Simulation system using model

• US 6,304,835 B1
• Filed: 09/07/1999
• Issued: 10/16/2001
• Est. Priority Date: 03/31/1998
• Status: Expired due to Term

• Current Assignee: Mazda Motor Corporation
• Original Assignee: Mazda Motor Corporation
• Inventors: Harada, Yasuhiro, Komori, Satoshi, Arakawa, Hiroyuki, Hiramatsu, Shigeki, Sumida, Shizuo
• Primary Examiner(s): Teska, Kevin J.
• Assistant Examiner(s): JONES, HUGH M
• Application Number:
  US09/390,654
• Time in Patent Office: 770 Days
• Field of Search: 703/6, 703/7, 703/8, 703/9
• US Class Current: 703/7
• CPC Class Codes: B60W 2050/0037 Mathematical models of vehicle sub-units
• CPC Class Codes: B60W 2050/0039 of the propulsion unit
• CPC Class Codes: B60W 2050/0041 of the drive line
• CPC Class Codes: G06G 7/64 for non-electric machines, e.g. turbine

Abstract

This invention proposes a simulation apparatus which can simulate by easily coping with changes in component and model. A simulation apparatus simulates, using a system model, the dynamic performance of a target apparatus to be simulated, which includes a driving source and is constructed by a plurality of units for transmitting the driving force output from the driving source, and expresses the target apparatus by functional and data models. The functional model expresses each of units that construct the target apparatus by exchange of energy by the dynamic performance of that unit, and a parameter which determines that dynamic performance. The parameter for each unit is computed using static characteristic data read out from a memory, thus expressing each unit as a data model.

Claims

1. A simulation apparatus simulating dynamic performance of a target apparatus, which includes a plurality of units performing non-linear operation and energy is transmitted therebetween, said simulation apparatus comprising:

functional modeling means for modeling each unit by functional models, including at least a first parameter that determines dynamic performance of each respective unit, in which exchange of energy according to the dynamic performance of each unit is defined by product of a potential variable that expresses a potential of the energy and a flow variable that expresses a flow of the energy and coupling each of the functional models via a pair comprising the potential variable and the flow variable;

data storage means for storing, in advance, non-linear characteristic data of each unit as functions or tables;

data modeling means for, when simulation of the dynamic performance of the target apparatus is performed, generating, by using pre-stored mechanism models depending on an actual mechanism of each unit, at least a second parameter of each unit on the basis of the characteristic data for the respective unit read from said data storage means at every predetermined sampling period of time; and

simulation control means for simulating the dynamic performance of the target apparatus by setting the generated second parameter as the first parameter of said coupled functional models at each predetermined sampling period of time and outputting a simulation result of the dynamic performance of the target apparatus.

2. The apparatus according to claim 1, wherein each first parameter to be set into said coupled functional models represents at least one of a mass, spring, and damper.

3. The apparatus according to claim 1, wherein said functional modeling means models the functional models of each unit by a matrix.

4. The apparatus according to claim 1, wherein the functional models of each unit is defined by a system equation.

5. The apparatus according to claim 1, wherein the second parameter to be set as the first parameter includes a state variable of each unit, and a state change variable upon infinitesimal state transition.

6. The apparatus according to claim 1, wherein a plurality of said data modeling means are provided in correspondence with types of the units.

7. The apparatus according to claim 1, wherein the first parameter is constant for the functional models, and

said data modeling means generates and sets the second parameter at every predetermined sampling period of time so that the second parameter can be considered as the constant between the sampling period of time.

16. The apparatus according to claim 1, wherein the target apparatus is a power train, and

the plurality of units correspond to at least a driving source and transmitting units transmitting a driving force output from the driving source.

18. The apparatus according to claim 1, wherein the non-linear characteristic data represents a characteristic curve, and

said data modeling means calculates a tangent to the characteristic curve and generates, as the second parameter, a slope of the tangent and an intercept of the tangent.

19. The apparatus according to claim 16, wherein one of the transmitting units further corresponds to a planetary gear train that provides at least a total of three input portions and output portions, and

said functional model means models, as the functional model of the planetary gear train, a gear model that includes at least a first data module, which corresponds to input/output lines to connect the input portions and the output portions, and a second data module, functioning in parallel with the first data module, that determines the dynamic performance of the gear model.

20. The apparatus according to claim 19, wherein the gear model further includes a third data module connected to the input/output lines and functioning as a variable control gain of the gear model.

21. The apparatus according to claim 19, wherein the gear model further includes a fourth data module functioning as a differential term of an inertia moment of a shaft provided in the planetary gear train.

8. A simulation method simulating dynamic performance of a target apparatus, which includes a plurality of units performing non-linear operation and energy is transmitted therebetween, said method comprising:

modeling each unit by functional models, including at least a first parameter that determines dynamic performance of each respective unit, in which exchange of energy according to the dynamic performance of each unit is defined by product of a potential variable that expresses a potential of the energy and a flow variable that expresses a flow of the energy and coupling each of the functional models via a pair comprising the potential variable and the flow variable;

storing, in advance, non-linear characteristic data of each unit, as functions or tables, in a data storage;

when simulation of the dynamic performance of the target apparatus is performed, generating, by using pre-stored mechanism models depending on an actual mechanism of each unit, at least a second parameter of each unit on the basis of the characteristic data for the respective unit read from said data storage at every predetermined sampling period of time; and

simulating the dynamic performance of the target apparatus by setting the generated second parameter as the first parameter of said coupled functional models at each predetermined sampling period of time and outputting a simulation result of the dynamic performance of the target apparatus.

10. The method according to claim 8, wherein the functional model of each unit is a matrix.

11. The method according to claim 8, wherein the first parameter is a constant of the functional models, and

the second parameter is generated and set at each of the predetermined sampling period of time so that the set second parameter can be considered as the constant between the sampling period of time.

12. The method according to claim 8, wherein the second parameter to be set as the first parameter includes a state variable of each unit, and a state change variable upon infinitesimal state transition.

17. The method according to claim 8, wherein the target apparatus is a power train, and

the plurality of units correspond to at least a driving source and transmitting units transmitting a driving force output from the driving source.

22. The method according to claim 17, wherein one of the transmitting units further corresponds to a planetary gear train that provides at least a total of three input portions and output portions, and

said modeling models, as the functional model of the planetary gear train, a gear model that includes at least a first data module, which corresponds to input/output lines to connect the input portions and the output portions, and a second data module, functioning in parallel with first data module, that determines the dynamic performance of the gear model.

23. The method according to claim 22, wherein the gear model further includes a third data module, which is connected to the input/output lines and functions as a variable control gain of the gear model.

24. The method according to claim 22, wherein the gear model further includes a fourth data module, which functions as a differential term of an inertia moment of a shaft provided in the planetary gear train.

28. The method according to claim 8, wherein the non-linear characteristic data represents a characteristic curve, and

said modeling calculates a tangent to the characteristic curve and generates, as the second parameter, a slope of the tangent and an intercept of the tangent.

9. A computer readable storage medium storing a computer program for making a computer perform a simulation of dynamic performance of a target apparatus, which includes a plurality of units performing non-linear operation and energy is transmitted therebetween, comprising:

modeling each unit by functional models, including at least a first parameter that determines dynamic performance of each respective unit, in which exchange of energy according to the dynamic performance of each unit is defined by product of a potential variable that expresses a potential of the energy and a flow variable that expresses a flow of the energy and coupling each of the functional models via a pair comprising the potential variable and the flow variable;

storing, in advance, non-linear characteristic data of each unit, as functions or tables, in a data storage;

when simulation of the dynamic performance of the target apparatus is performed, generating, by using pre-stored mechanism models depending on an actual mechanism of each unit, at least a second parameter of each unit on the basis of the characteristic data for the respective unit read from said data storage at every predetermined sampling period of time;

simulating the dynamic performance of the target apparatus by setting the generated second parameter as the first parameter of said coupled functional models at each predetermined sampling period of time and outputting a simulation result of the dynamic performance of the target apparatus.

13. A computer readable storage medium according to claim 9, wherein the functional model of each unit is a matrix.

14. A computer readable storage medium according to claim 9, wherein the first parameter is a constant of the functional models, and

the second parameter is generated and set at each of the predetermined sampling period of time so that the set second parameter can be considered as the constant between the sampling period of time.

15. A computer readable storage medium according to claim 9, wherein the second parameter to be set as the first parameter includes a state variable of each unit, and a state change variable upon infinitesimal state transition.

25. A computer readable storage medium according to claim 9, wherein one of the transmitting units further corresponds to a planetary gear train that provides at least a total of three input portions and output portions, and

said modeling models, as the functional model of the planetary gear train, a gear model that includes at least a first data module, which corresponds to input/output lines to connect the input portions and the output portions, and a second data module, functioning in parallel with first data module, that determines the dynamic performance of the gear model.

26. A computer readable storage medium according to claim 25, wherein the gear model further includes a third data module, which is connected to the input/output lines and functions as a variable control gain of the gear model.

27. A computer readable storage medium according to claim 25, wherein the gear model further includes a fourth data module, which functions as a differential term of an inertia moment of a shaft provided in the planetary gear train.

29. A computer readable storage medium according to claim 9, wherein the non-linear characteristic data represents a characteristic curve, and

said modeling calculates a tangent to the characteristic curve and generates, as the second parameter, a slope of the tangent and an intercept of the tangent.

30. A computer system simulating dynamic performance of a target apparatus, which includes a plurality of units performing non-linear operation and energy is transmitted therebetween, the computer system comprising:

a storage unit storing non-linear characteristic data of each unit as functions or tables; and

a processor coupled to the storage unit, to model each unit by functional models that include at least a first parameter that determines dynamic performance of each respective unit, exchange of energy according to the dynamic performance of each unit being defined by product of a potential variable that expresses a potential of the energy and a flow variable that expresses a flow of the energy, to couple each of the functional models via a pair comprising the potential variable and the flow variable, to generate, when simulation of the dynamic performance of the target apparatus is performed and using mechanism models depending on an actual mechanism of each unit, at least a second parameter of each unit on the basis of the characteristic data read from the storage unit for the respective unit at every predetermined sampling period of time, to simulate and output a simulation result of the dynamic performance of the target apparatus by substituting the second parameter for the first parameter of said coupled functional models at each predetermined sampling period of time.