Display image.
can get caught or snagged on wires or debris.
I used a Keller Preciseline 0328.14903.050500 digital
pressure transmitter (
www.kelleramerica.com/above-ground-pressure-transmitters/) to provide a reading of the
current pressure of the backpack wearer’s on-board tank
(containing compressed breathing air). The digital pressure
transmitter connects to the main circuitry via an industry-standard RS-485 bus ( http://en.wikipedia.org/wiki/EIA-
485/). It transmits a data stream (corresponding to the
current pressure of the tank) to the BASIC Stamp 2sx. The
BS2sx converts the data into a percentage of remaining
breathing air based on a full tank pressure of 3,000 PSI
(pounds per square inch) and overlays the result on the
headset’s microdisplay.
Firefighter Identification
System
In many situations — particularly firefighting endeavors
such as search and rescue — it is extremely difficult or
impossible for a firefighter to identify other firefighters
within a low- to no-visibility environment, such as a dark
PyroPack Electronics System Block Diagram
Digital Pressure
Transmitter
Keller Preciseline
0328.14903.050500
Microprocessor
Parallax BASIC
Stamp 2sx
Accelerometer
Memsic 2125GL
Two-Axis
On-Screen Display
Interface
Decade Engineering
BOB-4-H
Radio-Frequency
Identification Reader
Parallax 28140 RFID
Reader Module Serial
Power Supply &
Regulation Circuitry
RS485
Infrared Thermal Imaging
Camera
L- 3 Communications
Thermal-Eye 3600AS
OEM
Heads-Up Display
eMagin SVGA OLED-XL
Microdisplay w/ WFO5
Prism Optic & Module
June 2010
Head-Mounted Enclosure
or smoke-filled room. The intent of the PyroPack’s
Firefighter Identification System is to allow a simple, quick,
and effective method for a firefighter to identify other
firefighters with minimal interruption to their primary job.
Typically, identification consists of one firefighter
approaching another firefighter and yelling “Who are
you?” which is not always effective. While the headset’s
thermal imaging camera allows the firefighter to visually
locate a human, it does not provide them with any
identifying markers about who the human is or what his
or her role is. The Firefighter Identification System
supplements the thermal imaging camera by properly
identifying the target after it has been located.
The PyroPack uses a handful of low-cost RFID tags
embedded into the Firefighter’s regulation clothing at predetermined positions (for example, left and right
shoulders, back of neck, left and right chest, left and right
hamstrings, left and right quadriceps, etc.). Each RFID tag
contains a unique identifier that can be read by a Parallax
RFID reader module (search for product code ‘28140’)
which is mounted on the wearer’s arm and connected via
four-wire cable to the PyroPack’s main circuitry. When the
RFID reader module comes within approximately three or
four inches of an RFID tag, the unique identifier of the
RFID tag will be received by the reader and processed
accordingly. The BS2sx is pre-loaded with a look-up table
of known RFID tag unique identifiers and corresponding
identification information. For example — for our
prototype — eight unique IDs are associated with a single
firefighter (allowing greater dispersion of RFID tags on the
firefighter’s clothing which, in turn, allows for a greater
chance of the RFID reader module coming in close
contact with a tag) and four firefighters are supported. Of
course, in a real-world situation, the look-up table would
need to be updated on-the-fly and/or in the field in order
for the system to always have the most accurate
identifying information.
In our prototype, when a valid RFID tag is read the
last name of the firefighter is displayed on the
microdisplay. The identifying information can be changed
to any desired
textual or graphical
information,
including (but not
limited to) full name,
rank, engine number,
or role. Furthermore,
the Firefighter
Identification System
could be easily
expanded to not
only identify
firefighters, but also
provide quick
detection of
entrance or egress
points (for example,
Inside The Pack
42
