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The eDAQ-lite is a commercial off-the-shelf data
acquisition system that can provide onboard selfdiagnosis
and self-reporting of a tactical wheeled
vehicle’s health.
algorithms. Although AMSAA is able to use a commercial
off-the-shelf (COTS) system to collect data in
the test environment, the system must be militarized
for the intheater environment.
Testing in an intheater environment is also beneficial.
It provides immediate value by giving insights
into real-world vehicle usage by Soldiers and the
effect this usage can have on the prognostic algorithms
that are being developed based on vehicle
usage in a test environment. Installing HUMS in a
theater provides a validation and verification process
to determine if prognostic algorithms developed in a
test environment are applicable to vehicles being used
in current operations.
Vehicle Data Acquisition System
AMSAA engineers identified a rugged and modular
COTS data acquisition system (eDAQ-lite) that
has the functionality, flexibility, and ease of use
needed to support the development of CBM and prognostic
HUMS (PHUMS) algorithms and processes.
(See photo above.) This system complies with the
Army Integrated Logistics Architecture and with
the CLOE strategy for onboard self-diagnosis and
self-reporting of a vehicle system’s health. It is also
100-percent compatible with current AMSAA data
analysis software (Glyphworks, Matlab, and Math-
CAD) and processes.
The COTS vehicle data acquisition system that will
be used on tactical wheeled vehicles must—
• Be dust- and water-tight.
• Be small in overall size.
• Have robust, military-grade cable connections.
ARMY LOGISTICIAN PROFESSIONAL BULLETIN OF UNITED STATES ARMY LOGISTICS
• Accept 12- and 24-volt power inputs.
• Provide a method for remotely switching the unit
on and off.
• Be compatible with the vehicle bus, GPS, and
displacement, strain, acceleration, and temperature
gauges.
• Operate in maximum outside ambient temperature
of 49 degrees Celsius (120 degrees Fahrenheit) with a
solar radiation load up to 1,120 watts per square meter.
• Meet conducted emissions and susceptibility
requirements of Military Standard 461, Requirements
for the Control of Electromagnetic Interference Characteristics
of Subsystems and Equipment.
• Survive the vibration levels typically experienced
by various tactical wheeled vehicles.
The base of eDAQ-lite contains the computer processing
unit, memory, serial communications port,
power circuitry, and battery backup. The layers, which
are interchangeable and removable, contain the circuitry
for handling analog and digital signals: the bridge
layer for analog signals and the digital input/output for
digital signals.
The eDAQ-lite design has some limitations. It
was designed for industrial use, meaning use in an
operating temperature of -10 to 65 degrees Celsius
and with an operating voltage of 10 to 18 volts, and it
has industrial-grade connectors. It has no additional
electromagnetic interference (EMI) shielding and no
tests for EMI, no internal relay for switching the unit
on and off, and no internal motion sensors. Finally,
the vehicle engine bus interface module is external to
the unit.
Modifications and Additions to eDAQ-lite
To ensure the survivability of eDAQ-lite in the field,
enhance its functionality, and control EMI to and from
communications gear, AMSAA made a few changes
and additions. First, a military-grade superstructure
was designed in Pro/Engineer (a three-dimensional
computer package for modeling solids) to house the
eDAQ-lite data acquisition system and other essential
support equipment and cables.
Support equipment also was added, including EMI
filters and fuses on the power lines; a direct current/
direct current converter to enhance the operating voltage
range from 10 to 18 volts to 9 to 36 volts and
provide protection against under- and over-voltages;
a solid-state relay to switch the eDAQ-lite on and
off; a motion pack to provide three angular rates and
acceleration information along three orthogonal [rightangled]
directions; and a vehicle bus interface module
to provide communication between the vehicle bus and
the eDAQ-lite.
Two thermal tests were performed to characterize
the thermal behavior of the resulting Army eDAQ
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