Method and system for simulating complex systems by integrating system dynamics models

• US 8,260,587 B2
• Filed: 09/16/2008
• Issued: 09/04/2012
• Est. Priority Date: 09/16/2008
• Status: Active Grant

• Current Assignee: Raytheon Company (Rtx Corporation)
• Original Assignee: Raytheon Company (Rtx Corporation)
• Inventors: Sanchez, Hernando, Gallerani, Andrew
• Primary Examiner(s): Jacob, Mary C
• Assistant Examiner(s): Chad, Aniss
• Application Number:
  US12/211,332
• Publication Number:
  US 20100070251A1
• Time in Patent Office: 1,449 Days
• Field of Search: 703/2, 703/6
• US Class Current: 703/2
• CPC Class Codes: G06F 30/15 Vehicle, aircraft or watercraft design
• CPC Class Codes: G06F 30/20 Design optimisation, verification or simulation optimisation, verification or simulation of circuit designs G06F30/30

Abstract

A method for simulating complex systems over time using a system dynamics approach is provided including defining a first model of a complex system, the first model having a first model variable; defining a second model of the complex system, the second model having a second model variable; executing the first model by modifying the first model variable to obtain a first model output; executing the second model by passing the first model output to the second model and modifying the second model variable based the first model output to obtain a second model output; defining a simulation result based on the first and second model outputs; and outputting the simulation result. Furthermore, the first model is either a non-subscripted system dynamics model or a subscripted system dynamics model, and the second model is either a non-scripted system dynamics model or a scripted system dynamics model.

Claims

1. A method for simulating complex systems over time comprising:

defining a first model of a complex system, the first model having a first model variable;

defining a second model of the complex system, the second model having a second model variable;

executing the first model by modifying the first model variable to obtain a first model output;

executing the second model by passing the first model output to the second model and modifying the second model variable based the first model output to obtain a second model output;

defining a simulation result based on the first and second model outputs; and

outputting the simulation result,

wherein the first model is at least one of a non-subscripted system dynamics model representing an overall behavior model of the complex system without arrays or a subscripted system dynamics model representing an overall behavior model of the complex system with arrays, and the second model is at least one of a non-subscripted system dynamics model representing an overall behavior model of the complex system without arrays or a subscripted system dynamics model representing an overall behavior model of the complex system with arrays.

2. The method of claim 1, further comprising:

reexecuting the first model by passing the second model output to the first model and modifying the first model variable based the second model output to obtain the simulation result.

3. The method of claim 1, wherein the first model variable is a plurality of first model variables to describe a behavior of the first model, and the second model variable is a plurality of second model variables to describe a behavior of the second model.

4. The method of claim 1, wherein executing the first model further includes executing the first model over a first model time period, and executing the second model further includes executing the second model over a second model time period.

5. The method of claim 4, wherein the first model time period is different than the second model time period.

6. The method of claim 5, wherein executing the first and second model is controlled by at least one loop program based on the first and second model time period.

7. The method of claim 5, wherein passing the first and second model output is controlled by a data exchanger.

8. The method of claim 4, wherein executing the first model includes executing the first model a number of first model loop times and for each execution of the first model, the second model is executed a number of second model loop times.

9. The method of claim 8, wherein the first model output is passed to the second model, and the second model output is passed to the first model after executing the second model the number of second model loop times.

10. The method of claim 1, wherein outputting the simulation results includes displaying the simulation results.

11. The method of claim 1 wherein the first model is one of a non-subscripted system dynamics model representing an overall behavior model of the complex system without arrays or a subscripted system dynamics model representing an overall behavior model of the complex system with arrays, and the second model is the other one of the non-subscripted system dynamics model or the subscripted system dynamics model.

12. A method for simulating complex systems over time comprising:

defining a first system dynamics model (F-SDM) of a complex system, the F-SDM having at least one first variable;

defining a second system dynamics model (S-SDM) of the complex system, the S-SDM having at least one second variable;

executing the F-SDM by modifying the at least one first variable according to at least one F-SDM behavior to obtain a first output;

executing the S-SDM by passing the first output to the S-SDM and modifying the at least one second model variable according to at least one S-SDM behavior and the first output to obtain a second output;

defining a simulation result based on at least one of the first or second outputs; and

outputting the simulation result,

wherein the F-SDM is one of a non-subscripted system dynamics model representing an overall behavior model of the complex system without arrays or a subscripted system dynamics model representing an overall behavior model of the complex system with arrays, and the S-SDM is one of a non-subscripted system dynamics model representing an overall behavior model of the complex system without arrays or a subscripted system dynamics model representing an overall behavior model of the complex system with arrays.

13. The method of claim 12, wherein executing the F-SDM and the S-SDM is controlled by at least one loop program and passing the first and second outputs is controlled by a data exchanger.

14. The method claim 13, wherein the S-SDM is at least two second system dynamics models and the data exchanger aggregates the at least one second output for the at least two second system dynamics models, and the data exchanger disaggregates the at least one first output.

15. The method of claim 12 wherein the F-SDM is one of a non-subscripted system dynamics model representing an overall behavior model of the complex system without arrays or a subscripted system dynamics model representing an overall behavior model of the complex system with arrays, and the S-SDM is the other one of the non-subscripted system dynamics model or the subscripted system dynamics model.

16. An article, comprising:

a non-transitory machine-readable medium that stores executable instructions that cause a machine to;

define a first model of a complex system, the first model having a first model variable;

define a second model of the complex system, the second model having a second model variable;

execute the first model by modifying the first model variable to obtain a first model output;

execute the second model by passing the first model output to the second model and modifying the second model variable based the first model output to obtain a second model output;

define a simulation result based on the first and second model outputs; and

output the simulation result,

wherein the first model is at least one of a non-subscripted system dynamics model representing an overall behavior model of the complex system without arrays or a subscripted system dynamics model representing an overall behavior model of the complex system with arrays, and the second model is at least one of a non-subscripted system dynamics model representing an overall behavior model of the complex system without arrays or a subscripted system dynamics model representing an overall behavior model of the complex system with arrays.

17. The article according to claim 16, wherein the executable instructions further cause a machine to:

reexecute the first model by passing the second model output to the first model and modifying the first model variable based the second model output to obtain the simulation result.

18. The article according to claim 16, wherein the first model variable is a plurality of first model variables to describe a behavior of the first model, and the second model variable is a plurality of second model variables to describe a behavior of the second model.

19. The article according to claim 16, wherein the first model executes over a first model time period, and the second model executes over a second model time period.

20. The article according to claim 19, wherein the first model time period is different than the second model time period.

21. The article according to claim 20, wherein the executable instruction further cause a machine to execute at least one loop program to execute the first and second model based on the first and second model time periods.

22. The article according to claim 20, wherein the executable instructions further cause a machine to execute a data exchanger to pass the first and second model outputs.

23. The article according to claim 19, wherein the first model executes a number of first model loop times and for each execution of the first model, the second model executes a number of second model loop times.

24. The article according to claim 23, wherein the first model output is passed to the second model, and the second model output is passed to the first model after execution of the second model the number of second model loop times.

25. The article according to claim 16, wherein the output of the simulation results enables a display of the simulation results.

26. The article of claim 16 wherein the first model is one of a non-subscripted system dynamics model representing an overall behavior model of the complex system without arrays or a subscripted system dynamics model representing an overall behavior model of the complex system with arrays, and the second model is the other one of the non-subscripted system dynamics model or the subscripted system dynamics model.