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Light Armored Vehicle (LAV):Degrader Study and

Asset Health Monitoring

DoD Maintenance Symposium 2003

Jeffrey BanksThe Pennsylvania State University

Applied Research Laboratory(814) 863 3859

jcb242@psu.edu

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Light Armored Vehicle (LAV-25)Degrader Study

• Crew: Driver, gunner, commander and 6 Marine infantry

• Combat Weight: 28,200 pounds • Range: 410 miles • Land Speed: 62 mph • Swim Speed: 6 mph • Length & Height: 21 feet by 9 feet

• LAV Degrader Study was conducted to assess the issues related to vehicle availability and reliability.

• Analysis focused on identifying components and sub-system degraders of vehicle mobility.

• Study involved four evaluation sections:– Parts Supply Data– Interviews with Maintainers– Failure Modes and Effects

Analysis (FMEA)– Severity Rankings

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LAV Degrader Study: MIMMS data

• Analysis of Maintenance Information Management System (MIMMS) data:– Number of parts replaced/year– Logistic Delay Time

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LAV Degrader Study: InterviewsTwenty Interviews with Experienced Maintainers were Conducted

– Assess maintenance issues with LAV at:• School House - Aberdeen Proving Grounds - Aberdeen, Maryland• Exercise Support Division – Twenty Nine Palms, California• 3rd LAR Bn. - Twenty Nine Palms, California• 1st LAR Bn. – Camp Pendleton, California• School of Infantry – Infantry Training Bn. – Camp Pendleton, California• PMO-LAV - Albany, Georgia• 2nd LAR Bn. – Camp Lejeune, North Carolina

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LAV Degrader Study: FMEA• Failure Modes and Effects Analysis (FMEA): process to

define and evaluate vehicle degraders.– Effective tool for evaluating asset health monitoring technology.

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LAV Degrader Study: Severity

• Severity Analysis: The consequences of the failure in terms of operation availability of the vehicle and maintenance issues for each component. – Severity levels based on four factors:

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LAV Degrader Study: Results

LAV Mobility Degraders:• Differentials• Batteries• Planetary Gear Set in

Wheel Hubs• Alternator• Transfer case• Seals• Fuel Pump• Vehicle Hydraulic

System• Diesel Engine • Transmission

Identify Top Vehicle Degraders

Develop and Implement Vehicle Health Monitoring System

Field Test and Evaluate Health Monitoring System

Limited Scale Field Testing: 3 to 5 Vehicles

Differentials Batteries

Penn State ARL LAV Test Vehicle

Deploy Health Monitoring System to All Fleet Vehicles

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Diagnostic System: Systematic Design Approach

DataData InformationInformation DecisionDecisionKnowledgeKnowledge

TechnologyTechnology

IntelligentIntelligentNodesNodesIntelligentIntelligent

NodesNodesSmartSmartSensorsSensors

EnterpriseEnterpriseMonitor/Monitor/ControlControl

SubsystemSubsystemIntelligentIntelligent

NodesNodes

SystemSystemHealthHealth

MonitorMonitor

ActionAction

CollectCollectraw dataraw data

Perform Perform assessmentassessment

MakeMakediagnosisdiagnosis

ReduceReducedatadata

Science Science

AnalyzeAnalyzedatadata

SensingSensing FeatureFeatureExtractionExtraction

FaultFaultDetectionDetection

DamageDamageEstimationEstimation

Feature Feature TrackingTracking

& Prognostics& Prognostics

Engineering ImplementationEngineering Implementation

SensorsSensors HW/SWHW/SWArchitectureArchitecture

Comm.Comm.ArchitectureArchitecture

Comm.Comm.NetworkNetwork

HumanHuman--toto--MachineMachineInterfaceInterface

Open Systems ArchitectureOpen Systems Architecture

RCM/RCM/FMECAFMECA

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Differential Diagnostics: Lubrication Level

• LAV maintainer interviews indicated that the root cause of failure for differentials is lubrication loss.

• Need earliest indication of lubrication loss to prevent damage to differentials.

• Solution: Use vibration analysis to detect lubrication loss.

• Benefit: Vibration can be used to detect faults in bearings, gears and shafts as well.

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Differential Diagnostics: Lubrication Level

• Trending of narrowband data provides an early indication of loss lubrication

LAV Differential Lubrication TestFullband: 0 to 51.2 kHz

1000030000500007000090000

110000130000150000

Full Lube 50% Lube No Lube

Lubrication Level

RM

S

Control - Diff No.3 Test - Diff No.4

LAV Differential Lubrication Test Narrowband: 15kHz to 24kHz

0100020003000400050006000700080009000

10000

Full Lube 50% Lube No LubeLubrication Level

RM

S

Control - Diff No.3 Test - Diff No.4

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Battery Prognostics: Remaining Useful Life

MeasurementSignals

Neural Network

Fuzzy Logic

ARMA

User Interface

ImpedanceProcessing

Heat CapacityProcessing

Electrochemical ModelIdentification

SOC, SOH, andSOL Estimators

V,I

Ex,Sn

T

Feature VectorFiles

Feature Processing

SOC, SOH, SOLEstimation FIles

Data Fusion WorkbenchUser Info

File

HistoryKnowledge

Decision FusionHistory

Knowledge

Σ

if,...then

Patent #6,307,378 [Grant N00014-98-1-0795]

• Fast, reliable predictions of SOC, SOH, and SOL with performance errors <5%

• A low power system (<1/2 watt) that is embedded in a battery, equipment using the battery, or hand-held meter

Causes of Battery Failure•Aging: dry-out,dendrites; passivation; corrosion•Charging: overcharge; low electrolyte charging• Mechanical/Vibration: case cracks; broken plates

- Damaged or faulty battery not detected until attempted engine start

- Remaining time not accurately known while using only battery power

- Remaining engine starts using the vehicle batteries not known

- Impending battery faults not detected

Need for Battery Prognostics

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Location• Vehicle identification• Location (GPS)• Time-of-day

Location• Vehicle identification• Location (GPS)• Time-of-day

Condition MonitoringIntelligent Nodes

RFNetwork • COTS Hardware

• PC Based Architecture• Modular PC104 boards

802.11 NetworkOr SINCGAR’sW/Data Modem

Diagnostic Monitoring

Unit

Asset Visibility Intelligent Node

ReadinessIntelligent Node

LAV Monitoring System Layout(Demonstration Hardware)

Condition/Health• Engine Health

Information• Power Train Health

Information• Battery Health and

State of Charge

Condition/Health• Engine Health

Information• Power Train Health

Information• Battery Health and

State of Charge

Performance/Status• Warnings• Advisories• Status, levels

Performance/Status• Warnings• Advisories• Status, levels

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Vehicle and Systems Health Information