Patent Grant
7440906
This application is related to application Ser. No. 09/946,093, entitled “Maintenance, Repair And Overhaul Management,” and application Ser. No. 09/946,032, entitled “Planning, Scheduling, Allocation of MRO Resources,” both of which were filed on Sep. 4, 2001 and commonly assigned to the assignee of the present application.
This application relates generally to managing maintenance of equipment. More particularly, this invention relates to identification, categorization, and integration of unplanned maintenance repair and overhaul (MRO) work in an MRO business organization.
A number of businesses focus their operations on the maintenance, repair or overhaul of complex equipment. Aircraft fleet and truck fleet maintenance are two commonly known businesses in this arena. In addition other business that have to maintain expensive complex machinery and other capital equipment such as fully automated manufacturing plants also require the maintenance, repair and/or overhaul of their equipment to keep the business operations running profitably.
Historically, within MRO business organizations, resource planning has been performed as a product of resource availability within a very near term time window, usually within weeks. The specific scheduling activity of MRO tasks usually is the product of responding to emergencies and matters of necessities to keep a particular end item, or a piece of equipment, in service. The result is that maintenance schedules often serve as general guidelines with critical resources being poorly allocated. Those resources typically need to be continually swapped and reallocated in an ad hoc manner to meet the emergency maintenance needs. This informality often results in both excessive equipment down times and excessive cost of maintenance.
Scheduling systems have been developed to permit the performance of MRO tasks to a predefined schedule and support that schedule with the correct components, raw materials, information, skilled or certified personnel, tooling and facilities. The ability to reliably schedule MRO work is important to an MRO business and its customers. The predictability of schedule performance is one of the most difficult issues facing MRO management. Such predictability is the foundation of both financial and technical success for an MRO business.
In the MRO environment, and especially while performing maintenance on more technically complex end items, the discovery of unplanned work (also known as “above and beyond”, or “emergent” work) during the execution of the original maintenance plan is problematic. Such unplanned maintenance work increases the level of difficulty of the effort, makes the supporting of the original plan much less efficient, and can create chaos within the work schedule. Of all of the tasks which must be performed once an item of unplanned work is discovered, the actual identification and categorization of the work content for that unplanned item is one of the most crucial factors in successfully dealing with the unplanned work and the schedule.
Historically, the identification and categorization of such unplanned work has been manual in nature, open to great latitude in description (both as to accuracy and detail of the description), and time consuming for the mechanic or technician. Additionally, the time spent performing the essentially clerical task of identifying and categorizing the work is time lost from the execution of the already planned maintenance. This is a source of inefficiency and wasted resources.
In those industries subject to extensive government regulation, the degree of detail required in the description of such tasks compounds the problem further. For example, commercial and military aircraft MRO operations must be scheduled and logged in accordance with government requirements. Disruptions to the schedule must also be logged and accounted. Manual records must be maintained for subsequent verification by regulators. The processing of these manual records, the reaction of the full business to the content of those records (purchasing of components; assignments of personnel; etc.), and the degree of human error represented by those records has made them a serious roadblock to the improvement of the MRO businesses.
Further difficulty occurs when attempts are made to integrate newly identified and categorized work with a pre-existing maintenance plan. This difficulty arises in reference to the placement and sequencing of the discovered work within the pre-existing plan. This difficulty also arises in reference to the availability of the required components, information, tooling, and certified personnel to perform the tasks. A general rule of thumb is that over 50% of the tasks accomplished by an MRO activity were not part of the original workplan, and well over 60% of the time required to perform the tasks (and the cost associated with the maintenance business) are originally unplanned, meaning discovered during planned work execution.
Accordingly, there is a need for improved methods and apparatus for identification, categorization and integration of unplanned MRO work in a schedule of planned work.
By way of introduction only, the present invention provides in one embodiment a method for managing maintenance of equipment. The method includes identifying a planned MRO task and a first set of components associated with the task and determining a set of probabilities associated with a second set of components and indicating that the second set of components will require maintenance during the planned MRO task. The method further includes developing a plan for maintenance of individual items in the second set of components and, upon discovering a need for maintenance of at least one item of the second set of components, accessing the plan and integrating it with a plan of planned MRO tasks for the equipment.
In another embodiment, the invention further provides a method for managing maintenance of equipment. The method includes discovering a component of the equipment requiring unplanned maintenance and identifying a location of the component. The method further includes identifying a category of work required for the unplanned maintenance, identifying a task description in the category of work to be performed, identifying a data code on the component, obtaining information from one or more databases associated with maintenance of said equipment, and scheduling the unplanned maintenance into a schedule of planned maintenance based on the information obtained from the one or more databases.
In yet another embodiment, the invention further provides a system for managing the maintenance of equipment by integrating planned maintenance with unplanned maintenance. The system includes a network user interface in communication with a network and at least one storage device in communication with the network, the storage device being configured to store data from a plurality of databases. These databases in one embodiment include a Planned Work Probable Findings database including data of probability that, during planned maintenance of a first component, a second component will be identified as requiring unplanned maintenance, a Geography Definition database including data defining physical zones within which a repair task may be performed on a piece of equipment, a Planned Work Geography Locator database including data associating a planned MRO task to a physical zone, and a Component Tracking database including data selected from one or more of part numbers, component serial numbers and tracking numbers, the Component Tracking database being linked to a configuration database; and a scheduler for scheduling maintenance for a plurality of maintenance time periods; wherein the network user interface is configured to provide access to data from one or more database to describe a MRO task for a component of the equipment discovered to require maintenance; and wherein said scheduler includes logic to integrate the maintenance of the second component into a maintenance plan for said maintenance in a selected time period.
In yet another embodiment, the invention further provides a method for managing maintenance of equipment. The method includes identifying a planned MRO task of the equipment and based on location of the planned MRO task, retrieving from a memory probable MRO tasks associated with the planned MRO task.
In yet another embodiment, the invention further provides a computer readable equipment maintenance database storage medium. The storage medium includes first data defining planned maintenance items for equipment and second data defining probable maintenance items for the equipment. The second data is associated with the first data by geographic data for the equipment.
In yet another embodiment, the invention further provides a method for forming an equipment maintenance database. The method includes identifying a planned MRO task for equipment and identifying one or more geographical areas of the equipment associated with completion of the planned MRO task. The method further includes determining unplanned MRO tasks associated with the one or more geographical areas and, in a database, storing first data related to the planned MRO task, storing second data related to the unplanned MRO tasks, and associating the first data and the second data by data related to the one or more geographical areas of the equipment.
The foregoing summary has been provided only by way of introduction. Nothing in this section should be taken as a limitation on the following claims, which define the scope of the invention.
Referring now to the drawing,
A component is not limited to mechanical elements and is broadly defined to include an electrical assembly, an electrical system, an electronic system, a computer controller, software, hydraulics, plumbing, and the like. Mechanical equipment includes heavy equipment and capital intensive equipment that is movable or fixed. Mobile mechanical equipment includes airplanes, buses, locomotives, ships, cranes, heavy trucks, earth moving equipment, and the like. Fixed mechanical equipment includes electrical power generators, industrial presses, manufacturing equipment or the like.
The system 100 forms a system for managing the maintenance of equipment by integrating planned maintenance of the equipment with unplanned maintenance for the equipment. In one exemplary embodiment described herein, the system 100 may be used in conjunction with a maintenance, repair and overhaul (MRO) system for performing MRO work on equipment. In another exemplary embodiment, the system 100 is used by a provider of MRO services for airplanes such as military and commercial airplanes. However, the system is not so limited and may be used in conjunction with any type of equipment or system.
The system 100 includes a computer network 102, a user interface 104, a server 106, a storage device 108 and a scheduler 110. The network 102 may be any suitable data communications network, such as a local area network, wireless network, etc. Many networking standards have been developed and may be adapted for application as shown in
The user interface 104 is in communication with the network 102 and provides access to data and applications located remotely on the network 102. In the illustrative embodiment, the user interface 104 is embodied as a personal computer. In other embodiments, different types of data entry and data communication devices may be used. For example, in one alternative embodiment shown in
The server 106 provides a process workflow and messaging device for the system 100. The server 106 is in communication with the user interface 104, the storage device 108 and the scheduler 110. The server 106 may also provide data communication with other devices, such as other networks.
The storage device 108 is in communication with other components of the network 102. The storage device is configured to store data in a plurality of databases. These databases include a planned work probable findings database 116, a planned work geography located database 118, a work description library 120, a geography definition database 122, a standard repair library 124, a standard parts list 126, a component part and serial number database 128, configuration databases 130 and possibly other databases 132. The other databases 132 may store ancillary information such as data and applications for use by components such as the server 106 and the user interface 104 of the network. The content and creation of these databases along with their use for scheduling planned and unplanned MRO work will be described in more detail below.
MRO work is organized by task. Examples of aircraft MRO tasks are “overhaul engine number 1,” or “inspect brake pads on nose landing gear.” Many MRO tasks are planned and scheduled according to a regular preventative maintenance schedule or other planning basis. For each planned MRO task, an analysis is performed to determine what types of additional, unplanned MRO work may be found during routine maintenance within the same geographical area of the equipment. Relative probabilities are assigned to those possible work events and the planned work probable findings database 116 is established from that analysis. One example of data organized in a planned work probable findings database is shown in
Defined categories of MRO work, such as mechanical, electrical, software, etc. are specified along with expected types of tasks relative to that category. For example, plumbing could be expected to have leaks of varying severity, including seepage, pooling, heavy volume, burst pipe, etc. As another example, structural failures could include task types such as corrosion, cracking, fastener loss and bending, etc. For each of these categories and tasks types, standard nomenclature is developed and category/task-type pairs are established. The resulting data is stored in the work description library database 120.
For each unplanned work category/task type pair identified in the work description library database 120, a standard method of repair is established and associated data is stored in the standard repair library database 124. This library, in one embodiment, includes task descriptions, basic required tool listings as well as any special processing notes, skills or certifications required for the task, including safety warnings. This database also includes both schedule span estimates and cost estimates of the effort required to accomplish the standard repair tasks.
For each entry in the standard repair library database 124, a generalized components list of the items forecast to be required to be perform a specified maintenance or repair task is established in the standard repair parts list library database 126. This database may be organized by part numbers or nomenclature or both. In case of a database organized according to nomenclature only, various analysis techniques related to the context of the semantics used to describe the components may be applied to determined proper part applications for the various configurations.
The equipment geography description database 122 stores data related to geographic zones or locations for all maintained areas of the end item of equipment. This may include detailed information about subareas, focused on defining where maintenance work has been located on the end item of equipment. For example, geography must be specified as “right-hand front fender—rear edge” or “left-hand forward wheel well—pump mount side.” Only those areas determined to be subject to frequent or expensive maintenance may be listed. Preferably, the geographic location descriptions are related to a user graphical interface allowing for rapid point-and-click data acquisition. That is, a user operating a pointer-type device in conjunction with a display device may find and identify a specific geographic location or zone quickly using a graphical user interface. In instances where industry regulatory entities have pre-established geographic areas or zones or sub-zones, such as the ATA zones specified by the Air Transport Association for commercial aircraft, utilization or cross references may made to those standards in the geographic description database 122. An example of the ATA zones is provided herein as an appendix.
The component part/serial number database 128 stores part numbers or component serial numbers or some other unique tracking number for components of the equipment. The configuration database 130 stores information about the configuration or interrelationship of the components and parts of the equipment. These databases may be accessed for additional information about equipment needing repair or replacement.
While the several databases shown in
The scheduler 110 schedules maintenance for a plurality of maintenance time periods for equipment as part of the operation of the MRO system. As noted above, some MRO work occurs according to a schedule, such as routine preventative maintenance or overhaul work. Some MRO work may be planned but unscheduled, such as repairs. The scheduler 110 tracks work that must be performed over time against a calendar and using information about availability of other resources.
The scheduler 110 is illustrated in
The scheduler receives data inputs regarding equipment on which maintenance is to be performed, the maintenance to be performed on the equipment, and resources available to perform the maintenance, such as parts and personnel. The scheduler may also receive other information such as availability of the equipment and planned maintenance schedules for the equipment. Using this information and other required information, the scheduler 110 develops a maintenance plan for maintenance in a selected time period for specified equipment. As will be described in greater detail herein, the scheduler 110 further receives information about unplanned work identified, for example, by a technician during inspection or performance of other work. The scheduler 110 integrates performance of the unplanned maintenance work into the maintenance plan for the equipment.
It is to be noted that other embodiments of the system 100 may be substituted. The functionality provided by the system may be alternately provided by computation and data storage devices having any configuration which is suitable to the needs and purposes described herein. The configuration shown in
At block 202, unplanned MRO work is discovered. This may occur at any point in the MRO work process. For example, the unplanned work may be discovered before the equipment is delivered for MRO processing. The MRO work may be discovered while planned MRO work is under way, for example, when the equipment has been opened up for access to a planned work area.
In accordance with one embodiment, for each item of unplanned work discovered, an MRO technician or mechanic utilizes a computer input device to define the location of the work on the equipment. Two techniques for location definition are envisioned, and others may be implemented as well. In one technique, the location of the unplanned work is specified using the most relevant planned work definition, as specified in the probable findings database 116 (
Preferably, the location definition operation described by block 204 occurs when the technician clicks on an item on a menu. The menu may be presented to the technician by means of the user interface 104 or a device such as the wireless data communication device 112 in communication with the user interface 104. It is envisioned that the user interface will provide an easy to navigate menu system for data entry and access by a technician, mechanic or other operator. The menus are preferably dynamic pop up or pull down menus, with menu selections varying with the context of the menu. Only appropriate menu choices are provided to the user depending on his current context or location in the menu system or level of operation.
At block 206, the operator specifies the geography/work pairing for the unplanned work items. Preferably, this is accomplished using a point and click menu system associated with a user interface. The menu system may be used to access or specify the particular geographical location of the equipment. The menu system may further be used to select or identify a particular item of unplanned MRO work to be completed at the specified geographical location. This task description selection is preferably based on a pull down menu of relevant information only, and a click-to-verify method for input. That is, once the geographical location has been identified by the operator, only the possible work tasks in that geographical location are made available by the menu system. If the operator specifies an area of the assembly where only hydraulic systems are located, only hydraulic work tasks will be displayed by the menu system. Other tasks, such as electrical tasks and airframes repair tasks, will be suppressed.
At block 208, the operator identifies and verifies the work category for the items of unplanned work. Preferably, different tasks are specified in different categories of work. For example, in the airplane repair context, categorization may assign tasks to categories such as hydraulics, electrical, airframe repair, etc. Categorization can be important to allow allocation of proper and necessary resources for completion of the planned and unplanned work. Alternatively, the tasks could be categorized by geography, specifying physical regions of the equipment under repair for categories to which work tasks may be assigned.
At block 210, a task description for the unplanned work tasks is identified and verified. Again, this is preferably accomplished using a pull down menu of relevant information, along with a click-to-verify method for input. Based on the information provided by the technician, the system responds with a pull down menu whose entries are limited to only relevant or proper entries. Irrelevant or improper entries are suppressed.
At block 212, component data is acquired by the system. In one embodiment, this is done by reading a data code from the device. The data code may be machine readable, such as a bar code or magnetic stripe or may be a part number or serial number attached to the device. The data code is a unique identifier of the device. In another embodiment, this is done by posing tailored questions to the operator to obtain the required information. The questions may be posed using a video entry device associated with the user interface of the system or with the wearable communication device. Alternatively, an audio interface may be provided. The questions are tailored to the type of MRO task already identified by the technician. In one example, the following questions may be transmitted to the operator for data entry.
At this point, the answers to the tailored questions along with other data entered by the operator have provided the system with sufficient information to draw inferences as to the next steps required. Any appropriate or available application may be employed to perform necessary logical operations to process the input information. The system can accordingly initiate required transactions in support of those next steps.
The information provided by the operator and obtained from the storage device of the system allows the system to fully identify and describe the unplanned work task. At block 214, the system establishes an unplanned task data record, which may be located in a portion of memory for storing data related to the unplanned task. At block 216, the system determines a time span/cost estimate for the unplanned task. The time and cost estimates may be based on prior art data or experience performing similar unplanned work. At block 218, the system orders the necessary support for the task. Examples of required support include components for repair and replacement, information such as directions, and personnel.
At block 220, the unplanned work is sequenced into the planned work sequence to produce a revised work plan. This forms the preparation of an integrated schedule including the original work tasks and the newly discovered tasks. After producing the revised work plan, the method illustrated in
It may happen that the system cannot develop the necessary described linkages. In that case, a transaction is produced by the system to a maintenance control area for further analysis or engineering assistance. In all cases, the unplanned work is fully identified, categorized and integrated to the total work plan prior to executing the repair task. This reduces or eliminates the uncertainty and variability formerly associated with unplanned MRO work.
In the embodiment illustrated in
Linking the planned MRO tasks and the probable maintenance items is location data. The location data defines the physical or geographical location of the equipment where the components associated with the planned maintenance and probable maintenance may be found. The location for respective probable maintenance items associated with a common planned MRO task may vary. A location pointer 316 points to the currently accessed location in the database. Thus, this database may be considered a two-sided database.
Two-way operation of the database 116 may occur as follows. The database may be accessed using any suitable database management system or other user interface. Preferably, in the embodiment of
It should be noted that there may be several different location entries which may be associated with a single planned MRO task 302, 304, 306. For example, in the airplane context, if the planned MRO task 302 is described as “inspect air conditioning air ducts,” such ducts run the length of the plane, in a plurality of locations. Each separate location may have a separate probable MRO task 312, 312, 314 associated therewith.
The planned work geography locator database 116 can be formed in any suitable method. In one embodiment, this database is formed by identifying a planned MRO task for particular equipment and identifying one or more geographical areas of the equipment associated with completion of the planned MRO task. Subsequently, unplanned MRO tasks are identified which are associated with the one or more geographical areas. For example, a planned MRO task may be identified as “inspect left wing hydraulic lines.” The geographical areas for the airplane associated with this MRO task may be identified as the left wing and individual components and spaces thereof. An example of unplanned MRO tasks associated with the one or more geographical areas is “left wing airframe damage” or “worn electrical cables in left wing.”
The method for forming the equipment maintenance database further includes storing in a database first data related to the planned MRO task. This data may define, for example, an element or component requiring maintenance and the particular maintenance to be performed. The method further includes storing second data in the database, the second data related to the unplanned MRO tasks which have been identified for the geographical areas associated with the planned MRO task. The method still further includes associating the first data and second data by geographic data related to one or more geographical areas of the equipment. In one example, the geographical data may be data related to the codes established by the Air Transport Association industry organization to define an standard reference characteristic the geographical locations of an airplane. Examples of these codes are included herewith as an Appendix.
At block 416, the operator is prompted to enter a required time for completion of the unplanned MRO task. A response is received at block 418. In addition, in one embodiment, external data is also received related to timing and duration of maintenance work. In one example, some airlines specify a very short turnaround time, meaning the duration from arrival of an airplane at an airport gate until subsequent departure of the plane on a next flight from the gate. Some airlines specify a turnaround time of 20 minutes. Other airlines specify a turnaround time of, for example, one hour. This information may be used, in conjunction with the data entered at block 418 to schedule the unplanned maintenance. Thus, if the data entered requires less than one hour for completion, and the turnaround time received at block 420 is an hour or more, the system may conclude that this unplanned work item may be completed during a turnaround process, assuming personnel and the equipment required for the task are available.
At block 422 the operator is prompted for a need for evaluation of the completed work. A response is received at block 424. At block 426, the operator is asked if an engineer is required for completion of the task. A response is received at block 428. At block 430, the operator is asked if quality assurance personnel are required for completion of the work item. A response is received at block 432. At block 434, the operator is asked if a lead technician or mechanic is required for completion of the task. A response is received at block 436.
Other questions may be asked of the operator based on the location and nature of the unplanned work to be performed and based on other information provided in the responses to the questions. The questions may be viewed as a tree, where the branch taken in the tree by the system is dependent upon the input received from the operator. Any number of questions may be generated depending upon the responses provided by the operator. Preferably, the number of questions is limited to the range of six to ten questions which are fairly general in nature for ready response by the operator.
From the foregoing, it can be seen that the present invention provides method and apparatus for identification, categorization and integration of unplanned MRO work in an MRO work schedule. A technician identifies location of the unplanned work and answers tailored questions posed by the system to obtain additional information about the nature of the work. Using this information, the system identifies and describes the unplanned work tasks and modifies the schedule for planned maintenance work to include the identified unplanned work. In this manner, the required components, information, tooling and personnel to perform the tasks, both unplanned and planned tasks, may be scheduled for efficient utilization and completion of the work schedule.
While a particular embodiment of the present invention has been shown and described, modifications may be made. It is therefore intended in the appended claims to cover such changes and modifications which follow in the true spirit and scope of the invention.
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