System and method for analyzing different scenarios for operating and designing equipment

• US 6,532,426 B1
• Filed: 09/17/1999
• Issued: 03/11/2003
• Est. Priority Date: 09/17/1999
• Status: Expired due to Term

• Current Assignee: Gula Consulting Limited Liability Company (Intellectual Ventures LLC)
• Original Assignee: The Boeing Co.
• Inventors: Hooks, Dean C., Dubuque, Mark W., Simon, Keith D.
• Primary Examiner(s): Barlow, John
• Assistant Examiner(s): LE, JOHN H
• Application Number:
  US09/398,672
• Time in Patent Office: 1,271 Days
• Field of Search: 702/34, 702/81, 702/181, 702/182, 702/183, 702/184, 702/185, 700/9, 700/49, 700/79, 700/117, 703/7, 714/25, 714/26, 704/45, 704/46
• US Class Current: 702/81
• CPC Class Codes: G06F 17/18 for evaluating statistical data , e.g. average values, frequency distributions, probability functions, regression analysis forecasting specially adapted for a specific administrative, business or logistic context G06Q10/04
• CPC Class Codes: G06Q 10/06 Resources, workflows, human or project management; Enterprise or organisation planning; Enterprise or organisation modelling

Abstract

An equipment module is analyzed through the use of an array of failure probability values. The array of failure probability values provides an indication of the probability that the equipment module will fail at a plurality of different times. A cost of operating the equipment module is determined by calculating the cost of operating the equipment module at each of the different times using the array of failure probability values, so that the cost calculated at each of the different times is proportional to the probability that the equipment module will fail at the respective time. The cost of operating the equipment module at each of the different times can include a recurring cost value and a non-recurring cost value. An additional probability can be utilized when calculating the cost of operating the equipment module. A maintenance time can be determined, and the costs are calculated in view of maintenance performed at the maintenance time. Different first and second, or first second, third and fourth, scenarios of operating the equipment module can be specified and compared. The present invention advantageously facilitates the selection between numerous scenarios for designing and operating an equipment module by quantifying the relative benefits of the scenarios.

Claims

1. A method for analyzing an equipment module, the method comprising:

providing an array of failure probability values for the equipment module, wherein the array of failure probability values provides an indication of the probability that the equipment module will fail at a plurality of different times; and

determining a cost of operating the equipment module, comprising calculating the cost of operating the equipment module at each of the different times using the array of failure probability values, so that the cost calculated at each of the different times is proportional to the probability that the equipment module will fail at the respective time.

2. A program module stored on computer-readable medium and which, when executed by a computer, performs the method of claim 1.

3. A method for analyzing an equipment module according to claim 1, wherein:

the different times comprises a series of times;

the step of calculating the cost comprises calculating a series of first costs that respectively correspond to the series of times; and

the method further comprises identifying a maintenance time, comprising calculating a series of second costs that respectively correspond to the series of times, wherein each second cost is calculated by dividing a respective sum by the respective time corresponding to the second cost, for each second cost the respective sum includes at least the first cost that corresponds to the respective time of the second cost, and the maintenance time is the time of the series of times that corresponds to the smallest second cost of the series of second costs.

4. A program module stored on computer-readable medium and which, when executed by a computer, performs the method of claim 3.

5. A method for analyzing an equipment module according to claim 1, wherein:

the method further comprises providing a predetermined maintenance time, which indicates a time at which maintenance should be performed on the equipment module, wherein the plurality of different times comprises a series of times designated as a first time through a last time, respectively, and the maintenance time is between the first time and the last time;

the step of calculating the cost of operating the equipment module at each of the different times comprises calculating a series of costs designated as a first cost through a last cost, wherein the series of costs respectively correspond to the series of times, and the step of calculating the costs comprises calculating at least some of the costs, which correspond to times after the maintenance time, as being proportional to probabilities, which are provided by the array of failure probability values, that correspond to times prior to the maintenance time.

6. A method for analyzing an equipment module according to claim 1, further comprising providing at least one predetermined recurring cost value and at least one predetermined non-recurring cost value, wherein the step of calculating the cost of operating the equipment module at each of the different times comprises summing at least the recurring cost value and the non-recurring cost value.

7. A method for analyzing an equipment module according to claim 6, wherein:

the recurring cost value is selected from the group consisting of;

cost of the equipment module,

costs incurred due to failure of the equipment module,

costs of prognostic hardware for the equipment module, and

costs of prognostic procedures for the equipment module; and

the non-recurring cost value is selected from the group consisting of costs of designing prognostic capabilities into the equipment module.

8. A method for analyzing an equipment module according to claim 1, further comprising providing a predetermined probability value, wherein the step of calculating the cost of operating the equipment module at each of the different times comprises using the predetermined probability value to calculate a product.

9. A method for analyzing an equipment module according to claim 8, wherein the predetermined probability value is selected from the group consisting of:

a probability that the equipment module will be incorrectly identified as needing to be refurbished;

a probability that the equipment module will be incorrectly identified as needing to be replaced;

a probability that no notification of a necessary refurbishment will be provided for the equipment module, such that the equipment module fails without warning; and

a probability that no notification of a necessary replacement will be provided for the equipment module, such that the equipment module fails without warning.

10. A method according to claim 1, further comprising:

specifying a first scenario of operating the equipment module, wherein the determining a cost of operating the equipment module comprises determining a cost of operating the equipment module in accordance with the first scenario, and the calculating the cost of operating the equipment module at each of the different times using the array of failure probability values comprises calculating the cost of operating the equipment module in accordance with the first scenario at each of the different times using the array of failure probability values, so that the cost calculated at each of the different times for the first scenario is proportional to the probability that the equipment module will fail at the respective time;

specifying a second scenario of operating the equipment module, wherein the second scenario is different from the first scenario;

determining a cost of operating the equipment module in accordance with the second scenario, comprising calculating the cost of operating the equipment module in accordance with the second scenario at each of the different times using the array of failure probability values, so that the cost calculated at each of the different times for the second scenario is proportional to the probability that the equipment module will fail at the respective time; and

determining a first value that quantifies the difference between the cost of operating the equipment module in accordance with the first scenario and the cost of operating the equipment module in accordance with the second scenario.

11. A program module stored on computer-readable medium and which, when executed by a computer, performs the method of claim 10.

12. A method according to claim 10, wherein the first and second scenarios are selected from a group consisting of an operate to failure approach, a prognostic approach, and a maintenance approach.

13. A method according to claim 10, wherein both the first and second scenarios are defined by at least one variable, and the specifying of the first scenario comprises specifying a first value for the variable and the specifying of the second scenario comprises specifying a second value for the variable that is different from the first value.

14. A program module stored on computer-readable medium and which, when executed by a computer, performs the method of claim 13.

15. A method according to claim 13, wherein the variable is selected from a group consisting of:

cost of the equipment module;

costs incurred due to failure of the equipment module;

number of equipment modules;

total amount of time that a system incorporating the equipment module is expected to operate in the entire life of the system;

average length of time that the system incorporating the equipment module operates, wherein the system operates intermittently; and

total number of the systems that will be produced.

16. A method according to claim 10, wherein each of the first and second scenarios comprises a prognostic approach which is defined by at least one variable, and the specifying of the first scenario comprises specifying a first value for the variable and the specifying of the second scenario comprises specifying a second value for the variable that is different from the first value.

17. A method according to claim 16, wherein the variable is selected from a group consisting of:

cost of prognostic hardware for the equipment module;

cost of prognostic procedures for the equipment module;

cost of designing prognostic capabilities into the equipment module;

a probability that the equipment module will be incorrectly identified as needing to be refurbished;

a probability that the equipment module will be incorrectly identified as needing to be replaced;

a probability that no notification of a necessary refurbishment will be provided for the equipment module, such that the equipment module fails without warning; and

a probability that no notification of a necessary replacement will be provided for the equipment module, such that the equipment module fails without warning.

18. A method according to claim 10, further comprising:

specifying a third scenario of operating the equipment module;

specifying a fourth scenario of operating the equipment module, wherein the third scenario is different from the fourth scenario;

determining a cost of operating the equipment module in accordance with the third scenario, comprising calculating the cost of operating the equipment module in accordance with the third scenario at each of the different times using the array of failure probability values, so that the cost calculated at each of the plurality of different times for the third scenario is proportional to the probability that the equipment module will fail at the respective time;

determining a cost of operating the equipment module in accordance with the fourth scenario, comprising calculating the cost of operating the equipment module in accordance with the fourth scenario at each of the different times using the array of failure probability values, so that the cost calculated at each of the plurality of different times for the fourth scenario is proportional to the probability that the equipment module will fail at the respective time;

determining a second value that quantifies the difference between the cost of operating the equipment module in accordance with the third scenario and the cost of operating the equipment module in accordance with the fourth scenario; and

quantifying the difference between the first value and the second value.

19. A program module stored on computer-readable medium and which, when executed by a computer, performs the method of claim 18.

20. A method according to claim 18, wherein each of the first, second, third and fourth scenarios are defined by at least one variable, and the specifying of the first and second scenarios comprises specifying a first value for the variable and the specifying of the third and fourth scenarios comprises specifying a second value for the variable that is different from the first value.