Note: Descriptions are shown in the official language in which they were submitted.
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PERFORMING PREDICTIVE MAINTENANCE BASED ON A PREDICTIVE
MAINTENANCE TARGET
FIELD OF THE INVENTION
This invention relates to a method and system for performing predictive
maintenance on an item of equipment based upon a predictive maintenance
target, (e.g.,
an objective or a configuration for the equipment).
BACKGROUND OF THE INVENTION
The performance of predictive maintenance may be based upon maintaining
reliability or availability of an item of equipment for operational use. A
predictive
maintenance plan (e.g., a maintenance, repair and overhaul (MRO) plan) may
include
replacing or repairing one or more components at various times to minimize the
downtime of the equipment. The decision of what components to replace or
repair and
when to replace components may be based upon a factor that relates to the
physical
condition of a component, an estimated physical condition of a component, or
other
similar factors. Accordingly, although a component of the equipment may comply
with a
desired physical condition, the overall performance of the equipment may not
satisfy a
desired performance standard. Thus, a need exists for performing predictive
maintenance
that considers one or more other factors beyond the observed physical
condition of a
component.
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Even if the reliability of the equipment may be maintained in accordance with
a
limited predictive maintenance scheme, restricted to the physical condition of
a
component, the limited predictive maintenance scheme may be economically
inefficient
for a maintenance service provider. For example, the maintenance provider may
suffer
reduced economies of scale by purchasing duplicative and interchangeable
components.
Further, the maintenance provider and the equipment operator may incur
additional
expenses by poor timing of maintenance activities based on an insufficiently
robust
prediction of equipment reliability or of the useful service life of
respective components.
Thus, a need exists for managing the interchangeability, repair, or
replacement of
components in a predictive maintenance environment.
Another feature that a prior art predictive maintenance scheme may lack is a
framework to support the decision of whether to repair a component or an
assembly of
components, rather than replace the component or assembly of components with
another
component. For example, the equipment may have additional downtime if an
inappropriate decision is made to repair or refurbish a critical component,
rather than
providing a new component. Thus, a need exists for a predictive maintenance
scheme
that supports an enhanced maintenance decision on: (1) whether to repair or
replace
components (e.g., parts) of an item of equipment and (2) the determination of
a suitable
schedule (e.g., the most advantageous schedule) for the execution of the
maintenance
decision.
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SUMMARY OF THE INVENTION
In accordance with the invention, the method for performing predictive
maintenance on an item of equipment comprises establishing a desired
configuration of
the item of equipment based on a predictive maintenance target of the item of
equipment.
The predictive maintenance target may include at least one of a physical
configuration
objective, a functional configuration objective, a logical configuration
objective, and an
operational configuration objective. An actual configuration of the item of
equipment is
monitored. It is determined if the actual configuration complies with the
desired
configuration. An upgrade requirement is planned for upgrading the actual
configuration
to the desired configuration if the actual configuration is non-compliant.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a block diagram of a predictive maintenance system in accordance
with
the invention.
FIG. 2 is a block diagram which shows an illustrative example of the data
processor of FIG. I in greater detail.
FIG. 3 is a flow chart of a method for performing predictive maintenance in
accordance with the invention.
DETAILED DESCRIPTION OF THE INVENTION
As used herein, a maintenance provider shall include any person or business
entity that performs or supports maintenance, repair, or overhaul activity
(i.e., an MRO
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activity) for at least one item of equipment. Similarly, maintenance, a
maintenance
activity or a maintenance task shall include at least one of maintenance,
repair, and
overhaul (i.e., MRO) of an item of equipment or a component of the equipment.
A component means a component of an item of equipment, a sub-component of
an item of equipment, an assembly of an item of equipment, a system of an item
of
equipment, or any other constituent component of an item of equipment. A
component
may include, but need not include, one or more sub-components. An assembly may
comprise a group of integrated or inter-related components. A material refers
to a raw
material, a consumable material, a component, a provision, or another
equipment-related
resource concerning the performance of a maintenance activity.
In accordance with the invention, FIG. 1 shows a block diagram of a predictive
maintenance system 11 in accordance with the invention. The predictive
maintenance
system 11 is adapted to manage a configuration of mechanical equipment. A
maintenance inpudoutput device 10, an engineering input/output device 12, and
a
supervisory input/output device 14 are coupled to a data processing system 16
to permit
the input of data into the data processing system 16. The data processing
system 16 may
be coupled to a materials management system 36 to permit the output of data to
the
materials management system 36. Further, the data processing system 16 may be
coupled to maintenance management system 42 to provide data for operation of
the
maintenance management system 42.
The data processing system 16 includes a storage device 20 coupled to a data
processor 30 and communications interfaces 18 coupled to the data processor 30
via a
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databus 34. The databus 34 and communications interfaces 18 provide access of
the
input/output devices (10, 12 and 14) to one or more databases (22, 24, 26 and
28). The
arrows interconnecting the components of the data processing system 16
represent data
flow over the databus 34. Although only one databus is shown in FIG. 1, in
other
embodiments multiple databuses and/or multi-processor computer architecture
may be
used to practice the invention.
The storage device 20 refers to any data storage mechanism that supports a
magnetic storage medium, an optical storage medium, an electronic storage
medium, or
any other suitable storage medium. The storage device 20 may contain an actual
configuration database 22, a desired configuration database 24, a upgrade
requirements
database 26, and a supervisory/ historical database 28. The data processing
system 16
supports data storage, retrieval, and queries of the databases stored in the
storage device
20.
The maintenance input/output device 10 is coupled to the actual configuration
database 22 via a communications interface 18. The engineering input/output
device 12
is coupled to the desired configuration database 24 via a communications
interface 18.
The supervisory input/output device 14 is coupled to the supervisory database
28 via a
communications interface 18. In one embodiment, the maintenance input/output
device
10, the engineering input/output device 12, and the supervisory input/output
device 14
may represent computer work stations or other data input/output devices. In
another
embodiment, the maintenance input/output device 10 may comprise a monitor for
manually or automatically monitoring the operational performance or longevity
(e.g.,
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time and/or operational cycle compliance) of a component (e.g., a part), an
assembly, or
the entire mechanical equipment. For example, the monitor may provide a report
of
assembly longevity data or component longevity data for storage in the actual
configuration database 22.
The actual configuration database 22 and the desired configuration database 24
provide input configuration data to the data processor 30. The data processor
30 outputs
upgrade requirements data to the upgrade requirements database 26 and the
supervisory
database 28 based on the input of the configuration data. The supervisory
database 28
may include historical configuration data on previous configurations and
associated
performance of previous configurations of the mechanical equipment. The
upgrade
requirements database 26 is coupled to an output communications interface 32.
The communications interfaces 18 may comprise buffer memory coupled to
transceivers. The communications interfaces 18 may support a parallel port, a
serial port,
or another computer port configuration.
The output communications interface 32 may comprise buffer 38 memory
coupled to a transceiver 40. The output communications interface 32 is adapted
to
transmit upgrade requirements data, maintenance plan data, or revision data
from the
upgrade requirements database 26 to one or more of the following devices: (1)
the
materials management system 36 (e.g., purchasing system), (2) maintenance
management
system 42, and any other procurement or enterprise resource planning system.
For
example, the output communications interface 32 may contain a software
interface, a
hardware interface, or both to facilitate the proper exchange of information
with the
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materials management system 36, the maintenance management system 42, a
purchasing
system, or an enterprise resource planning system.
The desired configuration database 24 contains desired configuration data on
the
mechanical equipment. The desired configuration data contains an equipment
identifier
(e.g., tail number of an airplane) that identifies the entire mechanical
equipment, a part
identifier or component identifier that identifies a component of the
mechanical
equipment, an assembly identifier that identifies an assembly of components of
the
equipment, a specification description that describes the specification of a
component,
and a relationship description that describes the relationship of a component
to the
mechanical equipment or a subassembly thereof. For example, the relationship
description may include the mounting position of a component on the mechanical
equipment. In one embodiment, the desired configuration database 24 may
include
operating restrictions on the mechanical equipment because of the presence of
a
particular component or a particular arrangement of components of the
mechanical
equipment.
The desired configuration may include at least one of a physical configuration
objective, a logical configuration objective, a functional configuration
objective, an
operational configuration objective, a redundant configuration objective, and
a self
healing configuration objective. A physical configuration defines or
identifies one or
more of the following: components, subcomponents, a system, and an assembly
for a
complete, operational item of equipment. A logical configuration defines the
interrelationships among components, sub-components, a system, an assembly, or
other
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components of equipment. A functional configuration defines what technical
specifications (e.g., performance specifications) the item of equipment is
expected or
desired to meet. An operational configuration defines the operational
performance of a
particular item of equipment, with respect to the particular item as a whole,
or any of its
constituent parts, including components, subcomponents, assemblies, and
systems. A
redundant configuration may include duplicate measures or secondary
components,
systems, or assemblies that take over upon the failure of primary component,
system or
assembly. A self healing configuration may include architecture that is fault
tolerant
with respect to redundant software, redundant hardware, or other technical
enhancements.
The actual configuration database 22 contains actual configuration data on the
mechanical equipment that reflects an actual or present status of the
mechanical
equipment. The actual configuration data may include any of the following
types of data:
an equipment identifier that identifies the entire mechanical equipment (e.g.,
by class,
type, or otherwise), a unique identifier (e.g., a serial number or a tail
number of an
airplane) that distinguishes a particular item of equipment from other items
(e.g., all other
items) of equipment, a component identifier (e.g., a part identifier) that
identifies a
component (e.g., a part) of the mechanical equipment, an assembly identifier
that
identifies an assembly or group of components of the equipment, a
specification
description that describes the specification of the component, and a
relationship
description that describes the relationship of a component to the mechanical
equipment or
a subassembly thereof. For example, the relationship description may include
the
mounting position of a component (e.g., a part) on the mechanical equipment.
In one
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embodiment, the actual configuration database 22 may include operating
restrictions on
the mechanical equipment because of the presence of a particular component or
arrangement of particular component on the mechanical equipment.
The contents of the actual configuration database 22, the desired
configuration
database 24, and the upgrade requirements database 26 may vary with time.
Accordingly, configuration data on a particular mechanical equipment may only
remain
valid for a limited duration. Upon or before expiration of the duration, the
configuration
is preferably updated. If the contents of the databases are updated with
sufficient
frequency to avoid outdated configuration data, the update procedure may be
referred to
as a real-time procedure. The real-time procedure seeks to minimize inaccuracy
of the
configuration data by reflecting changes to the actual configuration of the
mechanical
equipment as. the changes occur with a minimal lag time thereafter. Changes to
the actual
mechanical equipment may be necessary or proper to facilitate improvement of
the actual
configuration. Thus, the data processing system 16 permits maintenance
activities (e.g.,
maintenance, repair or overhaul) to be coordinated in real time on an ongoing
basis with
the latest actual configuration data and the latest upgrade requirements.
The actual configuration may be defined by one or more of the following:
observed physical configuration data, observed functional configuration data,
an
observed logical configuration data, and observed operational configuration
data. The
desired configuration may be expressed in terms of one or more of the
following
configuration objectives: a physical configuration objective, a functional
configuration
objective, a logical configuration objective, and an operational configuration
objective.
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The observed physical configuration data and the physical configuration
objective
are collectively referred to as physical configuration data. The observed
functional
configuration data and functional configuration objective are collectively
referred to as
functional configuration data. The observed logical configuration data and the
logical
configuration objective are collectively referred to as,logical configuration
data. The
observed operational configuration data and the operational configuration
objective are
collectively referred to as operational configuration data.
The physical configuration data may generally include one or more of the
following: component identifiers, sub-component identifiers, assembly
identifiers, and
system identifiers, along with data associated with a particular item
identifier or
equipment identifier. The item identifier or equipment identifier may be a
serial number.
For example, where the equipment is an aircraft, the equipment number may be
regarded
as a tail number. The item number or equipment number provides a unique
identification
for the particular item of equipment to distinguish that particular item from
other items
(e.g., similar items) of equipment . A physical configuration may refer to a
specific
instance of a logical configuration, data of the physical configuration is
with reference to
a particular end item.
Functional configuration data may describe the specifications, such as
technical
specifications for the equipment. The functional configuration data may define
the
configuration in terms of what the operational limitations, functional
specifications or
capabilities of the equipment are or are expected to be. For example, the
functional
configuration may describe the operating capacity of the end item of the
equipment.
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The logical configuration data may define components or the interrelationship
between components or assemblies or systems. The logical configuration data
may
describe interrelationships and organization of the constituent members of the
item of
equipment.
The operational configuration data may take into account the usage and
performance of the equipment in an operational environment. The operational
configuration data may include the operational data on one or more of the
following:
number of cycles of a system of the equipment, a number of hours of usage,
another
usage measurement data associated with the particular item or the particular
equipment.
Operational configuration data may be gathered by a sensor or a person
associated with
the equipment, by a system of the equipment, by a component of the equipment
or
otherwise. The operational configuration may define the number of cycles or
the
operational history that a particular physical configuration has progressed
through during
its lifetime. The operational configuration may also define how the end item
has been
performing after the replacement of a particular component or a particular
assembly in
the end item.
In one example, a maintenance worker, such as a technician or a mechanic who
is
responsible for maintaining or repairing the mechanical equipment, enters
actual
configuration data (e.g., observed configuration data) into the actual
configuration
database 22 during or after an inspection or servicing of the mechanical
equipment. The
inspection may involve a visual inspection, a physical inspection, a
mechanical test, an
electrical test, disassembly of portions of the mechanical equipment, or other
activities
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that might uncover defects or nonconformities with respect to the desired
configuration.
The data processing system 16 updates the actual configuration data in the
actual
co~guration database 22 as soon as possible after the inspection or the
servicing of the
mechanical equipment to maintain the accuracy of the actual configuration
database 22.
For example, the maintenance input/output device 10 may be a portable
electronic device
that is equipped to establish a wireless communications link or otherv~iise
communicate
with the data processing system 16.
The data processor 30 compares the actual configuration to the desired
configuration. The difference between the actual configuration and the desired
configuration may be referred to as the upgrade requirement. The upgrade
requirement
or revision defines the departure of the actual configuration from the desired
configuration and indicates the necessary actions to bring the mechanical
equipment into
conformity with the desired configuration. The data processor 30 determines
the upgrade
requirement. The data processor 30 may express the upgrade requirement in
terms of (1)
a component requirement (e.g., part, assembly or subassembly requirement) and
(2) a
human resource requirement that is required to bring the actual configuration
in
conformity with the desired configuration. The upgrade requirements may
contain
component identifiers of old components that require updating of a particular
mechanical
equipment to gain compliance with the desired configuration. The component
requirement is not limited to electrical or mechanical hardware. For example,
the
component requirement may include modifications of software features and
software
instructions that are associated with or integral to the functioning of the
mechanical
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equipment. The human resource requirement may include the scheduling of one or
more
maintenance workers (e.g., technicians and mechanics) to install, repair,
adjust,
reconfigure, replace or otherwise perform a service associated with the
component
requirement for the mechanical equipment.
The data processor 30 may define an interim solution to eliminate potential
delay
in the execution of a complete upgrade to the mechanical equipment. For
example, the
interim solution may reduce or eliminate the delay for an upgrade, where
requisite
components are not immediately available or qualified service personnel are
not available
for a complex service procedure. The interim solution covers the time period
after a
noncompliance with the desired configuration is detected and prior to placing
the actual
configuration in conformity with the desired configuration. The interim
solution may
define time/operational limitations or restrictions for the mechanical
equipment prior
bringing the discrepant component of the mechanical equipment into conformity.
The
interim solution may entail restricted usage of the non-conforming equipment.
Further,
the human resources requirement may include provisional operational training
to properly
operate the mechanical equipment under the time/operational limitations or
restrictions.
The component requirements (e.g., part requirements) are forwarded over the
output communications interface 32 to the materials management system 36 or
another
computer system that supports acquisition of components for the mechanical
equipment.
The materials management system 36 is a computer system for obtaining
components for
the mechanical equipment from a supplier or obtaining components from existing
internal
sources (e.g., a parts depot , warehouse, internal manufacturing source, or
the like). The
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component requirements may include a quantity, a description, a manufacturer's
equivalent component (e.g., part) number, or other component (e.g., part)
parameters.
With respect to mechanical equipment that has a software component, the
component
requirements may include version or revision information or any other
parameter
necessary to provide the upgrade of the software configuration associated with
the
mechanical equipment.
In an alternative embodiment, the components requirements are forwarded over
to
an enterprise resource planning system, rather than the materials management
system 36.
An enterprise resource planning system is a computer system that facilitates
the exchange
of information between different operational or business systems of a business
entity.
For example, an enterprise resource planning system may facilitate the
exchange of
information between purchasing, engineering, manufacturing, and management
systems
of a corporation.
In general, the supervisory database 28 supports management's oversight of the
managing of the configuration. Additionally, the supervisory database 28
retains the
historical records of prior configuration alterations. The supervisory
database 28 tracks
historic configurations of the mechanical equipment and any associated failure
or defect
with historic configurations. A description of the failure or defect, a date
of detection of
the failure of defect, determined causal factors from failure analysis
activities, and
resolution or repair of the failure or defect are preferably noted in the
supervisory
database 28. The foregoing failure or defect data may supplement or be used to
update
mean-time-between failure (MTBF) data provided by the manufacturer on
components or
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assemblies of the equipment. In turn, the updated MTBF may be used to change
the
desired configuration with input from engineering over the engineering
input/output
device 12.
The supervisory database 28 may record approvals of engineering changes to the
desired configuration database 24. In addition, the supervisory database 28
may record
and archive approvals of work, past configurations, or inspections by
maintenance staff.
Thus, the supervisory database 28 promotes accountability of mechanics,
technicians,
engineers, and management for activities related to managing the
configuration. This
supervisory database 28 may represent a repository of historical records,
including
satisfaction records of executed configuration changes for the purpose of
regulatory
compliance, safety compliance, or otherwise.
The planning module 110 supports decisions on whether to repair or replace a
particular component of an item of equipment. The decision to repair or
replace may be
based upon economic data, on the cost of replacement versus the cost of
repair, reliability
of a repaired component versus a replaced component, shipment and ordering
time for a
new component, whether a new component is in inventory, repair time for
repairing the
component or other factors. The planning module 110 may consider one or more
of the
foregoing factors to determine whether or not to replace or repair a
component. The
supervisory management input/output device 14 may have the ability to override
such a
decision to repair or replace a component. Similarly, the engineering
inputloutput device
12 may be given authority to override such a decision.
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FIG. 2 shows the data processor 30 of FIG. 1 in greater detail. The data
processor
30 of FIG. 2 includes a configuration manager 100 and a configuration monitor
104
coupled to an evaluation module 108. In turn, the evaluation module 108 is
coupled to a
planning module 110. The desired configuration database 24 provides desired
configuration data as input to the configuration manager 100. The actual
configuration
database 22 provides actual configuration data as input to the configuration
monitor 104.
The output of the planning module 110 is coupled to an upgrade requirements
database
26.
In an alternate embodiment, the output of the planning module 110 is coupled
to
the output communications interface 32.
The configuration manager 100 stores and retrieves desired configuration data
102 for the evaluation module 108, whereas the configuration monitor 104
stores and
retrieves actual configuration data 106 for the evaluation module. The desired
configuration data 102 may include one or more of the following: a physical
configuration objective, a functional configuration objective, a logical
configuration
objective, an operational configuration objective, a redundant configuration
objective,
and a self healing configuration objective. Similarly, the actual
configuration data 106
may include one or more of the following: observed physical configuration
data,
observed functional configuration data, observed logical configuration data,
an observed
operational configuration data, redundant operational configuration data, and
self healing
operational configuration data.
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The presence and availability of self healing and redundant systems may reduce
the need for maintenance at particular times to maintain the availability of
the equipment
or may lead to more convenient scheduling of replacement for the equipment.
Further,
certain configurations may be modified to increase the level of redundant
equipment such
that repairs can be performed with more regularity or in accordance with a
desired
maintenance schedule that is more efficient for a maintenance service
provider.
The evaluation module 108 accepts input from the configuration manager 100 and
the configuration monitor 104. The evaluation module 108 compares the actual
configuration of an item of equipment to the desired configuration of the item
of
equipment. The evaluation module 108 determines if the actual configuration
complies
with the desired configuration. If the actual configuration does not comply
with the
desired configuration, then the planning module 110 is alerted.
The multiple aspects of the configurations of an end item may be referred to
as a
multi-dimensional configurations where two or more aspects of a configuration
are
present. For example, where two or more of the following aspects of a
configuration are
present, the configuration may be regarded as multi-dimensional: physical
configuration
data, logical configuration data, operational configuration data, a self
healing
configuration data, a redundant configuration, and functional configuration
data.
The observed configuration data for one or more dimensions is compared to the
configuration objective for one or more corresponding configuration dimensions
to
determine whether the actual configuration complies with the desired
configuration. For
example, the observed logical configuration data is compared to the logical
configuration
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objective to determine whether the actual configuration complies with the
desired
configuration. Unanimous or substantial compliance of all considered
configuration
dimensions is generally required to establish compliance of the actual
configuration with
the desired configuration.
The planning module 110 plans an upgrade requirement for upgrading the actual
configuration to the desired configuration if the actual configuration is not
compliant.
Both the evaluation module 108 and the planning module 110 may support multi-
dimensional handling of configurations. Mufti-dimensional means that the
evaluation
module 108 may consider multiple configuration dimensions in determining
whether the
actual configuration data 106 monitored is compliant with the desired
configuration data
102. For example, the evaluation module 108 may consider if two or more of the
following configuration aspects are compliant: a logical configuration, a
functional
configuration, a physical configuration, operational configuration, self
healing
configuration, and redundant configuration. Accordingly, even if the actual
monitored
configuration data is compliant with the desired configuration for one
dimension, the
evaluation module 108 may determine that the actual configuration data 106 is
non-
compliant for another dimension with respect to the desired configuration data
102.
In such a case of noncompliance of the actual configuration with respect to
the
desired configuration, the information is provided to the planning module 110
so that the
planning module 110 may plan for upgrading the actual configuration to the
desired
configuration for the deficient dimension of the item of equipment. For
example, an item
of equipment may comply with a logical and a physical configuration with
respect to the
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desired configuration data 102. However, that same item of equipment may have
actual
co~guration data 106 that is non-compliant with respect to the desired
configuration
data 102 in the operational configuration dimension.
In one example, the compliance of the actual configuration to the desired
configuration requires compliance of the observed operational configuration
data to the
operational configuration objective to assure that the item of equipment
complies with a
minimal level of performance. Accordingly, the predictive maintenance planned
in
accordance with this invention is invoked such that the performance of the end
item of
equipment is maintained. The performance of the item of equipment is
maintained, even
if a reliability or availability of the equipment would not otherwise suffer
because at least
one other configuration dimension besides the operational configuration is
satisfied.
The planning module 110 may be associated with an analyzer (not shown) within
the data processor 30. The analyzer may provide economic information and
reliability
data about the components, assemblies or other parts of an end item of
equipment such
that the planning module 110 can determine one or more of the following: ( 1 )
whether
repair or replacement of a particular component or a particular assembly is
more
appropriate and (2) the timing of the recommended maintenance action or
actions. The
timing of the recommended maintenance activity may include establishing a time
interval
or date for the maintenance activity to foster compliance with a
multidimensional
configuration in a manner that minimizes downtime of an item of equipment.
FIG. 3 is a flow chart of a method for performing predictive maintenance on an
item of equipment. The method of FIG. 3 starts at step S 100.
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In step S 100, the desired configuration of an item of equipment is
established
based on a predictive maintenance target. The desired configuration may be
established
by entering data to the data processing system 16. The desired configuration
may be
established by input of an engineering inputloutput device 12, a supervisory
management
input/output device 14, or both. The predictive maintenance target includes
one or more
of the following: a physical configuration objective, a functional
configuration objective,
a logical configuration objective, an operational configuration objective, a
redundant
configuration objective, and a self healing configuration.objective.
The definitions of physical configuration, functional configuration, logical
co~guration, operational configuration, redundant configuration and self
healing
configuration were previously set forth herein and apply to FIG. 3 with
respect to the
physical configuration objective, the functional configuration objective, the
logical
configuration objective, the operational configuration objective, the
redundant
configuration objective and the self healing configuration objective,
respectively.
The logical configuration objective may define whether a suitable replacement
component, a suitable equivalent component, or a suitable substitute component
exists for
a subject component of an item of equipment. The suitability of the
replacement for a
component may be determined based on empirical data, historical statistics, a
manufacturer's specification, a supplier recommendation, an engineering
recommendation, a governmental requirement, or a manufacturer's recommendation
related to the component or an analogous component.
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The logical configuration may allow similar items of equipment and different
items of equipment to share and interchange components. The sharing of
components
among items of equipment may lead to reduced overall inventory of components
and
improved logistics in managing the acquisition of the components. For example,
the
maintenance provider may reduce the number of components required to maintain
a
group of equipment sharing common components or may increase the size of
purchase
orders to suppliers to cover maintenance of a group of equipment that shares
common
components.
Step S 100 may be carried out in accordance with several alternate techniques.
Under a first technique, the operational configuration objective may be
determined
consistent with an item of equipment meeting a performance metric of a group
of
equipment of the same class or general type as the equipment. Accordingly, the
weak-
performing items of equipment may be weeded out or separated from the stronger
performing items of equipment for implementation of a custom-tailored
maintenance
plan. The weak-performing items may be subject to more frequency predictive
maintenance or retired from service prematurely, for example.
Under a second technique, the logical configuration objective may be defined
as a
decision to substitute a generally suitable replacement component for an
existing
component of the item. The replacement decision may be invoked to the
exclusion of
repairing the existing component.
Under a third technique, a repair versus replacement decision of a component
may
be defined as a logical configuration objective. The determination of whether
to repair or
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replace a component may be determined based on empirical data, historical
statistics, a
manufacturer's specification, a supplier recommendation, an engineering
recommendation, a governmental requirement, or a manufacturer's recommendation
related to the component or an analogous component. In one example, the
logical
configuration objective may represent the decision to repair an existing
component, rather
than substitute a generally suitable replacement component for an existing
component of
the item. In another example, the logical configuration objective may be
defined as a
decision to repair a component, rather than to replace the component in kind,
or vice
versa.
In accordance with a fourth technique for executing step S 100, the
operational
configuration objective may be defined as a measurement of at least one
component of
the item with respect to at least one operating requirement and an associated
operating
environment. Similarly, the operational configuration objective may be defined
as a
measured response of an assembly of the item to at least one operating
requirement and
an associated operating environment. The term "assembly" shall include a
system of the
item of equipment.
In step S 102, an actual configuration of the item of equipment is monitored.
The
monitoring of the equipment may be carried out in any of the following ways:
(1)
manually by physical inspection of the equipment, (2) via performance reports
made
during use of the equipment, or (3) automatically by sensors mounted on the
equipment
that report back to a configuration monitor 104 in the data processing system
16. The
observed dimensions of the actual configuration may include one or more of the
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following: an observed physical configuration, an observed functional
configuration, an
observed logical configuration, and an observed operational configuration, an
observed
self healing configuration, and an observed redundant configuration.
The reliability of the item of equipment may be enhanced by the incorporation
of
redundant components in the actual configuration. Similarly, the reliability
of the item
of equipment may be enhanced by the incorporating a self healing system into
the actual
configuration. The self healing confirmation and the redundant components may
increase the flexibility in scheduling maintenance, as well as reducing
downtime or
inoperable durations of the equipment.
In step S 104, the data processor 30 determines if the actual configuration
complies with the desired configuration. The actual configuration and the
desired
configuration may be compared on the basis of one or more configuration
dimensions. In
accordance with the invention, the actual configuration and the desired
configuration are
preferably compared in two or more dimensions. If any one of the two or more
dimensions are deficient then the actual configuration does not comply with
the desired
configuration. Accordingly, if the desired monitored configuration does not
comply with
the desired configuration, then the method continues with step S 106. However,
if the
actual configuration does comply with the desired configuration on a multi-
dimensional
basis, then the method continues with step S 108.
In step S 106, a planning module 110 of the data processor 30 plans an upgrade
requirement or maintenance plan for upgrading the actual configuration to
comply with
the desired configuration. The upgrade plan may only address the deficient
dimension or
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deficient dimensions of the actual monitored configuration of an item of
equipment. The
compliant dimensions of the configuration may not be addressed by the planning
module
110.
In step S 108, the data processor 30 maintains the actual configuration until
the
actual configuration no longer complies with the desired configuration in at
least one
dimension. When the actual configuration no longer complies, then the planning
module
110 may be invoked to propose the necessary resultant maintenance plan to
correct the
deficiency.
The method and system of the invention not only promotes availability and
reliability of an item of equipment, but rather promotes management of the
predictive
maintenance of an item of equipment in a proactive manner that may be used to
manage
costs of predictive maintenance. The cost savings of the predictive
maintenance may
result in the specification of multi-dimensional configurations that support
definitions for
the interchangeability of parts, components, assemblies, and systems of
different items of
equipment. The support for the interchangeability of components and the
performance
of predictive maintenance may lead to a reduction of inventory of components
associated
with conducting a certain level of predictive maintenance. Further, the items
of
equipment may be analyzed with reference to the degree of interchangeability
of
components such that capital expenditures for new equipment will be consistent
with
existing equipment on an interchangeability basis.
The economic considerations in the repair or replacement may lead to cost
savings for the maintenance service provider. Because the actual
configurations are
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compared with the desired configuration on a mufti-dimensional basis, the
predictive
maintenance may be used to proactively manage the predictive maintenance of
end items.
Where an end item of equipment contains self healing systems or redundant
systems, the
maintenance may be delayed or scheduled to coordinate the maintenance with
other
maintenance activities, for example. Further, the supervisory management
input/output
device 14 and the engineering input/output device 12 support the re-definition
of a
desired configuration such that a desired configuration may incorporate a self
healing
system or a redundant system for the purpose of making predictive maintenance
more
convenient or economical for the service provider.
The foregoing description of the invention describes several illustrative
embodiments. Other embodiments, variations, alterations or alternatives may
fall within
the scope of the invention and the following claims. Accordingly, the claims
should be
accorded the broadest interpretation possible consistent with the
specification set forth in
the description.
