U.S. patent number 3,898,747 [Application Number 05/482,544] was granted by the patent office on 1975-08-12 for laser system for weapon fire simulation.
This patent grant is currently assigned to The United States of America as represented by the Secretary of the Navy. Invention is credited to Albert H. Marshall.
United States Patent |
3,898,747 |
Marshall |
August 12, 1975 |
Laser system for weapon fire simulation
Abstract
A weapon direct fire kill simulator system in which a laser
transmitter ms of dual mode, narrow and broad beam projection,
capability, a hit receiver-actuator means and hit indication means
all fixed to a weapon to be simulated and having a trigger switch
are combined with a man target means having retroreflective apparel
or patches to reflect the narrow fire beam back to the hit
receiver-actuator and combined also with a 360.degree. kill
detector-actuator means to receive the kill beam to actuate a kill
indicator alarm also made a part of the man target wearing apparel.
The invention also contemplates a timing means and adjustable range
gate means to disable the system when the target is beyond the
simulated weapon's range, comparator means to eliminate noise
signals below the value of the hit indicator signals, and disabling
means to inactivate a man target once hit. In composite, the system
provides immediate hit indication to the trainee and kill
indication to the man target while also correcting for weapon
characteristics.
Inventors: |
Marshall; Albert H. (Maitland,
FL) |
Assignee: |
The United States of America as
represented by the Secretary of the Navy (Washington,
DC)
|
Family
ID: |
23916496 |
Appl.
No.: |
05/482,544 |
Filed: |
June 24, 1974 |
Current U.S.
Class: |
434/22; 42/106;
463/51; 42/116 |
Current CPC
Class: |
F41A
33/02 (20130101); F41G 3/2683 (20130101) |
Current International
Class: |
F41G
3/00 (20060101); F41G 3/26 (20060101); F41g
003/26 () |
Field of
Search: |
;35/25 ;273/101.1 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Michell; Robert W.
Assistant Examiner: Wolff; John H.
Attorney, Agent or Firm: Sciascia; Richard S. Pease; John
W.
Claims
What is claimed is:
1. A weapon fire kill simulator system comprising:
a. laser transmitter means for producing a narrow fire beam and a
wide angle kill beam,
b. laser power source means and hit detector-actuator means,
c. a weapon having a trigger switch and means for mounting all said
above mentioned means integral with said weapon and in position to
direct said laser means and said hit detector-actuator means in the
direction in which said weapon is aimed,
d. a man target carrying equipment including apparel or patches of
retroreflective material, a 360.degree. kill beam detector-actuator
means and an alarm system actuated from said kill detector-actuator
means upon energization of the latter,
e. said laser means being connected for producing said fire beam
when said trigger switch is closed to direct said fire beam to said
target and a retroreflected fire beam from said apparel to said hit
detector-actuator means,
f. said hit detector-actuator means being connected to actuate said
laser means to produce said wide angle kill beam to actuate said
kill detector-actuator and hence said alarm system.
2. Apparatus according to claim 1, including
a. hit indicator means fixed to said weapon and connected to
respond to actuation of said hit receiver-actuator to indicate a
hit to a trainee firing said weapon.
3. Apparatus according to claim 2, in which
a. said hit indicator means includes a light emitting diode counter
and a light emitting diode visible lamp, both fixed to said
weapon.
4. Apparatus according to claim 1, including
a. AND gate means,
b. range gate means comprising a timing pulse source connected to
provide an initiating actuating pulse to said laser transmitter
means responsive to actuation of said trigger pulse and an
additional pulse of selected time length commensurate with the
range of said weapon and provided as an enabling input to said AND
gate to exclude from said hit indicator means any hit signal whose
propagation time delay is greater than the time of laser pulse
return from maximum target range of the weapon being simulated.
5. Apparatus according to claim 1,
a. said hit receiver-actuator including a voltage comparator with
adjustable reference voltage input to selectively adjust the
sensitivity of said hit receiver-actuator to amplify only target
hit signals and exclude noise level signals up to the strength of a
target hit signal.
6. Apparatus according to claim 5,
a. said hit receiver-actuator including an avalanche type detector
and amplifying means connected to provide a hit signal input to
said voltage comparator.
7. Apparatus according to claim 6, including
a. AND gate means,
b. range gate means comprising a timing pulse source connected to
provide an initiating actuating pulse to said laser transmitter
means responsive to actuation of said trigger pulse and an
additional pulse of selected time length commensurate with the
range of said weapon and provided as an enabling input to said AND
gate to exclude from said hit indicator means any hit signal whose
propagation time delay is greater than the time of laser pulse
return from maximum target range of the weapon being simulated.
8. Apparatus according to claim 1,
a. said laser transmitter means being two laser transmitters
respectively for said hit and kill beams.
9. Apparatus according to claim 1,
a. said laser transmitter means being a single laser of dual mode
capability for producing said hit and kill beams.
Description
BACKGROUND OF THE INVENTION
The invention relates to the field of education and training in
direct fire weapons and to the field of simulation relating to a
man vs man combat system.
In order that military combat practices in the field of direct fire
weaponry may be carried out in a realistic, yet economical fashion,
such as to provide effective training comparable to the use of
operational equipment and live round ammunition, past efforts have
been directed to various forms of simulation equipment of
substantial weight, bulk and complexity. Thus, in the past
radiation transmitters have been employed for emitting a narrow
beam of optical radiation, the transmitter being mounted to be
aimed with the weapon simulated and combined with detector means
oriented to a target screen and hit or miss indicator means in the
form of audio or visual signal means. In man-to-man combat
simulation systems of this type the man must be covered with
numerous detectors which are easily destroyed or interfered with on
military maneuvers. Also a radio pack is required to transmit kill
data to the trainee firing his weapon. The use of a woven vest of
optic fibers to reduce the number of detectors has been tried with
lack of success because the vest becomes fragile and presents a
more stringent signal-to-noise problem. A basic system of laser
beam transmitter and man target apparel of retroreflective material
provides only an indication of kill to the trainee firing the
weapon but provides no kill data or indication to the man target
and no disablement of the man target.
SUMMARY OF THE INVENTION
The invention comprises an arrangement of a dual mode laser
transmitter and a receiver, together with hit indicator means in
integral relationship with a weapon to be simulated having switch
means for operating the transmitter in hit mode beam when the
trigger switch is actuated. The invention comprises in association
therewith a man target (simulating man to man engagement) wherein
the man target is provided with apparel or patches of
retroreflector material to reflect the fire beam to the
receiver-actuator and thereby actuate the transmitter to the second
or broad beam kill mode. The broad beam is received by kill
receiver-actuator (detector) means on the helmet of the man target
to actuate an alarm system which can only be shut off by turning a
key in a circuit which eliminates the man target from further
competition.
The invention also contemplates range gate means for inactivating
the laser transmitter when the target is beyond the weapon range,
and voltage comparator means for eliminating noise signals of a
level below the hit signal level.
DESCRIPTION OF THE DRAWING
FIG. 1 is a schematic functional presentation of a man-to-man wepon
fire kill simulator system incorporating the invention;
FIG. 2 is a schematic diagram of circuit details of the system of
FIG. 1;
FIG. 3 is a schematic diagram of a suitable amplifier and avalanche
detector employed in the system of FIGS. 1 and 2;
FIG. 4 shows a suitable circuit for the kill detector, alarm system
and key interlock employed to indicate a kill; and
FIG. 5 is a schematic of a suitable integrated circuit timer and
light emitting diode used in the circuit of FIG. 2.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to FIG. 1, there is shown two fighting men, trainees,
equipped with a weapon fire simulator system incorporating the
invention. The trainees 10 and 12 are identically equipped and for
convenience in reference, identical equipment will be given the
same numerical identification for each item of equipment. Thus,
trainees 10 and 12 are provided with helmets 14 having 360.degree.
kill receiver-actuators 16 for laser beams, alarm means 18, jackets
20 of retroreflective material and a laser type weapon simulator 22
having a trigger 24, a fire beam (narrow beam) laser 26, kill beam
(wide angle) laser 28, hit receiver-actuator 30, hit indicator 32,
power source means 34, and comparator and gating circuit means 36
to exclude noise signals and input signals beyond the intended
range of the weapon.
Also shown in FIG. 1 are the several rays which result from the
firing and hitting of a man target. Thus, actuation of the trigger
24 energizes the fire beam laser 26 which produces a narrow fire
beam 38 which upon striking the retroreflective jacket 20 of the
target man is retroreflected (beam 40) to actuate the hit
receiver-actuator 30. Receiver-actuator 30 then actuates the hit
indicator 32 to give an immediate hit indication to the trainee
firing the weapon but also activates the kill beam laser 28 which
produces a broad angle kill beam 42. The latter actuates the
360.degree. kill receiver-actuator 16 on the helmet 14 of the man
target which in turn activates an alarm means 18 on the man target
indicating to him that he is out of action.
Considering now details of circuitry suitable to implement the
functions described above, reference is made initially to FIG. 2.
The rifle trigger switch 24 when closed activates a laser pulser 25
and gallium arsenide laser diode 27 which together with collimating
lens 23 constitute the fire beam laser 26 of FIG. 1. Squeezing the
trigger switch 24 thus initiates the firing of the narrow fire beam
38 at the man target 12. If the narrow fire beam pulse 38 strikes
the retroreflective target 12, it is reflected back to the hit
receiver-actuator 30 which comprises an interference filter 44,
collecting lens 46, avalanche photo diode 50, transimpedance
amplifier 52 and an RC filter-comparator circuit, indicated
generally at 54. The retroreflected fire pulse 40 is filtered,
collected and focused on the avalanche photo diode 50 via the
filter 44 and the collecting lens 46, the photo diode 50 being a
high gain detector and the output thereof is amplified by the
transimpedance amplifier 52. To prevent noise signals from
affecting hit indication and count, the output of the amplifier 52
is threshold detected by a voltage comparator circuit 54.
Comparator circuit 54 includes an adjustable reference voltage
source provided from reference voltage V and potentiometers 56 and
58 connected to ground as indicated. An RC circuit including
capacitor 60 and resistor 62 is provided to couple the amplifier 52
to comparator 54.
When the output from the amplifier 52 exceeds the set reference
voltage, thus eliminating noise signals up to that set level, the
voltage comparator 54 generates a logical "one" signal pulse which
is passed via line 64 as one input to an AND gate 66 which forms
part of the gating circuit means 36. The other portion of the
gating circuit means 36 includes a current transformer 68 and one
shot range gate (multivibrator) 70. The current pulse from the
laser pulser 25 is sensed by the current transformer 68 which
triggers the one shot multivibrator range gate 70 which in turn
provides a logical one input as a second input to the AND gate 66
for a time duration equivalent to the weapon's maximum range. That
is, the range gate multivibrator holds the AND gate in potential
conducting condition for a time period up to that time which would
match the ballistic flight time at maximum range.
In end result then, if the "ones" from reflected target pulse and
range gate current transformer pulse are present simultaneously at
the two inputs to AND gate 66, the AND gate 66 generates a one at
its output.
This AND gate signal triggers three actions. First, the rifle as
indicated in FIG. 1 and in FIG. 2 is provided with a lamp, actually
a light emitting diode (LED) 32, and the output signal from gate 66
activates a timer 72 which activates the LED hit indicator 32 on
the rifle sight. Secondly, the rifle is, in a preferred embodiment,
provided with a hit counter 76 which can be built into the rifle
stock and which provides a record of target hits. Thirdly, the
output signal from the AND gate 66 triggers the kill beam (broad
beam) laser 28. Laser 28 comprises a laser pulser 78, gallium
arsenide diode 80 and collimating lens 82, and produces the
diverging broad angle kill beam 42 which in turn actuates the
360.degree. kill receiver-actuator 16 (FIG. 1) on the helment 14 of
the man target 12 and turns on the hit alarm 18 indicating to the
man target and to referees that the man is out of action.
The kill receiver-actuator 16 may comprise four photodiode
detectors located on four sides of a rectangular box type holder in
turn mounted on the helmet 14 as shown in FIG. 1. The number of
detectors on the helmet can be reduced from four if a prism or
optical fiber means are utilized.
One suitable receiver and alarm circuit for the helmet receiver
equipment is shown in FIG. 4. The circuit comprises a photo diode
84 coupled to a comparator circuit 86 via an operational amplifier
88 operating in the current to voltage amplifier mode and a voltage
gain amplifier 90. The remainder of the circuit comprises an alarm,
which could be a horn 92 operated through a silicon-controlled
rectifier (SCR) 94 which is actuated to "on" condition responsive
to the output signal of the voltage comparator 86 and to "off"
condition by operating a key switch indicated at 96.
When the kill beam laser pulse 42 (FIG. 4) is received by the diode
84 the amplifier 88 is actuated via the capacitor coupling 98. The
output of the amplifier 88 acting as a current to voltage converter
is inverted and further amplifier in the series connected second
operational amplifier 90. Capacitor coupling 91 is provided to ac
(alternating current) couple the two amplifiers. Capacitor 89
connected to ground indicated provides a noise filter and the ratio
of resistance values of feedback resistor 95 and series resistor 93
determines the voltage gain. The high speed voltage comparator 86,
responsive to an input from amplifier 90 on input line 100,
produces a high output voltage when the input voltage exceeds the
reference voltage (indicated). The reference voltage is set just
above noise level by a potentiometer 102 in the reference level
circuit. The high voltage output when produced by the comparator 86
is passed via diode 104 and lines 106, 108, 110 and 112 to the base
93 of SCR 94 to trigger the latter to on condition. The voltage
drop across resistor 114 actuates the hit alarm 92 which could be
an audio or visual alarm. A key is required to operate the switch
96 to shut the alarm off. It is contemplated that this key will be
a key removable from the rifle circuit as indicated at 116 in FIG.
2 such that the rifle held by the man hit is thereafter
inoperative. When switch 96 is opened the SCR 94 is turned off and
the alarm 92 is inactivated.
In FIG. 3 is shown a schematic of a suitable amplifier 52 and diode
detector 50 of FIG. 2. The avalanche photo diode is a
high-impedance device with avalanche gain. The avalanche detector
is a current source. The detector 50 output goes to a low-noise
high-speed transimpedance amplifier 52 designed for current
sources. The amplifier 52 provides an output voltage which is
linearly proportional to the detector's input current.
In reference to the timer 72 and LED 32 shown in FIG. 2, a suitable
timer is the Signetics 555 IC Timer, and a suitable circuit for
connecting the same to the LED is shown in detail in FIG. 5,
including suitable element values.
In the FIGS. 2 through 5, specific values of suitable elements are
provided.
It will be understood that various changes in the details, values
and arrangement of parts, which have been herein described and
illustrated in order to explain the nature of the invention, may be
made by those skilled in the art wihin the principle and scope of
the invention as expressed in the appended claims.
* * * * *