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THE ARI PROTOTYPE SMALL GUN LASER

ENGAGEMENT SYSTEM

~~~ Gary Kress and Stephen C. Bradshaw

Army Research Institute for the Behavioral and Social Sciences

and

Robert L. McFarland and Jerry L. Ashley Manned Systems Sciences

I ~~~~~~

ARI FIELD UNIT AT FORT ORD, PRESIDIO OF MONTEREY , CALIFORNIA C)

t LU

0 p C

U. S. Army

Research Institute for the Behavioral and Social Sciences

Nov•m b.r 1978

Approvsd for public relaue; distribution unlimited.

79 02 ~~)

• —.- ___________________
U. S. ARMY RESEARCH INSTITUTE

FOR THE BEHAVIORAL AND SOCIAL SCIENCES

A Field Operating A gency under the Jurisdiction of the

Deputy Chief of Staff for Personnel

WILLIAM L. HAUSER

JOSEPH ZEII)NER Colonel , US Army

Technical Director Commander

Research accomplished under contract

to the Department of the Army

~~~0

Manned Systems Sciences ,

~~ /

~ 

/ ,

. 

.

~~~~~~~~~~~~~

~~~~ ~~~~‘

NOTICES

DISTRIBUTION Prum.ry distribution of this report has bun mcdi by API. Plea,. sddr.se correspondence

concerning distribution of reports to: U. S. Army Research Inatitut

~ for ths Bittivioril and Social Sci.nc s. ATTN. PERt- P . 5001 Eisenhoiser Avenue . Alexandria , Virginia 22333

IINAL DISPOSITION: This report may b. deitroyld whin it is no longer ne d.d, Pi. ., do not return It to

th. U. S. Army Rigp.rch Institute for th. Beh.vuor.l md Sociel Sciences.

~~~~ The findings in this report .rc riot to be conitrued .s an off ci.l D p.rtm.nt of th. Army position,

uflliu 10 designated by ottwr •uthorilid documunts.
( T ~~~~~r

f1n r’1assifi

~ d SECURITY CLASSIFICATION OF THIS PAGE (WPi.r 0.t. Ent.r.~~

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1 DAt- C READ !NSTRUCTIONS ,

~Lr tj,~ . us,~.vm rs S U ~~~ r ‘~~ iI

~ BEFORE COMPLETING FORM U ORT NUMBER 2. GOVT ACCESSION NO RECIPIENT’S CATALOG NUMBER

Technical Paper 318 (

~ ~ 

) 4. TITLE ~ ‘S~~~ Pa’. 0 COVERED

~ TW ~~~~~~~~~ E~~ MALL GUN I

~~SER ENGAGEMEN~J L~~a1 I

~~~’

3

~T

6. PERFORMING ORG. REPORT NUMBER

- — P.~~

AL1T5Io~~r 1 ~~ ~~~ CONTRACT OR GRANTNUMBER(.)

I GarY/Kress1 Stephen C. Bradshaw ü L,-ua4 / /

I Robert L./ McFarland Jer Ashley l (Manned I. 1 ~~~~~~~~~~~~~~~~~~~~~~~~ _________________ 1 \._. ( __ ..... ._.

C PERFORMING ORGANIZATION NAMEy ID .

AODR tO PROGRAM ELEMENT PROJECT TASK

/ ~

- . AREA & ~~~~~~~~ “

~~~~~ 5I1MBERS Manned Systems Sciences.,

~vNorthridge , C~ 91324~

i

~ ,-g—

U.S. Army Research ~pstitute for the Behavio 4]/~ 1 2Q162722A764 j

and Social Sciences, Alexandria, VA 22333 ‘

s’.. .1—

II. CONTRO %.LINO OFFICE NAME AND ADDRESS 1 

~~~~~~~~~~~~~~~~~

Deputy Chief of Staff for Personnel 

~~~~~ 

~~OV....L..... t

~

7

~J Washington , DC 20310

14. MONITORING AGENCY NAME & ADDRE$3(St dlli.,snt fto ~ Cunfrollhs~ ONto.) IS. SECURITY CLASS. (of tAt. rspotf)

U.S. Army Research Institute for the Behavioral Unclassified

and Social Sciences, Alexandria , VA 22333 iS.. DECLASSIFICATION/DOWNGRADING

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Approved for public release ; distribution unlimited.

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IS. SLJP L.EMENTARY NOTES

IC. KEY WORDS (C.n*Mu. on ,.,.ra. .ld. If n.c... y mid ld.nU~ ’ by block nionb.r)

Engagement simulation

Tactical training

Laser weapon simulators

zS AsIyAcT (r ~

__ ~~

_.

~ — ,s.u ..____. tdeselfr by block nas,bas)

This report describes a research and development effort aimed at determining the feasibility of developing a small gun laser engagement system for

field research and evaluation purposes. The prototype system developed has a

capability for ~

a~ ’

~~ealistic shooter performance requirements and “eapun s

signature , ~~~ realistic simulation of weapons effects in terms of realtime casualty assessment and suppression , and çe~~~ iayer-carri.d memury for

collecting and recording time , casualty, and player identification data .....,,. ( continued)

DO ~~~~ W3 505750sf OF 5 NOV us is 05505 175 Unclgssified

Il 9 s

~~r o ~

m ’

~~~

bn

~~~ _ 3

~~~ 

a’yJ A~
Unclassified SECURITY CLASSIFICATION OF THUS PAGE(Wh.n Data tn1.esd ~

20.

The prototype laser simulator demonstrates that the requirements for casualty

assessment and data recording necessary for field research can be met using

this system. Further research and development are necessary to make the

system fully operational .

Unclassified

SECuRITY CLASSIFICATION OF THIS PAG~ (05on Data R.stpon Ø
Technical Paper 318

THE ARI PROTOTYPE SMALL GUN LASER

ENGAGEMENT SYSTEM

Gary Kress and Stephen C. Bradshaw

Army Research Institute for the BehavIoral and Social Sciences

and

Robert L. McFarland and Jerry L Ashley Manned Systems Sciences

ARI FIELD UNIT AT FORT ORD, PRESIDIO OF MONTEREY , CALIFORNIA

Submitted as complete and Approved by: technically accurate, by:

Jack J. Sternberg A.H. Blrnbaum, Acting Director

Field Unit Chief ORGANIZATIONS & SYSTEMS

RESEARCH LABORATORY

Joseph Zeidner

TECHNICAL DIRECTOR

U.S. ARMY RESEARCH INSTITUTE FOR THE BEHAVIORAL AND SOCIAL SCIENCES

5001 Eisenhower Avenue, Alexandria, Virginia 22333

Offic., Deputy Chief of Staff for Personnel

Dsp.rtnwnt of the Army

Nov.m b.r 1978

I

Army Project Number Contract Tactical Team Performance 20152722A764 DAHC 19~

7O~C•O018

- 

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 

- —____
ARI Research Reports and Technical Papers are intended for sponsors of

R&D tasks and other research and military agencies. Any findings ready for

implementation at the time of publication are presented in the latter part of

the Brief. Upon completion of a major phase of the task, formal recommendations for official action normally are conveyed to appropriate military

agencies by briefing or Disposition Form.

-~~~
FOREWORD

The research program of the Tactical Team Performance Work Unit

of the U.S. Army Research Institute for the Behavioral and Social Sciences is conce rned with increasing the effectiveness of team performance

within Infantry, Armor , and Combined Arms units. Experiments are fielded

having application to training and evaluation system effectiveness

(ARTEP) , extensions of engagement simulation methodology (SCOPES ,

REALTRAIN) , and combat developments (tactics and techniques). Technological Base Exploratory Development research supporting the continuous

refinement of technological and methodological capabilities for the conduct of research in these areas is conducted under RDT&E Project

2Q162722A764 , Training and Education , FY 78 Wo rk Program .

The present publication describes a prototype small gun laser engagement system incorporating capabilities both for the tactically realistic simulation of individual—weapon (M—16 rifle) effects and for the

collection of data on the development of firing engagements. Application of the system to other individual and crew—served direct-fire weapon

systems is shown to be feasible .

ARI technological base research is conducted as an in—house research

effort augmented by research contracts with organization s selected as

having unique capabilities for work in the area. The present developmental effort was conducted jointly by ARI personnel under the supervision of Dr. Jame s H. Banks and by personnel of Manned Systems Sciences,

Northridge , Calif., under the supervision of Mr. Douglass Nicklas. The

work was conducted under a program directed by Mr. Jack J. Sternberg,

ARI.

O PH ZE R

ical Director
THE ARI P~~ TOTYPE SMALL GUN LASER ENGAGEMENT SYSTEM

~RIEF

Requirement :

To determine the feasibility of developing a small gun laser engagement system for field research and evaluation purposes.

Procedure:

Taking advantage of the latest developments in the state—of-the-art

in laser technology and in packaging and miniaturization of electronic

circuitry, ARI and contractor scientists and engineers developed and refined the design of a small gun laser engagement system (LES) to meet the

requirements of field testing and experimentation . The approach taken

was the concurrent development of three subsystems comprising the whole :

a laser transmitter mounted on the M—16 rifle, a helmet-mounted laser receiver , and an off—line computer which receives the data from the receiver

memory , reformats the data, and performs data reduction and analysis.

Findings:

The prototype LES demonstrates that the requirements for casualty

assessment and data recording necessary for the conduct of field research

can be met using this system.

Through achievement of a virtually constant hit-zone , the system

provides accurate simulation of weapon effects out to the maximum effective range of the weapon . Players under fire receive real—time feedback

on hits and near misses f rom helmet-mounted audio alarms.

Helmet-mounted memory provides for storage of time-tagged shooter

identification, target identification , hit and near-miss data , and round

count . This feature permits a stand-alone capability independent of online computer support.

The system is unobtrusive and does not degrade tactical realism:

There is no external cabling to encumber the player; the small, lightweight transmitter and receiver alter neither weapon balance and aiming

requirements nor helmet balance .
The system is safe and easy to use : Low—energy laser diodes permit use at close range ; the laser transmitter in continuous pulse mode

permits rapid and accurate weapon zeroing; and the transmitter can be

easily and quickly removed from the weapon and need not be rezeroed

when remounted.

The design concept , using multiple laser beams, can be adapted to

a variety of direct—fire weapon systems.

Utilization of Findings :

The system has application -to field research on a broad spectrum

of Army problems , including the development of techniques for

• Assessment of combat readiness ,

• Assessment of training effectiveness ,

• Diagnosis of individual and unit training requirements ,

• Evaluation of variations in tactics and doctrine , and

• Evaluation of variations in unit size and composition .

-S - -

~~
THE ARI PROTOTYPE SMALL GUN LASER ENGAGEMENT SYSTEM

CONTENTS

Page

BACKGROUND 1

PURPOSE 1

SYSTEM DESCRIPTION 2

General 2

Laser Transmitter 5

Trigger Mechanisms 5

Timing and Control Logic 11

Laser Dibdes and Trigger Packs 12

Collimating Lens 13

Beam Geometry 13

Transmitter /Helmet Data Link 16

Power 18

Transmitter Housing and Mounting 18

Laser Receiver 21

Detector 21

Timing and Control Logic 23

Scoring Logic 23

Memory 25

Real-time Display Device 25

Audio Hit Indicator 25

Receiver Power 26

Receiver Packaging and Mounting 26

Computer 26

APPENDIX A. LES SPECIFICATIONS 31

B. LASER SAFETY 33

C. ACOUSTICAL TRANSDUCER 39

D. LASER TRANSMIT1ER LOGIC FLOW CHART 41

E. LASER PACKAGE 43

F. LENS OPTICS 45

G. POWER 47

•1 

_____ 

___________________ ____ ________
Page

APPENDIX H. SYSTEM EQUATION AND SIGNAL-TO-NOISE

RATIO ANALYSIS 51

I. LASER RECEIVER FLOW CHART 57

J. MEMORY INTERFACE DEVICE 59

K. LES DISPLAY DEVICE 63

DISTRIBUTION 69

LIST OF TABLES

Table 1. Scoring logic for beam pattern 24

LIST OF FIGURES

Figure 1. Rifle-mounted laser transmitter and helmet-mounted

detectors/receiver 3

2. Laser transmitter and receiver 4

3. Rifle— mounted laser transmitter——three quarter

front view 6

4. Rifle-mounted laser transmitter——three quarter

rear view 7

5. Laser transmitter block diagram 8

6. Transmitter mechanical cutaway--end view 9

7. Transmitter mechanical cutaway——side view 10

8. Timing diagram for one firing cycle 11

9. Fiber optic tube configuration 12

10. Quad trigger pack schematic 14

11. Overlapping beam-pattern configuration 15

12. Range invariant beam—size concept 17

13. Helmet-mounted sensor/receiver subsystem 19

14. Laser receiver block diagram 20
Page

15. Closeup of laser detector 22

16. Receiver electronics 27

17. Receiver electronics configuration 28
THE ARI PROTOTYPE SMALL GUN LASER ENGAGEMENT SYSTEM

BACKGROUND

The Army Research Institute for the Behavioral and Social Sciences

(ARI ) has been engaged in an in—house research and development program

aimed at determining the feasibility of developing, for research purposes, a small gun laser engagement system (LES). The LES would be a

major instrumentation element of the Combat Readiness Systems Measurement Bed (CORE-TEST) being developed for use in experimentation and

testing of small infantry unit tactical performance . Wi th a LES capa- -

bility, the system measurement bed would (a) provide for tactically

realistic simulation of small arms weapons fire , (b) permit two-sided

free play with realistic , real-time casualty assessment and suppression

by fire, and Cc) provide standardized task and evaluation situations

and measurement and recording techniques for the systematic and reliable

assessment of individual and unit tactical performance .

A major requirement for the LES is that it provide good—fidelity

small arms weapons simulation , casualty assessment, and data recording

without being tied to an expensive and complex on—line computer system.

To meet this requirement, the present prototype system utilizes a blank—

activated gallium arsenide (GaAs) laser source mounted on the M—l6 rifle

to simulate weapon firing, and a pulse—coded beam pattern transmission

to identify the player who is firing. Wide-field—of-view optical detectors mounted on each player’s helmet allow him to be “hit” or “suppressed” if he is illuminated by the laser beam pattern. Audio alarms

in the helmet notify a player if he has been hit or suppressed. Time,

casualty , and player/weapon identification data are recorded in playercarried electronic memory modules.

PURPOSE

The purposc of this report is to describe the physical and functional characteristics of the prototype ARI small gun laser engagement

system. The scope of the research and development effort is presently

confined to the simulation of M—l 6 rifle fire. This capability probably

cam be extended to other infantry squad weapons (e.g., M-60 machine

guns) if the present system is modified. The system and its components

are described below . The appendixes provide more detailed technical

coverage of particular system components; Appendix B discusses the eye

safety of the system.
SYSTEM DESCRIPTIOW

Gene ral

The prototype ARI small gun laser engagement system consists of

three major subsystems. When integrated, they provide simulated small

arms fire , real—time casualty assessment , time—tagged data storage ,

and off-line data reduction and analysis. The three subsystems include

the following :

1. A laser transmitter, mounted on an M—l 6 rifle , that consists

of GaAs laser diodes and associated electronics, optics, and

a power source ;

2. A helmet-mounted laser receiver consisting of silicon photodiode detectors, a power source, receiver electronics, memory

for data storage, and an acoustic hit indicator; and

3. An off-line computer that receives the data from the receiver

memory, reformats the data, and performs data reduction and

analysis.

Figure 1 shows the mounted system. The laser transmitter is

clamped to the slipring immediately in front of the carrying handle of

the weapon. The laser detectors and receive r power supply are mounted

on a band fitted around the circumference oi the helmet liner. The

receiver electronic package , memory , and acoustic indicators are mounted

inside the helmet liner. All system components are contained in either

the transmitter package on the rifle or the detector/receiver package on

the helmet. There are no cables connecting these subsystems.

Figure 2 shows a closeup of the laser transmitter on the right and

the he lmet—mounted receiver on the left.

The laser transmitter contains four laser diodes arranged in a

square matrix that , when pulsed , produce an overlapping beam pattern at

the target. The diodes are pulsed individually according to a predetermined timing sequence. The timing code permits identification of the

weapon being fired and the beams that illuminate the target .

The receiver detects and decode s the pulses to determine which

portion of the pattern was received. The decoding electronics establish the identification of the shooter, whether a hit occurred , or

the direction of a near—miss . Acoustic indicators notify the target

that he has been hit and put out of action or that he has been nearmissed and perhaps suppressed. When a hit is scored on a target player,

he deactivates his weapon so that it can no longer fire, and he remains

in place as a casualty.

The data gathered during these operations are tagged and stored

in the receiver u~ mory for posttrial readout.

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Rifle - mounted lase r t ran· mi tter and helme t - mounted 

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Laser Transmitter

The rifle-mounted laser transmitter is shown in Figures 3 and 4.

The transmitter is mounted above the carrying handle of the M-l6 in

such a position that balance , sighting, and handling characteristics

of the weapon are not disturbed. No cable connections exist between

the rifleman and his weapon . -

Figure 5 shows a block diagram of the laser transmitter. The components include an acoustic transducer that is activated when a blank

round is fired and thus initiates the laser firing sequence . (An internal trigger is also provided for test purposes.) The timing and control logic controls the firing sequence of the laser diodes. The power

regulator provides low-voltage inputs to run the timing and control

logic and high-voltage inputs to charge the trigger packs that pulse

the diodes. The feedback link contains a light-emitting diode (LED)

that provides round—count information back to the receiver memory

through the detectors in the shooter’s helmet . Figures 6 and 7 ar~ mechanical cutaways of the transmitter housing showing the physical

location of the various components .

Trigger Mechanisms

Acoustical Transducer. The laser transmitter is activated by an

acoustical transducer that detects ar1d discriminates the soun d of the

blast from other weapon—produced sounds. The transducer is mounted

in a small insulated compartment in the transmitter clamp assembly

(Figu re 6). The transmitter itself is clamped to the weapon so that

the transducer compartment is close to the gas port near the base of

the carrying handle .

The transducer element is a small dynamic earphone consisting of

a metal plate suspended on a diaphragm whose frequency response is in

the audio range . When the weapon is discharged , the pressure wavefront

emerging from the gas port vibrates the diaphragm, which in turn drives

a pickup coil into a step—up transformer. The transformer’s output is

wired into a transistor discriminator that rejects all noises except

that of the rifle blast . The output of the transforme r is interfaced

to the timing and control module by a single transistor. Appendix C

contains additional information on the acoustical transducer.

Automatic Trigger. The transmitter package contains a selector

switch (Figure 6) that allows the lasers to be internally pulsed. In

this “test mode ,” the laser is automatically pulsed at approximately

one shot per second. This internal trigger function allows (a) the

lasers to be tested for reliability, and (b) the transmitter to be

boresighted simply and without requiring that the rifle be fired . This

feature saves ammunition and greatly facilitates boresighting.

5
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Figure 3. Rifle-mounted lase r transm1tter, three quarter front view. 
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Figure 6. Transmitter mechanical cutaway--end view.

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Timing and Control Logic

The timing and control logic that controls the diode firing sequence consists of a crystal clock , a counter, and the main controller.

When a trigger pulse “signal” is received , the controller enables the

master clock and the main counter. The counte r is synchronized with

the input trigger pulse and starts from a zero count . Thus the counter

initiates the laser pulse train at a known time from the trigger pulse.

Each laser beam is shot at a preset time during the firing cycle so

that the laser receiver can differentiate and identify the beams . When

the last beam pulse has been fired, the counter resets the main controller to its initial state and waits for the next firing signal (trigger pulse).

Figure 8 shows the timing diagram for one firing cycle. In a normal pulse sequence, all four laser diodes are simultaneously fired to

give a synchronization (sync) pulse ; the rest of the firing cycle follows automatically . This first pulse, if on target , establishes the

initial shooter—target pairing and enables the receiver timing and

control logic to decode the message contained in the remainder of the

pulse train. Following the initial sync pulse , another four-laser pulse

is fired , in 1 of 32 time—encoded slots , to identify the weapon firing.

The four diodes are then fired individually in a specified sequence at

specified delay intervals to provide the identification codes of the individua l beams .

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Sync F 32 firer ID slots I scoring

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F Message length 400 lisec

Figure 8. Tiluin9 -‘.ø~

jran1 for one firing cycle .

When a target sensor is illuminated by these laser beams, the

receiver electronics decodes the pulse sequence to determine from

which weapon the laser beams originated, as well as the actual individual beams by which the target sensor is being illuminated. Thus,

the receiver has all the information necessary to determine beam pattern , which is the basis for scoring hits and near—misses. Appendix D

shows the logic flow chart for the laser transmitter.

ii.
The total message length from sync pulse to the last beam-patt~

.erh

pulse is approximately 400 microseconds (

~

isec) . The maiori.~

ty 5! this

time is used in the timeslotting for the iden - - i

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fication pulse . An individual laser~pulse—actua1ly takes 100 nanoseconds. Once a firing sequence has started , the electronic controller rejects any new triggering

pulses until half the cyclic time of the firing cycle has elapsed. This

procedure ensures that only one laser message is fired for each rifle

shot fired.

To ensure high reliability and minimum power consumption , crystal

clocks are used for all timing requirements, ar~

ad complementary metal oxide

semiconductor (CMOS) logic is used in all digital and memory sections.

Laser Diodes and Trigger Packs

The hea rt of the laser transmitter is a laser diode module containing four laser diodes. The. quad laser sources are fabricated as two

sepa rate packages with two laser diodes in each package . Each dual pack

is a thin rectangular metal package with two laser diodes mounted at one

end. A square glass fiber optic is attached to the face of each diode

to provide optical coupling from the lasers to the source exit aperture

at the opposite end. The optic tube s are secured flush to one surface

of the metal package . Thus, when two dual packs are placed face to face,

the four radiating ends of the optic tubes are juxtaposed to form a square

array (Fi gure 9). Fiber coupling the laser diodes to a common radiating

plane ensures that the laser light is mixed sufficiently to eliminate the

holes and hot spots normally present in the raw laser emissions. Holes

and spots are a frequent problem with laser simulators that do not use

fiber optic coupling . The assembly of these dual packages is described

in detail in Appendix E.

Dual laser pack

Beam A

- Beain B

Fiber tubes

Onal

laser pack

Bears C

a n D -

Figure 9. Fiber optic tube configuration .

12

- - - - - - - -~~~~- -~~~~~~~~~ - - - S - - - - - -
The laser diodes themselves are single , heterojunction GaAs injection diodes manufactured by Laser Diode Laboratories, incJ The

light emitted by each diode has a peak power of approximately 7 watts

and a peak spectral irradi ance in the infrared (IR) region at 904 nanometers. Detailed specifications of the diodes are given i.i Appendix E.

Each laser diode is interfaced directly to a drive circuit consisting of a quad trigger pack . This arrangement allows each diode to be

pulsed a maximum of four times without the need to recharge the circuit.

Therefore , the pulse train in a complete firing cycle is accomplished

without a recharge of the drive circuits after each pulse. Figure 10

shows the schematic diagram for one quad trigger pack.

Collimating Lens

After the output of the diodes is brought to a common radiating

plane by fiber optics, a collecting and collimating lens is used to

project the beam pattern from the source plane. The laser light is

collected and collimated by a 2-inch compound lens (focal length of 2

inches). The lens is defocused to provide the four—beam overlap area

shown in Figure 11. The square shape is achieved because the light is

emitted through the square fiber optics. The overlap area has a cross

shape; the center of the cross contains all four laser beams and the

arms of the cross contain combinations of two laser beams. Appendix F

contains a more detailed discussion of the lens optics.

Be am Geometry

Each laser shot is scored as either a hit, a near-miss (suppression),

or a miss, independent of computer control. This scoring requires that

the beam pattern have certain properties to provide for the accurate and

realistic scoring of hits and near-misses. Figure 11 shows the configuration of the beam pattern projected downrange. The letters in each segment of the pattern show the individual beams and the beam overlap. The

overlap of the four beams (A, B, C, D) illuminates an area approximately

2 feet square; this is considered the hit zone. The hit zone is surrounded by a larger area, approximately 10 feet square, that is considered

the near—miss zone. The scoring electronics in the helmet receiver can

decode this beam pattern (i.e., determine which beams are illuminating

the target) and thus determine whether a hit or near—miss occurred and

the direction of the near—miss. (The “Laser Receiver” section discusses

the scoring logic in more detail.)

1

Commercial names are used only in the interest of precision in reporting. Their use does not constitute endorsement by the Army Research

Institute or the Army.

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C—D Overlap

4

Figure 11. Overlapping beam-pattern configuration .

15

• -- —-- — - - - - - -— --— - -- - —-— ~~ - -----—--- -- r - -- -• .•— — ----- - -—-- — - -

k
Laser emissions are IR light beams that increase in size as a

function of the distance from the source . Therefore , for a laser to

maintain some fidelity with live fire , the size of the beam must be controlled so that it does not increase appreciably as a function of ingreasing range. This control is achieved by manipulating the effective

width of the beams projected by the laser diodes . Effective beam width

is defined by the minimum amount of laser energy required to activate

the detector.

Figure 12 shows conceptually how the width of a single beam increases as a function of range while the effective beam width stays

constant. In the LES, the power distribution across the fiber optic

tubes is Gaussian in shape; that is, the middle of the fiber tube emits

a higher energy density than the edges. By defocusing the collimating

lens, a blurring effect is produced. This effect tends to exaggerate

the power distribution curve by letting the hi gher energy in the middle

pass undisturbed and blurring (decreasing the energy density) only the

edges.

The net effect is that , as the beam propagates downrange and the

energy is distributed over a larger area , the energy in the beam ’s

edges starts to f all below the detector ’s sensitivity level. Therefore, although the laser beam is growing , the energy in the expanding

edges is too weak to activate the detector. Therefore, the higher

energy density toward the center of the beam becomes the “ effective”

beam size. This pattern is symbolized by the area between the parallel

lines in Figure 12. The effect for four beams is comparable to the

case illustrated . The result, then, is an effective width of the four

overlapping beams that does not increase substantially as a function

of range.

Transmitter/He lmet Data Link -

To complete the onboard data collection capability of the system ,

it is necessary to record the total number of “ shots” fired and the

times they were fired. This information is used to determine the number of “misses” and also for diagnosis of system malfunctions.

A small GaAs LED mounted on the laser transmitter is used to

transmit round-count information to the shooter ’s own helmet. -This

technique eliminates the need for memory components in the laser transmitter unit and avoids the use of a cable connecting the rifle and the

man.

The LED is positioned so that it faces back toward the helmet.

When the laser transmitter is activated , the sync and address pulses

activate the LED. The light pulse from the LED is detected by a sensor

mounted on the helmet. When the receiver detects its own identification

code , this information is stored in memory as the round count. Because

16 

-• - - — — - • -
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~~ uIl(,s 

- UN 7

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Figure 12. Range invariant beam—size concept. 17

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--• ~~~~~ -- - _ _

- --- -- -- - - - - - 5- - — — — -5--—-— 5 ________
beam-pattern information is not transmitted by the LED, a player cannot possibly score a hit on himself.

Power

Two power sources are used in the laser transmitter: One supplies

voltage to the logic module and the other powers the laser diodes. The

CMOS logic has a very small current drain and a wide operating range ,

thus making the logic power requirements relatively small between 9 to

15 VDC . The logic modules are powered by mercury Duracel batteries

producing a terminal voltage of 11.2 VDC and a capability of 250 mi lliampere—hours of operation.

Carbon zinc batteries are used to power the quad laser pack; three

of these batteries are connected in series to supply 67.5 VDC to the

diodes.

The batteries, contained in the laser transmitter housing (Figure

7), weigh approximately 3.5 ounces, combined. Field testing !ndicates

that the power system will provide for at least 8 hours of operation

and at least 30,000 rounds. Appendix G contains more detailed information on the power supply.

Transmitter Housing and Mounti~9~

The housing for the laser transmitter is a tubular structure made

of die-cast aluminum. The housing and clamp assembly are j ig-bored to

provide the required alignment accuracy and stability. The transmitter

mount is designed to provide a rigid support that will not loosen with

heat or vibration. Rotation of the transmitter is prevented by the

machined keyway in the rear of the housing.

The electronic components, batteries, laser diodes, and drivers

are packaged in machined modules to facilitate permanent alignment and

minimize shock damage. The optical module is supported by two rings

in the housing for rigidity.

The transmitter is clamped to the slipring at the base of the

carrying handle on the M-l6. The weight of the transmitter is centered near the pivot point of the weapon ; therefore, it does not seriously affect the weapon ’s balance. The mounted device requires no

modifications of the rifle and does not interfere with the weapon’s

conventional sights.

18
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1 -- 5--- - -—- - — - — - - - • - - - - - - - _ _ _ ___ _ _ ____.____ --
Laser Receiver

The helmet-mounted laser receiver is shown in Figure 13. Sensors

and electronics are mounted on or in the helmet so as to equalize weight

distribution and eliminate exposed parts or cabling. The helmet receiver package consists of the following:

1. Six detectors are mounted on a band around the circumference

of the helmet liner. The wiring is contained in the band

and, together, the detectors provide for 3600 coverage.

2. The control, scoring, and memory electronics are mounted on

a logic board that fits snugly inside the helmet between the

webbing and the top of the helmet.

3. Small audio hit indicators are mounted inside the helmet above

the right and left ears.

4. The batteries for the power supply are housed in two metal

containers on either side of the helmet.

The receiver block diagram is shown in Figure 14. The timing and

control logic remains in an idle state until activated by a laser sync

pulse. When the detector receives a sync pulse, the threshold module

activates the timing and control logic. The timing and control logic in

turn enables the scoring logic and, together, they decode the laser message and store the data in memory. In normal operational use , the appropriate audio alarm in the helmet is activated when a hit or a nearmiss is scored. If real—time visual display of hits and near-misses is

desired , such as in a test situation , external control lines can be connected to the scoring logic for this purpose.

When the total message has been received and stored, the timing and

control,- logic resets itself to the idle state. External control lines

are present in the memory section for dumping memory (into a computer or

teletype) and for checking the memory circuits for proper operation.

The externa l lines also control the output shift register. This register

reads the memory and shifts 32 bits of information to the interface

devi ce .

Detector

Figure 15 shows a closeup of a laser detector mounted on the helmet

band . The detector/amplifier/threshold housing is made of die-cast aluminum and anodized green. An interference filter attached to the front of

the detector/amplifier case limits the wavelength of the ambient light

incident on the detector.

21
22

V 

—
Each detector is a silicon photodiode with a field of view of 60°;

six detectors are located at equal intervals around the helmet band.

Combined, the detectors provide for 360° coverage of the target. The

sensitive surface of the detector is 1 square centimeter and the peak

sensitivity is at 905 nanometers. Appendix H discusses in detail the

signal—to—noise ratio analysis for the filter and detector.

Timing and Control Logic

The timing and control logic contains a crystal clock, divide-down

counters, and windowing circuitry for receiving the beams and control—

ling the memory. The logic circuit is interfaced to the laser detector

through a variable—threshold amplifier. The output of the threshold

amplifier is tied to the master start portion of the logic circuitry.

When a laser sync pulse is received, the master start enables the

windowing circuitry to begin looking for the identification pulse. The

windowing circuitry scans all 32 identification timeslots and generates

a valid message signal if one and only one identification pulse is received. If no identification pulse is received , the logic interprets

the original sync pulse as having been noise. If twO or more identification pulses are received, neither one is accepted, because- (a) there

is either too much noise being externally generated or (b) two conflicting messages are being received.

In any case, if a valid identification pulse is not received , the

control logic resets the detector to the idle state and awaits a new

sync pulse . If a valid identification pulse is received in one of the

32 timeslots, the identification pulse is latched into a holding register and the beam-pattern decoding circuits are activated.

The beam—pattern pulses that are received are also latched into

a holding register. The identification and beam-pattern information

is held in the registers until the scoring -logic has been activated.

The scoring logic decodes the beam pattern in terms of hit and nearmiss scores and deposits the score in a memory location along with the

identification of the shooter and the time .

The time information comes from a free-running counter that op—

erates off of the crystal clock. The real-time clock can be reset by

external control lines. Appendix I shows the logic flow chart for the

laser receiver.

Scoring Logic

The scoring logic is activated when a complete laser message has

been received and placed into the holding registers . As mentioned

earlier , the score is determined by the beams that are detected . If

all four beams are detected , the logic scores a hit and activates the

23
audio alarm. If only two beams are received, the scoring logic registers a near—miss and activates the appropriate near—miss alarm.

Table 1

Scoring Logic for Beam Pattern

Beams Near—miss direction Hit

A - Low to the right

A+B Low

B Low to the left

B+C Left

C High to the left

C + D High

D High to the right

A+D Right

A+B+C+D Kill

(A+B+ D) Kill

(A+B+C) Kill .

(B + C -I- D) Kill

(A+C+D) - Kill

Refer to Figure 11 and Table 1. to see how v~

arious portions of the

beam pattern are scored. For reference purposes, the beams from the

four laser diodes are designated A , B, C, and D. The letters in each

segment of the pattern (Figure 11) show the beams and the beam overlap.

Inspection of Table 1 shows that hits as well as near—miss and direction

of near-miss can be determined by the beam overlap. Overlap of all four

beams is defined as a target hit, and a target hit can occur only if the

center square is illuminated. Logically , however, any combination of

three beams is also scored as a hit because these combinations cannot

occur unless the “bullet” is on the center of the target. The absence

of a complete beam pattern in these cases can result only from the loss

of one or more beams because of scintillation , partial target obscuration, etc.

As the table shows, direction of a near-miss can be determined

easily . For example , if the target is illuminated by beam A alone, the

miss is low and to the right. This conclusion may be somewhat confusing

because, in the pattern shown in Figure 11, the area illuminated by

beam A alone is above and to the left of the hit zone. However, if the

target is illuminated in area A only, the bullet is low and to the right

of the target, from the point of view of the shooter.

24 

5--- - - - - - - ----- -. -__- ~~~~~ —- -______
After the beam pattern has been scored , the holding register containing time , identification, and beam-pattern information is strobed

into memory to await output through the memory interface into the corn—

,puter or teletype.

Memory

The target-carried memory provides the capability for recording

data whenever an on—line computer interface is not feasible or not desired. The LES memory consists of off—the—shelf large-scale integration (LSI) circuits . These LSI chips were developed for microprocessor

use where considerations of high-density storage , reliability, low

power, and portability were paramount; a common application is in pocket

and desk calculators. In the LES , they are used to provide programmable

memory space for recording time-tagged identification and event data.

They permi t immediate postexperiment data readout by direct interface

into a teletypewriter or Teletype lines leading into a computer.

The helmet-mounted memory contains 25,600 bits and can record 1,024

time—tagged messages. The time bits can cover an 8-hour run at 1—second

resolution . The memory is wired into shift registers that format the

dat, output into standard ASCII code . This code makes dumping the data

easy and sakes the data compatible with many devices such as Teletype,

Teletype paper punch, telephone modems, ASCII floppy disks, and other

computer interfaces. Appendix J discusses the memory interface in

detail.

Real-time Display Device

The receiver contains a connector for external control lines that

interface with a real-time information display . The receiver is used

for laser ze roing and test purposes to provide the firer with immediate

feedback of information on hits and directions of near-misses. A visual

display panel contains lights that correspond to the beam pattern illuminating the target. In addition, the display contains a sonalert

that generates an audible tone appropriate to a hit, near-miss, or miss.

Appendix K discusses the LES display device in more detail.

Audio Hit Indicator

A player who has been illuminated by one or more laser pulses is

immediately informed whether he/she has been hit or near-missed . Two

audio alarms , one mounted on each side of the helmet, provide this information. Each alarm emits a single tone , and the scoring logic gates

the appropriate alarm on to indicate a hit or near-miss.

25

-5 •
The left alarm is keyed on for 1 second to indicate a near-miss

to the left. The right alarm is keyed on for 1 second to indicate a

near-miss to the right. Both alarms are keyed on for 1 second to indicate a high or low near—miss. When a hit is recorded , both alarms

are keyed on and remain on until they are manually reset by the player.

• Receiver Power

Two power sources are required for the receiver——one for the logic

and detector amplifier supply , and the other for the detector bias supply. Mallory mercury batteries (TR 115) are used for both purposes.

Four batteries are wired in series to supply approximately 28 volts

to the detector bias supply. Four other batteries are wired in parallel to supply approximately 7 volts at 50 milliamperes to the logic

and detector amplifiers. Further details of the receiver power supply

are given in Appendix G.

Receiver Packaging and Mounting

Figure 16 shows how the receiver electronics, detectors, and power

supply are mounted in the helmet liner and on the helmet band. The helmet band is made of Fiberglas formed to fit down over the helmet and

seat on the base. The detectors are individually housed and placed at

equal intervals on the band. The two battery supplies are also individually housed on opposite sides of the band. With the helmet liner

on, the batteries are located near the player’s ears.

The audio hit indicators are mounted on the inside surface of the

helmet, one next to each earphone. The logic board , containing the

memory chips and the control and scoring logic, is mounted in the dome

on the inside of the helme t (see Figure 17). The logic board is secured in place by a metal plate, and connections to the board are made

through a hole in the plate. The receiver components add approximately

2 pounds to the weight of the helmet liner, which is about equal to

the weight of the regular steel “pot.”

Computer

The prototype LES operating in a st~

and-alone mode can collect and

record 1,024 time-tagged messages. These data , stored in the playercarried memory module, can be read out to either a standard ASCII

Teletype or a small , multipurpose computer such as the DEC PDP-8/E .

The memory electronics and memory interface module can be programed

to buffer and to encode the data so that the data will be compatible

with most small computer systems. -

26

-5 •
I

~~~~~~~~~~~~~~~ t--

I
- -

Foam padding

Logic board Metal plate

I/O plug I/O cable to band

Helmet liner

Left audio Right audio alarm

Helmet front view cutaway

Sensors

Battery box Battery box

Helmet top view

Figure 17. Receiver electronics configuration.

28
With this capability , ~ multigun s?stem could be developed to collect and record real-time casualty assesssent -iita, including target !

shooter identification , during two-sided, simulated combat exercises.

Afte r an exercise , the data from all the memory modules could be read

into an onsite computer system for data reduction and analysis, or the

data could be recorded on magnetic or paper tape for later reduction

and analysis.

29
-.

APPENDIX A

LES SPECIFICATIONS

Performance Characteristi cs

Firing modes Semiautozna~

-ic , fully

automatic

Firing rate Exceeds cyclic rate of fire

of all automatic weapons

Trigger mechanism Acoustical transducer actuated by blank round triggers

laser

Maximum effective range 350 meters

Onboard memory 25 ,000 bits of memory; total

of 1,024 messages

Playe r identification 32 identification slots

Electronic and Optical Parameters

Laser source GaAs laser diode

Peak power output 7 watts

Peak emission wavelength 905 nanometers

Peak forward current 30 amperes

Pulse width 100 nanoseconds

Message repetition frequency 12.5 hertz

Beam divergence 5 milliradians

Output format Time -modulated pulse code

Detector type - PIN photodiode

Detector field of view 60° inclusive

Solar background rejection Operates in full sunlight

‘-5-, - - • •.- -

~~~. - 5—

31 

_ _ _

S - -

~ —
Physical Par ameters

Transmitter

Length 6.5 inches

Diameter 2 inches

Weigh t 2 pounds

Detector-helmet band assembly

Diameter 9 inche s

Weight 1 pound

Helmet, logic, memory assembly

Fits inside helmet

Weight 1 pound

32

S ___

_

_5 

1

~~~~
APPENDIX B

LASER SAFETY

The use of any laser device presents the possibility that personnel

may be exposed to potentially hazardous radiation from these devices.

The radiation hazard is in the form of ocular damage that can occur from

staring into the laser transmitter. Laser energy entering the eye can

be focused by the lens to an extremely high energy density. The resultant temperature can be great enough to cause a permanent burn spot on

the retina which can lead to partial or total blindness.

The following information on the eye safety of the LES system is

based on engineering estimates. The LES will be submitted to the U.S.

Army Environmental Hygiene Agency for a forma l radiation protection study - - to determine if the system meets the eye safety standards set by the Surgeon General (given in Army Regulation AR 40-46 , “Control of Health Hazards from Lasers and Other High Intensity Optical Sources”) and the Environmental Hygiene Agency (given in Army Technical Bulletin TB MED 279,

“Control of Hazards to Health from Laser Radiation ,” May 30 , 1975).

• The emitted laser beam is divergent outside the exit aperture;

there fore , the greatest radiant exposure occurs at the exit aperture .

The calculations that follow will assume this worst—case eye position

(at the exit aperture) and long-term focusing directly into the laser

device.

The calculations, nomenclature , and symbols will follow the Department of the Army TB MED 279. The maximum firing rate for the LES is 750

rounds per minute or 12.5 rounds per second. A 20—shot burst in 1.6 seconds is the maximum continuous firing interval, assuming a standard M-l6

magazine . There are six laser pulses emitted for each round expended

(see Figure B—l) . _ - -

SYNC ID

1 [1 [1 -

~ ÷l0~~ sec

28W

4 

)

_- JELrLrLFL

400 jisec ~ I 20 iisec

Figure B-i. Single-round pulse output diagram.

•_ _--- _

~

- -— _
The first two pulses are a synchronization (sync) and an identif ication (ID) pulse consisting of the simultaneous firing of all four diodes and having ‘28 watts of power each. The last four pulses are the

pattern pulses of 7 watts each. All pulses are l0~~ seconds in width

(Tp) . The maximum power available from each diode is 7 watts, but the

LES is operated at a lower operating point and the measured diode output is 5 watts. However, for safety calculations the 7—watt value is

used. -

The radiant energy , Qp, in the sync and ID pulse is

x T

~ 

where •.

~ = 28 Watts

and = 1O

~~ 

sec.

= 28W x 1O~ Sec

= 28 x 1O

~~ 

J .

The radiant energy in a pattern pulse is

Q

~ (pattern) = x T

~ 

where = 7 Watts

= 1O

~~ 

sec.

Q

~ 

(pattern ) ~~7W x 1O

~~ 

sec

= 7 x 10

~ 

J

The time-averaged radiant power over the 20-round burst is

~avg. 

20 (rounds ) x ‘[2x Q

~ 

(sync or ID ) + 4 x Q

~ 

(pattern)] (W sect 10~~

round 1.6 sec

avg. 

20 x [ex 28~

+(4 x 7i1 W (iO~~)

avg. 

1.05 x 10~~ W . j

34

I •— 

_ -

_ _ .——— _ -•——_-._ - _ •• . -~~~~ — —
The exit aperture is 5lm in diameter , which provides an exit area ,

A , of 20.25 cm2. The time-averaged beam-power density over the exit

aperture gives a poweL average ,

E

avg . = 

avg ./A

= 1.05 x 10

~~ 

W

20.25

= 5.2 x io 6 

~~cm

2 .

The averaged peak radiant exposure is

~~vg. = Q

~ 

(sync or ID),A

= 28 x J

-20.25 cm2

a 1.4 x l0~

7

J/ cm2

The three areas to evaluate in laser safety are (a) single-pulse

radiant exposure, (b) average radiant exposure, and (c) exposure limit

reduction as a result of the pulse repetition frequency.

Single-Pulse Radiant Exposure -

~

standard (single pulse ) = 1.25 x io 6 J/2

LES lT

avg 1.4 x 10~ J/~~2

Safety Margin a 1.25 x ~~~

- 1.4 x 10~~ J/~~2

• 8.9.

35
Average Radiant Exposure

Estandard 2.5 x o

~ 

W/cm2

LES !

av g . = 5.2 x io— 6 W/cm2

Safety Margin = 2.5 x 1O 3 W /cm2

5.2 x io_ 6 W /cm2

= 481 .

Exposure Limit Reduction as a Result of the Pulse Repetition Frequency (PRF)

The safety reduction factor resulting from PRF is .06. Therefore,

Safety Margin = .06 (H standard ) -

~avg . LES -

- = .06 (1.25 x 1o 6) = .534 .

1.4 x 10~~

The safety margin of .534 is not eye safe . However, the figures

assume that all the repetitive pulses are of the same amplitude as the

sync and ID pulses. The pattern pulses are actually only one fourth

that value . By averaging the peak power and then calculating, the

safety margin is as follows:

Peak power average a (2 x 28 x 10

~~ )+ (4 x 7 x ~Ø 7) J

6 (20.25) cm2

=7x 1 0

~

8 J/cm2 .

Safety margin = .06 (1.25 x 1O~ j

7 x10 8

= 1.1.

The 1.1 margin is eye safe .

36 

:. )
The conclusions that can be drawn are that the LES system will be

eye safe at any range beyond 3 m from the exit aperture and probably

will be eye safe between the exit aperture and a range of 3 m.

37
APPENDIX C

ACOUSTICAL TRANSDUCER

The laser transmitter uses a small dynamic earphone made by Allied

Radio (No . 33174) as an acoustic transducer to detect when a live or

blank round is fired by the weapon . The transducer is mounted in a

small insulated compartment in the transmitter clamp assembly (Fi gure

C—i) and is surrounded on all sides by a thin layer of foam insulation.

This insulation helps isolate the transducer from the weapon, thus reducing the possibility of false triggering because of mechanical vibrations whei-i a round is chambered.

An audio transducer is used because it has some advantages over a

pressure transducer. The frequency response of the audio transducer is

in the low range ; therefore , it attenuates the high—f requency signals

from the bolt returning in the chamber and ensures a better signal-tonoise ratio. The audio transducer also does not saturate on the mechanical vibrations or gas pressure . Since the transducer does not go into

saturation , any-amplitude difference between the blank firing signal and

the bolt returning can be better discriminated. Finally , the audio transducer moves in only one plane . It is mounted for movement In the vertical

plane, thus eliminating the stronger shocks that occur in the longitudinal and transverse planes.

In normal operation , - the laser transmitter is clamped to the slipring on the M-l6 in such a way that the coupling chamber and transducer

compartment are close to a gas port near the base of~ the carrying handle.

This gas port is actually a star-shaped hole through which the gas tube

enters the cylinder (Figure C—2) . Inside the cylinder, the gas tube is

coupled with the bolt carrier key; when the weapon is fired , the pressurized gas in the tube causes the bolt carrier to move to the rear.

The star hole allows a small portion of the gas used to push the bolt

carrier to escape out over the slipring. When the laser transmitter is

clamped to the slipring, the coupling chamber forms a tight fit around

the star hole. Thus the pressure wave emerging from the star hole is

forced into the coupling chamber, where it is detected by the acoustic

transducer.

The signal generated by the transducer is fed to an impedance

matching transformer. A fixed resistai

~

ce of 3.3 ohms is shunted across

the transducer to provide a uniform fixed load for the impedance matching transformer. The output of the transformer is interfaced to the

transmitter logic module by a single transistor.

Measurements made of the output signals from the transducer produced

when a blank round was fired and when the bolt was allowed to slam home

on an empty chambe r showed a signal-to-noise ratio of 4:1. The signal

level produced by a -blank round was 2 volts peak to peak and .5 volt

bolt peak to peak for the bolt return only.

39 _ 

_

- _ S -. _ -~
Coupling _— —

chamber

Acoustical

transducer

compartment

Figure C-i. View of coupling chamber.

Handle

Star hole

0 Barrel

Slipring

Figure C-2. Cutaway view of gun at slipring.

• 

. 40

5 . 5 — •
APPENDIX D

LASER TRANSMITTER LOGIC FILM CHART

4.)

U

‘

~~~~~~

— 

41

- _ _ • - ~~~~~~~~~~~ -

_ -_ _ --_ _ _ - _ _ _ - - _ --• _ _ _— _ - - _ - - -- _ _ -- --

__ 

_
APPENDIX E

LASER PACKAGE

Laser and Fiber Optic Package Assembly

The laser package must fulfill several requirements. Basically ,

it must hold lasers rigidly in a radio frequency (RF ) shielded enclosure , allow for efficient low—impedance electrical input , permit good

heat conduction from the laser chips to the outside heat sink , and

provide optical coupling from the lasers to the source exit aperture .

So that the light out of the fibers will be uniform over this cross

section , the fibers must be long enough for optical integration to

occur.

- - -. The LES laser transmitter uses four laser diodes assembled in dual

laser packages. Each of the dual packs is a thin , rectangular , metal

package with pins along each of the long sides. Al]. pins are grounded

to the case for shielding purposes except the two central pins attached

to the p-sides of the lasers. The laser diodes themselves are mounted

on copper blocks that have a step machined across the face to allow at—

tachment of the fiber optic.

The fibers are made by drawing conventional glass fibers . Special

high-index optical glass is first machined and then drawn into a thin

thread of glass with a .010—inch-square cross section . The fiber sections selected for use are the same size within 100 millionths of an

inch. The fibers are scribed and broken to 1-inch lengths . One end

of each fiber segment is ground flat and polished .

The previously formed fibers are held in a special fixture that has

precision adjustments in 6 degrees of freedom , and the fibers are positioned in the laser package under a microscope. The polished end is

butted against the laser diode. The shaft of the fiber is positioned

in the same plane as the top cover of the laser package and is offset

to one side of the top cover’s longitudinal center line. A small amount

of adhesive is placed at the fiber—laser interface and cured . A second

fiber is attached similarly. A properly slotted cover is placed on the

package and a separation of proper thickness is placed between the fibers.

The fibers are held in precise position and epoxied in place. The excess

fibers are scribed and broken off. The fiber ends are then ground flush

with the package end and polished.

These packages form an extremely rugged optical source. Mounted in

the laser transmitter , they have undergone hundreds of blank firings on

the M-16 rifle . No failures because of shock or normal operation in the

laser gun have been experienced to date.

____________ 

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Laser Diode Specifications

1

The laser diodes used in the LES transmitter are LD-33 GaAs injection diodes that emit coherent infrared radiation . The diode is built

in a heterojunction structure consisting of three distinct layers :

N-type GaAs, P-type GaAs, and P-type GaAlAs. Recombination occurs in

the immediate vicinity of the GaAs P-type region . The heterojunction

formed at the interface of the P—type GaAs and P-type GaAlAs confines

the injected carriers and also reduces reabsorption . As a result of

this , threshold is reduced and power efficiency correspondingly increased . The radiant power output is proportional to the forward curren t and the spectrum is in the region of the peak sensitivity of the

S-i photocathode surface and of silicon photodetectors .

The device is capped with a nonabsorbing plastic making it mechanically rugged . The package includes a 4-40 screw stud that is the negative terminal of the diode and can be used for mounting to a grounded

heat sink . The positive terminal is a lead parallel to the plane of

the header. The output radiation is emitted along the axis of the stud .

1 Technical specifications provided by Laser Diode Laboratories, Inc.,

Metuchen , N .J. 08840.

44

-•-.•- .•...--

~

--• ---— - •~~ -.-• - --~~~~~~~~--•- —----- -- —---— -- -5-- - - 5 S -- - - --- -
APPENDIX F

LENS OPTICS

The LES uses an optics system consisting of a condensing doublet

lens that acts like a simple projector lens. The quad laser stack

is placed inside the focal point and the lens projects a blurred pattern down the field. The emitting radiation is collimated but never

is focused ; therefore, the beam is always diverging (see Figure F-i).

The divergence is given by the radiating source size over the focal

length :

= Ds where Ds is a source size of .020 inch

F.L. and F.L. = 2 inches.

= .02

2

= .010 or 10 millirads.

~~~~~~FLI

Figure F-l. Beam geometry.

The overlap areas in the beam pattern are created because of the

physical proximity of the four fiber sources and the defocusing of the

lens. The blurring effect makes each source appear larger than it is,

resulting in an overlap of the beams in the pattern projected downrange .

As the pattern increases in size as a function of range, the hit zone,

or area of overlap, remains relatively constant in size because the

power distribution at the edges of each beam drops below sensor threshold. Thus, as the beam diverges, the power distribution at the edges

decreases sufficiently to keep the effective overlap area relatively

constant in size.

• 45 

— - ---- —5- — p - — - - -—~~~~~~ - - — —
APPENDIX~G

POWE R

Laser Transmitter

The LES system laser transmitter requires a small lightweight

power source capable of furnishing enough power for 8 hours of continuous operation and at least 10,000 rounds of blank firing. In addition, the power source must be portable. The only solution to the

above requirement is batteries.

The present laser transmitter mechanical design includes a location

for batteries at the rear of the main tube assembly (see Figure G—l).

Approximately 4.5 cubic inches of space are available. A simple , easily

removable end cap is utilized for ease of battery replacement. Spring

tension provided by the end cap assures good electrical contact with the

batteries.

Battery Specifications

There are two different types of batteries used in the LES laser

transmitter. One type of battery supplies power to the logic module .

The other type of battery supplies the high voltage (67.5 volts DC) to

the laser module assembly.

Logic Module Battery

One Mallory PR 118 mercury Duracel battery is used to power the

logic module. The terminal voltage of the battery is 11.2 volts DC

with a service capability of 250 milliampe re hours. The suggested load

current range is 0—50 milliamperes. The battery weight is 1.15 ounces

and requires .60 cubic inch space.

Laser Module Assembly Battery

Three Eveready 505 carbon zinc batteries are used to power the

laser module assembly. The terminal voltage of the battery is 22.5

volts. Three of these batteries are connected in series to supply

67.5 volts DC to the laser module assembly. The suggested load current

range is 0-1.5 milliamperes. The battery weight is .8 ounces. The

volume is .74 cubic inch.

_______ 

-

________

4. 5 5 5
.-1

.

~~~~~

3 ___________ 

1

• 

- I 

________

I ‘

~~~ I w e ~~~~~~~~~~~~ .

~~~~ E.

~~~4 I E~~ Q4 ~~~ 4.)

____

.i4j ] U

ii £

I

/

48
Battery Life

Extensive field testing has been done using the above specified

batteries. Test data indicate these batteries will power the system

in excess of 8 hours and provide at least 30,000 rounds of blank firing.

Laser Receiver

The LES system laser receiver requires a small lightweight power source capable of supplying enough power for at least 8 hours of continuous operation . The power source must be portable and compatible

with the voltage and current requirements of the laser detectors and

logic module .

The present helmet configuration is in the form of an electronics

band assembly . The band assembly fits over the helmet liner and contains space for six laser sensors and two separate battery boxes. Each

battery box will accept four batteries. The top covers of the battery

box are removable for easy battery replacement. The battery boxes are - made of aluminum and are 3-1/8 - inches long, 1—1/2 inches high, and 3/4

inch thick.

Batte ry Specifications

One type of battery satisfies all of the power requirements of the

helmet receiver. The battery used is a Mallory Duracel mercury battery

type PR li5R. The terminal voltage of the battery is 6.75 volts with a

service capacity of 250 milliainpere hours. The suggested load current

range is 0-20 milliamperes . The battery weighs .73 ounce and requires

approximately .44 cubic inch of space . The battery is 1.32 inches long

and .660 inch in diameter.

Eight of these batteries are used to supply power to the receiver . One battery pack contains four batteries wired in series to supply the

high voltage bias required by the laser detectors. The other battery

pack contains four batteries wired in parallel. The parallel combination is required to supply the current requirements of the detector amplifiers and the logic module.

Figure G—2 shows the battery schematic.

Battery Life

Extensive field testing has been done using the above specific battery. Test data indicate that the batteries used to supply power to the

detector amplifiers and logic module will last for at least 12 hours of

continuous operation.

49
The batteries used to supply bias voltage for the sensors will last

several days. The current drain required from these batteries is very

low, resulting in longer life.

33.75 V bias to

~ Sensors

1+IL~ Battery Box —* I

~~~~~ I +6.75 V to Logic

Battery Box —~~ ±Ltt~~1t t ,

— — — — — — — _I ~ Common

Note. All batteries are Mallory PR ll5R, 6.75 volts.

Figure G-2. Power supply schematic.

II

50 

_ -~~ . — •.-_—___—.u——.-..5, —
APPENDIX H

SYSTEM EQUATION AND SIGNAL-TO-NOISE RATIO ANALYSIS

A physical model of the system is shown in Figure H-i. From

Figure H—i , the power density (lo) is a function of the initial power

(P0), the solid angle ~

0b ’

~~’ and the transmission of the collimating

lens (Tt).

I =PT

o ot , ______ 

Where 0

b is in sterads

- 0b . 2 radian) = 0

b sterads.

The received laser power (Ir) is a function of the detector area

(Ar), the range (R) , the optical efficiency of the atmosphere (a), and - the transmission of the laser filter (Tr).

I =1 A r o r —aR

e T —i-— r

R

Substituting P P

Ot for gives

I =P A r o r -aR

—— e PT.r t

R

The maximum theoretical power of the laser diodes is 7 watts. However, only 5 watts have been measured . Therefore, the 5—watt value (P0)

will be used to calculate the signal at 300 m (R).

The laser transmitter optics losses are estimated at 20% loss or

80% transmitted (Tt).

The receiver interference filter passes approximately 70% (Tr)

~

The beam spread is 10 milliradians ~

0b)- or the solid angle of the

beam is i0~~ sterads

The laser receiver’s active detection area is i. cm2 (A)

i i _ _____ •~~~~~~~~~~~~~~~~• . • •~~~~~~~~~~~ 

~~~~~

•

~~~~~~~~~~~~~~

_ __ _
4.) 4) a. ~

w

.~i 

H

.,.4 Ic 4)

loo

n.

C

~~~~~~~~~~~~~~~~~~~~~~~ ~

I~

l

A~~ Lf

~~

4, 0

w

i.~

~n .w iJ I.~~4.) 4.) 

- n n w 0

~ 1.) .1.) 

~~~~~~~

—

~

‘t

U)

I.’

a ~~~~~ .4:I

( flu

~

,I 

~ 

- w b s ~ ~~~ S n.o w o ~~~~~~~~~~~

‘u I. ~~~~~ ).

\.

4J () ~~ C) 

~q

.4 

C) 0)4) 

w o — 0) 1.) 0) .).) ~~~~~~ ~~w o w r4’ ~ r) ’O n.w

I 0)

cc 

c) ’e.i 

e

q.,

HO 

< 0 ~~~O

~

, 0)1W • o .

•01

4.1 0 .( 

H r-I E4

4) t__• 

4)

z U)

>1

1-1 

~~

e

.

~~

.4 

H

~~~,

e

H

‘

~~~

4) 4) 

w -$.~ ,0 00

Cl) 0)

0 4.1

1.1

0

1°

~~

~

c IW U)

1.1 1.)~~~~

p 

~~~

4J ,.

4 w i.

4l 4) 0. 

.

“ So

‘w e

- 

.~. 

)0

‘I 

~~~~~~~~~~~~

4) 4’ ‘4 1.1

L -- - 

52
The atmospheric attenuation coefficient (c C ) is dependent on two variables , which are the scattering coefficient (a) and the absorption coefficient (K). The equation for attenuation , assuming monochromatic

radiation , is

a = a + K.

The scattering and absorption coefficients depend or: molecular

actions (subscripted m) and aerosols (smoke , fog , mi~ t—— subsci:ipted a).

Therefore ,

00 + 0 m a

K=K + K m a

• and

c C =G +~~~ + K + K m a m a

Data for 0

m ’ 0a’ Km , and Ka at a sea level horizon tal path (wors t

case) for the GaAs wavelength are shown in Tables 11—1 and H-2.

Therefore , -

a = 2.09 x ~~~~ + 2.5 + 1 x i0 6 + .38 very hazy

= 2.88.

Theref0re, the incident power on the active surface at 300 m is:

I = P A~~~~aR 

T I P 5w r or r t 0

2 —4 A 1 cm = 10 in 0

b R 2 r

= 5w (i0)~~ ~~~~~~~~~~~~~~~~~~ : = 

2.88

l0~~ 3002

_ 5 

P

t~~~~

8

1.31 x 10 w e ‘ = • b

R 300in.

I

• 53

- .5- — ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ - . — — -- —. - -S____=.5________.___

___ -
Table H-l

Coefficient _____________ Climatic zone _____________

molecular Mid-latitude Mid-latitude Subarctic

km l Tropical summer winter win ter

a 1.89 x ~~~~ 1.93 x ~~~~ 2.09 x ~~~~ 2.21 x IO~~

K

m 

<10 6 <io _6 <io _6 

10 6

Table H-2

Aerosol coefficients _______________

Clear Hazy Very hazy

Coefficient 23 Km 5 Km 1 Km

K~~~ visibility visibility visibility

9 x 10 2 • 4.4 ~ l_o

~~ 2.5

K 1.52 x io_2 7.43 x 1.0~~ .38

5 54

j - - — -- --— --55- — 5 - —--——— - ———— —— —.. -- - ____
The current output (‘out) of the detector is equal to the inciden t

power (I

r~

) x the responsivity of the detector (R).

I = I x R - R = .5 amp/watt. out r S 5

= (1.31 x 10 5

w) (.5 amp/watt)

= 6.55 x 10 6 

amps

The output signal ~~~~~ from the amplifier is given by the input

current ( lout) x the transimpedarice of the amplifier (Rf).

S = I x R R = 30 x 10 ohms. out out f f

= 6.55 x iO 6 

amp x 30 x l0~ ohms

= 196 x 10 volts -

The measured noise in full sunlight is ~lOO x IO~~ volts. Therefore, at 300 m the signal—to—noise ratio is

Signal = 196

2.

Noise 100 - -

-— ___ _5-5- - -5-—— --- -~~~

-5
APPENDIX I

L14.SER RECEIVER FLOW (]4ART

-

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 

q

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

- 

~~

i !

~

1

NO In - PULSE -

BUFFER ID -

WAIT FOR - - BEAM PATTERN

SET ERROR 

-

NO -

NO BEAM

PATTERN -

TIME

DECODE

PATTERN

- i 

_____ 

_______
APPENDIX J

MEMORY INTERFACE DEVICE

The memory interface device serves the following functions :

1. Before the start of an exercise , it checks out the receiver

memory chips for proper operation ,

2. It zeroes the memory registers and puts them in a start mode,

thus resetting the internal clock and synchronizing all of

the receivers be ing used , and

3. After the operation , the device reads out the memory, formats

the data, and outputs the data to a computer , teletype , or •

other display device.

Figure J-l shows the block diagram for the interface device and

Figure J-2 shows the flow chart for the logic operations. The operator

selects one of three function modes-—memory checkout , zero and start,

or read memory. The timing and control circuit scans the operator function switches, activates the appropriate function , provides timing , and

makes the basic go/no—go decisions on the memory

5

checkout routine .

All data flow through the input register and are displayed on the

operator’s display. The data are also duplicated , split, and sent to

the memory checkout or the TTY formatter depending on the function selected. In the memory checkout routine , each of the memo ry chips is

exercised by placing successively a 0 and 1 into the bit registers to

determine that the electronics are functioning properly (see Figure 3—2).

If there is a malfunction in the memory, a no-go signal is displayed on

the panel and the routine is stopped.

In the readout mode , the timing and control logic places the data

directly into the TTY formatter, thus bypassing the checkout circuitry .

The formatter changes the data into ASC II code and outputs the data to

a 20-mA loop for Teletype display or computer processing.

. 

_ _
Cl)

IJJ

I-

.-fl-U.)

—J~~~

>-

.

0

_J

~

Cl,~

T -

~~

— ‘

~~~ 0) S u..

- 

— _ -

~~~~~~~~~~~~~~~~~~~~ ø~~~~~ .

~ - La.. ~~ 4) I— .0)

>- -4 0. . I— 0) - l— C)

00w

60

---5—- - - - - _____________________________________

- — - — 5-— —— —5--- -
[

WA IT

DISABLE TIME

~ EMOR YES PUT l’ s in if FF

CHEC KOU uno ~ PUT 0’s i n i f FF

1011 E NO

~~~~~~~~~~~~~~~~~

S _ SE TFF 

DONE

NO 

1100

Op

ST RT ACTIVATE LASER MSG - 52 ID IF FF1 .FF 2

25 ID IF FF1 .FF2

DUMP 

. 0 ID IF FF1 .FF~111

YES

ADOR ~

l

& KILL - ________________ 01 00K] YES

—1 

STROBE CS I

‘I, - 

~~~~ 9~

T

~F1 FF2

O1O1L 2

~ 18 If 

.1. ~~~~0111 G1

STROBE SHIFT

& ADDR1101~ - 

NO CHECKS

OK

i ooi t

~ - - YES

SHIFT OUT I 

- 

. 

LAST NO

ADDR

‘N. GO .

.-

.

‘ YES _______________

~~~~ ES _ _ _

OUTPUT 1 ‘NOP YES ~ NO I PULSE FE’ s

oooi c

~ - - I~~ARM F (, FE 001 1 I

NO 

[-RESET TIME - 

~ RESET FF

- RESET 

Fi~ ire J—2. Memory interface

DONE I

~ 

RESET KILL I

ADD _______ ()fll O .11

logic flow chart.

ADDR

NO 

‘

~

N

y

~~

’

~ 61

•1 

______ __

- - C ~~~S5- — —- - —

~~~~~ 

- - — - - - — — —
APPENDIX K

LES DISPLAY DEVICE

Purpose

The purpose of the LES system display is to provide the firer with

real—time information concerning hit and near—miss data generated by

the target electronics module .

In addition to providing visual indication of hit and near-miss

data , the display contains a sonalert that generates an audible tone

upon receipt of hit , near—miss (beam pattern) , or far-miss (no beam

pattern) data .

The display contains a mode switch for selection of either a threebeam -

~r four—beam kill. (See Figure K-i.) -

Functional Description

Input Circuitry. The input circuit to the display is designed to

operate over a long distance-—several kilometers if necessary——by means

of a single run of two conductor cables. The circuit is compatible

with a standard 20—milliampere Teletype loop and contains a 20-rn-A loop

source .

The input interface element is a Monsanto MCT2E optical isolator.

The optical isolator provides isolation between the decoding logic and

the incoming line , reducing the possibility of false data caused by a

noisy environ., ant.

TTY Decoder. The data format used by the display is the standard

ASCII (American Standard Code for Information Interchange ) seven-level

code . Data received by the display aru in serial form and must be converted to a parallel format before decoding . (See Figures K-2 and K-3

for the display device block diagram and flow chart.)

Serial—to—parallel conversion is accomplished by a single , universal , asynchronous receiver—transmitter (UART ) logic chip. The PART

accepts asynch~

:onous serial data consisting of a sync bi t, up to eight

data bits , an opt ional parity bit, and two stop bits . Bit weight is a

function of baud rate and is equol to 9 milliseconds in the present

system. The baud rate could be increased for faster data transfer if

necessary . A master reset switch is u3ed to reset the display to zero.

1:1- - 

-- ‘ ‘ ~~~~~~~~ ..

63 1 --•

~~~~~ — ~~- —~~~~~- 5-

L -—.— ----

~~~~~~~~~~~~~~~ 

_
Test Master (Top of Indicator

Lamp Rese t Display) Lamps

-L/

~

,

s o

Mode Switch —* Q e

Sonalert — —

~~

Sonalert

on/off ~~~~~~ off Q -

0 0

Data Input — 0 e 0

Power ______ /

Cord ______________

(I To +6V, -6V

~ Battery -

Figure K-i. Display device.

64

5- - ~—— -
Cl) 0

0. Li < 0. • 0. I— (

~

) —.; 

~~~~~~~

0 Cl, -4

‘

1 -

_ -

w

~~~

~~~~~~~~~~~ 

-1 - 

I

0 -

-

d ~

- (_) v w — - —

~~~~~-4

T _ -

_ - T

a- -a 00V.,

‘-4

~

J

~ U

65

-. . . - — .._•_,_ _., — - —- - ‘——— — — _

~

•

~

* — ~~~~~~~~~~~~~~~ ai.t.v ,rn-

~.~~S- sa.
START 

CHECK FOR DATA - 

A

DATA -

AVA IL

- YES

•ENABLE UART

READ & FIRE

SONALERT

-

~~1~

DECODE MESSAGE

READ

MODE

SW ITCH

~~~~~~~~~~~ T LIGHT K ILL 

ES <

TLIGHT 

~~~~~

KI LL 

ES 

1

_

~

iGHT NEA R MISS I

LAMP AND • LAMP AND - I’ AND DISABLE

DISABLE - DISABLE SONALERT

SONA LE RT - - SONA LERT L

dHH b

Figure K-3. Display device flow chart.

66
Data Decoder. The output of the PART consists of four parallel

thta lines. These data must be decoded into the proper format to drive

the hit-near-miss visible indicators. Decoding is accomplished by two

BCD to decimal decode r logic chips. The output of the BCD decoder is F fed to the mode switch.

Mode Select Switches. The display contains a single , two-position

rotary switch that enables the display to be used in “normal” or “test”

mode.

With the switch in the normal position , any three-beam combination ,

the presence of all four beams, or the presence of any two diagonal

beams will cause the center kill lamp to illuminate .

When the mode switch is placed in the test position , all four beams

must be present before the center kill lamp will illuminate.

In addi tion , when the switch is in the test mode, any two diagonal

beams received, will illuminate their respective lamps. This is the

only condition that will cause two indicator lamps to illuminate

simultaneously.

Indicator Lamps. After the incoming data have been decoded properly ,

they must be displayed to present a visual readout to the player. Incandescent lamps are used as the display medium . Lamps with a high degree

of brightness were selected so the display could~be utilized in bright

sunlight . To supply the current required by the lamp , a transistor

driver is required for each lamp. In addition , a test switch is available to ensure all lamps are operating . When the test switch is depressed, all lamps illuminate to indicate operating status.

Audible Indicator. Any time a command is received from the logic

module in the helmet, a sonalert in the display is. keyed on for .5 second.

This audible tone alerts the player that a message has been received by

the display . In addition , if the data line between the helmet and the

display becomes open for any reason , the sonalert will give a continuous

indication to alert the player that a problem exists. The sonalert can

be switched in and out of the circuit by means of a toggle switch located

on the side of the display chassis.

Power. Power for the display is supplied by a single, rechargeable ,

Nicad battery pack. Power requirements are +6 volts DC and -6 volts DC.

Current required varies as a function of the number of lamps illuminated

at any one time . When the lamp test switch is depressed , all lamps iiluminate at one time and the current required is 6.5 amperes. The logic

board draws 100 milliamperes at +6 volts DC and 15 milliamperes at -6

volts DC. Each indicator lamp draws .5 ampere at +6 volts DC.

67
Display Format. The display contains 13 indicator lamps arranged

in a square pattern (see Figure K-i). Individual lamps indicate which

beam or combination of beams illuminated the laser detector .

For example , if lamp ~ illuminates, this indicates only beam A

hit the detector and that a near-miss in the upper left-hand corner was

recorded. See Table K-i for the complete display format.

Table K-i

Display Logic Format -

Beams detected Mode switch Lamp illuminated Shot location

A * A High lef t

* A-B Overhead -

B * B High right

B+C * B-C Right

C * C Low right

C+D * C-D

D * D ~,, Low left

A+D * A-D - Left

A+C Test 1+3 - Kill

B+D Test 2+4 - Kill

A + B + D Test 1 Mid-high left

A + B + C Test 2 Mid-high right

B + C + D Test 3 - 

Mid-low right

A + C + D Test 4 Mid-low left

A+B+C+D Test 5 Kill

A+C Norma l 5 Kill

B+D ‘ Normal 5 Kill

A+B+D Normal 5 Kill

A+B+C Normal 5 Kill

B+C+D Normal 5 Kill

A+C+D Normal 5 Kill

A+B+C+D Normal 5 Kill

Construct ion

The display is constructed on an off-the-shelf Bud Chassis No. ACl43l.

The chassis dimensions are 17 x 17 x 4 inches. All of the decoding logic

and lamp drivers are mounted on a small board inside the chassis box. A

stand is permanently attached to maintain the display in an upright

position . -

68
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1 US WAC Cu & ScIs, Ft McClellan , ATTN: Tog Dir I USA Intelligence Ctr & Sch, Ft Huachuca, ATIN: ATSI—CTS—OR

1 USA Quart ermaster Sch , Ft Lee, ATTN: ATSM-TE I USA Intelligence Cu & Sch, Ft Huachuca, ATTN: ATSI—CTD—DT

I Intelligence Material 0ev Ok, EWL . Ft Holabi rd 1 USA Intelligence Ctr & Sets , Ft Huachuca , ATTN: ATSI—CTD —CS

1 USA SE Signal Scts . Ft Gordon, ATTN: ATSO-EA I USA Intelligence Ctr & Sets , Ft Huachuce, ATIN: DAS/SAD

1 USA Chaplain Ctr & ScIs, Ft Hamilton , ATTN: ATSC-TE~

RD I USA Intelligence Cu & Sch, Ft Huach uca , ATTN : ATS I—TEM

1 USATSCH, Ft Eusti s . ATTN: Educ Advisor I USA Intelligen ce Ctr & Sch, Ft Huachuca . ATIN: Library

I USA War College, Carlisle Barracks , ATTN: Lib I COR , HO Ft Huachuca . ATTN: Tech Ref Div

2 WRAIR , Neuropsychiatry Div 2 CDR , USA Electronic Pryg Grd, ATTN: STEEP—MT—S

1 DLI , SDA. Monterey I COR , Project MASS1’ER, ATTN: Tech Info Center

1 USA Concept Anal Agcy , Bethesda, ATIN: MOCA-WGC 1 Hg MASSTER , USATRADOC , LNO

1 USA Concept Anal Agcy, Bethesda, ATTN: MOCA-MR 1 Research Institute . HO MASSTER . Ft H ood

1 USA Concept Anal Agcy, Bethesda, ATTN: MOCA-JF 1 USA Recruiting Cmd, FtSherdian , ATTN F USA RCPM—P

1 USA Artic Test Ctr, APO Seattle. ATTN: STEAC.MO.ASL 1 Senis.r Army Adv .. USAFAGOD/TAC, Elgin AF Aux FId No. 9

1 USA Artic Test CIr, APO Seattle, ATTN: AMSTE.PL.TS 1 HO USARPAC, DCSPER , APO SF 96658. AT’I’N: GPPE -SE

I USA Armament Cmd. Redstone Arsenal, ATTN: ATSK-TEM 1 Stimsori Lib, Academy of Health Sciences, Ft Sam Houston

1 USA Armament Cmd, Rock Island , ATTN: AMSAR-TOC I Marine Corps Inst ., ATrN~ Dean—MCI

1 FAA-NAFEC , Atlantic City, ATTN: Library 1 HQUSMC, Commandant , ATTN: Code MTMT 51

1 FAA-NAFEC , Atlantic City, ATTN Hum Engr Br 1 HOUSMC. Commandant . ATTN: Code MPh —20

1 FAA Aeronautical Ctr , Oklahoma CIty. ATIN: AAC.440 2 USCG Academy, New Lon don, A11’N: Admission

2 USA FId Arty Sch, Ft Sill, ATTN: Library 2 USCG Academy, New London, ATTN: Library

I USA Armor Sets , Ft Knox , ATTN: Weary I USC(

~ TrainIn g Ctr, NY , ATIN: CO

I USA Armor Sch, Ft Knox , ATTN : ATSB.DI-E I USCG Training Ctr. NV , ATTN: Educ Sec Ofc

1 USA Armor Sets, Ft Knox , ATTN: ATSB.DT.TP I USCG. PeyChOl Peg Br. DC, A’fl’N: OP 1/82

1 USA Armor ScIs , Ft Knox , ATTN: ATSB.CD.AO 1 HO Mid—Range Br , MC Det , Ouantlco, Afl ’N: P&S Div

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1 US Marine Corps Liaision Ofc , AMC, Alexandria , ATI’N: AMCG$—F 1 0.1 & Civil Inst of Enviro Medicine. Canada

1 USATRADOC , Ft Monroe, ATTN: ATRO—ED 1 AIR CRESS. Kensin gton , AT1’N: Info Sys Br

6 USATRADOC , Ft Monroe, ATTN: ATPR -AD I MIIItISI’pSykOICqlik Tjeneete. Ccp.hagen

1 USATRADOC , Ft Monroe, ATTN: ATTS—EA 1 MilItary Attache. French Embassy , ATTN: Doc Sec

1 USA Forces Cmd, Ft McPherson ~ ATTN: Library 1 Ifedecin Chef. C.E.R.P.A.—Ar,enal. Toulon/Naval Franca

2 USA Aviation Test Bd , Ft Roc ker , ATTN : STEBG—PO 1 PrIn Scientific Off , AppI Hum Iisgr Rid s Dlv , Mirsiatry

I USA Agcy for Aviation Safety, Ft Roc ker , ATTN: Library of Detense , New Dells,

I USA Agcy for Aviation Safety. Ft Rocker , ATTN: Educ Advisor 1 Per5 Rich OfCiibrary. AKA . I srael Defense Forces

1 USA Asi oh ion Sets , Ft Pucker , ATTN: P0 Drawer 0 1 Ministeris san Defens ie, 000P/KL Afd Sociaal

1 HOUSA Aviation Sys Cmd . St Louis , ATrN: AMSAV—ZDR Paydsologliche Zakun, The Hague. Netherlands

2 USA Aviation Sys last Act., Edwards AFB , AnN: SAVTE—T

1 USA Air Del Sets . Ft Bliss , ATTN: ATSA TEM

1 USA Air Mobility Rsch & 0ev Lab , Moff.tt FId, A’fl ’N: SAVDL—AS

1 USA Aviation Sets , Ret Tng Mgt , Ft Rucker , ATTN: ATST—T—RTM

1 USA Aviation Sets , CO. Ft Pucker , ATTN: ATST—D—A

1 HO, DARCOM , Alexandria , ATTN: AMXC D—TL

I 140, DARCOM , Alexandria. ATTN: CDR

1 US Milita ry Academy, West Point , ATTN: Serials Unit

1 US Military Academy, West Point , ATTN: Ofc of Milt Ldrshp

1 US Military Academy , West Point , ATTN: MAOR

1 USA Standardization Op. UK , FPO NV , ATTN: MASE—GC

1 Ofc of Nasal Rsch , Arlington , ATTN: Code 452

3 Ole of Nasal Rsch , Ar lington , ATTN: Code 458

1 Ofc of Naval Rsch , Arli ngto n, ATTN: Code 450

1 Ole of Naval Asc h , Arlington . ATTN: Code 441

1 Naval Aarospc Med Res La b, Pensacola , ATTN: Accus Sets Dlv

Naval Aerospc Med Res Lab , Pensacola . ATTN: Code Ui

I Nasal Aerospc Med Pen Lab . Penvacole . ATTN: Code L5

1 Chief of Nas Pers , ATTN: Pers’OR

1 NAVAIR STA , Norfolk . ATTN: Safety Ctr

1 NCv Oceanograph ic , DC, ATTN : Code 6251, Charts & TacIt

1 Cer ler of Nasal Anal , A1’l’N: Doe Ctr

1 Nav AirSysCom . ATTN: AIR—5313C

1 Nov BuMed , ATTN: 71J

1 NeeHelicopt .rSubSgua 2, FPO SF 96601

1 AFH RL (Fl) William AFB

1 AFHRL ITT) Lowr y AFB

1 AFHRL (AS) WPAFB , OH

2 AFHRL IDOJZ) Broo ks AFB

1 AEHAL IOOJN) Lack land AFB

1 HOUSAF (INYSO)

1 HOUSAF (DPXXAI

1 A FVT G bAD) Randolph AFB

3 AMAL (HE) WPAFB , OH

2 AF Inst of Tech , WPAFB . OH, ATTN: ENE/SL

I ATC (XPTDI Randolph AFB

1 USAF AeroMed Lib , Brooks AFB )SUL—4), ATTN: DOC SEC

1 AFOSR )NLI, Arli ngton

1 AF Log Cmd, McClellan AFB , A’fl ’N: ALC/DPCRB

1 Air Force Academy, CO, ATIN: Dept of Bet Scn

5 NaePers & Des Ctr , San Diego

2 Navy Mind Neuropsyc hiatric Rich Unit . San Diego

1 Nay Electronic Lab, San Diego . ATTN: Ass Lab

1 Nay TrngCen, Sass Diego , AT1’N: Code 9000’-Lib

1 NavPostGr aSch , Monterey. AZTN: Code 55A.

1 NavPostG raSch , Monterey, ATTN: Code 2124

1 NavTrngFqu ipCtr, Orlando . ATTN: Tech Lib

1 US Dept of Labor, DC, ATTN: Manpower Adnsin

1 US Dept of Justice, DC, ATTN: Drug Enforce Admin

1 Nat Bur of Standards, DC, ATTN: Computer Info Section

1 Nat Clearing House for MH—lnfo , Rockville

1 Denver Federal Ctr , Lakewood , ATIN: BLM

12 Defense Documentation Center

4 DIr Psych , Army Hq, Rueeell 01cc, Canberra

1 ScientifIc Advsr, MIt Sd, Army Hg, Russell Oft,, Canberra

I Mit and Air Attache, Austrian S-.sb.esy

I Centre do Recherche Des Facteurs, Humalne tie Ii Defense

Nationals , Brussals

2 Canadian J iint Staff Washington

1 C/AIr Staff , Royal Canadian AF. ATTN: Pars Std Anal Br

3 ChIef. CanadIan Oaf Rich Staff, An N: C/CRDS(W)

4 BrItish Oaf Staff , BrIti sh Embasey , W~ flinqton

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