JP2004220577A - Simulation method and simulation program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a simulation method and program suitable for a linked simulation with control software controlling a mechanism system. <P>SOLUTION: This mechanism simulator simulates behavior of a mechanism along a time axis based on a hybrid model description. This simulator analyses the hybrid model description and extracts a description of a continuity equation, a description on a state transition, and a description on an additional processing respectively. A first program based on the description on the continuity equation, a second program based on the description on the state transition and a third program based on the description on the additional processing which are called in the execution of the simulation respectively are created. The first, second and third programs are connected to the execution part of the mechanism simulator. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

  The present invention relates to a method and a program for simulating the behavior of a machine or the like using a computer, and in particular, the present invention uses a hybrid model.

  Currently, when a computer is used to simulate the behavior of a machine, plant, or the like, a method called hybrid modeling is used. Simulation using a hybrid model is called “hybrid simulation”. A system that performs such a simulation behavior may be called a “hybrid system”.

  Hybrid models created for the purpose of simulation are conceptually a continuous system model expressed by a set of simultaneous equations of ordinary differential equations and algebraic equations, and a state transition model for expressing state transitions caused by events. It is a model that combines According to the hybrid model, a system in which the state represented by the continuous system model is instantaneously switched by an external event or the like can be represented.

  As a language for describing a hybrid model, there is a language called HCC (Hybrid Concurrent Constraint Programming) created at Palo Alto Research Laboratory of Xerox Corporation (trademark) (see Non-Patent Document 1 below). HCC is in the process of being developed and is still being studied at NASA's Ames Institute. HCC is a kind of technique called constraint processing programming (constraint programming), and treats ordinary differential equations and algebraic equations expressing a continuous system model as constraints, and can describe these equations as they are in no particular order. A description for controlling the state transition is added to such a constraint description to complete a hybrid model of the HCC language. According to the HCC, equations can be listed (programmed) as constraints as they are, and a complicated model can be described.

  By using the hybrid model technique, the characteristics of the system can be model-represented by ordinary differential equations or the like, and the behavior of the system can be simulated from the initial state according to the transition of time.

As an application example of a hybrid model technology capable of accurately modeling an object or a phenomenon that can be expressed by a differential equation or the like, there is a mechanism simulation of a mechatronics device whose mechanism is controlled by software. According to such a mechanism simulation, prototyping, testing, debugging, or the like of control software for controlling the mechanism can be performed even in a situation where there is no actual machine of the mechanism.
Internet <URL: http://www2.parc.com/spl/projects/mbc/publications.html#cclanguages>

  However, a known programming language that can handle a hybrid model is not necessarily developed for application to the mechanism simulation of a mechatronic device, and therefore has the following problems.

  For example, HCC of Xerox Corporation (trademark) of the United States is an interpreter-type programming language. For example, when the control software receives an operation command to be transmitted to a mechanism from a mechanism to an actuator as a control signal from outside the simulator, It is necessary to define external functions and the like individually, and it requires considerable contrivance in programming.

  Specifically, the model creator needs, for example, the following work for programming the external function.

(1) A program of an external function is described in another language such as C using an external function description API specific to the HCC language.

(2) The described external function program is compiled by a C language compiler to create, for example, a dynamic link library that can be linked at the time of execution.

(3) The HCC interpreter arranges the created library in a directory whose path can be specified so that the HCC interpreter can call the library.

  Therefore, the model creator needs to learn an API for describing an external function specific to the HCC language, and it takes time to separately compile the external function when executing a simulation.

  Regarding the method of calling the external function in the model description, the HCC that does not manage the execution of the external function by associating it with the event can be described both when it is called at the moment when a state transition occurs and when it is called at the time of numerical integration. Therefore, it is difficult for the model creator to grasp the timing at which the external function is executed, and a high level of skill is required for model creation.

  The present invention has been made in view of such circumstances, and a complex mechanism system can be easily and accurately modeled using a hybrid model, and a simulation suitable for coordination simulation with control software for controlling the mechanism system is also provided. It is intended to provide a method and a program.

  It is another object of the present invention to allow a program describing a process related to external cooperation to be directly included in a part of a hybrid model description, and to expand a simulation application range.

  A simulation method according to one aspect of the present invention is a simulation method for simulating the behavior of a target mechanism along a time axis based on description data using a hybrid model, wherein a continuous system included in the description data is included. An analysis step of analyzing the description data to extract a description of an equation, a description of switching of the continuous system equation in accordance with a state transition, and a description of a process other than the process represented by the continuous system equation; and the analysis step. A first program generation step of generating a first program based on the description of the continuous system equation extracted in step (a), and a description of switching of the continuous system equation accompanying the state transition extracted in the analysis step. A second program generation step for generating a second program. And a third program generation step of generating a third program based on a description of a process other than the process represented by the continuous system equation extracted in the analysis step, and executing the first program. A converting step of converting the continuous system equation into a data structure capable of performing a simulation, and a switching step of executing the second program to switch between valid / invalid of the continuous system equation according to occurrence of an event Using the data structure corresponding to the continuous system equation validated in the switching step, solving the continuous system equation by numerical integration along a time axis, and outputting data representing the behavior of the mechanism. A simulation execution step of executing a simulation, and the third program By executing comprises a processing execution step of executing a processing other than the processing represented by the continuous system equation.

  ADVANTAGE OF THE INVENTION According to this invention, a complex mechanism system can be modeled easily and accurately using a hybrid model, and the simulation method and program suitable also for cooperation simulation with the control software which controls this mechanism system can be provided.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(1st Embodiment)
FIG. 1 is a block diagram showing a schematic configuration of the mechanism simulator according to the first embodiment of the present invention.

  This embodiment includes a hybrid model preprocessing unit 201 and a hybrid model simulation execution unit 102. The hybrid model description 104 is a source program described in a hybrid model description language or the like, and is an input to the hybrid model preprocessing unit 201 according to the present embodiment. The output from the hybrid model simulation execution unit 102 is a calculation result of a variable value obtained as a result of the continuous system simulation by the continuous system simulation unit 103 and its time history. This output is stored in the variable value time history storage unit 105.

  As shown in FIG. 1, the hybrid model preprocessing unit 201 includes a control information analysis unit 110. The hybrid model simulation execution unit 102 includes an event processing unit 111, an equation syntax analysis unit 112, an equation data storage unit 114, a continuous system equation switching unit 115, an additional processing execution unit 205, and a continuous system simulation unit 103. Note that the present embodiment can be configured using a general computer, and its basic hardware configuration includes a central processing unit (CPU), a memory, an external recording device, and a communication interface (I / F, not shown). ) And input devices such as a display device, a keyboard, and a mouse. Further, an operating system (OS) for controlling these hardware is provided. The mechanism simulator according to the embodiment of the present invention can be implemented as application software that operates on such an operating system.

  Before describing the configuration of the mechanism simulator according to the present embodiment and its processing procedure, here, first, how the hybrid model description 104 is described will be described using a specific example.

  FIG. 2 and FIG. 3 are diagrams illustrating a mechanism to be described in a hybrid model according to a specific example. This mechanism is a cylinder device having a simple structure including a valve 301, a spring 303, and a piston 302.

  The valve 301 opens and closes in response to an external command (event). An event that changes the air flow in the cylinder device to the right as shown in FIG. 2 is hereinafter referred to as “Left”, and an event that changes the air flow to the left as shown in FIG. 3 is referred to as “Right”. FIG. 2 shows a state in which a Left event is given to the valve 301, and a rightward force on the paper surface is acting on the piston 302. The equation of motion showing this state is "-F = mx", as shown at the bottom of the cylinder device. On the other hand, FIG. 3 shows a state in which a right event is given to the valve 301, the direction of the air flow changes, and the equation of motion changes to "F = mx" as shown in FIG. I have.

  FIG. 4 illustrates such a behavior of the mechanism as a state transition diagram including state transitions and equations of motion corresponding to each state. The hybrid model refers to a state transition as shown in FIG. 4 and a description of each state expressed by a differential equation, an algebraic equation, or a simultaneous equation (continuous system equation) thereof. FIG. 4 shows that there are two states, and that there is a state transition between the two states.

  In the present invention, based on the state transition diagram of FIG. 4, the specific contents of the hybrid model are described in HCC (Hybrid Concurrent Constraint Programming) language, and processing other than processing expressed by continuous system equations, for example, external processing The hybrid model description 104 is generated by describing a process (hereinafter, referred to as “additional process”) related to cooperation with the program in a predetermined program language.

  FIG. 5 is a diagram showing an example of a program corresponding to the hybrid model description according to the present invention. In FIG. 5, assume that the logical line numbers of the (source) program are L1 to L23. L3, L4, and L8 correspond to the description of the operating conditions such as the initial state of the mechanical device and the valve operation timing, and L5 and L6 correspond to the description of the state transition shown in FIG. In addition, L9 to L23 are descriptions relating to the additional processing, and here, processing having a content of “writing the current state to a file” is described. Note that "C" is designated in the module statement, and the corresponding L9 to L17 are program descriptions in the C language.

  In the HCC language, as can be seen from L5 and L6 in FIG. 5, the equation of motion can be described directly in the program. The state differs between L5 and L6. In each state, a condition for transition to the state is referred to as a precondition, which is described after "always if". A condition for canceling the state, in other words, a condition for transitioning from the state, is referred to as a transition condition, and is described after "watching".

  In the HCC, the program is not executed in the order of program description (for example, the order of logical line numbers L1 to L8 in FIG. 5). The HCC searches and executes individual program descriptions that are established along the time axis for executing the simulation. That is, the order of the logical row numbers L1 → L8 has no relation to the execution order. For example, when the simulation is started, only L3 and L8 are valid. Here, since the event Right (ev1) is generated by L3, Right, which is a precondition of L6, becomes valid, and the equation of motion eq2 described in L6 becomes valid. That is, the simulation is executed from the state on the left side of FIG.

  Further, when the time reaches 50, L4 becomes valid, an event Left (ev2) occurs, the transition condition of L6 (“watching” or less, that is, Left) becomes valid, and the motion equation eq2 of L6 becomes invalid. Instead, the precondition of L5 becomes valid, and the equation of motion eq1 becomes valid.

  Although the above-described program example describes the case where the state is changed by an external event (L5, L6), the state may be changed according to the internal situation. For example, when the valve 301 is not switched in FIG. 2, the moving piston 302 comes into contact with the spring 303 and receives a reaction force from the spring 303. That is, regarding the position of the piston 302, there is a case where a state transition occurs even when there is no external event. In such a case, for example, the necessity of the state transition can be determined based on the evaluation result of an internal variable evaluation expression (inequality) such as whether or not x is positive.

  In general, a hybrid model is a combination of a continuous system model represented by a system of simultaneous ordinary differential equations and algebraic equations, and a state transition model for representing a state transition accompanying an event occurrence. . According to the hybrid model, a system in which the state represented by the continuous system model is instantaneously switched by an external event or the like can be represented.

  Further, when the time reaches 100, L19 becomes valid, an event E (ev5) occurs, and a function called cPrint is called with the value of the argument x (L18 to L23). This description indicates that additional processing for saving the state at that time in a file is executed, and the specific processing contents are described in, for example, the C language in L9 to L17.

  Lines L18 to L23 are the contents of the hybrid model description 104 that controls the additional processing (L11 to L16). The description “process (E) cPrint (x)” is a command syntax for executing additional processing, that is, cPrint (x), when the event E occurs. Here, the event related to the execution control of the additional processing can be described using the same event as the Left event and the Right event related to the switching of the continuous system equation.

  According to this embodiment, (1) the contents of the additional processing can be described on the same program source as the description corresponding to the hybrid model having the switching of the continuous system equation. In addition, (2) control such as calling additional processing can be described in a hybrid manner. Therefore, a simple and easy-to-understand simulation model can be described.

  Next, processing in the hybrid model preprocessing unit 201 will be described. The hybrid model description 104 is first processed by the control information analysis unit 110 of the hybrid model preprocessing unit 201, and a model equation registration program 202, an event control program 203, and a simulation execution additional processing program 204 are generated.

  As software modules constituting the hybrid model simulation execution unit 102, a function for registering a model equation and a function for switching a continuous system equation are provided as API (Application Program Interface) functions. The model equation registration program 202 and the event control program 203 are programs that appropriately combine descriptions for calling the corresponding API functions according to the input hybrid model description 104. From this viewpoint, the hybrid model preprocessing unit 201 is considered as a kind of compiler in which the input is a hybrid model description 104 and the output is a C program (source) including a description of an API function call in C language, for example. You can also. The model equation registration program 202 and the event control program 203 are further compiled by a compiler such as C language, and a library that can be dynamically linked at the time of execution is generated. The hybrid model simulation execution unit 102 links the generated dynamic link library when executing the simulation, and completes and executes a simulation program that faithfully reproduces the input hybrid model. Note that these generated libraries need not necessarily be dynamic link libraries, and may be static libraries.

Various specifications and the like of specific software modules constituting the application interface of the hybrid model simulation execution unit 102 can be considered, but here, for convenience of explanation, it is assumed that the following three API functions are defined at a minimum. The programming language is C language.

  The first API function XXX_AddEqnData specifies a pointer of a character string representing one continuous system equation as an argument. XXX_AddEqnData performs a process of parsing the continuous system equation, converting the description of the continuous system equation into a data structure (internal data expression) capable of executing a simulation, and registering the internal data expression in the equation data storage unit 114. Here, a unique ID number is assigned to the continuous system equation.

  For example, assuming that the expression "ab / cos (a- (c + b))-3c" is given, a tree structure as shown in FIG. 6 is generated as the internal data expression. In this tree structure, for example, reference numeral 61 denotes a parent node (section) of a linear polynomial, 62 denotes a multiplication node, 63 denotes a division node, 64 denotes a node of an external function (meaning other than the four arithmetic operations), and 65 denotes a linear polynomial. It represents the nodes of each of the constituent terms. In this example, all of the leaves corresponding to the tree structure are variables (a, b, c), which are added to real coefficients to form a linear form. The linear form is used as an argument of an external function such as cos, and is subject to multiplication and division. The variable is separately provided with a flag indicating whether or not the value is determined, and the current value of the variable is held based on such tree-structured data. If the values of all the leaves of the tree structure (that is, the values of the variables) are determined, the value of the expression can be calculated. In the equation data storage unit 114, a tree structure is formed in advance by connecting the internal data structures so that the calculation of the value of the equation can be performed at a high speed. If any error occurs in the above processing, an error code is set in err. If the processing is completed normally, the ID number of the registered equation is used as the return value.

  The second API function XXX_ActivateEqn activates the equation corresponding to the ID number of the equation specified in the argument. If an already valid equation is specified, do nothing. The return value is an error code.

  The third API function XXX_DeActivateEqn invalidates the equation corresponding to the ID number of the equation specified in the argument, contrary to XXX_ActivateEqn. Does nothing if an invalid equation is specified.

  The control information analysis unit 110 first generates a function (InitEqnData) that sequentially calls XXX_AddEqnData for necessary equations. This corresponds to the model equation registration program 202 (first program).

  Further, the control information analysis unit 110 also generates a function (ChangeEqn) for checking conditions and changing (exchanging) equations every time the time advances by Δt during the simulation. This corresponds to the event control program 203 (second program).

  Here, the ChangeEqn function detects the occurrence of a Left event, a Right event, and an E event by using the GetEvent function. The ChangeEqn function is called from the event processing unit 111 for each time step during simulation execution.

  In the hybrid model simulation execution unit 102, the event processing unit 111 and the continuous system simulation unit 103 are separated as can be seen from FIG. Therefore, the event control program 203 does not include a time-dependent module such as time integration, and the corresponding event processing unit 111 only switches the valid / invalid flag of the continuous system equation.

  By employing such a simulator configuration, an event related to an interface with an external device and an event related to a hybrid description can be managed by the same process (if (GetEvent (event) process)).

  Also, the hybrid model preprocessing unit 201 can easily generate a hybrid simulation execution program because the hybrid simulation model is output once in the same language as the additional processing.

  As described above, the cooperation between the hybrid simulation and the external device becomes easy.

  Further, the control information analysis unit 110 extracts the content description of the additional processing from the hybrid model description 104. Such a description corresponds to the simulation execution unit addition processing program 204 (third program). The simulation execution unit addition processing program 204 corresponds to a source of a program originally described in the C language or the like in the hybrid model description 104. For example, in the hybrid model description 104 shown in FIG. 5, a module statement is referred to and a portion described in C language is extracted. The extracted simulation execution unit additional processing program 204 is compiled by a C language compiler to generate a dynamically linkable library. The additional processing execution unit 205 plays a role of an interface for calling the dynamically linkable library. Note that the generated library does not necessarily need to be a dynamic link library, but may be a static library. The language for describing the contents of the additional processing is not limited to the C language.

By the processing in the hybrid model preprocessing unit 201 as described above, for example, the following C language source program is automatically generated for the hybrid model description shown in FIG.

  Note that GetEvent is a function for checking whether an event having the name (eventname) specified in the argument has occurred.

  The above program is compiled by the C language compiler as described above, further prepared in the form of a dynamic link library, and linked at the time of execution.

  In the present embodiment, an example in which the C language is used as the program language has been described. However, the present invention is not limited to this. For example, another program language such as a C ++ language or a SpecC language may be used. .

  Next, execution of a simulation will be described. At the time of executing the simulation, the hybrid model simulation execution unit 102 is started, and the simulation is executed by calculating the value of the continuous system equation. At this time, the continuous system equation switching unit 115 is called inside the event processing unit 111, and executes switching of the continuous system equation using a valid / invalid flag. The event processing unit 111 corresponds to the event control program 203 (second program; ChangeEqn) generated in the pre-processing. In the state of FIG. 2, the motion equation eq1 of FIG. 5 is invalid, and the motion equation eq2 is valid. Here, in the situation of FIG. 3 in which the event of Left occurs, the flag is operated so that the motion equation eq1 of FIG. 5 is made valid and the motion equation eq2 is made invalid. These valid / invalid flags are managed as attribute data of each equation stored in the equation data storage unit 114.

  The continuous system simulation unit 103 refers to the equation data storage unit 114, and performs a numerical integration step by step on the internal data representation of the continuous system equation stored in the storage unit 114 in the form of a tree structure. . The simulation is an initial value problem for a nonlinear system of equations consisting of a system of ordinary differential equations and algebraic polynomials. For this reason, for example, the initial state shown in FIG. 2 is given. Specifically, the value of the solution is calculated using, for example, a generally used Runge-Kutta algorithm.

  Necessary data is output from the mechanism simulator, and the process returns to the process of the continuous system equation switching unit 115, and a simulation of a necessary time is executed by repeating the above process. The simulation result is stored in the variable value time history storage unit 105 and is used for analysis after the end of the simulation.

  FIG. 7 is a flowchart illustrating a series of processing procedures in the mechanism simulation according to the first embodiment of the present invention described above. This processing procedure can be broadly divided into a hybrid model preprocessing stage and a simulation execution stage.

  First, the hybrid model description 104 is input to the control information analysis unit 110, and syntax analysis of the hybrid model is performed (step S1). The control information analysis unit 110 generates a model equation registration program 202, an event control program 203, and a simulation execution additional processing program 204 as shown in FIG. After completing the pre-processing for executing the simulation, the process proceeds to the stage of executing the simulation.

  First, the equation syntax analysis unit 112 is called from the hybrid model simulation execution unit 102. The equation syntax analysis unit 112 corresponds to the model equation registration program 202 (first program; InitEqnData), and calls the API function XXX_AddEqnData therein. Thereby, the description data of the continuous system equation is converted into a data structure that can execute the simulation. The converted data is registered in the equation data storage unit 114 (Step S2).

  After the initial state based on the hybrid model description 104 is determined in step S3, it is detected in step S4 whether an event has occurred. Therefore, the hybrid model simulation execution unit 102 calls the event processing unit 111. The event processing unit 111 corresponds to the event control program 203 (second program; ChangeEqn), and calls GetEvent internally. If an event has occurred, control proceeds to step S5. If no event has occurred, the process proceeds to step S6, where the continuous-system simulation unit 103 performs numerical integration.

  In step S5, it is determined whether or not the generated event is related to the additional processing. If the event is not related to the additional processing, it is determined in step S9 whether or not it is necessary to switch the continuous system equation accompanying the state transition. If it is necessary to switch the equation, in step S10, the active continuous equation is switched by operating the valid / invalid flag. Therefore, the API function XXX_ActivateEqn or XXX_DeActivateEqn is called. After the execution of step S9 or step S10, in step S6, the continuous system simulation unit 103 performs numerical integration.

  If the event that has occurred is related to the additional processing, the corresponding additional processing is executed in step S11. As a specific example of the additional processing, processing such as displaying the progress of the processing on a screen or outputting data related to the simulation to a file can be considered. After the additional processing is performed in step S11, the process proceeds to step S6, where the continuous system simulation unit 103 performs numerical integration.

  Next, an end condition is determined in step S7. Here, it is determined whether or not the time has reached a predetermined simulation end time. When the simulation end time is reached, the simulation execution ends. Until then, the time is advanced by one step in step S8, the process returns to step S4, and the same processing procedure is repeated.

  FIG. 8 shows a time-series flow when the above processing is executed for the hybrid model description shown in FIG. At t = 0, the initial state is established. At t = 0, an event Left occurs, the continuous system equation is switched, and at t = 100, an event E occurs, and additional processing is executed. Between these events, a continuous simulation is executed.

  In order for the hybrid model simulation execution unit 102 to cooperate with the mechanism control software simulator to execute the simulation efficiently as a whole, the execution order of each step constituting the simulation must be appropriately and efficiently controlled. .

  As described above, conventionally, due to the characteristics of the hybrid model description language (for example, the HCC language) (it is not known which line is executed first), programming is performed so as to appropriately and efficiently control the execution order. Is an extremely difficult task that requires extremely advanced techniques. In some cases, instead of merely treating the value of a variable, processing of a hybrid model is performed after substituting information obtained from the outside into a variable. In this case, special external functions related to the interface with the outside must be prepared, and these must be described by the model creator.

  On the other hand, in the embodiment of the present invention, the hybrid model simulation executing unit 102 is constructed according to the series of processes illustrated in FIG. 7 and configured to execute the simulation, so that the above problem can be avoided. That is, a software part corresponding to communication with the outside (process) such as a mechanism control software simulator can be described as additional processing in a hybrid model in a programming language such as C language, and its function is automatically executed by the simulation. Incorporated in

  According to the embodiments of the present invention, it is possible to flexibly model and program a complicated simulation procedure. More specifically, the present embodiment makes it possible to include a description of an additional process related to cooperation with the outside in a part of the hybrid model description. Therefore, since it is possible to easily construct a variety of sophisticated simulation models, the applicable range of the simulation can be expanded.

(2nd Embodiment)
The second embodiment of the present invention relates to cooperation between mechanism control software and a simulator of mechanism control software. FIG. 9 is a block diagram showing a schematic configuration of a mechanism simulator according to the second embodiment of the present invention. The mechanism simulator of the present embodiment includes a hybrid model preprocessing unit 201 and a hybrid model simulation execution unit 102, as in the first embodiment. The control signal 106 shown in the figure is input / output via a port between the mechanism control software or a simulator of the mechanism control software and the additional processing execution unit 205 of the hybrid model simulation execution unit 102.

  In the present embodiment, the input / output of the control signal 106 can be an additional process, and the description can be included in the hybrid model description 2104.

  FIG. 10 is a diagram illustrating an example of the content of the hybrid model description 2104 according to the second embodiment. The outport function is an API function for writing data to any of the port IDs for an external control system. The inport function is an API function for reading data from a port ID. Here, the external control system corresponds to mechanism control software or a simulator of mechanism control software.

  Lines 11 to 18 are described in C language. setDataToCtrl is a function that sets the arguments num and data to the outport function. The GetDataFromCtrl function sets the ID of the argument num-th in the import function and returns the acquired data as a return value.

  In lines 23 and 26, the setDataToCtrl function and the getDataFromCtrl function are associated with the events E1 and E2, respectively. When the event E1 occurs, the setDataToCtrl function is executed, and when the event E2 occurs, the getDataFromCtrl function is executed.

  In the 24th line, data x is converted to an integer type for control ID number 1 and set. On the 27th line, data obtained from the control signal 106 is forcibly set as the data x.

  As described above, in this hybrid simulation, a description for cooperating with an external control target during the simulation can be easily described on the same source. Naturally, the simulation result differs depending on the state of the control target.

  FIG. 11 is a flowchart showing the operation of the mechanism simulator according to the second embodiment of the present invention. When an event occurs, it is the same as the first embodiment in that the type is specified and the processing is distributed according to the type of the event. This embodiment is different from the first embodiment in that not only the state transition in the hybrid model but also the processing related to the interface with the external control object is controlled in a unified manner through the event. There is an advantage that the configuration relating to the cooperative simulation with control software or the like is simplified.

  First, as shown in FIG. 11, the hybrid model description 2104 is input to the control information analysis unit 110, and syntax analysis of the hybrid model is performed (step S1). The control information analysis unit 110 generates a model equation registration program 202, an event control program 203, and a simulation execution additional processing program 204. The equation syntax analyzer 112 based on the model equation registration program 202 converts the continuous system equation description data into a data structure that can execute a simulation, and registers the data in the equation data storage 114 (step S2).

  Thus, the pre-processing for executing the simulation is completed, and the process proceeds to the stage of executing the simulation.

  In step S4, it is detected whether an event has occurred. If an event has occurred, control proceeds to step S5. If no event has occurred, the process proceeds to step S6.

  In step S5, the type of the event that has occurred is determined. If the event type is an event related to a continuous system equation, in step S9, it is determined whether or not it is necessary to switch the continuous system equation in accordance with the state transition. If it is necessary to switch the equation, in step S10, the active continuous equation is switched by operating the valid / invalid flag. If it is not necessary to switch the equation, control proceeds to step S6.

  If the type of event that has occurred is an event related to data transmission, data is transmitted to the external control target in step S11. This transmission data is assumed to be status information of a sensor attached to the target mechanism. If the type of event that has occurred is an event related to data reception, data is received from the external control target in step S12.

  In step S6, the continuous system simulation unit 103 performs numerical integration.

  Next, an end condition is determined in step S7. Here, it is determined whether or not the time has reached a predetermined simulation end time. When the simulation end time is reached, the simulation execution ends. Until then, the time is advanced by one step in step S8, the process returns to step S4, and the same processing procedure is repeated.

  Note that the present invention is not limited to the above-described embodiment as it is, and can be embodied by modifying constituent elements in an implementation stage without departing from the scope of the invention. Various inventions can be formed by appropriately combining a plurality of constituent elements disclosed in the above embodiments. For example, some components may be deleted from all the components shown in the embodiment. Further, components of different embodiments may be appropriately combined.

FIG. 1 is a block diagram showing a schematic configuration of a mechanism simulator according to a first embodiment of the present invention. The figure which shows a certain state of the cylinder apparatus which concerns on the specific example for demonstrating a hybrid model description. The figure which shows another state of the cylinder device which concerns on the specific example for demonstrating a hybrid model description. The figure which shows the state transition of the cylinder apparatus which concerns on the specific example for demonstrating a hybrid model description. The figure which shows the content of the hybrid model description. FIG. 4 is an explanatory diagram of an internal data expression obtained as a result of parsing one continuous system equation. 4 is a flowchart showing a processing procedure of a mechanism simulation according to the first embodiment of the present invention. Explanatory drawing of the time-series flow of mechanism simulation. FIG. 7 is a block diagram showing a schematic configuration of a mechanism simulator according to a second embodiment of the present invention. FIG. 9 is a view showing contents of a hybrid model description according to the second embodiment of the present invention. 9 is a flowchart illustrating a processing procedure of a mechanism simulation.

Explanation of reference numerals

104: hybrid model description, 201: hybrid model preprocessing unit, 110: control information analysis unit, 102: hybrid model simulation execution unit, 103: continuous system simulation unit, 111: event processing unit, 112: equation syntax analysis unit, 115 ... Continuous system equation switching unit, 205 ... Additional processing execution unit, 105 ... Variable value time history storage unit

Claims (20)

A simulation method for simulating the behavior of a target mechanism along a time axis based on description data using a hybrid model,
The description data is analyzed to extract a description of a continuous system equation included in the description data, a description of switching of the continuous system equation according to a state transition, and a description of a process other than the process represented by the continuous system equation. Analysis steps to perform,
A first program generation step of generating a first program based on the description of the continuous system equation extracted in the analysis step;
A second program generation step of generating a second program based on a description regarding switching of continuous system equations accompanying the state transition extracted in the analysis step;
A third program generation step of generating a third program based on a description related to processing other than the processing represented by the continuous system equation extracted in the analysis step;
A conversion step of converting the continuous system equation into a simulation-executable data structure by executing the first program;
By executing the second program, a switching step of switching between valid and invalid of the continuous system equation according to occurrence of an event;
A simulation that solves the continuous system equation by numerical integration along a time axis using the data structure corresponding to the continuous system equation validated in the switching step, and outputs data representing behavior of the mechanism. A simulation execution step to be executed;
Performing a process other than the process represented by the continuous system equation by executing the third program. Detecting the occurrence of an event;
If the occurrence of the event is detected, determining whether the event is an event related to the third program;
Calling the third program for execution if the event is determined to be an event associated with the third program;
The simulation method according to claim 1, comprising: 3. The method according to claim 2, wherein the third program includes a process for inputting and outputting a control signal to and from an external device including mechanism control software for controlling the mechanism via an input / output port. Simulation method. The simulation method according to claim 1, wherein the event includes an evaluation result of an internal variable of the mechanism. A simulation program that causes a computer to execute a procedure for simulating the behavior of a target mechanism along a time axis based on description data using a hybrid model,
The description data is analyzed to extract a description of a continuous system equation included in the description data, a description of switching of the continuous system equation according to a state transition, and a description of a process other than the process represented by the continuous system equation. Analysis procedure
A first program generation procedure for generating a first program based on the description of the continuous system equation extracted in the analysis step;
A second program generation procedure for generating a second program based on a description about switching of a continuous system equation accompanying the state transition extracted in the analysis step;
A third program generation procedure for generating a third program based on a description of a process other than the process represented by the continuous system equation extracted in the analysis step;
A conversion procedure for converting the continuous system equation into a simulation-executable data structure by executing the first program;
By executing the second program, a switching procedure for switching between enabling and disabling the continuous system equation according to the occurrence of an event;
A simulation that solves the continuous system equation by numerical integration along a time axis using the data structure corresponding to the continuous system equation validated in the switching step, and outputs data representing behavior of the mechanism. A simulation execution procedure to be executed;
A simulation program for causing a computer to execute a process execution procedure for executing a process other than the process represented by the continuous system equation by executing the third program. Detecting the occurrence of an event;
If the occurrence of the event is detected, determining whether the event is an event related to the third program;
Calling the third program for execution if the event is determined to be an event associated with the third program;
The simulation program according to claim 5, further comprising: 7. The method according to claim 6, wherein the third program includes a procedure for inputting / outputting a control signal to / from an external device including mechanism control software for controlling the mechanism via an input / output port. Simulation program. The simulation program according to claim 5, wherein the event includes an evaluation result of an internal variable of the mechanism. In a hybrid model analysis method for analyzing a hybrid model used for simulating the behavior of a mechanism along a time axis,
An analysis step of extracting a description of a continuous system equation, a description of a state transition, and a description of an additional process from the description of the hybrid model,
A program that is called in the execution of the simulation and generates a first program based on the description regarding the continuous system equation, a second program based on the description regarding the state transition, and a third program based on the description regarding the additional processing. Generating step;
A hybrid model analysis method comprising: 10. The method according to claim 9, wherein the description relating to the additional processing includes a first description representing the content of the additional processing and a second description controlling execution of the additional processing in response to occurrence of an event. The described hybrid model analysis method. The program generating step includes a step of generating the third program from the first description, and a step of adding a program based on the second description to the second program. The hybrid model analysis method according to claim 10. In a program that analyzes a hybrid model used to simulate the behavior of a mechanism along the time axis,
An analysis procedure for extracting a description about a continuous system equation, a description about a state transition, and a description about an additional process from the description of the hybrid model,
A program that is called in the execution of the simulation and generates a first program based on the description regarding the continuous system equation, a second program based on the description regarding the state transition, and a third program based on the description regarding the additional processing. Generation procedure,
A hybrid model analysis program for causing a computer to execute. 13. The method according to claim 12, wherein the description relating to the additional processing includes a first description representing the content of the additional processing, and a second description controlling execution of the additional processing in response to occurrence of an event. The described hybrid model analysis program. The program generation procedure includes a procedure of generating the third program from the first description, and a procedure of adding a program based on the second description to the second program. A hybrid model analysis program according to claim 13. A simulation method that simulates the behavior of a mechanism along a time axis using a hybrid model consisting of a continuous system model represented by a continuous system equation, a state transition model representing a state transition accompanying an event occurrence, and an additional process. At
Storing the continuous system model in storage means;
An event processing step of determining whether any of the events described in the state transition model has occurred;
A determining step of determining whether the event is related to the additional processing;
Performing an additional process associated with the event if the event is associated with the additional process;
A simulation step of performing a continuous system simulation based on a continuous system equation effective in the continuous system model stored in the storage means;
A simulation method comprising: 16. The simulation method according to claim 15, wherein the additional processing includes processing for inputting / outputting a control signal to / from an external device including mechanism control software for controlling the mechanism via an input / output port. . The simulation method according to claim 15, further comprising a step of switching the effective continuous system equation according to a state transition based on the state transition model. It has a hybrid model consisting of a continuous system model represented by a continuous system equation, a state transition model representing a state transition associated with the occurrence of an event, and additional processing. A simulation program based on the model,
A storage procedure for storing the continuous system model;
An event processing procedure for determining whether any of the events described in the state transition model has occurred;
A determination procedure for determining whether the event is related to the additional processing,
If the event is related to the additional processing, an execution procedure for performing the additional processing associated with the event;
A simulation procedure for executing a continuous system simulation based on a continuous system equation effective in the continuous system model stored by the storage procedure;
Simulation program for causing a computer to execute. 19. The simulation program according to claim 18, wherein the additional processing includes processing for inputting / outputting a control signal to / from an external device including mechanism control software for controlling the mechanism via an input / output port. . 19. The simulation program according to claim 18, further comprising a switching procedure for switching the effective continuous system equation in accordance with a state transition based on the state transition model.

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