Automated constraint-based scheduling using condition-based maintenance

• US 8,560,368 B1
• Filed: 11/18/2011
• Issued: 10/15/2013
• Est. Priority Date: 11/18/2011
• Status: Active Grant

• Current Assignee: Lockheed Martin Corporation (Martin Marietta Corporation)
• Original Assignee: Lockheed Martin Corporation (Martin Marietta Corporation)
• Inventors: McMullen, David, Maity, Ashis K., Zaremby, David, Gomez, Juan M.
• Primary Examiner(s): Fleischer, Mark A
• Application Number:
  US13/299,740
• Time in Patent Office: 697 Days
• Field of Search: 705/7.13
• US Class Current: 705/7.13
• CPC Class Codes: G06Q 10/0631 Resource planning, allocation, distributing or scheduling for enterprises or organisations
• CPC Class Codes: G06Q 10/20 Administration of product repair or maintenance

Abstract

An automated constraint-based scheduler that uses condition-based information is disclosed. A scheduler module generates a maintenance schedule for one or more components. The scheduler module receives time-based maintenance information associated with a component and condition-based maintenance information that identifies a determined condition of the component. A plurality of constraints associated with performing maintenance on the component is determined. The scheduler module uses a constraint-based scheduler to generate a maintenance schedule for the component based on the time-based maintenance information, the condition-based maintenance information, and the plurality of constraints.

Claims

1. A method for generating a maintenance schedule for a plurality of components associated with a plurality of machines, the method comprising:

receiving, by a processing device, time-based maintenance information comprising a plurality of time-based work orders that originate from a first source and that identify maintenance tasks to be performed on a first plurality of components of the plurality of components;

receiving, by the processing device, condition-based maintenance information comprising a plurality of condition-based maintenance work orders that originate from a second source and that identify maintenance tasks to be performed on a second plurality of components of the plurality of components based on sensed conditions of the second plurality of components;

making a determination, by the processing device, that one of the plurality of time-based work orders and one of the plurality of condition-based maintenance work orders identify a maintenance task on a component of a same machine;

altering the one of the plurality of time-based work orders or the one of the plurality of condition-based maintenance work orders based on the determination;

determining a plurality of constraints associated with performing maintenance on the plurality of components; and

generating, using a constraint-based scheduler, the maintenance schedule for the plurality of components based on the time-based maintenance information, the condition-based maintenance information, and the plurality of constraints.

2. The method of claim 1, further comprising generating prioritization information that prioritizes the condition-based maintenance information as having a higher priority than the time-based maintenance information, and wherein generating, using the constraint-based scheduler, the maintenance schedule based on the time-based maintenance information, the condition-based maintenance information, and the plurality of constraints further comprises:

generating, using the constraint-based scheduler, the maintenance schedule based on the time-based maintenance information, the condition-based maintenance information, the plurality of constraints, and the prioritization information.

3. The method of claim 1, wherein the time-based maintenance information is stored in a preventive maintenance database, the method further comprising:

altering a time-based work order stored in the preventive maintenance database that identifies a maintenance task to be performed at a first date to reschedule the maintenance task to be performed at a second date based on the condition-based maintenance information.

4. The method of claim 1, further comprising:

determining, based on the time-based maintenance information or the condition-based maintenance information, a need for a particular part;

determining that the particular part is not in stock; and

automatically generating a message that indicates the need to order the particular part.

5. The method of claim 1, further comprising:

determining, by the processing device, at least one maintenance schedule optimization criterion comprising one of a group including a least cost criterion, a fewest mechanics criterion, and a shortest time frame criterion; and

wherein generating, using the constraint-based scheduler, the maintenance schedule based on the time-based maintenance information, the condition-based maintenance information, and the plurality of constraints further comprises;

generating, using the constraint-based scheduler, the maintenance schedule based on the time-based maintenance information, the condition-based maintenance information, the plurality of constraints, and the at least one maintenance schedule optimization criterion, wherein the maintenance schedule satisfies the at least one maintenance schedule optimization criterion.

6. The method of claim 1, wherein the condition-based maintenance information further comprises probability information identifying a probability that at least one component requires maintenance.

7. The method of claim 1, wherein altering the one of the plurality of time-based work orders or the one of the plurality of condition-based maintenance work orders based on the determination comprises deleting the one of the plurality of time-based work orders or the one of the plurality of condition-based maintenance work orders.

8. The method of claim 1, wherein the plurality of constraints comprises a precedence constraint identifying a precedence of maintenance with respect to at least two components from the plurality of components, and a resource constraint identifying a finite number of resources associated with performing maintenance on the plurality of components.

9. The method of claim 1, wherein altering the one of the plurality of time-based work orders or the one of the plurality of condition-based maintenance work orders based on the determination comprises

merging the one of the plurality of time-based work orders and the one of the plurality of condition-based maintenance work orders into a merged work order, thereby eliminating the one of the plurality of time-based work orders or the one of the plurality of condition-based maintenance work orders.

10. The method of claim 1, wherein each of the plurality of time-based work orders identifies relevant resources for performing the respective maintenance task including a time domain, a part, and a maintainer criterion,

and each of the plurality of condition-based maintenance work orders identifies relevant resources for performing the respective maintenance task including a time domain, a part and a maintainer criterion;

and

wherein generating, using the constraint-based scheduler, the maintenance schedule for the plurality of components based on the time-based maintenance information, the condition-based maintenance information, and the plurality of constraints further comprises;

generating, using the constraint-based scheduler, the maintenance schedule for the plurality of components based on the plurality of time-based work orders, the plurality of condition-based maintenance work orders, and the plurality of constraints, wherein the maintenance schedule identifies, for each of the plurality of components, a start time of a corresponding maintenance task, an end time of the corresponding maintenance task, and a particular maintainer of a plurality of maintainers for performing the corresponding maintenance task.

11. The method of claim 1, wherein altering the one of the plurality of time-based work orders or the one of the plurality of condition-based maintenance work orders based on the determination comprises assigning the one of the plurality of condition-based maintenance work orders a higher prioritization than the one of the plurality of time-based work orders.

12. A method for generating a maintenance schedule for a plurality of components, the method comprising:

receiving, by a processing device, a plurality of time-based work orders, each of the plurality of time-based work orders originating from a first source and identifying a maintenance task to be performed on a corresponding component of the plurality of components;

receiving, by the processing device, a plurality of condition-based maintenance work orders, each of the plurality of condition-based maintenance work orders originating from a second source and identifying a maintenance task to be performed on a corresponding component of the plurality of components based on sensed conditions of the plurality of components;

making a determination, by the processing device, that one of the plurality of time-based work orders and one of the plurality of condition-based maintenance work orders identify a maintenance task on a same component;

altering the one of the plurality of time-based work orders or the one of the plurality of condition-based maintenance work orders based on the determination;

prioritizing the plurality of condition-based maintenance work orders with respect to the plurality of time-based work orders to generate a prioritized list of work orders;

determining a plurality of constraints associated with performing the maintenance tasks; and

generating, using a constraint-based scheduler, the maintenance schedule for the plurality of components based on the prioritized list of work orders.

13. The method of claim 12, wherein altering the one of the plurality of time-based work orders or the one of the plurality of condition-based maintenance work orders based on the determination comprises:

merging the one of the plurality of condition-based maintenance work orders with the one of plurality of time-based work orders to create a merged work order.

14. A computing device configured to generate a maintenance schedule for a plurality of components associated with a plurality of machines, comprising:

a communication interface configured to communicate with a network; and

a processor coupled to the communication interface and configured to;

receive time-based maintenance information comprising a plurality of time-based work orders originating from a first source and that identify maintenance tasks to be performed on a first plurality of components of the plurality of components;

receive condition-based maintenance information comprising a plurality of condition-based maintenance work orders originating from a second source and that identify maintenance tasks to be performed on a second plurality of components of the plurality of components based on sensed conditions of the second plurality of components;

make a determination that one of the plurality of time-based work orders and one of the plurality of condition-based maintenance work orders identify a maintenance task on a component of a same machine;

alter the one of the plurality of time-based work orders or the one of the plurality of condition-based maintenance work orders based on the determination;

determine a plurality of constraints associated with performing maintenance on the plurality of components; and

generate, using a constraint-based scheduler, the maintenance schedule for the plurality of components based on the time-based maintenance information, the condition-based maintenance information, and the plurality of constraints.

15. The computing device of claim 14, wherein the processor is further configured to:

generate prioritization information that prioritizes the condition-based maintenance information as having a higher priority than the time-based maintenance information, and wherein to generate, using the constraint-based scheduler, the maintenance schedule based on the time-based maintenance information, the condition-based maintenance information, and the plurality of constraints the processor is further configured to;

generate, using the constraint-based scheduler, the maintenance schedule based on the time-based maintenance information, the condition-based maintenance information, the plurality of constraints, and the prioritization information.

16. The computing device of claim 14, wherein the time-based maintenance information is stored in a preventive maintenance database, the processor being further configured to:

based on the condition-based maintenance information, alter a time-based work order stored in the preventive maintenance database to specify that at least one component should be scheduled for preventive maintenance at a later date that is subsequent to an original date on which the at least one component was scheduled for the preventive maintenance prior to altering the time-based work order.

17. The computing device of claim 14, wherein the processor is further configured to:

determine at least one maintenance schedule optimization criterion comprising a criterion selected from a group including a least cost criterion, a fewest mechanics criterion, and a shortest time frame criterion; and

wherein to generate, using the constraint-based scheduler, the maintenance schedule based on the time-based maintenance information, the condition-based maintenance information, and the plurality of constraints the processor is further configured to;

generate, using the constraint-based scheduler, the maintenance schedule based on the time-based maintenance information, the condition-based maintenance information, the plurality of constraints, and the at least one maintenance schedule optimization criterion, wherein the maintenance schedule satisfies the at least one maintenance schedule optimization criterion.

18. A computer program product for generating a maintenance schedule for a plurality of components associated with a plurality of machines, the computer program product stored on a non-transitory computer-readable storage medium and including instructions configured to cause a processor to carry out the steps of:

receiving time-based maintenance information comprising a plurality of time-based work orders originating from a first source and that identify maintenance tasks to be performed on a first plurality of components of the plurality of components;

receiving condition-based maintenance information comprising a plurality of condition-based maintenance work orders originating from a second source and that identify maintenance tasks to be performed on a second plurality of components of the plurality of components based on sensed conditions of the second plurality of components;

making a determination that one of the plurality of time-based work orders and one of the plurality of condition-based maintenance work orders identify a maintenance task on a component of a same machine;

altering the one of the plurality of time-based work orders or the one of the plurality of condition-based maintenance work orders based on the determination;

determining a plurality of constraints associated with performing maintenance on the plurality of components; and

generating the maintenance schedule for the plurality of components based on the time-based maintenance information, the condition-based maintenance information, and the plurality of constraints.