least two pieces of impulse response information, and execute the convolution processing by using the synthesized new impulse response information and the predetermined input value. By synthesizing the new impulse response information and subjecting it to the convolution processing in this way, even in a driving state that had no corresponding impulse response information, a suitable simulation result can be obtained.
Here, in the simulation device so far described, the holding unit may hold, as the impulse response information for calculation, the plurality of patterns of impulse response information associated with the plurality of reference driving states which are different driving states of the control object, and hold frequency characteristic information associated with each of the plurality of patterns of impulse response information and the plurality of pieces of reference driving information and capable of generating the various impulse response information. In that case, the simulation device may further include an impulse response information generation unit which, based on a correlation between the driving state of the control object and each of at least two of the plurality of reference driving states, generates, from the frequency characteristic information associated with the at least two reference driving states, new frequency characteristic information corresponding to the driving state of the control object, and, based on the generated new frequency characteristic information, generates new impulse response information corresponding to the driving state of the control object. Then, the first response calculation unit may execute the convolution processing by using the new impulse response information generated by the impulse response information generation unit and the predetermined input value.
According to such a configuration, in the simulation device, even if the driving state of the control object is different from the existing reference driving state associated with the impulse response information held by the holding unit, it is possible to generate a frequency characteristic according to the driving state from the frequency characteristic information corresponding to the existing reference driving state, and based on that, generate the impulse response information according to the driving state. Accordingly, even if the impulse response information is not prepared comprehensively with respect to the predetermined device-side configuration as the impulse response information for calculation, it is possible to obtain a suitable simulation result, and the user's burden relating to preparation for simulation can be reduced.
In addition, with respect to the generation of the new frequency characteristic by the impulse response information generation unit, the generation may be performed by weighted averaging the frequency characteristic information corresponding to the existing reference driving state. That is, in the above-mentioned simulation device, the impulse response information generation unit may, based on the correlation between the driving state of the control object and each of the at least two reference driving states, generate the new frequency characteristic information by weighted averaging the frequency characteristic information associated with the at least two reference driving states. Moreover, the weighted averaging is only one aspect for generating the new frequency characteristic information, and other processing may also be performed to generate the new frequency characteristic information.
Here, in the simulation device so far described, there may be further included the impulse response information generation unit selecting at least two pieces of impulse response information from among the plurality of patterns of impulse response information owned by the holding unit and generating the new impulse response information from the selected at least two pieces of impulse response information; in that case, the holding unit may hold the new impulse response information generated by the impulse response information generation unit. According to such a configuration, in generating the new impulse response information, information (for example, frequency characteristic information, etc.) as a basis for the generation is not required. As a result, it is possible to obtain a suitable simulation result while suppressing the user's burden relating to preparation for simulation. In addition, with respect to the generation of the new impulse response information, the impulse response information generation unit may perform the generation by weighted averaging the at least two pieces of impulse response information.
In addition, the present invention may be obtained from an aspect of a simulation method simulating a control system, the control system having a control object including a motor and a motor control device controlling the motor. In this case, the method includes: a step of calculating a time response of a predetermined device-side configuration including the control object to a predetermined input value, by convolution processing using impulse response information for calculation which is information on an impulse response relating to the predetermined device-side configuration and the predetermined input value; and a step of, based on a simulation system including a predetermined feedback system having as a forward element at least a predetermined control block structure corresponding to the predetermined device-side configuration, calculating a response of the simulation system to a command value input to the simulation system by using the time response of the predetermined device-side configuration calculated in the calculation step by the convolution processing. Moreover, it is possible to apply a technical idea disclosed in relation to the invention of the above-mentioned simulation device to the invention of the simulation method, as long as there is no technical inconsistency.
In addition, the present invention can also be grasped from an aspect of a simulation program which causes a simulation device to execute processing including the following steps, wherein the simulation device simulates a control system, and the control system has a control object including a motor and a motor control device controlling the motor. The simulation program causes the simulation device to execute: a step of calculating a time response of a predetermined device-side configuration including the control object to a predetermined input value, by convolution processing using impulse response information for calculation which is information on an impulse response relating to the predetermined device-side configuration and the predetermined input value; and a step of, based on a simulation system including a predetermined feedback system having as a forward element at least a predetermined control block structure corresponding to the predetermined device-side configuration, calculating a response of the simulation system to a command value input to the simulation system by using the time response of the predetermined device-side configuration calculated in the calculation step by the convolution processing. Moreover, it is possible to apply a technical idea disclosed in relation to the invention of the above-mentioned simulation device to the invention of the simulation program, as long as there is no technical inconsistency.
The simulation accuracy of the control system having the control object including the motor and the motor control device controlling the motor is improved.
The servo driver 4 receives a motion command signal relating to the motion of the motor 2 from the standard PLC 5 via the network 1, and receives a feedback signal output from the encoder connected to the motor 2. Based on the motion command signal from the standard PLC 5 and the feedback signal from the encoder, the servo driver 4 calculates a servo control relating to driving of the motor 2, that is, a command value relating to the motion of the motor 2, and supplies a driving current to the motor 2 so that the motion of the motor 2 follows the command value. As the supplied current, AC power sent from an AC power supply 7 to the servo driver 4 is utilized. In the present embodiment, the servo driver 4 is of a type that receives three-phase alternating current, but may also be of a type that receives single-phase alternating current. Moreover, the servo control by the servo driver 4 is feedback control utilizing a position controller 41, a speed controller 42 and a current controller 43 included in the servo driver 4, and the details thereof are described later based on
Here, as shown in
Next, the speed controller 42 performs, for example, proportional integral control (PI control). Specifically, by multiplying an integral amount of a speed deviation which is a deviation between the speed command calculated by the position controller 41 and a detected speed by speed integral gain Kvi, and multiplying a sum of the calculation result and the speed deviation by speed proportional gain Kvp, a torque command is calculated. The speed controller 42 has the speed integral gain Kvi and the speed proportional gain Kvp as control parameters in advance. In addition, the speed controller 42 may perform P control instead of PI control. In this case, the speed controller 42 has the speed proportional gain Kvp as a control parameter in advance. Next, the current controller 43 outputs a current command based on the torque command calculated by the speed controller 42, whereby the motor 2 is driven and controlled. The current controller 43 includes a filter (first order low-pass filter) or one or more notch filters relating to the torque command, and has, as control parameters, cut-off frequencies or the like relating to the performance of these filters.
The control structure of the servo driver 4 includes a speed feedback system using the speed controller 42, the current controller 43 and the control object 6 as forward elements, and further includes a position feedback system using the speed feedback system and the position controller 41 as forward elements. By the control structure configured in this way, it is possible for the servo driver 4 to servo-control the motor 2 so as to follow the position command supplied from the standard PLC 5.
Here, referring back to
Moreover, the processing device 10 has a function of simulating a response of a control object by the servo driver 4 by the adjustment software. By this simulation function, the processing device 10 is capable of calculating the response of the control object when a predetermined control parameter is set in the servo driver 4. Then, based on a simulation result by the processing device 10, a user can determine the control parameter to be set in the servo driver 4, and the determined control parameter will be transmitted from the processing device 10 to the servo driver 4 and be held in the position controller 41, the speed controller 42 and the current controller 43 included in the servo driver 4.
In the present embodiment, as mentioned above, a simulation is executed by the processing device 10 in order to determine the control parameter to be set by the servo driver 4 to drive and control the control object 6. However, instead of this aspect, the simulation may also be performed simply in order to grasp a response to the driving and control of the control object 6 by the servo driver 4. In this case, there is no need for the processing device 10 to be electrically connected to the servo driver 4.
Next, a configuration of the processing device 10 is explained based on
The simulation unit 13 is a functional unit calculating a response of the control object 6 when the control object 6 is servo-controlled by the servo driver 4. The simulation result which is a calculation result by the simulation unit 13 is displayed on the above-mentioned display unit 12. The simulation unit 13 has a simulation system 130, a holding unit 131, and a calculation unit 134.
First of all, the simulation system 130 is explained based on
The basic structure shown in the part (a) in the upper part of
Here, a control structure shown in the part (b) of
In the case where the simulation system 130 has the control structure shown in the part (b) of
Next, a control structure shown in the part (c) of
In the case where the simulation system 130 has the control structure shown in the part (c) of
In this way, the simulation system 130 has an impulse response model unit as a control block corresponding to a mechanical configuration including at least the control object 6 which is to be simulated, and has a feedback system using at least the impulse response model unit as a forward element. In addition, the holding unit 131 is a functional unit holding the impulse response information included in the impulse response model unit included in the simulation system 130. In addition, the calculation unit 134 is a functional unit receiving the impulse response information held by the holding unit 131, and performing simulation processing in accordance with the simulation system 130, that is, calculation of the response speed vsim and the response position psim which are response results of the simulation system 130. The calculation unit 134 has the first response calculation unit 134A and the second response calculation unit 134B as sub functional units. The first response calculation unit 134A is a sub functional unit calculating the response speed vsim relating to the convolution processing utilizing the impulse response information owned by the speed system impulse response model unit 520 of the part (b) of
Here, a flow of calculation processing by the calculation unit 134 for calculating the time response psim of the position and the time response vsim of the speed when a predetermined position command for simulation processing is input to a simulation system is schematically shown in: (1) a case where the simulation system 130 is the control structure shown in the part (b) of
(1) Case where the Simulation System 130 is the Control Structure Shown in the Part (b) of
The flow of the calculation processing in this case is explained in accordance with a flowchart shown in
Next, in S104 to S106, the speed command vcmd is used as an input to the speed system impulse response model unit 520, and convolution processing for calculating the response speed vsim which is an output from the speed system impulse response model unit 520 is performed. Specifically, in S104, an operation in accordance with the following Equation 1 is performed; next, in S105, the parameter n is incremented.
vsim[m+n]=vsim[m+n]+vcmd·gimp[n] (Equation 1)
However, gimp[n] is the impulse response information owned by the speed system impulse response model unit 520. This information means a speed response to an impulse-like speed input.
Then, in S106, it is determined whether or not the parameter n has reached an upper limit, that is, whether or not an upper limit repetition number for repeating the operation by Equation 1 according to length of the impulse response information gimp has been reached. If a negative determination is made in S106, the processing in and after S104 is repeated; if a positive determination is made, the processing proceeds to S107.
Then, in S107, the parameter n is initialized again. Next, in S108, an operation in accordance with the following Equation 2 is performed.
psim[m]=psim[m−1]+vsim[m]·Δt (Equation 2)
That is, in S108, the response speed vsim calculated by the convolution processing is integrated, and the response position psim is calculated. After that, in S109, the parameter m is incremented. Then, in S110, it is determined whether or not the parameter m has reached an upper limit, that is, whether or not an upper limit repetition number for repeating the processing from S102 to S109 according to time (desired response time) for which simulation is intended to be performed by the calculation processing has been reached. If a negative determination is made in S110, the processing in and after S102 is repeated; if a positive determination is made, the present calculation processing is ended.
(2) Case where the Simulation System 130 is the Control Structure Shown in the Part (c) of
The flow of the calculation processing in this case is explained in accordance with a flowchart shown in
Next, in S204, a speed deviation verr which is the deviation between the speed command vcmd and the response speed vsim is calculated. Further, in S205, the speed deviation verr is integrated and an integral amount σ is calculated; in S206, the torque command Tcmd is calculated in accordance with the following Equation 3.
Tcmd=Kvp·(verr+σ·Kvi) (Equation 3)
However, Kvp represents the speed proportional gain, and Kvi represents the speed integral gain. Accordingly, in the present calculation processing, PI control is executed.
Next, in S207 to S209, the torque command Tcmd is used as an input to the current system impulse response model unit 530, and convolution processing for calculating the response speed vsim which is an output from the current system impulse response model unit 530 is performed. Specifically, in S207, an operation in accordance with the following Equation 4 is performed; next, in S208, the parameter n is incremented.
vsim[m+n]=vsim[m+n]+τcmd·gimp′[n] (Equation 4)
However, gimp′[n] is the impulse response information owned by the current system impulse response model unit 530. This information means a speed response to an impulse-like torque input.
Then, in S209, it is determined whether or not the parameter n has reached an upper limit, that is, whether or not an upper limit repetition number for repeating the operation by Equation 4 according to length of the impulse response information gimp′ has been reached. If a negative determination is made in S209, the processing in and after S207 is repeated; if a positive determination is made, the processing proceeds to S210.
Then, in S210, the parameter n is initialized again. Next, in S211, an operation in accordance with the following Equation 5 is performed.
psim[m]=psim[m−1]+vsim[m]·Δt (Equation 5)
That is, in S211, the response speed vsim calculated by the convolution processing is integrated, and the response position psim is calculated. After that, in S212, the parameter m is incremented. Then, in S213, it is determined whether or not the parameter m has reached an upper limit, that is, whether or not an upper limit repetition number for repeating the processing from S202 to S212 according to time (desired response time) for which simulation is intended to be performed by the calculation processing has been reached. If a negative determination is made in S213, the processing in and after S202 is repeated; if a positive determination is made, the present calculation processing is ended.
Here,
In general, a time axis of the impulse response information owned by the impulse response model unit is limited information. Hence, as a result, in the case of using the conventional impulse response model, a response result cannot completely follow the position command, and a steady-state deviation remains, resulting in a decrease in simulation accuracy. In order to reduce the steady-state deviation, the time axis in the impulse response information should be as long as possible; however, in that case, since capacity of the impulse response information may increase, and calculation time for simulation may increase, it is not practical.
On the other hand, according to the calculation processing shown in
In addition, according to the calculation processing shown in
Next, the third calculation processing to be executed by the processing device 10 is explained based on a flowchart shown in
Then, in S302 after S301, based on the driving state of the control object 6, the impulse response information used in the convolution processing performed in S107 to S109, that is, the impulse response information gimp for the speed system impulse response model unit 520 is selected or synthesized. This selection of the impulse response information gimp means to select the impulse response information to be used for convolution processing from among a plurality of pieces of impulse response information owned by the holding unit 131. In addition, the synthesis of the impulse response information gimp means to utilize the plurality of pieces of impulse response information owned by the holding unit 131 to generate new impulse response information to be used for convolution processing. Accordingly, the selected or synthesized impulse response information will be used as the impulse response information gimp for the speed system impulse response model unit 520 in S104 subsequent to S302. The processing in S301 and S302 is performed by the first response calculation unit 134A.
Moreover, in S104 to S106, the convolution processing is performed; after that, when the processing in and after S102 is performed again after a negative determination is made in S110, the impulse response information gimp to be used in the next convolution processing is selected or synthesized again based on the driving state of the control object 6 at that time. Accordingly, in the calculation processing shown in
Hereinafter, examples of selecting or synthesizing the impulse response information gimp based on the driving state of the control object 6 are explained.
In Example 2-1, the load device 3 is set as a conveyance device having a table configured to reciprocate via a ball screw and conveying a predetermined load in one direction. The load device 3 conveys the predetermined load in one direction by the motor 2 rotating positively, and the load device 3 moves in a reverse direction in a state without the predetermined load by the motor 2 rotating negatively. In this case, load inertia is different between when the motor 2 is rotating positively and when the motor 2 is rotating negatively.
Therefore, the holding unit 131 holds in advance impulse response information gimp1 at the time when a conveyance device loaded with the predetermined load is used as the load device 3, and impulse response information gimp2 at the time when a conveyance device without being loaded with the predetermined load is used as the load device 3. Then, the rotational direction (positive rotation or negative rotation) of the motor 2 is set as the driving state of the control object 6. Moreover, in the calculation processing shown in
According to the above, the time response of the simulation system 130 is calculated using the impulse response information that suitably reflects the driving state of the actual control object 6. As a result, accuracy of calculation of the time response of the simulation system 130 is improved.
In Example 2-2, as in Example 2-1, the load device 3 is set as a conveyance device having a table configured to reciprocate via a ball screw. Since the ball screw is relatively long, according to the position of the table to which a nut of the ball screw is attached, mechanical frequency characteristics of the load device 3 vary greatly. Therefore, in order to obtain a highly accurate simulation result, the holding unit 131 has a plurality of pieces of impulse response information gimp of the control object 6 according to the table position at the ball screw, and, with the table position as the driving state of the control object 6, the impulse response information gimp suitable for the driving state is selected.
Specifically, a movable range of the load device 3 at the ball screw from a starting point to an end point is divided into two sections R1 and R2. The holding unit 131 holds two pieces of impulse response information gimp1 and gimp2 respectively corresponding to each section, and the table position calculated from the position of the motor 2 is taken as the driving state of the control object 6. Moreover, in the calculation processing shown in
According to the above, the time response of the simulation system 130 is calculated using the impulse response information that suitably reflects the driving state of the actual control object 6. As a result, accuracy of calculation of the time response of the simulation system 130 is improved.
In Example 2-3, as shown in
Moreover, in the calculation processing shown in
In addition, with respect to the selection of the impulse response information in the case where the table position is between the points X1 and X2, the distances ΔX1 and ΔX2 between the table position and the points X1 and X2 respectively may be evaluated in accordance with another evaluation method, and either of the impulse response information gimp1 and the impulse response information gimp2 may be selected based on the evaluation result.
According to the above, the time response of the simulation system 130 is calculated using the impulse response information that suitably reflects the driving state of the actual control object 6. As a result, accuracy of calculation of the time response of the simulation system 130 is improved.
In Example 2-4, as shown in
Therefore, in the present embodiment, concerning the switching of the impulse response information, the selection of the plurality of pieces of impulse response information held by the holding unit 131 and the switching of the impulse response information for convolution processing are performed with the tip position Pf of the manipulator device, instead of the rotation angles θ1 and θ2, as the driving state of the control object 6. Specifically, first of all, the plurality of pieces of impulse response information held by the holding unit 131 are held in a state associated with the tip position Pf of the manipulator device. Then, in the calculation processing shown in
According to the above, regarding the control object 6 including the load device 3 having redundant degrees of freedom, such as a manipulator device, the time response of the simulation system 130 is also calculated using the impulse response information that suitably reflects the driving state of the actual control object 6. As a result, accuracy of calculation of the time response of the simulation system 130 is improved.
In the embodiments so far described, the impulse response information used in the convolution processing of the calculation processing shown in
For example, taking the conveyance device shown in the above-mentioned Example 2-3 as an example, if the table position is between the points X1 and X2, new impulse response information is synthesized based on the distances ΔX1 and ΔX2 between the table position and the points X1 and X2 respectively. Specifically, based on a ratio between the distance ΔX1 between the table and the point X1 and the distance ΔX2 between the table and the point X2, a new impulse response Newgimp is calculated in accordance with the following Equation 6 (the processing in S302 in
Newgimp=ΔX1/(ΔX1+ΔX2)·gimp1+ΔX2/(ΔX1+ΔX2)·gimp2 (Equation 6)
Then, the new impulse response Newgimp calculated in accordance with Equation 6 will be used in the subsequent convolution processing in S104 to S106 in
According to the above, the time response of the simulation system 130 is more stably calculated using the impulse response information that suitably reflects the driving state of the actual control object 6. As a result, accuracy of calculation of the time response of the simulation system 130 is improved.
Here,
Next, a second functional block diagram relating to the processing device 10 is shown in
In the following, generation processing of new impulse response information by the impulse response generation unit 132 is explained according to a plurality of Examples.
A first example of the generation processing is explained based on
The generation processing shown in
First of all, in S401, the impulse response generation unit 132 extracts frequency characteristic information from the information held by the holding unit 131. As mentioned so far, the holding unit 131 holds a plurality of pieces of impulse response information. In the present embodiment, the holding unit 131 also holds, together with the plurality of pieces of impulse response information, the frequency characteristic information relating to the frequency transfer function, which is basic information for generating each piece of impulse response information via the inverse Fourier transform. In the holding operation, the relevance between impulse response information and the corresponding frequency characteristic information is maintained. In the present embodiment, if it is assumed that four pieces of impulse response information are held in the holding unit 131, the frequency characteristic information corresponding to the four pieces of impulse response information is extracted in S401. When the processing in S401 ends, the processing proceeds to S402.
In S402, a ratio of a norm (distance) between a generation object driving state input as a generation condition and the driving state of the control object 6 corresponding to each piece of the impulse response information currently held in the holding unit 131 is calculated. The calculation of the ratio of the norm is explained based on
In S403, new frequency characteristic information corresponding to the generation object driving state (in the example shown in
NewFw=Σ(RNorm·Fw) (Equation 7)
However, NewFw is the new frequency characteristic information; RNorm represents the ratio of each norm in percentage; and Fw is the frequency characteristic information corresponding to each norm and is extracted from the holding unit 131 by the processing in S401. That is, Equation 7 is an equation calculating new frequency characteristic information by weighted averaging existing frequency characteristic information based on a ratio of a norm.
In the above-mentioned example, when the respective frequency characteristics of the points (3, 3), (6, 3), (3, 6) and (6, 6) are set as Fw1, Fw2, Fw3 and Fw4, respectively, the new frequency characteristic NewFw corresponding to the new point (5, 5) is calculated as follows.
NewFw=0.16Fw1+0.26Fw2+0.26Fw3+0.32Fw4
Next, in S404, by subjecting the new frequency characteristic calculated in S403 to an inverse Fourier transform, the new impulse response information corresponding to the generation object driving state (in the example shown in
Here, in
Then, a speed response of each model is calculated by calculation processing and is shown in
A second example of the generation processing is explained based on
First of all, in S501, the impulse response generation unit 132 extracts a plurality of pieces of impulse response information from the information held by the holding unit 131, as in S401 mentioned above. After that, in S502, by subjecting the plurality of pieces of impulse response information extracted in S501 to weighted averaging based on the generation object driving state, new impulse response information is generated. For example, with respect to the two pieces of impulse response information corresponding to the model 1 and the model 2 shown in Example 3-1 mentioned above, a ratio for weighted averaging is determined based on the load inertia of the new model, and the ratio is utilized to generate the impulse response information for the new model. The ratio for weighted averaging can be determined by properly evaluating a correlation between the load inertia of the model 1 and the model 2 and the load inertia of the new model.
Then, in S503, the newly generated impulse response information is held in the holding unit 131. Accordingly, the calculation unit 134 can use the new impulse response information for the convolution processing in the calculation processing shown in
| Number | Date | Country | Kind |
|---|---|---|---|
| JP2017-045406 | Mar 2017 | JP | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/JP2018/002907 | 1/30/2018 | WO | 00 |
| Publishing Document | Publishing Date | Country | Kind |
|---|---|---|---|
| WO2018/163663 | 9/13/2018 | WO | A |
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| 20040183494 | Nagaoka | Sep 2004 | A1 |
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| 3220216 | Sep 2017 | EP |
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| Number | Date | Country | |
|---|---|---|---|
| 20200052622 A1 | Feb 2020 | US |
